Terminal, wireless communication method, base station and system

Abstract

A terminal according to one aspect of the present disclosure comprises: a reception unit that receives downlink control information (DCI) for scheduling an uplink shared channel; and a control unit that selects, on the basis of a specific field of the DCI, an antenna port indication table relating to a demodulation reference signal (DMRS) port indication for the uplink shared channel from among a plurality of tables for a certain rank. According to the one aspect of the present disclosure, it is possible to appropriately determine a DMRS port.

Description

Terminal, wireless communication method and base station

[0001] The present disclosure relates to a terminal, a wireless communication method, and a base station in a next-generation mobile communication system.

[0002] Long Term Evolution (LTE) has been specified for the Universal Mobile Telecommunications System (UMTS) network with the aim of achieving higher data rates and lower latency (Non-Patent Document 1). Also, LTE-Advanced (3GPP Rel. 10-14) has been specified with the aim of achieving higher capacity and more advanced features than LTE (Third Generation Partnership Project (3GPP (registered trademark)) Release (Rel.) 8, 9).

[0003] Successor systems to LTE (e.g., 5th generation mobile communication system (5G), 5G+ (plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel. 15 or later, etc.) are also being considered.

[0004] 3GPP TS 36.300 V8.12.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8)”, April 2010

[0005] For future wireless communication systems (e.g., Rel. 18 NR), a demodulation reference signal (DMRS) port for an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) that can support a number of layers greater than four is under consideration. Also, for Rel. 18 NR, increasing the number of orthogonal DMRS ports for the PUSCH / downlink shared channel (Physical Downlink Shared Channel (PDSCH)) is under consideration. Such new DMRS ports, which are different from existing DMRS ports (also referred to as Rel. 15 DMRS ports), are also referred to as Rel. 18 DMRS ports.

[0006] However, when Rel. 18 DMRS ports are introduced, sufficient consideration has not been given to how to designate antenna ports and how to switch between Rel. 15 DMRS ports. If these considerations are insufficient, DMRS port designation may not be performed appropriately, which may result in a decrease in communication throughput.

[0007] Therefore, one of the objects of the present disclosure is to provide a terminal, a wireless communication method, and a base station that can appropriately determine a DMRS port.

[0008] A terminal according to one aspect of the present disclosure includes: a receiving unit that receives Downlink Control Information (DCI) for scheduling an uplink shared channel; and a control unit that selects, based on a specific field of the DCI, an antenna port indication table related to demodulation reference signal (DMRS) port indication for the uplink shared channel from a plurality of tables for a certain rank.

[0009] According to one aspect of the present disclosure, the DMRS port can be appropriately determined.

[0010] Figure 1 shows an example of parameters for PDSCH DMRS. Figure 2 shows an example of parameters for PUSCH DMRS. Figures 3A-3D show an example of a table of referenced antenna ports when the transform precoder is disabled, the DMRS type is 1, and the maximum DMRS length is 1 in Rel. 15. Figures 4A-4D show an example of a table of referenced antenna ports when the transform precoder is disabled, the DMRS type is 1, and the maximum DMRS length is 2 in Rel. 15. Figures 5A-5D show an example of a table of referenced antenna ports when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 1 in Rel. 15. Figures 6A and 6B show an example of a table of referenced antenna ports when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 2 in Rel. 15. Figures 7A and 7B show an example of a table of referenced antenna ports when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 2 in Rel. 15. 15, when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 2. FIGS. 8A to 8D are diagrams showing examples of tables of antenna ports to be referenced when the transform precoder is disabled, the DMRS type is 1, and the maximum DMRS length is 2. FIGS. 9A and 9B are diagrams showing examples of tables of antenna ports to be referenced when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 1. FIGS. 10A to 10D are diagrams showing examples of tables of antenna ports to be referenced when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 2. FIGS. 11A and 11B are diagrams showing an example of the size of the antenna port field in the first embodiment. FIG. 12 is a diagram showing an example of the size of the antenna port field in the second embodiment. FIGS. 13A and 13B are diagrams showing an example of the size of the antenna port field in the second embodiment. FIG. 14 is a diagram showing an example of the size of the antenna port field in Rel. 15 shows an example of a table of antenna ports to be referenced for PDSCH DMRS when DMRS configuration type = 1 and maximum DMRS length = 1.Figure 15 is a diagram illustrating an example of parameters for DMRS configuration type 1 for Rel. 18 DMRS. Figure 16 is a diagram illustrating an example of parameters for DMRS configuration type 2 for Rel. 18 DMRS. Figure 17 is a diagram illustrating an example of a table of antenna ports referenced for PDSCH DMRS when DMRS configuration type = 1 and DMRS maximum length = 1 according to embodiment 3.1. Figure 18 is a diagram illustrating an example of a table of antenna ports referenced for PDSCH DMRS when DMRS configuration type = 1 and DMRS maximum length = 1 according to embodiment 3.1. Figure 19 is a diagram illustrating an example of a table of antenna ports referenced for PDSCH DMRS when DMRS configuration type = 1 and DMRS maximum length = 1 according to embodiment 3.2. Figure 20 is a diagram illustrating an example of a table of antenna ports referenced for PDSCH DMRS when DMRS configuration type = 1 and DMRS maximum length = 1 according to embodiment 3.2. 21 is a diagram illustrating an example of a table of antenna ports to be referenced for a PDSCH DMRS when the DMRS configuration type is 1 and the maximum DMRS length is 1 according to embodiment 3.3. FIG. 22 is a diagram illustrating an example of a table of antenna ports to be referenced for a PDSCH DMRS when the DMRS configuration type is 1 and the maximum DMRS length is 1 according to embodiment 3.3. FIG. 23A and 23B are diagrams illustrating an example of a correspondence relationship between values ​​in the antenna port field and corresponding DMRS ports for a DMRS port designation method 2 according to the third embodiment. FIG. 24A and 24B are diagrams illustrating an example of a correspondence relationship between values ​​in the antenna port field and corresponding DMRS ports for a DMRS port designation method 3 according to the third embodiment. FIG. 25A and 25B are diagrams illustrating an example of a correspondence relationship between values ​​in the antenna port field and corresponding DMRS ports for a DMRS port designation method 4 according to the third embodiment. FIG. 26 is a diagram illustrating an example of a table of antenna ports to be referred to for a PUSCH DMRS when the DMRS configuration type is 1, the maximum DMRS length is 1, and the rank is 1 according to embodiment 4.1.FIG. 27 is a diagram illustrating an example of a table of antenna ports to be referenced for a PUSCH DMRS when the DMRS configuration type is 1, the maximum DMRS length is 1, and the rank is 2 according to embodiment 4.1. FIG. 28 is a diagram illustrating an example of a table of antenna ports to be referenced for a PUSCH DMRS when the DMRS configuration type is 1, the maximum DMRS length is 1, and the rank is 3 according to embodiment 4.1. FIG. 29 is a diagram illustrating an example of a table of antenna ports to be referenced for a PUSCH DMRS when the DMRS configuration type is 1, the maximum DMRS length is 1, and the rank is 4 according to embodiment 4.1. FIG. 30 is a diagram illustrating an example of switching of an antenna port instruction table based on DCI according to a fifth embodiment. FIG. 31 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. FIG. 32 is a diagram illustrating an example of a configuration of a base station according to an embodiment. FIG. 33 is a diagram illustrating an example of a configuration of a user terminal according to an embodiment. FIG. 34 is a diagram illustrating an example of a hardware configuration of a base station and a user terminal according to an embodiment. FIG. 35 is a diagram illustrating an example of a vehicle according to an embodiment.

[0011] (Control of Transmission of SRS and PUSCH) In Rel. 15 NR, a terminal (user terminal, User Equipment (UE)) may receive information (SRS configuration information, for example, parameters in the RRC control element "SRS-Config") used for transmitting a measurement reference signal (for example, a sounding reference signal (SRS)).

[0012] Specifically, the UE may receive at least one of information regarding one or more SRS resource sets (SRS resource set information, e.g., the RRC control element "SRS-ResourceSet") and information regarding one or more SRS resources (SRS resource information, e.g., the RRC control element "SRS-Resource").

[0013] An SRS resource set may be associated with (or group together) a predetermined number of SRS resources, each of which may be identified by an SRS Resource Indicator (SRI) or SRS Resource Identifier (ID).

[0014] The SRS resource set information may include an SRS resource set ID (SRS-ResourceSetId), a list of SRS resource IDs (SRS-ResourceId) used in the resource set, an SRS resource type, and information on SRS usage.

[0015] Here, the SRS resource type may indicate any one of periodic SRS (P-SRS), semi-persistent SRS (SP-SRS), and aperiodic CSI (Aperiodic SRS (A-SRS)). Note that the UE may transmit the P-SRS and SP-SRS periodically (or periodically after activation), and transmit the A-SRS based on an SRS request in the downlink control information (Downlink Control Information (DCI)).

[0016] Furthermore, the use ("usage" of the RRC parameter, "SRS-SetUse" of the L1 (Layer-1) parameter) may be, for example, beam management, codebook (CB), non-codebook (NCB), antenna switching, etc. The SRS for codebook or non-codebook use may be used to determine a precoder for codebook-based or non-codebook-based uplink shared channel (Physical Uplink Shared Channel (PUSCH)) transmission based on the SRI.

[0017] For example, in the case of codebook-based transmission, the UE may determine a precoder (precoding matrix) for PUSCH transmission based on the SRI, transmission rank (which may simply be referred to as rank), and a Transmitted Precoding Matrix Indicator (TPMI). In the case of non-codebook-based transmission, the UE may determine a precoder for PUSCH transmission based on the SRI.

[0018] The SRS resource information may include an SRS resource ID (SRS-ResourceId), the number of SRS ports, the SRS port number, a transmission comb, an SRS resource mapping (e.g., time and / or frequency resource position, resource offset, resource period, number of repetitions, number of SRS symbols, SRS bandwidth, etc.), hopping-related information, an SRS resource type, a sequence ID, spatial relationship information of the SRS, etc.

[0019] The spatial relationship information of the SRS (e.g., the RRC information element "spatialRelationInfo") may indicate spatial relationship information between a predetermined reference signal and the SRS. The predetermined reference signal may be at least one of a Synchronization Signal / Physical Broadcast Channel (SS / PBCH) block, a Channel State Information Reference Signal (CSI-RS), and an SRS (e.g., another SRS). The SS / PBCH block may be referred to as a Synchronization Signal Block (SSB).

[0020] The spatial relationship information of the SRS may include at least one of an SSB index, a CSI-RS resource ID, and an SRS resource ID as an index of the predetermined reference signal.

[0021] In the present disclosure, the SSB index, SSB resource ID, and SSB Resource Indicator (SSBRI) may be interchangeable. Furthermore, the CSI-RS index, CSI-RS resource ID, and CSI-RS Resource Indicator (CRI) may be interchangeable. Furthermore, the SRS index, SRS resource ID, and SRI may be interchangeable.

[0022] The spatial relationship information of the SRS may include a serving cell index, a BWP index (BWP ID), etc. corresponding to the predetermined reference signal.

[0023] When the UE is configured with spatial relationship information regarding the SRS and an SSB or CSI-RS for a certain SRS resource, the UE may transmit the SRS resource using the same spatial domain filter (spatial domain transmit filter) as the spatial domain filter for receiving the SSB or CSI-RS (spatial domain receive filter). In this case, the UE may assume that the UE receive beam for the SSB or CSI-RS and the UE transmit beam for the SRS are the same.

[0024] When the UE is configured with spatial relationship information between another SRS (reference SRS) and the target SRS for a certain SRS (target SRS), the UE may transmit the target SRS resource using the same spatial domain filter (spatial domain transmit filter) as the spatial domain filter (spatial domain transmit filter) for transmitting the reference SRS. That is, in this case, the UE may assume that the UE transmit beam of the reference SRS and the UE transmit beam of the target SRS are the same.

[0025] The UE may determine the spatial relationship of the PUSCH scheduled by the DCI (e.g., DCI format 0_1) based on the value of a predetermined field (e.g., an SRS resource identifier (SRI) field) in the DCI. Specifically, the UE may use spatial relationship information of the SRS resources (e.g., the RRC information element "spatialRelationInfo") determined based on the value of the predetermined field (e.g., the SRI) for PUSCH transmission.

[0026] In Rel. 15 / 16 NR, when codebook-based transmission is used for PUSCH, the UE is configured by RRC with an SRS resource set of a codebook usage having up to two SRS resources, and one of the up to two SRS resources may be indicated by DCI (a 1-bit SRI field). The transmission beam for PUSCH is specified by the SRI field.

[0027] The UE may determine the TPMI and the number of layers (transmission rank) for the PUSCH based on the precoding information and number of layers field (hereinafter also referred to as the precoding information field). The UE may select a precoder from an uplink codebook for the same number of SRS ports as the number of SRS ports indicated by the upper layer parameter "nrofSRS-Ports" configured for the SRS resource specified by the SRI field based on the TPMI, the number of layers, etc.

[0028] In Rel. 15 / 16 NR, when non-codebook-based transmission is used for PUSCH, a non-codebook-used SRS resource set having up to four SRS resources may be configured for the UE by RRC, and one or more of the up to four SRS resources may be indicated by DCI (a 2-bit SRI field).

[0029] The UE may determine the number of layers (transmission rank) for the PUSCH based on the SRI field. For example, the UE may determine that the number of SRS resources specified by the SRI field is the same as the number of layers for the PUSCH. The UE may also calculate a precoder for the SRS resources.

[0030] If a CSI-RS (which may be referred to as an associated CSI-RS) associated with the SRS resource (or an SRS resource set to which the SRS resource belongs) is configured by a higher layer, the transmission beam for the PUSCH may be calculated based on (measurements of) the configured associated CSI-RS. Otherwise, the transmission beam for the PUSCH may be specified by the SRI.

[0031] The UE may be configured to use codebook-based PUSCH transmission or non-codebook-based PUSCH transmission by a higher layer parameter "txConfig" indicating a transmission scheme. The parameter may indicate a value of "codebook" or "non-codebook."

[0032] In the present disclosure, a codebook-based PUSCH (codebook-based PUSCH transmission, codebook-based transmission) may refer to a PUSCH when a UE is configured with "codebook" as a transmission scheme. In the present disclosure, a non-codebook-based PUSCH (non-codebook-based PUSCH transmission, non-codebook-based transmission) may refer to a PUSCH when a UE is configured with "non-codebook" as a transmission scheme.

[0033] (DMRS) The front-loaded DMRS is the first DMRS (at or near the first symbol) for faster demodulation. An additional DMRS can be configured by RRC for fast-moving UEs or high modulation and coding scheme (MCS) / rank. The frequency location of the additional DMRS is the same as that of the front-loaded DMRS.

[0034] For the time domain, DMRS mapping type A or B is configured. In DMRS mapping type A, DMRS position l_0 is counted by the symbol index within the slot. l_0 is configured by the parameter (dmrs-TypeA-Position) in the MIB or common serving cell configuration (ServingCellConfigCommon). DMRS position 0 (reference point l) refers to the first symbol of the slot or each frequency hop. In DMRS mapping type B, DMRS position l_0 is counted by the symbol index within the PDSCH / PUSCH. l_0 is always 0. DMRS position 0 (reference point l) refers to the first symbol of the PDSCH / PUSCH or each frequency hop.

[0035] The DMRS location is defined by a table in the specification and depends on the duration of the PDSCH / PUSCH. The location of the additional DMRS is fixed.

[0036] For the frequency domain, (PDSCH / PUSCH) DMRS configuration type 1 or type 2 is configured. DMRS configuration type 1 has a comb structure and is applicable to both Cyclic Prefix Orthogonal Frequency Division Multiplexing (CP-OFDM) and Discrete Fourier Transform Spread OFDM (DFT-s-OFDM). DMRS configuration type 2 is applicable only to CP-OFDM.

[0037] Note that CP-OFDM may be used when transform precoding (which may also be referred to as a transform precoder) is disabled (the parameter of the transform precoder (e.g., transformPrecoder) = "disabled"), and DFT-S-OFDM may be used when the parameter of the transform precoder (e.g., transformPrecoder) = "enabled").

[0038] Single symbol DMRS or double symbol DMRS may be configured in the UE.

[0039] Single-symbol DMRS is normally used (it is a mandatory feature in Rel. 15). In single-symbol DMRS, the number of additional DMRS (symbols) is {0, 1, 2, 3}. Single-symbol DMRS supports both frequency hopping enabled and disabled. If the maximum number (maxLength) in the uplink DMRS configuration (DMRS-UplinkConfig) is not configured, single-symbol DMRS is used.

[0040] Double-symbol DMRS is used for more DMRS ports (especially MU-MIMO). In double-symbol DMRS, the number of additional DMRS (symbols) is {0, 1}. Double-symbol DMRS is supported when frequency hopping is disabled. If the maximum number (maxLength) in the uplink DMRS configuration (DMRS-UplinkConfig) is 2 (len2), whether single-symbol DMRS or double-symbol DMRS is used is determined by the DCI or configured grant.

[0041] From the above, the possible DMRS configuration patterns are the following combinations: DMRS configuration type 1, DMRS mapping type A, single symbol DMRS DMRS configuration type 1, DMRS mapping type A, double symbol DMRS DMRS configuration type 1, DMRS mapping type B, single symbol DMRS DMRS configuration type 1, DMRS mapping type B, double symbol DMRS DMRS configuration type 2, DMRS mapping type A, single symbol DMRS DMRS configuration type 2, DMRS mapping type A, double symbol DMRS DMRS configuration type 2, DMRS mapping type B, single symbol DMRS DMRS configuration type 2, DMRS mapping type B, double symbol DMRS

[0042] Multiple DMRS ports that are mapped to the same RE (time and frequency resource) are called a DMRS CDM group.

[0043] For DMRS configuration type 1 and single-symbol DMRS, four DMRS ports can be used. Within each DMRS CDM group, two DMRS ports are multiplexed using FD OCC of length 2. Between multiple DMRS CDM groups (two DMRS CDM groups), two DMRS ports are multiplexed using FDM.

[0044] For DMRS configuration type 1 and double-symbol DMRS, eight DMRS ports can be used. Within each DMRS CDM group, two DMRS ports are multiplexed by an FD OCC of length 2, and two DMRS ports are multiplexed by a TD OCC. Between multiple DMRS CDM groups (two DMRS CDM groups), two DMRS ports are multiplexed by FDM.

[0045] For DMRS configuration type 2 and single-symbol DMRS, six DMRS ports can be used. Within each DMRS CDM group, two DMRS ports are multiplexed using an FD OCC of length 2. Between multiple DMRS CDM groups (three DMRS CDM groups), three DMRS ports are multiplexed using FDM.

[0046] For DMRS configuration type 2 and double-symbol DMRS, 12 DMRS ports can be used. Within each DMRS CDM group, two DMRS ports are multiplexed by an FD OCC of length 2, and two DMRS ports are multiplexed by a TD OCC. Between multiple DMRS CDM groups (three DMRS CDM groups), three DMRS ports are multiplexed by FDM.

[0047] Here, an example of DMRS mapping type B is shown, but DMRS mapping type A is also similar.

[0048] 1 is a diagram illustrating an example of parameters for PDSCH DMRS. For DMRS configuration type 1, DMRS ports 1000-1007 can be used, and for DMRS configuration type 2, DMRS ports 1000-1011 can be used.

[0049] 2 is a diagram illustrating an example of parameters for PUSCH DMRS. For DMRS configuration type 1, DMRS ports 0-7 can be used, and for DMRS configuration type 2, DMRS ports 0-11 can be used.

[0050] (Ports of Reference Signals) For orthogonalization of MIMO layers, reference signals of multiple ports (for example, demodulation reference signals (DMRS) and CSI-RS) are used.

[0051] For example, for single user MIMO (SU-MIMO), a different DMRS port / CSI-RS port may be set for each layer. For multi user MIMO (MU-MIMO), a different DMRS port / CSI-RS port may be set for each layer within one UE and for each UE.

[0052] In addition, if the number of CSI-RS ports is greater than the number of layers used for data, it is possible to measure the channel state more accurately based on this CSI-RS, which is expected to contribute to improving throughput.

[0053] In Rel. 15 NR, multiple-port DMRS is supported using frequency division multiplexing (FDM), frequency domain orthogonal cover code (FD-OCC), time domain OCC (TD-OCC), etc., with up to eight ports for Type 1 DMRS (i.e., DMRS configuration type 1) and up to 12 ports for Type 2 DMRS (i.e., DMRS configuration type 2).

[0054] In Rel. 15 NR, a comb-like transmission frequency pattern (comb-like resource set) is used for the FDM. Cyclic Shift (CS) is used for the FD-OCC. Furthermore, the TD-OCC can only be applied to double-symbol DMRS.

[0055] The OCC in the present disclosure may be interchangeably read as orthogonal code, orthogonalization, cyclic shift, and the like.

[0056] The type of DMRS may be referred to as a DMRS configuration type.

[0057] Among DMRSs, DMRSs that are resource mapped in units of two consecutive (adjacent) symbols may be called double-symbol DMRSs, and DMRSs that are resource mapped in units of one symbol may be called single-symbol DMRSs.

[0058] Either DMRS may be mapped to one or more symbols per slot depending on the length of the data channel. A DMRS mapped to the beginning of a data symbol may be called a front-loaded DMRS, and a DMRS additionally mapped to other positions may be called an additional DMRS.

[0059] In the case of DMRS configuration type 1 and single-symbol DMRS, Comb and CS may be used for orthogonalization. For example, up to four antenna ports (APs) may be supported by using two types of Comb and two types of CS (Comb2+2CS).

[0060] In the case of DMRS configuration type 1 and double-symbol DMRS, the comb, CS, and TD-OCC may be used for orthogonalization. For example, up to eight APs may be supported using two types of comb, two types of CS, and TD-OCC ({1,1} and {1,-1}).

[0061] In the case of DMRS configuration type 2 and single-symbol DMRS, FD-OCC may be used for orthogonalization. For example, up to six APs may be supported by applying an orthogonal code (2-FD-OCC) to two adjacent resource elements (REs) in the frequency direction.

[0062] In the case of DMRS configuration type 2 and double-symbol DMRS, FD-OCC and TD-OCC may be used for orthogonalization. For example, up to 12 APs may be supported by applying an orthogonal code (2-FD-OCC) to two adjacent REs in the frequency direction and a TD-OCC ({1,1} and {1,-1}) to two adjacent REs in the time direction.

[0063] In addition, in Rel. 15 NR, a maximum of 32 ports of the multi-port CSI-RS are supported by using FDM, time division multiplexing (TDM), frequency domain OCC, time domain OCC, etc. The same method as that for the above-mentioned DMRS may also be applied to orthogonalization of the CSI-RS.

[0064] Now, a group of DMRS ports orthogonalized by the FD-OCC / TD-OCC as described above is also called a Code Division Multiplexing (CDM) group.

[0065] Different CDM groups are orthogonal because they are FDM-encoded. However, within the same CDM group, the orthogonality of the applied OCC may be lost due to channel fluctuations, etc. In this case, if signals within the same CDM group are received with different reception powers, a near-far problem may occur, and orthogonality may not be guaranteed.

[0066] Here, we will explain the TD-OCC / FD-OCC of DMRS in Rel. 15 NR. The DMRS mapped to a resource element (RE) is a DMRS sequence with FD-OCC parameters (which may also be called sequence elements) w ｆ (k') and the TD-OCC parameters (which may also be called sequence elements) w ｔ (l') and may correspond to a sequence obtained by multiplying (l') and (l').

[0067] The TD-OCC and FD-OCC of the DMRS of Rel. 15 NR both correspond to OCCs with a sequence length (which may also be referred to as the OCC length) of 2. Therefore, the possible values ​​of k' and l' above are both 0 and 1. By multiplying this FD-OCC in RE units, two-port DMRS can be multiplexed using the same time and frequency resources (2 RE). When both the FD-OCC and TD-OCC are applied, four-port DMRS can be multiplexed using the same time and frequency resources (4 RE).

[0068] The two existing DMRS port tables for PDSCH shown in Fig. 1 correspond to DMRS configuration type 1 and type 2, respectively. Note that p indicates the antenna port number, and Δ indicates a parameter for shifting (offsetting) the frequency resource.

[0069] For example, for antenna ports 1000 and 1001, {w ｆ (0), w ｆ (1)} = {+1, +1} and {w ｆ (0), w ｆ (1)}={+1, -1} is applied to the vectors, and the vectors are orthogonalized using FD-OCC.

[0070] FDM is applied to antenna ports 1000-1001 and antenna ports 1002-1003 (and also antenna ports 1004-1005 in the case of Type 2) by applying different values ​​of Δ. Thus, antenna ports 1000-1003 (or 1000-1005) corresponding to single-symbol DMRS are orthogonalized using FD-OCC and FDM.

[0071] For the antenna ports 1000-1003 and the antenna ports 1004-1007 of type 1, {w ｔ (0), w ｔ (1)} = {+1, +1} and {w ｔ (0), w ｔ (1)}={+1, −1} is applied, and thus the antenna ports 1000-1007 (or 1000-1011) corresponding to the double-symbol DMRS are orthogonalized using FD-OCC, TD-OCC, and FDM.

[0072] For CP-OFDM only, it is considered to specify a larger number of orthogonal DMRS ports for DL / UL MU-MIMO (without increasing DMRS overhead), a common design between DL and UL DMRS, up to 24 orthogonal DMRS ports, and doubling the maximum number of orthogonal DMRS ports for both single-symbol DMRS and double-symbol DMRS for each applicable DMRS configuration type.

[0073] In Rel. 15, the following Cases 1 to 4 can be configured. [Case 1] The total number of single-symbol DMRS ports in DMRS configuration type 1 is 2 (by comb / FDM) × (by FD OCC) 2 = 4 ports. [Case 2] The total number of double-symbol DMRS ports in DMRS configuration type 1 is 2 (by comb / FDM) × (by FD OCC) 2 × (by TD OCC) 2 = 8 ports. [Case 3] The total number of single-symbol DMRS ports in DMRS configuration type 2 is 3 (by FDM) × (by FD OCC) 2 = 6 ports. [Case 4] The total number of double-symbol DMRS ports in DMRS configuration type 2 is 3 (by comb) × (by FD OCC) 2 × (by TD OCC) 2 = 12 ports.

[0074] Furthermore, in Cases 1 to 4 of Rel. 15, the mapping of CDM groups and DMRS port indices is as follows:

[0075] [Case 1] Four ports and two CDM groups may be available. For the PUSCH, CDM group #0 may correspond to DMRS port indices {0,1}, and CDM group #1 may correspond to DMRS port indices {2,3}. For the PDSCH, CDM group #0 may correspond to DMRS port indices {1000,1001}, and CDM group #1 may correspond to DMRS port indices {1002,1003}.

[0076] [Case 2] Eight ports and two CDM groups may be available. For the PUSCH, CDM group #0 may correspond to DMRS port indices {0, 1, 4, 5}, and CDM group #1 may correspond to DMRS port indices {2, 3, 6, 7}. For the PDSCH, CDM group #0 may correspond to DMRS port indices {1000, 1001, 1004, 1005}, and CDM group #1 may correspond to DMRS port indices {1002, 1003, 1006, 1007}.

[0077] [Case 3] Six ports and three CDM groups may be available. For the PUSCH, CDM group #0 may correspond to DMRS port index {0,1}, CDM group #1 may correspond to DMRS port index {2,3}, and CDM group #2 may correspond to DMRS port index {4,5}. For the PDSCH, CDM group #0 may correspond to DMRS port index {1000,1001}, CDM group #1 may correspond to DMRS port index {1002,1003}, and CDM group #2 may correspond to DMRS port index {1004,1005}.

[0078] [Case 4] 12 ports and 3 CDM groups may be available. For the PUSCH, CDM group #0 may correspond to DMRS port indices {0, 1, 6, 7}, CDM group #1 may correspond to DMRS port indices {2, 3, 8, 9}, and CDM group #2 may correspond to DMRS port indices {4, 5, 10, 11}. For the PDSCH, CDM group #0 may correspond to DMRS port indices {1000, 1001, 1006, 1007}, CDM group #1 may correspond to DMRS port indices {1002, 1003, 1008, 1009}, and CDM group #2 may correspond to DMRS port indices {1004, 1005, 1010, 1011}.

[0079] 3A-3D are diagrams illustrating examples of tables of antenna ports to be referenced when the transform precoder is disabled, the DMRS type is 1, and the maximum DMRS length is 1 in Rel. 15.

[0080] 3A is an example of a table of antenna ports corresponding to rank 1. In this example, different sets of DMRS ports (number of antenna ports: 1) are associated with the values ​​0 to 5 of the "Antenna ports" field.

[0081] 3B is an example of a table of antenna ports corresponding to rank 2. In this example, different sets of DMRS ports (number of antenna ports: 2) are associated with the values ​​0 to 3 in the antenna port field.

[0082] 3C is an example of a table of antenna ports corresponding to rank 3. In this example, a value of 0 in the antenna port field is associated with a different set of DMRS ports (number of antenna ports: 3).

[0083] 3D is an example of a table of antenna ports corresponding to rank 4. In this example, a value of 0 in the antenna port field is associated with a different set of DMRS ports (number of antenna ports: 4).

[0084] 4A to 4D are diagrams illustrating examples of tables of antenna ports to be referenced when the transform precoder is disabled, the DMRS type is 1, and the maximum DMRS length is 2 in Rel.

[0085] 4A is an example of a table of antenna ports corresponding to rank 1. In this example, different sets of DMRS ports (number of antenna ports: 1) are associated with the values ​​of the antenna port field = 0 to 13. Note that the correspondence between values ​​and entry contents is not limited to this. Other examples are similar.

[0086] 4B is an example of a table of antenna ports corresponding to rank 2. In this example, different sets of DMRS ports (number of antenna ports: 2) are associated with the values ​​0 to 9 in the antenna port field.

[0087] 4C is an example of a table of antenna ports corresponding to rank 3. In this example, different sets of DMRS ports (number of antenna ports: 3) are associated with the values ​​0 to 2 in the antenna port field.

[0088] 4D is an example of a table of antenna ports corresponding to rank 4. In this example, different sets of DMRS ports (number of antenna ports: 4) are associated with the values ​​0 to 3 in the antenna port field.

[0089] 5A to 5D are diagrams illustrating examples of tables of antenna ports to be referenced when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 1 in Rel.

[0090] 5A is an example of a table of antenna ports corresponding to rank 1. In this example, different sets of DMRS ports (number of antenna ports: 1) are associated with the values ​​of the antenna port field = 0 to 11. Note that the correspondence between values ​​and entry contents is not limited to this. Other examples are similar.

[0091] 5B is an example of a table of antenna ports corresponding to rank 2. In this example, different sets of DMRS ports (number of antenna ports: 2) are associated with the values ​​0 to 6 in the antenna port field.

[0092] 5C is an example of a table of antenna ports corresponding to rank 3. In this example, different sets of DMRS ports (number of antenna ports: 3) are associated with the values ​​0 to 2 in the antenna port field.

[0093] 5D is an example of a table of antenna ports corresponding to rank 4. In this example, different sets of DMRS ports (number of antenna ports: 4) are associated with the values ​​of the antenna port field = 0 to 1, respectively.

[0094] 6A, 6B, 7A, and 7B are diagrams illustrating examples of tables of antenna ports to refer to when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 2 in Rel.

[0095] 6A is an example of a table of antenna ports corresponding to rank 1. In this example, different sets of DMRS ports (number of antenna ports: 1) are associated with the values ​​0 to 27 in the antenna port field.

[0096] 6B is an example of a table of antenna ports corresponding to rank 2. In this example, different sets of DMRS ports (number of antenna ports: 2) are associated with the values ​​0 to 18 in the antenna port field.

[0097] 7A is an example of a table of antenna ports corresponding to rank 3. In this example, different sets of DMRS ports (number of antenna ports: 3) are associated with the values ​​0 to 5 in the antenna port field.

[0098] 7B is an example of a table of antenna ports corresponding to rank 4. In this example, different sets of DMRS ports (number of antenna ports: 4) are associated with the values ​​0 to 4 in the antenna port field.

[0099] <DMRS Ports for Layers with Number Greater Than Four Layers> An example of a table of antenna ports for DMRS port indication for layers with number greater than four when the transform precoder is disabled will be described.

[0100] For a codebook-based PUSCH, the UE determines the rank (number of layers) for PUSCH transmission based on the precoding information field of the DCI. For a non-codebook-based PUSCH, the UE determines the rank (number of layers) for PUSCH transmission based on the SRS resource indicator field of the DCI.

[0101] The UE may then determine the table of antenna ports corresponding to the determined rank based on whether the transform precoder is enabled or disabled, the DMRS type of the PUSCH set by higher layer signaling (which may be set by the RRC parameter "dmrs-Type"), and the value of the maximum length of the DMRS (which may be set by the RRC parameter "maxLength").

[0102] In addition, the value of the antenna port field of the DCI may determine the table entry to be referenced (the entry corresponds to a set such as the number of CDM groups, the antenna port index of the DMRS, and the number of front-load symbols).

[0103] [When DMRS type=1, max DMRS length=1] When DMRS type=1, max DMRS length=1, transmissions up to rank 4 may be supported. In other words, a UE configured with DMRS type=1 and max DMRS length=1 may not support transmissions greater than rank 4.

[0104] [When DMRS type=1, maximum DMRS length=2] When DMRS type=1, maximum DMRS length=2, transmissions up to rank 8 may be supported.

[0105] 8A-8D are diagrams showing examples of tables of antenna ports to refer to when the transform precoder is disabled, the DMRS type is 1, and the maximum DMRS length is 2.

[0106] 8A is an example of a table of antenna ports corresponding to rank 5. In this example, different sets of DMRS ports (number of antenna ports: 5) are associated with the values ​​of the antenna port field = 0 to 3. Note that the correspondence between values ​​and entry contents is not limited to this. Other examples are similar.

[0107] In Figure 8A, 2+3 layers and 3+2 layers may be supported. Note that only some of the illustrated entries may be supported. For example, only the entries for DMRS ports 0-4 may be supported for the 2+3 layer, and only the entries for DMRS ports 0, 1, 2, 3, and 6 may be supported for the 3+2 layer.

[0108] 8B is an example of a table of antenna ports corresponding to rank 6. In this example, different sets of DMRS ports (6 antenna ports) are associated with the values ​​0 to 2 in the antenna port field.

[0109] In Figure 8B, 4+2 layers, 2+4 layers, and 3+3 layers may be supported, although only certain X, Y combinations (e.g., 3+3) for X+Y layers may be supported.

[0110] 8C is an example of a table of antenna ports corresponding to rank 7. In this example, different sets of DMRS ports (7 antenna ports) are associated with the values ​​0 to 1 in the antenna port field.

[0111] In Figure 8C, 4+3 and 3+4 layers may be supported.

[0112] 8D is an example of a table of antenna ports corresponding to rank 8. In this example, a set of DMRS ports (number of antenna ports: 8) is associated with a value of 0 in the antenna port field.

[0113] In FIG. 8D, only 4+4 layers may be supported.

[0114] [When DMRS type = 2, maximum DMRS length = 1] When DMRS type = 2, maximum DMRS length = 1, transmission up to rank 6 may be supported, or only transmission up to rank 4 may be supported, or transmission of rank 6 (e.g., 4+2 layers) may not be supported and only transmission up to rank 5 may be supported.

[0115] 9A and 9B are diagrams showing examples of tables of antenna ports to refer to when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 1.

[0116] 9A is an example of a table of antenna ports corresponding to rank 5. In this example, a set of DMRS ports (number of antenna ports: 5) is associated with a value of 0 in the antenna port field.

[0117] 9B is an example of a table of antenna ports corresponding to rank 6. In this example, a set of DMRS ports (number of antenna ports: 6) is associated with a value of 0 in the antenna port field.

[0118] [When DMRS type=2, maximum DMRS length=2] When DMRS type=2, maximum DMRS length=2, transmissions up to rank 8 may be supported.

[0119] 10A-10D are diagrams showing examples of tables of antenna ports to refer to when the transform precoder is disabled, the DMRS type is 2, and the maximum DMRS length is 2.

[0120] 10A is an example of a table of antenna ports corresponding to rank 5. In this example, different sets of DMRS ports (number of antenna ports: 5) are associated with the values ​​0 to 2 in the antenna port field.

[0121] 10B is an example of a table of antenna ports corresponding to rank 6. In this example, different sets of DMRS ports (6 antenna ports) are associated with the values ​​0 to 3 in the antenna port field.

[0122] In Figure 10B, 4+2 layers, 2+4 layers, and 3+3 layers may be supported. Note that only specific X, Y combinations (e.g., 3+3) for X+Y layers may be supported. For example, only the entry corresponding to the value of the antenna port field in Figure 8B = 3 may be supported for 3+3.

[0123] 10C is an example of a table of antenna ports corresponding to rank 7. In this example, different sets of DMRS ports (7 antenna ports) are associated with the values ​​0 to 2 in the antenna port field.

[0124] 10D is an example of a table of antenna ports corresponding to rank 8. In this example, a set of DMRS ports (number of antenna ports: 8) is associated with values ​​0 to 2 in the antenna port field.

[0125] For FIG. 10D, only entries corresponding to the 4+4 layer may be supported.

[0126] According to the DMRS port indication for the number of layers greater than four as described above, it is possible to appropriately specify antenna ports for a PUSCH using the number of layers greater than four when the transform precoder is disabled.

[0127] (Analysis) As described above, DMRS ports that can support a number of layers greater than four are being considered for Rel. 18 NR. Also, for Rel. 18 NR, increasing the number of orthogonal DMRS ports for PUSCH / PDSCH is being considered. Such new DMRS ports, which differ from existing DMRS ports (also called Rel. 15 DMRS ports), are also called Rel. 18 DMRS ports.

[0128] However, when Rel. 18 DMRS ports are introduced, sufficient consideration has not been given to how to designate antenna ports and how to switch between Rel. 15 DMRS ports. If these considerations are insufficient, DMRS port designation may not be performed appropriately, which may result in a decrease in communication throughput.

[0129] Therefore, the present inventors have devised a method for appropriately determining the DMRS port.

[0130] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. Wireless communication methods according to the embodiments may be applied independently or in combination.

[0131] In the present disclosure, "A / B" and "at least one of A and B" may be interpreted interchangeably. Also, in the present disclosure, "A / B / C" may mean "at least one of A, B, and C."

[0132] In the present disclosure, terms such as notify, activate, deactivate, indicate (or indicate), select, configure, update, and determine may be read interchangeably. In the present disclosure, terms such as support, control, controllable, operate, and operate may be read interchangeably.

[0133] In the present disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, higher layer parameters, fields, information elements (IEs), settings, etc. may be interchangeable. In the present disclosure, Medium Access Control (MAC) control elements (CEs), update commands, activation / deactivation commands, etc. may be interchangeable.

[0134] In the present disclosure, higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, etc., or a combination thereof.

[0135] In the present disclosure, MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. Broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0136] In the present disclosure, physical layer signaling may be, for example, Downlink Control Information (DCI), Uplink Control Information (UCI), and the like.

[0137] In the present disclosure, the terms index, identifier (ID), indicator, resource ID, etc. may be interchangeable. In the present disclosure, the terms sequence, list, set, group, cluster, subset, etc. may be interchangeable.

[0138] In the present disclosure, the terms panel, UE panel, panel group, beam, beam group, precoder, Uplink (UL) transmitting entity, Transmission / Reception Point (TRP), base station, Spatial Relation Information (SRI), spatial relation, SRS Resource Indicator (SRI), Control Resource Set (CORESET), Physical Downlink Shared Channel (PDSCH), Codeword (CW), Transport Block (TB), Reference Signal (RS), antenna port (e.g., Demodulation Reference Signal (DMRS) port), antenna port group (e.g., DMRS port group), group (e.g., spatial relation group, Code Division Multiplexing (CDM) group, reference signal group, CORESET group, Physical Uplink Control Channel (PUCCH) group, PUCCH resource group), resource (e.g., reference signal resource, SRS resource), resource set (e.g., reference signal resource set), CORESET pool, downlink Transmission Configuration Indication state (TCI state) (DL TCI state), uplink TCI state (UL TCI state), unified TCI state, common TCI state, Quasi-Co-Location (QCL), QCL assumption, etc. may be read as interchangeable.

[0139] In this disclosure, the notation "Rel. XX" indicates a 3GPP release. However, the release number "XX" is an example and may be replaced with another number.

[0140] In the present disclosure, DMRS, DL DMRS, UL DMRS, PDSCH DMRS, and PUSCH DMRS may be read as interchangeable terms.

[0141] In the present disclosure, orthogonal sequence, OCC, FD OCC, and TD OCC may be interpreted as interchangeable.

[0142] In the present disclosure, the terms DMRS port, antenna port, port, and DMRS port index may be interchangeable. In the present disclosure, the terms DMRS CDM group, CDM group, DMRS group, DMRS CDM group(s) without data, etc. may be interchangeable. In the present disclosure, the terms antenna port indication and antenna port field may be interchangeable. In the present disclosure, the terms DMRS configuration type and DMRS type may be interchangeable. In the present disclosure, the terms maximum DMRS length and number of DMRS symbols may be interchangeable.

[0143] In the present disclosure, the terms CDM group list, port group list, and list may be interchangeable. In the present disclosure, the terms CDM group subset, port group subset, and group subset may be interchangeable.

[0144] In the present disclosure, the terms rank, transmission rank, number of layers, and number of antenna ports may be interchangeable. Furthermore, the terms "one codeword is applied" and "the number of layers is four or less" may be interchangeable. The terms "two codewords are applied" and "the number of layers is greater than four" may be interchangeable.

[0145] In the present disclosure, "transform precoding is configured" may be read interchangeably as "transform precoding is enabled."

[0146] It should be noted that in this disclosure, "having the capability of..." may be read interchangeably as "supporting / reporting the capability of...".

[0147] In the present disclosure, a table may be read interchangeably as one or more tables.

[0148] Furthermore, DCI in the following embodiments may refer to DCI that schedules at least one of PUSCH and PDSCH (for example, DCI formats 0_x, 1_x (where x is an integer)).

[0149] (Wireless communication method) <First embodiment> The first embodiment relates to switching (selection, determination) of a table of antenna ports for DMRS port indication (hereinafter also referred to as an antenna port indication table, a DMRS port indication table, a DMRS port table, etc.) based on a specific field of DCI.

[0150] In the first embodiment, the UE may determine (or be specified) which table to use to look up the antenna port field from one of the antenna port indication tables for Rel. 15 DMRS ports (e.g., the tables in FIGS. 4A-4D) and the antenna port indication tables for Rel. 18 DMRS ports (e.g., the tables in FIGS. 8A-8D) based on the value of a specific field.

[0151] Hereinafter, for simplicity, in this disclosure, the antenna port indication table for Rel. 15 DMRS ports will also be referred to as the Rel. 15 table (or first table), and the antenna port indication table for Rel. 18 DMRS ports will also be referred to as the Rel. 18 table (or second table). In the case of PUSCH DMRS, the Rel. 15 table may be, for example, (at least one of) the tables for ranks 1-4 shown in Figures 3-6, and the Rel. 18 table may be, for example, but not limited to, (at least one of) the tables for ranks 5-8 shown in Figures 7-10.

[0152] In this disclosure, a Rel. 18 table may refer to a table that can be referenced separately from a Rel. 15 table referenced in Rel. 15 for a certain set of parameters (e.g., DMRS configuration (e.g., DMRS configuration type, DMRS mapping type, DMRS maximum length, single / double symbol DMRS) and PUSCH / PDSCH configuration (transform precoder, number of codewords, rank, etc.)).

[0153] For example, a Rel. 18 table for PUSCH DMRS may refer to a different table than the table specified in Rel. 15 (Rel. 15 table) that is available for a certain transform precoder enable / disable setting, a certain DMRS configuration type, a certain DMRS maximum length, and a certain rank.

[0154] For example, in the present disclosure, a Rel. 18 table for PUSCH DMRS may refer only to an antenna port indication table for DMRS ports for rank 5 or higher (e.g., number of layers 5-8) where the maximum number of DMRS ports is the same as that of Rel. 15, or may refer only to an antenna port indication table for DMRS ports for any rank (e.g., at least one of number of layers 1-8) where the maximum number of DMRS ports is n times (e.g., n = 2, 3, 4, ...) that of the same DMRS configuration (e.g., DMRS configuration type, DMRS mapping type, single / double symbol DMRS) in Rel. 15, or may refer to both of these tables. n may be predetermined by a standard or configured in the UE by higher layer signaling.

[0155] Note that the UE may be configured to apply the n-fold maximum number of DMRS ports of Rel. 15 by higher layer signaling (e.g., RRC / MAC CE) or may be specified by DCI (e.g., the above-mentioned specific field).

[0156] The specific field may be at least one of the following: (1) a new field that is not included in an existing (e.g., Rel. 17 NR) DCI field (e.g., it may be called an antenna port indication table field, a maximum number of antenna ports field, etc.); (2) a precoding information field / SRI field; (3) one or more existing (e.g., Rel. 17 NR) DCI fields.

[0157] Regarding (1) above, for example, a value of 0 in the antenna port indication table field may indicate a Rel. 15 table (or the maximum number of antenna ports is the same as that of Rel. 15), and a value of 1 in the antenna port indication table field may indicate a Rel. 18 table (or the maximum number of antenna ports is n times that of Rel. 15).

[0158] Regarding (2) above, the UE may determine the antenna port indication table based on a result of comparing the rank value determined based on the precoding information field / SRI field with a specific value (e.g., 4). For example, the UE may refer to the Rel. 18 table if the determined rank value is greater than the specific value, and may refer to the Rel. 15 table if the determined rank value is equal to or less than the specific value.

[0159] Regarding (3) above, if the bit sequences of some or all of one or more existing DCI fields correspond to specific (special) bit sequences, the UE may refer to the Rel. 18 table, and if not, may refer to the Rel. 15 table.

[0160] For example, the value of a specific bit (e.g., the most significant bit / the least significant bit) of the antenna port field may be used to switch between Rel. 15 and Rel. 18 tables. In this case, the size of the antenna port field may be extended by x bits (e.g., x = 1) compared to the case of the same DMRS configuration (DMRS configuration type, maximum DMRS length, etc.) / same PUSCH (PDSCH) configuration (number of codewords, etc.) in Rel. 15 / 16.

[0161] Note that the size of the antenna port field may be the same regardless of the value of the specific field, or may vary according to the value of the specific field. In the former case, if the largest index (largest "Value" value) included in the Rel. 15 table and the largest index (largest "Value" value) included in the Rel. 18 table are different, the UE may determine that reserved bits (which may also be called padding bits) are added to the antenna port field for the table with the smaller largest index until it has the same size as the antenna port field for the other table. This maintains the size of the DCI regardless of the value of the specific field, allowing the UE to monitor the same search space to detect the DCI.

[0162] 11A and 11B are diagrams showing an example of the size of the antenna port field in the first embodiment. In this example, a Rel. 15 table or a Rel. 18 table is switched by DCI. The antenna port field included in the DCI corresponds to the antenna port field for the Rel. 15 table or the Rel. 18 table specified by the DCI.

[0163] Figure 11A shows a case where the size of the antenna port field for the Rel. 15 table and the size of the antenna port field for the Rel. 18 table are the same. Figure 11B shows a case where the size of the antenna port field for the Rel. 15 table is smaller than the size of the antenna port field for the Rel. 18 table. In the case of Figure 11B, the antenna port field for the Rel. 15 table may be composed of a bit string including reserved bits.

[0164] Note that the UE may perform the above-mentioned bit padding of the antenna port field only when information enabling dynamic switching of the antenna port indication table is configured by higher layer signaling. This is because if dynamic switching is not required, there is no need to align the sizes of the antenna port field for the Rel. 15 table and the antenna port field for the Rel. 18 table. By not performing bit padding, a smaller DCI size can be achieved.

[0165] According to the first embodiment described above, the antenna port instruction table can be dynamically switched based on the DCI.

[0166] Second Embodiment The second embodiment relates to switching of the antenna port indication table based on higher layer signaling (for example, RRC signaling, MAC CE).

[0167] In a second embodiment, the UE may determine (or be specified) which table to use for referencing the antenna port field from one of the Rel. 15 table and the Rel. 18 table based on higher layer signaling. For example, the higher layer signaling may indicate (or enable) any of the following: Rel. 15 DMRS port (or Rel. 15 table), Rel. 18 DMRS port (or Rel. 18 table), or dynamic switching (or both Rel. 15 DMRS port (or Rel. 15 table) and Rel. 18 DMRS port (or Rel. 18 table)).

[0168] Based on the configuration of the higher layer signaling, the UE may determine the size of the antenna port field included in the DCI.

[0169] 12 is a diagram illustrating an example of the size of the antenna port field in the second embodiment. In this example, the RRC configures the UE with either the Rel. 15 DMRS port, the Rel. 18 DMRS port, or dynamic switching.

[0170] The UE may determine that if a Rel. 15 DMRS port is configured, the antenna port field is the antenna port field for the Rel. 15 table and is A bits in size (A is an integer).

[0171] The UE may determine that if a Rel. 18 DMRS port is configured, the antenna port field is the antenna port field for the Rel. 18 table and is B bits in size (B is an integer).

[0172] The UE may determine that if dynamic switching is configured, the antenna port field is the antenna port field for the Rel. 15 table and the Rel. 18 table and has a size of A'+B' bits (A' and B' are integers).

[0173] Note that A' and A may be the same or different. If they are different, the Rel. 15 table that can be specified by a bit string of size A' may correspond to a portion of the Rel. 15 table that can be specified by a bit string of size A (for example, a table in which some of the columns (entries) containing "Reserved" are omitted).

[0174] Furthermore, B' and B may be the same or different. If they are different, the Rel. 18 table that can be specified by a bit string of size B' may correspond to a portion of the Rel. 18 table that can be specified by a bit string of size B (for example, a table in which some columns (entries) containing "Reserved" are omitted).

[0175] 13A and 13B are diagrams illustrating an example of the size of the antenna port field in the second embodiment. In this example, the dynamic switching described above is configured for the UE by the RRC. Also, in this example, consider the case where the transform precoder is disabled, the DMRS type is 1, the maximum DMRS length is 2, the Rel. 15 tables are shown in FIGS. 4A-4D, and the Rel. 18 tables are shown in FIGS. 8A-8D.

[0176] Figure 13A corresponds to the case in Figure 12 where A' = A and B' = B. Because A = B = 4 bits, the antenna port field in Figure 13A is 4 + 4 = 8 bits. However, as shown in Figures 4A-4D, the maximum number of valid columns (columns that do not contain "Reserved") in the Rel. 15 table is 14 (rank 1), and as shown in Figures 8A-8D, the maximum number of valid columns in the Rel. 18 table is 4 (rank 5), so these 8 bits are wasted.

[0177] 13B shows an example in which the antenna port field (A'+B') is represented by 5 bits, taking into consideration that the maximum number of columns to be represented is 14+4=18. The number of bits can be suitably reduced.

[0178] According to the second embodiment described above, the antenna port indication table can be dynamically switched based on the DCI.

[0179] Third Embodiment The third embodiment relates to a method for switching the antenna port indication table for PDSCH DMRS, a method for determining the DMRS port corresponding to the antenna port field, and the like.

[0180] In the first and second embodiments, the switching of the antenna port indication table for the PUSCH DMRS has been mainly described. The antenna port indication table for the PUSCH DMRS is defined for each rank. The UE receives the rank indication from the precoding information field (in the case of codebook-based transmission) or the SRI (in the case of non-codebook-based transmission), and determines the DMRS port based on the antenna port field by referring to the antenna port indication table corresponding to the rank. For the PUSCH DMRS, the number of DMRS ports is the same as the indicated rank.

[0181] On the other hand, for PDSCH DMRS, the number of DMRS ports is determined based on the antenna port field, and different code points in the antenna port field may correspond to different numbers of DMRS ports.

[0182] 14 is a diagram showing an example of a table of antenna ports to be referenced for PDSCH DMRS when the DMRS configuration type is 1 and the maximum DMRS length is 1 in Rel.

[0183] The Rel. 15 table in Figure 14 can only indicate a CDM group count of 2 or less for DMRS configuration type 1. Furthermore, the Rel. 15 table can indicate one to four of the DMRS ports with port numbers (port indexes) 0-3. The PDSCH DMRS port number actually corresponds to the value shown in the figure plus 1000 (the same applies to the subsequent drawings of the PDSCH DMRS antenna port indication table).

[0184] The UE may receive a DCI for the PDSCH including a value for the antenna port indication (antenna port field) and control the reception of the DMRS / PDSCH based on the association between the value and the number of CDM groups and the DMRS port (antenna port indication table).

[0185] For PDSCH DMRS, Rel. 15 DMRS ports may refer to ports whose port numbers correspond to at least one of the following: Port numbers 1000-1007 (for DMRS configuration type 1. The total number of DMRS ports is 2 (by comb / FDM) × (by FD OCC) 2 = 4 ports for single-symbol DMRS and 2 (by comb / FDM) × (by FD OCC) 2 × (by TD OCC) 2 = 8 ports for double-symbol DMRS), and Port numbers 1000-1011 (for DMRS configuration type 2. The total number of DMRS ports is 3 (by FDM) × (by FD OCC) 2 = 6 ports for single-symbol DMRS and 3 (by FDM) × (by FD OCC) 2 × (by TD OCC) 2 = 12 ports for double-symbol DMRS).

[0186] On the other hand, for PDSCH DMRS, a Rel. 18 DMRS port may refer to a port whose port number corresponds to at least one of the following: a port number greater than 1007 (e.g., port numbers 1008-1015) (for DMRS configuration type 1), and a port number greater than 1011 (e.g., port numbers 1012-1023) (for DMRS configuration type 2).

[0187] An antenna port indication table for PDSCH DMRS in the third embodiment will be described below, but before that, an example of Rel. 18 DMRS port numbers will be shown.

[0188] Figure 15 is a diagram showing an example of parameters for DMRS configuration type 1 for Rel. 18 DMRS. Figure 16 is a diagram showing an example of parameters for DMRS configuration type 2 for Rel. 18 DMRS. In Figures 15 and 16, entries (including at least one of CDM group, Δ, FD OCC, and TD OCC) corresponding to existing DMRS port indexes (1000-1007 for DMRS configuration type 1 and 1000-1011 for DMRS configuration type 2) may not be changed from the existing parameter correspondence (Figures 1 and 2).

[0189] That is, Fig. 15 is a table in which entries corresponding to Rel. 18 DMRS ports (port numbers 1008-1015) are added to the correspondence relationship for DMRS setting type 1 in Fig. 1. Also, Fig. 16 is a table in which entries corresponding to Rel. 18 DMRS ports (port numbers 1012-1023) are added to the correspondence relationship for DMRS setting type 2 in Fig. 1.

[0190] In this example, for single symbol DMRS, port numbers 1000-1003 and 1008-1011 may be used in FIG. 15, and port numbers 1000-1005 and 1012-1017 may be used in FIG.

[0191] In addition, new FD OCC (w ｆFor example, for DMRS configuration type 1, a length 6 FD OCC (k' = 0-5) may be used, and for DMRS configuration type 2, a length 4 FD OCC (k' = 0-3) may be used.

[0192] 15 and 16, the implementation of the UE / base station can be simplified. Note that the Rel. 18 DMRS port number is not limited to the examples in FIGS. 15 and 16.

[0193] Note that in this disclosure, a Rel. 18 table for PDSCH DMRS may refer to a table that is different from a table specified in Rel. 15 (Rel. 15 table) that can be used for a certain number of codewords, a certain DMRS configuration type, and a certain maximum DMRS length.

[0194] For example, the Rel. 18 table for PDSCH DMRS may refer only to the antenna port indication table for DMRS ports for rank 9 or higher (e.g., number of layers≦12, number of layers≦16) where the maximum number of DMRS ports is the same as in Rel. 15, or may refer only to the antenna port indication table for DMRS ports for any rank (e.g., number of layers≦4, number of layers≦8) where the maximum number of DMRS ports is n times (e.g., n=2, 3, 4, ...) that of the same DMRS configuration (e.g., DMRS configuration type, DMRS mapping type, single / double symbol DMRS) in Rel. 15, or may refer to both of these tables. n may be predetermined by the standard or configured in the UE by higher layer signaling.

[0195] In the present disclosure, the Rel. 15 / Rel. 18 DMRS port number for PUSCH DMRS may correspond to the Rel. 15 / Rel. 18 DMRS port number for PDSCH DMRS minus 1000. In other words, the content regarding the Rel. 15 / Rel. 18 DMRS port number for PDSCH DMRS may be interchangeably read as the content regarding the Rel. 15 / Rel. 18 DMRS port number for PUSCH DMRS minus 1000.

[0196] [Embodiment 3.1] In embodiment 3.1, the antenna port field of the DCI is used to dynamically switch between Rel. 15 DMRS and Rel. 18 DMRS. Different values ​​(different code points) of the antenna port field indicate either a Rel. 15 DMRS port or a Rel. 18 DMRS port.

[0197] FIG. 17 is a diagram illustrating an example of a table of antenna ports to be referenced for a PDSCH DMRS when the DMRS configuration type=1 and the maximum DMRS length=1 according to embodiment 3.1.

[0198] Note that the DMRS configuration (DMRS configuration type, maximum DMRS length, etc.) and PDSCH configuration (number of codewords, etc.) in this example are merely examples, and the contents of the present disclosure are not limited thereto. The same applies to the subsequent drawings.

[0199] In the antenna port indication table of Figure 17, values ​​0-11 are the same as those in the Rel. 15 table of Figure 14. However, in this example, for values ​​12-15, the corresponding entries of the Rel. 18 DMRS ports shown in the figure are referenced, rather than the "Reserved" column.

[0200] FIG. 18 is a diagram illustrating an example of a table of antenna ports to be referenced for a PDSCH DMRS when the DMRS configuration type=1 and the maximum DMRS length=1 according to embodiment 3.1.

[0201] The antenna port indication table on the left side of Figure 18 is a table used when the UE receives an activation command that maps at least one codepoint in the Transmission Configuration Indication (TCI) field included in the DCI to two TCI states. In other words, the antenna port indication table on the left side of Figure 18 is one of the antenna port indication tables used in Rel. 16.

[0202] In the antenna port indication table of Figure 18, values ​​0-12 are the same as those in the antenna port indication table used in Rel. 16. However, in this example, values ​​13-15 refer to the corresponding entries for the Rel. 18 DMRS ports shown in the figure, rather than the "Reserved" column.

[0203] Note that, in addition to the existing tables for Rel. 15 / 16, an antenna port instruction table for Rel. 18 DMRS ports as shown in Figures 17-18 (for example, a table for values ​​12-15 in Figure 17) may be defined. Also, in addition to the existing tables for Rel. 15 / 16, a table merging an existing table as shown in Figures 17-18 and an antenna port instruction table for Rel. 18 DMRS ports (for example, a table for values ​​0-15 in Figure 17) may be defined. Also, in order to replace the existing tables for Rel. 15 / 16, a table merging an existing table as shown in Figures 17-18 and an antenna port instruction table for Rel. 18 DMRS ports (for example, a table for values ​​0-15 in Figure 17) may be defined.

[0204] These new tables / values ​​may be assumed to be configured / indicated only to UEs that are configured / support Rel. 18 DMRS.

[0205] [Embodiment 3.2] Embodiment 3.2 is a modification of Embodiment 3.1. Similarities with Embodiment 3.1 will not be repeated. In Embodiment 3.2, the size of the antenna port field is extended by x bits (e.g., x = 1) compared to the case of the same DMRS configuration (DMRS configuration type, DMRS maximum length, etc.) / same PDSCH configuration (number of codewords, etc.) in Rel. 15 / 16. Embodiment 3.2 may be applied when the configuration related to this bit extension is configured in the UE by higher layer signaling.

[0206] 19 is a diagram illustrating an example of a table of antenna ports to be referenced for a PDSCH DMRS according to embodiment 3.2, when the DMRS configuration type is 1 and the maximum DMRS length is 1. In this example, it is assumed that the above x=1.

[0207] Figure 19 is similar to Figure 17, except that the antenna port field has been extended by one bit, resulting in possible values ​​of 0-31, and values ​​12-23 refer to the corresponding Rel. 18 DMRS port entry shown instead of the "Reserved" column.

[0208] FIG. 20 is a diagram illustrating an example of a table of antenna ports to be referenced for a PDSCH DMRS when the DMRS configuration type=1 and the maximum DMRS length=1 according to embodiment 3.2.

[0209] Figure 20 is similar to Figure 18, except that the antenna port field has been extended by one bit, resulting in possible values ​​of 0-31, and values ​​13-25 refer to the corresponding Rel. 18 DMRS port entry shown instead of the "Reserved" column.

[0210] 19-20, the correspondence relationship of the Rel. 18 DMRS port includes entries in which each value in the existing Rel. 15 / 16 table is incremented by +12 and each DMRS port index is incremented by +8, but this is not limited to this. For example, the UE may use a value set by higher layer signaling instead of this +8.

[0211] Note that, in addition to the existing tables for Rel. 15 / 16, an antenna port instruction table for Rel. 18 DMRS ports as shown in Figures 19-20 (for example, a table for values ​​12-31 in Figure 19) may be defined. Also, in addition to the existing tables for Rel. 15 / 16, a table merging the existing tables as shown in Figures 19-20 and the antenna port instruction table for Rel. 18 DMRS ports (for example, a table for values ​​0-31 in Figure 19) may be defined.

[0212] These new tables / values ​​may be assumed to be configured / indicated only to UEs that are configured / support Rel. 18 DMRS.

[0213] [Embodiment 3.3] Embodiment 3.3 is a modification of Embodiments 3.1 / 3.2. Similar points to Embodiments 3.1 / 3.2 will not be described repeatedly. In Embodiment 3.3, when the use of a new antenna port indication table is configured by higher layer signaling (e.g., RRC signaling, MAC CE), the UE refers to the antenna port indication table (hereinafter also simply referred to as a dynamic switching table) that can dynamically switch between Rel. 15 DMRS and Rel. 18 DMRS shown in Embodiments 3.1 / 3.2.

[0214] FIG. 21 is a diagram illustrating an example of a table of antenna ports to be referenced for a PDSCH DMRS when the DMRS configuration type=1 and the maximum DMRS length=1 according to embodiment 3.3.

[0215] In this example, the UE may switch between the Rel. 15 table (left) and the dynamic switching table (right) based on higher layer signaling.

[0216] In the table on the right, values ​​0-4 correspond to Rel. 15 DMRS (e.g., one or more combinations of port numbers 0-3), and values ​​5-15 correspond to Rel. 18 DMRS (e.g., one or more combinations of port numbers 8-11).

[0217] Note that a dynamic switching table (for example, the right side of FIG. 21) may be defined separately from the existing table of Rel. 15 / 16 (for example, the left side of FIG. 21).

[0218] These new tables / values ​​may be assumed to be configured / indicated only to UEs that are configured / support Rel. 18 DMRS.

[0219] The code points (or the contents of the entries) in the dynamic switching table may be updated by higher layer signaling. In this case, the base station can flexibly update the association between the code points in the antenna port field and the DMRS ports. Note that if the size of the antenna port field is not increased from the existing size, it is not possible to indicate all DMRS ports in Rel. 15 and 18, so the above-mentioned update is preferable. Note that which DMRS ports are likely to be used is up to the base station (considered to depend on each UE that configures it).

[0220] FIG. 22 is a diagram illustrating an example of a table of antenna ports to be referenced for a PDSCH DMRS when the DMRS configuration type=1 and the maximum DMRS length=1 according to embodiment 3.3.

[0221] Both tables shown are dynamic switching tables, but the left one has more rows for Rel. 15 DMRS ports, and the right one has more rows for Rel. 18 DMRS ports. By configuring the UE to use the table on the left, the base station can specify Rel. 15 DMRS with greater flexibility (e.g., finer granularity). Also, by configuring the UE to use the table on the right, the base station can specify Rel. 18 DMRS with greater flexibility (e.g., finer granularity).

[0222] The update may be achieved based on at least one of the following: - defining / configuring multiple antenna port indication tables and specifying one of these tables to the UE via higher layer signaling; - specifying the number of DMRS ports / CDM groups corresponding to the codepoint in the antenna port field to the UE via higher layer signaling.

[0223] The latter will be described in more detail below. In the following description, "DMRS port" may be read interchangeably with "number of DMRS ports / CDM groups."

[0224] [DMRS Port Designation Method 1] Higher layer signaling may explicitly designate one or more DMRS port indices corresponding to code points (similar to designating the index of "DMRS port(s)" corresponding to the code point (value) in Figures 21 and 22, etc.). In this case, high flexibility can be achieved in the configuration of the table.

[0225] DMRS Port Designation Method 2: Higher layer signaling may designate a combination of one or more DMRS port indices corresponding to a code point. Compared to the above-described designation method 1, this method can reduce communication overhead required for DMRS port designation.

[0226] The above combinations (set / list) may be defined in advance in a standard, or may be configured in the UE by separate higher layer signaling.

[0227] Hereinafter, as an example, combinations of values ​​and DMRS port indices included in the antenna port indication table in Fig. 19 are used. In this case, the set of combinations is values ​​0-23 (24 in total) in Fig. 19.

[0228] If the size of the antenna port field is 4 bits, the values ​​of the antenna port indication table corresponding to each of the 16 code points may be specified from the above 24 values ​​by higher layer signaling. ２４ C １６ It may be a bit number (20 bits) that can indicate the combinations of the above, or a bitmap (24 bits) that indicates whether each of the 24 combinations is included in the code point.

[0229] In addition, if the number of combinations (values) specified by higher layer signaling is less than the total number of code points (here, 16), the UE may associate the combinations in ascending order starting from the value 0 of the antenna port field, and may assume that the value of the antenna port field with no corresponding combination indicates "Reserved".

[0230] All of the code points may or may not be capable of being specified as combinations by higher layer signaling. For example, among the 16 code points, combinations corresponding to K code points (e.g., K=4) may be fixedly determined, and in that case, higher layer signaling may be used to specify combinations for the 16-K code points.

[0231] 23A and 23B are diagrams illustrating an example of the correspondence between the value of the antenna port field and the corresponding DMRS port for the DMRS port designation method 2 according to the third embodiment.

[0232] Figure 23A is the same table as the antenna port instruction table in Figure 19. In this example, it is assumed that, as in Figure 23B, the association between each of the 4-bit code points and the values ​​in the antenna port instruction table in Figure 23A is configured for the UE using higher layer signaling. Note that this example shows an example in which the corresponding value monotonically increases according to the value of the code point in the antenna port field (i.e., the combination corresponding to code point i (i is an integer) is smaller than the combination corresponding to code point i+1), but the example is not limited to this.

[0233] For example, if the UE determines that the value of the antenna port field included in the DCI is 8, it processes the DMRS based on the DMRS port number 8 corresponding to the associated value 12 based on FIG. 23A.

[0234] DMRS Port Designation Method 3: Higher layer signaling may specify start and end indices for Rel. 15 / 18 DMRS ports that can be specified by the antenna port field among the values ​​(indexes) included in the antenna port designation table. This higher layer signaling may indicate the start and end indices, or may indicate the start index and the difference (length) between the start and end indices. Compared to the above-mentioned designation methods 1 and 2, this method can further reduce the communication overhead required for DMRS port designation.

[0235] Note that the UE may associate the antenna port field value from 0 in ascending order, from the start index to the end index of the Rel. 15 (or 18) DMRS, and then from the start index to the end index of the Rel. 18 (or 15) DMRS, and may assume that the value of the antenna port field for which there is no corresponding combination indicates "Reserved."

[0236] Note that the ending index for Rel. 15 / 18 DMRS ports may not be specified. For example, if the ending index for Rel. 15 DMRS ports is not specified, the UE may assume that the ending index for Rel. 15 DMRS ports is the largest index for Rel. 15 DMRS ports included in the antenna port indication table. Also, if the ending index for Rel. 18 DMRS ports is not specified, the UE may assume that the ending index for Rel. 18 DMRS ports is the largest index for Rel. 18 DMRS ports included in the antenna port indication table.

[0237] Also, the starting index for Rel. 15 / 18 DMRS ports may not be specified. For example, if the starting index for Rel. 15 DMRS ports is not specified, the UE may assume that the starting index for the Rel. 15 DMRS ports is the smallest index for the Rel. 15 DMRS ports included in the antenna port indication table. Also, if the starting index for the Rel. 18 DMRS ports is not specified, the UE may assume that the starting index for the Rel. 18 DMRS ports is the smallest index for the Rel. 18 DMRS ports included in the antenna port indication table.

[0238] 24A and 24B are diagrams illustrating an example of the correspondence between the value of the antenna port field and the corresponding DMRS port for the DMRS port designation method 3 according to the third embodiment.

[0239] Figure 24A is the same table as the antenna port indication table in Figure 19. In this example, it is assumed that 1 and 9 are specified as the start index and end index for Rel. 15 DMRS, respectively, and 15 and 21 are specified as the start index and end index for Rel. 18 DMRS, respectively (note that even if 21 is not specified, the result in this example will be the same).

[0240] Based on the start / end indexes in FIG. 24A, the UE determines the association between each of the 4-bit code points shown in FIG. 24B and a value in the antenna port indication table in FIG. 24A.

[0241] [DMRS Port Designation Method 4] A border index (which may also be referred to as a border value, border, etc.) may be configured in the UE via higher layer signaling instead of a start / end index. The UE may map the smallest (or largest) to the border-th index associated with Rel. 15 DMRS ports to code points in the antenna port field. Alternatively, the UE may not map the smallest (or largest) to the border-th index associated with Rel. 18 DMRS ports to code points in the antenna port field, but may map the border+1 index and subsequent indices (before border-1 index) to code points in the antenna port field.

[0242] 25A and 25B are diagrams illustrating an example of a correspondence relationship between the value of the antenna port field and the corresponding DMRS port for DMRS port designation method 4 according to the third embodiment.

[0243] Figure 25A is the same table as the antenna port indication table in Figure 19. In this example, it is assumed that 7 is specified as the border (for Rel. 15 DMRS).

[0244] Based on the border of Figure 25A, the UE determines the association between each of the 4-bit code points shown in Figure 25B and values ​​in the antenna port indication table of Figure 25A. Specifically, the UE maps the seven smallest indexes (i.e., values ​​0-6) among the indexes (values ​​0-11) associated with Rel. 15 DMRS ports to code points 0-6, for example. Furthermore, the UE maps the eighth smallest indexes (values ​​19-23) among the indexes (values ​​12-23) associated with Rel. 18 DMRS ports to code points 7-11, for example. The remaining code points 12-15 may be mapped to "Reserved."

[0245] In Figure 25B, as shown in Figure 25A, among the indexes (values ​​0-11) associated with Rel. 15 DMRS ports, the indexes (values ​​7-11) from the border + 1 (= 8) onwards are not used. Also, among the indexes (values ​​12-23) associated with Rel. 18 DMRS ports, the indexes (values ​​12-18) up to the border (= 7) are not used.

[0246] Note that the border may have a value greater than or equal to 0 and less than or equal to {the number of indices associated with the Rel. 15 (or Rel. 18) DMRS port minus 1}. In the case of Figure 25A, the border may have a value greater than or equal to 0 and less than or equal to 11, and can be specified by 4 bits.

[0247] Although specification method 4 is less flexible than the other specification methods, it is expected to significantly reduce the communication overhead involved in port specification.

[0248] According to the third embodiment described above, for PDSCH DMRS, the Rel. 15 / 18 DMRS port can be appropriately determined based on the antenna port field.

[0249] <Fourth Embodiment> The fourth embodiment relates to a method for switching the antenna port indication table for PUSCH DMRS, a method for determining the DMRS port corresponding to the antenna port field, and the like.

[0250] The fourth embodiment may correspond to an embodiment in which the PDSCH (PDSCH DMRS) of the third embodiment is replaced with PUSCH (PUSCH DMRS). The contents corresponding to the PDSCH (PDSCH DMRS) (such as the contents of the antenna port indication table) may be replaced with the contents corresponding to the PUSCH (PUSCH DMRS). The fourth embodiment in which embodiments 3.1-3.3 are replaced may be referred to as embodiments 4.1-4.3, respectively.

[0251] FIG. 26 is a diagram illustrating an example of a table of antenna ports to be referred to for a PUSCH DMRS when the DMRS configuration type is 1, the maximum DMRS length is 1, and the rank is 1 according to embodiment 4.1.

[0252] In the antenna port indication table of Figure 26, values ​​0-5 are the same as in the existing Rel. 15 table. However, in this example, for values ​​6-7, the corresponding entries of the Rel. 18 DMRS ports shown in the figure are referenced, rather than the "Reserved" column.

[0253] FIG. 27 is a diagram illustrating an example of a table of antenna ports to be referred to for a PUSCH DMRS when the DMRS configuration type is 1, the maximum DMRS length is 1, and the rank is 2 according to embodiment 4.1.

[0254] In the antenna port indication table of Figure 27, values ​​0-3 are the same as in the existing Rel. 15 table. However, in this example, values ​​4-7 refer to the corresponding entries of the Rel. 18 DMRS ports shown in the figure, rather than the "Reserved" column.

[0255] FIG. 28 is a diagram illustrating an example of a table of antenna ports to be referred to for a PUSCH DMRS when the DMRS configuration type is 1, the maximum DMRS length is 1, and the rank is 3 according to embodiment 4.1.

[0256] In the antenna port indication table of Figure 28, the value 0 is the same as the existing Rel. 15 table. However, in this example, for the value 1, the Rel. 18 DMRS port correspondence entry shown in the figure is referenced instead of the "Reserved" column.

[0257] FIG. 29 is a diagram illustrating an example of a table of antenna ports to be referred to for a PUSCH DMRS when the DMRS configuration type is 1, the maximum DMRS length is 1, and the rank is 4 according to embodiment 4.1.

[0258] In the antenna port indication table of Figure 29, the value 0 is the same as the existing Rel. 15 table. However, in this example, for the value 1, the corresponding entry of the Rel. 18 DMRS port shown in the figure is referenced instead of the "Reserved" column.

[0259] According to the fourth embodiment described above, for the PUSCH DMRS, the Rel. 15 / 18 DMRS port can be appropriately determined based on the antenna port field.

[0260] Fifth Embodiment The fifth embodiment relates to switching of antenna port indication tables for PDSCH DMRS.

[0261] The fifth embodiment may correspond to an embodiment in which the PUSCH (PUSCH DMRS) in the first and second embodiments is replaced with the PDSCH (PDSCH DMRS), and the contents corresponding to the PUSCH (PUSCH DMRS) (such as the contents of the antenna port indication table) are replaced with the contents corresponding to the PDSCH (PDSCH DMRS).

[0262] For DMRS configuration type 1, the UE may determine based on the DCI whether the DMRS port referenced by the antenna port field is a Rel. 15 DMRS port (port numbers 1000-1007) or a Rel. 18 DMRS port (port numbers 1008-1015).

[0263] For DMRS configuration type 2, the UE may determine based on the DCI whether the DMRS port referenced by the antenna port field is a Rel. 15 DMRS port (port numbers 1000-1011) or a Rel. 18 DMRS port (port numbers 1012-1023).

[0264] 30 is a diagram illustrating an example of switching of the antenna port instruction table based on DCI according to the fifth embodiment. In this example, the Rel. 15 table (left side) or the Rel. 18 table (right side) is switched by DCI.

[0265] <Supplementary Note> In the present disclosure, when a UE / base station uses (referring to / performing processing based on) a table, it does not necessarily mean using the table itself, but may also mean using an array, list, function, etc. that includes information that conforms to the table.

[0266] [Port Group Subset] In the above-described embodiment, Rel. 15 DMRS ports and Rel. 18 DMRS ports are distinguished (identified) by port numbers, but this is not limiting. Rel. 15 DMRS ports and Rel. 18 DMRS ports may be defined as using the same port number but belonging to different port group subsets.

[0267] For example, for DMRS configuration type 1, existing Rel. 15 DMRS ports may be represented as ports with port numbers 1000-1007 in subset #0, and Rel. 18 DMRS ports may be represented as ports with port numbers 1000-1007 in subset #1.

[0268] In addition, for DMRS configuration type 2, existing Rel. 15 DMRS ports may be expressed as ports with port numbers 1000-1011 in subset #0, and Rel. 18 DMRS ports may be expressed as ports with port numbers 1000-1011 in subset #1.

[0269] When utilizing the concept of port group subsets, it is not necessary to use new parameter correspondences, new antenna port indication tables, etc., and existing parameter correspondences (Figures 1 and 2), existing antenna port indication tables, etc. may be used.

[0270] [Notification of Information to UE] In the above-described embodiments, any information may be notified to the UE (from a network (NW) (e.g., a base station (BS))) (in other words, reception of any information from the BS by the UE) using physical layer signaling (e.g., DCI), higher layer signaling (e.g., RRC signaling, MAC CE), a specific signal / channel (e.g., PDCCH, PDSCH, reference signal), or a combination thereof.

[0271] When the notification is performed by a MAC CE, the MAC CE may be identified by including a new Logical Channel ID (LCID) in the MAC subheader, which is not defined in existing standards.

[0272] When the notification is made by DCI, the notification may be made by a specific field of the DCI, a Radio Network Temporary Identifier (RNTI) used to scramble Cyclic Redundancy Check (CRC) bits assigned to the DCI, the format of the DCI, etc.

[0273] Furthermore, notification of any information to the UE in the above embodiments may be performed periodically, semi-persistently, or aperiodically.

[0274] [Notification of Information from UE] In the above-described embodiments, notification of any information from the UE (to the NW) (in other words, transmission / report of any information from the UE to the BS) may be performed using physical layer signaling (e.g., UCI), higher layer signaling (e.g., RRC signaling, MAC CE), a specific signal / channel (e.g., PUCCH, PUSCH, PRACH, reference signal), or a combination thereof.

[0275] When the notification is performed by a MAC CE, the MAC CE may be identified by including a new LCID, which is not defined in existing standards, in the MAC subheader.

[0276] If the notification is made by UCI, the notification may be transmitted using PUCCH or PUSCH.

[0277] Furthermore, any information in the above-described embodiments may be notified from the UE periodically, semi-persistently, or aperiodically.

[0278] [Application of Each Embodiment] At least one of the above-described embodiments may be applied when a specific condition is met. The specific condition may be defined in a standard or may be notified to a UE / BS using higher layer signaling / physical layer signaling.

[0279] At least one of the above-described embodiments may be applied only to UEs that have reported or support a particular UE capability.

[0280] The specific UE capabilities may indicate at least one of the following: Supporting specific processing / operations / control / information for at least one of the above embodiments, Supporting dynamic switching of Rel. 15 DMRS ports (tables) and Rel. 18 DMRS ports (tables).

[0281] Furthermore, the above-mentioned specific UE capability may be a capability that is applied across all frequencies (commonly regardless of frequency), or may be a capability for each frequency (e.g., one or a combination of a cell, a band, a band combination, a BWP, a component carrier, etc.), or may be a capability for each frequency range (e.g., Frequency Range 1 (FR1), FR2, FR3, FR4, FR5, FR2-1, FR2-2), or may be a capability for each subcarrier spacing (SubCarrier Spacing (SCS)), or may be a capability for each Feature Set (FS) or Feature Set Per Component-carrier (FSPC).

[0282] Furthermore, the specific UE capability may be a capability that is applied to all duplexing methods (commonly regardless of the duplexing method), or may be a capability for each duplexing method (e.g., Time Division Duplex (TDD) or Frequency Division Duplex (FDD)).

[0283] Furthermore, at least one of the above-described embodiments may be applied when a UE configures / activates / triggers specific information related to the above-described embodiments (or performs the operations of the above-described embodiments) through higher layer signaling / physical layer signaling. For example, the specific information may be information indicating enabling dynamic switching of DMRS ports, information indicating enabling dynamic switching of DMRS ports of a specific release (e.g., Rel. 15 DMRS ports and Rel. 18 DMRS ports), information indicating enabling dynamic switching of antenna port indication tables, any RRC parameters for a specific release (e.g., Rel. 18 / 19), etc.

[0284] If the UE does not support at least one of the specific UE capabilities or is not configured with the specific information, the UE may apply, for example, Rel. 15 / 16 behavior.

[0285] (Supplementary Notes) The following inventions are supplementary notes regarding one embodiment of the present disclosure. [Supplementary Note 1] A terminal comprising: a receiver that receives Downlink Control Information (DCI) for scheduling an uplink shared channel; and a controller that selects, from a plurality of tables for a certain rank, an antenna port indication table related to Demodulation Reference Signal (DMRS) port indication for the uplink shared channel, based on a specific field of the DCI. [Supplementary Note 2] The terminal according to Supplementary Note 1, wherein the specific field is a field that explicitly indicates the antenna port indication table.

[0286] (Supplementary Notes) The following inventions are supplementary notes regarding one embodiment of the present disclosure. [Supplementary Note 1] A terminal comprising: a receiver that receives Downlink Control Information (DCI) for scheduling a Downlink Shared Channel; and a controller that refers to an antenna port instruction table regarding DMRS port instructions for the Downlink Shared Channel, the table including, for Demodulation Reference Signal (DMRS) configuration type 1, a column including port numbers 1007 or less and a column including port numbers 1008 or more, or for DMRS configuration type 2, a column including port numbers 1011 or less and a column including port numbers 1012 or more. [Supplementary Note 2] The terminal according to Supplementary Note 1, wherein the controller determines a correspondence relationship between DMRS ports corresponding to code points in the antenna port field based on higher layer signaling.

[0287] (Wireless Communication System) The configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof.

[0288] 31 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 (which may be simply referred to as system 1) may be a system that realizes communication using Long Term Evolution (LTE) or 5th generation mobile communication system New Radio (5G NR) specified by the Third Generation Partnership Project (3GPP).

[0289] The wireless communication system 1 may also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

[0290] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (Master Node (MN)), and the NR base station (gNB) is the secondary node (Secondary Node (SN)). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0291] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity in which both the MN and SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0292] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with a relatively wide coverage, and base stations 12 (12a-12c) that are located within the macrocell C1 and form small cells C2 that are smaller than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The locations and numbers of the cells and user terminals 20 are not limited to the embodiment shown in the figure. Hereinafter, when there is no need to distinguish between the base stations 11 and 12, they will be collectively referred to as base station 10.

[0293] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CCs) and dual connectivity (DC).

[0294] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band higher than 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may correspond to a higher frequency band than FR2.

[0295] Furthermore, the user terminal 20 may perform communication using at least one of time division duplex (TDD) and frequency division duplex (FDD) in each CC.

[0296] The multiple base stations 10 may be connected by wire (e.g., optical fiber compliant with the Common Public Radio Interface (CPRI), an X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication is used as a backhaul between the base stations 11 and 12, the base station 11 corresponding to the upper station may be called an Integrated Access Backhaul (IAB) donor, and the base station 12 corresponding to the relay station (relay) may be called an IAB node.

[0297] The base station 10 may be connected to the core network 30 directly or via another base station 10. The core network 30 may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

[0298] The core network 30 may include network functions (Network Functions (NF)) such as a User Plane Function (UPF), an Access and Mobility management Function (AMF), a Session Management Function (SMF), a Unified Data Management (UDM), an Application Function (AF), a Data Network (DN), a Location Management Function (LMF), and Operation, Administration and Maintenance (Management) (OAM). A single network node may provide multiple functions. Communication with an external network (e.g., the Internet) may also be performed via the DN.

[0299] The user terminal 20 may be a terminal that supports at least one of communication methods such as LTE, LTE-A, and 5G.

[0300] An Orthogonal Frequency Division Multiplexing (OFDM)-based radio access scheme may be used in the wireless communication system 1. For example, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used in at least one of the downlink (DL) and uplink (UL).

[0301] The radio access scheme may also be called a waveform. Note that in the wireless communication system 1, other radio access schemes (e.g., other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0302] In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as the downlink channel.

[0303] Furthermore, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), or the like may be used as an uplink channel.

[0304] The PDSCH transmits user data, higher layer control information, a System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit a Master Information Block (MIB).

[0305] Lower layer control information may be transmitted by the PDCCH. The lower layer control information may include, for example, Downlink Control Information (DCI) including scheduling information for at least one of the PDSCH and the PUSCH.

[0306] Note that the DCI for scheduling the PDSCH may be referred to as a DL assignment, a DL DCI, etc., and the DCI for scheduling the PUSCH may be referred to as a UL grant, a UL DCI, etc. Note that the PDSCH may be replaced with DL data, and the PUSCH may be replaced with UL data.

[0307] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources for searching for DCI. The search space corresponds to a search region and a search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor the CORESET associated with a certain search space based on the search space configuration.

[0308] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be referred to as a search space set. Note that the terms "search space," "search space set," "search space configuration," "search space set configuration," "CORESET," "CORESET configuration," and the like in the present disclosure may be read interchangeably.

[0309] The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), delivery confirmation information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

[0310] In the present disclosure, downlink, uplink, etc. may be expressed without adding "link." Also, various channels may be expressed without adding "Physical" to the beginning.

[0311] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, as the DL-RS, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted.

[0312] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including an SS (PSS, SSS) and a PBCH (and a DMRS for the PBCH) may be referred to as an SS / PBCH block, an SS Block (SSB), or the like. Note that the SS, SSB, and the like may also be referred to as a reference signal.

[0313] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), or the like may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may also be called a user equipment-specific reference signal (UE-specific reference signal).

[0314] 32 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that the base station may include one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140.

[0315] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the base station 10 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0316] The control unit 110 performs overall control of the base station 10. The control unit 110 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0317] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 120. The control unit 110 may perform call processing (setting up, releasing, etc.) of communication channels, status management of the base station 10, management of radio resources, etc.

[0318] The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0319] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or may be configured from a transmitting unit and a receiving unit. The transmitting unit may be configured from a transmission processing unit 1211 and an RF unit 122. The receiving unit may be configured from a reception processing unit 1212, the RF unit 122, and a measurement unit 123.

[0320] The transmitting and receiving antenna 130 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

[0321] The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

[0322] The transceiver 120 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0323] The transmitter / receiver unit 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0324] The transmitter / receiver unit 120 (transmission processing unit 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0325] The transceiver unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 130.

[0326] On the other hand, the transceiver unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 130.

[0327] The transceiver 120 (reception processing unit 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, thereby acquiring user data, etc.

[0328] The transceiver 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

[0329] The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30 (e.g., network nodes that provide NF), other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0330] The transmitting section and receiving section of the base station 10 in the present disclosure may be configured by at least one of the transmitting / receiving section 120, the transmitting / receiving antenna 130, and the transmission path interface 140.

[0331] The transceiver 120 may transmit Downlink Control Information (DCI) for scheduling the uplink shared channel to the user terminal 20. The control unit 110 may determine the DMRS port for the uplink shared channel based on an antenna port instruction table related to demodulation reference signal (DMRS) port instructions for the uplink shared channel, which is selected from a plurality of tables for a certain rank based on a specific field of the DCI.

[0332] Furthermore, the transceiver unit 120 may transmit downlink control information (DCI) for scheduling a downlink shared channel to the user terminal 20. The control unit 110 may determine a DMRS port for the downlink shared channel corresponding to the antenna port field of the DCI based on an antenna port indication table related to DMRS port indication for the downlink shared channel, the table including, for Demodulation Reference Signal (DMRS) configuration type 1, a column including port numbers equal to or less than 1007 and a column including port numbers equal to or greater than 1008, or for DMRS configuration type 2, a column including port numbers equal to or less than 1011 and a column including port numbers equal to or greater than 1012.

[0333] (User terminal) Fig. 33 is a diagram showing an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transceiver antenna 230. Note that the user terminal 20 may include one or more of each of the control unit 210, the transceiver unit 220, and the transceiver antenna 230.

[0334] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0335] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured from a controller, a control circuit, etc., which are described based on common understanding in the technical field to which the present disclosure relates.

[0336] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may control transmission and reception, measurement, etc. using the transceiver unit 220 and the transceiver antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals and transfer them to the transceiver unit 220.

[0337] The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0338] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 2211 and an RF unit 222. The receiving unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

[0339] The transmitting / receiving antenna 230 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

[0340] The transceiver 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0341] The transceiver unit 220 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0342] The transceiver unit 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

[0343] The transmitter / receiver unit 220 (transmission processing unit 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0344] Whether or not to apply DFT processing may be based on the setting of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the transmission processing to transmit the channel using a DFT-s-OFDM waveform, and if not, it may not be necessary to perform DFT processing as the transmission processing.

[0345] The transceiver unit 220 (RF unit 222) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 230.

[0346] On the other hand, the transceiver unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 230.

[0347] The transceiver unit 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data, etc.

[0348] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0349] The transmitting unit and receiving unit of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting / receiving unit 220 and the transmitting / receiving antenna 230.

[0350] The transceiver 220 may receive Downlink Control Information (DCI) for scheduling an uplink shared channel. The controller 210 may select an antenna port indication table for demodulation reference signal (DMRS) port indication for the uplink shared channel from a plurality of tables for a certain rank, based on a specific field of the DCI.

[0351] The specific field may be a field that explicitly indicates the antenna port indication table.

[0352] Furthermore, the transceiver 220 may receive Downlink Control Information (DCI) for scheduling a Downlink Shared Channel. The control unit 210 may refer to an antenna port indication table regarding DMRS port indication for the Downlink Shared Channel, the table including a column including port numbers equal to or less than 1007 and a column including port numbers equal to or greater than 1008 for a Demodulation Reference Signal (DMRS) configuration type 1, or a column including port numbers equal to or less than 1011 and a column including port numbers equal to or greater than 1012 for a DMRS configuration type 2, and determine a DMRS port for the Downlink Shared Channel based on an antenna port field of the DCI.

[0353] The control unit 210 may determine the correspondence between the code points in the antenna port field and the DMRS ports based on higher layer signaling.

[0354] (Hardware Configuration) Note that the block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may be realized by combining software with the single device or the multiple devices.

[0355] Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission may be called a transmitting unit, transmitter, etc. As described above, the implementation method of each is not particularly limited.

[0356] For example, a base station, a user terminal, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Figure 34 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. The above-described base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0357] In the present disclosure, the terms apparatus, circuit, device, section, unit, etc. may be used interchangeably. The hardware configurations of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0358] For example, although only one processor 1001 is shown, there may be multiple processors. Furthermore, processing may be performed by one processor, or processing may be performed by two or more processors simultaneously, serially, or in other ways. Furthermore, processor 1001 may be implemented by one or more chips.

[0359] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading specified software (programs) onto hardware such as a processor 1001 and a memory 1002, causing the processor 1001 to perform calculations, control communication via the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0360] The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), transceiver unit 120 (220), etc. may be realized by the processor 1001.

[0361] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002 and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 110 (210) may be implemented by a control program stored in the memory 1002 and running on the processor 1001, and the other functional blocks may be implemented in a similar manner.

[0362] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EEPROM (EEPROM), Random Access Memory (RAM), or other suitable storage medium. The memory 1002 may also be referred to as a register, cache, main memory, etc. The memory 1002 may store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to an embodiment of the present disclosure.

[0363] Storage 1003 is a computer-readable recording medium and may be composed of at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disc (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disc, a Blu-ray disc), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, a stick, a key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as an auxiliary storage device.

[0364] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmission / reception unit 120 (220), transmission / reception antenna 130 (230), etc. may be realized by the communication device 1004. The transmission / reception unit 120 (220) may be implemented as a transmission unit 120a (220a) and a reception unit 120b (220b) that are physically or logically separated.

[0365] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, a light emitting diode (LED) lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0366] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0367] Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using this hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0368] (Modifications) Note that terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applicable standard. A component carrier (CC) may also be called a cell, frequency carrier, carrier frequency, etc.

[0369] A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0370] Here, the numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, and may indicate at least one of, for example, Subcarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), number of symbols per TTI, radio frame structure, specific filtering performed by a transceiver in the frequency domain, and specific windowing performed by a transceiver in the time domain.

[0371] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol) in the time domain. A slot may also be a time unit based on numerology.

[0372] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

[0373] A radio frame, a subframe, a slot, a minislot, and a symbol all represent time units for transmitting signals. The radio frame, the subframe, the slot, the minislot, and the symbol may be referred to by other names corresponding to the radio frame, the subframe, the slot, the minislot, and the symbol. Note that the time units such as a frame, a subframe, a slot, a minislot, and a symbol in the present disclosure may be interchangeable.

[0374] For example, one subframe may be referred to as a TTI, or multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc. instead of a subframe.

[0375] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

[0376] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0377] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0378] A TTI having a time length of 1 ms may be called a regular TTI (TTI in 3GPP Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0379] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and greater than or equal to 1 ms.

[0380] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may be determined based on numerology.

[0381] In addition, an RB may include one or more symbols in the time domain and may have a length of one slot, one minislot, one subframe, or one TTI, each of which may be composed of one or more resource blocks.

[0382] In addition, one or more RBs may be referred to as a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0383] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0384] A Bandwidth Part (BWP), which may also be referred to as a partial bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0385] The BWP may include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0386] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0387] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0388] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by a predetermined index.

[0389] The names used for parameters and the like in this disclosure are not intended to be limiting in any way. Furthermore, the mathematical expressions and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0390] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0391] Furthermore, information, signals, etc. may be output from a higher layer to a lower layer and / or from a lower layer to a higher layer. Information, signals, etc. may be input / output via multiple network nodes.

[0392] Input and output information, signals, etc. may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0393] The notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information in the present disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0394] Note that the physical layer signaling may be referred to as Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Furthermore, the RRC signaling may be referred to as an RRC message, such as an RRC Connection Setup message or an RRC Connection Reconfiguration message. Furthermore, the MAC signaling may be notified using, for example, a MAC Control Element (CE).

[0395] Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may be made implicitly (e.g., by not notifying the specified information or by notifying other information).

[0396] The determination may be made by a value represented by one bit (0 or 1), by a Boolean value represented by true or false, or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0397] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0398] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), these wired and / or wireless technologies are included within the definition of transmission media.

[0399] As used in this disclosure, the terms "system" and "network" may be used interchangeably. A "network" may refer to devices included in the network (e.g., base stations).

[0400] In the present disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," etc. may be used interchangeably.

[0401] In the present disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "access point," "transmission point (TP)," "reception point (RP)," "transmission / reception point (TRP)," "panel," "cell," "sector," "cell group," "carrier," "component carrier," etc. may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, picocell, etc.

[0402] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be partitioned into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication service within that coverage.

[0403] In the present disclosure, a base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control / operate based on the information.

[0404] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0405] A mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0406] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a wireless communication device, etc. Note that at least one of the base station and the mobile station may be a device mounted on a moving object, the moving object itself, etc.

[0407] The mobile body is a movable object that can move at any speed and naturally includes cases where the mobile body is stationary. Examples of the mobile body include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones, multicopters, quadcopters, balloons, and objects mounted thereon. The mobile body may also be a mobile body that moves autonomously based on an operation command.

[0408] The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Note that at least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0409] 35 is a diagram showing an example of a vehicle according to an embodiment. The vehicle 40 includes a drive unit 41, a steering unit 42, an accelerator pedal 43, a brake pedal 44, a shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, an electronic control unit 49, various sensors (including a current sensor 50, an RPM sensor 51, an air pressure sensor 52, a vehicle speed sensor 53, an acceleration sensor 54, an accelerator pedal sensor 55, a brake pedal sensor 56, a shift lever sensor 57, and an object detection sensor 58), an information service unit 59, and a communication module 60.

[0410] The drive unit 41 is configured with at least one of an engine, a motor, and a hybrid of an engine and a motor, for example. The steering unit 42 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels 46 and the rear wheels 47 based on the operation of the steering wheel operated by a user.

[0411] The electronic control unit 49 is composed of a microprocessor 61, memory (ROM, RAM) 62, and a communication port (for example, an input / output (IO) port) 63. Signals are input to the electronic control unit 49 from various sensors 50-58 provided in the vehicle. The electronic control unit 49 may also be called an Electronic Control Unit (ECU).

[0412] The signals from the various sensors 50-58 include a current signal from a current sensor 50 that senses the current of the motor, a rotation speed signal of the front wheels 46 / rear wheels 47 obtained by a rotation speed sensor 51, an air pressure signal of the front wheels 46 / rear wheels 47 obtained by an air pressure sensor 52, a vehicle speed signal obtained by a vehicle speed sensor 53, an acceleration signal obtained by an acceleration sensor 54, a depression amount signal of the accelerator pedal 43 obtained by an accelerator pedal sensor 55, a depression amount signal of the brake pedal 44 obtained by a brake pedal sensor 56, an operation signal of the shift lever 45 obtained by a shift lever sensor 57, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 58.

[0413] The information service unit 59 is composed of various devices, such as a car navigation system, an audio system, speakers, a display, a television, and a radio, for providing (outputting) various information such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 59 uses information acquired from external devices via the communication module 60 or the like to provide various information / services (e.g., multimedia information / multimedia services) to the occupants of the vehicle 40.

[0414] The information service unit 59 may include input devices (e.g., keyboards, mice, microphones, switches, buttons, sensors, touch panels, etc.) that accept input from the outside, and may also include output devices (e.g., displays, speakers, LED lamps, touch panels, etc.) that output to the outside.

[0415] The driving assistance system unit 64 includes various devices for providing functions to prevent accidents and reduce the driver's driving burden, such as millimeter-wave radar, Light Detection and Ranging (LiDAR), cameras, positioning locators (e.g., Global Navigation Satellite System (GNSS)), map information (e.g., High Definition (HD) maps, Autonomous Vehicle (AV) maps), gyro systems (e.g., Inertial Measurement Units (IMUs), Inertial Navigation Systems (INSs)), artificial intelligence (AI) chips, and AI processors, as well as one or more ECUs that control these devices. The driving assistance system unit 64 also transmits and receives various information via the communication module 60 to realize driving assistance functions or autonomous driving functions.

[0416] The communication module 60 can communicate with the microprocessor 61 and components of the vehicle 40 via the communication port 63. For example, the communication module 60 transmits and receives data (information) via the communication port 63 to and from the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, the microprocessor 61 and memory (ROM, RAM) 62 in the electronic control unit 49, and the various sensors 50-58, which are provided in the vehicle 40.

[0417] The communication module 60 is a communication device that can be controlled by the microprocessor 61 of the electronic control unit 49 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 60 may be located either inside or outside the electronic control unit 49. The external device may be, for example, the base station 10 or the user terminal 20 described above. Furthermore, the communication module 60 may be, for example, at least one of the base station 10 and the user terminal 20 described above (or may function as at least one of the base station 10 and the user terminal 20).

[0418] The communication module 60 may transmit at least one of signals from the above-mentioned various sensors 50-58 input to the electronic control unit 49, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 59 to an external device via wireless communication. The electronic control unit 49, the various sensors 50-58, the information service unit 59, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 60 may include information based on the above-mentioned input.

[0419] The communication module 60 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from an external device and displays it on an information service unit 59 provided in the vehicle. The information service unit 59 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH received by the communication module 60 (or data / information decoded from the PDSCH)).

[0420] Furthermore, the communication module 60 stores various information received from external devices in a memory 62 that can be used by the microprocessor 61. Based on the information stored in the memory 62, the microprocessor 61 may control the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, various sensors 50-58, and the like provided in the vehicle 40.

[0421] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple user terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the user terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "sidelink"). For example, terms such as an uplink channel and a downlink channel may be read as a sidelink channel.

[0422] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station 10 may be configured to have the functions of the user terminal 20 described above.

[0423] In the present disclosure, an operation described as being performed by a base station may be performed by its upper node in some cases. It is apparent that in a network including one or more network nodes having a base station, various operations performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME), a Serving-Gateway (S-GW), etc.), or a combination thereof.

[0424] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, the order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0425] Each aspect / embodiment described in the present disclosure may be a technology other than Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG (x is, for example, an integer or decimal number)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (Wi-Fi (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 (WiMAX (registered trademark)), IEEE 802.30 (WiMAX (registered trademark)), IEEE 802.31 (Wi-Fi (registered trademark)), IEEE 802.32 (WiMAX (registered trademark)), IEEE 802.33 (WiMAX (registered trademark)), IEEE 802. The present invention may be applied to systems that use IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable wireless communication methods, or to next-generation systems that are expanded, modified, created, or defined based on these. Furthermore, the present invention may be applied to a combination of multiple systems (e.g., a combination of LTE or LTE-A and 5G).

[0426] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0427] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0428] The term "determining" as used in this disclosure may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., looking up in a table, database, or another data structure), ascertaining, etc.

[0429] Additionally, "determining" may be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), etc.

[0430] Also, "determination" may be considered to be "deciding" resolving, selecting, choosing, establishing, comparing, etc. In other words, "determination" may be considered to be "deciding" some action.

[0431] Furthermore, "judgment (decision)" may be read as "assuming," "expecting," "considering," or the like.

[0432] The "maximum transmit power" in this disclosure may mean the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0433] As used in this disclosure, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access."

[0434] In this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, etc., as some non-limiting and non-exhaustive examples.

[0435] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0436] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0437] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0438] In the present disclosure, terms such as "less than or equal to," "less than," "greater than," "more than," "equal to," etc. may be interchangeable. Furthermore, in the present disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "fast," "slow," "wide," "narrow," etc. may be interchangeable, not limited to the positive, comparative, and superlative. Furthermore, in the present disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "fast," "slow," "wide," "narrow," etc. may be interchangeable, not limited to the positive, comparative, and superlative, as expressions with "i-th" (i is an arbitrary integer) attached (for example, "highest" may be interchangeable with "i-th highest").

[0439] In this disclosure, the terms "of," "for," "regarding," "related to," "associated with," etc. may be read interchangeably.

[0440] Although the invention according to the present disclosure has been described in detail above, it is clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the description of the claims. Therefore, the description of the present disclosure is intended to be illustrative and explanatory and does not impose any limiting meaning on the invention according to the present disclosure.

Claims

1. A receiver that receives upper layer signaling related to switching between a first table of demodulation reference signal (DMRS) port instructions for an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) corresponding to a layer count of four or less and a second table of DMRS port instructions for a PUSCH corresponding to a layer count of more than four layers, and downlink control information (DCI) for scheduling the PUSCH; A terminal having a control unit that selects a table to be used for referring to the antenna port field of the DCI from one of the first table and the second table based on the higher layer signaling.

2. The terminal described in claim 1, wherein the control unit determines the number of bits of the antenna port field based on the setting of the upper layer signaling.

3. The terminal described in claim 1, further having a transmitting unit that reports UE capability information indicating that it supports dynamic switching between the first table and the second table.

4. A step of receiving upper layer signaling regarding switching between a first table regarding demodulation reference signal (DMRS) port instructions for an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) corresponding to a layer count of four or less and a second table regarding DMRS port instructions for a PUSCH corresponding to a layer count of more than four layers, and downlink control information (DCI) for scheduling the PUSCH; A wireless communication method for a terminal, comprising: a step of selecting a table to be used for referring to the antenna port field of the DCI from one of the first table and the second table based on the higher layer signaling.

5. A transmitter that transmits to a terminal higher layer signaling related to switching between a first table related to demodulation reference signal (DMRS) port indication for an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) corresponding to a layer count of four or less and a second table related to DMRS port indication for a PUSCH corresponding to a layer count of more than four layers, and downlink control information (DCI) for scheduling the PUSCH; A base station having a control unit that determines a DMRS port for the PUSH based on a table used to refer to an antenna port field of the DCI, the table being selected from one of the first table and the second table based on the higher layer signaling.

6. A system having a terminal and a base station, The terminal includes a receiving unit that receives higher layer signaling related to switching between a first table related to demodulation reference signal (DMRS) port indication for an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) corresponding to a layer number of four or less and a second table related to DMRS port indication for a PUSCH corresponding to a layer number of more than four layers, and downlink control information (DCI) for scheduling the PUSCH; A control unit that selects a table to be used for referring to the antenna port field of the DCI from one of the first table and the second table based on the higher layer signaling, The base station includes a transmission unit that transmits the higher layer signaling and the DCI to the terminal; A control unit that determines a DMRS port for the PUSCH based on the table selected from one of the first table and the second table based on the higher layer signaling.