WO2020032532A1

WO2020032532A1 - Method and apparatus for monitoring paging on unlicensed bands in wireless communication system

Info

Publication number: WO2020032532A1
Application number: PCT/KR2019/009781
Authority: WO
Inventors: Yejee LEE; Youngdae Lee
Original assignee: Lg Electronics Inc.
Priority date: 2018-08-09
Filing date: 2019-08-06
Publication date: 2020-02-13

Abstract

A method and apparatus for monitoring paging on unlicensed bands in a wireless communication system is provided. A wireless device calculates a first paging occasion (PO) based on its identifier (ID), receives information on timing of monitoring paging from a network, and monitors the first PO. When a discovery signal is not detected in the first PO, the wireless calculates a second PO based on the information on the timing of monitoring paging, not based on its ID, and monitors the second PO. The second PO is a PO associated with other wireless device, but not associated with the wireless device by the ID of the wireless device.

Description

METHOD AND APPARATUS FOR MONITORING PAGING ON UNLICENSED BANDS IN WIRELESS COMMUNICATION SYSTEM

The present invention relates to wireless communications, and more particularly, to a method and apparatus for monitoring paging on unlicensed bands in a wireless communication system.

3rd generation partnership project (3GPP) long-term evolution (LTE) is a technology for enabling high-speed packet communications. Many schemes have been proposed for the LTE objective including those that aim to reduce user and provider costs, improve service quality, and expand and improve coverage and system capacity. The 3GPP LTE requires reduced cost per bit, increased service availability, flexible use of a frequency band, a simple structure, an open interface, and adequate power consumption of a terminal as an upper-level requirement.

Work has started in international telecommunication union (ITU) and 3GPP to develop requirements and specifications for new radio (NR) systems. 3GPP has to identify and develop the technology components needed for successfully standardizing the new RAT timely satisfying both the urgent market needs, and the more long-term requirements set forth by the ITU radio communication sector (ITU-R) international mobile telecommunications (IMT)-2020 process. Further, the NR should be able to use any spectrum band ranging at least up to 100 GHz that may be made available for wireless communications even in a more distant future.

The NR targets a single technical framework addressing all usage scenarios, requirements and deployment scenarios including enhanced mobile broadband (eMBB), massive machine-type-communications (mMTC), ultra-reliable and low latency communications (URLLC), etc. The NR shall be inherently forward compatible.

Carrier aggregation with at least one secondary cell (SCell) operating in the unlicensed spectrum is referred to as licensed-assisted access (LAA). In LAA, the configured set of serving cells for a UE therefore always includes at least one SCell operating in the unlicensed spectrum according to frame structure Type 3, also called LAA SCell. Unless otherwise specified, LAA SCells act as regular SCells.

LAA eNodeB (eNB) and user equipment (UE) apply listen-before-talk (LBT) before performing a transmission on LAA SCell. When LBT is applied, the transmitter listens to/senses the channel to determine whether the channel is free or busy. If the channel is determined to be free, the transmitter may perform the transmission. Otherwise, it does not perform the transmission. If an LAA eNB uses channel access signals of other technologies for the purpose of LAA channel access, it shall continue to meet the LAA maximum energy detection threshold requirement.

NR standalone operation on unlicensed bands is being discussed. Therefore, a method for supporting NR standalone operation on unlicensed bands efficiently is required. Specifically, since a cell on the unlicensed bands can be configured as a primary cell (PCell) in the NR standalone operation on unlicensed bands, paging should be performed on the unlicensed bands. In this case, LBT failure may impact paging.

In an aspect, a method performed by a wireless device in a wireless communication system is provided. The method includes calculating a first paging occasion (PO) based on an identifier (ID) of the wireless device, receiving information on timing of monitoring paging from a network, monitoring the first PO, when a discovery signal is not detected in the first PO: calculating a second PO based on the information on the timing of monitoring paging, not based on the ID of the wireless device, and monitoring the second PO. The second PO is a PO associated with other wireless device, but not associated with the wireless device by the ID of the wireless device.

In another aspect, a wireless device in a wireless communication system is provided. The wireless device includes a memory, a transceiver, and a processor, operably coupled to the memory and the transceiver, configured to calculate a first paging occasion (PO) based on an identifier (ID) of the wireless device, control the transceiver to receive information on timing of monitoring paging from a network, control the transceiver to monitor the first PO, when a discovery signal is not detected in the first PO: calculate a second PO based on the information on the timing of monitoring paging, not based on the ID of the wireless device, and control the transceiver to monitor the second PO. The second PO is a PO associated with other wireless device, but not associated with the wireless device by the ID of the wireless device.

The UE can quickly receive paging in the additional monitoring window without waiting until the next monitoring window occurs.

FIG. 1 shows examples of 5G usage scenarios to which the technical features of the present invention can be applied.

FIG. 2 shows an example of a wireless communication system to which the technical features of the present invention can be applied.

FIG. 3 shows an example of a wireless communication system to which the technical features of the present invention can be applied.

FIG. 4 shows another example of a wireless communication system to which the technical features of the present invention can be applied.

FIG. 5 shows a block diagram of a user plane protocol stack to which the technical features of the present invention can be applied.

FIG. 6 shows a block diagram of a control plane protocol stack to which the technical features of the present invention can be applied.

FIG. 7 shows an example of a method for monitoring paging on unlicensed bands according to the embodiment 1 of the present invention.

FIG. 8 shows an example of monitoring additional PO based on bitmap information according to the embodiment 1 of the present invention.

FIG. 9 shows another example of monitoring additional PO based on bitmap information according to the embodiment 1 of the present invention.

FIG. 10 shows an example of monitoring PO based on a negative indicator according to the embodiment 1 of the present invention.

FIG. 11 shows another example of monitoring PO based on a negative indicator according to the embodiment 1 of the present invention.

FIG. 12 shows an example of monitoring PO according to the embodiment 2 of the present invention.

FIG. 13 shows a UE to which the technical features of the present invention can be applied.

FIG. 14 shows an example of an AI device to which the technical features of the present invention can be applied.

FIG. 15 shows an example of an AI system to which the technical features of the present invention can be applied.

The technical features described below may be used by a communication standard by the 3rd generation partnership project (3GPP) standardization organization, a communication standard by the institute of electrical and electronics engineers (IEEE), etc. For example, the communication standards by the 3GPP standardization organization include long-term evolution (LTE) and/or evolution of LTE systems. The evolution of LTE systems includes LTE-advanced (LTE-A), LTE-A Pro, and/or 5G new radio (NR). The communication standard by the IEEE standardization organization includes a wireless local area network (WLAN) system such as IEEE 802.11a/b/g/n/ac/ax. The above system uses various multiple access technologies such as orthogonal frequency division multiple access (OFDMA) and/or single carrier frequency division multiple access (SC-FDMA) for downlink (DL) and/or uplink (UL). For example, only OFDMA may be used for DL and only SC-FDMA may be used for UL. Alternatively, OFDMA and SC-FDMA may be used for DL and/or UL.

In this document, the term "/" and "," should be interpreted to indicate "and/or." For instance, the expression "A/B" may mean "A and/or B." Further, "A, B" may mean "A and/or B." Further, "A/B/C" may mean "at least one of A, B, and/or C." Also, "A, B, C" may mean "at least one of A, B, and/or C."

Further, in the document, the term "or" should be interpreted to indicate "and/or." For instance, the expression "A or B" may comprise 1) only A, 2) only B, and/or 3) both A and B. In other words, the term "or" in this document should be interpreted to indicate "additionally or alternatively."

The 5G usage scenarios shown in FIG. 1 are only exemplary, and the technical features of the present invention can be applied to other 5G usage scenarios which are not shown in FIG. 1.

Referring to FIG. 1, the three main requirements areas of 5G include (1) enhanced mobile broadband (eMBB) domain, (2) massive machine type communication (mMTC) area, and (3) ultra-reliable and low latency communications (URLLC) area. Some use cases may require multiple areas for optimization and, other use cases may only focus on only one key performance indicator (KPI). 5G is to support these various use cases in a flexible and reliable way.

eMBB focuses on across-the-board enhancements to the data rate, latency, user density, capacity and coverage of mobile broadband access. The eMBB aims ~10 Gbps of throughput. eMBB far surpasses basic mobile Internet access and covers rich interactive work and media and entertainment applications in cloud and/or augmented reality. Data is one of the key drivers of 5G and may not be able to see dedicated voice services for the first time in the 5G era. In 5G, the voice is expected to be processed as an application simply using the data connection provided by the communication system. The main reason for the increased volume of traffic is an increase in the size of the content and an increase in the number of applications requiring high data rates. Streaming services (audio and video), interactive video and mobile Internet connectivity will become more common as more devices connect to the Internet. Many of these applications require always-on connectivity to push real-time information and notifications to the user. Cloud storage and applications are growing rapidly in mobile communication platforms, which can be applied to both work and entertainment. Cloud storage is a special use case that drives growth of uplink data rate. 5G is also used for remote tasks on the cloud and requires much lower end-to-end delay to maintain a good user experience when the tactile interface is used. In entertainment, for example, cloud games and video streaming are another key factor that increases the demand for mobile broadband capabilities. Entertainment is essential in 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 latency and instantaneous data amount.

mMTC is designed to enable communication between devices that are low-cost, massive in number and battery-driven, intended to support applications such as smart metering, logistics, and field and body sensors. mMTC aims ~10 years on battery and/or ~1 million devices/km2. mMTC allows seamless integration of embedded sensors in all areas and is one of the most widely used 5G applications. Potentially by 2020, internet-of-things (IoT) devices are expected to reach 20.4 billion. Industrial IoT is one of the areas where 5G plays a key role in enabling smart cities, asset tracking, smart utilities, agriculture and security infrastructures.

URLLC will make it possible for devices and machines to communicate with ultra-reliability, very low latency and high availability, making it ideal for vehicular communication, industrial control, factory automation, remote surgery, smart grids and public safety applications.　URLLC aims ~1ms of latency. URLLC includes new services that will change the industry through links with ultra-reliability / low latency, such as remote control of key infrastructure and self-driving vehicles. The level of reliability and latency is essential for smart grid control, industrial automation, robotics, drones control and coordination.

Next, a plurality of use cases included in the triangle of FIG. 1 will be described in more detail.

5G can complement fiber-to-the-home (FTTH) and cable-based broadband (or DOCSIS) as a means of delivering streams rated from hundreds of megabits per second to gigabits per second. This high speed can be required to deliver TVs with resolutions of 4K or more (6K, 8K and above) as well as virtual reality (VR) and augmented reality (AR). VR and AR applications include mostly immersive sporting events. Certain applications may require special network settings. For example, in the case of a VR game, a game company may need to integrate a core server with an edge network server of a network operator to minimize delay.

Automotive is expected to become an important new driver for 5G, with many use cases for mobile communications to vehicles. For example, entertainment for passengers demands high capacity and high mobile broadband at the same time. This is because future users will continue to expect high-quality connections regardless of their location and speed. Another use case in the automotive sector is an augmented reality dashboard. The driver can identify an object in the dark on top of what is being viewed through the front window through the augmented reality dashboard. The augmented reality dashboard displays information that will inform the driver about the object's distance and movement. In the future, the wireless module enables communication between vehicles, information exchange between the vehicle and the supporting infrastructure, and information exchange between the vehicle and other connected devices (e.g. devices accompanied by a pedestrian). The safety system allows the driver to guide the alternative course of action so that he can drive more safely, thereby reducing the risk of accidents. The next step will be a remotely controlled vehicle or self-driving vehicle. This requires a very reliable and very fast communication between different self-driving vehicles and between vehicles and infrastructure. In the future, a self-driving vehicle will perform all driving activities, and the driver will focus only on traffic that the vehicle itself cannot identify. The technical requirements of self-driving vehicles require ultra-low latency and high-speed reliability to increase traffic safety to a level not achievable by humans.

Smart cities and smart homes, which are referred to as smart societies, will be embedded in high density wireless sensor networks. The distributed network of intelligent sensors will identify conditions for cost and energy-efficient maintenance of a city or house. A similar setting can be performed for each home. Temperature sensors, windows and heating controllers, burglar alarms and appliances are all wirelessly connected. Many of these sensors typically require low data rate, low power and low cost. However, for example, real-time high-definition (HD) video may be required for certain types of devices for monitoring.

The consumption and distribution of energy, including heat or gas, is highly dispersed, requiring automated control of distributed sensor networks. The smart grid interconnects these sensors using digital information and communication technologies to collect and act on information. This information can include supplier and consumer behavior, allowing the smart grid to improve the distribution of fuel, such as electricity, in terms of efficiency, reliability, economy, production sustainability, and automated methods. 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. Communication systems can support telemedicine to provide clinical care in remote locations. This can help to reduce barriers to distance and improve access to health services that are not continuously available in distant rural areas. It is also used to save lives in critical care and emergency situations. Mobile communication based wireless sensor networks 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 costs are high for installation and maintenance. Thus, the possibility of replacing a cable with a wireless link that can be reconfigured is an attractive opportunity in many industries. However, achieving this requires that wireless connections operate with similar delay, reliability, and capacity as cables and that their management is simplified. Low latency and very low error probabilities are new requirements that need to be connected to 5G.

Logistics and freight tracking are important use cases of mobile communications that enable tracking of inventory and packages anywhere using location based information systems. Use cases of logistics and freight tracking typically require low data rates, but require a large range and reliable location information.

Referring to FIG. 2, the wireless communication system may include a first device 210 and a second device 220.

The first device 210 includes a base station, a network node, a transmitting UE, a receiving UE, a wireless device, a wireless communication device, a vehicle, a vehicle equipped with an autonomous driving function, a connected car, a drone, an unmanned aerial vehicle (UAV), an artificial intelligence (AI) module, a robot, an AR device, a VR device, a mixed reality (MR) device, a hologram device, a public safety device, an MTC device, an IoT device, a medical device, a fin-tech device (or, a financial device), a security device, a climate/environmental device, a device related to 5G services, or a device related to the fourth industrial revolution.

The second device 220 includes a base station, a network node, a transmitting UE, a receiving UE, a wireless device, a wireless communication device, a vehicle, a vehicle equipped with an autonomous driving function, a connected car, a drone, a UAV, an AI module, a robot, an AR device, a VR device, an MR device, a hologram device, a public safety device, an MTC device, an IoT device, a medical device, a fin-tech device (or, a financial device), a security device, a climate/environmental device, a device related to 5G services, or a device related to the fourth industrial revolution.

For example, the UE may include a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a slate personal computer (PC), a tablet PC, an ultrabook, a wearable device (e.g. a smartwatch, a smart glass, a head mounted display (HMD)) . For example, the HMD may be a display device worn on the head. For example, the HMD may be used to implement AR, VR and/or MR.

For example, the drone may be a flying object that is flying by a radio control signal without a person boarding it. For example, the VR device may include a device that implements an object or background in the virtual world. For example, the AR device may include a device that implements connection of an object and/or a background of a virtual world to an object and/or a background of the real world. For example, the MR device may include a device that implements fusion of an object and/or a background of a virtual world to an object and/or a background of the real world. For example, the hologram device may include a device that implements a 360-degree stereoscopic image by recording and playing stereoscopic information by utilizing a phenomenon of interference of light generated by the two laser lights meeting with each other, called holography. For example, the public safety device may include a video relay device or a video device that can be worn by the user's body. For example, the MTC device and the IoT device may be a device that do not require direct human intervention or manipulation. For example, the MTC device and the IoT device may include a smart meter, a vending machine, a thermometer, a smart bulb, a door lock and/or various sensors. For example, the medical device may be a device used for the purpose of diagnosing, treating, alleviating, handling, or preventing a disease. For example, the medical device may be a device used for the purpose of diagnosing, treating, alleviating, or correcting an injury or disorder. For example, the medical device may be a device used for the purpose of inspecting, replacing or modifying a structure or function. For example, the medical device may be a device used for the purpose of controlling pregnancy. For example, the medical device may include a treatment device, a surgical device, an (in vitro) diagnostic device, a hearing aid and/or a procedural device, etc. For example, a security device may be a device installed to prevent the risk that may occur and to maintain safety. For example, the security device may include a camera, a closed-circuit TV (CCTV), a recorder, or a black box. For example, the fin-tech device may be a device capable of providing financial services such as mobile payment. For example, the fin-tech device may include a payment device or a point of sales (POS). For example, the climate/environmental device may include a device for monitoring or predicting the climate/environment.

The first device 210 may include at least one or more processors, such as a processor 211, at least one memory, such as a memory 212, and at least one transceiver, such as a transceiver 213. The processor 211 may perform the functions, procedures, and/or methods of the present invention described below. The processor 211 may perform one or more protocols. For example, the processor 211 may perform one or more layers of the air interface protocol. The memory 212 is connected to the processor 211 and may store various types of information and/or instructions. The transceiver 213 is connected to the processor 211 and may be controlled to transmit and receive wireless signals.

The second device 220 may include at least one or more processors, such as a processor 221, at least one memory, such as a memory 222, and at least one transceiver, such as a transceiver 223. The processor 221 may perform the functions, procedures, and/or methods of the present invention described below. The processor 221 may perform one or more protocols. For example, the processor 221 may perform one or more layers of the air interface protocol. The memory 222 is connected to the processor 221 and may store various types of information and/or instructions. The transceiver 223 is connected to the processor 221 and may be controlled to transmit and receive wireless signals.

The

memory

212, 222 may be connected internally or externally to the

processor

211, 212, or may be connected to other processors via a variety of technologies such as wired or wireless connections.

The first device 210 and/or the second device 220 may have more than one antenna. For example, antenna 214 and/or antenna 224 may be configured to transmit and receive wireless signals.

Specifically, FIG. 3 shows a system architecture based on an evolved-UMTS terrestrial radio access network (E-UTRAN). The aforementioned LTE is a part of an evolved-UTMS (e-UMTS) using the E-UTRAN.

Referring to FIG. 3, the wireless communication system includes one or more user equipment (UE) 310, an E-UTRAN and an evolved packet core (EPC). The UE 310 refers to a communication equipment carried by a user. The UE 310 may be fixed or mobile. The UE 310 may be referred to as another terminology, such as a mobile station (MS), a user terminal (UT), a subscriber station (SS), a wireless device, etc.

The E-UTRAN consists of one or more evolved NodeB (eNB) 320. The eNB 320 provides the E-UTRA user plane and control plane protocol terminations towards the UE 10. The eNB 320 is generally a fixed station that communicates with the UE 310. The eNB 320 hosts the functions, such as inter-cell radio resource management (RRM), radio bearer (RB) control, connection mobility control, radio admission control, measurement configuration/provision, dynamic resource allocation (scheduler), etc. The eNB 320 may be referred to as another terminology, such as a base station (BS), a base transceiver system (BTS), an access point (AP), etc.

A downlink (DL) denotes communication from the eNB 320 to the UE 310. An uplink (UL) denotes communication from the UE 310 to the eNB 320. A sidelink (SL) denotes communication between the UEs 310. In the DL, a transmitter may be a part of the eNB 320, and a receiver may be a part of the UE 310. In the UL, the transmitter may be a part of the UE 310, and the receiver may be a part of the eNB 320. In the SL, the transmitter and receiver may be a part of the UE 310.

The EPC includes a mobility management entity (MME), a serving gateway (S-GW) and a packet data network (PDN) gateway (P-GW). The MME hosts the functions, such as non-access stratum (NAS) security, idle state mobility handling, evolved packet system (EPS) bearer control, etc. The S-GW hosts the functions, such as mobility anchoring, etc. The S-GW is a gateway having an E-UTRAN as an endpoint. For convenience, MME/S-GW 330 will be referred to herein simply as a "gateway," but it is understood that this entity includes both the MME and S-GW. The P-GW hosts the functions, such as UE Internet protocol (IP) address allocation, packet filtering, etc. The P-GW is a gateway having a PDN as an endpoint. The P-GW is connected to an external network.

The UE 310 is connected to the eNB 320 by means of the Uu interface. The UEs 310 are interconnected with each other by means of the PC5 interface. The eNBs 320 are interconnected with each other by means of the X2 interface. The eNBs 320 are also connected by means of the S1 interface to the EPC, more specifically to the MME by means of the S1-MME interface and to the S-GW by means of the S1-U interface. The S1 interface supports a many-to-many relation between MMEs / S-GWs and eNBs.

Specifically, FIG. 4 shows a system architecture based on a 5G NR. The entity used in the 5G NR (hereinafter, simply referred to as "NR") may absorb some or all of the functions of the entities introduced in FIG. 3 (e.g. eNB, MME, S-GW). The entity used in the NR may be identified by the name "NG" for distinction from the LTE/LTE-A.

Referring to FIG. 4, the wireless communication system includes one or more UE 410, a next-generation RAN (NG-RAN) and a 5th generation core network (5GC). The NG-RAN consists of at least one NG-RAN node. The NG-RAN node is an entity corresponding to the eNB 320 shown in FIG. 3. The NG-RAN node consists of at least one gNB 421 and/or at least one ng-eNB 422. The gNB 421 provides NR user plane and control plane protocol terminations towards the UE 410. The ng-eNB 422 provides E-UTRA user plane and control plane protocol terminations towards the UE 410.

The 5GC includes an access and mobility management function (AMF), a user plane function (UPF) and a session management function (SMF). The AMF hosts the functions, such as NAS security, idle state mobility handling, etc. The AMF is an entity including the functions of the conventional MME. The UPF hosts the functions, such as mobility anchoring, protocol data unit (PDU) handling. The UPF an entity including the functions of the conventional S-GW. The SMF hosts the functions, such as UE IP address allocation, PDU session control.

The gNBs 421 and ng-eNBs 422 are interconnected with each other by means of the Xn interface. The gNBs 421 and ng-eNBs 422 are also connected by means of the NG interfaces to the 5GC, more specifically to the AMF by means of the NG-C interface and to the UPF by means of the NG-U interface.

A protocol structure between network entities described above is described. On the system of FIG. 3 and/or FIG. 4, layers of a radio interface protocol between the UE and the network (e.g. NG-RAN and/or E-UTRAN) may be classified into a first layer (L1), a second layer (L2), and a third layer (L3) based on the lower three layers of the open system interconnection (OSI) model that is well-known in the communication system.

FIG. 5 shows a block diagram of a user plane protocol stack to which the technical features of the present invention can be applied. FIG. 6 shows a block diagram of a control plane protocol stack to which the technical features of the present invention can be applied.

The user/control plane protocol stacks shown in FIG. 5 and FIG. 6 are used in NR. However, user/control plane protocol stacks shown in FIG. 5 and FIG. 6 may be used in LTE/LTE-A without loss of generality, by replacing gNB/AMF with eNB/MME.

Referring to FIG. 5 and FIG. 6, a physical (PHY) layer belonging to L1. The PHY layer offers information transfer services to media access control (MAC) sublayer and higher layers. The PHY layer offers to the MAC sublayer transport channels. Data between the MAC sublayer and the PHY layer is transferred via the transport channels. Between different PHY layers, i.e., between a PHY layer of a transmission side and a PHY layer of a reception side, data is transferred via the physical channels.

The MAC sublayer belongs to L2. The main services and functions of the MAC sublayer include mapping between logical channels and transport channels, multiplexing/de-multiplexing of MAC service data units (SDUs) belonging to one or different logical channels into/from transport blocks (TB) delivered to/from the physical layer on transport channels, scheduling information reporting, error correction through hybrid automatic repeat request (HARQ), priority handling between UEs by means of dynamic scheduling, priority handling between logical channels of one UE by means of logical channel prioritization (LCP), etc. The MAC sublayer offers to the radio link control (RLC) sublayer logical channels.

The RLC sublayer belong to L2. The RLC sublayer supports three transmission modes, i.e. transparent mode (TM), unacknowledged mode (UM), and acknowledged mode (AM), in order to guarantee various quality of services (QoS) required by radio bearers. The main services and functions of the RLC sublayer depend on the transmission mode. For example, the RLC sublayer provides transfer of upper layer PDUs for all three modes, but provides error correction through ARQ for AM only. In LTE/LTE-A, the RLC sublayer provides concatenation, segmentation and reassembly of RLC SDUs (only for UM and AM data transfer) and re-segmentation of RLC data PDUs (only for AM data transfer). In NR, the RLC sublayer provides segmentation (only for AM and UM) and re-segmentation (only for AM) of RLC SDUs and reassembly of SDU (only for AM and UM). That is, the NR does not support concatenation of RLC SDUs. The RLC sublayer offers to the packet data convergence protocol (PDCP) sublayer RLC channels.

The PDCP sublayer belong to L2. The main services and functions of the PDCP sublayer for the user plane include header compression and decompression, transfer of user data, duplicate detection, PDCP PDU routing, retransmission of PDCP SDUs, ciphering and deciphering, etc. The main services and functions of the PDCP sublayer for the control plane include ciphering and integrity protection, transfer of control plane data, etc.

The service data adaptation protocol (SDAP) sublayer belong to L2. The SDAP sublayer is only defined in the user plane. The SDAP sublayer is only defined for NR. The main services and functions of SDAP include, mapping between a QoS flow and a data radio bearer (DRB), and marking QoS flow ID (QFI) in both DL and UL packets. The SDAP sublayer offers to 5GC QoS flows.

A radio resource control (RRC) layer belongs to L3. The RRC layer is only defined in the control plane. The RRC layer controls radio resources between the UE and the network. To this end, the RRC layer exchanges RRC messages between the UE and the BS. The main services and functions of the RRC layer include broadcast of system information related to AS and NAS, paging, establishment, maintenance and release of an RRC connection between the UE and the network, security functions including key management, establishment, configuration, maintenance and release of radio bearers, mobility functions, QoS management functions, UE measurement reporting and control of the reporting, NAS message transfer to/from NAS from/to UE.

In other words, the RRC layer controls logical channels, transport channels, and physical channels in relation to the configuration, reconfiguration, and release of radio bearers. A radio bearer refers to a logical path provided by L1 (PHY layer) and L2 (MAC/RLC/PDCP/SDAP sublayer) for data transmission between a UE and a network. Setting the radio bearer means defining the characteristics of the radio protocol layer and the channel for providing a specific service, and setting each specific parameter and operation method. Radio bearer may be divided into signaling RB (SRB) and data RB (DRB). The SRB is used as a path for transmitting RRC messages in the control plane, and the DRB is used as a path for transmitting user data in the user plane.

An RRC state indicates whether an RRC layer of the UE is logically connected to an RRC layer of the E-UTRAN. In LTE/LTE-A, when the RRC connection is established between the RRC layer of the UE and the RRC layer of the E-UTRAN, the UE is in the RRC connected state (RRC_CONNECTED). Otherwise, the UE is in the RRC idle state (RRC_IDLE). In NR, the RRC inactive state (RRC_INACTIVE) is additionally introduced. RRC_INACTIVE may be used for various purposes. For example, the massive machine type communications (MMTC) UEs can be efficiently managed in RRC_INACTIVE. When a specific condition is satisfied, transition is made from one of the above three states to the other.

A predetermined operation may be performed according to the RRC state. In RRC_IDLE, public land mobile network (PLMN) selection, broadcast of system information (SI), cell re-selection mobility, core network (CN) paging and discontinuous reception (DRX) configured by NAS may be performed. The UE shall have been allocated an identifier (ID) which uniquely identifies the UE in a tracking area. No RRC context stored in the BS.

In RRC_CONNECTED, the UE has an RRC connection with the network (i.e. E-UTRAN/NG-RAN). Network-CN connection (both C/U-planes) is also established for UE. The UE AS context is stored in the network and the UE. The RAN knows the cell which the UE belongs to. The network can transmit and/or receive data to/from UE. Network controlled mobility including measurement is also performed.

Most of operations performed in RRC_IDLE may be performed in RRC_INACTIVE. But, instead of CN paging in RRC_IDLE, RAN paging is performed in RRC_INACTIVE. In other words, in RRC_IDLE, paging for mobile terminated (MT) data is initiated by core network and paging area is managed by core network. In RRC_INACTIVE, paging is initiated by NG-RAN, and RAN-based notification area (RNA) is managed by NG-RAN. Further, instead of DRX for CN paging configured by NAS in RRC_IDLE, DRX for RAN paging is configured by NG-RAN in RRC_INACTIVE. Meanwhile, in RRC_INACTIVE, 5GC-NG-RAN connection (both C/U-planes) is established for UE, and the UE AS context is stored in NG-RAN and the UE. NG-RAN knows the RNA which the UE belongs to.

NAS layer is located at the top of the RRC layer. The NAS control protocol performs the functions, such as authentication, mobility management, security control.

The physical channels may be modulated according to OFDM processing and utilizes time and frequency as radio resources. The physical channels consist of a plurality of orthogonal frequency division multiplexing (OFDM) symbols in time domain and a plurality of subcarriers in frequency domain. One subframe consists of a plurality of OFDM symbols in the time domain. A resource block is a resource allocation unit, and consists of a plurality of OFDM symbols and a plurality of subcarriers. In addition, each subframe may use specific subcarriers of specific OFDM symbols (e.g. first OFDM symbol) of the corresponding subframe for a physical downlink control channel (PDCCH), i.e. L1/L2 control channel. A transmission time interval (TTI) is a basic unit of time used by a scheduler for resource allocation. The TTI may be defined in units of one or a plurality of slots, or may be defined in units of mini-slots.

The transport channels are classified according to how and with what characteristics data are transferred over the radio interface. DL transport channels include a broadcast channel (BCH) used for transmitting system information, a downlink shared channel (DL-SCH) used for transmitting user traffic or control signals, and a paging channel (PCH) used for paging a UE. UL transport channels include an uplink shared channel (UL-SCH) for transmitting user traffic or control signals and a random access channel (RACH) normally used for initial access to a cell.

Different kinds of data transfer services are offered by MAC sublayer. Each logical channel type is defined by what type of information is transferred. Logical channels are classified into two groups: control channels and traffic channels.

Control channels are used for the transfer of control plane information only. The control channels include a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH) and a dedicated control channel (DCCH). The BCCH is a DL channel for broadcasting system control information. The PCCH is DL channel that transfers paging information, system information change notifications. The CCCH is a channel for transmitting control information between UEs and network. This channel is used for UEs having no RRC connection with the network. The DCCH is a point-to-point bi-directional channel that transmits dedicated control information between a UE and the network. This channel is used by UEs having an RRC connection.

Traffic channels are used for the transfer of user plane information only. The traffic channels include a dedicated traffic channel (DTCH). The DTCH is a point-to-point channel, dedicated to one UE, for the transfer of user information. The DTCH can exist in both UL and DL.

Regarding mapping between the logical channels and transport channels, in DL, BCCH can be mapped to BCH, BCCH can be mapped to DL-SCH, PCCH can be mapped to PCH, CCCH can be mapped to DL-SCH, DCCH can be mapped to DL-SCH, and DTCH can be mapped to DL-SCH. In UL, CCCH can be mapped to UL-SCH, DCCH can be mapped to UL- SCH, and DTCH can be mapped to UL-SCH.

Paging is described. Section 7.1 of 3GPP TS 38.304 V15.0.0 (2018-06) can be referred.

The UE may use discontinuous reception (DRX) in RRC_IDLE and RRC_INACTIVE state in order to reduce power consumption. The UE monitors one paging occasion (PO) per DRX cycle. A PO is a set of PDCCH monitoring occasions and can consist of multiple time slots (e.g. subframe or OFDM symbol) where paging downlink control information (DCI) can be sent. One Paging frame (PF) is one radio frame and may contain one or multiple PO(s) or starting point of a PO.

In multi-beam operations, the length of one PO is one period of beam sweeping and the UE can assume that the same paging message is repeated in all beams of the sweeping pattern and thus the selection of the beam(s) for the reception of the paging message is up to UE implementation. The paging message is same for both RAN initiated paging and CN initiated paging.

The UE initiates RRC connection resume procedure upon receiving RAN paging. If the UE receives a CN initiated paging in RRC_INACTIVE state, the UE moves to RRC_IDLE and informs NAS.

PF, PO are determined by the following equations.

System frame number (SFN) for the PF is determined by Equation 1.

[Equation 1]

(SFN + PF_offset) mod T = (T div N)*(UE_ID mod N)

Index (i_s), indicating the start of a set of PDCCH monitoring occasions for the paging DCI, is determined by Equation 2.

[Equation 2]

i_s = floor (UE_ID/N) mod Ns; where, Ns = max (1, nB/T)

The PDCCH monitoring occasions for paging are determined according to paging-SearchSpace if configured and according to the default association (i.e. PDCCH monitoring occasions for paging are same as for remaining minimum SI (RMSI)) otherwise.

For default association, Ns is either 1 or 2. For Ns = 1, there is only one PO which starts in the PF. For Ns = 2, PO is either in the first half frame (i_s = 0) or the second half frame (i_s = 1) of the PF.

For non-default association (i.e. when paging- SearchSpace is used), the UE monitors the (i_s + 1)^th PO where the first PO starts in the PF.

The following parameters are used for the calculation of PF and i_s above:

- T: DRX cycle of the UE (T is determined by the shortest of the UE specific DRX value, if configured by RRC or upper layers, and a default DRX value broadcast in system information. If UE specific DRX is not configured by upper layers, the default value is applied)

- nB: number of total paging occasions in T

- N: min(T, nB)

- PF_offset: offset used for PF determination

- UE_ID: international mobile subscriber identity (IMSI) mod 1024

Parameters nB, PF_offset, and the length of default DRX cycle are signaled in SystemInformationBlock1.

If the UE has no IMSI, for instance when making an emergency call without universal subscriber identification module (USIM), the UE shall use as default identity UE_ID = 0 in the PF and i_s equations above.

IMSI is given as sequence of digits of type Integer (0..9). IMSI shall in the equation above be interpreted as a decimal integer number, where the first digit given in the sequence represents the highest order digit.

Wakeup signal (WUS) is described. Section 7.4 of 3GPP TS 36.304 V15.0.0 (2018-06) can be referred.

WUS is used to indicate that the UE shall attempt to receive paging in that cell. WUS may be used for the purpose of power consumption. WUS may be specifically beneficial to MTC UEs and/or narrowband (NB)-IoT UEs. When the UE supports WUS and WUS configuration is provided in system information, the UE shall monitor WUS using the WUS parameters provided in system information. When DRX is used and the UE detects WUS, the UE shall monitor the following PO. When extended DRX is used and the UE detects WUS, the UE shall monitor the following numPOs or until a paging message is received, whichever is earlier. The numPOs is the number of consecutive POs mapped to one WUS provided in system information where numPOs≥1. If the UE does not detect WUS, the UE is not required to monitor the following PO(s).

Enabling/disabling of WUS may be configured per cell. After cell reselection, the UE may monitor every PO until the next WUS or until paging time window (PTW) ends (whichever is first). If the network sends direct indication or paging for SI modification, then WUS may be sent.

NR standalone operation on unlicensed bands is described. NR standalone operation on unlicensed bands is now studied. In LTE LAA, a cell on an unlicensed bands is not considered as primary cell (PCell), but only as secondary cell (SCell). On the other hand, In NR standalone operation on unlicensed bands, a cell on an unlicensed bands can be considered as a PCell. Therefore, paging reception should be newly considered in the cell on the unlicensed band.

Generally a paging cycle is defined to allow UEs to wake up at predefined time slots to receive possible paging message. The paging configuration could be cell specific or UE specific. It has been already agreed to support paging for RRC_IDLE where paging message is scheduled by DCI carried by PDCCH and is transmitted in the associated PDSCH.

For paging message transmission on unlicensed bands, the problem of uncertainty of channel availability makes paging DCI hard to be sent out at the predefined time slot. That is, UEs may miss its paging message. In other words, paging transmission may also be dropped due to LBT failure. Such dropped paging transmission will cause delayed mobile terminating (MT) access because gNB and UE should wait until the next paging occasion occurs for the UE. Therefore, how to recover from missing paging transmissions due to LBT failure in terms of the paging delay and extra UE power consumption should be addressed.

To alleviate impact of LBT failure, extending a monitoring window for PO may be considered. This is the simplest solution. If the UE monitors extended monitoring window for PO, gNB would try LBT more times and the success probability of LBT would be increased. As a result, the UE may likely receive paging. However, the power consumption would increase because all UEs would monitor the extended longer window. Moreover, the extended monitoring window would consist of consecutive time slot. If once the LBT is failed, the following LBT may be likely failed in a short time. So, the possibility of LBT failure of the extended monitoring window would be high. The channel occupancy time (COT) of other node which causes LBT failure would not be ended in a short time.

Furthermore, PDCCH monitoring occasions for default association paging are same as for RMSI. When RMSI transmission is dropped due to LBT failure, the overlapped paging transmission will be likely dropped. Therefore, a solution to solve missing SI transmission could be also applicable to default association paging in NR unlicensed band. However, PDCCH monitoring occasions for non-default association paging are according to the paging search space. Therefore, a solution for non-default association should be considered separately.

1. Embodiment 1

According to the embodiment of the present invention shown in FIG. 7, the wireless device can monitor additional PO (or, supplementary PO) which is not originally associated to the wireless device based on the ID of the wireless device, in addition to PO associated to the wireless device based on the ID of the wireless device. In the description below, a UE is used as an example of the wireless device.

In step S700, the UE calculates a first PO based on an ID of the UE. The UE may calculate PF based on the ID of the UE.

In step S710, the UE receives information on timing of monitoring paging from a network. The information on the timing of monitoring paging may be bitmap information. Each bit of the bitmap information may be respectively mapped to each PO of multiple POs including the first PO and a second PO. The each bit of the bitmap information may indicate whether the each PO mapped to the each bit is monitored or not. The information on the timing of monitoring paging may be received via SIB1 (i.e. RMSI) and/or PDCCH.

Furthermore, the UE may receive WUS from the network. The WUS may indicate a group of UEs associated to one PO. The WUS may include a negative indicator for the group of UEs. The negative indicator may indicate that the group of UEs should not monitor the one PO associated to the group of UEs.

In step S720, the UE monitors the first PO.

The UE may monitor the first PO based on the received WUS. For example, the WUS may indicate a group of UEs associated to the first PO. The first PO may be monitored based on that the WUS indicates a group of UEs associated to the first PO and the UE is included in the group of UEs. That is, when the WUS indicates a group of UEs associated to the first PO and the UE is included in the group of UEs, the UE may monitor the first PO.

Alternatively, the UE may monitor the first PO when the UE does not WUS and does not receive the information on timing of monitoring paging (i.e. bitmap information).

Alternatively, the UE may monitor the first PO when the UE does not detect a discovery signal when the UE monitors the WUS.

In step S730, the UE determines whether the discovery signal is detected or not in the first PO. After the UE derives the cell quality and the cell quality is above the minimum cell selection value (e.g. Qrxlevmin), the UE may determine that the discovery signal is detected. On the other hand, after the UE derives the cell quality and the cell quality is below the minimum cell selection value (e.g. Qrxlevmin), or the UE cannot derive the cell quality, the UE may determine that the discovery signal is not detected. The discovery signal may include at least one of a synchronization signal (SS)/physical broadcast channel (PBCH) block and/or a channel state information reference signal (CSI-RS). When the UE detects the discovery signal, the UE may derive cell quality from the received discovery signal.

If the UE detects the discovery signal in the first PO, the UE would not monitor additional PO.

When the discovery signal is not detected in the first PO, the UE calculates a second PO based on the information on the timing of monitoring paging, not based on the ID of the UE, and monitors the second PO. The second PO may be a PO associated with other UEs by the information on the timing of monitoring paging, but not associated with the UE by the ID of the UE. That is, when the UE does not detect the discovery signal in the first PO, the UE would back to sleep and monitor the second PO, i.e. supplementary one or more POs, informed by the information on the timing of monitoring paging. The network may configure "N" value instead of the bitmap information when the number of supplementary PO is one.

The first PO may be configured in a first frequency, and the second PO may be configured in a second frequency different from the first frequency. At least one of the first frequency or the second frequency may be on unlicensed bands. The first PO and the second PO may be monitored based on a paging search space.

Alternatively, if the UE receives the WUS with negative indicator and the UE is included in the group indicated by the negative indicator and/or the UE receives dedicated bitmap information for negative indicator, the UE may not monitor the first PO but monitor the second PO, i.e. the supplementary one or more POs, informed by the information on the timing of monitoring paging.

Alternatively, if the UE receives the WUS indicating a group of UEs but the UE is not included in the group indicated by the WUS, the UE would back to sleep and would not monitor the first PO and the second PO, i.e. supplementary one or more POs, informed by the information on the timing of monitoring paging.

According to the embodiment 1 of the present invention shown in FIG. 7, the UE can quickly receive paging in the additional monitoring window without waiting until the next monitoring window occurs. Therefore, delay of paging reception can be reduced, and UE power consumption can be saved compared to monitoring extended paging occasion.

Detailed examples of the embodiment 1 of the present invention described above are described as follows.

(1) Example 1: A case that the UE receives the WUS and the UE is in the group, or the UE does not support WUS and does not receive dedicated bitmap information or the UE does not detect the discovery signal when the UE monitors the WUS

In this example, the UE monitors additional PO according to the received bitmap information. For example, the UE receives bitmap information (e.g. via SIB1) and/or WUS from network. The bitmap information may indicate the timing of monitoring paging. If the UE receives WUS and the UE is in the group indicated by the WUS, or the UE does not support WUS or the UE does not detect the discovery signal when the UE monitors the WUS, the UE monitors the original associated PO at first. If the UE detects the discovery signal on time, i.e. during the original associated PO, the UE would not monitor additional PO. However, if the UE does not detect the discovery signal on time, i.e. during the original associated PO, the UE would back to sleep and monitor the additional PO indicated by the received bitmap information.

In other words, additional paging transmission in other additional PO can be considered. The gNB broadcasts a parameter to indicate the location of additional PO. The parameter can be bitmap information or an integer value K. If the UE monitors the PO determined by UE ID and the UE cannot find the discovery signal (or the received signal strength of the discovery signal is lower than threshold), the UE would monitor additional PO. If the UE detects the discovery signal or paging indication at PO determined by UE ID, the UE would not monitor additional PO.

In FIG. 8, it is assumed that a subcarrier spacing is 15 kHz, Ns is 2, DRX cycle is 320ms, and number of POs in DRX cycle is 64. Furthermore, it is assumed for a paging search space configuration that a periodicity is 5ms, offset is 0, duration is 2 slots, a value of monitoringSymbolsWithinSlot is "00100000100000" and CORESET-time-duration is 4 OFDM symbols.

In FIG. 8, the received bitmap information is "1100". The UE monitors its own PO ((i_s+1)^th PO), and optionally the next (i_s+2)^th PO when the UE does not detect the discovery signal in its own PO. That is, when the UE associated to the first PO does not detect the discovery signal on the first PO, the UE additionally monitors the second PO.

In FIG. 9, it is assumed that a subcarrier spacing is 15 kHz, Ns is 2, DRX cycle is 320ms, and number of POs in DRX cycle is 64. Furthermore, it is assumed for a paging search space configuration that a periodicity is 5ms, offset is 0, duration is 2 slots, a value of monitoringSymbolsWithinSlot is "00100000100000" and CORESET-time-duration is 4 OFDM symbols.

In FIG. 9, the received bitmap information is "1010". The UE monitors its own PO ((i_s+1)^th PO) and optionally the (i_s+3)^th PO when the UE does not detect the discovery signal in its own PO. That is, when the UE associated to the first PO does not detect the discovery signal on the first PO, the UE additionally monitors the third PO.

(2) Example 2: A case that the UE receives the WUS with negative indicator and the UE is included in the group indicated by the negative indicator, or the UE receives dedicated bitmap information for negative indicator

According to the embodiment 1 of the present invention, additional search space for paging is not needed. However, the paging capacity may be lowered due to the delayed paging which may take up much space of the next paging occasion. Therefore, a negative indicator which notifies the group of UEs associated to the PO when the PO is full due to the delayed paging of other group of UEs may be further indicated. In other words, if the UE receives WUS with the negative indicator and the UE is included in the group indicated by the negative indicator, the UE monitors the next PO indicated by the received bitmap information, instead of its own PO.

In FIG. 10, it is assumed that a subcarrier spacing is 15 kHz, Ns is 2, DRX cycle is 320ms, and number of POs in DRX cycle is 64. Furthermore, it is assumed for a paging search space configuration that a periodicity is 5ms, offset is 0, duration is 2 slots, a value of monitoringSymbolsWithinSlot is "00100000100000" and CORESET-time-duration is 4 OFDM symbols.

In FIG. 10, the received bitmap information is "1010". A UE associated to the first PO does not detect the discovery signal on the first PO, the UE additionally monitors the third PO. Then, another UE associated to the third PO monitors WUS with negative indicator and the UE determines that the UE is included in the group indicated by the negative indicator. Then, the UE associated to the third PO acknowledges that delayed PO from the first PO occupied third PO and the UE should monitor the (i_s+3)^th PO (i.e. 5^th PO), instead of its own PO. Therefore, the UE associated to the third PO does not monitor the third PO but monitor the fifth PO.

In FIG. 11, it is assumed that a subcarrier spacing is 15 kHz, Ns is 2, DRX cycle is 320ms, and number of POs in DRX cycle is 64. Furthermore, it is assumed for a paging search space configuration that a periodicity is 5ms, offset is 0, duration is 2 slots, a value of monitoringSymbolsWithinSlot is "00100000100000" and CORESET-time-duration is 4 OFDM symbols.

In FIG. 11, the received bitmap information is "1010". A UE associated to the first PO does not detect the discovery signal on the first PO, the UE additionally monitors the third PO. Furthermore, the negative indicator may be notified by the dedicated bitmap information via PDCCH. In FIG. 11, the dedicated bitmap information is "0010". The network transmits the dedicated bitmap information to group of UEs which are originally associated to the third PO. Since the dedicated bitmap information is “0010”, the UE associated to the third PO acknowledges that delayed PO from the first PO occupied third PO and the UE should monitor the (i_s+3)^th PO (i.e. 5^th PO), instead of its own PO. Therefore, the UE associated to the third PO does not monitor the third PO but monitor the fifth PO.

By using additional other POs not associated to the UE by UE ID, more opportunities per DRX cycle for the UE to receive the paging can be introduced. The additional locations can be provided in time domain by configuring the additional PO (i.e. multiple POs) to a UE. Only the UEs corresponding to the PO in which LBT failure occurs will monitor the additional PO. So, the power consumption would be less compared to using extended monitoring window. The possibility of LBT failure may also be lower than using extended monitoring window because of time distance between the PO determined by UE ID and the additional PO. In addition, the resources at the additional PO location are originally allocated for paging usage. So, data transmission resources are not reduced/impacted due to the additional paging.

2. Embodiment 2

On unlicensed bands, channel may be occupied other devices. So, if the channel is not busy and LBT is succeeded, it would be better to monitor POs in extended time. So, the extended window for monitoring PO and overlapping the POs may be considered by the embodiment 2 of the present invention.

The detailed operations according to the embodiment 2 of the present invention may be as follows.

(1) The UE calculates the PF/PO with its UE_ID.

(2) The UE receives extended paging parameters with N and Ns. (e.g. via SIB1).

The information on an extended window size, an overlapping window size and group size may be included in extended paging parameters. N is number of PFs in the DRX cycle of the UE. Ns may is the number of POs for one PF.

(3) The UEs associated to the first PO to (group size)th PO monitor the paging as follows.

- The UEs associated to the first PO monitor first PO from the start point of first PO(i.e. #1POS) to the (#1POS) plus extended window size (i.e. end point of first PO (i.e. #1POE)).

- The UEs associated to the second PO monitor second PO from the (#1POE) minus overlapping window size (i.e. #2POS) to the (#2POS) plus extended window size (i.e. #2POE).

- Likewise, the UEs associated to the (group size)th PO monitor (group size)th PO from the (#(group size-1)POE) minus overlapping window size to the (#(group size)POS) plus extended window size.

(4) The UEs associated to the (X*group size+1)th PO (X is 1 to (N*Ns)/group size) monitor from (X*group size+1)th PO to the (#(X*group size+1) POS) plus extended window size.

(5) The UEs associated to the (X*group size+Z)th PO (Z is 2 to group size) monitor from (#(X*group size+Z-1)POE) minus overlapping window size to the (#(X*group size+Z)POS) plus extended window size.

In FIG. 12, it is assumed that a subcarrier spacing is 15 kHz, Ns is 2, DRX cycle is 320ms, and number of POs in DRX cycle is 64. Furthermore, it is assumed for a paging search space configuration that a periodicity is 8 slots, offset is 0, duration is 2 slots, a value of monitoringSymbolsWithinSlot is "00100000100000" and CORESET-time-duration is 4 OFDM symbols.

In FIG. 12, the extended window size is 1 slot and overlapping window size is 1 slot and the group size is 2. Therefore, when LBT is succeeded in the first PO, the UEs associated to the first PO and the second PO (i.e. group size is 2) monitor extended POs starting from the start point of the first PO and ending at the end point of the second PO.

According to the embodiment 2 of the present invention shown in FIG. 12, the UE can perform extensible paging monitoring when LBT is succeeded.

A UE includes a processor 1310, a power management module 1311, a battery 1312, a display 1313, a keypad 1314, a subscriber identification module (SIM) card 1315, a memory 1320, a transceiver 1330, one or more antennas 1331, a speaker 1340, and a microphone 1341.

The processor 1310 may be configured to implement proposed functions, procedures and/or methods described in this description. Layers of the radio interface protocol may be implemented in the processor 1310. The processor 1310 may include application-specific integrated circuit (ASIC), other chipset, logic circuit and/or data processing device. The processor 1310 may be an application processor (AP). The processor 1310 may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), a modem (modulator and demodulator). An example of the processor 1310 may be found in SNAPDRAGON^TM series of processors made by Qualcomm^®, EXYNOS^TM series of processors made by Samsung^®, A series of processors made by Apple^®, HELIO^TM series of processors made by MediaTek^®, ATOM^TM series of processors made by Intel^® or a corresponding next generation processor.

The processor 1310 is configured to calculate a first PO based on an ID of the UE. The UE may calculate PF based on the ID of the UE.

The processor 1310 is configured to control the transceiver 1330 to receive information on timing of monitoring paging from a network. The information on the timing of monitoring paging may be bitmap information. Each bit of the bitmap information may be respectively mapped to each PO of multiple POs including the first PO and a second PO. The each bit of the bitmap information may indicate whether the each PO mapped to the each bit is monitored or not. The information on the timing of monitoring paging may be received via SIB1 (i.e. RMSI) and/or PDCCH.

Furthermore, the processor 1310 may be configured to control the transceiver 1330 to receive WUS from the network. The WUS may indicate a group of UEs associated to one PO. The WUS may include a negative indicator for the group of UEs. The negative indicator may indicate that the group of UEs should not monitor the one PO associated to the group of UEs.

The processor 1310 is configured to control the transceiver 1330 to monitor the first PO.

The processor 1310 may be configured to control the transceiver 1330 to monitor the first PO based on the received WUS. For example, the WUS may indicate a group of UEs associated to the first PO. The first PO may be monitored based on that the WUS indicates a group of UEs associated to the first PO and the UE is included in the group of UEs. That is, when the WUS indicates a group of UEs associated to the first PO and the UE is included in the group of UEs, the processor 1310 may control the transceiver 1330 to monitor the first PO.

The processor 1310 is configured to determine whether the discovery signal is detected or not in the first PO. After the UE derives the cell quality and the cell quality is above the minimum cell selection value (e.g. Qrxlevmin), the processor 1310 may determine that the discovery signal is detected. On the other hand, after the UE derives the cell quality and the cell quality is below the minimum cell selection value (e.g. Qrxlevmin), or the UE cannot derive the cell quality, the processor 1310 may determine that the discovery signal is not detected. The discovery signal may include at least one of a synchronization signal (SS)/physical broadcast channel (PBCH) block and/or a channel state information reference signal (CSI-RS). When the UE detects the discovery signal, the processor 1310 may be configured to derive cell quality from the received discovery signal.

When the discovery signal is not detected in the first PO, the processor 1310 is configured to calculate a second PO based on the information on the timing of monitoring paging, not based on the ID of the UE, and to control the transceiver 1330 to monitor the second PO. The second PO may be a PO associated with other UEs by the information on the timing of monitoring paging, but not associated with the UE by the ID of the UE. That is, when the UE does not detect the discovery signal in the first PO, the UE would back to sleep and monitor the second PO, i.e. supplementary one or more POs, informed by the information on the timing of monitoring paging. The network may configure "N" value instead of the bitmap information when the number of supplementary PO is one.

The power management module 1311 manages power for the processor 1310 and/or the transceiver 1330. The battery 1312 supplies power to the power management module 1311. The display 1313 outputs results processed by the processor 1310. The keypad 1314 receives inputs to be used by the processor 1310. The keypad 1314 may be shown on the display 1313. The SIM card 1315 is an　integrated circuit　that is intended to　securely store the　international mobile subscriber identity　(IMSI) number and its related　key, which are used to identify and authenticate subscribers on　mobile telephony　devices (such as　mobile phones　and　computers). It is also possible to store contact information on many SIM cards.

The memory 1320 is operatively coupled with the processor 1310 and stores a variety of information to operate the processor 1310. The memory 1320 may include read-only memory (ROM), random access memory (RAM), flash memory, memory card, storage medium and/or other storage device. When the embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The modules can be stored in the memory 1320 and executed by the processor 1310. The memory 1320 can be implemented within the processor 1310 or external to the processor 1310 in which case those can be communicatively coupled to the processor 1310 via various means as is known in the art.

The transceiver 1330 is operatively coupled with the processor 1310, and transmits and/or receives a radio signal. The transceiver 1330 includes a transmitter and a receiver. The transceiver 1330 may include baseband circuitry to process radio frequency signals. The transceiver 1330 controls the one or more antennas 1331 to transmit and/or receive a radio signal.

The speaker 1340 outputs sound-related results processed by the processor 1310. The microphone 1341 receives sound-related inputs to be used by the processor 1310.

According to the embodiment of the present invention shown in FIG. 13, the UE can quickly receive paging in the additional monitoring window without waiting until the next monitoring window occurs. Therefore, delay of paging reception can be reduced, and UE power consumption can be saved compared to monitoring extended paging occasion.

The present invention may be applied to various future technologies, such as AI.

<AI>

AI refers to artificial intelligence and/or the field of studying methodology for making it. Machine learning is a field of studying methodologies that define and solve various problems dealt with in AI. Machine learning may be defined as an algorithm that enhances the performance of a task through a steady experience with any task.

An artificial neural network (ANN) is a model used in machine learning. It can mean a whole model of problem-solving ability, consisting of artificial neurons (nodes) that form a network of synapses. An ANN can be defined by a connection pattern between neurons in different layers, a learning process for updating model parameters, and/or an activation function for generating an output value. An ANN may include an input layer, an output layer, and optionally one or more hidden layers. Each layer may contain one or more neurons, and an ANN may include a synapse that links neurons to neurons. In an ANN, each neuron can output a summation of the activation function for input signals, weights, and deflections input through the synapse. Model parameters are parameters determined through learning, including deflection of neurons and/or weights of synaptic connections. The hyper-parameter means a parameter to be set in the machine learning algorithm before learning, and includes a learning rate, a repetition number, a mini batch size, an initialization function, etc. The objective of the ANN learning can be seen as determining the model parameters that minimize the loss function. The loss function can be used as an index to determine optimal model parameters in learning process of ANN.

Machine learning can be divided into supervised learning, unsupervised learning, and reinforcement learning, depending on the learning method. Supervised learning is a method of learning ANN with labels given to learning data. Labels are the answers (or result values) that ANN must infer when learning data is input to ANN. Unsupervised learning can mean a method of learning ANN without labels given to learning data. Reinforcement learning can mean a learning method in which an agent defined in an environment learns to select a behavior and/or sequence of actions that maximizes cumulative compensation in each state.

Machine learning, which is implemented as a deep neural network (DNN) that includes multiple hidden layers among ANN, is also called deep learning. Deep learning is part of machine learning. In the following, machine learning is used to mean deep learning.

The AI device 1400 may be implemented as a stationary device or a mobile device, such as a TV, a projector, a mobile phone, a smartphone, a desktop computer, a notebook, a digital broadcasting terminal, a PDA, a PMP, a navigation device, a tablet PC, a wearable device, a set-top box (STB), a digital multimedia broadcasting (DMB) receiver, a radio, a washing machine, a refrigerator, a digital signage, a robot, a vehicle, etc.

Referring to FIG. 14, the AI device 1400 may include a communication part 1410, an input part 1420, a learning processor 1430, a sensing part 1440, an output part 1450, a memory 1460, and a processor 1470.

The communication part 1410 can transmit and/or receive data to and/or from external devices such as the AI devices and the AI server using wire and/or wireless communication technology. For example, the communication part 1410 can transmit and/or receive sensor information, a user input, a learning model, and a control signal with external devices. The communication technology used by the communication part 1410 may include a global system for mobile communication (GSM), a code division multiple access (CDMA), an LTE/LTE-A, a 5G, a WLAN, a Wi-Fi, Bluetooth^TM, radio frequency identification (RFID), infrared data association (IrDA), ZigBee, and/or near field communication (NFC).

The input part 1420 can acquire various kinds of data. The input part 1420 may include a camera for inputting a video signal, a microphone for receiving an audio signal, and a user input part for receiving information from a user. A camera and/or a microphone may be treated as a sensor, and a signal obtained from a camera and/or a microphone may be referred to as sensing data and/or sensor information. The input part 1420 can acquire input data to be used when acquiring an output using learning data and a learning model for model learning. The input part 1420 may obtain raw input data, in which case the processor 1470 or the learning processor 1430 may extract input features by preprocessing the input data.

The learning processor 1430 may learn a model composed of an ANN using learning data. The learned ANN can be referred to as a learning model. The learning model can be used to infer result values for new input data rather than learning data, and the inferred values can be used as a basis for determining which actions to perform. The learning processor 1430 may perform AI processing together with the learning processor of the AI server. The learning processor 1430 may include a memory integrated and/or implemented in the AI device 1400. Alternatively, the learning processor 1430 may be implemented using the memory 1460, an external memory directly coupled to the AI device 1400, and/or a memory maintained in an external device.

The sensing part 1440 may acquire at least one of internal information of the AI device 1400, environment information of the AI device 1400, and/or the user information using various sensors. The sensors included in the sensing part 1440 may 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, a light detection and ranging (LIDAR), and/or a radar.

The output part 1450 may generate an output related to visual, auditory, tactile, etc. The output part 1450 may include a display unit for outputting visual information, a speaker for outputting auditory information, and/or a haptic module for outputting tactile information.

The memory 1460 may store data that supports various functions of the AI device 1400. For example, the memory 1460 may store input data acquired by the input part 1420, learning data, a learning model, a learning history, etc.

The processor 1470 may determine at least one executable operation of the AI device 1400 based on information determined and/or generated using a data analysis algorithm and/or a machine learning algorithm. The processor 1470 may then control the components of the AI device 1400 to perform the determined operation. The processor 1470 may request, retrieve, receive, and/or utilize data in the learning processor 1430 and/or the memory 1460, and may control the components of the AI device 1400 to execute the predicted operation and/or the operation determined to be desirable among the at least one executable operation. The processor 1470 may generate a control signal for controlling the external device, and may transmit the generated control signal to the external device, when the external device needs to be linked to perform the determined operation. The processor 1470 may obtain the intention information for the user input and determine the user's requirements based on the obtained intention information. The processor 1470 may use at least one of a speech-to-text (STT) engine for converting speech input into a text string and/or a natural language processing (NLP) engine for acquiring intention information of a natural language, to obtain the intention information corresponding to the user input. At least one of the STT engine and/or the NLP engine may be configured as an ANN, at least a part of which is learned according to a machine learning algorithm. At least one of the STT engine and/or the NLP engine may be learned by the learning processor 1430 and/or learned by the learning processor of the AI server, and/or learned by their distributed processing. The processor 1470 may collect history information including the operation contents of the AI device 1400 and/or the user's feedback on the operation, etc. The processor 1470 may store the collected history information in the memory 1460 and/or the learning processor 1430, and/or transmit to an external device such as the AI server. The collected history information can be used to update the learning model. The processor 1470 may control at least some of the components of AI device 1400 to drive an application program stored in memory 1460. Furthermore, the processor 1470 may operate two or more of the components included in the AI device 1400 in combination with each other for driving the application program.

Referring to FIG. 15, in the AI system, at least one of an AI server 1520, a robot 1510a, an autonomous vehicle 1510b, an XR device 1510c, a smartphone 1510d and/or a home appliance 1510e is connected to a cloud network 1500. The robot 1510a, the autonomous vehicle 1510b, the XR device 1510c, the smartphone 1510d, and/or the home appliance 1510e to which the AI technology is applied may be referred to as AI devices 1510a to 1510e.

The cloud network 1500 may refer to a network that forms part of a cloud computing infrastructure and/or resides in a cloud computing infrastructure. The cloud network 1500 may be configured using a 3G network, a 4G or LTE network, and/or a 5G network. That is, each of the devices 1510a to 1510e and 1520 consisting the AI system may be connected to each other through the cloud network 1500. In particular, each of the devices 1510a to 1510e and 1520 may communicate with each other through a base station, but may directly communicate with each other without using a base station.

The AI server 1500 may include a server for performing AI processing and a server for performing operations on big data. The AI server 1500 is connected to at least one or more of AI devices constituting the AI system, i.e. the robot 1510a, the autonomous vehicle 1510b, the XR device 1510c, the smartphone 1510d and/or the home appliance 1510e through the cloud network 1500, and may assist at least some AI processing of the connected AI devices 1510a to 1510e. The AI server 1500 can learn the ANN according to the machine learning algorithm on behalf of the AI devices 1510a to 1510e, and can directly store the learning models and/or transmit them to the AI devices 1510a to 1510e. The AI server 1500 may receive the input data from the AI devices 1510a to 1510e, infer the result value with respect to the received input data using the learning model, generate a response and/or a control command based on the inferred result value, and transmit the generated data to the AI devices 1510a to 1510e. Alternatively, the AI devices 1510a to 1510e may directly infer a result value for the input data using a learning model, and generate a response and/or a control command based on the inferred result value.

Various embodiments of the AI devices 1510a to 1510e to which the technical features of the present invention can be applied will be described. The AI devices 1510a to 1510e shown in FIG. 15 can be seen as specific embodiments of the AI device 1400 shown in FIG. 14.

In view of the exemplary systems described herein, methodologies that may be implemented in accordance with the disclosed subject matter have been described with reference to several flow diagrams. While for purposed of simplicity, the methodologies are shown and described as a series of steps or blocks, it is to be understood and appreciated that the claimed subject matter is not limited by the order of the steps or blocks, as some steps may occur in different orders or concurrently with other steps from what is depicted and described herein. Moreover, one skilled in the art would understand that the steps illustrated in the flow diagram are not exclusive and other steps may be included or one or more of the steps in the example flow diagram may be deleted without affecting the scope of the present disclosure.

Claims in the present description can be combined in a various way. For instance, technical features in method claims of the present description can be combined to be implemented or performed in an apparatus, and technical features in apparatus claims can be combined to be implemented or performed in a method. Further, technical features in method claim(s) and apparatus claim(s) can be combined to be implemented or performed in an apparatus. Further, technical features in method claim(s) and apparatus claim(s) can be combined to be implemented or performed in a method.

Claims

A method performed by a wireless device in a wireless communication system, the method comprising:

calculating a first paging occasion (PO) based on an identifier (ID) of the wireless device;

receiving information on timing of monitoring paging from a network;

monitoring the first PO;

When a discovery signal is not detected in the first PO:

calculating a second PO based on the information on the timing of monitoring paging, not based on the ID of the wireless device; and

monitoring the second PO,

wherein the second PO is a PO associated with other wireless device, but not associated with the wireless device by the ID of the wireless device.
The method of claim 1, wherein the information on the timing of monitoring paging is bitmap information.
The method of claim 2, wherein each bit of the bitmap information is respectively mapped to each PO of multiple POs including the first PO and the second PO, and

wherein the each bit indicates whether the each PO mapped to the each bit is monitored or not.
The method of claim 1, wherein the first PO is configured in a first frequency, and

wherein the second PO is configured in a second frequency different from the first frequency.
The method of claim 1, wherein at least one of the first frequency or the second frequency is on unlicensed bands.
The method of claim 1, wherein the discovery signal is not detected in the first PO when a cell quality is below than a minimum cell selection value and/or the cell quality cannot be derived.
The method of claim 1, wherein the discovery signal includes at least one of a synchronization signal (SS)/physical broadcast channel (PBCH) block and/or a channel state information reference signal (CSI-RS).
The method of claim 1, further comprising receiving a wake-up signal (WUS) from the network.
The method of claim 8, wherein the WUS indicates a group of wireless devices associated to one PO.
The method of claim 9, wherein the first PO is monitored based on that the WUS indicates a group of wireless devices associated to the first PO and the wireless device is included in the group of wireless devices.
The method of claim 9, wherein the WUS includes a negative indicator for the group of wireless devices, and

wherein the negative indicator indicates that the group of wireless devices should not monitor the one PO associated to the group of wireless devices.
The method of claim 1, wherein the first PO and the second PO are monitored based on a paging search space.
The method of claim 1, wherein the wireless device is in communication with at least one of a user equipment, a network, and/or autonomous vehicles other than the wireless device.
A wireless device in a wireless communication system, the wireless device comprising:

a memory;

a transceiver; and

a processor, operably coupled to the memory and the transceiver, configured to:

calculate a first paging occasion (PO) based on an identifier (ID) of the wireless device,

control the transceiver to receive information on timing of monitoring paging from a network,

control the transceiver to monitor the first PO,

When a discovery signal is not detected in the first PO:

calculate a second PO based on the information on the timing of monitoring paging, not based on the ID of the wireless device, and

control the transceiver to monitor the second PO,

wherein the second PO is a PO associated with other wireless device, but not associated with the wireless device by the ID of the wireless device.