WO2019225908A1 - Method for transmitting and receiving downlink signal, and device therefor - Google Patents

Abstract

The present invention discloses a method for a terminal to receive a downlink signal in a wireless communication system. In particular, the method can: receive measurement report configuration information associated with a resource for a synchronization signal/physical broadcast channel (SS/PBCH) block; receive the SS/PBCH block through a plurality of orthogonal frequency divisional multiplexing (OFDM) symbols; and receive the downlink signal through the plurality of OFDM symbols on the basis of the measurement report configuration information.

Description

Method for transmitting / receiving downlink signal and apparatus therefor

The present invention relates to a method for transmitting and receiving a downlink signal and an apparatus therefor, and more particularly, to a method for transmitting and receiving a downlink signal based on a 'ReportQuantity' parameter setting associated with a CSI-RS resource or an SS / PBCH block resource. And an apparatus therefor.

As time goes by, more communication devices require more communication traffic, and a next generation 5G system, which is an improved wireless broadband communication than the existing LTE system, is required. Called NewRAT, these next-generation 5G systems are divided into communication scenarios such as Enhanced Mobile BroadBand (eMBB) / Ultra-reliability and low-latency communication (URLLC) / Massive Machine-Type Communications (mMTC).

Here, eMBB is a next generation mobile communication scenario having characteristics such as High Spectrum Efficiency, High User Experienced Data Rate, High Peak Data Rate, and URLLC is a next generation mobile communication scenario having characteristics such as Ultra Reliable, Ultra Low Latency, Ultra High Availability, etc. (Eg, V2X, Emergency Service, Remote Control), mMTC is a next generation mobile communication scenario with low cost, low energy, short packet, and mass connectivity. (e.g., IoT).

The present invention provides a method for transmitting and receiving a downlink signal and an apparatus therefor.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description. Could be.

In a wireless communication system according to an embodiment of the present invention, in a method for receiving a downlink signal by a terminal, measurement report configuration information associated with a resource for a synchronization signal / physical broadcast channel (SS / PBCH) block , The SS / PBCH block through the plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols, and the downlink signal through the plurality of OFDM symbols based on the measurement report configuration information. .

In this case, when the measurement report configuration information informs that the measurement of the SS / PBCH block is not reported, the downlink signal may not be received.

In addition, when the measurement report configuration information informs the report of the RSRP (Reference Signal Received Power) of the SS / PBCH block, the downlink signal may be received.

In addition, a resource for the SS / PBCH block may be included in a specific CSI resource setting.

The downlink signal may be at least one of a physical downlink shared channel (PDSCH) and a physical downlink control channel (PDCCH).

In addition, when the measurement report configuration information does not report the measurement of the SS / PBCH block (measurement), and if the downlink signal is CSI-RS (Channel State Information-Reference Signal) for beam management, the downlink The link signal can be received.

The terminal may communicate with at least one of a terminal, a network, a base station, and an autonomous vehicle other than the terminal.

In the wireless communication system according to the present invention, an apparatus for receiving a downlink signal, comprising: at least one processor; And at least one memory operatively coupled to the at least one processor and storing instructions that when executed by the at least one processor cause the at least one processor to perform a particular operation. The specific operation may include measurement report configuration (MEA) information associated with a resource for a Synchronization Signal / Physical Broadcast Channel (SS / PBCH) block, and through a plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols, The SS / PBCH block may be received and the downlink signal may be received through the plurality of OFDM symbols based on the measurement report configuration information.

In this case, when the measurement report configuration information informs that the measurement of the SS / PBCH block is not reported, the downlink signal may not be received.

In addition, when the measurement report configuration information informs the report of the RSRP (Reference Signal Received Power) of the SS / PBCH block, the downlink signal may be received.

In addition, a resource for the SS / PBCH block may be included in a specific CSI resource setting.

The downlink signal may be at least one of a physical downlink shared channel (PDSCH) and a physical downlink control channel (PDCCH).

In addition, when the measurement report configuration information does not report the measurement of the SS / PBCH block (measurement), and if the downlink signal is CSI-RS (Channel State Information-Reference Signal) for beam management, the downlink The link signal can be received.

In addition, the apparatus may be capable of communicating with at least one of a terminal, a network, a base station, and an autonomous vehicle other than the apparatus.

In a wireless communication system according to the present invention, a terminal for receiving a downlink signal, the terminal comprising: at least one transceiver; At least one processor; And at least one memory operatively coupled to the at least one processor and storing instructions that when executed by the at least one processor cause the at least one processor to perform a particular operation. The specific operation may include measurement report configuration information associated with a resource for a Synchronization Signal / Physical Broadcast Channel (SS / PBCH) block through the at least one transceiver and receive the at least one transceiver. The SS / PBCH block is received through a plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols, and the downlink signal is transmitted through the plurality of OFDM symbols based on the measurement report configuration information through the at least one transceiver. Can be received.

In a wireless communication system according to an embodiment of the present invention, in a method for transmitting a downlink signal by a base station, measurement report configuration information associated with resources for a synchronization signal / physical broadcast channel (SS / PBCH) block In this case, the SS / PBCH block may be transmitted through a plurality of orthogonal frequency divisional multiplexing (OFDM) symbols, and the downlink signal may be transmitted through the plurality of OFDM symbols based on the measurement report configuration information.

In the wireless communication system according to the present invention, a base station for transmitting a downlink signal, comprising: at least one transceiver; At least one processor; And at least one memory operatively coupled to the at least one processor and storing instructions that when executed by the at least one processor cause the at least one processor to perform a particular operation. The specific operation may include: transmitting measurement report configuration information associated with a resource for a Synchronization Signal / Physical Broadcast Channel (SS / PBCH) block through the at least one transceiver, and transmitting the at least one transceiver The SS / PBCH block is transmitted through a plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols, and the downlink signal is transmitted through the plurality of OFDM symbols based on the measurement report configuration information through the at least one transceiver. Can transmit

According to the present invention, it is possible to efficiently transmit and receive two or more downlink signals having different types.

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

FIG. 1 is a diagram illustrating a control plane and a user plane structure of a radio interface protocol between a terminal and an E-UTRAN based on a 3GPP radio access network standard.

2 is a diagram for explaining a physical channel used in the 3GPP system and a general signal transmission method using the same.

3 to 5 are diagrams for explaining the structure of a radio frame and slot used in the NR system.

6 to 8 are diagrams illustrating an example of transmission of an SS / PBCH block.

FIG. 9 is a diagram for explaining analog beamforming in an NR system.

10 to 14 are diagrams for explaining beam management in the NR system.

15 is a diagram for explaining an example of reporting channel state information.

16 is a diagram illustrating an example in which a terminal and a base station transmit and receive downlink signals according to an embodiment of the present invention.

17 is a block diagram illustrating components of a wireless device according to an embodiment of the present invention.

The construction, operation, and other features of the present invention will be readily understood by the embodiments of the present invention described with reference to the accompanying drawings. The embodiments described below are examples in which technical features of the present invention are applied to a 3GPP system.

Although the present specification describes an embodiment of the present invention using an LTE system, an LTE-A system, and an NR system, the embodiment of the present invention as an example may be applied to any communication system corresponding to the above definition.

In addition, the specification of the base station may be used as a generic term including a remote radio head (RRH), an eNB, a transmission point (TP), a reception point (RP), a relay, and the like.

The 3GPP-based communication standard provides downlink physical channels corresponding to resource elements carrying information originating from an upper layer and downlink corresponding to resource elements used by the physical layer but not carrying information originating from an upper layer. Physical signals are defined. For example, a physical downlink shared channel (PDSCH), a physical broadcast channel (PBCH), a physical multicast channel (PMCH), a physical control format indicator channel (physical control) format indicator channel (PCFICH), physical downlink control channel (PDCCH) and physical hybrid ARQ indicator channel (PHICH) are defined as downlink physical channels, reference signal and synchronization signal Is defined as downlink physical signals. A reference signal (RS), also referred to as a pilot, refers to a signal of a predefined special waveform that the gNB and the UE know from each other. For example, a cell specific RS, UE- UE-specific RS, positioning RS (PRS), and channel state information RS (CSI-RS) are defined as downlink reference signals. The 3GPP LTE / LTE-A standard corresponds to uplink physical channels corresponding to resource elements carrying information originating from a higher layer and resource elements used by the physical layer but not carrying information originating from an upper layer. Uplink physical signals are defined. For example, a physical uplink shared channel (PUSCH), a physical uplink control channel (PUCCH), and a physical random access channel (PRACH) are the uplink physical channels. A demodulation reference signal (DMRS) for uplink control / data signals and a sounding reference signal (SRS) used for uplink channel measurement are defined.

In the present invention, Physical Downlink Control CHannel (PDCCH) / Physical Control Format Indicator CHannel (PCFICH) / PHICH (Physical Hybrid automatic retransmit request Indicator CHannel) / PDSCH (Physical Downlink Shared CHannel) are respectively DCI (Downlink Control Information) / CFI ( Means a set of time-frequency resources or a set of resource elements that carry downlink format ACK / ACK / NACK (ACKnowlegement / Negative ACK) / downlink data, and also a physical uplink control channel (PUCCH) / physical (PUSCH). Uplink Shared CHannel / PACH (Physical Random Access CHannel) means a set of time-frequency resources or a set of resource elements that carry uplink control information (UCI) / uplink data / random access signals, respectively. PDCCH / PCFICH / PHICH / PDSCH / PUCCH / PUSCH / PRACH RE or the time-frequency resource or resource element (RE) assigned to or belonging to PDCCH / PCFICH / PHICH / PDSCH / PUCCH / PUSCH / PRACH, respectively. PDCCH / PCFICH / PHICH / PDSCH / PUCCH / PUSCH / PRACH Resource In the following, the expression that the user equipment transmits PUCCH / PUSCH / PRACH is used for uplink control information / uplink on or through PUSCH / PUCCH / PRACH, respectively. It is used in the same sense as transmitting a data / random access signal, and the expression that the gNB transmits PDCCH / PCFICH / PHICH / PDSCH is used for downlink data / control information on or through PDCCH / PCFICH / PHICH / PDSCH, respectively. It is used in the same sense as sending it.

Hereinafter, an OFDM symbol / subcarrier / RE to which CRS / DMRS / CSI-RS / SRS / UE-RS is assigned or configured is configured as CRS / DMRS / CSI-RS / SRS / UE-RS symbol / carrier. It is called / subcarrier / RE. For example, an OFDM symbol assigned or configured with a tracking RS (TRS) is referred to as a TRS symbol, and a subcarrier assigned or configured with a TRS is called a TRS subcarrier and is assigned a TRS. Alternatively, the configured RE is called a TRS RE. Also, a subframe configured for TRS transmission is called a TRS subframe. Also, a subframe in which a broadcast signal is transmitted is called a broadcast subframe or a PBCH subframe, and a subframe in which a sync signal (for example, PSS and / or SSS) is transmitted is a sync signal subframe or a PSS / SSS subframe. It is called. An OFDM symbol / subcarrier / RE to which PSS / SSS is assigned or configured is referred to as a PSS / SSS symbol / subcarrier / RE, respectively.

In the present invention, the CRS port, the UE-RS port, the CSI-RS port, and the TRS port are respectively an antenna port configured to transmit CRS, an antenna port configured to transmit UE-RS, An antenna port configured to transmit CSI-RS and an antenna port configured to transmit TRS. Antenna ports configured to transmit CRSs can be distinguished from each other by the location of REs occupied by the CRS according to the CRS ports, and antenna ports configured to transmit UE-RSs The antenna ports configured to transmit the CSI-RSs can be distinguished from each other by the positions of the REs occupied by the UE-RS according to the -RS ports, and the CSI-RSs occupy The location of the REs can be distinguished from each other. Therefore, the term CRS / UE-RS / CSI-RS / TRS port may be used as a term for a pattern of REs occupied by CRS / UE-RS / CSI-RS / TRS in a certain resource region.

Meanwhile, the 5G communication including the NR system will be described.

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

Some use cases may require multiple areas for optimization, and other use cases may be focused on only one key performance indicator (KPI). 5G supports these various use cases in a flexible and reliable way.

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 may not see dedicated voice services for the first time in the 5G era. In 5G, voice is expected to be treated as an application simply using the data connection provided by the communication system. The main reasons for the increased traffic volume are the increase in content size and the increase in the number of applications requiring high data rates. Streaming services (audio and video), interactive video, and mobile Internet connections will become more popular 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. And, cloud storage is a special use case that drives the growth of uplink data rates. 5G is also used for remote tasks in the cloud and requires much lower end-to-end delays to maintain a good user experience when tactile interfaces are used. Entertainment For example, cloud gaming and video streaming are another key factor in increasing the need for mobile broadband capabilities. Entertainment is essential in smartphones and tablets anywhere, including in 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 amount of data.

In addition, one of the most anticipated 5G use cases relates to the ability to seamlessly connect embedded sensors in all applications, namely mMTC. By 2020, potential IoT devices are expected to reach 20 billion. Industrial IoT is one of the areas where 5G plays a major role in enabling smart cities, asset tracking, smart utilities, agriculture and security infrastructure.

URLLC includes new services that will change the industry through ultra-reliable / low-latency links available, 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, drone control and coordination.

Next, a number of use cases in a 5G communication system including an NR system will be described in more detail.

5G can complement fiber-to-the-home (FTTH) and cable-based broadband (or DOCSIS) as a means of providing streams that are rated at hundreds of megabits per second to gigabits per second. This high speed is required to deliver TVs in 4K and above (6K, 8K and above) resolutions as well as virtual and augmented reality. Virtual Reality (AVR) and Augmented Reality (AR) applications include nearly immersive sporting events. Certain applications may require special network settings. For example, for VR games, game companies may need to integrate core servers with network operator's edge network servers to minimize latency.

Automotive is expected to be an important new driver for 5G, with many examples 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 use case in the automotive field is augmented reality dashboards. It identifies objects in the dark above what the driver sees through the front window and overlays information that tells the driver about the distance and movement of the object. In the future, wireless modules enable communication between vehicles, the exchange of information between the vehicle and the supporting infrastructure, and the exchange of information between the vehicle and other connected devices (eg, devices carried by pedestrians). Safety systems guide alternative courses of action to help drivers drive safer, reducing the risk of an accident. The next step will be a remotely controlled or self-driven vehicle. This is very reliable and requires very fast communication between different self-driving vehicles and between automobiles and infrastructure. In the future, self-driving vehicles will perform all driving activities, and drivers will focus on traffic anomalies that the vehicle itself cannot identify. The technical requirements of self-driving vehicles require ultra-low latency and ultra-fast reliability to increase traffic safety to an unachievable level.

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 hypothesis. Temperature sensors, window and heating controllers, burglar alarms and appliances 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 distributed sensor networks. Smart grids interconnect these sensors using digital information and communication technologies to gather information and act accordingly. This information can include the behavior of suppliers and consumers, allowing smart grids to improve the distribution of fuels such as electricity in efficiency, reliability, economics, sustainability of production, and in an automated manner. 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 may support telemedicine that provides clinical care from a distance. This can help reduce barriers to distance and improve access to healthcare services that are not consistently available in remote rural areas. It is also used to save lives in critical care and emergencies. A mobile communication based wireless sensor network 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 the cables with reconfigurable wireless links is an attractive opportunity in many industries. However, achieving this requires that the wireless connection operates with similar cable delay, reliability, and capacity, and that management is simplified. Low latency and very low error probability are new requirements that need to be connected in 5G.

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

FIG. 1 is a diagram illustrating a control plane and a user plane structure of a radio interface protocol between a terminal and an E-UTRAN based on a 3GPP radio access network standard. The control plane refers to a path through which control messages used by a user equipment (UE) and a network to manage a call are transmitted. The user plane refers to a path through which data generated at an application layer, for example, voice data or Internet packet data, is transmitted.

The physical layer, which is the first layer, provides an information transfer service to an upper layer by using a physical channel. The physical layer is connected to the upper layer of the medium access control layer through a transport channel. Data moves between the medium access control layer and the physical layer through the transmission channel. Data moves between the physical layer between the transmitting side and the receiving side through the physical channel. The physical channel utilizes time and frequency as radio resources. In detail, the physical channel is modulated in an Orthogonal Frequency Division Multiple Access (OFDMA) scheme in downlink, and modulated in a Single Carrier Frequency Division Multiple Access (SC-FDMA) scheme in uplink.

The medium access control (MAC) layer of the second layer provides a service to a radio link control (RLC) layer, which is a higher layer, through a logical channel. The RLC layer of the second layer supports reliable data transmission. The function of the RLC layer may be implemented as a functional block inside the MAC. The Packet Data Convergence Protocol (PDCP) layer of the second layer performs a header compression function to reduce unnecessary control information in order to efficiently transmit IP packets such as IPv4 or IPv6 in a narrow bandwidth wireless interface.

The Radio Resource Control (RRC) layer located at the bottom of the third layer is defined only in the control plane. The RRC layer is responsible for controlling logical channels, transmission channels, and physical channels in connection with configuration, reconfiguration, and release of radio bearers. The radio bearer refers to a service provided by the second layer for data transmission between the terminal and the network. To this end, the RRC layers of the UE and the network exchange RRC messages with each other. If there is an RRC connected (RRC Connected) between the UE and the RRC layer of the network, the UE is in an RRC connected mode, otherwise it is in an RRC idle mode. The non-access stratum (NAS) layer above the RRC layer performs functions such as session management and mobility management.

The downlink transmission channel for transmitting data from the network to the UE includes a broadcast channel (BCH) for transmitting system information, a paging channel (PCH) for transmitting a paging message, and a downlink shared channel (SCH) for transmitting user traffic or a control message. have. Traffic or control messages of a downlink multicast or broadcast service may be transmitted through a downlink SCH or may be transmitted through a separate downlink multicast channel (MCH). The uplink transmission channel for transmitting data from the terminal to the network includes a random access channel (RAC) for transmitting an initial control message and an uplink shared channel (SCH) for transmitting user traffic or a control message. Above the transmission channel, the logical channel mapped to the transmission channel includes a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and an MTCH (multicast). Traffic Channel).

FIG. 2 is a diagram for explaining physical channels used in a 3GPP system and a general signal transmission method using the same.

If the UE is powered on or enters a new cell, the UE performs an initial cell search operation such as synchronizing with the base station (S201). To this end, the terminal may receive a Primary Synchronization Channel (P-SCH) and a Secondary Synchronization Channel (S-SCH) from the base station to synchronize with the base station and obtain information such as a cell ID. have. Thereafter, the terminal may receive a physical broadcast channel from the base station to obtain broadcast information in a cell. Meanwhile, the terminal may receive a downlink reference signal (DL RS) in the initial cell search step to check the downlink channel state.

Upon completion of the initial cell search, the UE acquires more specific system information by receiving a physical downlink control channel (PDSCH) according to a physical downlink control channel (PDCCH) and information on the PDCCH. It may be (S202).

On the other hand, when the first access to the base station or there is no radio resource for signal transmission, the terminal may perform a random access procedure (RACH) for the base station (steps S203 to S206). To this end, the UE may transmit a specific sequence as a preamble through a physical random access channel (PRACH) (S203 and S205), and receive a response message for the preamble through the PDCCH and the corresponding PDSCH ( S204 and S206). In the case of contention-based RACH, a contention resolution procedure may be additionally performed.

After performing the above-described procedure, the UE performs a PDCCH / PDSCH reception (S207) and a physical uplink shared channel (PUSCH) / physical uplink control channel (Physical Uplink) as a general uplink / downlink signal transmission procedure. Control Channel (PUCCH) transmission (S208) may be performed. In particular, the terminal receives downlink control information (DCI) through the PDCCH. Here, the DCI includes control information such as resource allocation information for the terminal, and the format is different according to the purpose of use.

Meanwhile, the control information transmitted by the terminal to the base station through the uplink or received by the terminal from the base station includes a downlink / uplink ACK / NACK signal, a channel quality indicator (CQI), a precoding matrix index (PMI), and a rank indicator (RI). ), And the like. In the 3GPP LTE system, the terminal may transmit the above-described control information such as CQI / PMI / RI through the PUSCH and / or PUCCH.

Meanwhile, the NR system considers a method using a high ultra-high frequency band, that is, a millimeter frequency band of 6 GHz or more, to transmit data while maintaining a high data rate to a large number of users using a wide frequency band. 3GPP uses this as the name NR, which is referred to as NR system in the present invention.

3 illustrates the structure of a radio frame used in NR.

In NR, uplink and downlink transmission are composed of frames. The radio frame has a length of 10 ms and is defined as two 5 ms half-frames (HFs). Half-frames are defined as five 1 ms subframes (SFs). The subframe is divided into one or more slots, and the number of slots in the subframe depends on the subcarrier spacing (SCS). Each slot includes 12 or 14 OFDM (A) symbols according to a cyclic prefix (CP). Usually when CP is used, each slot contains 14 symbols. If extended CP is used, each slot includes 12 symbols. Here, the symbol may include an OFDM symbol (or CP-OFDM symbol), SC-FDMA symbol (or DFT-s-OFDM symbol).

Table 1 exemplarily shows that when the CP is used, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary according to the SCS.

SCS (15 * 2 ^ u)	N slot symb	N frame, u slot	N subframe, u slot
15KHz (u = 0)	14	10	One
30KHz (u = 1)	14	20	2
60KHz (u = 2)	14	40	4
120KHz (u = 3)	14	80	8
240KHz (u = 4)	14	160	16

* N ^slot _symb : Number of symbols in slot * N ^{frame, u} _slot : Number of slots in frame

* N ^{subframe, u} _slot : Number of slots in a ^subframe

Table 2 illustrates that when the extended CP is used, the number of symbols for each slot, the number of slots for each frame, and the number of slots for each subframe vary according to the SCS.

SCS (15 * 2 ^ u)	N slot symb	N frame, u slot	N subframe, u slot
60KHz (u = 2)	12	40	4

In the NR system, OFDM (A) numerology (eg, SCS, CP length, etc.) may be set differently among a plurality of cells merged into one UE. Accordingly, the (absolute time) section of a time resource (eg, SF, slot, or TTI) (commonly referred to as a time unit (TU) for convenience) composed of the same number of symbols may be set differently between merged cells. 4 illustrates a slot structure of an NR frame. The slot includes a plurality of symbols in the time domain. For example, one slot includes seven symbols in the case of a normal CP, but one slot includes six symbols in the case of an extended CP. The carrier includes a plurality of subcarriers in the frequency domain. Resource block (RB) is defined as a plurality of consecutive subcarriers (eg, 12) in the frequency domain. The bandwidth part (BWP) is defined as a plurality of consecutive (P) RBs in the frequency domain and may correspond to one numerology (eg, SCS, CP length, etc.). The carrier may include up to N (eg, 5) BWPs. Data communication is performed through an activated BWP, and only one BWP may be activated by one UE. Each element in the resource grid is referred to as a resource element (RE), one complex symbol may be mapped.

5 illustrates the structure of a self-contained slot. In an NR system, a frame is characterized by a self-complete structure in which a DL control channel, DL or UL data, UL control channel, and the like can be included in one slot. For example, the first N symbols in a slot may be used to transmit a DL control channel (hereinafter DL control region), and the last M symbols in the slot may be used to transmit a UL control channel (hereinafter UL control region). N and M are each an integer of 0 or more. A resource region (hereinafter, referred to as a data region) between the DL control region and the UL control region may be used for DL data transmission or may be used for UL data transmission. As an example, the following configuration may be considered. Each interval is listed in chronological order.

1.DL only configuration

2.UL only configuration

3. Mixed UL-DL Configuration

DL area + Guard Period (GP) + UL control area

DL control area + GP + UL area

DL area: (i) DL data area, (ii) DL control area + DL data area

UL region: (i) UL data region, (ii) UL data region + UL control region

The PDCCH may be transmitted in the DL control region, and the PDSCH may be transmitted in the DL data region. PUCCH may be transmitted in the UL control region, and PUSCH may be transmitted in the UL data region. Downlink control information (DCI), for example, DL data scheduling information, UL data scheduling information, and the like may be transmitted in the PDCCH. In PUCCH, uplink control information (UCI), for example, positive acknowledgment / negative acknowledgment (ACK / NACK) information, channel state information (CSI) information, and scheduling request (SR) for DL data may be transmitted. The GP provides a time gap in the process of the base station and the terminal switching from the transmission mode to the reception mode or from the reception mode to the transmission mode. Some symbols at the time of switching from DL to UL in the subframe may be set to GP.

6 illustrates SSB transmission. The UE may perform cell search, system information acquisition, beam alignment for initial access, DL measurement, etc. based on the SSB. SSB is mixed with a Synchronization Signal / Physical Broadcast channel (SS / PBCH) block.

Referring to FIG. 6, the SSB is periodically transmitted in accordance with the SSB period. The SSB basic period assumed by the UE in initial cell search is defined as 20 ms. After cell access, the SSB period may be set to one of {5ms, 10ms, 20ms, 40ms, 80ms, 160ms} by a network (eg, a base station). A set of SSB bursts is constructed at the beginning of the SSB period. The SSB burst set consists of a 5ms time window (ie, half-frame), and the SSB can be transmitted up to L times within the SS burst set. The maximum number of transmissions L of the SSB may be given as follows according to the frequency band of the carrier wave. One slot includes up to two SSBs.

-For frequency range up to 3 GHz, L = 4

-For frequency range from 3 GHz to 6 GHz, L = 8

-For frequency range from 6 GHz to 52.6 GHz, L = 64

The time position of the SSB candidate in the SS burst set may be defined as follows according to the SCS. The temporal position of the SSB candidate is indexed from 0 to L-1 in time order within the SSB burst set (ie, half-frame) (SSB index).

Case A-15 kHz SCS: The index of the start symbol of the candidate SSB is given by {2, 8} + 14 * n. N = 0, 1 when the carrier frequency is 3 GHz or less. N = 0, 1, 2, and 3 when the carrier frequency is 3 GHz to 6 GHz.

Case B-30 kHz SCS: The index of the start symbol of the candidate SSB is given by {4, 8, 16, 20} + 28 * n. N = 0 when the carrier frequency is 3 GHz or less. N = 0, 1 when the carrier frequency is 3 GHz to 6 GHz.

Case C-30 kHz SCS: The index of the start symbol of the candidate SSB is given by {2, 8} + 14 * n. N = 0, 1 when the carrier frequency is 3 GHz or less. N = 0, 1, 2, and 3 when the carrier frequency is 3 GHz to 6 GHz.

Case D-120 kHz SCS: The index of the start symbol of the candidate SSB is given by {4, 8, 16, 20} + 28 * n. If the carrier frequency is greater than 6 GHz, then n = 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18.

Case E-240 kHz SCS: The index of the start symbol of the candidate SSB is given by {8, 12, 16, 20, 32, 36, 40, 44} + 56 * n. If the carrier frequency is greater than 6 GHz, then n = 0, 1, 2, 3, 5, 6, 7, 8.

7 illustrates multi-beam transmission of the SSB.

Beam sweeping means that the Transmission Reception Point (TRP) (eg, base station / cell) varies the beam (direction) of the radio signal over time (hereinafter, the beam and beam direction may be mixed). Referring to FIG. 8, the SSB may be periodically transmitted using beam sweeping. In this case, the SSB index is implicitly linked with the SSB beam. The SSB beam may be changed in units of SSB (index) or in units of SSB (index) group. In the latter case, the SSB beam remains the same within the SSB (index) group. That is, the transmission beam reflections of the SSB are repeated in a plurality of consecutive SSBs. The maximum number of transmissions L of the SSB in the SSB burst set has a value of 4, 8 or 64 depending on the frequency band to which the carrier belongs. Accordingly, the maximum number of SSB beams in the SSB burst set may also be given as follows according to the frequency band of the carrier.

-For frequency range up to 3 GHz, Max number of beams = 4

-For frequency range from 3 GHz to 6 GHz, Max number of beams = 8

-For frequency range from 6 GHz to 52.6 GHz, Max number of beams = 64

However, when multi-beam transmission is not applied, the number of SSB beams is one.

When the terminal attempts to initially access the base station, the terminal may align the beam with the base station based on the SSB. For example, the terminal identifies the best SSB after performing SSB detection. Thereafter, the terminal may transmit the RACH preamble to the base station using the PRACH resources linked / corresponding to the index (ie, beam) of the best SSB. SSB may be used to align the beam between the base station and the terminal even after the initial access.

8 illustrates a method of notifying the SSB (SSB_tx) that is actually transmitted.

Up to L SSBs may be transmitted in the SSB burst set, and the number / locations of the SSBs actually transmitted may vary by base station / cell. The number / location at which the SSB is actually transmitted is used for rate-matching and measurement, and information about the SSB actually transmitted is indicated as follows.

In the case of rate-matching: it may be indicated through UE-specific RRC signaling or RMSI. UE-specific RRC signaling includes a full (eg, length L) bitmap in both the below 6 GHz and above 6 GHz frequency ranges. On the other hand, the RMSI includes a full bitmap below 6GHz and a compressed bitmap as shown above. Specifically, information about the SSB actually transmitted using the group-bit map (8 bits) + the intra-group bitmap (8 bits) can be indicated. Here, resources indicated by UE-specific RRC signaling or RMSI (eg, RE) may be reserved for SSB transmission, and PDSCH / PUSCH and the like may be rate-matched in consideration of SSB resources.

In the case of measurement: When in the RRC connected mode, the network (eg, base station) may indicate the set of SSBs to be measured within the measurement interval. The SSB set may be indicated for each frequency layer. If there is no indication about the SSB set, the default SSB set is used. The default SSB set includes all SSBs within the measurement interval. The SSB set may be indicated using a full (eg, length L) bitmap of RRC signaling. When in RRC idle mode, a default set of SSBs is used.

Meanwhile, in the NR system, a massive multiple input multiple output (MIMO) environment in which a transmit / receive antenna is greatly increased may be considered. That is, as a large MIMO environment is considered, the number of transmit / receive antennas may increase to tens or hundreds or more. On the other hand, the NR system supports communication in the above 6GHz band, that is, the millimeter frequency band. However, the millimeter frequency band has a frequency characteristic that the signal attenuation with the distance is very rapid due to the use of a frequency band too high. Therefore, NR systems using bands of at least 6 GHz or more use a beamforming technique that collects and transmits energy in a specific direction rather than omnidirectionally to compensate for a sudden propagation attenuation characteristic. In large MIMO environments, beamforming weight vectors / precoding vectors are used to reduce the complexity of hardware implementation, increase performance with multiple antennas, flexibility in resource allocation, and ease of frequency-specific beam control. According to the application position, a hybrid beamforming technique in which an analog beamforming technique and a digital beamforming technique are combined is required.

9 is a diagram illustrating an example of a block diagram of a transmitting end and a receiving end for hybrid beamforming.

As a method for forming a narrow beam in the millimeter frequency band, a beamforming method of increasing energy only in a specific direction by transmitting the same signal using a phase difference appropriate to a large number of antennas in a BS or a UE is mainly considered. Such beamforming methods include digital beamforming that creates a phase difference in a digital baseband signal, analog beamforming that uses a time delay (ie, cyclic shift) in a modulated analog signal to create a phase difference, digital beamforming, and an analog beam. Hybrid beamforming using both the forming and the like. If an RF unit (or transceiver unit (TXRU)) is provided to enable transmission power and phase adjustment for each antenna element, independent beamforming is possible for each frequency resource. However, there is a problem in that it is ineffective in installing an RF unit in all 100 antenna elements. In other words, the millimeter frequency band should be used by a large number of antennas to compensate for rapid propagation attenuation, and digital beamforming is equivalent to the number of antennas, so RF components (eg, digital-to-analog converters (DACs), mixers, power Since an amplifier (power amplifier, linear amplifier, etc.) is required, there is a problem in that the cost of a communication device increases in order to implement digital beamforming in the millimeter frequency band. Therefore, when a large number of antennas are required, such as the millimeter frequency band, the use of analog beamforming or hybrid beamforming is considered. The analog beamforming method maps a plurality of antenna elements to one TXRU and adjusts the beam direction with an analog phase shifter. Such an analog beamforming method has a disadvantage in that only one beam direction can be made in the entire band and thus frequency selective beamforming (BF) cannot be performed. Hybrid BF is an intermediate form between digital BF and analog BF with B RF units less than Q antenna elements. In the case of the hybrid BF, although there are differences depending on the connection method of the B RF units and the Q antenna elements, the direction of beams that can be simultaneously transmitted is limited to B or less.

Downlink Beam Management (DL BM)

The BM process is a BS (or transmission and reception point (TRP)) and / or set of UE beams that can be used for downlink (DL) and uplink (UL) transmission / reception. As a process for acquiring and maintaining), the following process and terminology may be included.

Beam measurement: an operation in which a BS or a UE measures a characteristic of a received beamforming signal.

Beam determination: an operation in which the BS or the UE selects its Tx beam / Rx beam.

Beam sweeping: an operation of covering the spatial domain using transmit and / or receive beams for a certain time interval in a predetermined manner.

Beam report: an operation in which a UE reports information of a beamformed signal based on beam measurement.

The BM process may be divided into (1) DL BM process using SSB or CSI-RS and (2) UL BM process using SRS (sounding reference signal). In addition, each BM process may include a Tx beam sweeping for determining the Tx beam and an Rx beam sweeping for determining the Rx beam.

In this case, the DL BM process may include (1) transmission of beamformed DL RSs (eg, CSI-RS or SSB) by the BS, and (2) beam reporting by the UE.

Here, the beam report may include a preferred DL RS ID (s) and a reference signal received power (RSRP) corresponding thereto. The DL RS ID may be a SSB Resource Indicator (SSBRI) or a CSI-RS Resource Indicator (CRI).

10 shows an example of beamforming using SSB and CSI-RS.

As shown in FIG. 10, the SSB beam and the CSI-RS beam may be used for beam measurement. The measurement metric is a resource / block RSRP. SSB is used for coarse beam measurement and CSI-RS can be used for fine beam measurement. SSB can be used for both Tx beam sweeping and Rx beam sweeping. Rx beam sweeping using the SSB may be performed by attempting to receive the SSB while the UE changes the Rx beam for the same SSBRI across multiple SSB bursts. Here, one SS burst includes one or more SSBs, and one SS burst set includes one or more SSB bursts.

1. DL BM using SSB

11 is a flowchart illustrating an example of a DL BM process using an SSB.

The beam report setting using the SSB is performed at the channel state information (CSI) / beam setting in RRC_CONNECTED.

-The UE receives the CSI-ResourceConfig IE including the CSI-SSB-ResourceSetList for the SSB resources used for the BM from the BS (S1110). The RRC parameter csi-SSB-ResourceSetList represents a list of SSB resources used for beam management and reporting in one resource set. Here, the SSB resource set may be set to {SSBx1, SSBx2, SSBx3, SSBx4, 쪋}. SSB index may be defined from 0 to 63.

-The UE receives signals on SSB resources from the BS based on the CSI-SSB-ResourceSetList (S1120).

If the CSI-RS reportConfig related to the report on the SSBRI and reference signal received power (RSRP) is configured, the UE reports the best SSBRI and the corresponding RSRP to the BS (S1130). For example, when reportQuantity of the CSI-RS reportConfig IE is set to 'ssb-Index-RSRP', the UE reports the best SSBRI and the corresponding RSRP to the BS.

When the CSI-RS resource is configured in the same OFDM symbol (s) as the SSB, and the 'QCL-TypeD' is applicable, the UE is similarly co-located in terms of the 'QCL-TypeD' with the CSI-RS and the SSB ( quasi co-located (QCL). In this case, QCL-TypeD may mean that QCLs are interposed between antenna ports in terms of spatial Rx parameters. The UE may apply the same reception beam when receiving signals of a plurality of DL antenna ports in a QCL-TypeD relationship.

2. DL BM using CSI-RS

Referring to the CSI-RS use, i) CSI-RS is used for beam management when a repetition parameter is set for a specific CSI-RS resource set and TRS_info is not set. ii) If the repeating parameter is not set and TRS_info is set, the CSI-RS is used for a tracking reference signal (TRS). iii) If the repetition parameter is not set and TRS_info is not set, the CSI-RS is used for CSI acquisition.

(RRC parameter) When repetition is set to 'ON', it is associated with the Rx beam sweeping process of the UE. When the repetition is set to 'ON', when the UE receives the NZP-CSI-RS-ResourceSet, the UE receives signals of at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet with the same downlink spatial domain filter. Can be assumed to be transmitted. That is, at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet is transmitted through the same Tx beam. Here, signals of at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet may be transmitted in different OFDM symbols.

On the other hand, the repetition is set to 'OFF' is related to the Tx beam sweeping process of the BS. When the repetition is set to 'OFF', the UE does not assume that signals of at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet are transmitted to the same downlink spatial domain transport filter. That is, signals of at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet are transmitted through different Tx beams. 12 shows another example of a DL BM process using CSI-RS.

FIG. 12 (a) shows the Rx beam determination (or refinement) process of the UE, and FIG. 12 (b) shows the Tx beam sweeping process of the BS. 12A illustrates a case where the repeating parameter is set to 'ON', and FIG. 12B illustrates a case where the repeating parameter is set to 'OFF'.

12 (a) and 13 (a), the process of determining the Rx beam of the UE will be described.

13 (a) is a flowchart illustrating an example of a process of determining a reception beam of a UE.

The UE receives an NZP CSI-RS resource set IE including an RRC parameter related to 'repetition' from the BS through RRC signaling (S1310). Here, the RRC parameter 'repetition' is set to 'ON'.

The UE repeats signals on resource (s) in the CSI-RS resource set in which the RRC parameter 'repetition' is set to 'ON' in different OFDM symbols through the same Tx beam (or DL spatial domain transport filter) of the BS It receives (S1320).

The UE determines its Rx beam (S1330).

The UE omits CSI reporting (S1340). That is, when the mall RRC parameter 'repetition' is set to 'ON', the UE may omit CSI reporting.

12 (b) and 13 (b), the Tx beam determination process of the BS will be described.

13 (b) is a flowchart illustrating an example of a transmission beam determination process of a BS.

The UE receives an NZP CSI-RS resource set IE including an RRC parameter related to 'repetition' from the BS through RRC signaling (S1350). Here, the RRC parameter 'repetition' is set to 'OFF', and is related to the Tx beam sweeping process of the BS.

The UE receives signals on resources in the CSI-RS resource set in which the RRC parameter 'repetition' is set to 'OFF' through different Tx beams (DL spatial domain transmission filter) of the BS (S1360).

The UE selects (or determines) the best beam (S1370).

The UE reports the ID (eg, CRI) and related quality information (eg, RSRP) for the selected beam to the BS (S1380). That is, when the CSI-RS is transmitted for the BM, the UE reports the CRI and its RSRP to the BS.

14 illustrates an example of resource allocation in the time and frequency domain associated with the operation of FIG. 12.

When repetition 'ON' is set in the CSI-RS resource set, a plurality of CSI-RS resources are repeatedly used by applying the same transmission beam, and when repetition 'OFF' is set in the CSI-RS resource set, different CSI-RSs are used. Resources may be transmitted in different transmission beams.

3. Beam indication related to DL BM

The UE may receive a list of at least M candidate transmission configuration indication (TCI) states for at least a quasi co-location (QCL) indication through RRC signaling. Here, M depends on UE (capability) and may be 64.

Each TCI state may be set with one reference signal (RS) set. Table 3 shows an example of the TCI-State IE. The TCI-State IE is associated with one or two DL reference signal (RS) corresponding quasi co-location (QCL) types.

-ASN1START-- TAG-TCI-STATE-STARTTCI-State :: = SEQUENCE {tci-StateId TCI-StateId, qcl-Type1 QCL-Info, qcl-Type2 QCL-Info OPTIONAL,-Need R ...} QCL -Info :: = SEQUENCE {cell ServCellIndex OPTIONAL,-Need R bwp-Id BWP-Id OPTIONAL,-Cond CSI-RS-Indicated referenceSignal CHOICE {csi-rs NZP-CSI-RS-ResourceId, ssb SSB-Index} , qcl-Type ENUMERATED {typeA, typeB, typeC, typeD}, ...}-TAG-TCI-STATE-STOP-- ASN1STOP

In Table 3, 'bwp-Id' indicates the DL BWP where the RS is located, 'cell' indicates the carrier on which the RS is located, and 'referencesignal' indicates the source of pseudo co-location for the target antenna port (s) ( Reference antenna port (s) to be a source or a reference signal including the same. The target antenna port (s) may be CSI-RS, PDCCH DMRS, or PDSCH DMRS.

4.Quasi-Co Location (QCL)

The UE may receive a list containing up to M TCI-status settings for decoding the PDSCH according to the detected PDCCH having an intended DCI for the UE and a given cell. Here, M depends on UE capability.

As illustrated in Table 3, each TCI-State includes parameters for establishing a QCL relationship between one or two DL RSs and a DM-RS port of PDSCH. The QCL relationship is established with the RRC parameters qcl-Type1 for the first DL RS and qcl-Type2 (if set) for the second DL RS.

The QCL type corresponding to each DL RS is given by the parameter 'qcl-Type' in QCL-Info, and can take one of the following values:

'QCL-TypeA': {Doppler shift, Doppler spread, average delay, delay spread}

-'QCL-TypeB': {Doppler shift, Doppler spread}

-'QCL-TypeC': {Doppler shift, average delay}

'QCL-TypeD': {Spatial Rx parameter}

For example, if the target antenna port is a specific NZP CSI-RS, the corresponding NZP CSI-RS antenna ports may be indicated / set as a specific TRS in QCL-Type A view and a specific SSB and QCL in QCL-Type D view. have. The UE receiving this indication / setting receives the corresponding NZP CSI-RS using the Doppler and delay values measured in the QCL-TypeA TRS, and applies the reception beam used to receive the QCL-TypeD SSB to the corresponding NZP CSI-RS reception. can do.

CSI related behavior

In a New Radio (NR) system, the channel state information-reference signal (CSI-RS) is used for time and / or frequency tracking, CSI computation, and reference signal received power (RSRP) computation. And for mobility. Here, the CSI calculation is related to the CSI acquisition, and the RSRP calculation is related to the beam management (BM).

15 is a flowchart illustrating an example of a CSI related process.

In order to perform one of the uses of the CSI-RS as described above, the UE receives configuration information related to the CSI from the BS through RRC signaling (S1501).

The configuration information related to CSI includes information related to CSI-IM (interference management) resources, information related to CSI measurement configuration, information related to CSI resource configuration, and information related to CSI-RS resource. Or CSI report configuration related information.

i) CSI-IM resource related information may include CSI-IM resource information, CSI-IM resource set information, and the like. The CSI-IM resource set is identified by a CSI-IM resource set ID, and one resource set includes at least one CSI-IM resource. Each CSI-IM resource is identified by a CSI-IM resource ID.

ii) CSI resource configuration related information may be represented by CSI-ResourceConfig IE. The CSI resource configuration related information defines a group including at least one of a non zero power (NZP) CSI-RS resource set, a CSI-IM resource set, or a CSI-SSB resource set. That is, the CSI resource setting related information includes a CSI-RS resource set list, and the CSI-RS resource set list includes at least one of an NZP CSI-RS resource set list, a CSI-IM resource set list, or a CSI-SSB resource set list. It may include one. The CSI-RS resource set is identified by a CSI-RS resource set ID, and one resource set includes at least one CSI-RS resource. Each CSI-RS resource is identified by a CSI-RS resource ID.

RRC parameters (eg, a 'repetition' parameter related to BM and a 'trs-Info' parameter related to tracking) indicating the use of the CSI-RS may be set for each NZP CSI-RS resource set.

iii) CSI report configuration related information includes a reportConfigType parameter indicating a time domain behavior and a reportQuantity parameter indicating a CSI related quantity for reporting. . The time domain behavior can be periodic, aperiodic or semi-persistent.

The UE measures the CSI based on the configuration information related to the CSI (S1505). The CSI measurement may include (1) a process of receiving a CSI-RS of a UE (S1503) and (2) a process of computing a CSI through a received CSI-RS (S1507). In CSI-RS, resource element (RE) mapping of CSI-RS resources is set in time and frequency domain by RRC parameter CSI-RS-ResourceMapping.

UE reports the measured CSI to BS (S1509).

1. CSI Measurement

The NR system supports more flexible and dynamic CSI measurement and reporting. Here, the CSI measurement may include a process of receiving a CSI-RS and measuring the received CSI-RS to obtain a CSI.

As the time domain behavior of CSI measurement and reporting, channel measurement (CM) and interference measurement (IM) are supported.

The CSI-IM based IM resource (IMR) of the NR has a design similar to that of the CSI-IM of LTE, and is set independently of zero power (ZP) CSI-RS resources for PDSCH rate matching.

The BS transmits the NZP CSI-RS to the UE on each port of the configured NZP CSI-RS based IMR.

For a channel, if there is no PMI and RI feedback, multiple resources are set in the set, and the BS or the network indicates via DCI a subset of NZP CSI-RS resources for channel measurement and / or interference measurement.

We look at resource settings and resource setting settings in more detail.

1. resource setting

Each CSI resource setting 'CSI-ResourceConfig' includes a setting for S≥1 CSI resource set (given by the RRC parameter csi-RS-ResourceSetList). The CSI resource setting corresponds to the CSI-RS-resourcesetlist. Here, S represents the number of configured CSI-RS resource set. Here, the configuration for the S≥1 CSI resource set includes each CSI resource set including CSI-RS resources (configured as NZP CSI-RS or CSI-IM) and SSB resources used for RSRP calculation.

Each CSI resource setting is located in the DL bandwidth part (BWP) identified by the RRC parameter bwp-id. And all the CSI resource settings linked to the CSI reporting setting have the same DL BWP.

The time domain behavior of the CSI-RS resource in the CSI resource setting included in the CSI-ResourceConfig IE is indicated by the RRC parameter resourceType and may be set to be periodic, aperiodic, or semi-persistent.

One or more CSI resource settings for channel measurement (CM) and interference measurement (IM) are set via RRC signaling. Channel Measurement Resource (CMR) may be NZP CSI-RS for CSI acquisition, and Interference Measurement Resource (IMR) may be NZP CSI-RS for CSI-IM and IM. Here, CSI-IM (or ZP CSI-RS for IM) is mainly used for inter-cell interference measurement. NZP CSI-RS for IM is mainly used for intra-cell interference measurement from multi-user.

The UE may assume that the CSI-RS resource (s) for channel measurement and the CSI-IM / NZP CSI-RS resource (s) for interference measurement configured for one CSI reporting are 'QCL-TypeD' for each resource. .

1. 2. Resource setting configuration

The resource setting may mean a list of resource sets. One reporting setting can be linked to up to three resource settings.

If one resource setting is set, the resource setting (given by the RRC parameter resourcesForChannelMeasurement) is for channel measurement for RSRP calculation.

If two resource settings are set, the first resource setting (given by the RRC parameter resourcesForChannelMeasurement) is for channel measurement and the second resource setting (given by csi-IM-ResourcesForInterference or nzp-CSI-RS -ResourcesForInterference). Is for the interference measurement performed on the CSI-IM or NZP CSI-RS.

If three resource settings are set, the first resource setting (given by resourcesForChannelMeasurement) is for channel measurement, and the second resource setting (given by csi-IM-ResourcesForInterference) is for CSI-IM based interference measurement. For example, the third resource setting (given by nzp-CSI-RS-ResourcesForInterference) is for NZP CSI-RS based interference measurement.

If one resource setting (given by resourcesForChannelMeasurement) is set, the resource setting is for channel measurement for RSRP calculation.

If two resource settings are set, the first resource setting (given by resourcesForChannelMeasurement) is for channel measurement, and the second resource setting (given by RRC parameter csi-IM-ResourcesForInterference) is the interference performed on the CSI-IM. Used for measurement.

1. CSI computation

If interference measurement is performed on the CSI-IM, each CSI-RS resource for channel measurement is associated with the CSI-IM resource by resource in order of the CSI-RS resources and the CSI-IM resources within the corresponding resource set. . The number of CSI-RS resources for channel measurement is equal to the number of CSI-IM resources.

For CSI measurement, the UE assumes the following.

Each NZP CSI-RS port configured for interference measurement corresponds to an interference transport layer.

All interference transport layers of the NZP CSI-RS port for interference measurement take into account the energy per resource element (EPRE) ratio.

Assume another interference signal on the RE (s) of the NZP CSI-RS resource for channel measurement, the NZP CSI-RS resource for interference measurement, or the CSI-IM resource for interference measurement.

2. CSI Reporting

For CSI reporting, the time and frequency the UE can use is controlled by the BS.

For CQI, PMI, CRI, SSBRI, LI, RI, RSRP, the UE is responsible for N≥1 CSI-ReportConfig report settings, M≥1 CSI-ResourceConfig resource settings, and a list of one or two trigger states (aperiodicTriggerStateList and semiPersistentOnPUSCH-TriggerStateList). Receive RRC signaling), provided by < RTI ID = 0.0 > Each trigger state in the aperiodicTriggerStateList contains an associated CSI-ReportConfigs list indicating the channel and optionally resource set IDs for interference. In the semiPersistentOnPUSCH-TriggerStateList, each trigger state contains one associated CSI-ReportConfig.

That is, the UE transmits the CSI report indicated by the CSI-ReportConfigs associated with each CSI-RS resource setting to the BS. For example, as indicated by CSI-ReportConfigs associated with the corresponding CSI-RS resource setting, at least one of CQI, PMI, CRI, SSBRI, LI, RI, and RSRP may be reported. However, if CSI-ReportConfigs associated with the CSI-RS resource setting indicates 'none', the UE may not report CSI or RSRP associated with the CSI-RS resource setting. Meanwhile, the CSI-RS resource setting may include resources for SS / PBCH block.

16 is a view for explaining an implementation example of a terminal and a base station according to the present invention.

Referring to FIG. 16, the base station may transmit a 'ReportQuantity' parameter associated with the SS / PBCH block resource and / or the CSI-RS resource to the terminal through an upper layer (S1601). In other words, the base station may configure 'ReportQuantity' related to the SS / PBCH block resource and / or the CSI-RS resource through the upper layer to the terminal.

Thereafter, the base station may transmit at least one of the SS / PBCH block, the CSI-RS, the PDSCH, and the PDCCH based on the 'ReportQuantity' configuration (S1603). In this case, the UE may receive at least one of the SS / PBCH block, the CSI-RS, the PDSCH, and the PDCCH based on the 'ReportQuantity' set through the same OFDM symbol period. For example, the UE may receive at least one of SS / PBCH block, CSI-RS, PDSCH, and PDCCH in the same OFDM symbol period while performing Rx beam sweeping based on a 'ReportQuantity' configuration. Can be. As another example, the UE performs at least one of SS / PBCH block, CSI-RS, PDSCH, and PDCCH in the same OFDM symbol interval without performing Rx beam sweeping based on a 'ReportQuantity' configuration. Can be received.

A specific embodiment in which the UE receives at least one of the SS / PBCH block, the CSI-RS, the PDSCH, and the PDCCH in the same OFDM symbol period based on the 'ReportQuantity' configuration in step S1603 may be implemented based on the following description. have.

Now, in operation S1603, the UE looks at a specific embodiment of receiving at least one of the SS / PBCH block, the CSI-RS, the PDSCH, and the PDCCH in the same OFDM symbol period based on the 'ReportQuantity' configuration.

CSI-RS resources included in the CSI-RS resource set in which the upper layer parameter “TRS-Info” is set, that is, CSI- for time-frequency tracking. The RS may be redundantly included / used / set only in the CSI resource setting and / or the CSI resource set in which the associated ReportQuantity is “No report (or none)”.

That is, the CSI-RS resource included in the CSI-RS resource set in which the “TRS-Info” is set, the CSI resource setting whose associated ReportQuantity is not “No report (or none)”. ) And / or CSI resource sets are not expected / assumed to be redundantly defined / configured / used.

In other words, the UE is a CSI-RS resource other than the ReportQuantity associated with the CSI-RS resources included in the CSI-RS resource set ("TRS-Info") is set to "No report (or none)" It is not expected or assumed to be transmitted through the same OFDM symbol as the CSI-RS resource included in the resource set.

That is, the UE may include another CSI-RS resource set having a ReportQuantity of “No report (or none) associated with CSI-RS resources included in the CSI-RS resource set for which“ TRS-Info ”is set ( It can be expected / assumed to be transmitted through the same OFDM symbol as the CSI-RS resource included in the resource set).

Meanwhile, when ReportQuantity associated with the configured SS / PBCH block resource is not “no report,” the UE receives over several OFDM symbols (for example, four OFDM symbols) in which the SS / PBCH block is transmitted. No RX beam sweeping and / or RX beam refinement is assumed. In other words, the UE may not change the reception filter during several OFDM symbols (eg, four OFDM symbols) in which the SS / PBCH block is transmitted. In addition, if the ReportQuantity associated with the SS / PBCH block resource is not “no report”, the UE may select a PDSCH and a number of OFDM symbols (eg, four OFDM symbols) in which the SS / PBCH block is transmitted. And / or may assume or expect the PDCCH to be transmitted. On the other hand, if the ReportQuantity associated with the SS / PBCH block resource is “no report”, the UE transmits the PDSCH and / or in the OFDM symbols (eg, four OFDM symbols) in which the SS / PBCH block is transmitted. Or it may not expect / assume that the PDCCH is transmitted.

On the other hand, when ReportQuantity associated with SS / PBCH block resource is “SSBRI”, the UE has a PDSCH and / or PDCCH in an OFDM symbol (eg, 4 OFDM symbols) to which the SS / PBCH block is transmitted. It can be expected or assumed to be sent together. On the other hand, when ReportQuantity associated with SS / PBCH block resource is “no report”, the UE expects / assumed that PDSCH and / or PDCCH are transmitted together in a plurality of OFDM symbols in which SS / PBCH block is transmitted. I never do that. This is because, when ReportQuantity associated with the SS / PBCH block resource is “no report”, the UE may perform receive beam sweeping.

Specifically, in the above-described embodiments, when ReportQuantity associated with the SS / PBCH block resource is “no report”, the UE may perform receive beam sweeping and is associated with the SS / PBCH block resource. If the reported ReportQuantity is 'SSBRI', it is expected that the UE does not perform the reception beam sweep. However, when the SS / PBCH block and the PDSCH and / or PDCCH are received by receiving frequency divisional multiplexing (FDM), when the UE performs the reception beam sweeping, the UE cannot properly receive the PDSCH and / or PDCCH. Therefore, when the PDSCH and / or PDCCH is transmitted by FDM with the SS / PBCH block, a restriction is applied to the reception beam sweeping operation of the terminal so that the terminal can properly receive the PDSCH and / or PDCCH. Meanwhile, 'SSBRI' in the present invention may mean 'ssb-index-RSRP' of ReportQuantity parameter.

Meanwhile, when SS / PBCH block resource is included in CSI resource setting and ReportQuantity associated with the SS / PBCH block resource is “No report”, the UE transmits the SS / PBCH block in OFDM. It may not be expected / assumed that CSI-RS for CSI acquisition and CSI-RS for time-frequency tracking are transmitted via symbols. On the other hand, the CSI-RS resources of the CSI-RS resource set for which repetition is set may be expected or assumed to be transmitted together through OFDM symbols in which the SS / PBCH block is transmitted. In this case, the CSI-RS resource set for which repetition is set may mean CSI-RS for beam management.

When the SS / PBCH block resource is included in the CSI resource setting and the ReportQuantity associated with the SS / PBCH block resource is “No report”, the SS / PBCH block is transmitted through OFDM symbols transmitted. CSI-RS resources of a CSI-RS resource set for which repetition is set may be transmitted together. In this case, the CSI-RS resource set for which repetition is set may mean CSI-RS for beam management. Additionally, when the PDCCH and / or PDSCH are transmitted together in the OFDM symbols in which the SS / PBCH block and the CSI-RS are transmitted, the UE changes the reception beam and / or the reception filter in the OFDM symbols in which the corresponding SS / PBCH block is transmitted. Do not assume / do anything.

17 illustrates an embodiment of a wireless communication device according to an embodiment of the present invention.

The wireless communication device described with reference to FIG. 17 may represent a terminal and / or a base station according to an embodiment of the present invention. However, the wireless communication device of FIG. 17 is not necessarily limited to a terminal and / or a base station according to the present embodiment, and may be replaced with various devices such as a vehicle communication system or device, a wearable device, a laptop, a smart phone, and the like. Can be. More specifically, the apparatus includes 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, an unmanned aerial vehicle (UAV), and artificial intelligence (AI). Modules, Robots, Augmented Reality Devices, Virtual Reality Devices, MTC Devices, IoT Devices, Medical Devices, Fintech Devices (or Financial Devices), Security Devices, Climate / Environmental Devices or Other Fourth Industrial Revolution Sector or device associated with a 5G service. For example, a drone may be a vehicle in which humans fly by radio control signals. For example, the MTC device and the IoT device are devices that do not require human intervention or manipulation, and may be smart meters, bending machines, thermometers, smart bulbs, door locks, various sensors, and the like. For example, a medical device is a device used to examine, replace, or modify a device, structure, or function used for diagnosing, treating, alleviating, treating, or preventing a disease, such as a medical device, a surgical device, ( In vitro) diagnostic devices, hearing aids, surgical devices, and the like. For example, the security device is a device installed to prevent a risk that may occur and maintain safety, and may be a camera, a CCTV, a black box, or the like. For example, the fintech device is a device that can provide financial services such as mobile payment, and may be a payment device or a point of sales (POS). For example, the climate / environmental device may mean a device for monitoring and predicting the climate / environment.

In addition, the transmitting terminal and the receiving terminal are mobile phones, smart phones, laptop computers, digital broadcasting terminals, personal digital assistants, portable multimedia players, navigation, slate PCs. , Tablet PCs, ultrabooks, wearable devices, such as smartwatches, glass glasses, head mounted displays, and foldables foldable) devices and the like. For example, the HMD is a display device of a type worn on the head and may be used to implement VR or AR.

Referring to FIG. 17, a terminal and / or a base station according to an embodiment of the present invention may include at least one processor 10 such as a digital signal processor (DSP) or a microprocessor, a transceiver 35, Power management module 5, antenna 40, battery 55, display 15, keypad 20, memory 30, subscriber identity module (SIM) card 25, speaker 45 and microphone ( 50) and the like. In addition, the terminal and / or the base station may include a single antenna or multiple antennas. Meanwhile, the transceiver 35 may also be referred to as a radio frequency module (RF module).

The processor 10 may be configured to implement the functions, procedures, and / or methods described in FIGS. 1-16. In at least some of the embodiments described in FIGS. 1-16, the processor 10 may implement one or more protocols, such as layers of a radio interface protocol (eg, functional layers).

The memory 30 is connected to the processor 10 and stores information related to the operation of the processor 10. The memory 30 may be located inside or outside the processor 10 and may be connected to the processor through various technologies such as wired or wireless communication.

The user may enter various types of information (eg, indication information such as a telephone number) by various techniques such as pressing a button on the keypad 20 or voice activation using the microphone 50. The processor 10 performs appropriate functions such as receiving and / or processing the user's information and dialing the telephone number.

It is also possible to retrieve data (eg, operation data) from the SIM card 25 or the memory 30 to perform the appropriate functions. In addition, the processor 10 may receive and process GPS information from a GPS chip to obtain location information of a terminal and / or a base station such as a vehicle navigation and a map service, or perform a function related to the location information. In addition, the processor 10 may display these various types of information and data on the display 15 for the user's reference and convenience.

The transceiver 35 is connected to the processor 10 to transmit and / or receive a radio signal such as a radio frequency (RF) signal. In this case, the processor 10 may control the transceiver 35 to initiate communication and transmit a radio signal including various types of information or data such as voice communication data. Transceiver 35 may include a receiver for receiving wireless signals and a transmitter for transmitting. Antenna 40 facilitates the transmission and reception of wireless signals. In some embodiments, upon receiving a wireless signal, the transceiver 35 may forward and convert the signal to a baseband frequency for processing by the processor 10. The processed signal may be processed according to various techniques, such as being converted into audible or readable information, and such a signal may be output through the speaker 45.

In some embodiments, the sensor may also be connected to the processor 10. The sensor may include one or more sensing devices configured to detect various types of information including speed, acceleration, light, vibration, and the like. The processor 10 receives and processes sensor information obtained from a sensor such as proximity, location, and image, thereby performing various functions such as collision avoidance and autonomous driving.

Meanwhile, various components such as a camera and a USB port may be additionally included in the terminal and / or the base station. For example, a camera may be further connected to the processor 10, and such a camera may be used for various services such as autonomous driving, vehicle safety service, and the like.

As such, FIG. 17 is only an embodiment of devices configuring a terminal and / or a base station, but is not limited thereto. For example, some components, such as keypad 20, global positioning system (GPS) chip, sensor, speaker 45, and / or microphone 50 may be excluded for terminal and / or base station implementation in some embodiments. It may be.

Specifically, to implement the embodiments of the present disclosure, the operation of the wireless communication apparatus illustrated in FIG. 17 is a terminal according to an embodiment of the present disclosure. When the wireless communication device is a terminal according to an embodiment of the present invention, the processor 10 may receive a 'ReportQuantity' parameter associated with an SS / PBCH block resource and / or a CSI-RS resource from a base station through a higher layer. 35 can be controlled. In other words, the processor 10 may be configured with 'ReportQuantity' associated with the SS / PBCH block resource and / or the CSI-RS resource through the upper layer.

Thereafter, the processor 10 may control the transceiver 35 to receive at least one of the SS / PBCH block, the CSI-RS, the PDSCH, and the PDCCH based on the 'ReportQuantity' configuration through the same OFDM symbol period. have. For example, the processor 10 performs Rx beam sweeping based on a 'ReportQuantity' configuration while at least one of an SS / PBCH block, a CSI-RS, a PDSCH, and a PDCCH in the same OFDM symbol period. Transceiver 35 can be controlled to receive. As another example, the processor 10 may perform an Rx beam sweeping based on a 'ReportQuantity' configuration, and among the SS / PBCH blocks, the CSI-RS, the PDSCH, and the PDCCH in the same OFDM symbol period. The transceiver 35 may be controlled to receive at least one. Meanwhile, a specific embodiment of the processor 10 receiving at least one of the SS / PBCH block, the CSI-RS, the PDSCH, and the PDCCH in the same OFDM symbol period based on the 'ReportQuantity' configuration is based on the above-described embodiments. Can be implemented.

Meanwhile, in order to implement the embodiments of the present invention, when the wireless communication device represented in FIG. 17 is a base station according to the embodiment of the present invention, the processor 10 may perform SS / PBCH block resource and / or through an upper layer. The transceiver 35 may be controlled to transmit a 'ReportQuantity' parameter associated with the CSI-RS resource to the terminal. In other words, the processor 10 may control to configure 'ReportQuantity' related to the SS / PBCH block resource and / or the CSI-RS resource to the terminal through an upper layer.

Thereafter, the processor 10 may control the transceiver 35 to transmit at least one of the SS / PBCH block, the CSI-RS, the PDSCH, and the PDCCH based on the 'ReportQuantity' configuration. have. For example, the processor 10 expects the UE to perform Rx beam sweeping based on the 'ReportQuantity' configuration, while SS / PBCH block, CSI-RS, PDSCH in the same OFDM symbol period. And the transceiver 35 to transmit at least one of the PDCCH. In another example, the processor 10 expects not to perform Rx beam sweeping based on a 'ReportQuantity' configuration, and the SS / PBCH block, CSI-RS, PDSCH and The transceiver 35 may be controlled to transmit at least one of the PDCCHs. In this case, a specific embodiment of controlling the processor 10 to transmit at least one of the SS / PBCH block, the CSI-RS, the PDSCH, and the PDCCH in the same OFDM symbol period based on the 'ReportQuantity' configuration is described above. It can be implemented based on.

The embodiments described above are the components and features of the present invention are combined in a predetermined form. Each component or feature is to be considered optional unless stated otherwise. Each component or feature may be embodied in a form that is not combined with other components or features. It is also possible to combine some of the components and / or features to form an embodiment of the invention. The order of the operations described in the embodiments of the present invention may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment. It is obvious that the claims may be combined to form an embodiment by combining claims that do not have an explicit citation relationship in the claims or as new claims by post-application correction.

Certain operations described in this document as being performed by a base station may in some cases be performed by an upper node thereof. That is, it is obvious that various operations performed for communication with the terminal in a network including a plurality of network nodes including a base station may be performed by the base station or other network nodes other than the base station. A base station may be replaced by terms such as a fixed station, a Node B, an eNode B (eNB), an access point, and the like.

Embodiments according to the present invention may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. In the case of a hardware implementation, an embodiment of the present invention may include 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 invention may be implemented in the form of a module, procedure, function, etc. that performs the functions or operations described above. The software code may be stored in a memory unit and driven by a processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various known means.

It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit of the invention. Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

The method for transmitting and receiving a downlink signal as described above and an apparatus therefor have been described with reference to the example applied to the fifth generation NewRAT system, but it is possible to apply to various wireless communication systems in addition to the fifth generation NewRAT system.

Claims (17)

1. In the wireless communication system, a method for receiving a downlink signal by the terminal,

   Receive measurement report configuration information associated with a resource for a SS / PBCH (Synchronization Signal / Physical Broadcast Channel) block,

   Receive the SS / PBCH block through a plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols,

   Receiving the downlink signal through the plurality of OFDM symbols based on the measurement report configuration information;

   Downlink signal receiving method.
2. The method of claim 1,

   When the measurement report configuration information indicates that the measurement of the SS / PBCH block (measurement) is not reported, the downlink signal is not received,

   Downlink signal receiving method.
3. The method of claim 1,

   When the measurement report configuration information informs the RSRP (Reference Signal Received Power) report of the SS / PBCH block, the downlink signal is received.

   Downlink signal receiving method.
4. The method of claim 1,

   Resources for the SS / PBCH block is included in a specific CSI resource setting,

   Downlink signal receiving method.
5. The method of claim 1,

   The downlink signal is at least one of a physical downlink shared channel (PDSCH) and a physical downlink control channel (PDCCH).

   Downlink signal receiving method.
6. The method of claim 1,

   Informing that the measurement report configuration information does not report measurement of the SS / PBCH block, and when the downlink signal is CSI-RS (Channel State Information-Reference Signal) for beam management, the downlink signal Is received,

   Downlink signal receiving method.
7. The method of claim 1,

   The terminal is capable of communicating with at least one of a terminal, a network, a base station, and an autonomous vehicle other than the terminal,

   Downlink signal receiving method.
8. In a wireless communication system, an apparatus for receiving a downlink signal,

   At least one processor; And

   At least one memory operatively coupled to the at least one processor and storing instructions that, when executed by the at least one processor, cause the at least one processor to perform a particular operation; and ,

   The specific action,

   Receive measurement report configuration information associated with a resource for a SS / PBCH (Synchronization Signal / Physical Broadcast Channel) block,

   Receive the SS / PBCH block through a plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols,

   Receiving the downlink signal through the plurality of OFDM symbols based on the measurement report configuration information;

   Device.
9. The method of claim 8,

   When the measurement report configuration information indicates that the measurement of the SS / PBCH block (measurement) is not reported, the downlink signal is not received,

   Device.
10. The method of claim 8,

    When the measurement report configuration information informs the RSRP (Reference Signal Received Power) report of the SS / PBCH block, the downlink signal is received.

    Device.
11. The method of claim 8,

    Resources for the SS / PBCH block is included in a specific CSI resource setting,

    Device.
12. The method of claim 8,

    The downlink signal is at least one of a physical downlink shared channel (PDSCH) and a physical downlink control channel (PDCCH).

    Device.
13. The method of claim 8,

    Informing that the measurement report configuration information does not report measurement of the SS / PBCH block, and when the downlink signal is CSI-RS (Channel State Information-Reference Signal) for beam management, the downlink signal Is received,

    Device.
14. The method of claim 8,

    The device is capable of communicating with at least one of a terminal, a network, a base station and an autonomous vehicle other than the device,

    Device.
15. In a wireless communication system, a terminal for receiving a downlink signal,

    At least one transceiver;

    At least one processor; And

    At least one memory operatively coupled to the at least one processor and storing instructions that, when executed by the at least one processor, cause the at least one processor to perform a particular operation; and ,

    The specific action,

    Receiving measurement report configuration information associated with a resource for a Synchronization Signal / Physical Broadcast Channel (SS / PBCH) block through the at least one transceiver,

    Receive the SS / PBCH block through a plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols via the at least one transceiver,

    Receiving the downlink signal through the plurality of OFDM symbols based on the measurement report configuration information through the at least one transceiver;

    Terminal.
16. In a wireless communication system, the base station transmits a downlink signal,

    Transmit measurement report configuration information associated with a resource for a SS / PBCH (Synchronization Signal / Physical Broadcast Channel) block,

    Transmit the SS / PBCH block through a plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols,

    Transmitting the downlink signal through the plurality of OFDM symbols based on the measurement report configuration information;

    Downlink signal transmission method.
17. In a wireless communication system, a base station for transmitting a downlink signal,

    At least one transceiver;

    At least one processor; And

    At least one memory operatively coupled to the at least one processor and storing instructions that, when executed by the at least one processor, cause the at least one processor to perform a particular operation; and ,

    The specific action,

    Transmitting measurement report configuration information associated with a resource for a synchronization signal / physical broadcast channel (SS / PBCH) block through the at least one transceiver,

    Transmit the SS / PBCH block through a plurality of Orthogonal Frequency Divisional Multiplexing (OFDM) symbols through the at least one transceiver,

    Transmitting the downlink signal through the plurality of OFDM symbols based on the measurement report configuration information through the at least one transceiver;

    Base station.

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