WO2025135527A1 - Method performed by terminal or base station in wireless communication system, and device therefor - Google Patents

Abstract

A method performed by a terminal, according to at least one from among embodiments disclosed in the present specification, comprises: receiving a CSI-RS configuration through higher layer signaling; receiving a CSI-RS on the basis of the CSI-RS configuration; and acquiring CSI on the basis of the CSI-RS, wherein the CSI-RS is provided through P antenna ports, P is an integer that is greater than 32 but does not exceed 128, the CSI-RS configuration includes a configuration for a plurality of CSI-RS resources related to the P antenna ports, the configuration for the plurality of CSI-RS resources includes information about a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped, on the basis of the slot offset value, within a time interval corresponding to T slots.

Description

Method performed by a terminal or base station in a wireless communication system and device therefor

The present disclosure relates to a wireless communication system, and more specifically, to a method for transmitting and receiving uplink/downlink signals by a terminal or a base station in a wireless communication system and a device therefor.

Wireless communication systems are being widely deployed to provide various types of communication services such as voice and data. In general, wireless communication systems are multiple access systems that can support communication with multiple users by sharing available system resources (bandwidth, transmission power, etc.). Examples of multiple access systems include CDMA (code division multiple access) systems, FDMA (frequency division multiple access) systems, TDMA (time division multiple access) systems, OFDMA (orthogonal frequency division multiple access) systems, and SC-FDMA (single carrier frequency division multiple access) systems.

In NR Rel.15-18, up to 32-Tx port CSI-RS transmission is supported, and CSI-RS resources can be mapped to even PRB or odd PRB in the frequency domain to reduce density.

The technical problem to be achieved is to provide a method for accurately and efficiently performing a wireless signal transmission and reception process and a device therefor. According to one embodiment, a method for transmitting and receiving CSI-RS based on more than 32 ports and a terminal/base station therefor can be provided.

Additional technical challenges can be inferred from the description below.

According to one aspect of the present disclosure, a method performed by a terminal includes: receiving a CSI-RS (channel state information - reference signal) configuration through higher layer signaling; receiving a CSI-RS based on the CSI-RS configuration; and acquiring CSI based on the CSI-RS, wherein the CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, and the CSI-RS configuration includes configurations for a plurality of CSI-RS resources related to the P antenna ports, the configurations for the plurality of CSI-RS resources include information on a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

The above T slots can be two consecutive slots.

The above P can be 64 or 128.

Each CSI-RS resource can be mapped to one of the two slots based on the slot offset value.

The CSI can be acquired based on the aggregation of CSI-RS resources mapped to the first slot among the above two slots and CSI-RS resources mapped to the second slot.

The above slot offset value can be 0 or 1.

The density of the CSI-RS, which is determined based on the number P of antenna ports for the CSI-RS, the number of REs (resource elements) and the number of RBs (resource blocks), may be 0.5.

Each CSI-RS resource can be mapped to either an even physical resource block (PRB) or an odd PRB in the frequency domain.

Among the plurality of CSI-RS resources, a first CSI-RS resource may be mapped to an even PRB of a first slot among the T slots, and a second CSI-RS resource may be mapped to an odd PRB of a second slot among the T slots.

The above terminal may not expect that the above multiple CSI-RS resources will collide with other signals having higher priority than the CSI-RS.

The above CSI-RS may be aperiodic CSI-RS.

According to another aspect of the present disclosure, a non-transitory computer-readable recording medium having recorded thereon instructions for performing the method described above may be provided.

According to another aspect of the present disclosure, a device includes a memory that stores instructions; and a processor that performs operations by executing the instructions, wherein the operations of the processor include receiving a CSI-RS (channel state information - reference signal) configuration through higher layer signaling; receiving a CSI-RS based on the CSI-RS configuration; and acquiring CSI based on the CSI-RS, wherein the CSI-RS is provided through P antenna ports, and P is an integer greater than 32 and not exceeding 128, the CSI-RS configuration includes a configuration for a plurality of CSI-RS resources related to the P antenna ports, the configuration for the plurality of CSI-RS resources includes information on a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

The above device may further include a transceiver.

The above device may be a terminal operating in a wireless communication system.

The above device may be a processing device configured to control a terminal operating in a wireless communication system.

According to another aspect of the present disclosure, a method performed by a base station includes transmitting a CSI-RS (channel state information - reference signal) configuration to a terminal through higher layer signaling; transmitting a CSI-RS to the terminal based on the CSI-RS configuration; and receiving a CSI report from the terminal, wherein the CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, the CSI-RS configuration includes configurations for a plurality of CSI-RS resources related to the P antenna ports, the configurations for the plurality of CSI-RS resources include information on a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

According to another aspect of the present disclosure, a base station includes a memory that stores commands; and a processor that performs operations by executing the commands, wherein the operations of the processor include transmitting a CSI-RS (channel state information - reference signal) configuration to a terminal through higher layer signaling; transmitting a CSI-RS to the terminal based on the CSI-RS configuration; and receiving a CSI report from the terminal, wherein the CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, and the CSI-RS configuration includes configurations for a plurality of CSI-RS resources related to the P antenna ports, and the configurations for the plurality of CSI-RS resources include information on a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

According to at least one of the disclosed embodiments, a wireless signal transmission and reception process can be performed accurately and efficiently. According to one embodiment, by supporting up to 128 CSI-RS ports, system throughput can be improved, and overhead increase due to an increase in the number of CSI-RS ports can be alleviated by distributing and mapping CSI-RS resources to aggregated multiple slots in the time domain.

Additional effects can be inferred from the description below.

Figure 1 illustrates physical channels used in a 3GPP system, which is an example of a wireless communication system, and a general signal transmission method using the channels.

Figure 2 illustrates the structure of a radio frame.

Figure 3 illustrates a resource grid of a slot.

Figure 4 illustrates an example of how physical channels are mapped within slots.

Figure 5 illustrates the PDSCH and ACK/NACK transmission process.

Figure 6 illustrates the PUSCH transmission process.

Figure 7 shows an example of a CSI-related procedure.

Figure 8 illustrates a multi-TRP transmission.

Figure 9 illustrates CSI-RS mapped based on FDM/TDM/CDM in this way.

Figure 10 illustrates a CDM-16 pattern according to one embodiment.

Figures 11 and 12 illustrate examples of CSI-RS mapping for time domain density reduction according to one embodiment.

FIGS. 13 to 15 illustrate examples of CSI-RS mapping for frequency domain density reduction according to one embodiment.

FIGS. 16 and 17 are diagrams each illustrating indexing of CSI-RS ports according to one embodiment.

Figure 18 illustrates an example of a 32 port CSI-RS configuration.

Figure 19 is an example of aggregating two legacy 32 port CSI-RSs to form a 64 port CSI-RS and port indexing.

Figure 20 shows examples of operation procedures of a base station and a terminal according to one embodiment.

FIG. 21 illustrates a flow of a method performed by a terminal according to one embodiment.

FIG. 22 illustrates a flow of a method performed by a base station according to one embodiment.

Figures 23 to 26 illustrate communication systems (1) and wireless devices applicable to various embodiments.

The following technology can be used in various wireless access systems, such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), and SC-FDMA (single carrier frequency division multiple access). CDMA can be implemented with radio technologies such as UTRA (Universal Terrestrial Radio Access) or CDMA2000. TDMA can be implemented with radio technologies such as GSM (Global System for Mobile communications)/GPRS (General Packet Radio Service)/EDGE (Enhanced Data Rates for GSM Evolution). OFDMA can be implemented with radio technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (Evolved UTRA). UTRA is a part of UMTS (Universal Mobile Telecommunications System). 3GPP(3rd Generation Partnership Project) LTE(long term evolution) is a part of E-UMTS(Evolved UMTS) that uses E-UTRA, and LTE-A(Advanced) is an evolved version of 3GPP LTE. 3GPP NR(New Radio or New Radio Access Technology) is an evolved version of 3GPP LTE/LTE-A.

As more and more communication devices require greater communication capacity, the need for improved mobile broadband communication compared to the existing RAT (Radio Access Technology) is increasing. In addition, massive MTC (Machine Type Communications), which connects multiple devices and objects to provide various services anytime and anywhere, is also one of the major issues to be considered in next-generation communications. In addition, a communication system design that considers services/terminals that are sensitive to reliability and latency is being discussed. In this way, the introduction of next-generation RAT that considers eMBB (enhanced Mobile BroadBand Communication), massive MTC, URLLC (Ultra-Reliable and Low Latency Communication), etc. is being discussed, and in the present invention, the corresponding technology is conveniently called NR (New Radio or New RAT).

For clarity of explanation, the description will focus on 3GPP NR, but the technical idea of the present invention is not limited thereto.

In this specification, the expression "setting" can be replaced with the expression "configure/configuration", and the two can be used interchangeably. In addition, conditional expressions (e.g., "if ~~", "in a case ~~" or "when ~~", etc.) can be replaced with the expressions "based on that ~~" or "in a state/status ~~". In addition, the operation of the terminal/base station or the SW/HW configuration according to the satisfaction of the corresponding condition can be inferred/understood. In addition, if the process of the reception (or transmission) side can be inferred/understood from the process of the transmission (or reception) side in signal transmission/reception between wireless communication devices (e.g., base stations, terminals), the description thereof can be omitted. For example, signal determination/generation/encoding/transmission, etc. of the transmission side can be understood as signal monitoring reception/decoding/determination, etc. of the reception side. In addition, the expression that the terminal performs (or does not perform) a specific operation can also be interpreted as the base station expects/assumes (or expects/assumes that the terminal does not perform) the specific operation and operates. The expression that the base station performs (or does not perform) the specific operation can also be interpreted as the terminal expects/assumes (or expects/assumes that the base station does not perform) the specific operation and operates. In addition, the division and index of each section, embodiment, example, option, method, plan, etc. in the following description are for the convenience of explanation and should not be interpreted as meaning that each constitutes an independent invention or that each must be implemented individually. In addition, in describing each section, embodiment, example, option, method, plan, etc., if there is no explicitly conflicting/opposing technology, it can be inferred/interpreted that at least some of them can be combined and implemented together, or at least some can be implemented with some of them omitted.

In a wireless communication system, a terminal receives information from a base station through a downlink (DL), and the terminal transmits information to the base station through an uplink (UL). The information transmitted and received by the base station and the terminal includes data and various control information, and various physical channels exist depending on the type/purpose of the information they transmit and receive.

Figure 1 is a drawing for explaining physical channels used in a 3GPP NR system and a general signal transmission method using them.

When a terminal is powered on again from a powered-off state or enters a new cell, the terminal performs an initial cell search operation such as synchronizing with the base station in step S101. To this end, the terminal receives a Synchronization Signal Block (SSB) from the base station. The SSB includes a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). The terminal synchronizes with the base station based on the PSS/SSS and obtains information such as a cell ID. In addition, the terminal can obtain broadcast information within the cell based on the PBCH. Meanwhile, the terminal can receive a Downlink Reference Signal (DL RS) in the initial cell search step to check the downlink channel status.

After completing the initial cell search, the terminal can obtain more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to physical downlink control channel information in step S102.

Thereafter, the terminal may perform a random access procedure such as steps S103 to S106 to complete connection to the base station. To this end, the terminal may transmit a preamble through a physical random access channel (PRACH) (S103) and receive a response message to the preamble through a physical downlink control channel and a physical downlink shared channel corresponding thereto (S104). In the case of contention-based random access, a contention resolution procedure such as transmission of an additional physical random access channel (S105) and reception of a physical downlink control channel and a physical downlink shared channel corresponding thereto (S106) may be performed.

A terminal that has performed the procedure as described above can then perform physical downlink control channel/physical downlink shared channel reception (S107) and physical uplink shared channel (PUSCH)/physical uplink control channel (PUCCH) transmission (S108) as general uplink/downlink signal transmission procedures. Control information that the terminal transmits to the base station is collectively referred to as uplink control information (UCI). UCI includes HARQ ACK/NACK (Hybrid Automatic Repeat and reQuest Acknowledgement/Negative-ACK), SR (Scheduling Request), CSI (Channel State Information), etc. CSI includes CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indication), etc. UCI is generally transmitted through PUCCH, but can be transmitted through PUSCH when control information and traffic data must be transmitted simultaneously. Additionally, UCI can be transmitted aperiodically via PUSCH upon request/instruction from the network.

Figure 2 illustrates the structure of a radio frame. In NR, uplink and downlink transmissions are organized into frames. Each radio frame has a length of 10 ms and is divided into two 5 ms half-frames (Half-Frames, HF). Each half-frame is divided into five 1 ms subframes (Subframes, SF). A subframe is divided into one or more slots, and the number of slots in a subframe depends on Subcarrier Spacing (SCS). Each slot contains 12 or 14 OFDM (Orthogonal Frequency Division Multiplexing) symbols depending on a CP (cyclic prefix). When a normal CP is used, each slot contains 14 OFDM symbols. When an extended CP is used, each slot contains 12 OFDM symbols.

Table 1 illustrates that when CP is normally used, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary depending on the SCS.

SCS (15*2^u) N ^slot _symb N ^frame,u _slot N ^subframe,u _slot 15KHz (u=0) 14 10 1 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 the slot

* N ^frame,u _slot : Number of slots in a frame

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

Table 2 illustrates that when extended CP is used, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe change depending on the SCS.

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

The structure of the frame is only an example, and the number of subframes, number of slots, and number of symbols in the frame can be changed in various ways.

In an NR system, OFDM numerologies (e.g., SCS) may be set differently between multiple cells merged into one terminal. Accordingly, (absolute time) sections of time resources (e.g., SF, slot or TTI) (conveniently referred to as TU (Time Unit)) consisting of the same number of symbols may be set differently between the merged cells. Here, the symbols may include OFDM symbols (or CP-OFDM symbols), SC-FDMA symbols (or Discrete Fourier Transform-spread-OFDM, DFT-s-OFDM symbols).

Fig. 3 illustrates a resource grid of a slot. A slot includes multiple symbols in the time domain. For example, in the case of a normal CP, one slot includes 14 symbols, but in the case of an extended CP, one slot includes 12 symbols. A carrier includes multiple subcarriers in the frequency domain. An RB (Resource Block) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A BWP (Bandwidth Part) is defined as multiple consecutive PRBs (Physical RBs) in the frequency domain, and can correspond to one numerology (e.g., SCS, CP length, etc.). A carrier can include up to N (e.g., 5) BWPs. Data communication is performed through activated BWPs, and only one BWP can be activated for one terminal. Each element in the resource grid is referred to as a Resource Element (RE), and one complex symbol can be mapped to it.

Fig. 4 illustrates an example of mapping physical channels within a slot. In the DL control region, a PDCCH can be transmitted, and in the DL data region, a PDSCH can be transmitted. In the UL control region, a PUCCH can be transmitted, and in the UL data region, a PUSCH can be transmitted. GP provides a time gap during the process in which a base station and a terminal switch from a transmission mode to a reception mode or from a reception mode to a transmission mode. Some symbols at the time of switching from DL to UL within a subframe can be set to GP.

Below, each physical channel is described in more detail.

PDCCH carries DCI(Downlink Control Information). For example, PDCCH (DCI) carries transmission format and resource allocation of DL-SCH(downlink shared channel), resource allocation information for UL-SCH(uplink shared channel), paging information for PCH(paging channel), system information on DL-SCH, resource allocation information for upper layer control messages such as random access response transmitted on PDSCH, transmission power control command, activation/release of CS(Configured Scheduling), etc. DCI includes CRC(cyclic redundancy check), and CRC is masked/scrambled with various identifiers (e.g., Radio Network Temporary Identifier, RNTI) depending on the owner or usage of PDCCH. For example, if PDCCH is for a specific terminal, CRC is masked with terminal identifier (e.g., Cell-RNTI, C-RNTI). If the PDCCH is for paging, the CRC is masked with the Paging-RNTI (P-RNTI). If the PDCCH is for system information (e.g., System Information Block, SIB), the CRC is masked with the System Information RNTI (SI-RNTI). If the PDCCH is for random access response, the CRC is masked with the Random Access-RNTI (RA-RNTI).

PDCCH is composed of 1, 2, 4, 8, and 16 CCEs (Control Channel Elements) according to AL (Aggregation Level). CCE is a logical allocation unit used to provide PDCCH with a predetermined code rate according to radio channel status. CCE is composed of 6 REGs (Resource Element Groups). REG is defined as one OFDM symbol and one (P)RB. PDCCH is transmitted through CORESET (Control Resource Set). CORESET is defined as a REG set with a given numerology (e.g., SCS, CP length, etc.). Multiple CORESETs for one UE can overlap in the time/frequency domain. CORESET can be configured through system information (e.g., Master Information Block, MIB) or UE-specific upper layer (e.g., Radio Resource Control, RRC, layer) signaling. Specifically, the number of RBs and the number of OFDM symbols (up to 3) constituting the CORESET can be set by upper layer signaling.

For PDCCH reception/detection, the UE monitors PDCCH candidates. The PDCCH candidates represent CCE(s) that the UE should monitor for PDCCH detection. Each PDCCH candidate is defined as 1, 2, 4, 8, or 16 CCEs according to AL. Monitoring includes (blind) decoding the PDCCH candidates. The set of PDCCH candidates that the UE monitors is defined as a PDCCH search space (SS). The search space includes a common search space (CSS) or a UE-specific search space (USS). The UE can acquire DCI by monitoring PDCCH candidates in one or more search spaces set by MIB or higher layer signaling. Each CORESET is associated with one or more search spaces, and each search space is associated with one COREST. The search space can be defined based on the following parameters.

- controlResourceSetId: Indicates the CORESET associated with the search space.

- monitoringSlotPeriodicityAndOffset: Indicates the PDCCH monitoring period (in slots) and the PDCCH monitoring interval offset (in slots).

- monitoringSymbolsWithinSlot: Indicates PDCCH monitoring symbols within the slot (e.g., the first symbol(s) of the CORESET)

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

An occasion (e.g., time/frequency resource) during which PDCCH candidates need to be monitored is defined as a PDCCH (monitoring) opportunity. One or more PDCCH (monitoring) opportunities can be configured within a slot.

Table 3 illustrates the characteristics by search space type.

Type Search Space RNTI Use Case Type0-PDCCH Common SI-RNTI on a primary cell SIB Decoding Type0A-PDCCH Common SI-RNTI on a primary cell SIB Decoding Type1-PDCCH Common RA-RNTI or TC-RNTI on a primary cell Msg2, Msg4 decoding in RACH Type2-PDCCH Common P-RNTI on a primary cell Paging Decoding Type3-PDCCH Common INT-RNTI, SFI-RNTI, TPC-PUSCH-RNTI, TPC-PUCCH-RNTI, TPC-SRS-RNTI, C-RNTI, MCS-C-RNTI, or CS-RNTI(s) UE Specific UE Specific C-RNTI, or MCS-C-RNTI, or CS-RNTI(s) User specific PDSCH decoding

Table 4 shows examples of DCI formats transmitted via PDCCH.

DCI format Usage 0_0 Scheduling of PUSCH in one cell 0_1 Scheduling of PUSCH in one cell 1_0 Scheduling of PDSCH in one cell 1_1 Scheduling of PDSCH in one cell 2_0 Notifying a group of UEs of the slot format 2_1 Notifying a group of UEs of the PRB(s) and OFDM symbol(s) where UE may assume no transmission is intended for the UE 2_2 Transmission of TPC commands for PUCCH and PUSCH 2_3 Transmission of a group of TPC commands for SRS transmissions by one or more UEs

DCI format 0_0 is used to schedule a TB-based (or TB-level) PUSCH, and DCI format 0_1 can be used to schedule a TB-based (or TB-level) PUSCH or a CBG (Code Block Group)-based (or CBG-level) PUSCH. DCI format 1_0 is used to schedule a TB-based (or TB-level) PDSCH, and DCI format 1_1 can be used to schedule a TB-based (or TB-level) PDSCH or a CBG-based (or CBG-level) PDSCH (DL grant DCI). DCI format 0_0/0_1 may be referred to as UL grant DCI or UL scheduling information, and DCI format 1_0/1_1 may be referred to as DL grant DCI or DL scheduling information. DCI format 2_0 is used to convey dynamic slot format information (e.g., dynamic SFI) to the terminal, and DCI format 2_1 is used to convey downlink pre-Emption information to the terminal. DCI format 2_0 and/or DCI format 2_1 can be conveyed to the terminals within a group through a group common PDCCH, which is a PDCCH conveyed to the terminals defined as a group.

DCI format 0_0 and DCI format 1_0 may be referred to as fallback DCI formats, and DCI format 0_1 and DCI format 1_1 may be referred to as non-fallback DCI formats. In the fallback DCI format, the DCI size/field configuration remains the same regardless of the terminal configuration. On the other hand, in the non-fallback DCI format, the DCI size/field configuration changes depending on the terminal configuration.

PDSCH carries downlink data (e.g., DL-SCH transport block, DL-SCH TB), and modulation methods such as Quadrature Phase Shift Keying (QPSK), 16 Quadrature Amplitude Modulation (QAM), 64 QAM, and 256 QAM are applied. TB is encoded to generate a codeword. PDSCH can carry up to two codewords. Scrambling and modulation mapping are performed for each codeword, and modulation symbols generated from each codeword can be mapped to one or more layers. Each layer is mapped to a resource along with a Demodulation Reference Signal (DMRS), generated as an OFDM symbol signal, and transmitted through a corresponding antenna port.

PUCCH carries Uplink Control Information (UCI). UCI includes:

- SR (Scheduling Request): Information used to request UL-SCH resources.

- HARQ(Hybrid Automatic Repeat reQuest)-ACK(Acknowledgement): This is a response to a downlink data packet (e.g., codeword) on the PDSCH. It indicates whether the downlink data packet was successfully received. 1 bit of HARQ-ACK can be transmitted in response to a single codeword, and 2 bits of HARQ-ACK can be transmitted in response to two codewords. The HARQ-ACK response includes positive ACK (simply, ACK), negative ACK (NACK), DTX, or NACK/DTX. Here, HARQ-ACK is used interchangeably with HARQ ACK/NACK and ACK/NACK.

- CSI (Channel State Information): Feedback information for the downlink channel. MIMO (Multiple Input Multiple Output)-related feedback information includes RI (Rank Indicator) and PMI (Precoding Matrix Indicator).

Table 5 shows examples of PUCCH formats. Depending on the PUCCH transmission length, it can be divided into Short PUCCH (format 0, 2) and Long PUCCH (format 1, 3, 4).

PUCCH format Length in OFDM symbols N ^PUCCH _symb Number of bits Usage Etc 0 1 - 2 ≤2 HARQ, SR Sequence selection 1 4 - 14 ≤2 HARQ, [SR] Sequence modulation 2 1 - 2 >2 HARQ, CSI, [SR] CP-OFDM 3 4 - 14 >2 HARQ, CSI, [SR] DFT-s-OFDM
(no UE multiplexing) 4 4 - 14 >2 HARQ, CSI, [SR] DFT-s-OFDM
(Pre DFT OCC)

PUCCH format 0 carries UCI with a maximum size of 2 bits, and is mapped and transmitted based on a sequence. Specifically, the terminal transmits a specific UCI to the base station by transmitting one of a plurality of sequences through PUCCH of PUCCH format 0. The terminal transmits PUCCH of PUCCH format 0 within the PUCCH resource for the corresponding SR configuration only when transmitting a positive SR.

PUCCH format 1 carries UCI of up to 2 bits in size, and modulation symbols are spread in the time domain by an orthogonal cover code (OCC) (which is set differently depending on whether frequency hopping is performed). DMRS is transmitted in symbols where modulation symbols are not transmitted (transmitted by Time Division Multiplexing (TDM)).

PUCCH format 2 carries UCI with a bit size greater than 2 bits, and modulation symbols are transmitted by being frequency-division multiplexed (FDM) with DMRS. DM-RS is located at symbol indices #1, #4, #7, and #10 within a given resource block with a density of 1/3. PN (Pseudo Noise) sequence is used for DM_RS sequence. Frequency hopping can be activated for 2-symbol PUCCH format 2.

PUCCH format 3 does not multiplex terminals within the same physical resource blocks and carries UCI with a bit size greater than 2 bits. In other words, PUCCH resources of PUCCH format 3 do not include orthogonal cover codes. Modulation symbols are transmitted by being time-division multiplexed with DMRS.

PUCCH format 4 supports multiplexing of up to 4 terminals within the same physical resource blocks and carries UCI with a bit size greater than 2 bits. In other words, PUCCH resources of PUCCH format 3 include orthogonal cover codes. Modulation symbols are transmitted by being multiplexed with DMRS and TDM (Time Division Multiplexing).

In a terminal, at least one of one or more cells configured may be configured for PUCCH transmission. At least a primary cell may be configured as a cell for PUCCH transmission. At least one PUCCH cell group may be configured in the terminal based on at least one cell configured for PUCCH transmission, and each PUCCH cell group includes one or more cells. The PUCCH cell group may be simply referred to as a PUCCH group. PUCCH transmission may be configured not only for the primary cell but also for the SCell, and the primary cell belongs to the primary PUCCH group, and the PUCCH-SCell configured for PUCCH transmission belongs to the secondary PUCCH group. For cells belonging to the primary PUCCH group, a PUCCH on the primary cell may be used, and for cells belonging to the secondary PUCCH group, a PUCCH on the PUCCH-SCell may be used.

PUSCH carries uplink data (e.g., UL-SCH transport block, UL-SCH TB) and/or uplink control information (UCI), and is transmitted based on a CP-OFDM (Cyclic Prefix - Orthogonal Frequency Division Multiplexing) waveform or a DFT-s-OFDM (Discrete Fourier Transform - spread - Orthogonal Frequency Division Multiplexing) waveform. When the PUSCH is transmitted based on the DFT-s-OFDM waveform, the UE transmits the PUSCH by applying transform precoding. For example, when transform precoding is disabled (e.g., transform precoding is disabled), the UE transmits the PUSCH based on the CP-OFDM waveform, and when transform precoding is enabled (e.g., transform precoding is enabled), the UE can transmit the PUSCH based on the CP-OFDM waveform or the DFT-s-OFDM waveform. PUSCH transmissions can be dynamically scheduled by UL grant in DCI, or semi-statically scheduled based on higher layer (e.g., RRC) signaling (and/or Layer 1 (L1) signaling (e.g., PDCCH)). PUSCH transmissions can be performed in a codebook-based or non-codebook-based manner.

Fig. 5 illustrates an ACK/NACK transmission process. Referring to Fig. 5, a terminal can detect a PDCCH in slot #n. Here, the PDCCH includes downlink scheduling information (e.g., DCI formats 1_0, 1_1), and the PDCCH indicates a DL assignment-to-PDSCH offset (K0) and a PDSCH-HARQ-ACK reporting offset (K1). For example, the DCI formats 1_0, 1_1 can include the following information:

- Frequency domain resource assignment: Indicates the RB set allocated to PDSCH.

- Time domain resource assignment: K0 (e.g. slot offset), indicates the starting position of PDSCH within slot #n+K0 (e.g. OFDM symbol index), and the length of PDSCH (e.g. number of OFDM symbols).

- PDSCH-to-HARQ_feedback timing indicator: Indicates K1

- HARQ process number (4 bits): Indicates HARQ process ID (Identity) for data (e.g. PDSCH, TB)

- PUCCH resource indicator (PRI): Indicates the PUCCH resource to be used for UCI transmission among multiple PUCCH resources within the PUCCH resource set.

Thereafter, the terminal receives PDSCH from slot #(n+K0) according to the scheduling information of slot #n, and when reception of PDSCH is finished in slot #n1 (where, n+K0≤n1), UCI can be transmitted through PUCCH in slot #(n1+K1). Here, the UCI may include a HARQ-ACK response to the PDSCH. In Fig. 5, it is assumed for convenience that the SCS for the PDSCH and the SCS for the PUCCH are the same and slot# n1 = slot# n+K0, but the present invention is not limited thereto. When the SCSs are different, K1 can be indicated/interpreted based on the SCS of the PUCCH.

When PDSCH is configured to transmit at most 1 TB, HARQ-ACK response may consist of 1 bit. When PDSCH is configured to transmit at most 2 TB, HARQ-ACK response may consist of 2 bits if spatial bundling is not configured, and may consist of 1 bit if spatial bundling is configured. When HARQ-ACK transmission timing for multiple PDSCHs is designated as slot #(n+K1), UCI transmitted in slot #(n+K1) includes HARQ-ACK responses for multiple PDSCHs.

Whether the UE should perform spatial bundling for HARQ-ACK response can be configured (e.g., RRC/higher layer signaling) for each cell group. For example, spatial bundling can be individually configured for each HARQ-ACK response transmitted over PUCCH and/or each HARQ-ACK response transmitted over PUSCH.

Spatial bundling may be supported when the maximum number of TBs (or codewords) that can be received at a time (or scheduled via 1 DCI) in a corresponding serving cell is 2 (or more than 2) (e.g., when the upper layer parameter maxNrofCodeWordsScheduledByDCI corresponds to 2-TB). Meanwhile, more than four layers may be used for 2-TB transmission, and at most four layers may be used for 1-TB transmission. Consequently, when spatial bundling is configured for a corresponding cell group, spatial bundling may be performed for serving cells in which more than four layers among serving cells in the corresponding cell group are schedulable. On the corresponding serving cell, a UE that wishes to transmit a HARQ-ACK response via spatial bundling may generate the HARQ-ACK response by performing a (bit-wise) logical AND operation on the A/N bits for multiple TBs.

For example, assuming that a terminal receives a DCI scheduling 2 TB and receives 2 TB over a PDSCH based on the DCI, the terminal performing spatial bundling can generate a single A/N bit by performing a logical AND operation on the first A/N bit for the first TB and the second A/N bit for the second TB. As a result, if both the first TB and the second TB are ACK, the terminal reports the ACK bit value to the base station, and if either TB is NACK, the terminal reports the NACK bit value to the base station.

For example, if only 1-TB is actually scheduled on a serving cell configured to receive 2-TB, the terminal can generate a single A/N bit by performing a logical AND operation on the A/N bit for the 1-TB and the bit value 1. As a result, the terminal reports the A/N bit for the 1-TB to the base station as is.

There are multiple parallel DL HARQ processes in a base station/terminal for DL transmission. The multiple parallel HARQ processes allow DL transmission to be performed continuously while waiting for HARQ feedback on successful or unsuccessful reception of previous DL transmission. Each HARQ process is associated with a HARQ buffer of a MAC (Medium Access Control) layer. Each DL HARQ process manages state variables such as the number of transmissions of MAC PDUs (Physical Data Blocks) in the buffer, HARQ feedback for MAC PDUs in the buffer, and current redundancy version. Each HARQ process is distinguished by a HARQ process ID.

Figure 6 illustrates a PUSCH transmission process. Referring to Figure 6, a terminal can detect a PDCCH in slot #n. Here, the PDCCH includes uplink scheduling information (e.g., DCI format 0_0, 0_1). DCI format 0_0, 0_1 can include the following information.

- Frequency domain resource assignment: Indicates the RB set allocated to PUSCH.

- Time domain resource assignment: Slot offset K2, indicating the starting position (e.g. symbol index) and length (e.g. number of OFDM symbols) of PUSCH within the slot. The starting symbol and length can be indicated through SLIV (Start and Length Indicator Value) or can be indicated separately.

Thereafter, the terminal can transmit PUSCH in slot #(n+K2) according to the scheduling information of slot #n. Here, the PUSCH includes UL-SCH TB.

CSI related actions

Figure 7 shows an example of a CSI-related procedure.

The terminal receives configuration information related to CSI from the base station via RRC signaling (710). The configuration information related to the CSI may include at least one of CSI-IM (interference management) resource related information, CSI measurement configuration related information, CSI resource configuration related information, CSI-RS resource related information, or CSI report configuration related information.

- CSI-IM resources can be set for interference measurement (IM) of a terminal. In the time domain, a set of CSI-IM resources can be set periodically, semi-persistently, or aperiodicly. The CSI-IM resources can be set as Zero Power (ZP)-CSI-RS for the terminal. The ZP-CSI-RS can be set to be distinct from the Non-Zero Power (NZP)-CSI-RS.

- The UE can assume that the CSI-RS resource(s) for channel measurement configured for one CSI reporting and the CSI-IM / NZP CSI-RS resource(s) for interference measurement (when NZP CSI-RS resource(s) are used for interference measurement) are in QCL relationship with respect to 'QCL-TypeD' per resource.

- CSI resource configuration may include at least one of a CSI-IM resource for interference measurement, an NZP CSI-RS resource for interference measurement, and an NZP CSI-RS resource for channel measurement. The CMR (channel measurement resource) may be an NZP CSI-RS for CSI acquisition, and the IMR (Interference measurement resource) may be an NZP CSI-RS for CSI-IM and IM.

- CSI-RS can be configured for one or more terminals. Different CSI-RS configurations may be provided for each terminal, or the same CSI-RS configuration may be provided for multiple terminals. CSI-RS can support up to 32 antenna ports. CSI-RS corresponding to N (N is 1 or more) antenna ports can be mapped to N RE positions within a time-frequency unit corresponding to one slot and one RB. When N is 2 or more, N-port CSI-RS can be multiplexed in CDM, FDM and/or TDM manner. CSI-RS can be mapped to remaining REs except REs to which CORESET, DMRS and SSB are mapped. In the frequency domain, CSI-RS can be configured for the entire bandwidth, a portion of the bandwidth (BWP) or a portion of the bandwidth. A CSI-RS may be transmitted in each RB within a bandwidth for which a CSI-RS is configured (density = 1), or in every second RB (e.g., an even-numbered or odd-numbered RB) (density = 1/2). When the CSI-RS is used as a Tracking Reference Signal (TRS), a single-port CSI-RS may be mapped on three subcarriers in each resource block (density = 3). One or more CSI-RS resource sets may be configured for a UE in the time domain. Each CSI-RS resource set may include one or more CSI-RS configurations. Each CSI-RS resource set may be configured periodically, semipersistently, or aperiodicly.

- The CSI report configuration may include configurations for a feedback type, measurement resources, report type, etc. The NZP-CSI-RS resource set may be used for the CSI report configuration of the corresponding terminal. The NZP-CSI-RS resource set may be associated with a CSI-RS or an SSB. In addition, multiple periodic NZP-CSI-RS resource sets may be configured as TRS resource sets. (i) The feedback type may include a Channel Quality Indicator (CQI), a Precoding Matrix Indicator (PMI), a CSI-RS Resource Indicator (CRI), an SSB Resource block Indicator (SSBRI), a Layer Indicator (LI), a Rank Indicator (RI), a Layer 1-Reference Signal Received Strength (RSRP), etc. (ii) The measurement resources may include configurations for downlink signals and/or downlink resources on which the terminal performs measurements to determine feedback information. The measurement resources may be configured as ZP and/or NZP CSI-RS resource sets associated with the CSI reporting configuration. The NZP CSI-RS resource set may include a CSI-RS set or an SSB set. For example, L1-RSRP may be measured for the CSI-RS set or may be measured for the SSB set. (iii) The reporting type may include configurations for a time point at which the terminal performs reporting and an uplink channel, etc. The reporting time point may be configured as periodic, semi-persistent or aperiodic. Periodic CSI reporting may be transmitted on PUCCH. Semi-persistent CSI reporting may be transmitted on PUCCH or PUSCH based on MAC CE indicating activation/deactivation. Aperiodic CSI reporting may be indicated by DCI signaling. For example, the CSI request field of an uplink grant may indicate one of several report trigger sizes. Aperiodic CSI reports may be transmitted on the PUSCH.

The terminal measures CSI based on configuration information related to CSI. CSI measurement may include a procedure of receiving CSI-RS (720) and computing the received CSI-RS to acquire CSI (730).

The UE can transmit a CSI report to the base station (740). For the CSI report, time and frequency resources that the UE can use are controlled by the base station. The CSI (channel state information) can include at least one of a channel quality indicator (CQI), a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), an SS/PBCH block resource indicator (SSBRI), a layer indicator (LI), a rank indicator (RI), L1-RSRP, and/or L-SINR.

Time domain behavior of CSI reporting supports periodic, semi-persistent, and aperiodic. i) Periodic CSI reporting is performed on short PUCCH and long PUCCH. The periodicity and slot offset of periodic CSI reporting can be set to RRC, and refer to the CSI-ReportConfig IE. ii) SP (semi-periodic) CSI reporting is performed on short PUCCH, long PUCCH, or PUSCH. In case of SP CSI on short/long PUCCH, the periodicity and slot offset are set to RRC, and CSI reporting is activated/deactivated by separate MAC CE/DCI. In case of SP CSI on PUSCH, the periodicity of SP CSI reporting is set to RRC, but the slot offset is not set to RRC, and SP CSI reporting is activated/deactivated by DCI (format 0_1). For SP CSI reporting on PUSCH, a separate RNTI (SP-CSI C-RNTI) is used. The timing of the first CSI report follows the PUSCH time domain allocation value indicated in DCI, and the timing of the subsequent CSI reports follows the cycle set by RRC. DCI format 0_1 includes a CSI request field and can activate/deactivate a specific configured SP-CSI trigger state. SP CSI reporting has the same or similar activation/deactivation mechanism as the data transmission mechanism on SPS PUSCH. iii) Aperiodic CSI reporting is performed on PUSCH and is triggered by DCI. In this case, information related to the trigger of aperiodic CSI reporting can be transmitted/indicated/configured via MAC-CE. In case of AP CSI with AP CSI-RS, the AP CSI-RS timing is configured by RRC, and the timing for AP CSI reporting is dynamically controlled by DCI.

QCL (quasi-co location)

Two antenna ports are quasi co-located if the channel properties of one antenna port can be inferred from the channel properties of the other antenna port. The channel properties may include one or more of Delay spread, Doppler spread, Frequency/Doppler shift, Average received power, Received Timing/average delay, and Spatial RX parameters.

A terminal may set a list of multiple TCI-State configurations via the upper layer parameter PDSCH-Config. Each TCI-State is associated with one or two DL reference signals and a QCL configuration parameter between the DM-RS port of the PDSCH. The QCL may include qcl-Type1 for the first DL RS and qcl-Type2 for the second DL RS. The QCL type may correspond to one of the following:

- '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}

M-TRP(multiple-transmission/reception point) related operations

Fig. 8 illustrates a multi-TRP transmission. Referring to Fig. 8(a), groups of layers transmitting the same CW (codeword) (or TB) correspond to different TRPs. Referring to Fig. 8(b), different CWs are transmitted through layer groups of different TRPs. At this time, it can be assumed that TBs corresponding to CW #1 and CW #2 in the figure are the same. CW #1 and CW #2 mean that the same TB is converted into different CWs through channel coding, etc. by different TRPs, respectively. Therefore, it can be viewed as an example of repeated transmission of the same TB. In the case of Fig. 8(b), compared to Fig. 8(a), it may have a disadvantage in that the code rate corresponding to the TB is high. However, it has an advantage in that the code rate can be adjusted or the modulation order of each CW can be adjusted by indicating different RV (redundancy version) values for encoded bits generated from the same TB depending on the channel environment.

According to the method exemplified in Fig. 8(a) and Fig. 8(b), the same TB is repeatedly transmitted through different layer groups, and since each layer group is transmitted by different TRPs/panels, the data reception probability of the terminal can be increased. This is referred to as an SDM (Spatial Division Multiplexing)-based M-TRP URLLC transmission method. Layers belonging to different layer groups are transmitted through DMRS ports belonging to different DMRS CDM groups, respectively.

In addition, although the above-described multiple TRP related content has been explained based on the SDM (spatial division multiplexing) method using different layers, it can be extended and applied to the FDM (frequency division multiplexing) method based on different frequency domain resources (e.g., RB/PRB (set) etc.) and/or the TDM (time division multiplexing) method based on different time domain resources (e.g., slots, symbols, sub-symbols etc.).

Design of 64 and 128 CSI-RS ports

In order to increase the system throughput of DL/UL in Rel-19 NR MIMO or later standards and to provide more flexible MIMO operation, the number of base station Tx/Rx antenna ports is being considered to be increased compared to the existing legacy (e.g., 32port Tx). To support this, a new 64/128port CSI-RS design is required, and this specification proposes methods for this.

Table 6 shows the CSI-RS mapping method defined in the existing NR standard (TS 38.211, Rel. 17).

As shown in Table 6, CSI-RS of NR is supported based on FDM/TDM/CDM. Fig. 9 illustrates CSI-RS mapped based on FDM/TDM/CDM in this way.

Based on the above CSI-RS design, it can be expanded to 64 port / 128 port CSI-RS, and for 64 port/128 port CSI-RS configuration, the following combinations can be considered as in Table 7. Table 7 shows the number of CDM groups required for expansion to 64/128 ports.

64 port CSI-RS 128 port CSI-RS FD CDM-2 32 64 FD2-TD2 CDM-4 16 32 FD2-TD4 CDM-8 8 16

Based on the above CDM-2, in order to support 64 port CSI-RS and/or 128 port CSI-RS, the number of configurations that must be set is 32 or 64, which results in very large signaling overhead. Table 8 below shows examples of FD CDM-2, FD2-TD2 CDM-4, and FD2-TD4 CDM-8 configurations of 64 port CSI-RS.

In addition, since the transmission power per port may decrease as the number of ports increases in the existing CDM, it is necessary to introduce a larger size CDM for this purpose. To this end, the following is proposed.

Proposal 1

To support 64 port / 128 port CSI-RS, CDM-16 configuration can be applied, and FD4-TD4 CDM-16 and/or FD2-TD8 CDM-16 configuration can be supported.

Fig. 10 illustrates the CDM-16 pattern of Proposal 1. Based on this CDM-16, 64 ports require 4 CDM-16 groups, 128 ports require 8 CDM-16 groups, and the CDM groups are aggregated to configure 64 port, 128 port CSI-RS. And Tables 9 and 10 below show the CDM sequences of FD4-TD4 CDM-16 and FD2-TD8 CDM-16, respectively.

Proposal 2

In a 64 port/128 port CSI-RS design, we propose the following time domain / frequency domain density reduction.

(1) Option 1. Time domain density reduction

Figures 11 and 12 illustrate an example for option 1 of proposal 2. Figure 12 shows the case where k is fixed to 1.

Among multiple CDM-X groups (e.g., X = 2 or 4 or 8 or 16) constituting 64 or 128 port CSI-RS, a first set of Y CDM groups is transmitted in the n-th slot, and a second set of Z CDM groups is transmitted in the n+k-th slot. Here, X*(Y+Z) = P (64 or 128), and when X*Y CSI-RSs transmitted periodically/semi-persistent/aperiodicly are transmitted n times, X*Z CSI-RSs are transmitted in the k-th slot (k is RRC configurable, based on the UE capability of the terminal, or can be fixed to a specific value, e.g., k=1). As a special case of the above example, when the number of ports of CSI-RSs transmitted in each slot is the same, Y=Z=64/2 or 128/2 port CSI-RS.

(2) Option 2. Frequency domain density reduction

FIGS. 13 to 15 illustrate an example for option 2 of proposal 2. Specifically, (i) FIG. 13 illustrates an example for option 2, 64 port CSI-RS. (ii) FIG. 14 illustrates an example for option 2, 64 port CSI-RS with 0.5 CSI-RS density (port/RE/RB). In FIG. 14, the density is 64-port / 64-RE / 2-RB = 0.5 port/RE/RB. (iii) FIG. 15 illustrates an example for option 2, 128 port CSI-RS with 0.25 CSI-RS density (port/RE/RB). In FIG. 15, the density is 128-port / (16*8)-RE / 4-RB = 0.25 port/RE/RB.

Among multiple CDM-X groups (e.g., X = 2 or 4 or 8 or 16) configuring 64 or 128 port CSI-RS, the first set of Y CDM groups is transmitted to even PRB, and the second set of Z CDM groups is transmitted to odd PRB. Here, X*(Y+Z) = P (64 or 128). As a special case of the above example, when the number of ports of CSI-RS transmitted in each slot is the same, Y=Z=64/2 or 128/2 port CSI-RS can be set.

In the case of the above proposal 2, the number of REs per PRB occupied by 64 port CSI-RS and 128 port CSI-RS is too large, so this is a measure to effectively reduce RS overhead.

In FIGS. 11 to 13, it is assumed that the base station instructs/configures different CDM configurations for each PRB of different frequency/time resources. However, in order to reduce signaling/configuration overhead, it may be considered that the CDM group configuration pattern of one PRB is repeated, as in FIG. 14. The configuration in FIG. 14 means that when a CSI-RS configuration for an even (odd) PRB is given (configuration/instruction for 4 CDM-8s in FIG. 14 and the total number of CSI-RS ports (64port CSI-RS) and/or CSI-RS density), the CSI-RS pattern is repeatedly set for the odd (even) PRB. This was explained based on option 2, but it can also be extended to option 1.

In Fig. 11, CSI-RSs corresponding to the 1st CDM-8 to the 4th CDM-8 (n-th slot CSI-RS) can correspond to one CSI-RS resource #1, and CSI-RSs corresponding to the 5th CDM-8 to the 8th CDM-8 ((n+k)th slot CSI-RS) can correspond to CSI-RS resource #2. Extending the above example, CSI-RS resources #1, #2, ...#N aggregated for configuring 64 port or 128 port CSI-RS can be set/transmitted in different time slots. Alternatively, the plurality of resources can be grouped and transmitted in different time slots for each group. As also shown in Proposal 3 described below, when multiple CSI-RSs are aggregated to configure 64 ports or 128 ports and transmitted across multiple slots, one resource is set to be transmitted within the same slot or T slots/symbols in consideration of channel coherence time. For example, according to the embodiment where k is fixed to 1 as described above, T may correspond to two consecutive slots. The reason why such a constraint is necessary is that when CSI-RS resources are transmitted in each of slots that are far apart from each other in the time domain, the coherency property may not be maintained between these CSI-RS resources, and acquiring CSI based on the aggregation of CSI-RS resources may be inaccurate/inappropriate. On the other hand, if all CSI-RS resources are mapped to the same slot, the coherency property can be maintained, but as the number of ports increases, such as 64 or 128 ports, the overhead of the CSI-RS in the slot becomes excessively large, and other signals/channels may not be transmitted or may collide with them. To compromise the gain between overhead reduction and coherence, the aggregated CSI-RS resources within the coherence time corresponding to T slots can be mapped with a lower time domain density.

For example, in the case of the T value, it can be a value configured by the base station, set based on the coherence time, or determined by the capability report of the terminal. In the case of determining by the coherence time, the T value can be determined as in mathematical expression 1, for example.

In Equation 1, fm is the maximum Doppler spread, v is the velocity, and λ is the wavelength. Alternatively, the terminal may measure the channel based on TRS, and the base station may set the T value based on the TDCP (time domain channel property) report, which is a report on its correlation measurement value.

In Fig. 13/14, a CSI-RS density of, for example, 0.5 port/RE/RB, is considered, where all 64 or 128 ports are repeatedly transmitted every 2 PRBs. Here, the PRBs to which the 1st to 4th CDM-8 belong have a PRB offset value of 0, and the PRBs to which the 5th to 8th CDM-8 belong are examples where the offset value is 1. In other words, the CSI-RS resources corresponding to the 1st to 4th CDM-8 can be transmitted only in even PRBs, and the CSI-RS resources corresponding to the 5th to 8th CDM-8 can be transmitted only in odd PRBs. In the above case, since both consecutive PRBs are used, no additional offset signaling is necessary. However, for further RS overhead reduction, a CSI-RS density of a smaller value (e.g., 0.25) can be considered for configuring/instructing the 64 ports or 128 ports. In this case, it means that 64 port or 128 port CSI-RS is repeated every 4 PRBs. In the case of the 0.25 density, two steps of PRB offset values may be required to indicate this. For example, the first PRB offset (e.g., PRBs to which 1 to 4-th CDM-8 belong in the example of Fig. 14) may be indicated by one of three values: 0, 1, 2, and the second offset (e.g., PRBs to which 5 to 8-th CDM-8 belong in the example of Fig. 14) may be indicated by one of the values: 1, 2, 3. Alternatively, a method of jointly indicating two offsets as follows, such as (0,1), (0,2), (0,3), (1,2) (1,3), (2,3) can also be considered.

Another way to set the CSI-RS density 0.25 is to set 32 port CSI-RS to PRB offset 0, 32 port CSI-RS to PRB offset 1, 32 port CSI-RS to PRB offset 2, and 32 port CSI-RS to PRB offset 3, for example, in the case of 128 ports. In this case, signaling for the PRB offset is not necessary, as illustrated in FIG. 15. Generalizing FIGS. 14 and 15, in the case of P port CSI-RS, as many CSI-RS ports as P * CSI-RS density are mapped to each PRB with a PRB offset of 1 to configure the P port. This has the advantage of being able to reuse the existing CSI-RS configuration, and thus, there is no need for RS density and PRB offset signaling. CSI-RS ports set to different PRB offsets in FIGS. 14/15 can be distinguished as different CSI-RS resources.

As a combination of the above options 1 and 2, a method of maximizing the configuration flexibility by setting different time/frequency resources can also be considered. For example, the CSI-RSs of the nth slot in Fig. 11 (e.g., PRBs to which the 1st to 4th CDM-8 belongs) can be transmitted for every even PRB, and the CSI-RSs of the n+kth slot (e.g., PRBs to which the 5th to 8th CDM-8 belongs) can be transmitted for every odd PRB.

Meanwhile, instead of designing a new 64 port/128 port CSI-RS, one can consider designing a 64 port/128 port CSI-RS by aggregating multiple legacy CSI-RS configurations. For example, one can configure 64 ports by aggregating two legacy 32 port CSI-RS resources, or one can configure 128 ports by aggregating four resources. In this case, one can also consider CSI-RS port indexing to match the aggregated CSI-RS with the codebook port.

Proposal 3

When configuring a 64 port / 128 port CSI-RS by aggregating legacy CSI-RSs, the port indexing in the following mathematical expression 2 is followed.

In Equation 2, N represents # of CSI-RS ports per resource, K represents # of aggregated CSI-RS resources, L∈{1,2,4,8} represents the CDM group size, and s represents the sequence index within the CDM group.

In the case of the above proposal 3, it is a formula for port indexing while multiple CSI-RS resources are sequentially aggregated. For example, when two 32 port CSI-RSs are aggregated, the first resource is indexed from 3000 to 3031, and the second resource is indexed from 3032 to 3063. In this case, which CSI-RS resource is indexed first (index k) can be indexed in the order in which the base station configures the CSI-RS resources in the CSI-RS resource Config, or can be indexed in the lowest/highest order based on the CSI-RS resource id. Or, in the overhead reduction of the above proposal 2, indexing can be performed in the order of the CSI-RS resource configured in the lowest/highest PRB or slot based on the reference PRB (k=0) or the reference slot n. For example, in FIG. 15, if CSI-RSs configured with 1st-4th CDM-8 are configured as the second CSI-RS resource, CSI-RSs configured with 5th-8th CDM-8 are configured as the first CSI-RS resource, CSI-RSs configured with 9th-12th CDM-8 are configured as the third CSI-RS resource, and CSI-RSs configured with 13th-16th CDM-8 are configured as the fourth CSI-RS resource, the indexing order is 2nd→1st→3rd→4th CSI-RS resource. In addition, CSI-RS port indexing within each resource is indexed by the formula of s+jL above.

As another example, when multiple CSI-RS resources are configured together in one PRB, CSI-RS port indexing is performed in the order of resources to which the lowest/highest symbol index or lowest/highest subcarrier index belongs among the REs occupied by the CSI-RSs in each resource. In Fig. 16, CSI-RS resource #2 is indexed first, and then CSI-RS resource #1 is indexed.

As another example, by re-ordering the CDM-groups composed of the aggregated CSI-RSs, port indexing can be performed in the order of the CDM-group index. The order of indexing the CDM groups is to reorder the CDM groups in the order of frequency → time. For example, in the case of Fig. 16, the 1st CDM-8 to the 4th CDM-8 of CSI-RS resource #2 become the 1st CDM-8 to the 4th CDM-8, and the 1st CDM-8 to the 4th CDM-8 of CSI-RS resource #1 become the 5th CDM-8 to the 8th CDM-8. Following an example of Fig. 17, the order of CDM groups is 1st - 4th CDM-4 of CSI-RS resource #1 → 1st - 4th CDM-4 of CSI-RS resource #2 → 5th - 8th CDM-4 of CSI-RS resource #1 → 5th - 8th CDM-4 of CSI-RS resource #2, and the CDM groups are reordered in this order. In this case, the formula has an advantage in that it can follow the legacy formula (p=3000+s+jL) as it is. In addition, in case of Proposal 3, if multiple resources have different numbers of ports, for example, if the 64 port configuration is CSI-RS resource #1 (32 ports) + CSI-RS resource #2 (16 ports) + CSI-RS resource #3 (16 ports), the above formula can be borrowed as it is. However, in this case, the order of resource aggregation can be port indexing in the order of larger/smaller number of ports.

Meanwhile, reusing legacy CSI-RSs means that specific CSI-RS resources are set for legacy UEs, and since the base station is equipped with a cross-pol antenna, CSI-RSs corresponding to two polls are transmitted within one resource, and the codebook is configured accordingly. For example, in the example of a 32 port configuration as in FIG. 18, the first 16 ports correspond to the "/" slant, and the remaining 16 ports correspond to the "＼" slant. Accordingly, the codebook is also designed in a block diagonal form to apply a DFT vector to each port corresponding to each slant.

However, if we follow Proposal 3, port indexing is performed sequentially for each CSI-RS resource, so although it is actually a CSI-RS mapped to cross pol, due to the indexing, it can only be mapped to the same slant. For this, we propose the following port indexing.

Proposal 3-1

When configuring a 64 port / 128 port CSI-RS by aggregating legacy CSI-RSs, the port indexing in mathematical expression 3 is followed.

The ordering (index k) of the CSI-RS resources aggregated in Equation 3 can be directly borrowed from the method of Proposal 3.

According to Equation 3, half of the ports in the aggregated CSI-RS resource are mapped to the "/" slant, and the remaining ports are mapped to the "＼" slant.

Fig. 19 is an example of configuring a 64 port CSI-RS by aggregating two legacy 32 port CSI-RSs and port indexing. In Fig. 19, (a) is a 64 port CSI-RS configured by aggregating two legacy 32 port CSI-RSs, (b) is port indexing according to Proposal 3, and (c) is port indexing according to Proposal 3-1. In Fig. 19, assuming that legacy UEs are also supported at the same time, it is illustrated that legacy CSI-RSs each support a legacy 32 port UE. If only the legacy CSI-RS configuration is reused and the actual port mapping is that CSI-RS resource #1 is mapped to "/" slant and CSI-RS resource #2 is mapped to "＼" slant, the result of Proposal 3 is as shown in Fig. 19 (c). In addition, the port indexing method can be selectively used depending on the CSI reporting quantity or codebook structure. For example, in the case of Proposal 3, it is easy to apply to a case where multiple CRIs (CSI-RS resource indicators) are selected from multiple CSI-RS resources and CSI (e.g., RI/CQI/PMI) is reported for each resource or to a multi-panel codebook, and in the case of Proposal 3-1, it is easy to apply to a single-panel codebook consisting of 64 or 128 port CSI-RS.

In addition, if we generalize Proposal 3-1 to the case where multiple resources have different numbers of ports, it is as shown in Equation 4.

∑ _k=0 ^K-1 N _k = P(64/128 ports). Also, in Equation 4, we generalize by assuming different CDM-sizes for each resource, but if the CDM-sizes are different, it may cause power imbalance between ports, so the CDM-size can be restricted to be the same across CSI-RS resources.

Additionally, when designing a multi-panel CSI codebook, ports belonging to the same panel can be restricted to be included in the same CDM group and/or the same CSI-RS resource, and ports belonging to different panels can be restricted to be included in different CDM groups and/or different CSI-RS resources. Similarly, when designing a single panel rank 3-4, two port sub-groups are considered for one panel, and by the same principle as above, in the case of the same port sub-group, they can be restricted to be included in the same CDM group and/or CSI-RS resource.

In the above proposal, when multiple or single CSI-RS resources are transmitted in TDM across multi-slot or FDM across multi-PRM, the problem arises of how to resolve the case of collision with other signals/channels. Here, resource collision means the case where part or all of the time/frequency resources of one resource overlap. The following method is proposed for the collision handling.

# In case some of the resources that make up 64/128 CSI-RS collide with higher priority signals/channels (e.g., SSB, CORESET, DM-RS) than CSI-RS:

(1) Method 1: Drop all 64/128 port CSI-RS.

Even when multiple CSI-RS resources are aggregated to form a 64/128 port CSI-RS, all of the multiple resources are dropped.

(2) Method 2: Among the multiple resources that constitute the 64/128 port CSI-RS, all ports in the overlapping resources are dropped.

For example, when two resources are aggregated to configure 64 ports (e.g., 32+32), if the ports corresponding to the second 32 port CSI-RS resource overlap, 32 ports are dropped and only the remaining 32 port CSI-RS is transmitted. In this case, even if the terminal is configured with 64 ports, the report is performed for 32 port CSI-RS. The terminal can find out whether specific ports are dropped based on a predefined priority rule, or the base station can notify the terminal whether or not to drop through a separate instruction.

(3) Method 3: Among the multiple resources that constitute the 64/128 port CSI-RS, overlapping resources are transmitted by performing time domain and/or frequency domain shift.

Among the CSI-RS resources configuring single or multiple 64/128 port CSI-RSs, collided resources are promised to be transmitted by shifting in the time axis or frequency axis (based on a pre-defined rule). The base station can set whether the C symbol/slot and/or D RE/RB are shifted in the time/frequency axis. Otherwise, it can be determined to be located within the above-described coherence time.

(4) Method 4: The terminal does not expect that the configured/transmitted CSI-RS resources collide with a channel/signal of higher priority than the CSI-RS. In addition, when the terminal aggregates multiple CSI-RS resources to configure a 64-port or 128-port CSI-RS, it does not expect collisions among the resources. For example, multiple CSI-RS resources are not configured/indicated to overlap each other within the time/frequency resource.

Figure 20 is an example of the operation procedures of the base station and terminal for Proposals 1/2/3/3-1. In Figure 20, some terminal/base station operations may be omitted.

Referring to FIG. 20, a terminal can transmit a UE capability report including the number of supportable CSI-RS ports and the total number of simultaneously supportable CSI-RS ports to a base station (2005).

The terminal can receive configuration information related to CSI-RS and configuration information related to CSI reporting from the base station (2010).

The terminal can receive CSI-RS from the base station (2015) and measure/predict/calculate CSI based on this (2020).

The terminal can report measured/predicted/calculated CSI to the base station (2025).

The terminal can receive scheduling information (e.g., DCI) for a downlink channel (e.g., PDCCH, PDSCH) from the base station (2030).

The terminal can receive a downlink channel/signal transmitted by the base station (2035).

FIG. 21 illustrates a flow of a method performed by a terminal according to one embodiment.

Referring to FIG. 21, a terminal can receive CSI-RS (channel state information - reference signal) settings through upper layer signaling (2105).

The terminal can receive CSI-RS based on the above CSI-RS settings (2110).

The terminal can obtain CSI based on the above CSI-RS (2115).

The above CSI-RS is provided through P antenna ports, where P can be an integer greater than 32 and not exceeding 128.

The above CSI-RS configuration may include configurations for multiple CSI-RS resources related to the P antenna ports.

The configuration for the above multiple CSI-RS resources may include information about the slot offset value of each CSI-RS resource.

The above plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

The above T slots can be two consecutive slots.

The above P can be 64 or 128.

Each CSI-RS resource can be mapped to one of the two slots based on the slot offset value.

The CSI can be acquired based on the aggregation of CSI-RS resources mapped to the first slot among the above two slots and CSI-RS resources mapped to the second slot.

The above slot offset value can be 0 or 1.

The density of the CSI-RS, which is determined based on the number P of antenna ports for the CSI-RS, the number of REs (resource elements) and the number of RBs (resource blocks), may be 0.5.

Each CSI-RS resource can be mapped to either an even physical resource block (PRB) or an odd PRB in the frequency domain.

Among the plurality of CSI-RS resources, a first CSI-RS resource may be mapped to an even PRB of a first slot among the T slots, and a second CSI-RS resource may be mapped to an odd PRB of a second slot among the T slots.

The above terminal may not expect that the above multiple CSI-RS resources will collide with other signals having higher priority than the CSI-RS.

The above CSI-RS may be aperiodic CSI-RS.

FIG. 22 illustrates a flow of a method performed by a base station according to one embodiment.

Referring to FIG. 22, the base station can transmit CSI-RS (channel state information - reference signal) settings to the terminal through upper layer signaling (2205).

The base station can transmit CSI-RS to the terminal based on the CSI-RS settings (2210).

The base station can receive a CSI report from the terminal (2215).

The above CSI-RS is provided through P antenna ports, where P can be an integer greater than 32 and not exceeding 128.

The above CSI-RS configuration may include configurations for multiple CSI-RS resources related to the P antenna ports.

The configuration for the above multiple CSI-RS resources may include information about the slot offset value of each CSI-RS resource.

The above plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

The above T slots can be two consecutive slots.

The above P can be 64 or 128.

Each CSI-RS resource can be mapped to one of the two slots based on the slot offset value.

The above CSI report may include CSI obtained based on an aggregation of CSI-RS resources mapped to a first slot among the two slots and CSI-RS resources mapped to a second slot.

The above slot offset value can be 0 or 1.

The density of the CSI-RS, which is determined based on the number P of antenna ports for the CSI-RS, the number of REs (resource elements) and the number of RBs (resource blocks), may be 0.5.

Each CSI-RS resource can be mapped to either an even physical resource block (PRB) or an odd PRB in the frequency domain.

Among the plurality of CSI-RS resources, a first CSI-RS resource may be mapped to an even PRB of a first slot among the T slots, and a second CSI-RS resource may be mapped to an odd PRB of a second slot among the T slots.

The above base station can schedule the plurality of CSI-RS resources so that they do not collide with other signals having a higher priority than the CSI-RS.

The above CSI-RS may be aperiodic CSI-RS.

Fig. 23 illustrates a communication system (1) applicable to various embodiments.

Referring to FIG. 23, the communication system (1) includes a wireless device, a base station, and a network. Here, the wireless device means a device that performs communication using a wireless access technology (e.g., 5G NR (New RAT), LTE (Long Term Evolution)) and may be referred to as a communication/wireless/5G device. Although not limited thereto, the wireless device may include a robot (100a), a vehicle (100b-1, 100b-2), an XR (eXtended Reality) device (100c), a hand-held device (100d), a home appliance (100e), an IoT (Internet of Thing) device (100f), and an AI device/server (400). For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous vehicle, a vehicle capable of performing vehicle-to-vehicle communication, etc. Here, the vehicle may include an Unmanned Aerial Vehicle (UAV) (e.g., a drone). XR devices include AR (Augmented Reality)/VR (Virtual Reality)/MR (Mixed Reality) devices and can be implemented in the form of HMD (Head-Mounted Device), HUD (Head-Up Display) installed in a vehicle, television, smartphone, computer, wearable device, home appliance, digital signage, vehicle, robot, etc. Portable devices can include smartphone, smart pad, wearable device (e.g., smart watch, smart glass), computer (e.g., laptop, etc.). Home appliances can include TV, refrigerator, washing machine, etc. IoT devices can include sensors, smart meters, etc. For example, base stations and networks can also be implemented as wireless devices, and a specific wireless device (200a) can act as a base station/network node to other wireless devices.

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

Wireless communication/connection (150a, 150b, 150c) can be established between wireless devices (100a to 100f)/base stations (200), and base stations (200)/base stations (200). Here, the wireless communication/connection can be achieved through various wireless access technologies (e.g., 5G NR) such as uplink/downlink communication (150a), sidelink communication (150b) (or, D2D communication), and communication between base stations (150c) (e.g., relay, IAB (Integrated Access Backhaul)). Through the wireless communication/connection (150a, 150b, 150c), a wireless device and a base station/wireless device, and a base station and a base station can transmit/receive wireless signals to/from each other. For example, the wireless communication/connection (150a, 150b, 150c) can transmit/receive signals through various physical channels. To this end, at least some of various configuration information setting processes for transmitting/receiving wireless signals, various signal processing processes (e.g., channel encoding/decoding, modulation/demodulation, resource mapping/demapping, etc.), and resource allocation processes can be performed based on various proposals of the present invention.

Figure 24 illustrates a wireless device that can be applied to various embodiments.

Referring to FIG. 24, the first wireless device (100) and the second wireless device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, NR). Here, {the first wireless device (100), the second wireless device (200)} can correspond to {the wireless device (100x), the base station (200)} and/or {the wireless device (100x), the wireless device (100x)} of FIG. 23.

A first wireless device (100) includes one or more processors (102) and one or more memories (104), and may additionally include one or more transceivers (106) and/or one or more antennas (108). The processor (102) controls the memory (104) and/or the transceiver (106), and may be configured to implement the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this document. For example, the processor (102) may process information in the memory (104) to generate first information/signal, and then transmit a wireless signal including the first information/signal via the transceiver (106). Additionally, the processor (102) may receive a wireless signal including second information/signal via the transceiver (106), and then store information obtained from signal processing of the second information/signal in the memory (104). The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software codes including instructions for performing the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. Here, the processor (102) and the memory (104) may be part of a communication modem/circuit/chip designed to implement wireless communication technology (e.g., LTE, NR). The transceiver (106) may be connected to the processor (102) and may transmit and/or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and/or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present invention, a wireless device may also mean a communication modem/circuit/chip.

The second wireless device (200) includes one or more processors (202), one or more memories (204), and may additionally include one or more transceivers (206) and/or one or more antennas (208). The processor (202) may be configured to control the memories (204) and/or the transceivers (206), and implement the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this document. For example, the processor (202) may process information in the memory (204) to generate third information/signals, and then transmit a wireless signal including the third information/signals via the transceivers (206). Additionally, the processor (202) may receive a wireless signal including fourth information/signals via the transceivers (206), and then store information obtained from signal processing of the fourth information/signals in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may perform some or all of the processes controlled by the processor (202), or may store software codes including commands for performing the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. Here, the processor (202) and the memory (204) may be part of a communication modem/circuit/chip designed to implement wireless communication technology (e.g., LTE, NR). The transceiver (206) may be connected to the processor (202) and may transmit and/or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and/or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present invention, a wireless device may also mean a communication modem/circuit/chip.

Hereinafter, hardware elements of the wireless device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and/or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, suggestions and/or methodologies disclosed herein and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed herein.

The one or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The one or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in the one or more processors (102, 202). The descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in this document may be implemented using firmware or software configured to perform one or more of the following: included in one or more processors (102, 202), or stored in one or more memories (104, 204) and driven by one or more of the processors (102, 202). The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in this document may be implemented using firmware or software in the form of codes, instructions and/or sets of instructions.

One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions and/or commands. The one or more memories (104, 204) may be comprised of ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer readable storage media and/or combinations thereof. The one or more memories (104, 204) may be located internally and/or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

One or more transceivers (106, 206) can transmit user data, control information, wireless signals/channels, etc., as described in the methods and/or flowcharts of this document, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals/channels, etc., as described in the descriptions, functions, procedures, suggestions, methods and/or flowcharts of this document, from one or more other devices. For example, one or more transceivers (106, 206) can be coupled to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals/channels, and the like, as described in the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed herein, via one or more antennas (108, 208). In this document, one or more antennas may be multiple physical antennas, or multiple logical antennas (e.g., antenna ports). One or more transceivers (106, 206) may convert received user data, control information, wireless signals/channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals/channels, etc. using one or more processors (102, 202). One or more transceivers (106, 206) may convert processed user data, control information, wireless signals/channels, etc. from baseband signals to RF band signals using one or more processors (102, 202). For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and/or filter.

Fig. 25 shows another example of a wireless device applied to the present invention. The wireless device can be implemented in various forms depending on the use-example/service (see Fig. 23).

Referring to FIG. 25, the wireless device (100, 200) corresponds to the wireless device (100, 200) of FIG. 24 and may be composed of various elements, components, units/units, and/or modules. For example, the wireless device (100, 200) may include a communication unit (110), a control unit (120), a memory unit (130), and an additional element (140). The communication unit may include a communication circuit (112) and a transceiver(s) (114). For example, the communication circuit (112) may include one or more processors (102, 202) and/or one or more memories (104, 204) of FIG. 24. For example, the transceiver(s) (114) may include one or more transceivers (106, 206) and/or one or more antennas (108, 208) of FIG. 24. The control unit (120) is electrically connected to the communication unit (110), the memory unit (130), and the additional elements (140) and controls overall operations of the wireless device. For example, the control unit (120) may control electrical/mechanical operations of the wireless device based on programs/codes/commands/information stored in the memory unit (130). In addition, the control unit (120) may transmit information stored in the memory unit (130) to an external device (e.g., another communication device) via a wireless/wired interface through the communication unit (110), or store information received from an external device (e.g., another communication device) via a wireless/wired interface in the memory unit (130).

The additional element (140) may be configured in various ways depending on the type of the wireless device. For example, the additional element (140) may include at least one of a power unit/battery, an input/output unit (I/O unit), a driving unit, and a computing unit. Although not limited thereto, the wireless device may be implemented in the form of a robot (FIG. 23, 100a), a vehicle (FIG. 23, 100b-1, 100b-2), an XR device (FIG. 23, 100c), a portable device (FIG. 23, 100d), a home appliance (FIG. 23, 100e), an IoT device (FIG. 23, 100f), a digital broadcasting terminal, a hologram device, a public safety device, an MTC device, a medical device, a fintech device (or a financial device), a security device, a climate/environmental device, an AI server/device (FIG. 23, 400), a base station (FIG. 23, 200), a network node, etc. Wireless devices may be mobile or stationary, depending on the use/service.

In FIG. 25, various elements, components, units/parts, and/or modules within the wireless device (100, 200) may be entirely interconnected via a wired interface, or at least some may be wirelessly connected via a communication unit (110). For example, within the wireless device (100, 200), the control unit (120) and the communication unit (110) may be wired, and the control unit (120) and the first unit (e.g., 130, 140) may be wirelessly connected via the communication unit (110). In addition, each element, component, unit/part, and/or module within the wireless device (100, 200) may further include one or more elements. For example, the control unit (120) may be composed of one or more processor sets. For example, the control unit (120) may be composed of a set of a communication control processor, an application processor, an electronic control unit (ECU), a graphic processing processor, a memory control processor, etc. As another example, the memory unit (130) may be composed of RAM (Random Access Memory), DRAM (Dynamic RAM), ROM (Read Only Memory), flash memory, volatile memory, non-volatile memory, and/or a combination thereof.

Fig. 26 illustrates a vehicle or autonomous vehicle applicable to various embodiments. The vehicle or autonomous vehicle may be implemented as a mobile robot, a car, a train, a manned/unmanned aerial vehicle (AV), a ship, etc.

Referring to FIG. 26, a vehicle or autonomous vehicle (100) may include an antenna unit (108), a communication unit (110), a control unit (120), a driving unit (140a), a power supply unit (140b), a sensor unit (140c), and an autonomous driving unit (140d). The antenna unit (108) may be configured as a part of the communication unit (110). Blocks 110/130/140a to 140d correspond to blocks 110/130/140 of FIG. 25, respectively.

The communication unit (110) can transmit and receive signals (e.g., data, control signals, etc.) with external devices such as other vehicles, base stations (e.g., base stations, road side units, etc.), servers, etc. The control unit (120) can control elements of the vehicle or autonomous vehicle (100) to perform various operations. The control unit (120) can include an ECU (Electronic Control Unit). The drive unit (140a) can drive the vehicle or autonomous vehicle (100) on the ground. The drive unit (140a) can include an engine, a motor, a power train, wheels, brakes, a steering device, etc. The power supply unit (140b) supplies power to the vehicle or autonomous vehicle (100) and can include a wired/wireless charging circuit, a battery, etc. The sensor unit (140c) can obtain vehicle status, surrounding environment information, user information, etc. The sensor unit (140c) may include an IMU (inertial measurement unit) sensor, a collision sensor, a wheel sensor, a speed sensor, an incline sensor, a weight detection sensor, a heading sensor, a position module, a vehicle forward/backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, a light sensor, a pedal position sensor, etc. The autonomous driving unit (140d) may implement a technology for maintaining a driving lane, a technology for automatically controlling speed such as adaptive cruise control, a technology for automatically driving along a set path, a technology for automatically setting a path and driving when a destination is set, etc.

For example, the communication unit (110) can receive map data, traffic information data, etc. from an external server. The autonomous driving unit (140d) can generate an autonomous driving route and a driving plan based on the acquired data. The control unit (120) can control the driving unit (140a) so that the vehicle or autonomous vehicle (100) moves along the autonomous driving route according to the driving plan (e.g., speed/direction control). During autonomous driving, the communication unit (110) can irregularly/periodically acquire the latest traffic information data from an external server and can acquire surrounding traffic information data from surrounding vehicles. In addition, the sensor unit (140c) can acquire vehicle status and surrounding environment information during autonomous driving. The autonomous driving unit (140d) can update the autonomous driving route and driving plan based on the newly acquired data/information. The communication unit (110) can transmit information on the vehicle location, autonomous driving route, driving plan, etc. to an external server. An external server can predict traffic information data in advance using AI technology, etc. based on information collected from vehicles or autonomous vehicles, and provide the predicted traffic information data to the vehicles or autonomous vehicles.

The embodiments described above are combinations of components and features of the present invention in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented in a form that is not combined with other components or features. In addition, it is also possible to form an embodiment of the present invention by combining some components and/or features. The order of 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 claims that do not have an explicit citation relationship in the scope of the patent may be combined to form an embodiment or included as a new claim by post-application amendment.

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

The present disclosure may be used in a terminal, a base station, or other equipment of a wireless mobile communication system.

Claims (15)

In a method performed by a terminal, Receive CSI-RS (channel state information - reference signal) configuration via upper layer signaling; Receive CSI-RS based on the above CSI-RS settings; and Including obtaining CSI based on the above CSI-RS, The above CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, The above CSI-RS configuration includes configurations for multiple CSI-RS resources related to the P antenna ports, The configuration for the above multiple CSI-RS resources includes information on the slot offset value of each CSI-RS resource, A method wherein the above plurality of CSI-RS resources are mapped within a time interval corresponding to T slots based on the slot offset value. In paragraph 1, The above T slots are two consecutive slots, The above P is 64 or 128. In the second paragraph, A method wherein each CSI-RS resource is mapped to one of the two slots based on the slot offset value. In the third paragraph, A method in which the CSI is obtained based on an aggregation of CSI-RS resources mapped to a first slot among the two slots and CSI-RS resources mapped to a second slot. In the third paragraph, The above slot offset value is 0 or 1. In paragraph 1, The density of the CSI-RS, which is determined based on the number P of the antenna ports for the CSI-RS, the number of REs (resource elements) and the number of RBs (resource blocks), is 0.5, A method in which each CSI-RS resource is mapped to either an even physical resource block (PRB) or an odd PRB in the frequency domain. In paragraph 6, A method wherein a first CSI-RS resource among the plurality of CSI-RS resources is mapped to an even PRB of a first slot among the T slots, and a second CSI-RS resource is mapped to an odd PRB of a second slot among the T slots. In paragraph 1, A method wherein the terminal does not expect the plurality of CSI-RS resources to collide with other signals having higher priority than the CSI-RS. In paragraph 1, A method wherein the above CSI-RS is aperiodic CSI-RS. A non-transitory computer-readable recording medium having recorded thereon instructions for performing the method described in claim 1. In the device, memory for storing commands; and A processor for performing operations by executing the above instructions, The operations of the above processor are: Receive CSI-RS (channel state information - reference signal) configuration via upper layer signaling; Receive CSI-RS based on the above CSI-RS settings; and Including obtaining CSI based on the above CSI-RS, The above CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, The above CSI-RS configuration includes configurations for multiple CSI-RS resources related to the P antenna ports, The configuration for the above multiple CSI-RS resources includes information on the slot offset value of each CSI-RS resource, A device wherein the above plurality of CSI-RS resources are mapped to time intervals corresponding to T slots based on the slot offset value. In Article 11, The above device further comprises a transceiver, The above device is a terminal operating in a wireless communication system. In Article 11, The above device is a processing device configured to control a terminal operating in a wireless communication system. In a method performed by a base station, Transmit CSI-RS (channel state information - reference signal) settings to the terminal via upper layer signaling; Transmitting CSI-RS to the terminal based on the above CSI-RS settings; and Including receiving a CSI report from the terminal, The above CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, The above CSI-RS configuration includes configurations for multiple CSI-RS resources related to the P antenna ports, The configuration for the above multiple CSI-RS resources includes information on the slot offset value of each CSI-RS resource, A method wherein the above plurality of CSI-RS resources are mapped within a time interval corresponding to T slots based on the slot offset value. At the base station, memory for storing commands; and A processor for performing operations by executing the above instructions, The operations of the above processor are: Transmit CSI-RS (channel state information - reference signal) settings to the terminal via upper layer signaling; Transmitting CSI-RS to the terminal based on the above CSI-RS settings; and Including receiving a CSI report from the terminal, The above CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, The above CSI-RS configuration includes configurations for multiple CSI-RS resources related to the P antenna ports, The configuration for the above multiple CSI-RS resources includes information on the slot offset value of each CSI-RS resource, A base station, wherein the above plurality of CSI-RS resources are mapped within a time interval corresponding to T slots based on the slot offset value.

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