WO2020091571A1

WO2020091571A1 - Methods for transmitting and receiving uplinks in wireless communication system, and devices for same

Info

Publication number: WO2020091571A1
Application number: PCT/KR2019/014860
Authority: WO
Inventors: 신석민; 김선욱; 박창환; 안준기; 양석철; 황승계
Original assignee: 엘지전자 주식회사
Priority date: 2018-11-02
Filing date: 2019-11-04
Publication date: 2020-05-07

Abstract

The present specification provides a terminal which transmits uplinks to a base station in a wireless communication system. In particular, the terminal which transmits uplinks to a base station in a wireless communication system comprises a communication unit for transmitting and receiving radio signals, a processor, and at least one computer memory which can operably connect to the processor and, when executed by said at least one processor, stores instructions for carrying out operations. The operations comprise the steps of: receiving information related to an uplink resource from the base station; and transmitting an uplink to the base station via the uplink resource, wherein the uplink resource comprises a plurality of interlaced units, and a demodulation reference signal (DMRS) sequence having the same length as the total length of the plurality of interlaced units may be transmitted in the step of transmitting an uplink.

Description

Method for transmitting and receiving uplink in wireless communication system and apparatus therefor

The present specification relates to a method and apparatus for transmitting and receiving an uplink in a wireless communication system.

Mobile communication systems have been developed to provide voice services while ensuring user mobility. However, the mobile communication system has expanded not only to voice but also to data services, and now, due to the explosive increase in traffic, a shortage of resources is caused and users demand for a higher-speed service, so a more advanced mobile communication system is required. have.

The requirements of the next-generation mobile communication system are to support the explosive data traffic, the dramatic increase in the transmission rate per user, the largely increased number of connected devices, the very low end-to-end latency, and high energy efficiency. It should be possible. To this end, dual connectivity, Massive Multiple Input Multiple Output (MIMO), In-band Full Duplex, Non-Orthogonal Multiple Access (NOMA), and Super Wideband Various technologies such as wideband support and device networking have been studied.

An object of the present specification is to provide a method for a base station and a terminal to efficiently transmit and receive an uplink to a base station in a wireless communication system.

The technical problems to be achieved in this specification are not limited to the technical problems mentioned above, and other technical problems that are not mentioned will be clearly understood by those skilled in the art from the description below. Will be able to.

A terminal for transmitting an uplink to a base station in a wireless communication system according to an embodiment of the present disclosure, the terminal comprising: a communication unit for transmitting and receiving a radio signal; Processor; And at least one computer memory operatively connectable to the processor and storing instructions to perform operations when executed by the at least one processor, the operations uplink from the base station. Receiving information related to the resource; And transmitting an uplink to the base station through the uplink resource, wherein the uplink resource includes a plurality of interlace units, and the transmitting the uplink comprises: the plurality of interlaces. It may be characterized by transmitting a demodulation reference signal (DMRS) sequence having the same length as the entire length of.

Further, according to the present specification, the demodulation reference signal sequence is a form in which a plurality of demodulation reference signals are concatenated, and the number of the plurality of demodulation reference signals is the number of a plurality of unit resource element groups included in the plurality of interlaces. It can be characterized as.

Further, according to the present specification, the uplink resource includes a plurality of sub-bands to which the plurality of interlace units are mapped, and the plurality of reference signals are connected between the plurality of sub-bands. It can be characterized as.

Further, according to the present specification, the demodulation reference signal sequence may be characterized in that it comprises a guard band (guard band) between the plurality of sub-bands.

The method proposed in this specification has an effect that multiple terminals can efficiently transmit uplink data while minimizing the overhead of the base station.

The effects obtained in the present specification are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those skilled in the art from the following description. .

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included as part of the detailed description to aid understanding of the present specification, provide embodiments of the present specification, and describe the technical features of the present specification together with the detailed description.

1 is a diagram showing an example of a 5G scenario to which the present invention can be applied.

2 shows an AI device 100 according to an embodiment of the present invention.

3 shows an AI server 200 according to an embodiment of the present invention.

4 shows an AI system 1 according to an embodiment of the present invention.

5 illustrates a communication system 1 applied to the present invention.

6 illustrates a wireless communication device according to some embodiments of the present specification.

7 is another example of a block diagram of a wireless communication device according to some embodiments of the present disclosure.

8 shows a structure of a radio frame in a wireless communication system to which the present specification can be applied.

9 is a diagram illustrating a resource grid for one downlink slot in a wireless communication system to which the present specification can be applied.

10 shows a structure of a downlink subframe in a wireless communication system to which the present specification can be applied.

11 shows a structure of an uplink subframe in a wireless communication system to which the present specification can be applied.

12 shows an example of the overall system structure of the NR to which the method proposed in this specification can be applied.

13 shows a relationship between an uplink frame and a downlink frame in a wireless communication system to which the method proposed in this specification can be applied.

14 shows an example of a frame structure in an NR system.

15 shows an example of a resource grid supported by a wireless communication system to which the method proposed in this specification can be applied.

16 shows examples of an antenna port and a resource grid for each neurology to which the method proposed in this specification can be applied.

17 shows an example of narrowband operation and frequency diversity.

18 is a diagram showing physical channels that can be used for MTC and a general signal transmission method using them.

19 shows an example of an operation and configuration related to system information of an MTC system.

20 is a diagram showing an example of scheduling for each of the MTC and legacy LTE.

21 shows an example of a frame structure when the subcarrier interval is 15 kHz.

22 shows an example of a frame structure when the subcarrier spacing is 3.75 kHz.

23 shows an example of a resource grid for NB-IoT uplink.

24 is a diagram illustrating an example of physical channels that can be used for NB-IoT and a general signal transmission method using them.

25 is an example of an initial access procedure of NB-IoT.

26 is an example of an NB-IoT random access procedure.

27 shows the structure of a group of random access symbols.

28 shows an example of a wireless communication system supporting unlicensed bands applicable to the present invention.

29 is a flowchart of a CAP operation for transmitting a downlink signal through an unlicensed band of a base station.

30 is a flowchart of a Type 1 CAP operation of a terminal for uplink signal transmission.

31 illustrates one REG structure.

32 illustrates a non-interleaved CCE-REG mapping type.

33 illustrates an interleaved CCE-REG mapping type.

Figure 34 illustrates a block interleaver.

35 is a diagram illustrating an operation flowchart of a terminal and a base station performing idle mode PUR transmission of one or more physical channels / signals to which the method proposed in this specification can be applied.

36 shows an example of signaling between a base station and a terminal performing idle mode PUR transmission and reception of one or more physical channels / signals to which the method proposed in this specification can be applied.

37 shows an example of an operation flowchart of a terminal performing NR U-band transmission of one or more physical channels / signals to which the method proposed in this specification can be applied.

38 shows an example of an operation flowchart of a base station performing NR U-band transmission of one or more physical channels / signals to which the method proposed in this specification can be applied.

39 shows an example of signaling between a base station and a terminal performing NR U-band transmission and reception of one or more physical channels / signals to which the method proposed in this specification can be applied.

FIG. 40 is an example of an existing operation in which NPUSCH and DMRS sequences transmitted to 12 subcarriers occupy time / frequency resources, an example in which a terminal uses N / 2 length DMRS in transmitting uplink data, and different Half DMRS. It shows the frequency hopping pattern between.

FIG. 41 shows an example in which N = 6, the base station performs frequency division multiplexing (FDM) on frequency resources for two UEs and schedules the scheduling.

FIG. 42 shows an example in which two UEs are multiplexed in FIG. 41.

43 shows a case where a plurality of UEs using different number of subcarriers share time / frequency resources.

44 shows an example of a case where two UEs share all or part of UL time / frequency resources.

FIG. 45 shows a form in which UE1 repeatedly transmits a 6-length DMRS twice while changing a cyclic shift value.

46 shows a form in which UE1 continuously transmits two 6-length DMRSs according to specific rules.

FIG. 47 shows an example in which the base station sets different DMRS lengths in different frames to UE 1 and UE 2.

48 (A) shows an example of a DMRS sequence length for PUCCH according to method 5 of the second embodiment.

48 (B) shows an example of a DMRS sequence length for PUCCH according to method 6 of the second embodiment.

49 (A) illustrates a method of allocating resources according to method 7-1 of the second embodiment.

49 (B) illustrates a method of allocating resources according to method 7-2 of the second embodiment.

49 (C) illustrates a method of allocating resources according to method 7-3 of the second embodiment.

50 illustrates a method of allocating resources according to method 7-4 of the second embodiment.

51 illustrates a method of allocating resources according to method 7-5 of the second embodiment.

52 (A) illustrates a method of allocating resources according to methods 8-1 to 8-5 of the second embodiment.

FIG. 52 (B) shows an example of using PRBs present in the guard band in the method 7-5 having the interlace index of FIG. 42 (A).

53 (a) illustrates a method of allocating resources according to method 9-1.

53 (b) illustrates a method of allocating resources according to method 9-2.

53 (c) illustrates a method of allocating resources according to method 9-3.

54 (a) illustrates a method of allocating resources according to methods 9-4.

54 (b) illustrates a method of allocating resources according to methods 9-5.

54 (C) illustrates a method of allocating resources so that PRBs in interlaces spanning multiple SBs are not spaced apart.

FIG. 55 is a diagram illustrating an example in which a base station configures a combination of K orthogonal DMRSs and scrambling sequences, and then attempts to allocate N UEs to a specific time / frequency resource.

56 shows an example in which the base station configures a combination of K orthogonal DMRSs and scrambling sequences, and then allocates M UEs to a specific T / F resource.

57 shows an example in which a base station allocates a UE in consideration of the priority of UL data.

58 shows an example of an operation flowchart of a terminal transmitting and receiving signals and / or channels in a wireless communication system coexisting with another wireless communication system to which the method proposed in the present specification can be applied.

59 shows an example of an operation flowchart of a base station that transmits and receives signals and / or channels in a wireless communication system coexisting with another wireless communication system to which the method proposed in the present specification can be applied.

60 shows a data exchange sequence between a base station / terminal that transmits and receives signals and / or channels in a wireless communication system coexisting with other wireless communication systems, to which the method proposed in the present specification can be applied.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION The detailed description set forth below, in conjunction with the accompanying drawings, is intended to describe exemplary embodiments of the invention, and is not intended to represent the only embodiments in which the invention may be practiced. The following detailed description includes specific details to provide a thorough understanding of the present invention. However, one skilled in the art knows that the present invention can be practiced without these specific details.

In some cases, in order to avoid obscuring the concept of the present invention, well-known structures and devices may be omitted, or block diagrams centered on the core functions of each structure and device may be illustrated.

In this specification, a base station has a meaning as a terminal node of a network that directly communicates with a terminal. Certain operations described in this document as being performed by a base station may be performed by an upper node of the base station in some cases. That is, it is apparent that various operations performed for communication with a terminal in a network composed of a plurality of network nodes including a base station can be performed by a base station or other network nodes other than the base station. The term 'base station (BS)' may be replaced by terms such as a fixed station, Node B, evolved-NodeB (eNB), base transceiver system (BTS), or access point (AP). . In addition, the 'terminal (Terminal)' may be fixed or mobile, UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), SS (Subscriber Station), AMS ( It can be replaced with terms such as Advanced Mobile Station (WT), Wireless terminal (WT), Machine-Type Communication (MTC) device, Machine-to-Machine (M2M) device, and Device-to-Device (D2D) device.

Hereinafter, downlink (DL) means communication from a base station to a terminal, and uplink (UL) means communication from a terminal to a base station. In the downlink, the transmitter may be part of the base station, and the receiver may be part of the terminal. In the uplink, the transmitter may be part of the terminal, and the receiver may be part of the base station.

Certain terms used in the following description are provided to help understanding of the present invention, and the use of these specific terms may be changed to other forms without departing from the technical spirit of the present invention.

The following technologies are code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and NOMA. (non-orthogonal multiple access), and the like. CDMA may be implemented by radio technology such as universal terrestrial radio access (UTRA) or CDMA2000. TDMA may be implemented with radio technologies such as global system for mobile communications (GSM) / general packet radio service (GPRS) / enhanced data rates for GSM evolution (EDGE). OFDMA may be implemented with wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and evolved UTRA (E-UTRA). UTRA is part of a universal mobile telecommunications system (UMTS). The 3rd generation partnership project (3GPP) long term evolution (LTE) is part of evolved UMTS (E-UMTS) using E-UTRA, and adopts OFDMA in the downlink and SC-FDMA in the uplink. LTE-A (advanced) is an evolution of 3GPP LTE.

Embodiments of the invention may be supported by standard documents disclosed in at least one of the wireless access systems IEEE 802, 3GPP and 3GPP2. That is, steps or parts that are not described in order to clearly reveal the technical idea of the present invention among the embodiments of the present invention may be supported by the documents. Also, all terms disclosed in this document may be described by the standard document.

For clarity, 3GPP LTE / LTE-A is mainly described, but the technical features of the present invention are not limited thereto.

<5G scenario>

The three main requirements areas of 5G are: (1) Enhanced Mobile Broadband (eMBB) area, (2) Massive Machine Type Communication (mMTC) area, and (3) Super-reliability and Ultra-reliable and Low Latency Communications (URLLC) domain.

Some use cases may require multiple areas for optimization, and other use cases may focus on only one key performance indicator (KPI). 5G is a flexible and reliable way to support these various use cases.

eMBB goes far beyond basic mobile Internet access, and covers media and entertainment applications in rich interactive work, cloud or augmented reality. Data is one of the key drivers of 5G, and it may not be possible to see dedicated voice services for the first time in the 5G era. In 5G, it is expected that voice will be processed as an application program simply using the data connection provided by the communication system. The main causes for increased traffic volume are increased content size and increased number of applications requiring high data rates. Streaming services (audio and video), interactive video and mobile internet connections will become more widely used as more devices connect to the internet. Many of these applications require always-on connectivity to push real-time information and notifications to users. Cloud storage and applications are rapidly increasing in mobile communication platforms, which can be applied to both work and entertainment. And, cloud storage is a special use case that drives the growth of uplink data transfer rate. 5G is also used for remote work in the cloud, requiring much lower end-to-end delay to maintain a good user experience when a tactile interface is used. Entertainment For example, cloud gaming and video streaming are another key factor in increasing demand for mobile broadband capabilities. Entertainment is essential for smartphones and tablets anywhere, including high mobility environments such as trains, cars and airplanes. Another use case is augmented reality and information retrieval for entertainment. Here, augmented reality requires very low delay and instantaneous amount of data.

In addition, one of the most anticipated 5G use cases is the ability to seamlessly connect embedded sensors in all fields, namely mMTC. It is predicted that by 2020, there will be 20.4 billion potential IoT devices. Industrial IoT is one of the areas where 5G plays a key role in enabling smart cities, asset tracking, smart utilities, agriculture and security infrastructure.

URLLC includes new services that will transform the industry through ultra-reliable / low-latency links, such as remote control of the main infrastructure and self-driving vehicles. Reliability and level of delay are essential for smart grid control, industrial automation, robotics, drone control and coordination.

Next, a number of use cases will be described in more detail.

5G can complement fiber-to-the-home (FTTH) and cable-based broadband (or DOCSIS) as a means to provide streams rated at hundreds of megabits per second to gigabit per second. This fast speed is required to deliver TV in 4K (6K, 8K and higher) resolutions as well as virtual and augmented reality. Virtual Reality (VR) and Augmented Reality (AR) applications include almost immersive sports events. Certain application programs may require special network settings. For VR games, for example, game companies may need to integrate the core server with the network operator's edge network server to minimize latency.

Automotive is expected to be an important new driver for 5G, along with many use cases for mobile communications to vehicles. For example, entertainment for passengers requires simultaneous high capacity and high mobility mobile broadband. This is because future users continue to expect high-quality connections regardless of their location and speed. Another example of application in the automotive field is the augmented reality dashboard. It identifies objects in the dark over what the driver sees through the front window, and superimposes and displays information telling the driver about the distance and movement of the object. In the future, wireless modules will enable communication between vehicles, exchange of information between the vehicle and the supporting infrastructure and exchange of information between the vehicle and other connected devices (eg, devices carried by pedestrians). The safety system helps the driver to reduce the risk of accidents by guiding alternative courses of action to make driving safer. The next step will be remote control or a self-driven vehicle. This requires very reliable and very fast communication between different self-driving vehicles and between the vehicle and the infrastructure. In the future, self-driving vehicles will perform all driving activities, and drivers will focus only on traffic beyond which the vehicle itself cannot identify. The technical requirements of self-driving vehicles require ultra-low delays and ultra-high-speed reliability to increase traffic safety to levels beyond human reach.

Smart cities and smart homes, referred to as smart societies, will be embedded in high-density wireless sensor networks. The distributed network of intelligent sensors will identify the conditions for cost and energy-efficient maintenance of the city or home. Similar settings can be made for each assumption. Temperature sensors, window and heating controllers, burglar alarms and consumer electronics are all connected wirelessly. Many of these sensors are typically low data rates, low power and low cost. However, for example, real-time HD video may be required in certain types of devices for surveillance.

The consumption and distribution of energy, including heat or gas, is highly decentralized, requiring automated control of a distributed sensor network. The smart grid interconnects these sensors using digital information and communication technologies to collect information and act accordingly. This information can include supplier and consumer behavior, so smart grids can improve efficiency, reliability, economics, production sustainability and distribution of fuels like electricity in an automated way. The smart grid can be viewed as another sensor network with low latency.

The health sector has many applications that can benefit from mobile communications. The communication system can support telemedicine that provides clinical care from a distance. This can help reduce barriers to distance and improve access to medical services that are not continuously available in remote rural areas. It is also used to save lives in critical care and emergency situations. A wireless sensor network based on mobile communication can provide remote monitoring and sensors for parameters such as heart rate and blood pressure.

Wireless and mobile communications are becoming increasingly important in industrial applications. Wiring is expensive to install and maintain. Thus, the possibility of replacing cables with wireless links that can be reconfigured is an attractive opportunity in many industries. However, achieving this requires that the wireless connection operates with cable-like delay, reliability and capacity, and that management is simplified. Low latency and very low error probability are new requirements that need to be connected to 5G.

Logistics and freight tracking are important use cases for mobile communications that enable the tracking of inventory and packages from anywhere using location-based information systems. Logistics and freight tracking use cases typically require low data rates, but require wide range and reliable location information.

Artificial intelligence refers to the field of studying artificial intelligence or a methodology to create it, and machine learning (machine learning) refers to the field of studying the methodology to define and solve various problems in the field of artificial intelligence. do. Machine learning is defined as an algorithm that improves the performance of a job through steady experience.

An artificial neural network (ANN) is a model used in machine learning, and may mean an overall model having a problem-solving ability, composed of artificial neurons (nodes) forming a network through a combination of synapses. The artificial neural network may be defined by a connection pattern between neurons of different layers, a learning process for updating model parameters, and an activation function that generates output values.

The artificial neural network may include an input layer, an output layer, and optionally one or more hidden layers. Each layer contains one or more neurons, and the artificial neural network can include neurons and synapses connecting neurons. In an artificial neural network, each neuron may output a function value of an input function input through a synapse, a weight, and an active function for bias.

The model parameter means a parameter determined through learning, and includes weights of synaptic connections and bias of neurons. In addition, the hyperparameter means a parameter that must be set before learning in a machine learning algorithm, and includes learning rate, number of iterations, mini-batch size, initialization function, and the like.

The purpose of training an artificial neural network can be seen as determining model parameters that minimize the loss function. The loss function can be used as an index for determining an optimal model parameter in the learning process of an artificial neural network.

Machine learning can be classified into supervised learning, unsupervised learning, and reinforcement learning according to the learning method.

Supervised learning refers to a method of training an artificial neural network while a label for training data is given, and a label is a correct answer (or a result value) that the artificial neural network must infer when the training data is input to the artificial neural network. Can mean Unsupervised learning may refer to a method of training an artificial neural network without a label for learning data. Reinforcement learning may mean a learning method in which an agent defined in a certain environment is trained to select an action or a sequence of actions to maximize cumulative reward in each state.

Machine learning implemented as a deep neural network (DNN) that includes a plurality of hidden layers among artificial neural networks is also referred to as deep learning (deep learning), and deep learning is part of machine learning. In the following, machine learning is used to mean deep learning.

<Robot>

A robot can mean a machine that automatically handles or acts on a task given by its own capabilities. In particular, a robot having a function of recognizing the environment and performing an operation by determining itself can be referred to as an intelligent robot.

Robots can be classified into industrial, medical, household, and military according to the purpose or field of use.

The robot may be provided with a driving unit including an actuator or a motor to perform various physical operations such as moving a robot joint. In addition, the movable robot includes a wheel, a brake, a propeller, and the like in the driving unit, so that it can travel on the ground or fly in the air through the driving unit.

<Self-Driving, Autonomous-Driving>

Autonomous driving refers to the technology of driving on its own, and autonomous driving means a vehicle that operates without a user's manipulation or with a minimum manipulation of the user.

For example, in autonomous driving, a technology that maintains a driving lane, a technology that automatically adjusts speed such as adaptive cruise control, a technology that automatically drives along a predetermined route, and a technology that automatically sets a route when a destination is set, etc. All of this can be included.

The vehicle includes a vehicle having only an internal combustion engine, a hybrid vehicle having both an internal combustion engine and an electric motor, and an electric vehicle having only an electric motor, and may include a train, a motorcycle, etc. as well as a vehicle.

At this time, the autonomous vehicle can be viewed as a robot having an autonomous driving function.

<XR: eXtended Reality>

Augmented reality refers to virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology provides real-world objects or backgrounds only as CG images, AR technology provides CG images made virtually on real objects, and MR technology is a computer that mixes and combines virtual objects in the real world. Graphics technology.

MR technology is similar to AR technology in that it shows both real and virtual objects. However, in AR technology, a virtual object is used as a complement to a real object, whereas in MR technology, there is a difference in that a virtual object and a real object are used with equal characteristics.

XR technology can be applied to Head-Mount Display (HMD), Head-Up Display (HUD), mobile phone, tablet PC, laptop, desktop, TV, digital signage, etc. It can be called.

2 shows an AI device 100 according to an embodiment of the present invention.

The AI device 100 is a TV, projector, mobile phone, smartphone, desktop computer, laptop, digital broadcasting terminal, PDA (personal digital assistants), PMP (portable multimedia player), navigation, tablet PC, wearable device, set-top box (STB) ), DMB receivers, radios, washing machines, refrigerators, desktop computers, digital signage, robots, vehicles, and the like.

Referring to FIG. 2, the terminal 100 includes a communication unit 110, an input unit 120, a running processor 130, a sensing unit 140, an output unit 150, a memory 170, a processor 180, etc. It can contain.

The communication unit 110 may transmit and receive data to and from external devices such as other AI devices 100a to 100e or the AI server 200 using wired / wireless communication technology. For example, the communication unit 110 may transmit and receive sensor information, a user input, a learning model, a control signal, etc. with external devices.

At this time, the communication technology used by the communication unit 110 includes Global System for Mobile Communication (GSM), Code Division Multi Access (CDMA), Long Term Evolution (LTE), 5G, Wireless LAN (WLAN), Wireless-Fidelity (Wi-Fi). ), Bluetooth ™, Radio Frequency Identification (RFID), Infrared Data Association (IrDA), ZigBee, Near Field Communication (NFC), and the like.

The input unit 120 may acquire various types of data.

At this time, the input unit 120 may include a camera for inputting a video signal, a microphone for receiving an audio signal, a user input unit for receiving information from a user, and the like. Here, the camera or microphone is treated as a sensor, and the signal obtained from the camera or microphone may be referred to as sensing data or sensor information.

The input unit 120 may acquire training data for model training and input data to be used when obtaining an output using the training model. The input unit 120 may obtain raw input data. In this case, the processor 180 or the learning processor 130 may extract input features as pre-processing of the input data.

The learning processor 130 may train a model composed of artificial neural networks using the training data. Here, the trained artificial neural network may be referred to as a learning model. The learning model can be used to infer a result value for new input data rather than learning data, and the inferred value can be used as a basis for determining to perform an action.

At this time, the learning processor 130 may perform AI processing together with the learning processor 240 of the AI server 200.

At this time, the learning processor 130 may include a memory integrated or implemented in the AI device 100. Alternatively, the learning processor 130 may be implemented using memory 170, external memory directly coupled to the AI device 100, or memory maintained in the external device.

The sensing unit 140 may acquire at least one of AI device 100 internal information, AI device 100 environment information, and user information using various sensors.

At this time, the sensors included in the sensing unit 140 include a proximity sensor, an illuminance sensor, an acceleration sensor, a magnetic sensor, a gyro sensor, an inertial sensor, an RGB sensor, an IR sensor, a fingerprint recognition sensor, an ultrasonic sensor, an optical sensor, a microphone, and a lidar. , And radar.

The output unit 150 may generate output related to vision, hearing, or tactile sense.

At this time, the output unit 150 may include a display unit for outputting visual information, a speaker for outputting auditory information, a haptic module for outputting tactile information, and the like.

The memory 170 may store data supporting various functions of the AI device 100. For example, the memory 170 may store input data, learning data, learning models, learning history, etc. acquired by the input unit 120.

The processor 180 may determine at least one executable action of the AI device 100 based on information determined or generated using a data analysis algorithm or a machine learning algorithm. Also, the processor 180 may control components of the AI device 100 to perform a determined operation.

To this end, the processor 180 may request, search, receive, or utilize data of the learning processor 130 or the memory 170, and perform an operation that is predicted or determined to be preferable among the at least one executable operation. It is possible to control the components of the AI device 100 to execute.

At this time, the processor 180 may generate a control signal for controlling the corresponding external device, and transmit the generated control signal to the corresponding external device when it is necessary to link the external device to perform the determined operation.

The processor 180 may acquire intention information for a user input, and determine a user's requirement based on the obtained intention information.

At this time, the processor 180 uses at least one of a Speech To Text (STT) engine for converting voice input into a string or a Natural Language Processing (NLP) engine for acquiring intention information of natural language, and a user Intention information corresponding to an input may be obtained.

At this time, at least one of the STT engine or the NLP engine may be configured as an artificial neural network at least partially learned according to a machine learning algorithm. And, at least one or more of the STT engine or the NLP engine is learned by the learning processor 130, learned by the learning processor 240 of the AI server 200, or learned by distributed processing thereof May be

The processor 180 collects history information including the user's feedback on the operation content or operation of the AI device 100 and stores it in the memory 170 or the running processor 130, or the AI server 200, etc. Can be sent to external devices. The collected history information can be used to update the learning model.

The processor 180 may control at least some of the components of the AI device 100 to drive an application program stored in the memory 170. Furthermore, the processor 180 may operate by combining two or more of the components included in the AI device 100 with each other to drive the application program.

3 shows an AI server 200 according to an embodiment of the present invention.

Referring to FIG. 3, the AI server 200 may refer to an apparatus for learning an artificial neural network using a machine learning algorithm or using a trained artificial neural network. Here, the AI server 200 may be composed of a plurality of servers to perform distributed processing, or may be defined as a 5G network. At this time, the AI server 200 is included as a configuration of a part of the AI device 100, and may perform at least a part of AI processing together.

The AI server 200 may include a communication unit 210, a memory 230, a running processor 240 and a processor 260.

The communication unit 210 may transmit and receive data with an external device such as the AI device 100.

The memory 230 may include a model storage unit 231. The model storage unit 231 may store a model (or artificial neural network, 231a) being trained or trained through the learning processor 240.

The learning processor 240 may train the artificial neural network 231a using learning data. The learning model may be used while being mounted on the AI server 200 of the artificial neural network, or may be mounted and used on an external device such as the AI device 100.

The learning model can be implemented in hardware, software, or a combination of hardware and software. When part or all of the learning model is implemented in software, one or more instructions constituting the learning model may be stored in the memory 230.

The processor 260 may infer the result value for the new input data using the learning model, and generate a response or control command based on the inferred result value.

4 shows an AI system 1 according to an embodiment of the present invention.

Referring to FIG. 4, the AI system 1 includes at least one of an AI server 200, a robot 100a, an autonomous vehicle 100b, an XR device 100c, a smartphone 100d, or a home appliance 100e. It is connected to the cloud network 10. Here, the robot 100a to which AI technology is applied, the autonomous vehicle 100b, the XR device 100c, the smartphone 100d, or the home appliance 100e may be referred to as AI devices 100a to 100e.

The cloud network 10 may form a part of the cloud computing infrastructure or may mean a network existing in the cloud computing infrastructure. Here, the cloud network 10 may be configured using a 3G network, a 4G or a Long Term Evolution (LTE) network, or a 5G network.

That is, each device (100a to 100e, 200) constituting the AI system 1 may be connected to each other through the cloud network (10). In particular, the devices 100a to 100e and 200 may communicate with each other through a base station, but may communicate with each other directly without passing through the base station.

The AI server 200 may include a server performing AI processing and a server performing operations on big data.

The AI server 200 includes at least one or more among robots 100a, autonomous vehicles 100b, XR devices 100c, smart phones 100d, or home appliances 100e, which are AI devices constituting the AI system 1. It is connected through the cloud network 10 and can assist at least some of the AI processing of the connected AI devices 100a to 100e.

At this time, the AI server 200 may train the artificial neural network according to the machine learning algorithm in place of the AI devices 100a to 100e, and may directly store the learning model or transmit it to the AI devices 100a to 100e.

At this time, the AI server 200 receives input data from the AI devices 100a to 100e, infers a result value to the received input data using a learning model, and issues a response or control command based on the inferred result value. It can be generated and transmitted to AI devices 100a to 100e.

Alternatively, the AI devices 100a to 100e may infer a result value with respect to input data using a direct learning model and generate a response or control command based on the inferred result value.

Hereinafter, various embodiments of the AI devices 100a to 100e to which the above-described technology is applied will be described. Here, the AI devices 100a to 100e illustrated in FIG. 3 may be viewed as specific embodiments of the AI device 100 illustrated in FIG. 1.

AI technology is applied to the robot 100a, and may be implemented as a guide robot, a transport robot, a cleaning robot, a wearable robot, an entertainment robot, a pet robot, and an unmanned flying robot.

The robot 100a may include a robot control module for controlling an operation, and the robot control module may mean a software module or a chip implemented with hardware.

The robot 100a acquires state information of the robot 100a using sensor information obtained from various types of sensors, detects (recognizes) surrounding environment and objects, generates map data, or moves and travels. You can decide on a plan, determine a response to user interaction, or determine an action.

Here, the robot 100a may use sensor information acquired from at least one sensor among a lidar, a radar, and a camera in order to determine a movement route and a driving plan.

The robot 100a may perform the above operations using a learning model composed of at least one artificial neural network. For example, the robot 100a may recognize a surrounding environment and an object using a learning model, and may determine an operation using the recognized surrounding environment information or object information. Here, the learning model may be directly learned from the robot 100a or may be learned from an external device such as the AI server 200.

At this time, the robot 100a may perform an operation by generating a result using a direct learning model, but transmits sensor information to an external device such as the AI server 200 and receives the result generated accordingly. You may.

The robot 100a determines a moving path and a driving plan using at least one of map data, object information detected from sensor information, or object information obtained from an external device, and controls the driving unit to determine the determined moving path and driving plan. Accordingly, the robot 100a can be driven.

The map data may include object identification information for various objects arranged in a space in which the robot 100a moves. For example, the map data may include object identification information for fixed objects such as walls and doors and movable objects such as flower pots and desks. In addition, the object identification information may include a name, type, distance, and location.

In addition, the robot 100a may perform an operation or travel by controlling a driving unit based on a user's control / interaction. At this time, the robot 100a may acquire intention information of an interaction according to a user's motion or voice utterance, and determine an answer based on the obtained intention information to perform an operation.

The autonomous driving vehicle 100b is applied with AI technology and can be implemented as a mobile robot, a vehicle, or an unmanned aerial vehicle.

The autonomous driving vehicle 100b may include an autonomous driving control module for controlling an autonomous driving function, and the autonomous driving control module may refer to a software module or a chip implemented with hardware. The autonomous driving control module may be included therein as a configuration of the autonomous driving vehicle 100b, but may be configured and connected to a separate hardware outside the autonomous driving vehicle 100b.

The autonomous vehicle 100b acquires state information of the autonomous vehicle 100b using sensor information obtained from various types of sensors, detects (recognizes) surrounding objects and objects, generates map data, The route and driving plan may be determined, or an operation may be determined.

Here, the autonomous vehicle 100b may use sensor information obtained from at least one sensor among a lidar, a radar, and a camera, like the robot 100a, to determine a movement path and a driving plan.

In particular, the autonomous driving vehicle 100b may receive sensor information from external devices or recognize an environment or an object for an area where a field of view is obscured or a predetermined distance or more, or receive information recognized directly from external devices. .

The autonomous vehicle 100b may perform the above-described operations using a learning model composed of at least one artificial neural network. For example, the autonomous vehicle 100b may recognize a surrounding environment and an object using a learning model, and may determine a driving line using the recognized surrounding environment information or object information. Here, the learning model may be learned directly from the autonomous vehicle 100b or may be learned from an external device such as the AI server 200.

At this time, the autonomous vehicle 100b may perform an operation by generating a result using a direct learning model, but transmits sensor information to an external device such as the AI server 200 and receives the generated result accordingly. You can also do

The autonomous vehicle 100b determines a moving path and a driving plan using at least one of map data, object information detected from sensor information, or object information obtained from an external device, and controls the driving unit to determine the moving path and driving According to the plan, the autonomous vehicle 100b may be driven.

The map data may include object identification information for various objects arranged in a space (for example, a road) in which the autonomous vehicle 100b travels. For example, the map data may include object identification information for fixed objects such as street lights, rocks, buildings, and movable objects such as vehicles and pedestrians. In addition, the object identification information may include a name, type, distance, and location.

In addition, the autonomous vehicle 100b may perform an operation or travel by controlling a driving unit based on a user's control / interaction. At this time, the autonomous driving vehicle 100b may acquire intention information of an interaction according to a user's motion or voice utterance, and determine an answer based on the obtained intention information to perform an operation.

AI technology is applied to the XR device 100c, HMD (Head-Mount Display), HUD (Head-Up Display) provided in a vehicle, television, mobile phone, smart phone, computer, wearable device, home appliance, digital signage , It can be implemented as a vehicle, a fixed robot or a mobile robot.

The XR device 100c generates location data and attribute data for 3D points by analyzing 3D point cloud data or image data obtained through various sensors or from an external device, thereby providing information about surrounding space or real objects. The XR object to be acquired and output can be rendered and output. For example, the XR device 100c may output an XR object including additional information about the recognized object in correspondence with the recognized object.

The XR device 100c may perform the above operations using a learning model composed of at least one artificial neural network. For example, the XR device 100c may recognize a real object from 3D point cloud data or image data using a learning model, and provide information corresponding to the recognized real object. Here, the learning model may be directly trained in the XR device 100c or may be learned in an external device such as the AI server 200.

At this time, the XR device 100c may perform an operation by generating a result using a direct learning model, but transmits sensor information to an external device such as the AI server 200 and receives the generated result accordingly. You can also do

The robot 100a is applied with AI technology and autonomous driving technology, and can be implemented as a guide robot, a transport robot, a cleaning robot, a wearable robot, an entertainment robot, a pet robot, and an unmanned flying robot.

The robot 100a to which AI technology and autonomous driving technology are applied may mean a robot itself having an autonomous driving function or a robot 100a that interacts with the autonomous driving vehicle 100b.

The robot 100a having an autonomous driving function may collectively refer to moving devices by moving itself or determining the moving line according to a given moving line without user control.

The robot 100a and the autonomous vehicle 100b having an autonomous driving function may use a common sensing method to determine one or more of a moving path or a driving plan. For example, the robot 100a and the autonomous vehicle 100b having an autonomous driving function may determine one or more of a moving route or a driving plan using information sensed through a lidar, a radar, and a camera.

The robot 100a interacting with the autonomous vehicle 100b exists separately from the autonomous vehicle 100b, and is connected to an autonomous vehicle function inside or outside the autonomous vehicle 100b, or the autonomous vehicle 100b ) Can perform the operation associated with the user on board.

At this time, the robot 100a that interacts with the autonomous vehicle 100b acquires sensor information on behalf of the autonomous vehicle 100b and provides it to the autonomous vehicle 100b, acquires sensor information, and obtains environment information or By generating object information and providing it to the autonomous vehicle 100b, it is possible to control or assist the autonomous vehicle driving function of the autonomous vehicle 100b.

Alternatively, the robot 100a interacting with the autonomous vehicle 100b may monitor a user on the autonomous vehicle 100b or control a function of the autonomous vehicle 100b through interaction with the user. . For example, when it is determined that the driver is in a drowsy state, the robot 100a may activate the autonomous driving function of the autonomous vehicle 100b or assist control of a driving unit of the autonomous vehicle 100b. Here, the function of the autonomous driving vehicle 100b controlled by the robot 100a may include not only an autonomous driving function, but also a function provided by a navigation system or an audio system provided inside the autonomous driving vehicle 100b.

Alternatively, the robot 100a interacting with the autonomous vehicle 100b may provide information or assist a function to the autonomous vehicle 100b from outside the autonomous vehicle 100b. For example, the robot 100a may provide traffic information including signal information to the autonomous vehicle 100b, such as a smart traffic light, or interact with the autonomous vehicle 100b, such as an automatic electric charger for an electric vehicle. An electric charger can also be automatically connected to the charging port.

The robot 100a is applied with AI technology and XR technology, and can be implemented as a guide robot, a transport robot, a cleaning robot, a wearable robot, an entertainment robot, a pet robot, an unmanned flying robot, and a drone.

The robot 100a to which XR technology is applied may mean a robot that is a target of control / interaction within an XR image. In this case, the robot 100a is separated from the XR device 100c and can be interlocked with each other.

When the robot 100a, which is the object of control / interaction within the XR image, acquires sensor information from sensors including a camera, the robot 100a or the XR device 100c generates an XR image based on the sensor information. And, the XR device 100c may output the generated XR image. In addition, the robot 100a may operate based on a control signal input through the XR device 100c or a user's interaction.

For example, the user can check the XR image corresponding to the viewpoint of the robot 100a remotely linked through an external device such as the XR device 100c, and adjust the autonomous driving path of the robot 100a through interaction or , You can control the operation or driving, or check the information of the surrounding objects.

The autonomous vehicle 100b is applied with AI technology and XR technology, and may be implemented as a mobile robot, a vehicle, or an unmanned aerial vehicle.

The autonomous driving vehicle 100b to which the XR technology is applied may mean an autonomous driving vehicle having a means for providing an XR image or an autonomous driving vehicle targeted for control / interaction within the XR image. In particular, the autonomous vehicle 100b, which is the object of control / interaction within the XR image, is distinguished from the XR device 100c and may be interlocked with each other.

The autonomous vehicle 100b having a means for providing an XR image may acquire sensor information from sensors including a camera, and output an XR image generated based on the acquired sensor information. For example, the autonomous vehicle 100b may provide an XR object corresponding to a real object or an object on the screen to the occupant by outputting an XR image with a HUD.

At this time, when the XR object is output to the HUD, at least a portion of the XR object may be output so as to overlap with an actual object facing the occupant's gaze. On the other hand, when the XR object is output to a display provided inside the autonomous vehicle 100b, at least a part of the XR object may be output to overlap with an object in the screen. For example, the autonomous vehicle 100b may output XR objects corresponding to objects such as lanes, other vehicles, traffic lights, traffic signs, two-wheeled vehicles, pedestrians, buildings, and the like.

When the autonomous vehicle 100b, which is the object of control / interaction within the XR image, acquires sensor information from sensors including a camera, the autonomous vehicle 100b or the XR device 100c is based on the sensor information. The XR image is generated, and the XR device 100c may output the generated XR image. In addition, the autonomous vehicle 100b may operate based on a user's interaction or a control signal input through an external device such as the XR device 100c.

5 illustrates a communication system 1 applied to the present invention.

Referring to FIG. 5, the communication system 1 applied to the present invention includes a wireless device, a base station and a network. Here, the wireless device means a device that performs communication using a wireless access technology (eg, 5G NR (New RAT), Long Term Evolution (LTE)), and may be referred to as a communication / wireless / 5G device. Although not limited to this, the wireless device includes a robot 100a, a vehicle 100b-1, 100b-2, an XR (eXtended Reality) device 100c, a hand-held device 100d, and a home appliance 100e. ), Internet of Thing (IoT) devices 100f, and AI devices / servers 400. For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous driving vehicle, a vehicle capable of performing inter-vehicle communication, and the like. Here, the vehicle may include a UAV (Unmanned Aerial Vehicle) (eg, a drone). XR devices include Augmented Reality (AR) / Virtual Reality (VR) / Mixed Reality (MR) devices, Head-Mounted Device (HMD), Head-Up Display (HUD) provided in vehicles, televisions, smartphones, It may be implemented in the form of a computer, wearable device, home appliance, digital signage, vehicle, robot, or the like. The mobile device may include a smart phone, a smart pad, a wearable device (eg, a smart watch, smart glasses), a computer (eg, a notebook, etc.). Household appliances may include a TV, a refrigerator, and a washing machine. IoT devices may include sensors, smart meters, and the like. For example, the base station and the network may also be implemented as wireless devices, and the specific wireless device 200a may operate as a base station / network node to other wireless devices.

The wireless devices 100a to 100f may be connected to the network 300 through the base station 200. AI (Artificial Intelligence) technology may be applied to the wireless devices 100a to 100f, and the wireless devices 100a to 100f may be connected to the AI server 400 through the network 300. The network 300 may be configured using a 3G network, a 4G (eg, LTE) network, or a 5G (eg, NR) network. The wireless devices 100a to 100f may communicate with each other through the base station 200 / network 300, but may directly communicate (e.g. sidelink communication) without going through the base station / network. For example, the vehicles 100b-1 and 100b-2 may communicate directly (e.g. Vehicle to Vehicle (V2V) / Vehicle to everything (V2X) communication). In addition, the IoT device (eg, sensor) may directly communicate with other IoT devices (eg, sensor) or other wireless devices 100a to 100f.

Wireless communication /

connections

150a, 150b, and 150c may be achieved between the wireless devices 100a to 100f / base station 200 and the base station 200 / base station 200. Here, the wireless communication / connection is various wireless access such as uplink / downlink communication 150a and sidelink communication 150b (or D2D communication), base station communication 150c (eg relay, IAB (Integrated Access Backhaul)). It can be achieved through technology (eg, 5G NR). Through wireless communication /

connections

150a, 150b, 150c, wireless devices and base stations / wireless devices, base stations and base stations can transmit / receive radio signals to each other. For example, the wireless communication /

connections

150a, 150b, 150c can transmit / receive signals through various physical channels.To this end, based on various proposals of the present invention, for the transmission / reception of wireless signals, At least some of various configuration information setting processes, various signal processing processes (eg, channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), resource allocation processes, and the like may be performed.

Referring to FIG. 6, the wireless communication system may include a first device 610 and a second device 620.

The first device 610 is a base station, a network node, a transmitting terminal, a receiving terminal, a wireless device, a wireless communication device, a vehicle, a vehicle equipped with an autonomous driving function, a connected car, a drone (Unmanned Aerial Vehicle), UAV), AI (Artificial Intelligence) module, robot, Augmented Reality (AR) device, Virtual Reality (VR) device, Mixed Reality (MR) device, Hologram device, Public safety device, MTC device, IoT device, Medical device, Pin It may be a tech device (or financial device), a security device, a climate / environmental device, a device related to 5G services, or another device related to the fourth industrial revolution.

The second device 620 is a base station, a network node, a transmitting terminal, a receiving terminal, a wireless device, a wireless communication device, a vehicle, a vehicle equipped with an autonomous driving function, a connected car, a drone (Unmanned Aerial Vehicle), UAV), AI (Artificial Intelligence) module, robot, Augmented Reality (AR) device, Virtual Reality (VR) device, Mixed Reality (MR) device, Hologram device, Public safety device, MTC device, IoT device, Medical device, Pin It may be a tech device (or financial device), a security device, a climate / environmental device, a device related to 5G services, or another device related to the fourth industrial revolution.

For example, the terminal is a mobile phone, a smart phone, a laptop computer, a terminal for digital broadcasting, a personal digital assistants (PDA), a portable multimedia player (PMP), navigation, a slate PC, a tablet It may include a PC (tablet PC), ultrabook (ultrabook), wearable device (wearable device, for example, a watch-type terminal (smartwatch), glass-type terminal (smart glass), HMD (head mounted display), and the like. . For example, the HMD may be a display device worn on the head. For example, HMD can be used to implement VR, AR or MR.

For example, a drone may be a vehicle that does not ride and is flying by radio control signals. For example, the VR device may include a device that implements an object or background of a virtual world. For example, the AR device may include a device that is implemented by connecting an object or background of the virtual world to an object or background of the real world. For example, the MR device may include a device that fuses and implements an object or background of the virtual world in an object or background of the real world. For example, the hologram device may include a device that implements a 360-degree stereoscopic image by recording and reproducing stereoscopic information by utilizing the interference phenomenon of light generated when two laser lights called holography meet. For example, the public safety device may include a video relay device or a video device wearable on a user's body. For example, the MTC device and the IoT device may be devices that do not require direct human intervention or manipulation. For example, the MTC device and the IoT device may include a smart meter, a bending machine, a thermometer, a smart light bulb, a door lock, or various sensors. For example, a medical device may be a device used for the purpose of diagnosing, treating, alleviating, treating or preventing a disease. For example, a medical device may be a device used for the purpose of diagnosing, treating, reducing or correcting an injury or disorder. For example, a medical device may be a device used for the purpose of examining, replacing, or modifying a structure or function. For example, the medical device may be a device used to control pregnancy. For example, the medical device may include a medical device, a surgical device, a (in vitro) diagnostic device, a hearing aid, or a surgical device. For example, the security device may be a device installed in order to prevent a risk that may occur and to maintain safety. For example, the security device may be a camera, CCTV, recorder or black box. For example, the fintech device may be a device capable of providing financial services such as mobile payment. For example, the fintech device may include a payment device or a point of sales (POS). For example, a climate / environmental device may include a device that monitors or predicts the climate / environment.

The first device 610 may include at least one processor such as a processor 611, at least one memory such as a memory 612, and at least one transceiver such as a transceiver 613. The processor 611 may perform the functions, procedures, and / or methods described above. The processor 611 may perform one or more protocols. For example, the processor 611 may perform one or more layers of a radio interface protocol. The memory 612 is connected to the processor 611 and may store various types of information and / or instructions. The transceiver 613 may be connected to the processor 611 and controlled to transmit and receive wireless signals.

The second device 620 may include at least one processor such as the processor 621, at least one memory device such as the memory 622, and at least one transceiver such as the transceiver 623. The processor 621 may perform the functions, procedures, and / or methods described above. The processor 621 may implement one or more protocols. For example, the processor 621 may implement one or more layers of a radio interface protocol. The memory 622 is connected to the processor 621, and may store various types of information and / or instructions. The transceiver 623 is connected to the processor 621 and may be controlled to transmit and receive wireless signals.

The memory 612 and / or the memory 622 may be connected to each other inside or outside the processor 611 and / or the processor 621, and other processors may be connected through various technologies such as wired or wireless connections. It may be connected to.

The first device 610 and / or the second device 620 may have one or more antennas. For example, antenna 614 and / or antenna 624 may be configured to transmit and receive wireless signals.

Referring to FIG. 7, a wireless communication system includes a base station 710 and a plurality of terminals 720 located within a base station area. The base station can be represented as a transmitting device, and the terminal can be represented as a receiving device, and vice versa. The base station and the terminal include a processor (processor, 711,721), memory (memory, 714,724), one or more Tx / Rx RF modules (radio frequency module, 715,725), Tx processor (712,722), Rx processor (713,723), and antennas (716,726). Includes. The processor previously implements the salpin function, process and / or method. More specifically, in DL (base station to terminal communication), upper layer packets from the core network are provided to the processor 711. The processor implements the functionality of the L2 layer. In DL, the processor provides multiplexing between a logical channel and a transport channel and radio resource allocation to the terminal 720, and is responsible for signaling to the terminal. The transmit (TX) processor 712 implements various signal processing functions for the L1 layer (ie, physical layer). The signal processing function facilitates forward error correction (FEC) at the terminal and includes coding and interleaving. The coded and modulated symbols are divided into parallel streams, and each stream is mapped to an OFDM subcarrier, multiplexed with a reference signal (RS) in the time and / or frequency domain, and uses Inverse Fast Fourier Transform (IFFT). By combining them together, a physical channel carrying a time domain OFDMA symbol stream is generated. The OFDM stream is spatially precoded to produce a multiple spatial stream. Each spatial stream can be provided to a different antenna 716 through a separate Tx / Rx module (or transceiver 715). Each Tx / Rx module can modulate the RF carrier with each spatial stream for transmission. In the terminal, each Tx / Rx module (or transceiver 725) receives a signal through each antenna 726 of each Tx / Rx module. Each Tx / Rx module recovers information modulated with an RF carrier and provides it to a receiving (RX) processor 723. The RX processor implements various signal processing functions of layer 1. The RX processor may perform spatial processing on information to recover any spatial stream directed to the terminal. If multiple spatial streams are directed to the terminal, they can be combined into a single OFDMA symbol stream by multiple RX processors. The RX processor uses Fast Fourier Transform (FFT) to transform the OFDMA symbol stream from time domain to frequency domain. The frequency domain signal includes a separate OFDMA symbol stream for each subcarrier of the OFDM signal. The symbols and reference signals on each subcarrier are recovered and demodulated by determining the most probable signal placement points transmitted by the base station. These soft decisions may be based on channel estimates. Soft decisions are decoded and deinterleaved to recover the data and control signals originally transmitted by the base station on the physical channel. The data and control signals are provided to the processor 721.

UL (terminal to base station communication) is handled at base station 710 in a manner similar to that described with respect to receiver functionality at terminal 720. Each Tx / Rx module 725 receives a signal through each antenna 726. Each Tx / Rx module provides RF carriers and information to the RX processor 723. Processor 721 may be associated with memory 724 that stores program code and data. Memory can be referred to as a computer readable medium.

General LTE system to which the present specification can be applied

3GPP LTE / LTE-A supports a type 1 radio frame structure applicable to frequency division duplex (FDD) and a type 2 radio frame structure applicable to time division duplex (TDD).

In FIG. 8, the size of the radio frame in the time domain is expressed as a multiple of time units of T_s = 1 / (15000 * 2048). Downlink and uplink transmission are composed of radio frames having a period of T_f = 307200 * T_s = 10ms.

8A illustrates the structure of a type 1 radio frame. The type 1 radio frame can be applied to both full duplex and half duplex FDD.

A radio frame is composed of 10 subframes. One radio frame is composed of 20 slots of T_slot = 15360 * T_s = 0.5ms, and each slot is assigned an index from 0 to 19. One subframe is composed of two consecutive slots in the time domain, and subframe i is composed of slot 2i and slot 2i + 1. The time taken to transmit one subframe is called a transmission time interval (TTI). For example, one subframe may have a length of 1 ms, and a slot may have a length of 0.5 ms.

In FDD, uplink transmission and downlink transmission are classified in the frequency domain. While there is no restriction on full-duplex FDD, in half-duplex FDD operation, the UE cannot transmit and receive simultaneously.

One slot includes a plurality of orthogonal frequency division multiplexing (OFDM) symbols in the time domain and a plurality of resource blocks (RBs) in the frequency domain. Since 3GPP LTE uses OFDMA in the downlink, the OFDM symbol is for expressing one symbol period. The OFDM symbol may be referred to as one SC-FDMA symbol or symbol period. A resource block is a resource allocation unit and includes a plurality of consecutive subcarriers in one slot.

8 (b) shows a frame structure type 2 (frame structure type 2).

The type 2 radio frame is composed of two half frames each having a length of 153600 * T_s = 5ms. Each half frame consists of 5 subframes of 30720 * T_s = 1ms length.

In the type 2 frame structure of the TDD system, uplink-downlink configuration is a rule indicating whether uplink and downlink are allocated (or reserved) for all subframes.

Table 1 shows an uplink-downlink configuration.

[Table 1]

Referring to Table 1, for each subframe of a radio frame, 'D' represents a subframe for downlink transmission, 'U' represents a subframe for uplink transmission, and 'S' is DwPTS (Downlink Pilot) It represents a special subframe consisting of three fields: Time Slot (GP), Guard Period (GP), and Uplink Pilot Time Slot (UpPTS).

DwPTS is used for initial cell search, synchronization, or channel estimation at the UE. UpPTS is used to match channel estimation at the base station and uplink transmission synchronization of the terminal. GP is a section for removing interference caused in the uplink due to the multipath delay of the downlink signal between the uplink and the downlink.

Each subframe i is composed of slot 2i and slot 2i + 1 each of T_slot = 15360 * T_s = 0.5ms length.

The uplink-downlink configuration may be divided into seven types, and the positions and / or numbers of downlink subframes, special subframes, and uplink subframes are different for each configuration.

The time point of changing from downlink to uplink or the time point of switching from uplink to downlink is referred to as a switching point. Switch-point periodicity (Switch-point periodicity) refers to a period in which the uplink subframe and the downlink subframe are switched over the same period, and both 5ms or 10ms are supported. When the period of the 5ms downlink-uplink switching point is periodic, the special subframe S exists every half-frame, and when it has the period of the 5ms downlink-uplink switching point duration, it exists only in the first half-frame.

In all configurations,

subframes

0 and 5 and DwPTS are sections for downlink transmission only. UpPTS and subframe Subframe immediately following a subframe is always a section for uplink transmission.

The uplink-downlink configuration may be known to both the base station and the terminal as system information. The base station can inform the UE of the change of the uplink-downlink allocation state of the radio frame by transmitting only the index of the configuration information whenever the uplink-downlink configuration information changes. In addition, the configuration information is a kind of downlink control information and may be transmitted through a Physical Downlink Control Channel (PDCCH) like other scheduling information, and is commonly transmitted to all terminals in a cell through a broadcast channel as broadcast information. It may be.

Table 2 shows the configuration of the special subframe (DwPTS / GP / UpPTS length).

[Table 2]

The structure of the radio frame according to the example of FIG. 8 is only one example, and the number of subcarriers included in the radio frame, the number of slots included in the subframe, and the number of OFDM symbols included in the slot may be variously changed. Can be.

Referring to FIG. 9, one downlink slot includes a plurality of OFDM symbols in the time domain. Here, one downlink slot includes 7 OFDM symbols, and one resource block includes 12 subcarriers in the frequency domain by way of example, but is not limited thereto.

Each element on the resource grid is a resource element, and one resource block (RB) includes 12 × 7 resource elements. The number of resource blocks N ^ DL included in the downlink slot depends on the downlink transmission bandwidth.

The structure of the uplink slot may be the same as that of the downlink slot.

Referring to FIG. 10, up to three OFDM symbols in the first slot in a subframe are control regions to which control channels are allocated, and the remaining OFDM symbols are data regions to which Physical Downlink Shared Channel (PDSCH) is allocated. (data region). Examples of a downlink control channel used in 3GPP LTE include a Physical Control Format Indicator Channel (PCFICH), a Physical Downlink Control Channel (PDCCH), and a Physical Hybrid-ARQ Indicator Channel (PHICH).

The PCFICH is transmitted in the first OFDM symbol of the subframe, and carries information about the number of OFDM symbols (ie, the size of the control region) used for transmission of control channels in the subframe. The PHICH is a response channel for an uplink and carries an Acknowledgement (ACK) / Not-Acknowledgement (NACK) signal for a Hybrid Automatic Repeat Request (HARQ). Control information transmitted through the PDCCH is called downlink control information (DCI). The downlink control information includes uplink resource allocation information, downlink resource allocation information, or an uplink transmission (Tx) power control command for an arbitrary UE group.

PDCCH is a DL-SCH (Downlink Shared Channel) resource allocation and transmission format (this is also referred to as a downlink grant), UL-SCH (Uplink Shared Channel) resource allocation information (this is also referred to as an uplink grant), PCH ( Resource allocation for upper-layer control messages, such as paging information in a paging channel, system information in a DL-SCH, and random access response transmitted in a PDSCH, any terminal It can carry a set of transmission power control commands for individual terminals in a group, activation of voice over IP (VoIP), and the like. A plurality of PDCCHs can be transmitted within a control region, and the terminal can monitor a plurality of PDCCHs. The PDCCH is composed of a set of one or more consecutive control channel elements (CCEs). CCE is a logical allocation unit used to provide a coding rate according to a state of a radio channel to a PDCCH. The CCE corresponds to a plurality of resource element groups. The format of the PDCCH and the number of available PDCCH bits are determined according to an association between the number of CCEs and the coding rate provided by the CCEs.

The base station determines the PDCCH format according to the DCI to be transmitted to the terminal, and attaches CRC (Cyclic Redundancy Check) to the control information. The CRC is masked with a unique identifier (this is called a Radio Network Temporary Identifier (RNTI)) according to the owner or use of the PDCCH. If it is a PDCCH for a specific terminal, a unique identifier of the terminal, for example, a cell-RNTI (C-RNTI) may be masked to the CRC. Alternatively, if it is a PDCCH for a paging message, a paging indication identifier, for example, Paging-RNTI (P-RNTI) may be masked to the CRC. If the PDCCH is for system information, more specifically, a system information block (SIB), a system information identifier, a system information RNTI (SI-RNTI) may be masked in the CRC. In order to indicate a random access response that is a response to the transmission of the random access preamble of the terminal, a random access-RNTI (RA-RNTI) may be masked to the CRC.

Referring to FIG. 11, an uplink subframe may be divided into a control region and a data region in the frequency domain. A PUCCH (Physical Uplink Control Channel) carrying uplink control information is allocated to the control region. In the data area, a physical uplink shared channel (PUSCH) carrying user data is allocated. In order to maintain a single carrier characteristic, one UE does not transmit PUCCH and PUSCH at the same time.

A PUBCH for one UE is assigned a resource block (RB) pair in a subframe. RBs belonging to the RB pair occupy different subcarriers in each of the two slots. It is said that the RB pair allocated to the PUCCH is frequency hopping at a slot boundary.

General NR system to which the present specification can be applied

As more communication devices require a larger communication capacity, a need for an improved mobile broadband communication has emerged compared to a conventional radio access technology. In addition, massive MTC (Machine Type Communications), which provides various services anytime, anywhere by connecting multiple devices and objects, is also one of the major issues to be considered in next-generation communication. In addition, the design of a communication system considering services / terminals sensitive to reliability and latency is being discussed. As described above, the introduction of next-generation radio access technology in consideration of eMBB (enhanced mobile broadband communication), Mmtc (massive MTC), and URLLC (Ultra-Reliable and Low Latency Communication) is being discussed, and the technology is called NR for convenience in this specification. . NR is an expression showing an example of 5G radio access technology (RAT).

Next, a number of use cases will be described in more detail.

Artificial Intelligence (AI)

Robot

Self-Driving, Autonomous-Driving

EXtended Reality (XR)

The new RAT system including NR uses an OFDM transmission scheme or a similar transmission scheme. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system follows the existing numerology of LTE / LTE-A, but may have a larger system bandwidth (eg, 100 MHz). Or, one cell may support a plurality of neuromerology. That is, terminals operating with different numerology can coexist in one cell.

Numerology corresponds to one subcarrier spacing in the frequency domain. By scaling the reference subcarrier spacing to the integer N, different numerology can be defined.

Term Definition

eLTE eNB: The eLTE eNB is an evolution of the eNB that supports connectivity to EPC and NGC.

gNB: A node that supports NR as well as a connection with NGC.

New RAN: A radio access network that supports NR or E-UTRA or interacts with NGC.

Network slice: A network slice is a network defined by the operator to provide an optimized solution for specific market scenarios that require specific requirements along with end-to-end coverage.

Network function: A network function is a logical node within a network infrastructure with well-defined external interfaces and well-defined functional behavior.

NG-C: Control plane interface used for the NG2 reference point between the new RAN and NGC.

NG-U: User plane interface used for NG3 reference point between new RAN and NGC.

Non-standalone NR: Deployment configuration where gNB requires LTE eNB as an anchor for control plane connection to EPC or eLTE eNB as an anchor for control plane connection to NGC.

Non-standalone E-UTRA: Deployment configuration where eLTE eNB requires gNB as an anchor for control plane connection to NGC.

User plane gateway: The endpoint of the NG-U interface.

System general

Referring to FIG. 12, the NG-RAN consists of NG-RA user planes (new AS sublayer / PDCP / RLC / MAC / PHY) and gNBs that provide control plane (RRC) protocol termination for UE (User Equipment). do.

The gNBs are interconnected through an Xn interface.

The gNB is also connected to the NGC through the NG interface.

More specifically, the gNB is connected to an Access and Mobility Management Function (AMF) through an N2 interface and a User Plane Function (UPF) through an N3 interface.

NR (New Rat) Numerology and Frame Structure

In the NR system, multiple numerologies may be supported. Here, the numerology may be defined by subcarrier spacing and CP (Cyclic Prefix) overhead. At this time, a plurality of subcarrier intervals is the default subcarrier interval N (or,

) Can be derived by scaling. Further, even if it is assumed that a very low subcarrier spacing is not used at a very high carrier frequency, the numerology used can be selected independently of the frequency band.

In addition, in the NR system, various frame structures according to a number of pneumatics may be supported.

Hereinafter, an orthogonal frequency division multiplexing (OFDM) numerology and a frame structure that can be considered in an NR system will be described.

A number of OFDM neurology supported in the NR system can be defined as shown in Table 3.

[Table 3]

With respect to the frame structure in the NR system, the size of various fields in the time domain is

It is expressed as a multiple of the unit of time. From here,

ego,

to be. Downlink (downlink) and uplink (uplink) transmission is

It consists of a radio frame (radio frame) having a section of. Here, each radio frame is

It consists of 10 subframes (subframes) having an interval of. In this case, there may be one set of frames for uplink and one set of frames for downlink.

As shown in FIG. 13, transmission of uplink frame number i from a user equipment (UE) is greater than the start of a corresponding downlink frame at the corresponding terminal.

You have to start earlier.

New Merology

For, slots are within a subframe

Numbered in increasing order, within the radio frame

It is numbered in increasing order. One slot

Consisting of consecutive OFDM symbols of,

Is determined according to the numerology and slot configuration used. Slot in subframe

Start of OFDM symbol in the same subframe

It is aligned with the start of time.

Not all terminals can transmit and receive at the same time, which means that not all OFDM symbols in a downlink slot or an uplink slot cannot be used.

Table 4 shows the number of OFDM symbols per slot in a normal CP (

), The number of slots per radio frame (

), Number of slots per subframe (

), And Table 5 shows the number of OFDM symbols per slot, the number of slots per radio frame, and the number of slots per subframe in the extended CP.

[Table 4]

[Table 5]

14 shows an example of a frame structure in an NR system.

14 is for convenience of description only and does not limit the scope of the present specification.

For Table 5,

= 2, that is, as an example of a case where the subcarrier spacing (SCS) is 60 kHz, referring to Table 4, one subframe (or frame) may include four slots, as shown in FIG. 1 subframe = {1,2,4} slots is an example, and the number of slot (s) that may be included in one subframe may be defined as shown in Table 2.

Also, a mini-slot may consist of 2, 4 or 7 symbols, or more or less symbols.

With respect to physical resources in the NR system, an antenna port, a resource grid, a resource element, a resource block, a carrier part, etc. Can be considered.

Hereinafter, the physical resources that can be considered in the NR system will be described in detail.

First, with respect to the antenna port, the antenna port is defined such that the channel on which the symbol on the antenna port is carried can be deduced from the channel on which the other symbol on the same antenna port is carried. If the large-scale property of a channel carrying a symbol on one antenna port can be inferred from a channel carrying a symbol on another antenna port, the two antenna ports are QC / QCL (quasi co-located or quasi co-location). Here, the wide-scale characteristics include one or more of delay spread, doppler spread, frequency shift, average received power, and received timing.

Referring to Figure 15, the resource grid is on the frequency domain

It is configured by subcarriers, one subframe is composed of 14 · 2μ OFDM symbols as an example, but is not limited thereto.

In the NR system, the transmitted signal is

One or more resource grids consisting of subcarriers and

It is described by the OFDM symbols of. From here,

to be. remind

Denotes a maximum transmission bandwidth, which may vary between uplink and downlink as well as numerology.

In this case, as shown in Fig. 16, the neuromerology

And one resource grid for each antenna port p.

New Merology

And each element of the resource grid for the antenna port p is referred to as a resource element, an index pair

It is uniquely identified by. From here,

Is an index on the frequency domain,

Indicates the position of the symbol in the subframe. When referring to a resource element in a slot, an index pair

Is used. From here,

to be.

New Merology

And resource elements for antenna port p

Is the complex value

Corresponds to If there is no risk of confusion, or if a specific antenna port or numerology is not specified, the indexes p and

Can be dropped, resulting in a complex value

or

Can be

In addition, a physical resource block (physical resource block) on the frequency domain

It is defined as consecutive subcarriers.

Point A serves as a common reference point of the resource block grid and can be obtained as follows.

-OffsetToPointA for PCell downlink indicates the frequency offset between the lowest sub-carrier and point A of the lowest resource block overlapping the SS / PBCH block used by the UE for initial cell selection, 15 kHz subcarrier spacing for FR1 and Expressed in resource block units assuming a 60 kHz subcarrier spacing for FR2;

-absoluteFrequencyPointA represents the frequency-position of point A expressed as in an absolute radio-frequency channel number (ARFCN).

Common resource blocks set the subcarrier interval

It is numbered upward from 0 in the frequency domain for.

Subcarrier spacing setting

The center of subcarrier 0 of the common resource block 0 for 'point A' coincides with 'point A'. Common resource block number in frequency domain

And subcarrier spacing settings

The resource element (k, l) for can be given as in Equation 1 below.

[Equation 1]

Here, k can be defined relative to point A such that k = 0 corresponds to a subcarrier centered on point A. Physical resource blocks start from 0 within a bandwidth part (BWP).

Is numbered, i is the number of the BWP. Physical resource block in BWP i

And common resource blocks

The relationship between can be given by Equation 2 below.

[Equation 2]

From here,

May be a common resource block in which the BWP starts relative to the common resource block 0.

On the other hand, the PRB grid of each neurology supported by the carrier, the BWP setting in each carrier of DL / UL (supports up to 4 BWP), CBG (code block group) setting, TPC (Transmission power control) per cell group, The HARQ process, scrambling / sequence related parameters, etc. can be set in the carrier level. Control resource set (set per cell, but associated per BWP), parameters related to resource allocation and DM-RS setup, CSI-RS related parameters, SRS resource set, HARQ-ACK and SR ( schedule request) resources, a set UL grant, etc. may be set in the BWP stage.

MTC (Machine Type Communication)

MTC (Machine Type Communication) is an application that does not require much throughput that can be applied to M2M (Machine-to-Machine) or IoT (Internet-of-Things), and is an IoT service in 3GPP (3rd Generation Partnership Project) It refers to the communication technology adopted to meet the requirements of.

The MTC may be implemented to satisfy the criteria of (i) low cost and low complexity, (ii) enhanced coverage, and (iii) low power consumption.

In 3GPP, MTC has been applied since release 10, and the characteristics of MTC added for each release of 3GPP are briefly reviewed.

First, the MTC described in 3GPP release 10 and release 11 relates to a load control method.

The load control method is to prevent IoT (or M2M) devices from suddenly loading the base station.

More specifically, in the case of release 10, the base station relates to a method of controlling the load by disconnecting the connected IoT devices when a load occurs, and in the case of release 11, the base station broadcasts the same as SIB14. It relates to a method of blocking a connection to a terminal in advance by notifying the terminal in advance to access later.

For Release 12, features for low cost MTC were added, and UE category 0 was newly defined for this. The UE category is an index indicating how much data the terminal can handle in the communication modem.

That is, the UE category 0 UE reduces the baseband and RF complexity of the UE by using a half duplex operation with a reduced peak data rate, a relaxed RF requirement, and a single receive antenna.

In Release 13, a technology called enhanced MTC (eMTC) was introduced, and it is possible to lower the cost and power consumption by operating only at 1.08MHz, which is the minimum frequency bandwidth supported by legacy LTE.

The contents described below are mainly features related to eMTC, but may be equally applied to MTC to be applied to MTC, eMTC, 5G (or NR) unless otherwise specified. Hereinafter, for convenience of description, it will be collectively described as MTC.

Therefore, the MTC to be described later is eMTC (enhanced MTC), LTE-M1 / M2, BL (Bandwidth reduced low complexity) / CE (coverage enhanced), non-BL UE (in enhanced coverage), NR MTC, enhanced BL / CE, etc. Likewise, it may be referred to as another term. That is, the term MTC can be replaced with a term to be defined in the future 3GPP standard.

1) MTC general features

(1) MTC operates only in a specific system bandwidth (or channel bandwidth).

The specific system bandwidth may use 6RB of legacy LTE as shown in Table 6 below, and may be defined in consideration of the frequency range of the NR and subcarrier spacing (SCS) defined in Tables 7 to 9. The specific system bandwidth may be expressed as a narrowband (NB). For reference, Legacy LTE means a part described in 3GPP standard other than MTC. Preferably, in NR, MTC may operate using RBs corresponding to the lowest system bandwidths of Tables 8 and 9 below as in legacy LTE. Alternatively, the MTC in the NR may operate in at least one bandwidth part (BWP) or may operate in a specific band of the BWP.

[Table 6]

Table 7 is a table showing a frequency range (FR) defined in NR.

[Table 7]

Table 8 is a table showing an example of the maximum transmission bandwidth configuration (NRB) for the channel bandwidth and SCS in FR 1 of the NR.

[Table 8]

Table 9 is a table showing an example of a maximum transmission bandwidth configuration (NRB) for channel bandwidth and SCS in FR 2 of NR.

[Table 9]

The MTC narrowband (NB) will be examined in more detail.

MTC follows a narrowband operation to transmit and receive physical channels and signals, and the maximum channel bandwidth is reduced to 1.08 MHz or 6 (LTE) RBs.

The narrowband may be used as a reference unit for resource allocation units of some channels of downlink and uplink, and the physical location of each narrowband in the frequency domain may be defined differently according to system bandwidth.

The bandwidth of 1.08 MHz defined in MTC is defined to allow the MTC terminal to follow the same cell search and random access procedure as the legacy terminal.

MTC can be supported by cells with much greater bandwidth than 1.08 MHz (eg 10 MHz), but the physical channels and signals transmitted / received by MTC are always limited to 1.08 MHz.

The system having a much larger bandwidth may be a legacy LTE, NR system, 5G system, or the like.

Narrowband is defined as six non-overlapping consecutive physical resource blocks in the frequency domain.

if

In the case of, wideband is defined as four non-overlapping narrowbands in the frequency domain. if

If it is,

And single wideband

It consists of non-overlapping narrowband (s).

For example, in the case of a 10 MHz channel (50 RBs), 8 non-overlapping narrowbands are defined.

17 shows an example of narrowband operation and frequency diversity.

17 (a) is a diagram showing an example of a narrowband operation, and FIG. 17 (b) is a diagram showing an example of repetition with RF retuning.

Referring to (b) of FIG. 17, frequency diversity by RF retuning will be described.

Due to narrowband RF, single antenna and limited mobility, MTC supports limited frequency, spatial and temporal diversity. To reduce the effects of fading and outage, frequency hopping is supported between different narrowbands by RF retuning.

This frequency hopping is applied to different uplink and downlink physical channels when repetition is possible.

For example, when 32 subframes are used for PDSCH transmission, the first 16 subframes may be transmitted on the first narrowband. At this time, the RF front-end is retune to another narrowband, and the remaining 16 subframes are transmitted on the second narrowband.

The narrowband of the MTC can be set by system information or downlink control information (DCI).

(2) MTC operates in half duplex mode and uses limited (or reduced) maximum transmission power.

(3) MTC does not use a channel (defined in legacy LTE or NR) that must be distributed over the entire system bandwidth of legacy LTE or NR.

For example, legacy LTE channels not used for MTC are PCFICH, PHICH, and PDCCH.

Therefore, the MTC cannot monitor the above channels and defines a new control channel, MPDCCH (MTC PDCCH).

MPDCCH spans up to 6 RBs in the frequency domain and one subframe in the time domain.

MPDCCH is similar to EPDCCH, and additionally supports a common search space for paging and random access.

The MPDCCH is similar to the concept of E-PDCCH used in legacy LTE.

(4) MTC uses a newly defined DCI format, and may be, for example, DCI formats 6-0A, 6-0B, 6-1A, 6-1B, 6-2, and the like.

(5) MTC is PBCH (physical broadcast channel), PRACH (physical random access channel), M-PDCCH (MTC physical downlink control channel), PDSCH (physical downlink shared channel), PUCCH (physical uplink control channel), PUSCH (physical uplink shared channel). The MTC repetitive transmission can decode the MTC channel even when the signal quality or power is very poor, such as in a poor environment such as a basement, which can increase cell radius and effect signal penetration. The MTC may support only a limited number of transmission modes (TM) capable of operating in a single layer (or single antenna) or may support a channel or reference signal (RS) capable of operating in a single layer. . For example, the transmission mode in which the MTC can operate may be

TM

1, 2, 6 or 9.

(6) HARQ retransmission of MTC is adaptive and asynchronous, and is based on a new scheduling assignment received in MPDCCH.

(7) PDSCH scheduling (DCI) and PDSCH transmission in MTC occur in different subframes (cross subframe scheduling).

(8) All resource allocation information (subframe, transport block size (TBS), subband index) for SIB1 decoding is determined by MIB parameters, and no control channel is used for STC1 decoding of MTC.

(9) All resource allocation information (subframe, TBS, subband index) for SIB2 decoding is determined by several SIB1 parameters, and no control channel for SIB2 decoding of MTC is used.

(10) MTC supports extended paging (DRX) cycle.

(11) MTC can use the same as the primary synchronization signal (PSS) / secondary synchronization signal (SSS) / common reference signal (CRS) used in legacy LTE or NR. In the case of NR, PSS / SSS is transmitted in SS block (or SS / PBCH block or SSB) units, and TRS (tracking RS) may be used for the same purpose as CRS. That is, TRS is a cell-specific RS, and can be used for frequency / time tracking.

2) MTC operation mode and level

Next, the MTC operation mode and level will be described. MTC is classified into two operation modes (first mode and second mode) and four different levels to improve coverage, and may be as shown in Table 10 below.

The MTC operation mode is referred to as CE Mode, in which case the first mode may be referred to as CE Mode A and the second mode as CE Mode B.

Table 10

The first mode is defined for small mobility enhancement with full mobility and CSI (channel state information) feedback, so that there is no repetition or fewer repetitions. The operation of the first mode may be the same as the operation range of UE category 1. The second mode is defined for UEs with extremely poor coverage conditions that support CSI feedback and limited mobility, and a large number of repetitive transmissions are defined. The second mode provides coverage enhancement of up to 15 dB based on the range of UE category 1. Each level of MTC is defined differently in RACH and paging procedure.

Let's look at the MTC operation mode and how each level is determined.

The MTC operation mode is determined by the base station, and each level is determined by the MTC terminal. Specifically, the base station transmits RRC signaling including information on the MTC operation mode to the terminal. Here, the RRC signaling may be an RRC connection setup message, an RRC connection reconfiguration message, or an RRC connection reestablishment message. Here, the term of the message may be expressed as an information element (IE).

Thereafter, the MTC terminal determines the level in each operation mode, and transmits the determined level to the base station. Specifically, the MTC terminal determines the level in the operation mode based on the measured channel quality (eg, RSRP, RSRQ, or SINR), and determines the base station using PRACH resources (frequency, time, preamble) corresponding to the determined level. Inform the level.

3) MTC guard period

Like Salpin, MTC operates in narrowband. The position of the narrowband may be different for each specific time unit (eg, subframe or slot). The MTC terminal tunes to a different frequency in all time units. Therefore, a certain time is required for all frequency retuning, and this constant time is defined as the guard period of the MTC. That is, the guard period is required when transitioning from one time unit to the next time unit, and transmission and reception do not occur during the corresponding period.

The guard period is defined differently depending on whether it is a downlink or an uplink, and is differently defined according to the situation of the downlink or uplink. First, the guard period defined in the uplink is defined differently according to characteristics of data carried by the first time unit (time unit N) and the second time unit (time unit N + 1). Next, the guard period of the downlink is (1) first downlink narrowband center frequency and second narrowband center frequency are different, and (2) in TDD, first uplink narrowband center frequency and second downlink center frequency are different.

Looking at the MTC guard period defined in Legacy LTE, at most for retuning the Tx-Tx frequency between two consecutive subframes

A guard period of SC-FDMA symbols is generated. If the upper layer parameter ce-RetuningSymbols is set,

Is the same as ce-RetuningSymbols, otherwise

= 2. In addition, for the MTC terminal configured with the upper layer parameter srs-UpPtsAdd, a guard period of the maximum SC-FDMA symbol is generated for Tx-Tx frequency retuning between the first special subframe for the frame structure type 2 and the second uplink subframe. .

When the power is turned off again or the power is turned off again, the MTC terminal newly entering the cell performs an initial cell search operation such as synchronizing with the base station in step S1101. To this end, the MTC terminal receives a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) from a base station, synchronizes with the base station, and acquires information such as a cell ID (identifier). The PSS / SSS used for the initial cell search operation of the MTC may be a PSS / SSS of legacy LTE, a resynchronization signal (RSS), or the like.

Thereafter, the MTC terminal may acquire a physical broadcast channel (PBCH) signal from a base station to obtain intra-cell broadcast information.

Meanwhile, the MTC terminal may check a downlink channel state by receiving a downlink reference signal (DL RS) in an initial cell search step. The broadcast information transmitted through the PBCH is a master information block (MIB), and in the MTC, the MIB is a subframe different from the first slot of the subframe # 0 of the radio frame (subframe # 9 for FDD and subframe # 5 for TDD). Is repeated in

PBCH repetition is performed by repeating exactly the same constellation point in different OFDM symbols so that it can be used for initial frequency error estimation even before attempting PBCH decoding.

19 (a) is a diagram showing an example of a frequency error estimation method for a repeat pattern, a normal CP, and repeated symbols for subframe # 0 in FDD, and FIG. 19 (b) shows SIB- on a broadband LTE channel. An example of BR transmission is shown.

In the MIB, five reserved bits are used in the MTC to transmit scheduling information for a new system information block for bandwidth reduced device (SIB1-BR) including time / frequency location and transport block size.

The SIB-BR is transmitted directly on the PDSCH without any control channel associated with it.

SIB-BR remains unchanged in 512 radio frames (5120 ms) to allow multiple subframes to be combined.

Table 11 is a table showing an example of MIB.

[Table 11]

In Table 11, the schedulingInfoSIB1-BR field indicates an index for a table defining SystemInformationBlockType1-BR scheduling information, and value 0 means that SystemInformationBlockType1-BR is not scheduled. The overall functions and information carried by SystemInformationBlockType1-BR (or SIB1-BR) are similar to legacy LTE's SIB1. The contents of SIB1-BR can be classified into (1) PLMN, (2) cell selection criteria, (3) SIB2 and scheduling information for other SIBs.

After completing the initial cell search, the MTC terminal may acquire PDSCH according to the MPDCCH and MPDCCH information in step S1102 to obtain more specific system information. MPDCCH is (1) very similar to EPDCCH, carries common and UE specific signaling, (2) can be transmitted only once or repeatedly (the number of repetitions is set by higher layer signaling), (3) Multiple MPDCCHs are supported and the UE monitors a set of MPDCCHs, (4) formed by combining eCCE (enhanced control channel element), each eCCE includes a set of resource elements, and (5) RA-RNTI ( Radio Network Temporary Identifier (SI), SI-RNTI, P-RNTI, C-RNTI, temporary C-RNTI and semi-persistent scheduling (SPS) C-RNTI are supported.

Thereafter, the MTC terminal may perform a random access procedure, such as steps S1103 to S1106, in order to complete access to the base station. The basic configuration related to the RACH procedure is transmitted by SIB2. In addition, SIB2 includes parameters related to paging. Paging Occasion (PO) is a subframe in which P-RNTI can be transmitted on MPCCH. When P-RNTI PDCCH is repeatedly transmitted, PO refers to a start subframe of MPDCCH repetition. The paging frame (PF) is one radio frame, and may include one or multiple POs. When DRX is used, the MTC terminal monitors only one PO per DRX cycle. Paging NarrowBand (PNB) is a narrowband, and the MTC terminal performs paging message reception.

To this end, the MTC terminal may transmit a preamble through a physical random access channel (PRACH) (S1103), and receive a response message (RAR) for the preamble through MPDCCH and a corresponding PDSCH ( S1104). In the case of contention-based random access, the MTC terminal may perform a contention resolution procedure such as transmission of an additional PRACH signal (S1105) and reception of an MPDCCH signal and a corresponding PDSCH signal (S1106). In MTC, signals and / or messages (Msg 1, Msg 2, Msg 3, Msg 4) transmitted in the RACH procedure may be repeatedly transmitted, and this repetition pattern is set differently according to CE level. Msg 1 means PRACH preamble, Msg 2 means random access response (RAR), Msg 3 means UL transmission of MTC terminal for RAR, and Msg 4 means DL transmission of base station for Msg 3 can do.

For random access, signaling for different PRACH resources and different CE levels is supported. This provides the same control of the near-far effect on the PRACH by grouping UEs experiencing similar path loss together. Up to four different PRACH resources may be signaled to the MTC terminal.

The MTC terminal estimates RSRP using downlink RS (eg, CRS, CSI-RS, TRS, etc.), and selects one of the resources for random access based on the measurement result. Each of the four random access resources is related to the number of repetitions for PRACH and the number of repetitions for RAR (random access response).

Therefore, a bad coverage MTC terminal needs a large number of repetitions to be successfully detected by the base station, and needs to receive an RAR having a corresponding repetition number to satisfy their coverage level.

Search spaces for RAR and contention resolution messages are also defined in system information, and are independent for each coverage level.

In addition, the PRACH waveform used in MTC is the same as the PRACH waveform used in legacy LTE (eg, OFDM and Zadof-Chu sequences).

The MTC terminal performing the above-described procedure is a general uplink / downlink signal transmission procedure, and then receives the MPDCCH signal and / or the PDSCH signal (S1107) and the physical uplink shared channel (PUSCH) signal and / or the physical uplink control. The transmission of a channel (PUCCH) signal (S1108) may be performed. The control information transmitted by the MTC terminal to the base station is collectively referred to as uplink control information (UCI). The UCI may include HARQ-ACK / NACK, scheduling request (SR), channel quality indicator (CQI), precoding matrix indicator (PMI), rank indication (RI) information, and the like. have.

When the RRC connection to the MTC terminal is established, the MTC terminal blindly decodes MPDCCH in a search space set to obtain uplink and downlink data allocation.

MTC uses all OFDM symbols available in a subframe to transmit DCI. Therefore, time domain multiplexing between a control channel and a data channel in the same subframe is impossible. That is, as previously discussed, cross-subframe scheduling between a control channel and a data channel is possible.

MPDCCH having the last repetition in subframe #N schedules PDSCH allocation in subframe # N + 2.

The DCI transmitted by the MPDCCH provides information on how much the MPDCCH is repeated so that the MTC terminal knows when PDSCH transmission starts.

PDSCH allocation may be performed in different narrowbands. Therefore, the MTC terminal needs to retune before decoding the PDSCH allocation.

For uplink data transmission, scheduling follows the same timing as legacy LTE. Here, the last MPDCCH in subframe #N schedules PUSCH transmission starting from subframe # N + 4.

Legacy LTE allocation is scheduled using the PDCCH, which uses the first OFDM symbols in each subframe, and PDSCH is scheduled in the same subframe as the subframe in which the PDCCH is received.

In contrast, the MTC PDSCH is scheduled cross-subframe, and one subframe is defined between the MPDCCH and the PDSCH to allow MPDCCH decoding and RF retuning.

The MTC control channel and data channels can be repeated over a large number of subframes with up to 256 subframes for MPDCCH and up to 2048 subframes for PDSCH to be decoded under extreme coverage conditions.

NB-IoT (Narrowband-Internet of Things)

NB-IoT provides low complexity and low power consumption through system bandwidth (system BW) corresponding to 1 PRB (Physical Resource Block) of a wireless communication system (eg, LTE system, NR system, etc.). It can mean a system to support.

Here, NB-IoT may be referred to by other terms such as NB-LTE, NB-IoT enhancement, enhanced NB-IoT, further enhanced NB-IoT, NB-NR, and the like. That is, NB-IoT may be defined or replaced by a term to be defined in the 3GPP standard. Hereinafter, for convenience of description, it will be collectively expressed as 'NB-IoT'.

NB-IoT mainly supports a device (or terminal) such as machine-type communication (MTC) in a cellular system, and may be used as a communication method for implementing IoT (ie, Internet of Things). . At this time, by allocating 1 PRB of the existing system band for NB-IoT, there is an advantage that the frequency can be efficiently used. In addition, in the case of NB-IoT, since each terminal recognizes a single PRB (single PRB) as each carrier, PRBs and carriers referred to in this specification may be interpreted in the same sense.

Hereinafter, the frame structure, physical channel, multi-carrier operation, operation mode, and general signal transmission / reception related to the NB-IoT in the present specification are described in consideration of the case of the existing LTE system, Needless to say, the next generation system (eg, NR system, etc.) can also be extended. In addition, the contents related to NB-IoT in the present specification may be extended to MTC (Machine Type Communication) that aims for similar technical purposes (eg, low-power, low-cost, improved coverage, etc.).

1) NB-IoT frame structure and physical resources

First, the NB-IoT frame structure may be set differently according to subcarrier spacing. Specifically, FIG. 21 shows an example of a frame structure when the subcarrier spacing is 15 kHz, and FIG. 22 shows an example of a frame structure when the subcarrier spacing is 3.75 kHz. However, the NB-IoT frame structure is not limited to this, and it is needless to say that the NB-IoT for other subcarrier intervals (eg, 30 kHz, etc.) may be considered by varying time / frequency units.

In addition, although the NB-IoT frame structure based on the LTE system frame structure is described as an example in this specification, it is for convenience of description and is not limited thereto, and the method described herein is a next-generation system (eg, an NR system). Of course, it can be extended to NB-IoT based on the frame structure.

21 and 22 show examples of the NR-IoT frame structure.

Referring to FIG. 21, the NB-IoT frame structure for a 15 kHz subcarrier interval may be set to be the same as the frame structure of the legacy system (ie, LTE system) described above. That is, the 10ms NB-IoT frame includes 10 1ms NB-IoT subframes, and the 1ms NB-IoT subframe includes 2 0.5ms NB-IoT slots. In addition, each 0.5ms NB-IoT may include 7 OFDM symbols.

Alternatively, referring to FIG. 22, a 10ms NB-IoT frame includes 5 2ms NB-IoT subframes, and a 2ms NB-IoT subframe includes 7 OFDM symbols and one guard period (Guard Period, GP) It may include. In addition, the 2ms NB-IoT subframe may be represented by an NB-IoT slot or an NB-IoT resource unit (RU).

Next, the physical resources of the NB-IoT for each of the downlink and uplink are described.

First, the physical resource of the NB-IoT downlink is physical of another wireless communication system (eg, LTE system, NR system, etc.), except that the system bandwidth is a certain number of RBs (eg, one RB, that is, 180 kHz). It can be set with reference to resources. For example, as described above, when the NB-IoT downlink supports only a 15 kHz subcarrier interval, the physical resource of the NB-IoT downlink is 1 RB in the frequency domain of the resource grid of the LTE system shown in FIG. , 1 PRB).

Next, even in the case of NB-IoT uplink physical resources, the system bandwidth may be limited to one RB as in the downlink case. For example, as described above, when the NB-IoT uplink supports 15 kHz and 3.75 kHz subcarrier spacing, the resource grid for the NB-IoT uplink may be represented as shown in FIG. 23.

23 shows an example of a resource grid for NB-IoT uplink.

At this time, the number of subcarriers in the uplink band in Figure 23

And slot duration

Can be given as shown in Table 12 below.

Table 12

In addition, the resource unit (RU) of the NB-IoT uplink is composed of SC-FDMA symbols in the time domain, and in the frequency domain

It may be composed of consecutive subcarriers. Illero,

And

May be given by Table 13 below for frame structure type 1 (ie, FDD), and may be given by Table 14 for frame structure type 2 (ie, TDD).

[Table 13]

Table 14

2) Physical channel of NB-IoT

The base station and / or terminal supporting NB-IoT may be configured to transmit and receive physical channels and / or physical signals separately set from the existing system. Hereinafter, specific content related to physical channels and / or physical signals supported by the NB-IoT will be described.

First, the downlink of the NB-IoT system will be described. Orthogonal frequency division multiple access (OFDMA) scheme may be applied to the NB-IoT downlink based on a subcarrier interval of 15 kHz. Through this, orthogonality between subcarriers is provided to effectively support co-existence with an existing system (eg, LTE system, NR system).

The physical channel of the NB-IoT system may be expressed in a form in which 'N (Narrowband)' is added to distinguish it from the existing system. For example, a downlink physical channel is defined as a narrowband physical broadcast channel (NPBCH), a narrowband physical downlink control channel (NPDCCH), a narrowband physical downlink shared channel (NPDSCH), and the downlink physical signal is a narrowband primary synchronization signal (NPSS). ), NSSS (Narrowband Secondary Synchronization Signal), NRS (Narrowband Reference Signal), NPRS (Narrowband Positioning Reference Signal), NWUS (Narrowband Wake Up Signal).

In general, the downlink physical channel and physical signal of the NB-IoT described above may be configured to be transmitted based on a time domain multiplexing scheme and / or a frequency domain multiplexing scheme.

In addition, characteristically, in the case of NPBCH, NPDCCH, NPDSCH, etc., which are downlink channels of an NB-IoT system, repetition transmission may be performed for coverage enhancement.

In addition, NB-IoT uses a newly defined DCI format (DCI format), and for example, DCI format for NB-IoT may be defined as DCI format N0, DCI format N1, DCI format N2, and the like.

Next, the uplink of the NB-IoT system will be described. SC-FDMA (Single Carrier Frequency Divison Multiple Access) method may be applied to the NB-IoT uplink based on a subcarrier interval of 15 kHz or 3.75 kHz. In the uplink of NB-IoT, multi-tone transmission and single-tone transmission may be supported. In one example, multi-tone transmission is supported only for subcarrier spacing of 15 kHz, and single-tone transmission may be supported for subcarrier spacing of 15 kHz and 3.75 kHz.

As mentioned in the downlink section, the physical channel of the NB-IoT system may be expressed in a form in which 'N (Narrowband)' is added to distinguish it from the existing system. For example, the uplink physical channel may be defined as a narrowband physical random access channel (NPRACH) and a narrowband physical uplink shared channel (NPUSCH), and the uplink physical signal may be defined as a narrowband demodulation reference signal (NDMRS).

Here, the NPUSCH may consist of NPUSCH format 1, NPUSCH format 2, and so on. As an example, NPUSCH format 1 is used for UL-SCH transmission (or transport), and NPUSCH format 2 can be used for transmission of uplink control information such as HARQ ACK signaling.

In addition, characteristically, in the case of NPRACH, which is a downlink channel of the NB-IoT system, repetition transmission may be performed for coverage enhancement. In this case, repetitive transmission may be performed by applying frequency hopping.

3) NB-IoT multi-carrier operation

Next, the multi-carrier operation of the NB-IoT will be described. The multi-carrier operation may mean that a plurality of carriers having different uses (ie, different types) are used when a base station and / or a terminal transmit and receive channels and / or signals to each other in an NB-IoT.

In general, NB-IoT can operate in a multi-carrier mode as described above. At this time, the carrier in the NB-IoT is an anchor type carrier (ie, an anchor carrier, an anchor PRB) and a non-anchor type carrier (ie, a non-anchor type carrier). It can be defined as an anchor carrier (non-anchor carrier), non-anchor PRB.

An anchor carrier may mean a carrier that transmits NPSS, NSSS, NPBCH, and NPDSCH for system information block (N-SIB) for initial access from the base station point of view. That is, in NB-IoT, a carrier for initial connection may be referred to as an anchor carrier, and other (s) may be referred to as a non-anchor carrier. At this time, there may be only one anchor carrier on the system, or there may be multiple anchor carriers.

4) Operation mode of NB-IoT

Next, the operation mode of the NB-IoT will be described. Three operation modes may be supported in the NB-IoT system. 23 shows an example of operation modes supported in the NB-IoT system. Although the operation mode of the NB-IoT is described based on the LTE band in this specification, it is only for convenience of description and can be extendedly applied to a band of another system (for example, an NR system band).

Specifically, FIG. 23 (a) shows an example of an in-band system, FIG. 23 (b) shows an example of a guard-band system, and FIG. 23 (c) ) Represents an example of a stand-alone system. At this time, the in-band system (In-band system) is in-band mode (In-band mode), the guard-band system (Guard-band system) is a guard-band mode (Guard-band mode), stand-alone The system (stand-alone system) may be expressed in a stand-alone mode.

The in-band system may refer to a system or mode in which a specific 1 RB (ie PRB) in the (legacy) LTE band is used for NB-IoT. The in-band system may be operated by allocating some resource blocks of the LTE system carrier.

The guard-band system may refer to a system or mode using NB-IoT in a space reserved for a guard band of a (legacy) LTE band. The guard-band system may be operated by assigning a guard-band of an LTE carrier that is not used as a resource block in the LTE system. In one example, the (legacy) LTE band may be set to have a Guard-band of at least 100 kHz at the end of each LTE band. To use 200 kHz, two non-contiguous Guard-bands can be used.

As described above, the In-band system and the Guard-band system can be operated in a structure in which NB-IoT coexists in a (legacy) LTE band.

In contrast, a standalone system may refer to a system or mode configured independently from the (legacy) LTE band. The standalone system may be operated by separately allocating a frequency band used in the GERAN (GSM EDGE Radio Access Network) (eg, a future reassigned GSM carrier).

The three operation modes described above may be independently operated, or two or more operation modes may be combined to operate.

5) General signal transmission / reception procedure of NB-IoT

In a wireless communication system, an NB-IoT terminal receives information through a downlink (DL) from a base station, and the NB-IoT terminal can transmit information through an uplink (UL) to the base station. In other words, in a wireless communication system, the base station transmits information to the NB-IoT terminal through downlink, and the base station can receive information from the NB-IoT terminal through uplink.

The information transmitted and received by the base station and the NB-IoT terminal includes data and various control information, and various physical channels may exist depending on the type / use of the information they transmit and receive. In addition, the method for transmitting and receiving signals of the NB-IoT described by FIG. 24 may be performed by a wireless communication device.

The NB-IoT terminal that is turned on again when the power is turned off or newly enters the cell may perform an initial cell search operation such as synchronizing with the base station (S2401). To this end, the NB-IoT terminal may receive NPSS and NSSS from the base station to perform synchronization with the base station (synchronizatoin), and obtain information such as cell identity (cell identity). In addition, the NB-IoT terminal may obtain NPBCH from the base station and obtain intra-cell broadcasting information. In addition, the NB-IoT terminal may receive a DL RS (Downlink Reference Signal) in an initial cell search step and check a downlink channel state.

In other words, if an NB-IoT terminal newly entering a cell exists, the base station may perform an initial cell search operation such as synchronizing with the corresponding terminal. The base station may transmit NPSS and NSSS to the NB-IoT terminal to perform synchronization with the corresponding terminal, and transmit information such as cell identity (cell ID). Also, the base station may transmit (or broadcast) NPBCH to the NB-IoT terminal to transmit intra-cell broadcast information. In addition, the base station may check the downlink channel status by transmitting DL RS in the initial cell search step to the NB-IoT terminal.

After completing the initial cell search, the NB-IoT terminal can obtain more specific system information by receiving the NPDCCH and the corresponding NPDSCH (S2402). In other words, the base station may transmit more detailed system information by transmitting the NPDCCH and the corresponding NPDSCH to the NB-IoT terminal that has completed the initial cell search.

Thereafter, the NB-IoT terminal may perform a random access procedure to complete the access to the base station (S2403 to S2406).

Specifically, the NB-IoT terminal may transmit a preamble to the base station through NPRACH (S2403), and as described above, the NPRACH may be set to be repeatedly transmitted based on frequency hopping or the like to improve coverage. In other words, the base station can (preferably) receive the preamble through the NPRACH from the NB-IoT terminal.

Thereafter, the NB-IoT terminal may receive a random access response (RAR) for the preamble from the base station through the NPDCCH and the corresponding NPDSCH (S2404). In other words, the base station may transmit a random access response (RAR) for the preamble to the NB-IoT terminal through the NPDCCH and the corresponding NPDSCH.

Thereafter, the NB-IoT terminal may transmit the NPUSCH to the base station using scheduling information in the RAR (S2405), and perform a contention resolution procedure such as NPDCCH and the corresponding NPDSCH (S2406). In other words, the base station may receive the NPUSCH from the terminal using the scheduling information in the NB-IoT RAR, and perform the collision resolution procedure.

The NB-IoT terminal performing the above-described procedure can perform NPDCCH / NPDSCH reception (S2407) and NPUSCH transmission (S2408) as a general uplink / downlink signal transmission procedure. In other words, after performing the above-described procedures, the base station may perform NPDCCH / NPDSCH transmission and NPUSCH reception as a general signal transmission / reception procedure to the NB-IoT terminal.

In the case of NB-IoT, as described above, NPBCH, NPDCCH, NPDSCH, etc. can be repeatedly transmitted to improve coverage. In addition, in the case of NB-IoT, UL-SCH (ie, general uplink data) and uplink control information may be transmitted through NPUSCH. At this time, UL-SCH and uplink control information may be set to be transmitted through different NPUSCH formats (eg, NPUSCH format 1, NPUSCH format 2, etc.).

In addition, the control information transmitted by the terminal to the base station may be referred to as UCI (Uplink Control Information). The UCI may include HARQ ACK / NACK (Hybrid Automatic Repeat and reQuest Acknowledgement / Negative-ACK), SR (Scheduling Request), CSI (Channel State Information), and the like. CSI includes Channel Quality Indicator (CQI), Precoding Matrix Indicator (PMI), and Rank Indication (RI). As described above, in NB-IoT, UCI may be generally transmitted through NPUSCH. In addition, according to a request / instruction of a network (eg, a base station), the UE may transmit UCI through a NPUSCH in a periodic (perdiodic), aperiodic, or semi-persistent manner.

Initial Access Procedure of NB-IoT

In the general signal transmission / reception procedure part of the NB-IoT, a procedure in which the NB-IoT terminal initially accesses the base station is briefly described. Specifically, the procedure for the NB-IoT terminal to initially access the base station may include a procedure for searching an initial cell and a procedure for the NB-IoT terminal to acquire system information.

In this regard, a specific signaling procedure between a UE (UE) and a base station (eg, NodeB, eNodeB, eNB, gNB, etc.) associated with the initial connection of the NB-IoT may be illustrated as in FIG. 15. Hereinafter, through the description of FIG. 25, specific details of the initial access procedure of the general NB-IoT, configuration of NPSS / NSSS, and acquisition of system information (eg, MIB, SIB, etc.) will be described.

25 is an example of the initial access procedure of the NB-IoT, and names of physical channels and / or physical signals may be set or referred to differently according to a wireless communication system to which the NB-IoT is applied. As an example, basically, FIG. 25 is described in consideration of the NB-IoT based on the LTE system, but this is only for convenience of description, and the contents thereof can be extendedly applied to the NB-IoT based on the NR system, of course. .

As shown in FIG. 25, the NB-IoT is based on the following signals transmitted on the downlink: primary and secondary narrowband synchronization signals (NPSS and NSSS). NPSS is transmitted through 11 sub-carriers from the first sub-carrier to the 11th sub-carrier in the 6th sub-frame of each frame (S2510), and the NSSS is the first of every even frame for TDD in the 10th sub-frame for FDD. In the second sub-frame, it is transmitted through 12 sub-carriers on the NB-IoT carrier (S2520).

The NB-IoT UE may receive MIB-NB (MasterInformationBlock-NB) on the NPBCH (NB Physical Broadcast Channel) (S130).

MIB-NB uses a fixed schedule with periods of 640 ms and repetitions made within 640 ms. The first transmission of MIB-NB is scheduled in subframe # 0 of radio frames with SFN mod 64 = 0, and repetitions in subframe # 0 of all other radio frames. These transmissions are arranged in eight independently decodable blocks of 80 ms duration.

Thereafter, the NB-IoT UE may receive SIB1-NB (SystemInformationBlockType1-NB) on the PDSCH (S2540).

SIB1-NB uses a fixed schedule with a period of 2560 ms. SIB1-NB transmission occurs in subframe # 4 of another frame in all 16 consecutive frames. The start frame for the first transmission of SIB1-NB is derived by the cell PCID and the number of iterations in the 2560 ms period. Iterations are made at equal intervals within a 2560ms period. The TBS for SystemInformationBlockType1-NB and the repetition made within 2560ms is indicated by the scheduleInfoSIB1 field of MIB-NB.

The SI message is transmitted in time domain windows (referred to as SI-windows) that occur periodically using the scheduling information provided by SystemInformationBlockType1-NB. Each SI message is associated with an SI window, and SI windows of other SI messages do not overlap. That is, only SI corresponding to one SI window is transmitted. If set, the length of the SI window is common to all SI messages.

Within the SI window, the corresponding SI message can be transmitted multiple times through two or eight consecutive NB-IoT downlink subframes depending on the TBS. The UE uses detailed time / frequency domain scheduling information and other information. The other information may be, for example, a transmission format for an SI message in the schedulingInfoList field of SystemInformationBlockType1-NB. The UE does not need to accumulate several SI messages in parallel, but may need to accumulate SI messages across multiple SI windows depending on the coverage condition.

SystemInformationBlockType1-NB sets the length and transmission period of the SI window for all SI messages.

Further, the NB-IoT UE may receive SIB2-NB (SystemInformationBlockType2-NB) on the PDSCH for additional information (S2550).

On the other hand, as shown in Figure 25, NRS means a narrowband reference signal.

NB-IoT random access procedure

In the general signal transmission / reception procedure part of the NB-IoT, a procedure in which the NB-IoT terminal randomly accesses the base station has been briefly described. Specifically, a procedure in which the NB-IoT terminal randomly accesses the base station may be performed through a procedure in which the NB-IoT terminal transmits a preamble to the base station and receives a response thereto.

In this regard, a specific signaling procedure between a UE (UE and a base station (eg, NodeB, eNodeB, eNB, gNB, etc.)) associated with random access of the NB-IoT may be illustrated as in FIG. 26. Hereinafter, description of FIG. 26 Details of random access procedure based on messages (eg, msg1, msg2, msg3, msg4) used in the random access procedure of the general NB-IoT are described through.

26 is an example of a random access procedure of the NB-IoT, and names of each physical channel, physical signal, and / or message may be set or referred to differently according to a wireless communication system to which the NB-IoT is applied. As an example, basically, FIG. 16 is described in consideration of the NB-IoT based on the LTE system, but this is only for convenience of description, and the contents thereof can be extendedly applied to the NB-IoT based on the NR system. .

As shown in FIG. 26, in the case of NB-IoT, the RACH procedure has the same message flow as LTE with different parameters.

Hereinafter, the NPRACH transmitted by the NB-IoT terminal to the base station will be described in detail with respect to the random access procedure of the NB-IoT.

The physical layer random access preamble is based on a single subcarrier frequency hopping symbol group.

27 shows the structure of a group of random access symbols.

As shown in Fig. 27, a group of random access symbols is composed of a sequence of identical symbols having a cyclic prefix of length and a total length. The total number of symbol groups in the preamble repeat unit is denoted by P. The number of time-continuous symbol groups is given by G.

Hereinafter, the techniques / methods proposed in this document are only classified for convenience of description, and it is needless to say that some components of one technique / method may be replaced with other techniques / methods or may be applied in combination with each other.

When an NB-IoT system is designed for an LTE system, a channel raster offset may be generated between an anchor PRB and a channel raster. In addition, the channel raster offset may be set to {+2.5 kHz, -2.5 kHz, +7.5 kHz, -7.5 kHz} values, and information about the channel raster offset is Master Information Block (MIB) of the NPBCH-Narrowband (NB). Can be passed through. Here, the channel raster indicates a minimum unit for reading a downlink synchronization signal when a terminal (eg, UE) performs an initial access procedure or the like.

In the following description, a cell operating in a licensed band (hereinafter, L-band) is defined as an L-cell, and a carrier of the L-cell is defined as (DL / UL) LCC. In addition, a cell operating in an unlicensed band (hereinafter, U-band) is defined as a U-cell, and a carrier of the U-cell is defined as (DL / UL) UCC. The carrier / carrier-frequency of the cell may mean the operating frequency (eg, center frequency) of the cell. The cell / carrier (eg, CC) is collectively referred to as a cell.

28 (a), when a terminal and a base station transmit and receive signals through carrier-coupled LCC and UCC, LCC may be set to PCC (Primary CC) and UCC to SCC (Secondary CC).

As shown in FIG. 28 (b), the terminal and the base station may transmit and receive signals through a single UCC or a plurality of carrier-coupled UCCs. That is, the terminal and the base station can transmit and receive signals through only UCC (s) without LCC.

Hereinafter, the signal transmission / reception operation in the unlicensed band described in the present invention may be performed based on all the above-described deployment scenarios (unless otherwise stated).

Radio frame structure for unlicensed band

For operation in the unlicensed band, LTE frame type 3 or NR frame structure may be used. The configuration of OFDM symbols occupied for uplink / downlink signal transmission in a frame structure for an unlicensed band may be set by a base station. Here, the OFDM symbol may be replaced with an SC-FDM (A) symbol.

For downlink signal transmission through the unlicensed band, the base station may inform the UE of the configuration of OFDM symbols used in subframe #n through signaling.

Here, the subframe may be replaced with a slot or a time unit (TU).

Specifically, in the case of an LTE system supporting an unlicensed band, the UE subframe # n-1 or subframe #n through a specific field in the DCI received from the base station (eg, Subframe configuration for LAA field, etc.) It is possible to assume (or identify) the configuration of the OFDM symbols occupied in n.

Table 15 shows the configuration of OFDM symbols in which a subframe configuration for LAA field in the LTE system is used for transmission of a downlink physical channel and / or physical signal in a current subframe and / or a next subframe. Illustrate the method shown.

Table 15

In order to transmit an uplink signal through an unlicensed band, the base station may inform the UE of information on the uplink transmission interval through signaling.

Specifically, in the case of an LTE system supporting an unlicensed band, the terminal may acquire 'UL duration' and 'UL offset' information for the subframe #n through the 'UL duration and offset' field in the detected DCI.

Table 16 illustrates a method in which the UL duration and offset field in the LTE system indicates UL offset and UL duration configuration.

Table 16

As an example, when the UL duration and offset field sets (or indicates) UL offset l and UL duration d for subframe #n, the UE subframe # n + l + i (i = 0,1,…, There is no need to receive downlink physical channels and / or physical signals within d-1).

Downlink signal transmission method through unlicensed band

The base station may perform one of the following unlicensed band access procedures (eg, Channel Access Procedure, CAP) for downlink signal transmission in the unlicensed band.

(1) First downlink CAP method

The base station may initiate a channel access process (CAP) for downlink signal transmission over an unlicensed band (eg, signal transmission including PDSCH / PDCCH / EPDCCH) (S1910). The base station may arbitrarily select the backoff counter N within the contention window CW according to step 1. At this time, the N value is set to the initial value Ninit (S1920). Ninit is selected as a random value between 0 and CWp. Subsequently, if the backoff counter value N is 0 according to step 4 (S1930; Y), the base station ends the CAP process (S1932). Subsequently, the base station may perform Tx burst transmission including PDSCH / PDCCH / EPDCCH (S1934). On the other hand, if the backoff counter value is not 0 (S1930; N), the base station decreases the backoff counter value by 1 according to step 2 (S1940). Subsequently, the base station checks whether the channel of the U-cell (s) is idle (S1950), and if the channel is idle (S1950; Y), checks whether the backoff counter value is 0 (S1930). On the contrary, if the channel is not idle in step S1950, that is, if the channel is busy (S1950; N), the base station performs a delay period (defer duration Td; 25usec or more) longer than the slot time (eg, 9usec) according to step 5 It is checked whether the corresponding channel is idle (S1960). If the channel is idle in the delay period (S1970; Y), the base station can resume the CAP process again. Here, the delay period may be composed of 16usec periods and immediately following mp consecutive slot times (eg, 9usec). On the other hand, if the channel is busy during the delay period (S1970; N), the base station performs the step S1960 again to check whether the channel of the U-cell (s) is idle during the new delay period.

Table 17 exemplifies that mp, minimum CW, maximum CW, maximum channel occupancy time (MCOT), and allowed CW sizes applied to the CAP vary according to the channel access priority class.

Table 17

The contention window size applied to the first downlink CAP may be determined based on various methods. For example, the contention window size may be adjusted based on a probability that HARQ-ACK values corresponding to PDSCH transmission (s) in a certain time period (eg, a reference TU) are determined as NACK. When the base station performs downlink signal transmission including the PDSCH associated with the channel access priority class p on the carrier, HARQ-ACK values corresponding to PDSCH transmission (s) in the reference subframe k (or reference slot k) are NACK. When the probability to be determined is at least Z = 80%, the base station increases the set CW values for each priority class to the next allowed next priority. Or, the base station maintains the CW values set for each priority class as initial values. The reference subframe (or reference slot) may be defined as a start subframe (or start slot) in which at least some HARQ-ACK feedback is available on which a most recent signal transmission on a corresponding carrier is performed.

(2) 2nd downlink CAP method

The base station may perform a downlink signal transmission through an unlicensed band (eg, a signal transmission including discovery signal transmission and no PDSCH) based on the second downlink CAP method described below.

When the length of the signal transmission section of the base station is 1 ms or less, the base station transmits a downlink signal (eg, discovery signal transmission) through an unlicensed band immediately after the corresponding channel is sensed as idle for at least a sensing period Tdrs = 25 us. And PDSCH). Here, Tdrs is composed of one slot section Tsl = 9us, followed by section Tf (= 16us).

(3) 3rd downlink CAP method

The base station can perform the following CAP for downlink signal transmission through multiple carriers in an unlicensed band.

1) Type A: The base station performs CAP on multiple carriers based on counter N (counter N considered in CAP) defined for each carrier, and performs downlink signal transmission based on this.

-Type A1: Counter N for each carrier is determined independently of each other, and downlink signal transmission through each carrier is performed based on the counter N for each carrier.

-Type A2: Counter N for each carrier is determined as an N value for the carrier having the largest contention window size, and downlink signal transmission through the carrier is performed based on the counter N for each carrier.

2) Type B: The base station performs a CAP based on the counter N only for a specific carrier among a plurality of carriers, and performs downlink signal transmission by determining whether or not to channel idle for the remaining carriers prior to signal transmission on the specific carrier .

-Type B1: A single contention window size is defined for a plurality of carriers, and the base station utilizes a single contention window size when performing CAP based on Counter N for a specific carrier.

-Type B2: The contention window size is defined for each carrier, and when determining the Ninit value for a specific carrier, the largest contention window size among the contention window sizes is used.

Method of transmitting uplink signal through unlicensed band

The UE performs contention-based CAP for transmission of an uplink signal in an unlicensed band. The UE performs Type 1 or Type 2 CAP for uplink signal transmission in the unlicensed band. In general, the terminal may perform a CAP (eg, Type 1 or Type 2) set by the base station for the transmission of the uplink signal.

(1) Type 1 uplink CAP method

The terminal may initiate a channel access process (CAP) for signal transmission through the unlicensed band (S2010). The terminal may arbitrarily select the backoff counter N in the contention window CW according to step 1. At this time, the N value is set to the initial value Ninit (S2020). Ninit is selected from any value between 0 and CWp. Subsequently, if the backoff counter value N is 0 according to step 4 (S2030; Y), the terminal ends the CAP process (S2032). Subsequently, the UE may perform Tx burst transmission (S2034). On the other hand, if the backoff counter value is not 0 (S2030; N), the terminal decreases the backoff counter value by 1 according to step 2 (S2040). Subsequently, the UE checks whether the channel of the U-cell (s) is idle (S2050), and if the channel is idle (S2050; Y), checks whether the backoff counter value is 0 (S2030). Conversely, if the channel is not idle in step S2050, that is, when the channel is busy (S2050; N), the UE performs a delay period (defer duration Td; 25usec or more) longer than the slot time (eg, 9usec) according to step 5 It is checked whether the corresponding channel is idle (S2060). If the channel is idle in the delay period (S2070; Y), the UE may resume the CAP process again. Here, the delay period may be composed of 16usec periods and immediately following mp consecutive slot times (eg, 9usec). On the other hand, if the channel is busy during the delay period (S2070; N), the UE performs step S2060 again to check whether the channel is idle during the new delay period.

Table 18 exemplifies that mp, minimum CW, maximum CW, maximum channel occupancy time (MCOT), and allowed CW sizes applied to the CAP vary according to the channel access priority class.

Table 18

The contention window size applied to the Type 1 uplink CAP may be determined based on various methods. For example, the contention window size may be adjusted based on whether to toggle the New Data Indicator (NDI) value for at least one HARQ processor associated with HARQ_ID_ref, which is the HARQ process ID of the UL-SCH in a certain time interval (eg, reference TU). have. When the UE performs signal transmission using the Type 1 channel access procedure related to the channel access priority class p on the carrier, the UE receives all priority classes when the NDI value for at least one HARQ process associated with HARQ_ID_ref is toggled.

for,

Set to, if not, all priority classes

CWp for increases to the next higher allowed value.

The reference subframe nref (or reference slot nref) is determined as follows.

The UE receives the UL grant in the subframe (or slot) ng and the subframe (or slot)

In the case of performing transmission including a UL-SCH without a gap starting from a subframe (or slot) n0 within (here, the subframe (or slot) nw is the terminal transmits the UL-SCH based on the Type 1 CAP The subframe (or slot) is the most recent subframe (or slot) before ng-3), and the reference subframe (or slot) nref is subframe (or slot) n0.

(2) Type 2 uplink CAP method

When a UE uses a Type 2 CAP for transmission of an uplink signal (eg, a signal including PUSCH) through an unlicensed band, the UE at least senses a section

Meanwhile, an uplink signal (eg, a signal including PUSCH) may be transmitted through an unlicensed band immediately after sensing that the channel is idle. Tshort_ul is one slot interval

Immediately following (immediately followed)

It consists of. Tf includes an idle slot section Tsl at the starting point of the Tf.

C. Structure of uplink and downlink channels

Downlink channel structure

The base station transmits a related signal to a terminal through a downlink channel described later, and the terminal receives a related signal from a base station through a downlink channel described later.

(1) Physical downlink shared channel (PDSCH)

PDSCH carries downlink data (eg, DL-shared channel transport block, DL-SCH TB), and modulation methods such as Quadrature Phase Shift Keying (QPSK), 16 Quadrature Amplitude Modulation (QAMK), 64 QAM, and 256 QAM are used. Applies. A codeword is generated by encoding TB. PDSCH can carry up to two codewords. For each codeword, scrambling and modulation mapping are performed, and modulation symbols generated from each codeword are mapped to one or more layers (Layer mapping). Each layer is mapped to a resource together with a DMRS (Demodulation Reference Signal) and is generated as an OFDM symbol signal and transmitted through a corresponding antenna port.

(2) Physical downlink control channel (PDCCH)

The PDCCH carries downlink control information (DCI) and a QPSK modulation method is applied. One PDCCH is composed of 1, 2, 4, 8, and 16 control channel elements (CCEs) according to an aggregation level (AL). One CCE is composed of six Resource Element Groups (REGs). One REG is defined by one OFDM symbol and one (P) RB.

31 illustrates one REG structure.

In FIG. 31, D denotes a resource element (RE) to which DCI is mapped, and R denotes RE to which DMRS is mapped. DMRS is mapped to the 1st, 5th, and 9th REs in the frequency domain direction within one symbol.

The PDCCH is transmitted through a control resource set (CORESET). CORESET is defined as a set of REGs with a given pneumonology (eg, SCS, CP length, etc.). Multiple OCRESETs for one UE may overlap in the time / frequency domain. CORESET may be set through system information (eg, MIB) or UE-specific higher layer (eg, Radio Resource Control, RRC, layer) signaling. Specifically, the number of RBs and the number of symbols (up to 3) constituting the CORESET may be set by higher layer signaling.

The precoder granularity in the frequency domain for each CORESET is set to one of the following by higher layer signaling:

-sameAsREG-bundle: same as REG bundle size in frequency domain

-allContiguousRBs: equal to the number of consecutive RBs in the frequency domain inside CORESET

REGs in CORESET are numbered based on a time-first mapping manner. That is, REGs are sequentially numbered from 0 starting from the first OFDM symbol in the lowest-numbered resource block inside CORESET.

The CCE to REG mapping type is set to one of a non-interleaved CCE-REG mapping type or an interleaved CCE-REG mapping type.

32 illustrates a non-interleaved CCE-REG mapping type.

As shown in Figure 32, non-interleaved (non-interleaved) CCE-REG mapping type (or localized mapping type): 6 REGs for a given CCE constitute one REG bundle, and all REGs for a given CCE Continuity. One REG bundle may correspond to one CCE.

33 illustrates an interleaved CCE-REG mapping type.

33, interleaved CCE-REG mapping type (or distributed mapping type): 2, 3, or 6 REGs for a given CCE constitute one REG bundle, and the REG bundle is within CORESET. Interleaved. The REG bundle in CORESET composed of 1 OFDM symbol or 2 OFDM symbols consists of 2 or 6 REGs, and the REG bundle in CORESET composed of 3 OFDM symbols consists of 3 or 6 REGs. The size of the REG bundle can be set for each CORESET.

Figure 34 illustrates a block interleaver.

The number of rows (A) of the (block) interleaver for the interleaving operation as described above is set to one of 2, 3 and 6. When the number of interleaving units for a given CORESET is P, the number of columns of the block interleaver is equal to P / A. The write operation for the block interleaver is performed in the row-first direction as shown in FIG. 34 below, and the read operation is performed in the column-first direction. The cyclic shift (CS) of the interleaving unit is applied based on an ID that can be set independently for an ID that can be set for DMRS.

The UE performs decoding (aka blind decoding) on a set of PDCCH candidates to obtain DCI transmitted through the PDCCH. The set of PDCCH candidates that the UE decodes is defined as a set of PDCCH search spaces. The search space set may be a common search space or a UE-specific search space. The UE may obtain DCI by monitoring PDCCH candidates in one or more set of search spaces set by MIB or higher layer signaling. Each CORESET setting is associated with one or more search space sets, and each search space set is associated with one COREST setting. One set of search spaces is determined based on the following parameters.

-controlResourceSetId: represents a set of control resources related to the search space set

-monitoringSlotPeriodicityAndOffset: Indicates PDCCH monitoring interval (slot unit) and PDCCH monitoring interval offset (slot unit)

-monitoringSymbolsWithinSlot: indicates the PDCCH monitoring pattern in the slot for PDCCH monitoring (eg, indicates the first symbol (s) of the control resource set)

-nrofCandidates: Indicates the number of PDCCH candidates (one of 0, 1, 2, 3, 4, 5, 6, 8) by AL = {1, 2, 4, 8, 16}

Table 19 illustrates features for each type of search space.

Table 19

Table 20 illustrates DCI formats transmitted on the PDCCH.

Table 20

DCI format 0_0 is used to schedule TB-based (or TB-level) PUSCH, DCI format 0_1 is TB-based (or TB-level) PUSCH or CBG (Code Block Group) -based (or CBG-level) PUSCH It can be used to schedule. DCI format 1_0 is used to schedule the TB-based (or TB-level) PDSCH, DCI format 1_1 is used to schedule the TB-based (or TB-level) PDSCH or CBG-based (or CBG-level) PDSCH Can be. DCI format 2_0 is used to deliver dynamic slot format information (eg, dynamic SFI) to the terminal, and DCI format 2_1 is used to deliver downlink pre-Emption information to the terminal. DCI format 2_0 and / or DCI format 2_1 may be delivered to UEs in a corresponding group through a group common PDCCH (PDCCH), which is a PDCCH delivered to UEs defined as one group.

Uplink channel structure

The terminal transmits the related signal to the base station through the uplink channel described later, and the base station receives the related signal from the terminal through the uplink channel described later.

(1) Physical uplink shared channel (PUSCH)

PUSCH carries uplink data (eg, UL-shared channel transport block, UL-SCH TB) and / or uplink control information (UCI), and CP-OFDM (Cyclic Prefix-Orthogonal Frequency Division Multiplexing) waveform Or, it is transmitted based on a DFT-s-OFDM (Discrete Fourier Transform-spread-Orthogonal Frequency Division Multiplexing) waveform. When the PUSCH is transmitted based on the DFT-s-OFDM waveform, the UE transmits the PUSCH by applying transform precoding. For example, if transform precoding is not possible (eg, transform precoding is disabled), the UE transmits a PUSCH based on the CP-OFDM waveform, and if transform precoding is possible (eg, transform precoding is enabled), the UE is CP-OFDM. PUSCH may be transmitted based on a waveform or a DFT-s-OFDM waveform. PUSCH transmission is dynamically scheduled by UL grant in DCI, or semi-static based on upper layer (eg, RRC) signaling (and / or Layer 1 (L1) signaling (eg, PDCCH)). Can be scheduled (configured grant). PUSCH transmission may be performed on a codebook basis or a non-codebook basis.

(2) Physical uplink control channel (PUCCH)

PUCCH carries uplink control information, HARQ-ACK and / or scheduling request (SR), and is divided into Short PUCCH and Long PUCCH according to the PUCCH transmission length. Table 21 illustrates PUCCH formats.

Table 21

PUCCH format 0 carries UCI up to 2 bits in size, and is mapped and transmitted based on a sequence. Specifically, the UE transmits one sequence among a plurality of sequences through PUCCH in PUCCH format 0 to transmit a specific UCI to the base station. The UE transmits a PUCCH in PUCCH format 0 in PUCCH resource for setting a corresponding SR only when transmitting a positive SR.

PUCCH format 1 carries UCI up to 2 bits in size, and modulation symbols are spread in an orthogonal cover code (OCC) in the time domain (set differently depending on whether frequency hopping is performed). DMRS is transmitted on a symbol in which a modulation symbol is not transmitted (ie, time division multiplexing (TDM)).

PUCCH format 2 carries UCI having a bit size larger than 2 bits, and modulation symbols are transmitted through DMRS and Frequency Division Multiplexing (FDM). DM-RS is located at symbol indices # 1, # 4, # 7, and # 10 in a given resource block at a density of 1/3. PN (Pseudo Noise) sequence is used for the DM_RS sequence. For 2 symbol PUCCH format 2, frequency hopping may be activated.

PUCCH format 3 does not allow terminal multiplexing in the same physical resource blocks, and carries a UCI having a bit size larger than 2 bits. In other words, PUCCH resources of PUCCH format 3 do not include orthogonal cover codes. The modulation symbol is transmitted by DMRS and Time Division Multiplexing (TDM).

PUCCH format 4 supports multiplexing up to 4 UEs in the same physical resource block, and carries a UCI having a bit size larger than 2 bits. In other words, PUCCH resource of PUCCH format 3 includes an orthogonal cover code. The modulation symbol is transmitted by DMRS and Time Division Multiplexing (TDM).

Semi-Persistent Scheduling (SPS)

Semi-Persistent Scheduling (SPS) is a scheduling method for allocating resources to be maintained continuously for a specific period of time.

When a certain amount of data is transmitted for a certain period of time, such as VoIP (Voice over Internet Protocol), it is not necessary to transmit control information for every data transmission section for resource allocation. . In the so-called SPS method, a time resource region in which resources can be allocated to a terminal is first allocated.

In this case, in the semi-persistent allocation method, a time resource region allocated to a specific terminal may be set to have periodicity. Then, allocation of time-frequency resources is completed by allocating frequency resource regions as necessary. The allocation of the frequency resource region in this way may be referred to as so-called activation. If the semi-persistent allocation method is used, since resource allocation is maintained for a certain period of time by one signaling, it is not necessary to repeatedly allocate resources, thereby reducing signaling overhead.

Thereafter, when there is no need for resource allocation for the terminal, signaling for releasing frequency resource allocation may be transmitted from the base station to the terminal. Release of the allocation of the frequency resource region in this way may be referred to as deactivation.

Currently, in LTE, SPS for uplink and / or downlink is firstly informed to the UE of which subframes SPS transmission / reception should be via radio resource control (RRC) signaling. That is, a time resource is first designated among time-frequency resources allocated for SPS through RRC signaling. In order to indicate a subframe that can be used, for example, a period and an offset of the subframe may be reported. However, since the UE is allocated only a time resource region through RRC signaling, transmission and reception by the SPS is not immediately performed even if RRC signaling is received, and allocation of the time-frequency resource is completed by allocating a frequency resource region as necessary. . The allocation of the frequency resource region may be referred to as activation, and the release of the allocation of the frequency resource region may be referred to as deactivation.

Therefore, after receiving the PDCCH indicating the activation, the UE allocates frequency resources according to RB allocation information included in the received PDCCH and modulates and code rates according to Modulation and Coding Scheme (MCS) information. Rate), and starts transmitting / receiving according to the subframe period and offset allocated through the RRC signaling.

Then, when the UE receives the PDCCH indicating the deactivation from the base station, it stops transmission and reception. If a PDCCH indicating activation or re-activation is received after stopping transmission / reception, transmission / reception is resumed with a subframe period and offset allocated by RRC signaling using RB allocation and MCS specified in the PDCCH. That is, the allocation of the time resource is performed through RRC signaling, but the transmission and reception of the actual signal can be performed after receiving the PDCCH indicating activation and reactivation of the SPS, and the suspension of the transmission and reception of the signal indicates the deactivation of the SPS PDCCH. It is done after receiving.

Specifically, when the SPS is activated by the RRC, the following information may be provided.

-SPS C-RNTI

-If SPS for uplink is activated, the number of empty transmissions before the uplink SPS interval (semiPersistSchedIntervalUL) and implicit termination

-In the case of TDD, whether twoIntervalsConfig is enabled or disabled for uplink

-When SPS for downlink is activated, the number of HARQ processes configured for downlink SPS interval (semiPersistSchedIntervalDL) and SPS

Alternatively, if the SPS is deactivated by the RRC, the set grant or set assignment must be discarded.

In addition, SPS is supported only in SpCell, and is not supported for RN communication with E-UTRAN with RN subframe configuration.

With respect to the downlink SPS, after the semi-persistent downlink assignment is set, the MAC entity needs to sequentially consider that the Nth designation occurs in a subframe, as shown in Equation 3 below. There is.

[Equation 3]

In Equation 3, SFNstart time and subframestart time mean SFN and subframe in which the set downlink designation is (re) initialized, respectively. In the case of BL UEs or UEs with improved coverage, SFNstart time and subframestart time may refer to the SFN and subframe of the first PDSCH transmission in which the set downlink designation is (re) initialized.

On the contrary, with respect to the uplink SPS, after the SPS uplink grant (Semi-Persistent Scheduling uplink grant) is set, the MAC entity sequentially generates an N-th grant in a subframe, as shown in Equation 4 below. It needs to be considered.

[Equation 4]

In Equation 4, SFNstart time and subframestart time mean SFN and subframe in which the set uplink grant is (re) initialized, respectively. In the case of BL UEs or UEs with improved coverage, the SFNstart time and subframestart time may refer to the SFN and subframe of the first PDSCH transmission that is initialized (re) initialized.

Table 22 below is an example of an RRC message (SPS-Config) for specifying the above-described SPS setting.

Table 22

PDCCH / EPDCCH / MPDCCH validation for semi-persistent scheduling

The terminal may check the PDCCH including the SPS indication when all of the following conditions are satisfied. First, the CRC parity bit added for the PDCCH payload should be scrambled with SPS C-RNTI, and second, the New Data Indicator (NDI) field should be set to 0. Here, in the case of DCI formats 2, 2A, 2B, 2C, and 2D, the new data indicator field indicates one of the activated transport blocks.

In addition, the UE can check the EPDCCH including the SPS indication when all of the following conditions are satisfied. First, the CRC parity bit added for the EPDCCH payload should be scrambled with SPS C-RNTI, and second, the new data indicator (NDI) field should be set to 0. Here, in the case of DCI formats 2, 2A, 2B, 2C, and 2D, the new data indicator field indicates one of the activated transport blocks.

In addition, the UE may check the MPDCCH including the SPS indication when all of the following conditions are satisfied. First, the CRC parity bit added for the MPDCCH payload should be scrambled with SPS C-RNTI, and second, the new data indicator (NDI) field should be set to 0.

When each field used in the DCI format is set according to Table 23 or Table 24, Table 25, and Table 26 below, verification is completed. When the verification is completed, the UE recognizes the received DCI information as valid SPS activation or deactivation (or release). On the other hand, if the verification is not completed, the UE recognizes that the received DCI format includes a non-matching CRC.

Table 23 shows a field for PDCCH / EPDCCH identification indicating SPS activation.

Table 23

Table 24 shows a field for PDCCH / EPDCCH confirmation indicating SPS deactivation (or release).

Table 24

Table 25 shows fields for MPDCCH identification indicating SPS activation.

Table 25

Table 26 shows a field for MPDCCH confirmation indicating SPS deactivation (or release).

Table 26

When the DCI format indicates SPS downlink scheduling activation, the TPC command value for the PUCCH field may be used as an index indicating four PUCCH resource values set by the upper layer.

Table 27 shows PUCCH resource values for downlink SPS.

Table 27

Downlink control channel related procedure in NB-IoT

Let's take a look at the procedure related to Narrowband Physical Downlink Control Channel (NPDCCH) used in NB-IoT.

The UE needs to monitor NPDCCH candidates (that is, a set of NPDCCH candidates) as set by upper layer signaling for control information. Here, the monitoring may mean attempting to decode each NPDCCH in the set according to all DCI formats to be monitored. The set of NPDCCH candidates for monitoring may be defined as an NPDCCH search space. In this case, the UE may perform monitoring using an identifier (eg, C-RNTI, P-RNTI, SC-RNTI, G-RNTI) corresponding to the corresponding NPDCCH search area.

In this case, the terminal a) Type1-NPDCCH common search area (Type1-NPDCCH common search space), b) Type2-NPDCCH common search area (Type2-NPDCCH common search space), and c) NPDCCH terminal-specific search area (NPDCCH UE-specific search space). At this time, the UE does not need to simultaneously monitor the NPDCCH UE-specific discovery region and the Type1-NPDCCH common discovery region. In addition, the terminal does not need to simultaneously monitor the NPDCCH terminal-specific search area and the Type2-NPDCCH common search area. In addition, the terminal does not need to simultaneously monitor the Type1-NPDCCH common search area and the Type2-NPDCCH common search area.

The NPDCCH search region at the aggregation level and repetition level is defined by a set of NPDCCH candidates. Here, each NPDCCH candidate is repeated in R consecutive NB-IoT downlink subframes except for the subframe used for transmission of the SI (System Information) message starting from subframe k.

In the case of the NPDCCH terminal-specific search area, aggregation and repetition levels defining the search area and corresponding monitored NPDCCH candidates are replaced by substituting RMAX values with the parameter al-Repetition-USS set by the upper layer (Table 28). Is listed as

Table 28

In the case of the Type1-NPDCCH common search region, the aggregation and repetition levels that define the search region and the corresponding monitored NPDCCH candidates are replaced with the parameters set by the upper layer, al-Repetition-CSS-Paging, as shown in Table 29 and Table 29. Are listed together.

Table 29

In the case of the Type2-NPDCCH common search area, the aggregation and repetition levels defining the search area and the corresponding monitored NPDCCH candidates are listed as shown in Table 30 as the RMAX value is replaced with the parameter npdcch-MaxNumRepetitions-RA set by the upper layer. do.

Table 30

At this time, the position of the starting subframe k is given by k = kb. Here, kb refers to the b-th consecutive NB-IoT downlink subframe from subframe k0, the b is u * R, and the u is 0, 1, .. (RMAX / R) -1 do. In addition, the subframe k0 means a subframe satisfying Equation (5).

[Equation 5]

In the case of the NPDCCH terminal-specific search area, G shown in Equation 5 is given by the upper layer parameter nPDCCH-startSF-UESS,

Is given by the upper layer parameter nPDCCH-startSFoffset-UESS. In addition, in the case of the NPDCCH Type2-NPDCCH common search region, G shown in Equation 5 is given by the upper layer parameter nPDCCH-startSF-Type2CSS,

Is given by the upper layer parameter nPDCCH-startSFoffset-Type2CSS. In addition, in the case of the Type1-NPDCCH common search region, k is k0 and is determined from the location of the NB-IoT paging opportunity subframe.

When the terminal is set by the upper layer as a PRB for monitoring the NPDCCH terminal-specific light-colored area, the terminal should monitor the NPDCCH terminal-specific search area in the PRB set by the upper layer. In this case, the UE does not expect to receive NPSS, NSSS, and NPBCH in the corresponding PRB. On the other hand, if the PRB is not set by the upper layer, the UE should monitor the NPDCCH UE-specific search area in the same PRB where NPSS / NSSS / NPBCH was detected.

When the NB-IoT UE detects an NPDCCH having DCI format N0 (DCI format N0) ending in subframe n, and when transmission of the corresponding NPUSCH format 1 (NPUSCH format 1) starts in subframe n + k, the UE Does not need to monitor the NPDCCH of any subframe starting within the range from subframe n + 1 to subframe n + k-1.

In addition, when the NB-IoT terminal detects the NPDCCH having DCI format N1 (DCI format N1) or DCI format N2 (DCI format N2) ending in subframe n, and transmission of the corresponding NPDSCH starts in subframe n + k If it does, the UE does not need to monitor the NPDCCH of any subframe starting within the range from subframe n + 1 to subframe n + k-1.

In addition, when the NB-IoT terminal detects the NPDCCH having DCI format N1 ending in subframe n, and when the transmission of the corresponding NPUSCH format 2 starts in subframe n + k, the terminal starts subframe n + 1. It is not necessary to monitor the NPDCCH of any subframe starting within the range up to frame n + k-1.

In addition, when the NB-IoT terminal detects an NPDCCH having DCI format N1 for "PDCCH order" ending in subframe n, and when transmission of the corresponding NPRACH starts in subframe n + k, the terminal Does not need to monitor the NPDCCH of any subframe starting within the range from subframe n + 1 to subframe n + k-1.

In addition, when the NB-IoT terminal has NPUSCH transmission ending in subframe n, the terminal need not monitor the NPDCCH of any subframe starting within the range from subframe n + 1 to subframe n + 3. .

In addition, when the NPDCCH candidate of the NPDCCH search region in subframe n ends, and when the UE is set to monitor the NPDCCH candidate of another NPDCCH search region starting before subframe n + 5, the NB-IoT terminal of the NPDCCH search region There is no need to monitor NPDCCH candidates.

With respect to the NPDCCH starting position, the starting OFDM symbol for the NPDCCH is given by the index lNPDCCHStart, in the first slot of subframe k. At this time, when the upper layer parameter operarionModeInfo indicates '00' or '01', the index lNPDCCHStart is given by the upper layer parameter eutaControlRegionSize. Alternatively, when the higher layer parameter operarionModeInfo indicates '10' or '11', the index lNPDCCHStart is 0.

NPDCCH validation for SPS for semi-persistent scheduling

The UE may determine that the NPDCCH that allocates semi-persistent scheduling is valid only when all of the following conditions are satisfied.

-The CRC parity bit obtained for the NPDCCH payload should be scrambled with Semi-persistent scheduling C-RNTI.

-The new data indicator field (new data indicator) should be set to '0'.

If all fields for the DCI format N0 used are set according to Table 31 or Table 32 below, the validity of the NPDCCH can be confirmed.

Table 31

Table 32

When the validity of the NPDCCH is confirmed, the UE should regard the NPDCCH as valid semi-permanent scheduling activation or release according to received DCI information.

If the validity of the NPDCCH is not confirmed, the UE should consider the received DCI information as received with a CRC that does not match.

Downlink control information format (DCI format)

DCI transmits downlink or uplink scheduling information for one cell and one RNTI. Here, the RNTI is implicitly CRC encoded.

DCI format N0 (DCI format N0), DCI format N1 (DCI format N1), and DCI format N2 (DCI format N2) may be considered as DCI formats related to NB-IoT.

First, DCI format N0 is used for scheduling of NPUSCH in one UL cell, and can transmit the following information.

-Flag for distinguishing between format N0 and format N1 (eg, 1 bit), where the value 0 indicates format N0 and the value 1 can indicate format N1.

-Subcarrier indication (eg 6 bit)

-Resource assignment (eg 3 bits)

-Scheduling delay (eg 2 bits)

-Modulation and Coding Scheme (eg 4 bits)

-Redundancy version (eg 1 bit)

-Repetition number (eg 3 bits)

-New data indicator (eg 1 bit)

-DCI subframe repetition number (DCI subframe repetition number) (eg, 2 bits)

Next, DCI format N1 is used for scheduling of one NPDSCH codeword in one cell and a random access procedure initiated by an NPDCCH order. At this time, DCI corresponding to the NPDCCH order may be carried by the NPDCCH.

The DCI format N1 may transmit the following information.

In the format N1, the NPDCCH order indicator is set to '1', and when the CRC (Cyclic Redundancy Check) of the format N1 is scrambled to C-RNTI, and all other fields are set as follows, the random access procedure initiated by the NPDCCH order It is used for.

-Starting number of NPRACH repetitions (eg 2 bits)

-Subcarrier indication of NPRACH (eg, 6 bits)

-All other bits of format N1 are set to '1'.

Otherwise, the following remaining information is transmitted.

-Scheduling delay (eg 3 bits)

-Resource assignment (eg 3 bits)

-Modulation and Coding Scheme (eg 4 bits)

-Repetition number (eg 4 bits)

-New data indicator (eg 1 bit)

-HARQ-ACK resource (HARQ-ACK resource) (eg, 4 bits)

-DCI subframe repetition number (DCI subframe repetition number) (eg, 2 bits)

When the CRC of format N1 is scrambled with RA-RNTI, the following information (ie, field) among the information (ie, fields) is reserved.

-New data indicator

-HARQ-ACK resource

At this time, if the number of information bits in format N1 is smaller than the number of information bits in format N0, '0' must be attached until the payload size of format N1 is equal to the payload size of format N0.

Next, DCI format N2 is used for paging and direct indication, and may transmit the following information.

-Flag for distinguishing between paging and direct indication (eg, 1 bit), where a value of 0 indicates a direct indication and a value of 1 indicates paging.

When the value of the flag is 0, DCI format N2 is direct indication information (eg, 8 bits) and reserved information bits (reserved for setting the same size as format N2 having a flag value of 1). information bits).

On the other hand, if the value of the flag is 1, DCI format N2 is resource allocation (eg, 3 bits), modulation and coding technique (eg, 4 bits), number of repetitions (eg, 4 bits), DCI subframe repetition times ( Example: 3 bits).

Resource allocation for uplink transmission with configured grant

If the PUSCH resource allocation is semi-persistently set by the upper layer parameter ConfiguredGrantConfig of the bandwidth information element (BWP information element) and the PUSCH transmission corresponding to the configured grant is triggered, the next higher layer Parameters apply to the PUSCH transmission:

-For type 1 PUSCH transmission by configured grant, the following parameters are provided in ConfiguredGrantConfig.

-The upper layer parameter timeDomainAllocation value m provides a row index m + 1 indicating an allocated table, and the allocated table indicates a combination of a start symbol, length and PUSCH mapping type. Here, the table selection follows the rules for the UE specific search space defined in 6.1.2.1.1 of TS38.214.

-Frequency domain resource allocation, for a given resource allocation type indicated by resourceAllocation, is determined by the upper layer parameter frequencyDomainAllocation according to the procedure of Section 6.1.2.2 of TS38.214.

-IMCS is provided by the upper layer parameter mcsAndTBS.

-As in Section 7.3.1.1 of TS 38.212, the number of DM-RS CDM group, DM-RS port, SRS resource indication and DM-RS sequence initialization is determined. Antenna port values, bit values for DM-RS sequence initialization, precoding information and number of layers, and SRS resource indicators are provided by antennaPort, dmrs-SeqInitialization, precodingAndNumberOfLayers, and srs-ResourceIndicator, respectively.

-When frequency hopping is enabled, the frequency offset between two frequency hops may be set by the upper layer parameter frequencyHoppingOffset.

-For type 2 PUSCH transmission by configured grant: resource allocation follows the upper layer setting according to [10, TS 38.321] and the UL grant received from the downlink control information (DCI) .

When a higher level layer does not transmit a transport block to be transmitted from a resource allocated for uplink transmission without grant, the terminal does not transmit anything on the resource set by ConfiguredGrantConfig.

The set of allowed periods P is defined in [12, TS 38.331].

Transport block repetition for uplink transmission with a configured grant

The upper layer configuration parameters repK and repK-RV define K repetition to be applied to the transmitted transport block and RV pattern (Redundancy Version pattern) to be applied to the repetition. For the n-th transmission case among the K repetitions (n = 1, 2, .., K), the transmission is associated with the (mod (n-1,4) +1) th value in the set RV sequence. The initial transmission of the transport block can be started in the following cases.

-When the set RV sequence is {0,2,3,1}, the first transmission occasion of K repetitions (the first transmission occasion)

-If the set RV sequence is {0,3,0,3}, one of transmission opportunities of K repetition related to RV = 0.

-If the set RV sequence is {0,0,0,0}, one of K repeat transmission opportunities (excluding the last transmission opportunity when K = 8)

For an arbitrary RV sequence, repetition is the case of repeatedly transmitting K times, the last transmission opportunity of K times within the period P, or the case where the UL grant for scheduling the same TB is received within the period P It must end at the point of first arrival.

In relation to the time duration for transmission of K repetition, the terminal does not expect that a duration greater than the duration induced by period P will be set.

For both type 1 and type 2 PUSCH transmission, when repK> 1 is set in the terminal, the terminal must repeat the TB through consecutive repK slots by applying the same symbol allocation in each slot. When a UE procedure for determining a slot configuration defined in Section 11.1 of TS 38.213 determines a symbol of a slot allocated for PUSCH as a downlink symbol, transmission in a corresponding slot for multi-slot PUSCH transmission is omitted. .

Uplink power control in NB-IoT

The uplink power control controls transmission power of other uplink physical channels.

UE uplink power control operation (UE Behavior)

UE transmission power for narrowband physical uplink shared channel (NPUSCH) transmission is defined as follows. In the case of FDD, the UE can use enhanced random access power control [12], and is configured by the upper layer, and in the case of TDD, the UE that initiates the random access procedure at the first or second configured NPRACH repetition level is enhanced Random access power control should be applied.

Serving cell

Transmission power of UE for NPUSCH transmission in NB-IoT uplink slot i

Is given as:

When the enhanced random access power control is not applied, for NPUSCH (re) transmission corresponding to random access response grant and all other NPUSCH transmissions in which the number of repetitions of the allocated NPUSCH RU is greater than two:

[Equation 6]

In other cases,

[Equation 7]

here,

-

The cell

The configured UE transmit power as defined in [6] of NB-IoT UL slot i for serving.

-

Is serving cell at j = 1

For components provided from higher layers

, Components provided from higher layers

Is a parameter consisting of the sum of

. J = 1 for NPUSCH (re) transmission corresponding to a dynamically scheduled grant and j = 2 for NPUSCH (re) transmission corresponding to a random access response grant,

. If the enhanced random access power control is not applied,

Where the parameter preambleInitialReceivedTargetPower [8] (

) And

The cell

Signals from the upper layer for serving. When enhanced random access power control is applied,

[Equation 8]

to be.

Here, j = 1, in NPUSCH format 2

= 1; In NPUSCH format 1

Serving cell

It is provided in the upper layer. If j = 2,

= 1.

The cell

And

= nrs-Power + nrs-PowerOffsetNonAnchor-downlink path loss estimate calculated by the UE for NRSRP, where nrs-Power is provided by the upper layer and subsection 16.2.2.2 and nrs-power-offsetNonAnchor is by the upper layer If not provided, it is set to 0.

Power headroom

When the UE transmits NPUSCH for cell serving in NB-IoT UL slot i, power headroom is calculated using:

[Equation 9]

here,

,

, And

It is defined in Subclause 16.2.1.1.1.

The power headroom should be rounded to the nearest value from [PH1, PH2, PH3, PH4] dB of the set as defined in [10], and transmitted to the upper layer by the physical layer.

The above salpin contents (3GPP system, frame structure, NB-IoT system, etc.) can be applied in combination with the methods proposed in the specification, which will be described later, or supplemented to clarify the technical characteristics of the methods proposed in the specification. Can be.

Narrow band (NB) -LTE is a system for supporting low complexity and low power consumption with a system bandwidth corresponding to 1 PRB of an LTE system. This can mainly be used as a communication method for implementing an Internet of Things (IoT) by supporting devices such as machine-type communication (MTC) in a cellular system.

By using OFDM parameters such as the LTE subcarrier spacing of the existing LTE, the advantage is that the frequency can be efficiently used by allocating 1 PRB to the legacy LTE band for NB-LTE without additional band allocation. In the case of downlink, the physical channel of the NB-LTE is defined as NPSS / NSSS, NPBCH, NPDCCH / NEPDCCH, NPDSCH, etc., and N is added to distinguish it from LTE.

Semi-permanent scheduling (SPS) has been introduced and used in legacy LTE and LTE eMTC. The first terminal receives SPS configuration setup information through RRC signaling. Subsequently, when the terminal SPS activation DCI (with SPS-C-RNTI) is received, the SPS operates using the SPS configuration information received through RRC signaling, resource scheduling information included in the DCI, and MCS information. When the UE receives the SPS release DCI (with SPS-C-RNTI), the SPS is released. Thereafter, when SPS-activated DCI (with SPS-C-RNTI) is received again, the SPS operates as described above. If, after receiving the SPS release DCI (with SPS-C-RNTI), the UE receives the SPS configuration release information through RRC signaling, the UE receives the SPS configuration setup information again (SPS-C-RNTI value). SPS activation DCI cannot be detected.

The meaning of the phrase 'monitor the search space' used in this specification is to decode NPDCCHs of a specific area according to the DCI format to be received through the search space, and then scrambling the CRC to a specific RNTI value previously promised. It means the process of checking whether the desired value is correct. Additionally, in the NB-LTE system, since each UE recognizes a single PRB as each carrier, it can be said that the PRB referred to in this document has the same meaning as a carrier. DCI formats N0, N1, and N2 referred to in this document refer to DCI formats N0, N1, and N2 in the 3GPP TS 36.212 [2] standard.

In addition, the contents of the above salpin (3GPP system, frame structure, NB-IoT, MTC system, U-Band system system, etc.) can be applied in combination with the methods proposed in the specification, which will be described later, or proposed in the specification. It can be supplemented to clarify the technical characteristics of the methods.

In addition, contents related to the preconfigured uplink resource (PUR) to be described later (Half DMRS design for PUR, DMRS orthogonality for PUR transmission, interlace definition method based on the entire CC BW, interlace definition method based on LBT-SB, CFS The PUR and CBS PUR integrated solutions, etc.) are related to uplink transmission, and can be equally applied to the uplink signal transmission method in the aforementioned NB-IoT system, MTC system, and U-Band system (unlicensed band). In addition, it is of course possible to modify or replace the technical ideas proposed in the present specification to meet terms, expressions, and structures defined in each system so that they can be implemented in the corresponding system.

For example, uplink transmission through PUR, which will be described later, may be performed in L-cells and / or U-cells defined in the U-Band system.

The above-described methods (for example, the methods described in the first to third embodiments) basically include one LTE (e.g., NR base station) LTE NB-IoT system and / or LTE eMTC system in the NR band. This is the proposed method to support.

However, the above-described methods (for example, the methods described in the first to third embodiments) may be provided by two different base stations (eg, LTE base station and NR base station) coexisting while providing their respective services. It can be extended. That is, the above-described methods may be considered for optimization even when the NR base station supports the NR system and the LTE base station coexists in the frequency band while supporting the NB-IoT system or the eMTC system.

Further, as mentioned above, the above-described methods (for example, the methods described in the first to third embodiments) are used when the NB-IoT system and / or (e) the MTC system coexist with the NR system. Of course, each independently applied, or two or more methods can be applied in combination (ie, combined).

35 (A) shows an example of an operation flowchart of a terminal performing idle mode PUR transmission of one or more physical channels / signals to which the method proposed in this specification can be applied.

35 (A) is for convenience of description only and does not limit the scope of the present invention.

As shown in FIG. 35 (A), first, the terminal receives configuration information for a preset uplink resource (PUR) (S2501).

Then, the terminal transmits uplink data in the idle mode (S2503).

Finally, when the terminal receives the retransmission instruction, step S2503 is performed again, and if the retransmission instruction is not performed, the operation ends (S2505).

35 (B) shows an example of an operation flowchart of a base station performing idle mode PUR transmission of one or more physical channels / signals to which the method proposed in this specification can be applied.

35 (B) is for convenience of description only and does not limit the scope of the present invention.

As shown in FIG. 35 (B), the base station transmits configuration information for a preset uplink resource to the terminal (S2507).

Subsequently, the base station receives uplink data from the idle mode terminal (S2509).

Finally, when the base station transmits the retransmission instruction to the terminal, step S2509 is performed again, and if the retransmission instruction is not transmitted, the operation ends (S2511).

36 is for convenience of description only and does not limit the scope of the present invention.

As shown in FIG. 36, the base station transmits configuration information for a preset uplink resource to the terminal (S2601).

Subsequently, the terminal transmits uplink data to the base station in the idle mode (S2603).

37 is for convenience of description only and does not limit the scope of the present invention.

37 (a) is a flowchart illustrating a method for transmitting an uplink of a terminal.

37 (b) is a flowchart illustrating a downlink reception method of the terminal.

38 is for convenience of description only and does not limit the scope of the present invention.

38 (a) is a flowchart illustrating a method of receiving an uplink of a base station.

38 (b) is a flowchart illustrating a downlink transmission method of the base station.

39 is for convenience of description only and does not limit the scope of the present invention.

39 (a) is a flowchart illustrating a method of transmitting and receiving uplink data between a base station and a terminal, and FIG. 39 (b) is a flowchart illustrating a method of transmitting and receiving downlink data between a base station and a terminal.

The contents to be described later may be applied to a U-Band system in combination with a structure of an uplink and downlink channel and a wireless communication system supporting the salpin unlicensed band.

For example, a DMRS design described later for transmission and reception of signals in an L-cell and / or a U-cell may be defined.

[First Embodiment]

In the first embodiment, a half-DMRS design method is proposed.

The DMRS sequence for transmitting 12 subcarriers or 6 subcarriers NPUSCH transmitted by the terminal to the base station is composed of a 12-length sequence and a 6-length sequence, respectively.

That is, the number of subcarriers through which the terminal transmits data to the base station and the length of the DMRS sequence are set to be the same.

40 is an example of an existing operation in which NPUSCH and DMRS sequences transmitted to 12 subcarriers occupy time / frequency resources, an example in which a terminal uses an N / 2 length DMRS in transmitting uplink data, and different Half DMRS Shows the frequency hopping pattern between.

In the case of FIG. 40 (A), as a method of increasing the UE multiplexing capability of the PUR operating in the idle mode, the base station may allocate a half DMRS occupying only half of the subcarriers occupied by the legacy DMRS sequence to the UE. . That is, a method in which a terminal intending to transmit uplink data (NPUSCH) on N subcarriers transmits an NPUSCH to a base station using an N / 2 length DMRS can be considered.

The basic sequence of the DMRS sequence used for NPUSCH transmission can be defined as shown in Tables 33 and 34 for 6 subcarriers and 3 subcarriers, respectively.

Table 33

Table 34

That is, when transmitting NPUSCH to N subcarriers (for example, when N = 12 or 6), the terminal may use an N / 2 length DMRS.

40 (B) illustrates an example in which a terminal uses DMRS of N / 2 length in transmitting uplink data.

As shown in FIG. 40 (B), the base station may instruct / set the UE to use the DMRS sequence based on the 6 length-based sequence in Table 34.

As described above, when the base station instructs / sets the terminal to use the N / 2-length DMRS, the NB-IoT terminal is located where the channel change is not large, so performance degradation is small when estimating the channel using Half DMRS. In addition, when the terminal uses half DMRS as described above, there is an advantage that the terminal can concentrate and use the power of the RE that does not transmit the DMRS to the RE that transmits the DMRS. In addition, when the base station allocates resources to the terminal, it is possible to reuse the existing sequence without introducing a new sequence. In addition, compared to comb type DMRS, there is a benefit in terms of PAPR.

Here, frequency hopping between 1 ^st half and 2 ^nd half of FIG. 40 (B) may be performed.

Here, the base station may set the frequency hopping pattern to be cell-specific, CE level specific, or UE specific.

40 (C), the base station / terminal may use a frequency hopping pattern between different Half DMRSs.

The base station can multiplex multiple terminals to the same uplink resource using dedicated DMRS.

FIG. 42 shows an example in which two UEs are multiplexed in FIG. 41.

As shown in FIG. 42, DMRS may be FDM characteristically.

Here, an example of how the base station sets the frequency hopping pattern is as follows.

[Method 1 of the first embodiment]

The frequency hopping pattern is defined so that the base station is changed for every timing unit (e.g., slot, subframe, radio frame, repetition number, resource unit, etc.), and the base station can set the terminal to indicate that the start frequency offset is indicated by the base station.

In detail, when the UE starts the subcarrier to transmit the NPUSCH designated by the base station is SC _NS , and when the UE is configured to transmit the NPUSCH across N subcarriers, the location of the frequency resource of half DMRS is (SC _NS ) from the subcarrier to (SC _NS + N / 2-1) subcarrier. Here, the base station may additionally designate a starting frequency offset of half DMRS to the terminal.

Characteristically, the above can be indicated from the base station to the terminal through SIB or dedicated RRC signaling in 1 bits. That is, if the start frequency offset indicator is 0 (SC _NS ), the half DMRS is transmitted from the subcarrier to (SC _NS + N / 2-1) subcarrier. If the start frequency offset indicator is 1, (N / 2 + SC _NS ) The base station may configure the terminal to transmit half DMRS from the subcarrier to the (N / 2 + SC _NS + N / 2-1) subcarrier. It can be set that the transmission is performed in the first slot like this, and then the subsequent slots are changed and transmitted.

[Method 2 of the first embodiment]

From the (SC _NS ) subcarrier (SC _NS + N / 2-1) subcarrier, or (N / 2 + SC _NS ) subcarrier from (SC _NS ) subcarrier at a specific timing regardless of where the UE actually transmits the NPUSCH. / 2 + SC _NS + N / 2-1) The base station may indicate the subcarrier recognition to the terminal. In this case, the specific timing may be an even or odd slot, subframe, radio frame, repetition number, resource unit, or the like.

For example, if the base station is in the odd-numbered through the SIB or dedicated RRC signaling to 1bits second slot to transmit half the DMRS _(NS SC) from the sub-carrier (SC _NS + N / 2-1) sub-carrier indication to the UE, in the even-numbered subframes always (N / 2 + SC _NS) is equivalent to setting to the mobile station to transmit a half DMRS from the sub-carriers _{(N / 2 + SC NS +} N / 2-1) and subcarriers, and in this case the It may be of the form as shown in Figure 40 (C).

[Method 3 of the first embodiment]

Method 3 is a method in which a plurality of combinations are preset in a table according to a repetition number and a number of resource units in a frequency hopping pattern, and a base station instructs a user equipment of a specific index through SIB or dedicated RRC signaling.

In addition, when the 2 tone DMRS structure used in the eMTC is applied to the above proposed method (eg, method 1 and / or method 2), the base station may instruct the terminal to transmit the NPUSCH to the 4 subcarriers. That is, N = 4 and half DMRS is a two tone DMRS. Here, the proposed methods (for example, Method 1 and / or Method 2) can be applied to both of these methods (Method 3).

Also, the base station can apply the CDM to the DMRS-based sequence. In this case, the UE instructed by the base station to transmit the NPUSCH to the N subcarriers may select and transmit the DM length sequence of N length, where the base station may set to the terminal that the cover codes are composed of 0s and 1s.

For example, when N = 12, the DMRS cover code is set to {1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0} in order from low subcarrier to high subcarrier. If there is, the base station may be configured to the terminal that it is transmitted in the same shape as the drawings (for example, FIGS. 40, 41, 42 and / or 43). Even in this case, the base station can set the power of the RE having a cover code of 0 to the RE having a cover code of 1 to the terminal.

If the previously proposed method was actually a method of using an N / 2 length DMRS sequence, the method would be set to multiply half of them by using an N length DMRS sequence.

It has the same advantages as the previously proposed method, and the specific task can be simplified because only the cover code needs to be additionally instructed by the base station.

[Second Embodiment]

The second embodiment is a method for a base station to allocate resources to a terminal based on orthogonality between DMRSs.

For example, DMRS orthogonality, which will be described later, may be defined for transmission and reception of signals in L-cells and / or U-cells.

As an example of a method in which a plurality of terminals share time / frequency resources among preconfigured UL resources, there are non-competition sharing PUR and contention-based sharing PUR. Both of these methods can be considered to be similar in that a plurality of UEs share a specific resource to transmit UL resources.

However, assuming that the DMRS sequence is selected based on the prior art, when UE1 and UE2 are configured to transmit PUR using 12 subcarriers and 6 subcarriers, respectively, as shown in FIG. 43, UL resources in which UE1 and UE2 are multiplexed In orthogonality of the DMRS sequences used by the two UEs may not be maintained.

Therefore, the following methods according to the second embodiment are proposed to solve the above problems. The proposed methods are mainly described for NB-IoT, but can be applied to other systems as well as eMTC.

[Method 1 of the second embodiment]

Method 1 of the second embodiment is a method in which a base station instructs a terminal of a number of subcarriers that can be transmitted for each preset uplink resource. Particularly, the base station may set the terminal to inform the user of the setting when the first uplink resource is initially set, and the base station may instruct the terminal by cell specification, CE level specification, not resource specification.

For example, in the case of non-competitive PUR (ie, CFS PUR), the base station may initially configure a plurality of preset uplink resources and inform the UEs through system information (eg, SIB-NB). A total of PUR _MAX can be configured from PUR index 0 to PUR index PUR _MAX -1.

At this time, the base station may inform the UEs of the number of subcarriers that can be transmitted for each preset uplink resource through the aforementioned system information. Here, the UL carrier index to which each PUR will be transmitted can be independently set by the base station to the terminal.

Subsequently, the base station may indicate a PUR index among PUR _MAX PURs to a UE to perform PUR through UE-specific RRC signaling, along with DMRS sequence information (eg, basic sequence index), RNTI information, and repetition number. It can be set to notify. For example, in the case of contention-based PUR (ie, CBS PUR), the base station may initially configure a plurality of preset uplink resources and inform the UEs through system information (eg, SIB-NB).

At this time, the base station may inform the UEs of the number of subcarriers that can be transmitted for each preset uplink resource, and the DMRS sequence set, RNTI set, etc. through the aforementioned system information.

Subsequently, the UE selects or randomly selects a PUR to be transmitted by the UE according to a predetermined rule, transmits uplink data using the number of subcarriers that can be transmitted in the PUR, and pre-promises one of the DMRS sequence sets. UL data may be transmitted according to a rule or randomly selected.

However, when operating as described above, a situation in which a plurality of UEs share time / frequency resources does not occur as shown in FIG. 43, and the orthogonality of the DMRS may be maintained while the UE uses the legacy DMRS.

[Method 2 of the second embodiment]

Unlike method 1 in which a base station instructs to use the same number of subcarriers when a plurality of UEs share all or part of UL time / frequency resources in order to maintain DMRS orthogonality, method 2 uses a plurality of UEs for UL time / frequency resources This is a method that allows a different number of subcarriers to be used even if all or a part is shared.

As shown in FIG. 44, UE 1 uses time resources by T1 + T2 and frequency resources by F1 + F2, and UE 2 can use time resources by T2 + T3 and frequency resources by F2 + F3. have.

Accordingly, two UEs can share UL resources by T2 on the time axis and T2 on the frequency axis.

Here, in order to maintain orthogonality of the DMRS sequence, the base station may set the length of the DMRS sequence to be used by each terminal to be different according to a time axis (e.g., per slot or per subframe). That is, the base station can be set to indicate the length of the DMRS sequence to be used for the time unit shared by a plurality of terminals (eg, [T2] region of FIG. 34) because it can know how the terminals to be scheduled are shared. .

There may be various ways in which the base station indicates the length of the DMRS sequence to the UE, but for example, the base station determines the length of the DMRS sequence for each subframe frame of 10 ms for the UE for {12, 12, 6, 6, 6, 6, 6, 3 , 3, 12, 12} (in this case, if the corresponding number indicates the length of the DMRS sequence), the terminal sets different tables (eg, 12 length table, 6 length table) defined in the prior art according to the indicated DMRS sequence length. , 3 length table), and may be set to select the final DMRS sequence using the base sequence index indicated by the base station.

In this case, if the number of subcarriers for UL data transmission of a specific terminal is N and the DMRS sequence length indicated by the base station is M, the terminal sets the DMRS sequence of length M in the corresponding time unit (subframe or slot) onto the frequency domain. It can be set to transmit N / M times repeatedly.

Characteristically, the base station may repeatedly transmit the DMRS sequence of length M used for the repetitive transmission while the same DMRS sequence changes the cyclic shift value, and the terminal k + from the kth base sequence when the indicated base sequence index is k. It can be configured to the terminal that the N / M -1 th base sequence is connected in sequence and transmitted.

In addition, the base station may set the terminal to determine the length of the DMRS sequence based on the UE occupying the smallest number of subcarriers in the corresponding time unit. That is, when UE 1 occupying 3 subcarriers and UE 2 occupying 6 subcarriers and UE 3 occupying 12 subcarriers are multiplexed in a specific subframe (s), the base station UE selects a 3 length DMRS sequence. In addition to 1, it can be set to indicate to UE 2 and UE 3.

If a specific example is shown through a picture, it may be as shown in FIGS. 45 and 46. That is, UE 1 may transmit UL data to the base station using 12 subcarriers during the K subframe and the K + 1 subframe. In addition, when the UE 2 transmits UL data using 6 subcarriers in the K + 1 subframe and the K + 2 subframe, the base station may indicate DMRS sequence length information to the UE 1 as {12, 6}. have.

The base sequence (e.g. root index) for generating each DMRS sequence transmitted in concatenated above may be set to a different value, and / or a cyclic shift may be set to a different value. Through this, the effect of lowering the PAPR can be obtained.

[Method 3 of the second embodiment]

Method 3 is a method of designing or combining a DMRS sequence having a new principle described below.

When the base station instructs the terminal to the L-length DMRS sequence in a sequence that the terminal can use for CFS PUR or CBS PUR and maintain DMRS orthogonality at all times, the terminal generates a k * L-length DMRS sequence by concatenating the corresponding DMRS sequence k times. can do. For example, L may be 3, and k may be 2 or 4, the base station may generate a DMRS sequence of length 6 and length 12.

When DMRS is designed in this way, even if the UE selects one of the k * L length DMRS sequences and transmits the PUR to a specific PUR, it can always maintain orthogonality with the k '* L length DMRS sequence of other UEs sharing it. do.

Considering the case of using the legacy 3-length DMRS sequence in the simplest way, it is as follows. For example, it can be set to the terminal that the base station generates a length 6 DMRS sequence as shown in Table 36 by a combination of legacy 3 length DMRS sequences as shown in Table 35. This example is created by concatenating the base sequence index +1 after the base sequence index is even, and concatenating the base sequence index -1 when the base sequence index is odd.

In addition, it may be set to the terminal that the base station instructs such a combination method. That is, it may be defined to determine the next base sequence index according to a specific rule from the base sequence index initially indicated by the base station. For example, if the base station instructs the terminal to set the interval between base sequence indexes to 6 and wraparound the UE when the total number is exceeded, the base sequence index 0 and the base sequence index 6 can be set, and the base sequence is 10 and The base sequence index 4 (ie, 10 + 6 mod 12) can be concatenated with each other. In addition, it is also possible to consider a method in which a terminal transmits the same DMRS sequence twice.

This configuration has the advantage that the terminal can maintain orthogonality with the length 3 DMRS sequence even if it uses any of the length 6 DMRS sequences defined in Table 35, but has a disadvantage in that the PAPR performance deteriorates. The base sequence (e.g. root index) for generating each DMRS sequence transmitted in concatenated above may be set to a different value, and / or a cyclic shift may be set to a different value. Through this, the effect of lowering the PAPR can be obtained.

Table 35

Table 36

If the method 3 is further described, the base station may set the base sequence length of the DMRS sequence to the UE differently from the number of frequency REs for data in the corresponding UL resource. That is, the base station can set the terminal that the base sequence length is selected based on the minimum number of frequency REs overlapping with a plurality of terminals sharing time / frequency UL resources.

Subsequently, a method in which the terminal extends and uses an actual DMRS sequence as in the above method may be considered. In this case, the base sequence index of the extended DMRS sequence may be different, and the cyclic shift value may be set differently.

[Method 4 of the second embodiment]

In method 4, a method of using short DMRS (e.g., Half DMRS) proposed in the first embodiment for DMRS orthogonality may be considered.

That is, the base station can be set to indicate that the time unit (eg, slot, subframe, etc.) that should use the short DRMS, and if the short DMRS should be used for each time unit, the length of the corresponding short DMRS can be indicated to the UE, and the corresponding information It may be set that the UE instructed to transmit the DMRS sequence using one of the base sequence indices corresponding to the indicated length by applying it to the corresponding subframe.

At this time, if the corresponding short DMRS is used, power to be used for the remaining REs can be used, so if the length of the short DRMS is K and the number of frequency REs capable of transmitting UL data is L, the UE determines the power per each RE of the short DMRS. The base station can be set to the terminal to transmit by increasing the existing L / K times. For example, if the short DRMS length is 6 and the number of frequency REs capable of transmitting UL data is 12, the UE may transmit to the base station by increasing power per each RE of the short DMRS by 12/6 = 2 times. .

In addition, when a plurality of UEs share a specific time / frequency resource, the base station may instruct the UEs of the short DMRS length based on the UE transmitting UL data to the smallest frequency RE (s) among the UEs. . For example, in the same subframe, UE1 is configured to transmit UL data from # 0 SC to # 2 SC, UE2 from # 0 SC to # 6 SC is configured to transmit UL data, If the UE3 is configured to transmit UL data from # 0 SC to # 11 SC, the base station can be configured to instruct UE2 and UE3 to use a 3-length DMRS sequence, UE2 3dB boost, UE3 6dB boost Can be set to

As shown in FIG. 47, UE 1 transmits UL data using 12 subcarriers during K subframes and K + 1 subframes, and UE 2 transmits 6 subframes in K + 1 subframes and K + 2 subframes. When transmitting UL data using a carrier, the base station may instruct the UE 1 that the length of the subframe information and the short DMRS is 6, which is to use short DMRS, such as {0, 1}.

The proposed method has an advantage in that only the DMRS sequences can be used without repetitive transmission to maintain DMRS orthogonality.

Hereinafter, the RE group-related interlace structure for UL transmission will be described with an NR-U (unlicensed band) (or U-Band) system as an example, but the following description is the same for the aforementioned NB-IoT and MTC systems. Of course it can be applied. In the NR-U (Unlicensed band) system, considering the regulation related to OCB (Occupied Channel Bandwidth) and PSD (Power Spectral Density), a unit RE group consisting of K REs consecutive in frequency phase is defined, and in frequency phase As a set of discontinuous N unit RE groups (with equal intervals), a minimum resource for transmission of one UL channel can be defined. A set of N unit RE groups may be defined as a unit interlace, and based on this, a single UL channel transmission resource may be configured / configured as a single or multiple unit interlaces.

On the other hand, in constructing / generating a DMRS sequence for a UL channel (for example, PUCCH or PUSCH) based on this RE group interlace type in NR-U, a principle similar to the proposed method may be applied, and specifically The explanation is as follows. In the following, PUCCH is mainly described for convenience, but is not limited thereto, and can also be applied to configuration / generation of sequences (eg, carrying DMRS or UCI) used for other UL channels / signals (eg, PUCCH or PUSCH or SRS). Do.

[Method 5 of the second embodiment]

Even if PUCCH (s) (of different UEs) configured with different unit interlace numbers in the NR-U overlap with each other, orthogonality of DMRS sequences transmitted by UEs may have to be guaranteed.

Therefore, similar to the principle of [method 3], in method 5 of the second embodiment, the base station / terminal sets the DMRS sequence length to unit RE group size K (eg, 6 subcarriers or 12 subcarriers, which is the (minimum) consecutive RE number. When the number of (minimum) unit RE groups that can be defined / generated as length-K, which is the same length as that of the same length, and can fit into one unit interlace-based PUCCH is N, the terminal performs DMRS sequence on the corresponding unit interlace-based PUCCH. In the case of constructing, a DMRS sequence of length-K equal to unit RE group size K (with equal intervals) may be discontinuously connected N times.

Additionally, when M unit interlaces are configured as one PUCCH resource, the UE may consider a form of concatenating the length-K DMRS sequence N × M times. That is, in method 5, it may be configured to generate / map / transmit DMRS sequences of individual length-K for each unit RE group belonging to one or a plurality of unit interlaces constituting one PUCCH resource.

For example, as illustrated in FIG. 48 (A), when unit RE group size K is 12 subcarriers and 3 unit RE groups constituting one unit interlace are considered as 3, UE1 has one unit interlace (index # The base station may configure UE1 to transmit the 12-length DMRS sequences individually generated in a state of being allocated as a single PUCCH resource (contiguously) three times in a concatenated manner.

On the other hand, in the case of UE2, the base station tells UE2 that 2 unit interlaces (indexes # 0 and # 1) are transmitted by concatenating 3 × 2 = 6 times of the 12-length DMRS sequence generated individually while being allocated as a single PUCCH resource. Can be set.

In the above case, orthogonality may be maintained because the DMRS sequences of UE1 and UE2 have the same length in # 0 interlaced PUCCH. Characteristically, the DMRS sequences used at this time can be independently selected, and cyclic shift or the like is used to maintain orthogonality between the same sequence indices. Meanwhile, in the above, the length-K DMRS sequences (constituting one PUCCH) may have a base sequence (eg root index) for generating a DMRS sequence for each unit RE group and / or for each unit interlace to a different value. And / or cyclic shift may be set to different values for each unit RE group and / or for each unit interlace (through this, an effect of lowering PAPR can be obtained).

[Method 6 of the second embodiment]

In method 6, the base station defines a value (K × N) multiplied by the unit RE group size K and the number of (minimum) RE groups N that constitute one unit interlace as a DMRS sequence length, and generates a DMRS sequence based on the same. , In the state that N DMRS sub-sequences (of length K) are created by dividing the length- (K × N) DMRS sequence into N equal parts, the base station sequentially maps different DMRS sub-sequences for each unit RE group / The base station can be configured to transmit to the terminal.

That is, in the case of method 6, in the state where the base station generates a DMRS sequence of individual length- (K × N) for each unit interlace for one or a plurality of unit interlaces constituting one PUCCH resource, this is divided into N equal ( It may be configured to sequentially map / transmit N DMRS sub-sequences of length K) to a plurality of unit RE groups belonging to a corresponding unit interlace.

In the case of FIG. 48 (B), when unit RE group size K is 12 subcarriers and the number of unit RE groups constituting one unit interlace is 3, for UE1, one unit interlace (index # 0) is single. The base station may configure the UE to generate one 12 × 3 = 36 length DMRS sequence in the state of being allocated as a PUCCH resource and map / transmit the sub-sequence divided into three into three unit RE groups, respectively.

In the case of UE2, two 12 × 3 = 36 length DMRS sequences are generated while two unit interlaces (index # 0 and # 1) are allocated as a single PUCCH resource, and the sub-sequence of the first DMRS sequence is divided into three. The base station may configure the UE to map / transmit sub-sequences of the second DMRS sequence into three unit RE groups belonging to the first unit interlace to three unit RE groups belonging to the second unit interlace, respectively.

In the above case, orthogonality may be maintained because the DMRS sequence of UE1 and UE2 used for # 0 interlaced PUCCH have the same length. Additionally, since the length of the DMRS length is increased, there is an advantage that the number of candidates can be increased.

Additionally, if the base station sets the number of unit RE groups constituting one interlaced PUCCH to a specific UE to an integer (eg L) times N, the UE defines (K × N) value as the DMRS sequence length according to the above method. Based on the base station, L DMRS sequences are individually generated, and the base station is specified to map / transmit L DMRS sequences by sequentially applying the above method to N unit RE group units for all (N × L) unit RE groups. It can be configured for the UE.

In this case, the L DMRS sequences may be set independently of each other, or may be used by setting different cyclic shift values of the same DMRS sequence. In this setting, even if the number of unit RE groups that can fit in one interlaced PUCCH is different, orthogonality of the DMRS sequence can be maintained because the DMRS sequence length is set the same.

Meanwhile, in the DMRS sequences of length- (K × N) (constituting one PUCCH), a base sequence (eg root index) for generating a DMRS sequence for each unit interlace may be set to a different value, and / or Alternatively, the cyclic shift may be set to a different value for each unit interlace (through this, an effect of lowering PAPR can be obtained).

K mentioned above may be the number of REs to which DMRS is mapped in the unit RE group. For example, when the total number of REs in the unit RE group is 12, DMRSs (such as comb type DMRSs) may be set to 6 when mapped to 6 odd-numbered REs or 6 even-numbered REs.

As mentioned above, the interlace structure is considered for UL transmission in NR-U. At this time, the following alternatives (alt X) can be considered in defining the interlace structure.

For example, as method 7 of the second embodiment, a method of defining an interlace based on the total component carrier (CC) bandwidth (BW) may be considered.

For example, as method 8 of the second embodiment, a method of defining interlaces on the basis of a list before talk sub-band (LBT-SB) may be considered.

If the CC bandwidth is 80 MHz and the LBT-SB is 20 MHz, since the phenomenon and the problems that arise are different depending on whether to define an interlace based on 80 MHz or 20 MHz, this specification will Suggests a solution.

The contents to be described later may also be applied to the salpin NB-IoT system and the MTC system.

For example, the UL interlace structure, which will be described later, may be applied in combination with DMRS design-related content in the salpin NB-IoT system, for example.

[Method 7 of the second embodiment]

Method 7 of the second embodiment is a method in which a base station / terminal defines an interlace index and an RB set constituting each interlace based on the total CC bandwidth.

For example, when an interlace is defined based on a CC bandwidth of 80 MHz and a BWP (bandwidth part) of 40 MHz smaller than the CC bandwidth is set to the UE, 40 MHz of all interlaces spanning 80 MHz Only part of it will be available to the UE.

In addition, based on the (multiple) 20 MHz LBT-SB smaller than the BWP, the UL transmission resource of the UE (during interlace spanning 80 MHz) is a specific (or all) BBT (or all of the BWP) -Only the part corresponding to SB can be allocated.

If 30kHz subcarrier spacing is assumed, a total of 217 RBs exist at 80 MHz, and if the interval between RBs in the interlace is set to N (eg, 5 RB), X interlaces are (discontinuous).

It consists of (eg, 44) RBs and NX interlaces (discrete)

It may consist of (eg, 43) RBs.

If an SB smaller than the CC bandwidth is allocated to the UE, only a portion corresponding to the bandwidth of the corresponding SB can be allocated to the UE, and only a portion of the configured interlaces can be used.

In this situation, how to define the DMRS sequence length in the corresponding UL interlace structure, how to create it, and how to divide it and map it as follows can be summarized as follows.

[Method 7-1 of the second embodiment]

Method 7-1 of the second embodiment is a method in which the base station sets the DMRS sequence length to the UE equal to one RB size (i.e., 12 REs).

In this case, for example, assuming that one interlace is composed of (discontinuous) N RBs based on the bandwidth of a single SB, a total of N length-12 sequences are mapped at equal intervals to configure DMRS, and thus the base station configures the DMRS. Can be set. That is, assuming the same subcarrier spacing (eg, 30 kHz) and interlace allocation (eg, interlace RB interval is 5 PRB), when one SB has a bandwidth of 20 MHz, one interlace is 10 (discontinuous). Or, since it is composed of 11 RBs, the base station may configure the terminal to configure 10 or 11 length-12 sequences to form a DMRS according to the interlace index.

As shown in FIG. 49 (A), 11 interlace index # 0 of sub-band # 0 constitutes DMRS of 11 length-12 sequences, and interlace index # 1 and # 2 contain 10 length-12 sequences. It comprises DMRS.

11 interlace index # 1 of sub-band # 1 constitutes DMRS of 11 length-12 sequences, and 10 length-12 sequences of interlace index # 0 and # 2 constitute DMRS.

In FIG. 49 (A), the number of guard bands may be five, and the terminal may use five guard bands, and accordingly, the first interlace index of sub-band # 1 is # 1.

[Method 7-2 of the second embodiment]

Method 7-2 of the second embodiment is a method in which the base station sets the DMRS sequence length to the terminal equal to the size of one interlace in each SB.

In this case, for example, assuming that M SBs are allocated to the UE, K interlaces are allocated within each SB, and one interlace is composed of (discrete) N RBs based on the bandwidth of a single SB, the total The base station may configure the terminal that (M x K) length- (12 x N) sequences constitute the DMRS. That is, assuming the same subcarrier spacing (eg, 30 kHz) and interlace allocation (eg, interlace RB interval is 5 PRB) as above, it is assumed that two SBs are allocated to the UE, and the bandwidth of a single SB is 20 MHz and interlace If the RB interval is 5 PRB, assuming that 3 interlaces are allocated because 5 interlaces can be allocated in each SB, since one interlace is composed of 10 (or discontinuous) RBs, the interlace index Accordingly, the base station may set to the terminal that a total of (2 x 3) length- (12 x 10) sequences or length- (12 x 11) sequences constitute DMRS. For example, it may be a structure in which K sequences are mapped for each SB.

As shown in FIG. 49 (B), the UE generates a sequence of 1 length- (11 x 12) for interlace index # 0 of Sub-band # 0 and divides the sequence into 11 PRBs for mapping. DMRS is constructed by dividing (ie, 12 REs) into each PRB, and interlace indexes # 1 and # 2 generate one length- (10 x 12) sequence, and divide them into 10 PRBs. For this, DMRS is configured by dividing the sequence into 10 equal parts (ie, 12 REs) and mapping to each PRB.

On the other hand, interlace index # 1 of sub-band # 1 generates 1 length- (11 x 12) sequence, and divides the sequence into 11 equal parts (ie, 12 REs) to map to each PRB to divide into 11 PRBs. DMRS is constructed in the same way, and interlace indexes # 0 and # 2 generate one length- (10 x 12) sequence, and divide the sequence into 10 equal parts to divide it into 10 PRBs (ie, 12 REs each. ) DMRS is configured by mapping to each PRB. Characteristically, when mapping the sequence by dividing each 12RE, it can be set to map in the lowest PRB order corresponding to the same interlace in each sub-band.

In FIG. 49 (B), the number of guard bands may be five, and the terminal may use five guard bands, and accordingly, the first interlace index of sub-band # 1 is # 1.

[Method 7-3 of the second embodiment]

Method 7-3 of the second embodiment is a method of setting the DMRS sequence length equal to the (multiple) interlace size allocated in each SB.

In this case, for example, assuming that M SBs are allocated to the UE, and K interlaces are allocated to each SB, and one interlace is composed of (discrete) N RBs based on the bandwidth of a single SB, the UE It can be set that a total of M length- (K x 12 x N) sequences constitute DMRS.

In addition, when the number of RBs forming an interlace is set differently for each interlace (ie, L interlaces are composed of N + 1 RBs, and KL interlaces are composed of N RBs), the total length of M- The {(KL) x 12 x N + L x 12 x (N + 1)} sequences configure the DMRS so that the base station can configure the terminal. That is, assuming the same subcarrier spacing (eg, 30 kHz) and interlace allocation (eg, interlace RB interval is 5 PRB) as above, it is assumed that two SBs are allocated to the UE, and the bandwidth of a single SB is 20 MHz and interlace If the RB interval is 5 PRB, assuming that 3 interlaces are allocated because 5 interlaces can be allocated in each SB (in this case, 3 interlaces allocated to each sub-band, 1 interlace is (discontinuous) 11 It consists of 10 RBs, two interlaces (assuming that it is composed of 10 discontinuous RBs), and a total of 2 length- (2 x 12 x 10 + 1 x 12 x 11) sequences constitute a DMRS. Can be set for this terminal. That is, one sequence may be mapped to each SB.

As shown in FIG. 49 (C), since sub-band # 0 is allocated interlace # 0 composed of 11 RBs and interlace # 1, # 2 composed of 10 RBs, a total length of 1- (2 x Create a sequence of 12 x 10 + 1 x 12 x 11), divide the sequence into (2 x 10 + 1 x 11) and divide them into (2 x 10 + 1 x 11) PRBs (ie, 12 RE) Each) configures DMRS by mapping to each PRB.

On the other hand, sub-band # 1 is interlace # 1 composed of 11 RBs and interlace # 0, # 2 composed of 10 RBs, so a total of 1 length- (2 x 12 x 10 + 1 x 12 x 11) DMRS by dividing the sequence (2 x 10 + 1 x 11) and mapping it to each PRB by dividing the sequence (2 x 10 + 1 x 11) to map them to (2 x 10 + 1 x 11) PRBs. Make up.

In addition, when the corresponding sequence is divided and mapped by 12RE, the base station may set the terminal to map in the lowest PRB order corresponding to the interlace allocated for each sub-band.

In FIG. 49 (C), the number of guard bands may be 5, and the terminal may use 5 guard bands, and accordingly, the first interlace index of sub-band # 1 is # 1.

[Method 7-4 of the second embodiment]

Method 7-4 of the second embodiment is a method of setting the DMRS sequence length equal to the size of one interlace in the allocated SB (group).

In this case, for example, assuming that M SBs are allocated to the UE, K interlaces are allocated within each SB, and one interlace is composed of (discrete) N RBs based on the bandwidth of a single SB, the total The base station can configure the terminal that the K length- (M x 12 x N) sequences constitute the DMRS.

In addition, when the number of RBs forming an interlace for each sub-band is set differently for each interlace index (ie, L interlaces are composed of a total of M x (N + 1) RBs for M SBs allocated to the UE) , P interlaces are composed of a total of M x N RBs in the M SBs allocated to the UE, and K- (L + P) interlaces are N in the Z SBs among the M SBs allocated to the UE. L1 interlaces are composed of +1 RBs and MZ SBs are each composed of N RBs.) L interlaces span lengths of M SBs using a length- {M x 12 x (N + 1)} sequence. The base station can be set to the terminal by configuring the DMRS, and the P interlaces can be set by the base station to the terminal by configuring the DMRS across the M SBs using the length- {M x 12 x N} sequence, and the K- ( L + P) interlaces are DMRS across M SBs using the length-[{Z x 12 x (N + 1)} + {(MZ) x 12 x N}] sequence The base station may be set to the UE that configuration.

That is, assuming the same subcarrier spacing (eg, 30 kHz) and interlace allocation (eg, interlace RB interval is 5 PRB) as above, it is assumed that two SBs are allocated to the UE, and the bandwidth of a single SB is 20 MHz and interlace If the RB interval is 5 PRB, assuming that 3 interlaces are allocated because 5 interlaces can be allocated in each SB. Since one interlace is composed of 10 (or discontinuous) RBs in each SB, According to the interlace index, the base stations say that the length- (2 x 12 x 10) sequences, or the length- (2 x 12 x 11) sequences, or the length- (1 x 12 x 10 + 1 x 12 x 11) sequences constitute the DMRS. Can be set for this terminal. That is, one sequence per single interlace spanning over M SBs may be mapped.

As shown in FIG. 50, a total of 3 interlaces are allocated over 2 sub-bands, and interlace indexes # 0 and # 1 among 3 interlaces total (1 x 10 + 1) over 2 sub-bands. Since it is composed of x 11) RBs, the terminal generates a total of 1 length- (1 x 12 x 10 + 1 x 12 x 11) sequences, and is divided and mapped to (1 x 10 + 1 x 11) PRBs. To do this, DMRS is configured by dividing the sequence (1 x 10 + 1 x 11) into equal parts (ie, 12 REs) and mapping to each PRB.

Here, since the interlace index # 2 is composed of a total of (2 x 10) RBs across 2 sub-bands, the terminal generates a total of 1 length- (2 x 12 x 10) sequences, and (2 x 10) DMRS is configured by dividing the sequence (2 x 10) into equal parts (ie, 12 REs) and mapping to each PRB in order to divide and map the number of PRBs.

In addition, when the corresponding sequence is divided and mapped by 12RE, the base station may configure the terminal to map in the lowest PRB order corresponding to the same interlace spanning over two sub-bands.

In FIG. 50, the number of guard bands may be 5, and the terminal may use 5 guard bands, and accordingly, the first interlace index of sub-band # 1 is # 1.

[Method 7-5 of the second embodiment]

Method 7-5 of the second embodiment is a method in which the base station sets the DMRS sequence length to the terminal in the same manner as the allocated (plural) interlace size in the allocated SB (group).

Here, the guard band (band between Sub-band # 0 and Sub-band # 1) may be 5PRB. In this case, for example, assuming that M SBs are allocated to the UE, and K interlaces are allocated to each SB, and one interlace is composed of (discrete) N RBs based on the bandwidth of a single SB, the UE It can be set that one length- (K x M x 12 x N) sequence constitutes DMRS over the entire SB allocated to.

Here, when the number of RBs forming an interlace for each sub-band is set differently for each interlace index (ie, L interlaces are composed of a total of M x (N + 1) RBs for M SBs allocated to the UE) , P interlaces are composed of a total of M x N RBs in the M SBs allocated to the UE, and K- (L + P) interlaces are N in the Z SBs among the M SBs allocated to the UE. If it consists of +1 RB and MZ SB each consists of N RBs) 1 length- (L x M x 12 x (N + 1) + P x M x 12 x N + {K -(L + P)} x {Z x 12 x (N + 1) + (MZ) x 12 x N}] can be set to configure DMRS for all interlaces allocated across M SBs using the sequence have.

That is, assuming the same subcarrier spacing (eg, 30 kHz) and interlace allocation (eg, interlace RB interval is 5 PRB) as above, it is assumed that two SBs are allocated to the UE, and the bandwidth of a single SB is 20 MHz and interlace If the RB interval is 5 PRB, assuming that 3 interlaces are allocated because 5 interlaces can be allocated in each SB. Since one interlace is composed of 10 (or discontinuous) or 11 RBs, the entire 1 length- (3 x 2 x 12 x 10) sequence, or a length- (3 x 2 x 12 x 11) sequence, or a length- (2 x 1 x 12 x 11 + 1 x 1 x 12 x 10) sequence Or, it can be set that the length- (1 x 1 x 12 x 11 + 2 x 1 x 12 x 10) sequences constitute the DMRS. That is, it may be a structure in which a total of 1 sequence is mapped over M SBs.

As shown in FIG. 51, 3 interlaces are allocated over 2 sub-bands, and interlace indexes # 0 and # 1 among 3 interlaces total (1 x 10 + 1 x over 2 sub-bands). Since 11) RBs and interlace index # 2 are composed of a total of (2 x 10) RBs over 2 sub-bands, the terminal has a total of 1 {1 x 2 x 12 x 10 + 2 x (1 x 12 x 11 + 1 x 12 x 10)} sequence, and {2 x (1 x 11 + 1 x 10) + 1 x 2 x 10} sequence to divide and map the sequence to { DMRS is constructed by dividing into 2 x (1 x 11 + 1 x 10) + 1 x 2 x 10} (ie, by 12 REs) and mapping to each PRB.

Here, when the corresponding sequence is divided and mapped by 12REs, the base station may set the terminal to map in the lowest PRB order of PRBs constituting all interlaces allocated to the UE over two sub-bands.

In the proposed methods 7-1 to 7-5, DMRS based on different options may be applied between different UL channels (e.g. PUSCH / PUCCH / SRS). For example, the method 7-1 or method 7-2 is applied to PUCCH / SRS, which is a channel based on multiplexing such as CDM / FDM, and the method 7-3, method 7-4, or method 7- is applied to PUSCH. It can be set to apply 5 methods. In addition, between the plurality of options, the RRC may be configurably operated, or dynamic switching may be supported through DCI (between long vs. short sequences).

In addition, in the proposed methods 7-1 to 7-5, for example, the terminal can select whether to use a guard band. For example, when the terminal selects to use a guard band, the terminal may report information that the HALF PRB can be used to the base station. Here, the base station may transmit configuration information (eg, a flag) to the terminal to use the guard band based on the information that the terminal can use the guard band. Then, the terminal may use the guard band for DMRS allocation based on the configuration information received from the base station.

In FIG. 51, the number of guard bands may be 5, and the terminal may use 5 guard bands, and accordingly, the first interlace index of sub-band # 1 is # 1.

When it is said that DMRS is generated according to the proposed method, the following DMRS randomization method may be required to reduce inter-cell interference.

As method 8-1 of the second embodiment, a method of applying DMRS sequence hopping (e.g. root / cyclic shift, scrambling ID / seed) based on the RB index in the entire CC bandwidth may be proposed.

As method 8-2 of the second embodiment, a method of applying DMRS sequence hopping based on the interlace index in the entire CC bandwidth may be proposed.

As method 8-3 of the second embodiment, a method of applying DMRS sequence hopping based on the SB index in the entire CC bandwidth may be proposed.

As method 8-4 of the second embodiment, a method of applying DMRS sequence hopping based on the RB index in the BWP may be proposed.

As method 8-5 of the second embodiment, a method of applying DMRS sequence hopping based on the interlace index in the BWP can be proposed.

As method 8-6 of the second embodiment, a method of applying DMRS sequence hopping based on the SB index in the BWP may be proposed.

As method 8-7 of the second embodiment, a method of applying DMRS sequence hopping based on the RB index in SB may be proposed.

As method 8-8 of the second embodiment, a method of applying DMRS sequence hopping based on the interlace index in SB may be proposed.

Here, when a single sequence is mapped across a plurality of RBs, DMRS sequence hopping may be applied based on the lowest RB index (and / or the lowest sub-band index) to which the corresponding sequence is mapped.

In the method 8-1 to 8-8 of the proposed second embodiment, the interlace index in each sub-band may vary according to the size of the guard band at the edge of each sub-band. That is, if the size of the guard band between sub-band # 0 and sub-band # 1 of the proposed options is K PRB, and the last interlace index value in sub-band # 0 is X, in sub-band # 1 The first interlace index can be (X + K + 1) mod M. At this time, M is the total number of interlaces present according to the subcarrier spacing value, and may be 10 at 15 kHz SCS and 5 at 30 kHz SCS.

For example, in a 30 kHz SCS situation, if K is 5 and X is 0, the first interlace index in sub-band # 1 may be (0 + 5 + 1) mod 5 = 1. As another example, in a 30 kHz SCS situation, when K is 3 and X is 0, the first interlace index in sub-band # 1 may be (0 + 3 + 1) mod 5 = 4.

As shown in FIG. 52 (A), three interlaces are allocated over two sub-bands, and interlace index # 0 of the three interlaces totals (1 x 10 + 1 x over two sub-bands). Since 11) RBs and interlace indexes # 1 and # 2 are composed of a total of (2 x 10) RBs over two sub-bands, the terminal has a total of {2 x 2 x 12 x To generate 10 + 1 x (1 x 12 x 11 + 1 x 12 x 10)} sequences, and map them by dividing them into {1 x (1 x 11 + 1 x 10) + 2 x 2 x 10} PRBs DMRS is constructed by dividing the sequence into {1 x (1 x 11 + 1 x 10) + 2 x 2 x 10} and mapping them to each PRB (ie, 12 REs).

Here, when the corresponding sequence is divided and mapped by 12RE, it can be set to map in the lowest PRB order of PRBs constituting all interlaces allocated to the UE over two sub-bands.

In addition, in the above options, when one terminal is instructed to perform UL transmission using a plurality of sub-bands, the terminal has a plurality of sub-bands (based on a sub-band index or a frequency band based on one guard). (Including a band), the UE may perform UL transmission using PRBs existing in a guard band between a plurality of sub-bands.

Therefore, if some or all of the PRBs included in the guard band are included in the interlace index allocated from the base station, the DMRS length also generates and maps the number of corresponding PRBs in the PRBs constituting the interlace in the sub-band. It can be set to the terminal.

FIG. 52 (B) shows an example of using PRBs present in the guard band in the method 7-5 having the interlace index of FIG. 52 (A).

As shown in FIG. 52 (B), three interlaces are allocated over two (continuous) sub-bands and guard bands, and all three (continuous) indexes # 0, # 1, and # 2 are two (continuous). Since it consists of (1 x 10 + 1 x 11) RBs across sub-band and guard bands, a total of {3 x (1 x 12 x 11 + 1 x 12 x 10)} sequences In order to create and divide it into {3 x (1 x 11 + 1 x 10)} PRBs, divide the corresponding sequence into {3 x (1 x 11 + 1 x 10)} and divide them (ie, by 12 REs). DMRS is configured by mapping to.

Here, when the corresponding sequence is divided and mapped by 12RE, it can be set to map in the lowest PRB order of PRBs constituting all interlaces allocated to the UE over two sub-bands and guard bands.

[Method 9 of the second embodiment]

Method 9 of the second embodiment is a method of defining an interlace index and a set of RBs constituting each interlace in the SB for each LBT-SB.

For example, if the interlace is defined only by RBs belonging to the SB for each LBT-SB of 20 MHz, and a BWP larger than the SB (eg, 40 MHz) is set to the UE, two SBs with individual interlace indexing are applicable. It becomes a form that becomes available to the UE. In addition, the UL transmission resource of the UE is allocated to interlaces included in a plurality of (eg, 2) SBs corresponding to the entire BWP, or included in a specific part (eg, 1) of SBs Can only be assigned to interlaces.

If 30 kHz subcarrier spacing is assumed, a total of 51 RBs exist at 20 MHz, and if the interval between RBs in the interlace is set to N (eg, 5 RB), X interlaces are discontinuous.

(E.g., 11) RBs and NX interlaces are discontinuous

It may be composed of (for example, 10) RBs.

In such a situation, a method for defining a DMRS sequence length in a corresponding UL interlace structure, how to generate it, and how to divide it and map it can be proposed through Method 9 below.

[Method 9-1 of the second embodiment]

In method 9-1 of the second embodiment, a method of setting the DMRS sequence length equal to one RB size (i.e., 12 REs) can be proposed.

The proposed method 7-1 can also be applied to method 9-1.

53 (a) illustrates a method of allocating resources according to method 9-1.

In comparison with method 7-1, in case of FIG. 53 (a) in which resources are allocated according to method 9-1, since the interlace is defined in the SB, the first interlace index of each SB may be 0.

[Method 9-2 of the second embodiment]

In 9-2 of the second embodiment, a method of setting the DMRS sequence length equal to one interlace size in each SB can be proposed.

The proposed method 7-2 can also be applied to method 9-2.

53 (b) illustrates a method of allocating resources according to method 9-2.

Compared to method 7-2, in the case of the example of FIG. 53 (b) in which resources are allocated according to method 9-2, since the interlace is defined in the SB, the first interlace index of each SB may be 0. .

[Method 9-3 of the second embodiment]

In 9-3 of the second embodiment, a method of setting the DMRS sequence length equal to the (multiple) interlace size allocated in each SB can be proposed.

The proposed method 7-3 can also be applied to method 9-3.

53 (c) illustrates a method of allocating resources according to method 9-3.

Compared to method 7-3, in the case of the example of FIG. 53 (c) in which resources are allocated according to method 9-3, since the interlace is defined in the SB, the first interlace index of each SB may be 0. .

[Method 9-4 of the second embodiment]

In 9-4 of the second embodiment, it is possible to propose a method of setting the DMRS sequence length equal to the RB size corresponding to the same interlace index in the allocated SB (group).

The proposed method 7-4 can also be applied to method 9-4.

54 (a) illustrates a method of allocating resources according to methods 9-4.

Compared to method 7-4, in the case of the example of FIG. 54 (a) where resources are allocated according to method 9-4, since the interlace is defined in the SB, the first interlace index of each SB may be 0. .

[Method 9-5 of the second embodiment]

In 9-5 of the second embodiment, it is possible to propose a method of setting the DMRS sequence length equal to the allocated (plural) interlace size in the allocated SB (group).

The proposed method 7-5 can also be applied to method 9-5.

54 (b) illustrates a method of allocating resources according to methods 9-5.

Compared to method 7-5, in the case of the example of FIG. 54 (b) in which resources are allocated according to method 9-5, since the interlace is defined in the SB, the first interlace index of each SB may be 0. .

Similarly, DMRS based on different options may be applied between the proposed methods 9-1 to 9-5b, b different UL channels (for example, PUSCH / PUCCH / SRS). For example, it may be set that the method 9-1 or method 9-2 is applied to PUCCH / SRS, which is a channel based on multiplexing such as CDM / FDM, and method 9-3 is applied to PUSCH. In addition, RRC-configurable operation among the plurality of options or dynamic switching operation (between long vs. short sequences) may be supported through DCI.

When DMRS is generated according to the proposed method, the following DMRS randomization method may be required to reduce inter-cell interference.

[Method 10-1 of the second embodiment]

In method 10-1 of the second embodiment, a method of applying DMRS sequence hopping (eg, root / cyclic shift, scrambling ID / seed) based on the RB index in the entire CC bandwidth is proposed.

[Method 10-2 of the second embodiment]

In method 10-2 of the second embodiment, a method of applying DMRS sequence hopping based on RB index (and / or SB index) in SB is proposed.

[Method 10-3 of the second embodiment]

In method 10-3 of the second embodiment, a method of applying DMRS sequence hopping based on interlace index (and / or SB index) in SB is proposed.

Here, when a single sequence is mapped across multiple RBs, the UE may apply DMRS sequence hopping based on the lowest RB index (and / or lowest sub-band index) to which the corresponding sequence is mapped.

Additionally, in a situation in which an interlace is defined in a sub-band, when the base station indicates an interlace index in common to a plurality of SBs, the UE can be configured such that PRBs in an interlace spanning multiple SBs are not spaced apart. . For example, even if the interlaces are configured with N PRB intervals inside the sub-band index # 0 and the sub-band index # 1, the interlace index indicated by the base station allocated to the sub-band index # 0 is configured. The interval between the last PRB and the first PRB constituting the interlace index indicated by the base station allocated to sub-band index # 1 may not be N.

As shown in FIG. 54 (C), as an example of the above problem, in a situation in which the initially set interlace interval is 5PRB, the interval between sub-bands is 4PRB smaller than the previously set interlace interval.

Meanwhile, in a situation in which resources are allocated as shown in FIG. 54 (C), if the interlace index # 0 of sub-band # 0 and the interlace index # 0 of sub-band # 1 are allocated for transmission of the same UL resource, the interlace is configured. The problem is that the interval between PRBs is not constant. On the other hand, in order to solve this, the base station may indicate the interlace index # 0 in sub-band # 0 and the interlace index # 1 in sub-band # 1, respectively, but the signaling overhead of the base station increases. There are disadvantages.

Therefore, the following methods can be considered to solve this problem. If the base station instructs the interlace index only for the SB having the lowest index among the plurality of SBs, the UE determines that the indicated interlace index is assigned to the UE in the lowest index SB, and corresponds to the remaining SBs except the lowest index SB. It can be set that it is determined that the interlace index corresponding to the PRB set equally spaced with the interlace indicated in the lowest index SB is allocated to the terminal.

That is, in FIG. 54 (c), the base station indicates only interlace index # 0 of sub-band # 0 for a specific UL DATA, and sub which is an interlace index of equal interval with interlace index # 0 of the corresponding sub-band # 0. It can be determined that the interlace index # 1 of -band # 1 is assigned to the terminal. Afterwards, the same method can be applied even if there is more SB. When set in this way, when a terminal transmits UL DATA, it can always maintain an equal interval even in different sub-bands, and has the advantage of lowering PAPR compared to non-uniform transmission from the terminal side.

Additionally, even when the proposed uniform-distance interlace structure is used, all options for generating / mapping the DMRS sequence can be applied.

The proposed "sequence hopping or sequence randomization by SB in CC / BWP" method is applied not only to UL RS (eg, DMRS, etc.) but also DL RS (eg, PDCCH / PDSCH DM-RS, CSI-RS, etc.). can do.

Next, the unified solution for CFS and CBS PUR will be described by taking an NB-IoT system as an example, but the contents to be described later can be applied to the aforementioned NR-U (or U-Band) system as well. .

For example, contents described below may be defined for transmission and reception of signals in an L-cell and / or a U-cell.

[Third Example]

In the third embodiment, the base station indicates a specific time / frequency resource to the UE, and the DMRS and scrambling sequence required for (N) PUSCH transmission on the corresponding T / F resource are SIB (cell or CE level specific) or UE specific RRC. It is proposed to set it as signaling.

The base station is a combination of K (for example, K is a positive integer greater than or equal to 2) orthogonal DMRS and a scrambling sequence for two or more UEs sharing a specific T / F resource (for example, DMRS and scrambling) Combination consisting of sequences (e.g., RNTI values), characteristically, DMRS and scrambling sequences can be set differently between orthogonal combinations, and even if only one of the DMRS or scrambling sequences is different, it can be considered as an orthogonal resource) It can be set to be configured in advance.

At this time, if it can be determined that the base station can allocate the corresponding T / F resource to a number of terminals less than K at a specific time, the base station has a plurality (for example, fewer than K) sharing the corresponding T / F resource. ) May indicate different orthogonal DMRS and scrambling sequences (ie, RNTI values) to UEs of UE) through UE-specific RRC signaling. The UE performs PUR transmission using the DMRS and scrambling sequence indicated by the base station on the corresponding T / F resource based on the value indicated by the base station. As described above, if the base station sets, as a result, it is possible to perform non-competitive operation (i.e., CFS PUR operation).

Since the number of UEs to be allocated to a specific time / frequency (T / F) resource is less than the number of combinations consisting of orthogonal DMRSs and scrambling sequences initially prepared, the base station is configured to perform non-competitive PUR operation by allocating one UE for each group Can be. At this time, the DMRS and scrambling sequence corresponding to the group to which the UE is not allocated may not be used when transmitting PUR to the corresponding T / F resource. In addition, in this case, since the base station can distinguish all N terminals, it is not necessary to require the terminal to transmit additional UE-specific information.

On the other hand, if it can be determined that the base station needs to allocate the corresponding T / F resource to more UEs than K at a specific time, the base station may have a plurality (for example, more than K) sharing the corresponding T / F resource. ), The UEs are classified into K groups so as not to overlap, and a combination of K orthogonal DMRSs and scrambling sequences previously configured to K different UE groups may be indicated by UE-specific RRC signaling.

Here, UEs belonging to the same UE group may be instructed to have the same DMRS and scrambling sequence even though they are transmitted through UE-specific RRC signaling. In addition, it may be set to transmit the corresponding information through UE group signaling rather than UE-specific RRC signaling.

Thereafter, the base station transmits (N) PUSCH when the UE transmits UE-specific preset UE ID information to a plurality of UEs (ie, a plurality of UEs belonging to the same UE group) instructed to use the same DMRS and scrambling sequence. It can be set to instruct to transmit together. At this time, the base station may be configured to transmit a 1-bit field instructing to transmit UE-specific ID information when transmitting (N) PUSCH when instructing DMRS, scrambling sequence, or the like.

Here, the UE ID information can be set that the base station transmits to each terminal when instructed to set the PUR, and when the terminal is switched from the connected mode to the idle mode or from the EDT procedure to the idle mode, or from the base station through the paging procedure. You can also set it to receive. Further, as another example, the UE ID information may be a unique ID of the terminal.

As described above, when the base station allocates resources to the UE, K different UE groups use non-orthogonal DMRS and scrambling sequences to perform non-competitive transmission, but between terminals using the same DMRS and scrambling sequences ( ie, terminals belonging to the same group) contention occurs, and the base station needs to decode the UE's unique ID transmitted by the corresponding terminal and transmit feedback information including which (N) PUSCH of the terminal is received to the terminal. .

Upon receiving the feedback information, the UE can determine whether or not the (N) PUSCH transmission transmitted by itself is properly received. If the contention fails, it can be set to transmit to the existing PUR T / F resource. It can be set to perform an RACH procedure or an EDT procedure.

Since the number of UEs to be allocated to a specific T / F resource is greater than the number of combinations consisting of orthogonal DMRSs and scrambling sequences initially prepared, at least one UE is allocated to each group and K is set in order to set as little competition as possible. UEs exceeding the number may be additionally allocated to a group to which the UE is already allocated according to the determination of the base station.

Here, it may be desirable to set the number of UEs allocated to each group to be the same or differ by at most one in order to achieve the best performance of the CBS PUR operation.

According to FIG. 56, M-6 UEs out of a total of M (= K + 3) UEs perform non-competitive PUR operation, and UEs # 1 and # K + corresponding to groups # 1, # 2, and # 3 1, and UE # 2 and # K + 2, and UE # 3 and # K + 3 perform the contention-based PUR operation, respectively.

Here, since the orthogonality of the DMRS or scrambling sequence is maintained between UEs having different group numbers, it can be determined that no competition occurs. However, since competition occurs within a group containing two or more UEs, the UEs can perform a contention-based PUR operation.

In addition, as another example, the base station needs to request to transmit additional UE-specific information to UEs having a contention-based PUR operation.

On the other hand, the base station may determine and allocate according to the priority of the UL data that the UE intends to send. In the case of a UE having a higher priority, in order to prevent contention, the UE occupies one UE group (ie, orthogonal DMRS And a scrambling sequence to be used by the corresponding UE alone). In the case of a terminal having a low priority, a plurality of terminals may be configured as a group to perform competition between the terminals.

Here, the priority of UL data of the corresponding PUR that the UE intends to transmit may be set to report to the base station when reporting capability of the UE.

As shown in FIG. 57, similar to FIG. 55, after the base station configures a combination of K orthogonal DMRSs and scrambling sequences, M UEs are assigned to specific T / F resources (eg, M = K + 3, M> K).

Since the number of UEs to be allocated to a specific T / F resource is greater than the number of combinations of orthogonal DMRSs and scrambling sequences initially prepared, two or more UEs must be allocated to a specific group.

That is, in FIG. 57, a total of four UEs are allocated to group # 1, and one UE is allocated from group # 2 to group #K. That is, it may correspond to a case where the priority of UL data transmitted by UEs belonging to group # 1 is lower than the priority of UL data transmitted by UEs belonging to groups # 2 to #K.

That is, the contention-based shared PUR operation is performed between the terminals belonging to the group # 1, and the UEs surviving the group # 1 and UEs belonging to other groups perform the non-competitive shared PUR operation. In addition, to the UEs corresponding to group # 1 (i.e., to UEs with contention-based PUR operation), the base station needs to request to transmit additional UE-specific information.

That is, in the proposed method, the same T / F resource may operate as a CFS PUR or a CBS PUR through a 1-bit field indicated by the base station.

In addition, the above-described CBS PUR operation has an advantage that collision probability is very low compared to a contention-based transmission in which all UEs select by random selection using the same probability among resources included in the DMRS pool and the scrambling sequence pool. In addition, in the case of UE, when the (N) PUSCH is transmitted, when the 1-bit field indicating to embedding the UE ID information indicates 0 (for example, indicating that there is no need to transmit the UE ID information), the corresponding PUR setting is non-competitive. It can be seen that the transmission, (N) PUSCH transmission when 1bit field indicating to transmit the UE ID information indicates 1 (for example, indicating that the UE ID information should be transmitted), the corresponding PUR setting is contention-based transmission You can see that

Therefore, when the UE performs CFS PUR transmission, it is possible to expect ACK or NACK through feedback information, and when performing CBS PUR transmission, the base station determines whether the PUR transmitted by the UE is competitive / failure through feedback information. It can be set to expect to deliver this, and additional ACK or NACK information can also be expected.

Additionally, when performing CBS PUR operation, a field indicating that the base station embedding UE ID information when transmitting (N) PUSCH is transmitted may indicate as "ON", and the base station may transmit (UE specific UE ID information with UL data). If the decoding of the UL data is NACK in the state where the UE ID is recognized (assuming that it is separated encoding), instructing retransmission to (N) PDCCH based on RNTI (for example, UE-specific C-RNTI) corresponding to the UE ID. Can be set.

In addition, in the case of CFS PUR operation, when a base station transmits (N) PUSCH, a field instructing to embedding UE ID information and transmitting it may indicate "OFF", and if decoding of UL data is NACK, simply Although it may be set to indicate retransmission to (N) PDCCH based on UE-specific C-RNTI using the corresponding DMRS, retransmission is indicated through (N) PDCCH specific to the corresponding CFS PUR resource (e.g., DMRS, scrambling sequence). You can also set it. For example, in RNTI-based (N) PDCCH corresponding to T / F resources for CFS PUR (not C-RNTI), ACK / NACK information is mapped for each DMRS (or combined with a scrambling sequence in DMRS). / Transmit, the UE can perform the retransmission operation by reading the ACK / NACK information corresponding to the DMRS they used. In this configuration, there is an advantage in that retransmission DCI overhead can be reduced compared to transmission of ACK / NACK information by using (N) PDCCH based on C-RNTI for each UE.

If the proposed method is a method in which the base station determines whether to perform CFS PUR operation or CBS PUR operation for a specific terminal at a specific time, unlike this, the first base station instructs CFS PUR operation to a specific terminal and then CBS PUR The above proposed method can be applied to a situation instructing to operate, or a situation in which the first base station instructs a specific terminal to perform CBS PUR operation and then instructs to perform CFS PUR operation.

Specifically, it is as follows.

If the base station provides K orthogonal resources (e.g., DMRS, scrambling sequence, etc.) to perform CFS PUR operation on a specific T / F resource, UE-specific RRC signaling of the corresponding information to UEs requesting PUR After instructing (in this case, it is preferable that the field instructing to embedding and transmit UE ID information when transmitting (N) PUSCH is set to "OFF"). If you try to assign to, similar to the above-mentioned method, a situation may arise in which the orthogonal resource that has already been assigned to a specific UE must be used for another UE.

In this case, UEs to be newly allocated may be configured to indicate that a field indicating that the base station embedding and transmits UE ID information when transmitting (N) PUSCH through UE-specific RRC signaling is set to “ON”, and the base station can be configured to A field instructing UEs assigned to perform CFS PUR operation to embedding and transmit UE ID information when (N) PUSCH is transmitted through a specific channel / signal that can be received even in idle mode, such as an ACK / NACK feedback channel. It can be said that it is indicated by setting "ON".

That is, the UE initially received an operation received from the base station through UE-specific RRC signaling was a CFS PUR operation, but the base station instructed to perform the CBS PUR operation through a path such as an ACK / NACK feedback channel. Through a similar method, the base station may instruct the UE that was performing the initial CBS PUR operation to perform the CFS PUR operation.

In addition, when the base station gives the UE specific RRC signaling, the following scheme may be considered. The first base station can indicate the number of orthogonal resources (for example, DMRS, scrambling sequence, etc.) set that can be used for CFS PUR operation on the same T / F resource to the UE (K value in the above example), in addition The base station may inform the user of the number of orthogonal resources corresponding to the K orthogonal resource set for the CFS PUR operation.

Thereafter, the terminal can be set to find out the actual DMRS and the scrambling sequence index according to the result of the previously promised method or equation.

In addition, when group ACK / NACK is supported, when a corresponding orthogonal resource is used, the base station may indicate to the UE whether the ACK / NACK of the UE exists at a position of the group ACK / NACK. The advantage of this setting method is that RRC signaling overhead can be reduced compared to instructing each terminal to a specific DMRS and scrambling sequence index.

In addition, after indicating the number of orthogonal resources (for example, DMRS, scrambling sequence, etc.) set that can be used for the CFS PUR operation (K value in the example above), a value greater than the corresponding K value is given to the actual terminal. (For example, L) When instructed, the UE orthogonally selects an orthogonal resource for a value corresponding to K '= L mod K, K' according to a predetermined method or a result of a mathematical expression. The resource may be selected, and the corresponding UE may be configured to determine that it is a CBS PUR operation and transmit (N) PUSCH embedded with a UE specific ID. That is, the base station instructs the UE to perform the CBS PUR operation implicitly by indicating a value greater than the number of orthogonal resource sets that can be used for the CFS PUR operation, and the UE ID information when transmitting the aforementioned (N) PUSCH The advantage is that you do not have to use a field that instructs to embedding and transmit.

In addition, the following methods can be considered in relation to ACK / NACK feedback of CBS PUR. When a UE performing CBS PUR operation receives an ACK, two cases may exist. (1) When a corresponding UE ID is ACK for a resource transmitted by the UE, and (2) for a resource transmitted by the UE. There may be a case where a UE ID other than the corresponding UE ID is ACK. If, as in (2), the other UE ID is ACK for the resource transmitted by the corresponding UE, (A) wait until the next CBS PUR transmission time and retransmit the method, (B) EDT procedure or RA procedure You can also set it to fallback to

That is, when the base station fails to decode the CBS PUR transmission sent by the UE, the number of cases the UE can expect is (1) explicit NACK, or (2) NACK for another UE, or (3) no feedback. In the case of (3), power ramping up may be performed upon retransmission, and in the case of (1) and / or (2), power ramping up may not be allowed. Of course, if there is special signaling for the TPC in (1) and / or (2), this can be followed.

Base station / terminal operation of the present specification

58 is for convenience of description only and does not limit the scope of the present specification.

Referring to FIG. 58, the wireless communication system coexists in the system band of another wireless communication system (eg, NR system), such as the above-described methods (eg, the methods described in the first to third embodiments) (coexist) is assumed. That is, the method described in FIG. 58 may be operated, set, defined and / or directed based on the methods described above.

First, the terminal may receive uplink resource related information including a plurality of interlace units from the base station (S5801).

Subsequently, the terminal may transmit a demodulation reference signal sequence having the same length as the entire length of the plurality of interlaces to the base station through the uplink resource (S5803).

59 is for convenience of description only and does not limit the scope of the present specification.

First, the base station may transmit uplink resource related information including a plurality of interlace units to the terminal (S5901).

Subsequently, the base station may receive a demodulation reference signal sequence having the same length as the entire length of the plurality of interlaces from the terminal through the uplink resource (S5903).

60 is for convenience of description only and does not limit the scope of the present specification.

As shown in FIG. 60, the base station transmits uplink resource related information including a plurality of interlace units to the terminal (S6001).

Subsequently, the terminal transmits a demodulation reference signal sequence having the same length as the entire length of the plurality of interlaces to the base station through the uplink resource (S6003).

The embodiments described above are those in which components and features of the present specification are combined in a predetermined form. Each component or feature should be considered optional unless stated otherwise. Each component or feature may be implemented in a form that is not combined with other components or features. In addition, it is also possible to configure an embodiment of the present specification by combining some components and / or features. The order of the operations described in the embodiments of the present specification may be changed. Some configurations or features of one embodiment may be included in other embodiments, or may be replaced with corresponding configurations or features of other embodiments. It is apparent that claims that do not have an explicit citation relationship in the claims can be combined to form an embodiment or included as a new claim by correction after filing.

Embodiments according to the present specification may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. For implementation by hardware, one embodiment of the present specification is one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), FPGAs ( field programmable gate arrays), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of implementation by firmware or software, an embodiment of the present specification may be implemented in the form of a module, procedure, function, etc. that performs the functions or operations described above. The software code can be stored in memory and driven by a processor. The memory is located inside or outside the processor, and can exchange data with the processor by various known means.

It is apparent to those skilled in the art that the present specification may be embodied in other specific forms without departing from essential features of the present specification. Therefore, the above detailed description should not be construed as limiting in all respects and should be considered illustrative. The scope of the present specification should be determined by rational interpretation of the appended claims, and all changes within the equivalent scope of the present specification are included in the scope of the present specification.

Although this specification is mainly focused on an example applied to the 3GPP LTE / LTE-A / NR system, it can be applied to various wireless communication systems in addition to the 3GPP LTE / LTE-A / NR system.

Claims

In the terminal for transmitting the uplink from the wireless communication system to the base station,

Communication unit for transmitting and receiving wireless signals;

Processor; And

And at least one computer memory operatively connectable to the processor and storing instructions to perform operations when executed by the at least one processor,

The above operations,

Receiving information related to uplink resources from the base station; And

Including; transmitting an uplink to the base station through the uplink resource;

The uplink resource includes a plurality of interlace units,

The step of transmitting the uplink,

A demodulation reference signal (DMRS) sequence having the same length as the entire length of the plurality of interlaces is transmitted.

Terminal.
According to claim 1,

The demodulation reference signal sequence is a form in which a plurality of demodulation reference signals are concatenated.

The number of the plurality of demodulation reference signals is characterized in that the number of a plurality of unit resource element groups included in the plurality of interlaces,

Terminal.
According to claim 2,

The uplink resource includes a plurality of sub-bands to which the plurality of interlace units are mapped,

The plurality of reference signals is characterized in that the connection between the plurality of sub-bands,

Terminal.
According to claim 3,

The demodulation reference signal sequence is characterized in that it comprises a guard band (guard band) between the plurality of sub-bands,

Terminal.
In a base station for receiving an uplink from a terminal in a wireless communication system,

Communication unit for transmitting and receiving wireless signals;

Processor; And

And at least one computer memory operatively connectable to the processor and storing instructions to perform operations when executed by the at least one processor,

The above operations,

Transmitting information related to an uplink resource to the terminal; And

Including; receiving an uplink from the terminal through the uplink resource;

The uplink resource includes a plurality of interlace units,

The step of receiving the uplink,

Characterized in that it receives a demodulation reference signal (DMRS) sequence of the same length as the total length of the plurality of interlaces,

Base station.
The method of claim 5,

The demodulation reference signal sequence is a form in which a plurality of demodulation reference signals are concatenated.

The number of the plurality of demodulation reference signals is characterized in that the number of a plurality of unit resource element groups included in the plurality of interlaces,

Base station.
The method of claim 6,

The uplink resource includes a plurality of sub-bands to which the plurality of interlace units are mapped,

The plurality of reference signals is characterized in that the connection between the plurality of sub-bands,

Base station.
The method of claim 7,

The demodulation reference signal sequence is characterized in that it comprises a guard band (guard band) between the plurality of sub-bands,

Base station.