Terminals, wireless communication methods, base stations and systems

Abstract

A terminal according to one aspect of the present disclosure comprises: a reception unit that receives one or more antenna port instructions in one or more code division multiplexing (CDM) groups for a demodulation reference signal (DMRS) to which a frequency domain orthogonal cover code (FD-OCC) longer than 2 is applied; and a control unit that determines, on the basis of the instruction, whether to assume that the remaining antenna ports of the one or more antenna ports in the one or more CDM groups are allocated for transmission of a downlink shared channel to another terminal. This one aspect of the present disclosure makes it possible to use the appropriate number of DMRS ports.

Description

[Technical Field]

[0001] This disclosure relates to terminals and wireless communication methods in next-generation mobile communication systems. 、 base station and system Regarding. [Background technology]

[0002] Long Term Evolution (LTE) was specified for Universal Mobile Telecommunications System (UMTS) networks with the aim of achieving even higher data rates and lower latency (Non-Patent Literature 1). Furthermore, LTE-Advanced (3GPP Rel.10-14) was specified for the aim of further increasing capacity and sophistication of LTE (Third Generation Partnership Project (3GPP®) Release (Rel.) 8, 9).

[0003] Successor systems to LTE (for example, 5th generation mobile communication system (5G), 5G+ (plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel.15 and later, etc.) are also being considered. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 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 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Future wireless communication systems (e.g., NR) incorporate beam management techniques. For example, in NR, beam formation (or utilization) is being considered at least one of the base station and the user terminal (User Equipment (UE)).

[0006] On the other hand, multiple port reference signals (e.g., demodulation reference signals (DMRS)) are used for purposes such as orthogonalization of layers. Future wireless communication systems will require an increase in the number of DMRS ports compared to existing specifications. However, how to increase the number of DMRS ports has not yet been thoroughly investigated. If an appropriate number of DMRS ports cannot be used, communication throughput and communication quality may deteriorate.

[0007] Therefore, this disclosure relates to a terminal that uses an appropriate number of DMRS ports, and a wireless communication method. 、 base station and system One of the objectives is to provide [this]. [Means for solving the problem]

[0008] A terminal according to one aspect of the present disclosure includes a receiving unit that receives instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for a demodulated reference signal (DMRS) to which a frequency domain orthogonal cover code (FD-OCC) longer than 2 is applied, and determines that if the instructions indicate two antenna ports from two CDM groups, the remaining antenna ports are not associated with transmitting a physical downlink sharing channel (PDSCH) to another terminal. Furthermore, if the instruction indicates one antenna port, it is determined that the remaining antenna ports may be associated with transmitting PDSCH to another terminal. It has a control unit and [Effects of the Invention]

[0009] According to one aspect of the present disclosure, an appropriate number of DMRS ports can be used.

Brief Description of the Drawings

[0010] [Figure 1] FIG. 1 shows an example of an existing DMRS port table for DMRS setting type 1. [Figure 2] FIG. 2 shows an example of an existing DMRS port table for DMRS setting type 2. [Figure 3] FIGS. 3A to 3D show an example of an FD-OCC of length 4 / 6. [Figure 4] FIG. 4 shows an example of an FD-OCC of length 4. [Figure 5] FIG. 5 shows an example of a DMRS port index corresponding to an existing FD-OCC. [Figure 6] FIG. 6 shows an example of a DMRS port index corresponding to a new FD-OCC. [Figure 7] FIG. 7 shows an example of a DMRS port index corresponding to a new FD-OCC. [Figure 8] FIG. 8 shows an example of a DMRS port index corresponding to an existing FD-OCC and a DMRS port index corresponding to a new FD-OCC. [Figure 9] FIG. 9 shows an example of an antenna port table for DMRS setting type 1 and single-symbol DMRS. [Figure 10] FIG. 10 shows an example of an antenna port table for DMRS setting type 1 and double-symbol DMRS. [Figure 11] FIG. 11 shows an example of an antenna port table for DMRS setting type 2 and single-symbol DMRS. [Figure 12] FIG. 12 shows an example of the first part of an antenna port table for DMRS setting type 2 and double-symbol DMRS. [Figure 13]FIG. 13 shows an example of the second part of the antenna port table for DMRS configuration type 2 and double-symbol DMRS. [Figure 14] FIGS. 14A to 14E show an example of the existing MU-MIMO scheduling constraints for single-symbol DMRS. [Figure 15] FIGS. 15A to 15C show an example of the existing MU-MIMO scheduling constraints for double-symbol DMRS. [Figure 16] FIGS. 16A to 16D show an example of Case 1-1. [Figure 17] FIGS. 17A to 17C show an example of Case 1-2. [Figure 18] FIGS. 18A to 18D show an example of Case 1-3. [Figure 19] FIGS. 19A to 19D show an example of Case 1-4. [Figure 20] FIGS. 20A to 20D show an example of Case 1-5. [Figure 21] FIGS. 21A to 21C show another example of Case 1-5. [Figure 22] FIGS. 22A to 22D show an example of Case 1-6. [Figure 23] FIGS. 23A and 23B show another example of Case 1-6. [Figure 24] FIGS. 24A to 24C show an example of Case 1-7. [Figure 25] FIGS. 25A to 25C show an example of Case 1-8. [Figure 26] FIGS. 26A and 26B show an example of a variation of Embodiment #1. [Figure 27] FIGS. 27A to 27D show an example of Case 2-1. [Figure 28] FIGS. 28A to 28C show an example of a variation of Case 2-1. [Figure 29] FIGS. 29A to 29D show an example of Case 2-2. [Figure 30] FIG. 30 is a diagram showing an example of the schematic configuration of a wireless communication system according to an embodiment. [Figure 31] Figure 31 shows an example of the configuration of a base station according to one embodiment. [Figure 32] Figure 32 shows an example of the configuration of a user terminal according to one embodiment. [Figure 33] Figure 33 shows an example of the hardware configuration of a base station and a user terminal according to one embodiment. [Figure 34] Figure 34 shows an example of a vehicle according to one embodiment. [Modes for carrying out the invention]

[0011] (Beam management) NR incorporates beam management techniques. For example, NR considers forming (or utilizing) a beam at at least one of the base station and the UE.

[0012] By applying beamforming (BF), it is expected that the difficulty in ensuring coverage as carrier frequencies increase will be mitigated, and radio wave propagation loss will be reduced.

[0013] BF (Broadcast Field) is a technique that uses, for example, a multi-element antenna to control (also called precoding) the amplitude / phase of the signal transmitted or received from each element, thereby forming a beam (antenna directivity). Such a multi-element antenna used in Multiple Input Multiple Output (MIMO) systems is also known as massive MIMO.

[0014] Beam sweeping may be performed on both the transmitting and receiving sides to select an appropriate pair from multiple candidate patterns of transmit and receive beam pairs. The transmit and receive beam pair may be called a beam pair and may be identified as a beam pair candidate index.

[0015] Furthermore, in beam management, instead of using a single beam, multiple levels of beam control, such as a rough beam and a fine beam, may be employed.

[0016] BF (Bass Flow) can be classified into digital BF and analog BF. Digital BF and analog BF may also be called digital precoding and analog precoding, respectively.

[0017] Digital BF is a method of performing pre-coding signal processing (for digital signals) on the baseband, for example. In this case, parallel processing such as Inverse Fast Fourier Transform (IFFT), Digital to Analog Converter (DAC), and Radio Frequency (RF) is required for each antenna port (or RF chain). On the other hand, a number of beams corresponding to the number of RF chains can be formed at any given time.

[0018] Analog BF is a method that uses a phase shifter on the RF signal, for example. Although analog BF cannot form multiple beams at the same time, it is easy to configure and inexpensive to implement because it only rotates the phase of the RF signal.

[0019] Furthermore, a hybrid BF configuration combining digital and analog BFs is also feasible. While the introduction of large-scale MIMO is being considered for NR, performing the enormous number of beamforming operations solely with digital BFs would result in a costly circuit configuration, so the use of a hybrid BF configuration is also being considered.

[0020] (TCI, spatial relations, QCL) In NR, it is considered to control the reception processing (e.g., at least one of reception, demapping, demodulation, and decoding) and transmission processing (e.g., at least one of transmission, mapping, precoding, modulation, and encoding) of at least one of a signal and a channel (which may be denoted as signal / channel; hereafter, "A / B" may similarly be read as "at least one of A and B") based on the Transmission Configuration Indication state (TCI state).

[0021] The TCI state may represent the one applied to the downlink signal / channel. The equivalent of the TCI state applied to the uplink signal / channel may be expressed as a spatial relation.

[0022] TCI status refers to information about signal / channel quasi-co-location (QCL), and may also be called spatial reception parameters or spatial relation information (SRI). TCI status may be set for each channel or signal in the UE.

[0023] QCL is an index that indicates the statistical properties of a signal / channel. For example, if two signals / channels have a QCL relationship, it may mean that we can assume that at least one of the following is identical between these different signals / channels: Doppler shift, Doppler spread, average delay, delay spread, and spatial parameter (e.g., spatial Rx parameter).

[0024] The spatial reception parameters may correspond to the UE's received beam (e.g., the received analog beam), and the beam may be identified based on the spatial QCL. In this disclosure, QCL (or at least one element of QCL) may be interpreted as sQCL (spatial QCL).

[0025] QCL may have multiple types (QCL types). For example, there may be four QCL types A and D that differ in the parameters (or parameter sets) that can be assumed to be the same, and these parameters (which may also be called QCL parameters) are shown below: QCL Type A: Doppler shift, Doppler spread, mean delay, and delay spread. QCL Type B: Doppler shift and Doppler spread, • QCL Type C: Doppler shift and mean delay, • QCL Type D: Spatial reception parameters.

[0026] Types A through C may correspond to QCL information related to synchronization processing of at least one of time and frequency, and Type D may correspond to QCL information related to beam control.

[0027] The assumption by the UE that a given control resource set (CORESET), channel, or reference signal is in a specific QCL (e.g., QCL type D) relationship with another CORESET, channel, or reference signal may be called a QCL assumption.

[0028] The UE may determine at least one of the transmit beam (Tx beam) and receive beam (Rx beam) of a signal / channel based on the TCI state or QCL assumption of the signal / channel.

[0029] The TCI state may, for example, be information regarding the QCL between the target channel (or the reference signal (RS) for that channel) and another signal (for example, another downlink reference signal (DL-RS)). The TCI state may be set (indicated) by upper-layer signaling, physical layer signaling, or a combination thereof.

[0030] In this disclosure, the upper-layer signaling may be, for example, Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, or a combination thereof.

[0031] MAC signaling may use, for example, MAC Control Elements (MAC CEs) or MAC Protocol Data Units (PDUs). Broadcast information may also include, for example, Master Information Blocks (MIBs), System Information Blocks (SIBs), Remaining Minimum System Information (RMSIs), or Other System Information (OSIs).

[0032] Physical layer signaling may include, for example, Downlink Control Information (DCI).

[0033] The channel on which the TCI state is set (specified) may be at least one of the following: a Physical Downlink Shared Channel (PDSCH), a Physical Downlink Control Channel (PDCCH), a Physical Uplink Shared Channel (PUSCH), or a Physical Uplink Control Channel (PUCCH).

[0034] Furthermore, the RS (DL-RS) that has a QCL relationship with the channel may be at least one of the following: a Synchronization Signal Block (SSB), a Channel State Information Reference Signal (CSI-RS), or a Sounding Reference Signal (SRS). Alternatively, the DL-RS may be a CSI-RS used for tracking (also called a Tracking Reference Signal (TRS)), or a reference signal (also called a QCL) used for QCL detection.

[0035] An SSB is a signal block that includes at least one of a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). An SSB may also be called an SS / PBCH block.

[0036] The TCI state information element (RRC's "TCI-state IE") set by upper-layer signaling may include one or more QCL information ("QCL-Info"). The QCL information may include at least one of the following: information about the DL-RS with which it has a QCL relationship (DL-RS relationship information) and information indicating the QCL type (QCL type information). The DL-RS relationship information may include information such as the DL-RS index (e.g., SSB index, Non-Zero-Power (NZP) CSI-RS resource ID (Identifier)), the index of the cell where the RS is located, and the index of the Bandwidth Part (BWP) where the RS is located.

[0037] (Advancements in MIMO technology and beams) Incidentally, while MIMO technology has so far been used in frequency bands lower than 6 GHz, its application to frequency bands higher than 6 GHz is being considered for the future.

[0038] Frequency bands lower than 7.125 GHz may be called Frequency Range (FR) 1, etc. Frequency bands higher than 7.125 GHz / 24.250 GHz may be called FR2, FR2-1, FR2-2, millimeter wave (mmW), FR4, etc.

[0039] The maximum number of MIMO layers is assumed to be limited by the antenna size.

[0040] Even with mmW, by utilizing higher-order MIMO and having multiple UEs cooperate, the degrees of freedom and diversity of MIMO multiplexing can be improved, which in turn is expected to lead to improved throughput.

[0041] Thus, in future wireless communication systems (for example, NR from Rel-17 onwards), even at high frequencies (for example, FR2), it is anticipated that operation using only digital beams without analog beams (which may also be called full digital operation) or operation that predominantly uses digital beams will be employed.

[0042] For example, in fully digital operation, applying orthogonal precoding (or orthogonal beam, digital beam) to multiple UEs simultaneously can be expected to improve frequency utilization efficiency. If digital beam cannot be applied properly, interference between UEs will increase, leading to a deterioration in communication quality (or a decrease in cell capacity). Note that the term "orthogonal" in this disclosure may be interpreted as "quasi-orthogonal."

[0043] If a base station (which may be interpreted as a transmission / reception point (TRP), panel, etc.) can only transmit one beam at a time, the base station switches beams to transmit and receive to the UE. If a base station can transmit multiple beams at a time, it can transmit and receive with multiple UEs simultaneously using different beams.

[0044] Even if base stations become fully digital, as long as Rel.15 UEs exist, Rel.15 UEs should be accommodated (supported).

[0045] (DMRS) The front-loaded DMRS is the first (first symbol or near the first symbol) DMRS for faster demodulation. Additional DMRS can be set by the RRC for fast-moving UEs or high modulation and coding scheme (MCS) / rank. The frequency position of the additional DMRS is the same as that of the front-loaded DMRS.

[0046] For the time domain, either 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 set by a parameter (dmrs-TypeA-Position) in the MIB or Common Serving Cell Configuration (ServingCellConfigCommon). DMRS position 0 (reference point l) means the first symbol in 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) means the first symbol in the PDSCH / PUSCH or each frequency hop.

[0047] The location of DMRS is defined by a specification table and depends on the duration of PDSCH / PUSCH. The location of additional DMRS is fixed.

[0048] For each frequency domain, either (PDSCH / PUSCH)DMRS configuration type 1 or 2 is set. DMRS configuration type 1 has a comb structure and is applicable to both CP-OFDM (transport precoding disabled) and DFT-S-OFDM (transport precoding enabled). DMRS configuration type 2 is applicable only to CP-OFDM.

[0049] Single-symbol DMRS or double-symbol DMRS is set.

[0050] Single-symbol DMRS is commonly 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 cases where frequency hopping is enabled and disabled. If the maximum number (maxLength) in the uplink DMRS configuration (DMRS-UplinkConfig) is not set, single-symbol DMRS is used.

[0051] 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 supports cases where frequency hopping is disabled. If the maximum number (maxLength) in the uplink DMRS configuration (DMRS-UplinkConfig) is 2 (len2), whether it is single-symbol DMRS or double-symbol DMRS is determined by DCI or configured grant.

[0052] Based on the above, the following combinations of DMRS configuration patterns are possible. • 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

[0053] Multiple DMRS ports mapped to the same RE (Time and Frequency Resource) are called a DMRS code division multiplexing (CDM) group.

[0054] 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 by a length 2 FD OCC. Between multiple DMRS CDM groups (two DMRS CDM groups), two DMRS ports are multiplexed by FDM.

[0055] 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 a length 2 FD OCC, 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.

[0056] Six DMRS ports can be used for DMRS configuration type 2 and single-symbol DMRS. Within each DMRS CDM group, two DMRS ports are multiplexed by a length 2 FD OCC. Between multiple DMRS CDM groups (three DMRS CDM groups), three DMRS ports are multiplexed by FDM.

[0057] Twelve DMRS ports can be used for DMRS configuration type 2 and double-symbol DMRS. Within each DMRS CDM group, two DMRS ports are multiplexed by a length 2 FD OCC, 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.

[0058] Here, we have shown an example of DMRS mapping type B, but DMRS mapping type A is similar.

[0059] In the parameters for PDSCH DMRS (existing table, existing DMRS port table, Figure 1), DMRS ports 1000-1007 can be used for DMRS configuration type 1, and DMRS port 1000-1011 can be used for DMRS configuration type 2.

[0060] In the parameters for PUSCH DMRS (existing table, existing DMRS port table, Figure 2), DMRS ports 0-7 can be used for DMRS configuration type 1, and DMRS ports 0-11 can be used for DMRS configuration type 2.

[0061] (Reference signal port) Multiple port reference signals (e.g., demodulation reference signal (DMRS), CSI-RS) are used for purposes such as orthogonalizing the MIMO layer.

[0062] For example, for Single User MIMO (SU-MIMO), different DMRS ports / CSI-RS ports may be configured for each layer. For Multi User MIMO (MU-MIMO), different DMRS ports / CSI-RS ports may be configured for each layer within a single UE, and for each UE as well.

[0063] Furthermore, using a number of CSI-RS ports greater than the number of layers used in the data is expected to enable more accurate measurement of channel status based on the CSI-RS, thereby contributing to improved throughput.

[0064] In Rel.15 NR, multi-port DMRS can support up to 8 ports for Type 1 DMRS (in other words, DMRS configuration type 1) and up to 12 ports for Type 2 DMRS (in other words, DMRS configuration type 2) by using technologies such as Frequency Division Multiplexing (FDM), Frequency Domain Orthogonal Cover Code (FD-OCC), and Time Domain OCC (TD-OCC).

[0065] In Rel.15 NR, the above FDM uses a comb-shaped transmission frequency pattern (comb-shaped resource set). The above FD-OCC uses Cyclic Shift (CS). Furthermore, the above TD-OCC can only be applied to double-symbol DMRS.

[0066] The terms OCC in this disclosure may be interpreted interchangeably with orthogonal codes, orthogonalization, cyclic shifts, and the like.

[0067] The DMRS type may also be called the DMRS Configuration type.

[0068] Among DMRSs, those that perform resource mapping in units of two consecutive (adjacent) symbols may be called double-symbol DMRS, and those that perform resource mapping in units of one symbol may be called single-symbol DMRS.

[0069] Both DMRSs 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, while a DMRS mapped additionally to any other position may be called an additional DMRS.

[0070] 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).

[0071] In the case of DMRS configuration type 1 and double symbol DMRS, Comb, CS, and TD-OCC may be used for orthogonalization. For example, up to 8 APs may be supported using two types of Comb, two types of CS, and TD-OCC ({1,1} and {1,-1}).

[0072] 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 orthogonal codes (2-FD-OCC) to two adjacent resource elements (REs) in the frequency direction.

[0073] 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 orthogonal codes (2-FD-OCC) to two frequency-adjacent REs and TD-OCC ({1,1} and {1,-1}) to two time-adjacent REs.

[0074] Furthermore, in Rel.15 NR, multi-port CSI-RS supports up to 32 ports by using methods such as FDM, Time Division Multiplexing (TDM), Frequency Domain OCC, and Time Domain OCC. The same methods as those used for DMRS described above may also be applied to orthogonalize the CSI-RS.

[0075] Now, the group of DMRS ports orthogonalized by FD-OCC / TD-OCC as described above is also called a Code Division Multiplexing (CDM) group.

[0076] Different CDM groups are orthogonal due to FDM. However, within the same CDM group, channel variations may disrupt the orthogonality of the applied OCC. In this case, receiving signals within the same CDM group at different receiving powers may cause a near-far problem, potentially compromising orthogonality.

[0077] Here, we will explain the TD-OCC / FD-OCC of DMRS in Rel.15 NR. DMRS mapped to a Resource Element (RE) has FD-OCC parameters (which may also be called sequence elements, etc.) in the DMRS sequence. f (k') and the TD-OCC parameters (which may also be called sequence elements, etc.) w t It may also be a sequence obtained by multiplying (l') by .

[0078] Both the TD-OCC and FD-OCC of the DMRS in Rel.15 NR correspond to OCCs with a sequence length (which may also be called OCC length) of 2. Therefore, the possible values ​​for k' and l' are both 0 and 1. By multiplying this FD-OCC by RE units, two DMRS ports can be multiplexed using the same time and frequency resources (2RE). By applying both FD-OCC and TD-OCC, four DMRS ports can be multiplexed using the same time and frequency resources (4RE).

[0079] The two existing DMRS port tables for PDSCH mentioned above (associating antenna port index (number) with parameters) correspond to DMRS configuration types 1 and 2, respectively. Note that 'p' indicates the antenna port number, and 'Δ' indicates the parameter for shifting (offsetting) frequency resources.

[0080] For example, for antenna ports 1000 and 1001, by applying {w f (0), w f (1)} = {+1, +1} and {w f (0), w f (1)} = {+1, -1} respectively, they are orthogonalized using FD - OCC.

[0081] For antenna ports 1000 - 1001 and antenna ports 1002 - 1003 (and in the case of type 2, antenna ports 1004 - 1005 as well), by applying different values of Δ, FDM is applied. Therefore, antenna ports 1000 - 1003 (or 1000 - 1005) corresponding to single - symbol DMRS are orthogonalized using FD - OCC and FDM.

[0082] For type 1 antenna ports 1000 - 1003 and antenna ports 1004 - 1007, by applying {w t (0), w t (1)} = {+1, +1} and {w t (0), w t (1)} = {+1, -1} respectively, they are orthogonalized using TD - OCC. Therefore, antenna ports 1000 - 1007 (or 1000 - 1011) corresponding to double - symbol DMRS are orthogonalized using FD - OCC, TD - OCC and FDM.

[0083] For only CP - OFDM, (without increasing the DMRS overhead,) defining a larger number of orthogonal DMRS ports for DL / UL MU - MIMO, making the design common between DL and UL DMRS, up to 24 orthogonal DMRS ports, doubling the maximum number of orthogonal DMRS ports for both single - symbol DMRS and double - symbol DMRS for each applicable DMRS setting type, are being considered.

[0084] In Rel.15, the following cases 1 to 4 can be set. [Case 1] Single Symbol DMRS with DMRS Configuration Type 1 The total number of DMRS ports is 2 (by comb / FDM) × 2 (by FD OCC) = 4 ports. [Case 2] Double symbol DMRS with DMRS configuration type 1 The total number of DMRS ports is 2 (by comb / FDM) × 2 (by FD OCC) × 2 (by TD OCC) = 8 ports. [Case 3] Single Symbol DMRS with DMRS Configuration Type 2 The total number of DMRS ports is 3 (by FDM) × 2 (by FD OCC) = 6 ports. [Case 4] Double symbol DMRS with DMRS configuration type 2 The total number of DMRS ports is 3 (by comb) × 2 (by FD OCC) × 2 (by TD OCC) = 12 ports.

[0085] In Rel.18, it is being considered to double the total number of DMRS ports for cases 1, 2, 3, and 4, to 8, 16, 12, and 24, respectively.

[0086] To increase the number of DMRS ports, the following five options (methods for increasing the number of DMRS ports) are being considered.

[0087] <Option 1> • Introduction of new OCCs with a longer length than existing OCCs (e.g., 4 or 6). Option 1 involves considering factors such as the potential for performance degradation with large delay spreads, potential scheduling limitations, and backward compatibility.

[0088] <Option 2> • Use of TD-OCC on multiple discontinuous DMRS symbols (e.g., TD-OCC on front-loaded DMRS / additional DMRS). Option 2 involves considering potential performance degradation at high UE speeds, scheduling limitations (e.g., how frequency hopping is applied), potential limitations on DMRS configuration (e.g., the number of additional DMRSs is limited), and backward compatibility.

[0089] <Option 3> • Increase the number of CDM groups (for example, increase the number of comb / FDM groups). Option 3 considers factors such as the potential for performance degradation when the delay spread is large, and backward compatibility.

[0090] <Option 4> • Reuse symbols for additional DMRS to increase the number of orthogonal DMRS ports. Option 4 involves considering potential performance degradation at high UE speeds, potential limitations on DMRS settings (e.g., a limit on the number of additional DMRSs), and backward compatibility.

[0091] <Option 5> • Use of TD-OCC on discontinuous multiple DMRS symbols in combination with FD-OCC / FDM (reusing additional DMRS symbols to improve channel estimation performance). Option 5 involves considering potential performance degradation at high UE speeds, potential scheduling limitations (e.g., how frequency hopping is applied), potential limitations on DMRS configuration (e.g., the number of additional DMRSs is limited), and backward compatibility.

[0092] In Option 1, the new FD-OCC for the PDSCH / PUSCH DMRS may conform to at least one of the following options for the new DMRS configuration type 1. <<Option 1-1>> A new FD-OCC of length 6 is applied to 6RE of DMRS within one PRB in one CDM group. <<Option 1-2>> Within a single CDM group, a new FD-OCC of length 4 is applied to 4REs of DMRS, either within a single PRB or spanning multiple consecutive PRBs.

[0093] In Option 1, for PDSCH / PUSCH DMRS, a new FD-OCC of length 4 is applied to the 4REs of the DMRS in one PRB within one CDM group for new DMRS configuration type 2. A new FD-OCC of length 6 may also be supported for new DMRS configuration type 2.

[0094] In this disclosure, existing FD-OCC#0 = [+1 +1] and existing FD-OCC#1 = [+1 -1] may also be used.

[0095] A new FD-OCC may be any of the following OCCs:

[0096] [OCC-a] An OCC of length 4 based on a 4x4 Walsh matrix (sequence). As shown in the example in Figure 3A, for an OCC index i = {0, 1, 2, 3}, four sequences are obtained.

[0097] [OCC-b] OCC of length 4 based on cyclic shift. As shown in the example in Figure 3B, four sequences can be obtained by using the cyclic shift {i·0,i·π / 2,i·π,i·3π / 2} for OCC index i={0,1,2,3}.

[0098] [OCC-c] As shown in the example in Figure 3C, OCC-b is a case where OCC indices 1 and 2 of the OCC are swapped.

[0099] [OCC-d] An OCC of length 6 based on FFT (DFT). As shown in the example in Figure 3D, for an OCC index i = {0, 1, 2, 3, 4, 5}, six sequences are obtained from each row of the DFT matrix.

[0100] [OCC-e] OCC-a and OCC-c are OCCs of length 4 that consist of repeating OCCs of length 2 (existing FD-OCCs). As shown in the example in Figure 4, the first and second halves of OCC#0 and #1 of length 4 (OCCs corresponding to OCC indices 0 and 1) are the same as OCC#0 and #1 of length 2 (OCCs corresponding to OCC indices 0 and 1).

[0101] In this disclosure, the OCC (FD-OCC / TD-OCC) corresponding to OCC index i may be referred to as OCC#i.

[0102] Some of the new FD-OCC series may be associated with existing DMRS port indexes.

[0103] When an FD-OCC of length 2 is used, an existing DMRS port table may be used. The existing DMRS port table for DMRS configuration type 1 may be the DMRS port table for DMRS configuration type 1 shown in Figure 5 or Figure 2.

[0104] If the new FD-OCC is OCC-e, the new DMRS port table for DMRS configuration type 1 may be the DMRS port table shown in Figure 6. The new DMRS port table may indicate the DMRS ports (p is 0 or greater) corresponding to the new FD-OCC. At least some of the p values ​​in the new DMRS port table may overlap with the p values ​​in the existing DMRS port table. If the use of the new FD-OCC is configured / instructed, the UE may use the new DMRS port table; if the use of the new FD-OCC is not configured / instructed, the UE may use the existing DMRS port table. As in this example, the same DMRS port index (0 to 7 for existing DMRS ports and DMRS configuration type 1) may be used for DMRS ports with new FD-OCC#0 and 1 as for existing DMRS ports. A different DMRS port index (8 to 15 for new DMRS ports and DMRS configuration type 1) may be used for DMRS ports with new FD-OCC#2 and 3 than for existing DMRS ports.

[0105] Some of the new FD-OCC series may not be associated with existing DMRS port indexes.

[0106] As shown in the example in Figure 7, the new DMRS port table may only show the DMRS ports corresponding to the new FD-OCC. The DMRS port index corresponding to the new FD-OCC does not need to overlap with the DMRS port index corresponding to the existing FD-OCC.

[0107] As shown in the example in Figure 8, the new DMRS port table may include DMRS ports corresponding to existing FD-OCCs and DMRS ports corresponding to new FD-OCCs. In the new DMRS port table, the DMRS port index corresponding to the new FD-OCC may be added after the DMRS port index corresponding to the existing FD-OCC.

[0108] (MU-MIMO scheduling constraints) For MU-MIMO, multiple DMRSs are multiplexed for multiple UEs. Multiple DMRSs may use different OCCs within a single CDM group, or they may use different subcarriers (Combs) between multiple CDM groups. In CDM, problems arise due to the difference in distance from the base station to multiple UEs (near-far problem). Intersymbol interference does not occur in a flat-fading environment, but it does occur in a frequency-selective fading environment, degrading quality. To prevent this, MU-MIMO scheduling constraints (existing MU-MIMO scheduling constraints) are defined.

[0109] The following MU-MIMO scheduling constraints are defined for PDSCHs using DMRS configuration type 1. In DMRS configuration type 1, if a UE is scheduled to transmit one codeword (CW) and is assigned an antenna port mapping with index {2, 9, 10, 11, 30} in the existing antenna port table for DMRS configuration type 1, or if a UE is scheduled to transmit two CWs, the UE may assume that the remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE.

[0110] In the case where a DMRS CDM group without data is specified with a number of 1 and rank of 1 (1 DMRS port), there may be no restrictions within the same CDM group (a DMRS port from another UE may be CDM'd to that UE's DMRS port). In the case where a DMRS CDM group without data is specified with a number of 1 and rank of 2 (2 DMRS ports), all DMRS ports within the same CDM group are specified, so a DMRS port from another UE cannot be CDM'd to that UE's DMRS port within the same CDM group. In the case where a DMRS CDM group without data is specified with a number of 2 and rank of 3 (3 DMRS ports), three of the four DMRS ports within the two CDM groups are specified, so although one DMRS port is available, a DMRS port from another UE cannot be CDM'd to it. In the case where a DMRS CDM group without data is specified with a number of 2 and rank 4 (4 DMRS ports), all DMRS ports within the same CDM group are specified. Therefore, within the same CDM group, a DMRS port of one UE cannot be CDM'd to the DMRS port of another UE.

[0111] In cases where DMRS configuration type 1 and single symbol DMRS are configured (existing antenna port table in Figure 9), and the antenna port field value is {2} (number of DMRS CDM groups without data: 1, rank: 2), or the antenna port field value is {9, 10, 11} (number of DMRS CDM groups without data: 2, rank: 3), a DMRS port of another UE cannot be CDM'd to the designated DMRS port.

[0112] In the case where DMRS configuration type 1 and double symbol DMRS are configured (existing antenna port table in Figure 10), 1 CW is scheduled, and the antenna port field value is {2} (number of DMRS CDM groups without data 1, rank 2), or the antenna port field value is {9, 10, 11} (number of DMRS CDM groups without data 2, rank 3), another UE's DMRS port cannot be CDM'd to the designated DMRS port. In the case where DMRS configuration type 1 and double symbol DMRS are configured and 2 CW is scheduled, another UE's DMRS port cannot be CDM'd to the designated DMRS port.

[0113] The following MU-MIMO scheduling constraints are defined for PDSCHs using DMRS configuration type 2. In DMRS configuration type 2, if a UE is scheduled to transmit 1CW and is assigned an antenna port mapping with index {2,10,23} in the existing antenna port table for DMRS configuration type 2, or if a UE is scheduled to transmit 2CW, the UE may assume that the remaining orthogonal antenna ports are not associated with the transmission of another UE's PDSCH.

[0114] In the case where a DMRS CDM group without data is specified with a number of 2 and rank 4 (4 DMRS ports), all DMRS ports within the same CDM group are specified. Therefore, within the same CDM group, a DMRS port of one UE cannot be CDM'd to the DMRS port of that UE. In the case where a DMRS CDM group without data is specified with a number of 2 and rank 2 (2 DMRS ports are specified), one of the two DMRS ports is specified in each CDM group. Therefore, although one DMRS port is available in each CDM group, a DMRS port of another UE cannot be CDM'd to that port.

[0115] In the case where DMRS configuration type 2 and single symbol DMRS are configured (existing antenna port table in Figure 11), 1 CW is scheduled, and the antenna port field value is {2} (number of DMRS CDM groups without data 1, rank 2), or {10} (number of DMRS CDM groups without data 2, rank 4), or {23} (number of DMRS CDM groups without data 2, rank 2), another UE's DMRS port cannot be CDM'd to the designated DMRS port. In the case where DMRS configuration type 2 and single symbol DMRS are configured and 2 CW is scheduled, another UE's DMRS port cannot be CDM'd to the designated DMRS port.

[0116] In the case where DMRS configuration type 2 and double symbol DMRS are configured (existing antenna port tables in Figures 12 and 13), 1 CW is scheduled, and the antenna port field value is {2} (number of DMRS CDM groups without data: 1, rank: 2), or {10} (number of DMRS CDM groups without data: 2, rank: 4), or {23} (number of DMRS CDM groups without data: 2, rank: 2), another UE's DMRS port cannot be CDM'd to the designated DMRS port. In the case where DMRS configuration type 2 and double symbol DMRS are configured and 2 CW is scheduled, another UE's DMRS port cannot be CDM'd to the designated DMRS port.

[0117] MU-MIMO in Rel.15 is subject to several constraints, including whether or not the DMRS port of one UE is multiplexed to the DMRS port of another UE.

[0118] There are no restrictions on MU-MIMO (DMRS multiplexing using multiple different DMRS ports) spanning multiple different CDM groups.

[0119] MU-MIMO (DMRS multiplexing using multiple different DMRS ports) within a single CDM group is subject to several constraints, as follows: There are no restrictions for Rank 1 (1 specified DMRS port). • For rank 2 (2 specified DMRS ports), the FD-OCC length is 2, and there is a limitation because it is impossible to CDM another UE's DMRS to that UE's DMRS. • There is a limitation because, for rank 3 (1 specified DMRS port), the FD-OCC length is 2, making it impossible to CDM another UE's DMRS to that UE's DMRS.

[0120] In the example shown in Figure 14A, if a single-symbol DMRS is configured and one DMRS CDM group without data is specified to UE#0, and one DMRS port (DMRS port #0) corresponding to FD-OCC#0 within CDM group #0 can be specified to UE#1, enabling MU-MIMO.

[0121] In the example shown in Figure 14B, if a single-symbol DMRS is configured, and 1 DMRS CDM group without data is specified, along with two DMRS ports (DMRS ports #0 and #1) corresponding to FD-OCC #0 and #1 within CDM group #0, MU-MIMO is not possible.

[0122] In the example in Figure 14C, if a single-symbol DMRS is configured, and two DMRS CDM groups without data are specified, along with one DMRS port corresponding to FD-OCC#0 in CDM group #0 and one DMRS port corresponding to FD-OCC#0 in CDM group #1 (DMRS ports #0 and #2), then the remaining two DMRS ports in CDM groups #0 and #1 cannot be specified to UE#1, making MU-MIMO impossible.

[0123] In the example shown in Figure 14D, if a single-symbol DMRS is configured, and two DMRS CDM groups without data are specified, along with two DMRS ports corresponding to FD-OCC#0 and #1 in CDM group #0, and one DMRS port corresponding to FD-OCC#0 in CDM group #1 (DMRS ports #0, #1, and #2), then the remaining DMRS port in CDM group #1 cannot be specified to UE#1, making MU-MIMO impossible.

[0124] In the example in Figure 14E, if single symbol DMRS and DMRS configuration type 2 are set, and 3 DMRS CDM groups without data, two DMRS ports corresponding to FD-OCC#0 and #1 in CDM group #0, and one DMRS port corresponding to FD-OCC#0 in CDM group #1 (DMRS ports #0, #1, and #2) are directed to UE#0, then the remaining three DMRS ports in CDM groups #1 and #2 can be directed to UE#1, enabling MU-MIMO.

[0125] In the example in Figure 15A, if double symbol DMRS and DMRS setting type 1 are set, and 2 DMRS CDM groups without data, two DMRS ports corresponding to TD-OCC#0 and FD-OCC#0, #1 within CDM group #0, and one DMRS port corresponding to TD-OCC#1 and FD-OCC#0 within CDM group #0 (DMRS ports #0, #1, #4) are directed to UE#0, then the remaining five DMRS ports in CDM groups #0 and #1 can be directed to UE#1, enabling MU-MIMO.

[0126] In the example shown in Figure 15B, if double symbol DMRS and DMRS setting type 1 are set, and two DMRS CDM groups without data, two DMRS ports corresponding to TD-OCC#0, #1, and FD-OCC#0 in CDM group #0, and two DMRS ports corresponding to TD-OCC#0, #1, and FD-OCC#0 in CDM group #1 (DMRS ports #0, #2, #4, and #6) are directed to UE#0, then the remaining four DMRS ports in CDM groups #0 and #1 cannot be directed to UE#1, making MU-MIMO impossible.

[0127] In the example in Figure 15C, if double symbol DMRS and DMRS configuration type 2 are set, and 3 DMRS CDM groups without data, two DMRS ports corresponding to TD-OCC#0 and FD-OCC#0 and #1 in CDM group #0, and one DMRS port corresponding to TD-OCC#1 and FD-OCC#0 in CDM group #0 (DMRS ports #0, #1, and #6) are directed to UE#0, then the remaining nine DMRS ports in CDM groups #0, #1, and #2 can be directed to UE#1, enabling MU-MIMO.

[0128] However, the limitations of MU-MIMO when using new FD-OCCs longer than 2 are unclear. If such behavior is unclear, there is a risk of degradation in communication throughput / communication quality.

[0129] Therefore, the inventors conceived of a novel MU-MIMO operation based on FD-OCC.

[0130] The embodiments relating to this disclosure will be described in detail below with reference to the drawings. Each of the following embodiments (for example, each case) may be used individually or at least two may be applied in combination.

[0131] In this disclosure, "A / B" and "at least one of A and B" may be interpreted as mutually exclusive. In this disclosure, "A / B / C" may mean "at least one of A, B, and C".

[0132] In this disclosure, terms such as activate, deactivate, indicate, select, configure, update, and determine may be interpreted interchangeably. In this disclosure, terms such as support, control, controllable, operate, and operable may be interpreted interchangeably.

[0133] In this disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, higher-layer parameters, information elements (IE), settings, etc., may be interpreted interchangeably. In this disclosure, Medium Access Control elements (MAC Control Element (CE)), update commands, activation / deactivation commands, etc., may be interpreted interchangeably.

[0134] In this disclosure, the upper-layer signaling may be, for example, Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, or a combination thereof.

[0135] In this disclosure, MAC signaling may include, for example, MAC Control Elements (MAC CEs) and MAC Protocol Data Units (PDUs). Broadcast information may include, for example, Master Information Blocks (MIBs), System Information Blocks (SIBs), Remaining Minimum System Information (RMSIs), and Other System Information (OSIs).

[0136] In this disclosure, physical layer signaling may include, for example, Downlink Control Information (DCI) and Uplink Control Information (UCI).

[0137] In this disclosure, terms such as index, identifier (ID), indicator, and resource ID may be interpreted interchangeably. In this disclosure, terms such as sequence, list, set, group, cluster, and subset may be interpreted interchangeably.

[0138] In this disclosure, the terms used include: panel, panel group, beam, beam group, precoder, Uplink (UL) transmit entity, Transmission / Reception Point (TRP), base station, Spatial Relation Information (SRI), spatial relationship, 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 relationship group, Code Division Multiplexing (CDM) group, reference signal group, CORESET group, Physical Uplink Control Channel (PUCCH) groups, PUCCH resource groups, resources (e.g., reference signal resources, SRS resources), resource sets (e.g., reference signal resource sets), CORESET pools, 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 assumptions, etc., may be interpreted interchangeably.

[0139] In this disclosure, "to have the ability to..." may be interpreted as "to support / report the ability to..."

[0140] In this disclosure, DMRS port, antenna port, port, port number, and port index may be interpreted interchangeably.

[0141] In this disclosure, RB and PRB may be interpreted as mutually exclusive.

[0142] In this disclosure, OCC#i and the OCC corresponding to OCC index i may be interpreted as mutually interchangeable.

[0143] In each embodiment, the DMRS port table, the association of DMRS ports and parameters may be interchangeable. The parameters may include at least one of the CDM group, Δ, FD OCC, and TD OCC.

[0144] In each embodiment, the antenna port reference table, antenna port table, and the association of values ​​and parameters in the antenna port field may be interchangeable. The parameters may include at least one of the number of DMRS CDM groups without data, the DMRS port (number / index), and the number of preceding DMRS symbols.

[0145] (Wireless communication method) In each embodiment, an existing FD-OCC, an FD-OCC of length 2, w f (k'), may be read as interchangeable. In each embodiment, a new FD-OCC, an FD-OCC longer than 2, w f (k'), can be read interchangeably.

[0146] In each embodiment, the DMRS port index i and DMRS port #i may be interchangeable. In each embodiment, the DMRS ports corresponding to the new FD-OCC #0, #1, #2, #3 may be DMRS ports #i+0, #i+1, #i+2, #i+3, DMRS ports #i+0, #i+1, #j+0, #j+1, or DMRS ports #i+0, #i+1, #i+M+0, #i+M+1. i, j, and M may be multiples of 2, multiples of 4, or integers greater than or equal to 0. In each embodiment, an association between the FD / TD-OCC index and the DMRS port index may be used, such as the existing / new DMRS port table described above. For example, as shown in the new DMRS port table in Figure 6, if new DMRS ports (DMRS ports corresponding to new FD-OCC#2, #3) are indexed after existing DMRS ports (DMRS ports corresponding to new FD-OCC#0, #1), then M=8 may be used for DMRS configuration type 1, and M=12 for DMRS configuration type 2. For example, for DMRS configuration type 1 of single-symbol DMRS, new FD-OCC#0, #1, #2, and #3 in CDM group #0 may correspond to DMRS ports #0, #1, #8, and #9, respectively. For example, for DMRS configuration type 2 of single-symbol DMRS, new FD-OCC#0, #1, #2, and #3 in CDM group #0 may correspond to DMRS ports #0, #1, #12, and #13, respectively.

[0147] Each of the following embodiments may be applied to a PDSCH DMRS or to a PUSCH DMRS. The PUSCH DMRS port index may be represented as p, or the PDSCH DMRS port index may be represented as p+1000.

[0148] Each of the following embodiments may be applied to a single-symbol DMRS or a double-symbol DMRS. Each of the following embodiments may be applied to DMRS configuration type 1 or DMRS configuration type 2.

[0149] <Embodiment #1> This embodiment relates to MU-MIMO constraints for DMRS using novel FD-OCCs longer than 2 (whether a DMRS port of one UE is multiplexed to a DMRS port of another UE). This embodiment may also be applied to single-symbol DMRS.

[0150] There may be no restrictions on MU-MIMO (DMRS multiplexing using multiple different DMRS ports) spanning multiple different CDM groups.

[0151] MU-MIMO (DMRS multiplexing using multiple different DMRS ports) within a single CDM group or across multiple different CDM groups may be subject to at least one of the following cases (novel MU-MIMO scheduling constraints):

[0152] Case 1-1 For rank 1 (where 1 DMRS port is specified), MU-MIMO may be subject to one of the following constraints:

[0153] [Constraint A] There are no restrictions.

[0154] [Constraint B] The maximum number of UE / DMRS ports that are multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2, 3}.

[0155] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE.

[0156] [Constraint D] The constraint depends on the rank of another UE. That constraint may be either constraint D-1 or D-2 below. [[Constraint D-1]] Only option 1 is allowed, and option 2 is not allowed. [[Constraint D-2]] Only option 2 is allowed, and option 1 is not allowed.

[0157] [[Option 1]] The remaining DMRS ports are used for another UE of rank 1 / 2 / 3. [[Option 2]] The remaining DMRS ports are used for another Rank 1 UE.

[0158] Figure 16A shows an example of constraint D-2. In this example, UE#0 is directed to one (rank 1) DMRS port corresponding to the new FD-OCC#0 in CDM group #0. Another DMRS port of a different rank 1 UE may be multiplexed to this DMRS port. For example, UE#1 may be directed to one (rank 1) DMRS port corresponding to the new FD-OCC#1 in CDM group #0, UE#2 may be directed to one (rank 1) DMRS port corresponding to the new FD-OCC#2 in CDM group #0, and UE#3 may be directed to one (rank 1) DMRS port corresponding to the new FD-OCC#3 in CDM group #0. Constraint D-2 may be the same as the constraint in Rel. 15.

[0159] Figure 16B shows an example of constraint D-1. In this example, UE#0 is directed to one (rank 1) DMRS port corresponding to the new FD-OCC#0 in CDM group #0. This DMRS port may be multiplexed with DMRS ports of other UEs of rank 1 / 2. For example, UE#1 may be directed to two (rank 2) DMRS ports corresponding to the new FD-OCC#1 and #2 in CDM group #0, and UE#2 may be directed to one (rank 1) DMRS port corresponding to the new FD-OCC#3 in CDM group #0.

[0160] Figure 16C shows another example of constraint D-1. In this example, UE#0 is directed to one (rank 1) DMRS port corresponding to the new FD-OCC#0 in CDM group #0. This DMRS port may be multiplexed to the DMRS ports of another UE of rank 3. For example, UE#1 may be directed to three (rank 3) DMRS ports corresponding to the new FD-OCC#1, #2, and #3 in CDM group #0.

[0161] Figure 16D shows an example of constraint C. In this example, UE#0 is assigned one (rank 1) DMRS port corresponding to a new FD-OCC#0 within CDM group#0. Multiplexing of this DMRS port with orthogonal DMRS ports of other UEs may not be permitted.

[0162] Case 1-2 For rank 2 (where 2 DMRS ports are specified), MU-MIMO may be subject to one of the following constraints:

[0163] [Constraint A] There are no restrictions.

[0164] [Constraint B] The maximum number of UE / DMRS ports multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2}.

[0165] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE.

[0166] [Constraint D] The constraint depends on the rank of another UE. That constraint may be either constraint D-1 or D-2 below. [[Constraint D-1]] Only option 1 is allowed, and option 2 is not allowed. [[Constraint D-2]] Only option 2 is allowed, and option 1 is not allowed.

[0167] [[Option 1]] The remaining DMRS ports are used for another Rank 2 UE. [[Option 2]] The remaining DMRS ports are used for another Rank 1 UE.

[0168] Figure 17A shows an example of constraint C. In this example, UE#0 is assigned two (rank 2) DMRS ports corresponding to the new FD-OCC#0 and #1 within CDM group#0. Multiplexing of these DMRS ports with orthogonal DMRS ports of another UE is not permitted.

[0169] Figure 17B shows an example of constraint D-1. In this example, UE#0 is directed to two (rank 2) DMRS ports corresponding to the new FD-OCC#0 and #1 within CDM group#0. These DMRS ports may be multiplexed to the DMRS ports of another rank 2 UE. For example, UE#1 may be directed to two (rank 2) DMRS ports corresponding to the new FD-OCC#2 and #3 within CDM group#0.

[0170] Figure 17C shows an example of constraint D-2. In this example, UE#0 is directed to two (rank 2) DMRS ports corresponding to the new FD-OCC#0 and #1 within CDM group #0. These DMRS ports may be multiplexed with DMRS ports of another UE of rank 1. For example, UE#1 may be directed to one (rank 1) DMRS port corresponding to the new FD-OCC#2 within CDM group #0, and UE#2 may be directed to one (rank 1) DMRS port corresponding to the new FD-OCC#3 within CDM group #0.

[0171] Cases 1-3 For rank 3 (where 3 DMRS ports are specified), MU-MIMO may be subject to one of the following constraints:

[0172] [Constraint A] There are no restrictions.

[0173] [Constraint B] The maximum number of UE / DMRS ports that are multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2, 3}.

[0174] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE.

[0175] [Constraint D] The constraint depends on the rank of another UE. That constraint may be either constraint D-1 or D-2 below. [[Constraint D-1]] Only option 1 is allowed, and option 2 is not allowed. Further constraints may exist. For example, only another UE of rank 2 may be allowed, and the maximum number of UEs duplicated per CDM group may be 2. [[Constraint D-2]] Only option 2 is allowed, and option 1 is not allowed.

[0176] [[Option 1]] The remaining DMRS ports are used for another UE of a rank greater than 1. [[Option 2]] The remaining DMRS ports are used for another Rank 1 UE.

[0177] Figure 18A shows an example of constraint C. In this example, UE#0 is assigned three (rank 3) DMRS ports corresponding to the new FD-OCC#0, #1, and #2 within CDM group #0. Multiplexing of these DMRS ports with orthogonal DMRS ports of other UEs may not be permitted.

[0178] Figure 18B shows an example of constraint D-2. In this example, UE#0 is directed to three (rank 3) DMRS ports corresponding to the new FD-OCC#0, #1, and #2 within CDM group #0. These DMRS ports may be multiplexed to the DMRS ports of another UE with rank 1. For example, UE#1 may be directed to one (rank 1) DMRS port corresponding to the new FD-OCC#3 within CDM group #0.

[0179] Figure 18C shows an example of constraint D-1. In this example, UE#0 is directed to three (rank 3) DMRS ports corresponding to the new FD-OCCs #0, #1, and #2 in CDM group #0. These DMRS ports may be multiplexed with DMRS ports of other UEs of a rank greater than 1. For example, UE#1 may be directed to one DMRS port corresponding to the new FD-OCC #3 in CDM group #0, and four (rank 5) DMRS ports corresponding to the new FD-OCCs #0 through #3 in CDM group #1.

[0180] Figure 18D shows an example of constraint D-1. In this example, UE#0 is assigned three (rank 3) DMRS ports corresponding to the new FD-OCC#0, #1, and #2 in CDM group #0. These DMRS ports may be multiplexed with DMRS ports of other UEs of a rank greater than 1. For example, UE#1 may be assigned one DMRS port corresponding to the new FD-OCC#3 in CDM group #0 and one DMRS port (rank 2) corresponding to the new FD-OCC#0 in CDM group #1. For example, UE#2 may be assigned two (rank 2) DMRS ports corresponding to the new FD-OCC#5 and #4 in CDM group #0. For example, UE#3 may be assigned one (rank 1) DMRS port corresponding to the new FD-OCC#7 in CDM group #0.

[0181] Cases 1-4 For rank 4 (where 4 DMRS ports are specified), MU-MIMO may be subject to one of the following constraints:

[0182] [Constraint A] There are no restrictions.

[0183] [Constraint B] The maximum number of UE / DMRS ports that are multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2, 3}.

[0184] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. This constraint applies only if there are no available CDM groups for DMRS (data is FDM'd with DMRS); otherwise, another CDM group may be used for another UE.

[0185] [Constraint D] The constraint depends on the rank of another UE. That constraint may be either constraint D-1 or D-2 below. [[Constraint D-1]] Only option 1 is allowed, and option 2 is not allowed. Further constraints are possible. Constraint D-1 may be any of the following constraints D-1-1, D-1-2, or D-1-3. [[Constraint D-1-1]] Only option 1-1 below is allowed. [[Constraint D-1-2]] Only options 1-2 below are permitted. [[Constraint D-1-3]] Both options 1-1 and 1-2 below are permitted. [[Constraint D-2]] Only option 2 is allowed, and option 1 is not allowed.

[0186] [[Option 1]] The remaining DMRS ports are used for another UE of a rank greater than 1. [[Option 1-1]] The remaining DMRS ports are used for another UE of rank 4. [[Option 1-2]] The remaining DMRS ports are used for another Rank 2 UE. [[Option 2]] The remaining DMRS ports are used for another Rank 1 UE.

[0187] Figure 19A shows an example of constraint C. In this example, UE#0 is assigned four (rank 4) DMRS ports corresponding to new FD-OCC#0 to #3 within CDM group#0. Multiplexing of orthogonal DMRS ports of other UEs to these DMRS ports is not permitted.

[0188] Figure 19B shows an example of constraint D-1-1. In this example, UE#0 is directed to two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group#0, and two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group#1 (rank 4). These DMRS ports may be multiplexed with DMRS ports of another UE of rank 4. For example, UE#1 may be directed to two DMRS ports corresponding to the new FD-OCC#2 and #3 in CDM group#0, and two DMRS ports corresponding to the new FD-OCC#2 and #3 in CDM group#1 (rank 4).

[0189] Figure 19C shows an example of constraint D-1-2. In this example, UE#0 is directed to two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #0, and two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #1 (rank 4). These DMRS ports may be multiplexed with DMRS ports of another UE of rank 2. For example, UE#1 may be directed to two DMRS ports (rank 2) corresponding to the new FD-OCC#2 and #3 in CDM group #0. For example, UE#2 may be directed to two DMRS ports (rank 2) corresponding to the new FD-OCC#2 and #3 in CDM group #1.

[0190] Figure 19D shows an example of constraint D-2. In this example, UE#0 is directed to two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #0, and two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #1 (rank 4). These DMRS ports may be multiplexed with DMRS ports of another UE of rank 1. For example, UE#1 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#2 in CDM group #0. For example, UE#2 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#3 in CDM group #0. For example, UE#3 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#2 in CDM group #1. For example, UE#4 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#3 in CDM group #1.

[0191] Cases 1-5 For rank 5 (where 5 DMRS ports are specified), MU-MIMO may be subject to one of the following constraints:

[0192] [Constraint A] There are no restrictions.

[0193] [Constraint B] The maximum number of UE / DMRS ports that are multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2, 3}.

[0194] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. This constraint applies only if there are no available CDM groups for DMRS (data is FDM'd with DMRS); otherwise, another CDM group may be used for another UE.

[0195] [Constraint D] The constraint depends on the rank of another UE. That constraint may be either constraint D-1 or D-2 below. [[Constraint D-1]] Only option 1 is allowed, and option 2 is not allowed. Further constraints are possible. Constraint D-1 may be any of the following constraints D-1-1, D-1-2, or D-1-3. [[Constraint D-1-1]] Only option 1-1 below is allowed. [[Constraint D-1-2]] Only options 1-2 below are permitted. [[Constraint D-1-3]] Both options 1-1 and 1-2 below are permitted. [[Constraint D-2]] Only option 2 is allowed, and option 1 is not allowed.

[0196] [[Option 1]] The remaining DMRS ports are used for another UE of a rank greater than 1. [[Option 1-1]] The remaining DMRS ports are used for another Rank 2 UE. [[Option 1-2]] The remaining DMRS ports are used for another UE of rank 3. [[Option 2]] The remaining DMRS ports are used for another Rank 1 UE.

[0197] Figure 20A shows an example of constraint C. In this example, UE#0 is assigned four DMRS ports corresponding to new FD-OCC#0 to #3 in CDM group#0, and one DMRS port (rank 5) corresponding to new FD-OCC#0 in CDM group#1. Multiplexing of this DMRS port with orthogonal DMRS ports of other UEs may not be permitted.

[0198] Figure 20B shows an example of constraint D-1-1. In this example, UE#0 is directed to four DMRS ports corresponding to the new FD-OCC#0 to #3 in CDM group #0, and one DMRS port (rank 5) corresponding to the new FD-OCC#0 in CDM group #1. Another UE's DMRS port of rank 2 may be multiplexed to this DMRS port. For example, UE#1 may be directed to two DMRS ports (rank 2) corresponding to the new FD-OCC#2 and #3 in CDM group #1.

[0199] Figure 20C shows another example of constraint D-1-2. In this example, UE#0 is directed to four DMRS ports corresponding to the new FD-OCC#0 to #3 in CDM group #0, and one DMRS port (rank 5) corresponding to the new FD-OCC#0 in CDM group #1. This DMRS port may be multiplexed with DMRS ports of another UE of rank 3. For example, UE#1 may be directed to three DMRS ports (rank 3) corresponding to the new FD-OCC#1, #2, and #3 in CDM group #1.

[0200] Figure 20D shows an example of constraint D-2. In this example, UE#0 is directed to four DMRS ports corresponding to the new FD-OCC#0 to #3 in CDM group #0, and one DMRS port (rank 5) corresponding to the new FD-OCC#0 in CDM group #1. Another DMRS port of a different UE with rank 1 may be multiplexed to this DMRS port. For example, UE#1 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#1 in CDM group #1. For example, UE#2 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#2 in CDM group #1. For example, UE#3 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#3 in CDM group #1.

[0201] Figure 21A shows the first example of constraint D-1. In this example, DMRS configuration type 2 is set, and UE#0 is directed to four DMRS ports corresponding to the new FD-OCC#0 to #3 in CDM group #0, and one DMRS port (rank 5) corresponding to the new FD-OCC#0 in CDM group #1. DMRS ports of other UEs with ranks greater than 1 may be multiplexed to this DMRS port. For example, UE#1 may be directed to one DMRS port corresponding to the new FD-OCC#3 in CDM group #1, and four DMRS ports (rank 5) corresponding to the new FD-OCC#0 to #3 in CDM group #2. For example, UE#1 may not be directed to three DMRS ports corresponding to the new FD-OCC#1 to #3 in CDM group #1, and three DMRS ports (rank 6) corresponding to the new FD-OCC#0 to #2 in CDM group #2.

[0202] Figure 21B shows a second example of constraint D-1. In this example, DMRS configuration type 2 is set, and UE#0 is directed to four DMRS ports corresponding to the new FD-OCC#0 to #3 in CDM group #0, and one DMRS port corresponding to the new FD-OCC#0 in CDM group #1 (rank 5). DMRS ports of other UEs with ranks greater than 1 may be multiplexed to this DMRS port. For example, UE#1 may be directed to two DMRS ports corresponding to the new FD-OCC#2 and #3 in CDM group #1, and four DMRS ports corresponding to the new FD-OCC#0 to #3 in CDM group #2 (rank 6). For example, UE#1 may not be directed to three DMRS ports corresponding to the new FD-OCC#1 to #3 in CDM group #1, and three DMRS ports corresponding to the new FD-OCC#0 to #2 in CDM group #2 (rank 6).

[0203] Figure 21C shows a third example of constraint D-1. In this example, DMRS configuration type 2 is set, and UE#0 is directed to four DMRS ports corresponding to the new FD-OCC#0 through #3 in CDM group #0, and one DMRS port (rank 5) corresponding to the new FD-OCC#0 in CDM group #1. This DMRS port may be multiplexed with DMRS ports of other UEs of a rank greater than 1. For example, UE#1 may be directed to three DMRS ports corresponding to the new FD-OCC#1, #2, and #3 in CDM group #1, and four DMRS ports (rank 7) corresponding to the new FD-OCC#0 through #3 in CDM group #2.

[0204] Cases 1-6 For rank 6 (where 6 DMRS ports are specified), MU-MIMO may be subject to one of the following constraints:

[0205] [Constraint A] There are no restrictions.

[0206] [Constraint B] The maximum number of UE / DMRS ports that are multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2, 3}.

[0207] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. This constraint applies only if there are no available CDM groups for DMRS (data is FDM'd with DMRS); otherwise, another CDM group may be used for another UE.

[0208] [Constraint D] The constraint depends on the rank of another UE. That constraint may be either constraint D-1 or D-2 below. [[Constraint D-1]] Only option 1 is allowed, and option 2 is not allowed. Further constraints are possible. Constraint D-1 may be any of the following constraints D-1-1, D-1-2, or D-1-3. [[Constraint D-1-1]] Only option 1-1 below is allowed. [[Constraint D-1-2]] Only options 1-2 below are permitted. [[Constraint D-1-3]] Both options 1-1 and 1-2 below are permitted. [[Constraint D-2]] Only option 2 is allowed, and option 1 is not allowed.

[0209] [[Option 1]] The remaining DMRS ports are used for another UE of a rank greater than 1. [[Option 1-1]] The remaining DMRS ports are used for another Rank 2 UE. [[Option 1-2]] For another UE with a rank greater than 2, the remaining DMRS ports are used. [[Option 2]] The remaining DMRS ports are used for another Rank 1 UE.

[0210] Figure 22A shows an example of constraint C. In this example, UE#0 is assigned four DMRS ports corresponding to new FD-OCC#0 to #3 in CDM group #0, and two DMRS ports corresponding to new FD-OCC#0 and #1 in CDM group #1 (rank 6). Multiplexing of orthogonal DMRS ports of another UE to these DMRS ports is not permitted.

[0211] Figure 22B shows an example of constraint D-1-1. In this example, UE#0 is directed to four DMRS ports corresponding to the new FD-OCCs #0 to #3 in CDM group #0, and two DMRS ports (rank 6) corresponding to the new FD-OCCs #0 and #1 in CDM group #1. These DMRS ports may be multiplexed with DMRS ports of another UE of rank 2. For example, UE#1 may be directed to two DMRS ports (rank 2) corresponding to the new FD-OCCs #2 and #3 in CDM group #1.

[0212] Figure 22C shows an example of constraint D-1-2. In this example, DMRS configuration type 2 is set, and UE#0 is directed to four DMRS ports corresponding to the new FD-OCCs #0 to #3 in CDM group #0, and two DMRS ports (rank 6) corresponding to the new FD-OCCs #0 and #1 in CDM group #1. These DMRS ports may be multiplexed with DMRS ports of other UEs of a rank greater than 2. For example, UE#1 may be directed to two DMRS ports corresponding to the new FD-OCCs #2 and #3 in CDM group #1, and four DMRS ports (rank 6) corresponding to the new FD-OCCs #0 to #3 in CDM group #2.

[0213] Figure 22D shows an example of constraint D-2. In this example, UE#0 is directed to four DMRS ports corresponding to the new FD-OCC#0 to #3 in CDM group #0, and two DMRS ports (rank 6) corresponding to the new FD-OCC#0 and #1 in CDM group #1. These DMRS ports may be multiplexed with DMRS ports of another UE of rank 1. For example, UE#1 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#2 in CDM group #1. For example, UE#2 may be directed to one DMRS port (rank 1) corresponding to the new FD-OCC#3 in CDM group #1.

[0214] Figure 23A shows an example of a variation of constraint C. In this example, DMRS configuration type 2 is set, and UE#0 is instructed to have two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #0, two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #1, and two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #2 (rank 6). Multiplexing of orthogonal DMRS ports of another UE to these DMRS ports may not be permitted.

[0215] Figure 23B shows an example of a variation of constraint C. In this example, DMRS configuration type 2 is set, and UE#0 is instructed to have two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #0, two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #1, and two DMRS ports corresponding to the new FD-OCC#0 and #1 in CDM group #2 (rank 6). Multiplexing of DMRS ports from another UE may be permitted for these DMRS ports. In this case, constraint D may apply.

[0216] Cases 1-7 For rank 7 (where 7 DMRS ports are specified), MU-MIMO may be subject to one of the following constraints:

[0217] [Constraint A] There are no restrictions.

[0218] [Constraint B] The maximum number of UE / DMRS ports that are multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2, 3}.

[0219] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. This constraint applies only if there are no available CDM groups for DMRS (data is FDM'd with DMRS); otherwise, another CDM group may be used for another UE.

[0220] [Constraint D] The constraint depends on the rank of another UE. That constraint may be either constraint D-1 or D-2 below. [[Constraint D-1]] Only option 1 is allowed, and option 2 is not allowed. Further constraints may be present. [[Constraint D-2]] Only option 2 is allowed, and option 1 is not allowed.

[0221] [[Option 1]] The remaining DMRS ports are used for another UE of a rank greater than 1. [[Option 2]] The remaining DMRS ports are used for another Rank 1 UE.

[0222] FIG. 24A shows an example of constraint C. In this example, for UE #0, four DMRS ports corresponding to new FD-OCCs #0 to #3 in CDM group #0 and three DMRS ports corresponding to new FD-OCCs #0, #1, and #2 in CDM group #1 (rank 7) are indicated. It may not be allowed for the DMRS ports of another UE to be multiplexed with these DMRS ports.

[0223] FIG. 24B shows an example of constraint D-1. In this example, DMRS configuration type 2 is set, and for UE #0, four DMRS ports corresponding to new FD-OCCs #0 to #3 in CDM group #0 and three DMRS ports corresponding to new FD-OCCs #0, #1, and #2 in CDM group #1 (rank 7) are indicated. The DMRS ports of another UE with a rank larger than 1 may be multiplexed with these DMRS ports. For example, for UE #1, one DMRS port corresponding to new FD-OCC #3 in CDM group #1 and four DMRS ports corresponding to new FD-OCCs #0 to #3 in CDM group #2 (rank 5) may be indicated.

[0224] FIG. 24C shows an example of constraint D-2. In this example, for UE #0, four DMRS ports corresponding to new FD-OCCs #0 to #3 in CDM group #0 and three DMRS ports corresponding to new FD-OCCs #0, #1, and #2 in CDM group #1 (rank 7) are indicated. The DMRS ports of another UE with rank 1 may be multiplexed with these DMRS ports. For example, for UE #1, one DMRS port corresponding to new FD-OCC #3 in CDM group #1 (rank 1) may be indicated.

[0225] 《Case 1-8》 For rank 8 (the number of indicated DMRS ports is 8), MU-MIMO may follow any of the following several constraints.

[0226] [Constraint A] There is no constraint.

[0227] [Constraint B] The maximum number of UE / DMRS ports that are multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2, 3}.

[0228] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. This constraint applies only if there are no available CDM groups for DMRS (data is FDM'd with DMRS); otherwise, another CDM group may be used for another UE.

[0229] [Constraint D] The constraint depends on the rank of another UE. That constraint may be either constraint D-1 or D-2 below. [[Constraint D-1]] Only option 1 is allowed, and option 2 is not allowed. Further constraints may be present. [[Constraint D-2]] Only option 2 is allowed, and option 1 is not allowed.

[0230] [[Option 1]] The remaining DMRS ports are used for another UE of a rank greater than 1. [[Option 2]] The remaining DMRS ports are used for another Rank 1 UE.

[0231] Figure 25A shows an example of constraint C. In this example, UE#0 is assigned four DMRS ports corresponding to new FD-OCC#0 to #3 in CDM group#0, and four DMRS ports corresponding to new FD-OCC#0 to #3 in CDM group#1 (rank 8). Multiplexing of orthogonal DMRS ports of another UE to these DMRS ports is not permitted.

[0232] Figure 25B shows an example of a variation of constraint C. In this example, DMRS configuration type 2 is set, and UE#0 is instructed to have four DMRS ports corresponding to new FD-OCC#0 to #3 in CDM group #0, two DMRS ports corresponding to new FD-OCC#0 and #1 in CDM group #1, and two DMRS ports corresponding to new FD-OCC#0 and #1 in CDM group #2 (rank 8). Multiplexing of orthogonal DMRS ports of another UE is not permitted for these DMRS ports.

[0233] Figure 25C shows an example of a variation of constraint C. In this example, DMRS configuration type 2 is set, and UE#0 is directed to four DMRS ports corresponding to the new FD-OCCs #0 to #3 in CDM group #0, two DMRS ports corresponding to the new FD-OCCs #0 and #1 in CDM group #1, and two DMRS ports corresponding to the new FD-OCCs #0 and #1 in CDM group #2 (rank 8). These DMRS ports may be multiplexed with DMRS ports of another UE of rank 2. For example, UE#1 may be directed to two DMRS ports (rank 2) corresponding to the new FD-OCCs #2 and #3 in CDM group #1. For example, UE#2 may be directed to two DMRS ports (rank 2) corresponding to the new FD-OCCs #2 and #3 in CDM group #2.

[0234] The MU-MIMO scheduling constraints in each embodiment may be defined for PDSCH only. Alternatively, the MU-MIMO scheduling constraints in each embodiment may be defined for both PDSCH and PUSCH.

[0235] In cases 1-5 / 1-6 / 1-7 / 1-8, it may be assumed that single-symbol DMRS is used for SU-MIMO ranks 5 / 6 / 7 / 8 by a DMRS port with a new FD-OCC of length 4 / 6. In Rel. 15, double-symbol DMRS is used to support ranks 5 / 6 / 7 / 8. In each embodiment, if double-symbol DMRS is used, the MU-MIMO scheduling constraint may point to ranks 1 / 2 / 3 / 4. The total number of ranks may be doubled by the TD-OCC.

[0236] For 2CW (Rank 5 / 6 / 7 / 8), it is not necessary to allow all remaining DMRS ports within one CDM group or across multiple CDM groups to be directed to another UE.

[0237] Variations If two DMRS ports (rank 2) are directed to a given UE from two CDM groups, then one of the following constraints may apply:

[0238] If three DMRS ports (rank 3) from three CDM groups are directed to a given UE, then one of the following constraints may apply:

[0239] [Constraint A] There are no restrictions.

[0240] [Constraint B] The maximum number of UE / DMRS ports multiplexed within a single CDM group is limited. This maximum number may be specified in the specification, set by the RRC IE, or reported by the UE capability. The maximum number may be {0, 1, 2, 3}.

[0241] [Constraint C] All remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE. The UE may assume that all remaining orthogonal antenna ports are not associated with transmitting PDSCH to another UE.

[0242] [Constraint D] The constraint depends on the rank of another UE.

[0243] Figure 26A shows an example of Constraint C for rank 2. In this example, for UE#0, one DMRS port corresponding to the new FD-OCC#0 within CDM group #0 and one DMRS port corresponding to the new FD-OCC#0 within CDM group #1 (rank 2) are indicated. It may not be allowed for the orthogonal DMRS ports of another UE to be multiplexed with this DMRS port. This constraint may be applied to DMRS configuration type 1 or DMRS configuration type 2.

[0244] Figure 26B shows an example of Constraint C for rank 3. In this example, DMRS configuration type 2 is set, and for UE#0, one DMRS port corresponding to the new FD-OCC#0 within CDM group #0, one DMRS port corresponding to the new FD-OCC#0 within CDM group #1, and one DMRS port corresponding to the new FD-OCC#0 within CDM group #2 (rank 3) are indicated. It may not be allowed for the orthogonal DMRS ports of another UE to be multiplexed with this DMRS port.

[0245] When even-rank DMRS ports are indicated for a certain UE, it may be allowed for the even-rank DMRS ports of another UE to be multiplexed with that DMRS port. When even-rank DMRS ports are indicated for a certain UE, it may not be allowed for the odd-rank DMRS ports of another UE to be multiplexed with that DMRS port.

[0246] If an odd-ranked DMRS port is assigned to a UE, it may be permitted for another odd-ranked DMRS port from a different UE to be multiplexed to that DMRS port. However, if an odd-ranked DMRS port is assigned to a UE, it may not be permitted for another even-ranked DMRS port from a different UE to be multiplexed to that DMRS port.

[0247] According to this embodiment, the UE can appropriately perform MU-MIMO using the novel FD-OCC.

[0248] <Embodiment #2> This embodiment relates to MU-MIMO constraints for DMRS using novel FD-OCC and TD-OCC longer than 2 (whether a DMRS port of one UE is multiplexed to a DMRS port of another UE). This embodiment may also be applied to double-symbol DMRS.

[0249] There may be no restrictions on MU-MIMO (DMRS multiplexing using multiple different DMRS ports) spanning multiple different CDM groups.

[0250] MU-MIMO (DMRS multiplexing using multiple different DMRS ports) within or across a single CDM group may be subject to at least one of the following cases (new MU-MIMO scheduling constraints):

[0251] Case 2-1 If a UE is scheduled for 2CW (Rank 5 / 6 / 7 / 8), it may not be permissible for all remaining DMRS ports within one CDM group or across multiple CDM groups to be assigned to another UE.

[0252] Figure 27A shows an example of rank 5 in Case 2-1. In this example, UE#0 is assigned four DMRS ports within CDM group #0 corresponding to TD-OCC#0 and new FD-OCC#0 to #3, and one DMRS port corresponding to TD-OCC#1 and new FD-OCC#0 (rank 5). Multiplexing of orthogonal DMRS ports of other UEs to this DMRS port is not permitted.

[0253] Figure 27B shows an example of rank 6 in Case 2-1. In this example, UE#0 is assigned four DMRS ports within CDM group #0 corresponding to TD-OCC#0 and new FD-OCC#0 to #3, and two DMRS ports corresponding to TD-OCC#1 and new FD-OCC#0 and #1 (rank 6). Multiplexing of orthogonal DMRS ports of another UE to these DMRS ports is not permitted.

[0254] Figure 27C shows an example of rank 7 in Case 2-1. In this example, UE#0 is assigned four DMRS ports within CDM group #0 corresponding to TD-OCC#0 and new FD-OCC#0 to #3, and three DMRS ports corresponding to TD-OCC#1 and new FD-OCC#0, #1, and #2 (rank 7). Multiplexing of orthogonal DMRS ports of another UE to these DMRS ports is not permitted.

[0255] Figure 27D shows an example of rank 8 in Case 2-1. In this example, UE#0 is assigned four DMRS ports within CDM group #0 corresponding to TD-OCC#0 and new FD-OCC#0 to #3, and four DMRS ports corresponding to TD-OCC#1 and new FD-OCC#0 to #3 (rank 8). Multiplexing of orthogonal DMRS ports of another UE to these DMRS ports is not permitted.

[0256] Variations of Case 2-1 For a given UE's 2CW (rank 5 / 6 / 7 / 8), it may be permissible for the remaining DMRS ports, which are within one CDM group or span multiple CDM groups, to be assigned to another UE.

[0257] Figure 28A shows an example of rank 5 in Case 2-1. In this example, UE#0 is assigned four DMRS ports within CDM group #0 corresponding to TD-OCC#0 and the new FD-OCC#0 through #3, and one DMRS port corresponding to TD-OCC#1 and the new FD-OCC#0 (rank 5). The remaining DMRS ports within CDM group #0 may be assigned to other UEs.

[0258] Figure 28B shows an example of rank 6 in Case 2-1. In this example, UE#0 is assigned four DMRS ports within CDM group #0 corresponding to TD-OCC#0 and the new FD-OCC#0 through #3, and two DMRS ports corresponding to TD-OCC#1 and the new FD-OCC#0 and #1 (rank 6). The remaining DMRS ports within CDM group #0 may be assigned to other UEs.

[0259] Figure 28C shows an example of rank 7 in Case 2-1. In this example, UE#0 is assigned four DMRS ports within CDM group #0 corresponding to TD-OCC#0 and the new FD-OCC#0 through #3, and three DMRS ports corresponding to TD-OCC#1 and the new FD-OCC#0, #1, and #2 (rank 7). The remaining DMRS ports within CDM group #0 may be assigned to other UEs.

[0260] Case 2-2 When a certain UE is scheduled for 1CW, and several DMRS ports are associated with TD-OCC#1, then 3 / 2 / 1 / 0 DMRS ports remain in that CDM group. The scheduling constraints for these 3 / 2 / 1 / 0 DMRS ports may follow Case 1-1 / 1-2 / 1-3 / 1-4 (ranks 1 / 2 / 3 / 4) of Embodiment #1.

[0261] Figure 29A shows the first example of Case 2-2. In this example, UE#0 is assigned three DMRS ports within CDM group #0 corresponding to TD-OCC#0 and the new FD-OCC#0, #1, and #2, and one DMRS port corresponding to TD-OCC#1 and the new FD-OCC#0 (rank 4). The remaining DMRS ports within CDM group #0 may follow Cases 1-1 / 1-2 / 1-3 / 1-4 of Embodiment #1 (ranks 1 / 2 / 3 / 4).

[0262] Figure 29B shows a second example of Case 2-2. In this example, UE#0 is assigned one DMRS port within CDM group #0 corresponding to TD-OCC#0 and the new FD-OCC#0, and three DMRS ports (rank 4) corresponding to TD-OCC#1 and the new FD-OCC#0, #1, and #2. The remaining DMRS ports within CDM group #0 may follow Cases 1-1 / 1-2 / 1-3 / 1-4 of Embodiment #1 (ranks 1 / 2 / 3 / 4).

[0263] Figure 29C shows a third example of Case 2-2. In this example, UE#0 is assigned two DMRS ports within CDM group #0 corresponding to TD-OCC#0 and the new FD-OCC#0,#1, and two DMRS ports corresponding to TD-OCC#1 and the new FD-OCC#0,#1 (rank 4). The remaining DMRS ports within CDM group #0 may follow Cases 1-1 / 1-2 / 1-3 / 1-4 of Embodiment #1 (ranks 1 / 2 / 3 / 4).

[0264] Figure 29D shows a fourth example of Case 2-2. In this example, UE#0 is assigned two DMRS ports within CDM group #0 corresponding to TD-OCC#0 and new FD-OCC#2,#3, and two DMRS ports corresponding to TD-OCC#1 and new FD-OCC#2,#3 (rank 4). The remaining DMRS ports within CDM group #0 may follow Cases 1-1 / 1-2 / 1-3 / 1-4 of Embodiment #1 (ranks 1 / 2 / 3 / 4).

[0265] According to this embodiment, the UE can appropriately perform MU-MIMO using TD-OCC and novel FD-OCC.

[0266] <Embodiment #3> This embodiment relates to existing MU-MIMO scheduling constraints.

[0267] The existing MU-MIMO scheduling constraint may apply only to DMRS ports associated with FD-OCCs of length 2 (existing FD-OCCs). The new MU-MIMO scheduling constraints of Embodiment #1 / #2 may apply to DMRS ports associated with FD-OCCs longer than 2 (new FD-OCCs). In the new MU-MIMO scheduling constraints, the constrained antenna port indices may differ from {2,9,10,11,30} / {2,10,23} in the existing MU-MIMO scheduling constraints.

[0268] According to this embodiment, the UE can perform MU-MIMO appropriately whether an existing FD-OCC or a new FD-OCC is used.

[0269] <Supplement> [Notification of information to UE] In the embodiments described above, notification of any information from a Network (NW) (e.g., a Base Station (BS)) to a UE (in other words, reception of any information from a BS at the UE) may be performed using physical layer signaling (e.g., DCI), higher layer signaling (e.g., RRC signaling, MAC CE), specific signals / channels (e.g., PDCCH, PDSCH, reference signal), or a combination thereof.

[0270] If the above notification is made by a MAC CE, the MAC CE may be identified by the inclusion of a new Logical Channel ID (LCID) not defined in existing standards in the MAC subheader.

[0271] If the above notification is made by a DCI, the notification may be made by a specific field of the DCI, a Radio Network Temporary Identifier (RNTI) used to scramble the Cyclic Redundancy Check (CRC) bits assigned to the DCI, or the format of the DCI.

[0272] Furthermore, the notification of any information to the UE in the above-described embodiment may be periodic, semi-persistent, or aperiodic.

[0273] [Notification of information from UE] In the embodiments described above, notification of any information from the UE (to the NW) (in other words, transmission / reporting 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), specific signals / channels (e.g., PUCCH, PUSCH, PRACH, reference signals), or a combination thereof.

[0274] If the above notification is made by a MAC CE, the MAC CE may be identified by the inclusion of a new LCID, not specified in existing standards, in the MAC subheader.

[0275] If the above notice is issued by the UCI, the notice may be sent using PUCCH or PUSCH.

[0276] Furthermore, the notification of any information from the UE in the above-described embodiments may be periodic, semi-persistent, or aperiodic.

[0277] [Regarding the application of each embodiment] At least one of the embodiments described above may be applied if certain conditions are met. These conditions may be specified in a standard or notified to the UE / BS using upper-layer signaling / physical layer signaling.

[0278] At least one of the embodiments described above may apply only to a UE that has reported or supports a particular UE capability.

[0279] The specific UE capability may represent at least one of the following: • To support specific processing / operation / control / information for at least one of the above embodiments. • To support a greater number of DMRS ports for PDSCH / PUSCH than the existing specifications. - To support a greater number of DMRS ports than existing specifications for PDSCH / PUSCH DMRS using TD-OCC / FD-OCC / FDM. • Supports FD OCCs with a length of 4 / 6 inches. In one or more cases of Embodiment #1 / #2 (e.g., cases where the rank is greater than 1), is MU-MIMO possible within a single CDM group? • The maximum number of UE / DMRS ports that are MU-MIMO multiplexed within a single CDM group. • In MU-MIMO, one or more cases from Embodiment #1 / #2 are permitted (supported). For example, rank 1 only. For example, a list of one or more permitted DMRS ports.

[0280] Furthermore, the above-mentioned specific UE capabilities may be capabilities that apply across all frequencies (commonly regardless of frequency), capabilities per frequency (e.g., one or a combination thereof, such as cell, band, band combination, BWP, component carrier, etc.), capabilities per frequency range (e.g., Frequency Range 1 (FR1), FR2, FR3, FR4, FR5, FR2-1, FR2-2), capabilities per subcarrier spacing (SCS), or capabilities per feature set (FS) or feature set per component-carrier (FSPC).

[0281] Furthermore, the specific UE capabilities described above may be capabilities that apply across all duplexing schemes (common to all duplexing schemes), or they may be capabilities specific to each duplexing scheme (e.g., Time Division Duplex (TDD), Frequency Division Duplex (FDD)).

[0282] Furthermore, at least one of the embodiments described above may be applied when the UE is configured / activated / triggered by upper layer signaling / physical layer signaling to perform certain information (or the actions of the embodiments described above) related to the embodiments described above. For example, such certain information may be information indicating the activation of the functionality of each embodiment, or arbitrary RRC parameters for a particular release (e.g., Rel. 18 / 19).

[0283] If the UE does not support at least one of the above-mentioned specific UE capabilities or does not have the above-mentioned specific information configured, the behavior of, for example, Rel.15 / 16 may be applied.

[0284] (Note A) The following invention is added with respect to one embodiment of this disclosure. [Note 1] A receiving unit that receives instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for a demodulated reference signal (DMRS) to which a frequency domain orthogonal cover code (FD-OCC) longer than 2 is applied, A terminal having a control unit that determines, based on the instruction, whether to assume that the remaining antenna ports of one or more antenna ports within the one or more CDM groups are allocated for transmitting downlink sharing channels to another terminal. [Note 2] If the instruction indicates a specific number of antenna ports, the control unit assumes that, within the one or more CDM groups, the remaining antenna ports of the one or more antenna ports are allocated for transmitting downlink sharing channels to another terminal, as described in Appendix 1. [Note 3] If the instruction indicates a specific number of antenna ports, the control unit assumes that, within the one or more CDM groups, the remaining antenna ports of the one or more antenna ports are not allocated for transmitting downlink sharing channels to another terminal, as described in Appendix 1 or Appendix 2. [Note 4] If the instruction indicates a specific number of antenna ports, the control unit determines whether to assume that the remaining antenna ports are allocated for transmitting downlink sharing channels to another terminal, based on at least one of the following: the maximum number of antenna ports allocated within one of the one or more CDM groups, the maximum number of terminals multiplexed within one CDM group, and the number of antenna ports allocated to another terminal, as described in any of Appendix 1 to Appendix 3.

[0285] (Note B) The following invention is added with respect to one embodiment of this disclosure. [Note 1] A receiving unit that receives instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for a demodulated reference signal (DMRS) to which a frequency domain orthogonal cover code (FD-OCC) longer than 2 is applied, A terminal having a control unit that determines, based on the instruction, whether to assume that the remaining antenna ports of one or more antenna ports within one or more CDM groups are allocated for transmission of uplink shared channels from another terminal. [Note 2] If the instruction indicates a specific number of antenna ports, the control unit assumes that, within the one or more CDM groups, the remaining antenna ports of the one or more antenna ports are allocated for transmission of uplink shared channels from another terminal, as described in Appendix 1. [Note 3] If the instruction indicates a specific number of antenna ports, the control unit assumes that, within the one or more CDM groups, the remaining antenna ports of the one or more antenna ports are not allocated for transmission of uplink shared channels from another terminal, as described in Appendix 1 or Appendix 2. [Note 4] If the instruction indicates a specific number of antenna ports, the control unit determines whether to assume that the remaining antenna ports are allocated for transmission of uplink shared channels from another terminal, based on at least one of the following: the maximum number of antenna ports allocated within one of the one or more CDM groups, the maximum number of terminals multiplexed within one CDM group, and the number of antenna ports allocated to another terminal, as described in any of Appendix 1 to Appendix 3.

[0286] (Wireless communication system) The configuration of a wireless communication system according to one embodiment of this disclosure will be described below. In this wireless communication system, communication is performed using any or a combination thereof of the wireless communication methods according to the above embodiments of this disclosure.

[0287] Figure 30 shows an example of a schematic configuration of a wireless communication system according to one embodiment. The wireless communication system 1 (which may also be simply called system 1) may be a system that realizes communication using Long Term Evolution (LTE), 5th generation mobile communication system New Radio (5G NR), etc., as specified by the Third Generation Partnership Project (3GPP).

[0288] Furthermore, the wireless communication system 1 may 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)), and so on.

[0289] In EN-DC, the LTE (E-UTRA) base station (eNB) is the Master Node (MN), and the NR base station (gNB) is the 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.

[0290] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity where both MN and SN are NR base stations (gNB) (NR-NR Dual Connectivity (NN-DC))).

[0291] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with relatively wide coverage, and base stations 12 (12a-12c) located within the macrocell C1 that form a small cell C2 that is narrower than the macrocell C1. User terminals 20 may be located within at least one cell. The arrangement and number of each cell and user terminal 20 are not limited to the configuration shown in the figure. Hereinafter, when base stations 11 and 12 are not distinguished, they will be collectively referred to as base station 10.

[0292] 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 (CC) and Dual Connectivity (DC).

[0293] Each CC may be included in at least one of the first frequency band (Frequency Range 1 (FR1)) and the second frequency band (Frequency Range 2 (FR2)). A macrocell C1 may be included in FR1, and a 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 above 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 fall in a frequency band higher than FR2.

[0294] Furthermore, the user terminal 20 may communicate using at least one of the following methods at each CC: Time Division Duplex (TDD) and Frequency Division Duplex (FDD).

[0295] Multiple base stations 10 may be connected by wire (e.g., optical fiber compliant with Common Public Radio Interface (CPRI), X2 interface, etc.) or wireless (e.g., NR communication). For example, if NR communication is used as a backhaul between base stations 11 and 12, base station 11, which is the upstream station, may be called an Integrated Access Backhaul (IAB) donor, and base station 12, which is the relay station, may be called an IAB node.

[0296] Base station 10 may be connected to the core network 30 via other base stations 10 or directly. The core network 30 may include at least one of the following: Evolved Packet Core (EPC), 5G Core Network (5GCN), Next Generation Core (NGC), etc.

[0297] The core network 30 may include network functions (NF) such as User Plane Function (UPF), Access and Mobility Management Function (AMF), Session Management Function (SMF), Unified Data Management (UDM), Application Function (AF), Data Network (DN), Location Management Function (LMF), and Operation, Administration and Maintenance (Management) (OAM). Multiple functions may be provided by a single network node. Furthermore, communication with an external network (e.g., the Internet) may occur via the DN.

[0298] The user terminal 20 may be a terminal that supports at least one of the following communication methods: LTE, LTE-A, 5G, etc.

[0299] In the wireless communication system 1, an orthogonal frequency division multiplexing (OFDM)-based wireless access scheme may be used. 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), etc., may be used in at least one of the downlink (DL) and uplink (UL).

[0300] The wireless access method may also be called a waveform. In wireless communication system 1, other wireless access methods (for example, other single-carrier transmission methods, other multi-carrier transmission methods) may be used for the UL and DL wireless access methods.

[0301] In the wireless communication system 1, a Physical Downlink Shared Channel (PDSCH), a Broadcast Channel (PBCH), or a Physical Downlink Control Channel (PDCCH) may be used as the downlink channel, shared by each user terminal 20.

[0302] Furthermore, in the wireless communication system 1, the uplink channel may include a Physical Uplink Shared Channel (PUSCH), a Physical Uplink Control Channel (PUCCH), a Physical Random Access Channel (PRACH), etc., shared by each user terminal 20.

[0303] User data, higher-layer control information, and System Information Blocks (SIBs) are transmitted via PDSCH. User data and higher-layer control information may also be transmitted via PUSCH. Furthermore, Master Information Blocks (MIBs) may be transmitted via PBCH.

[0304] Lower-layer control information may be transmitted by PDCCH. The lower-layer control information may include, for example, Downlink Control Information (DCI) which includes scheduling information for at least one of PDSCH and PUSCH.

[0305] Furthermore, the DCI that schedules PDSCH may be called a DL assignment or DL ​​DCI, and the DCI that schedules PUSCH may be called a UL grant or UL DCI. Furthermore, PDSCH may be interpreted as DL data, and PUSCH may be interpreted as UL data.

[0306] PDCCH detection may utilize a Control Resource Set (CORESET) and a search space. A CORESET corresponds to the resources used to search for DCIs. A search space corresponds to the search area and search method for PDCCH candidates. A single CORESET may be associated with one or more search spaces. The UE may monitor CORESETs associated with a particular search space based on the search space configuration.

[0307] A single search space may correspond to one or more PDCCH candidates corresponding to aggregation levels. One or more search spaces may be referred to as a search space set. In this disclosure, "search space," "search space set," "search space configuration," "search space set configuration," "CORESET," and "CORESET configuration" may be interpreted interchangeably.

[0308] PUCCH may transmit uplink control information (UCI) which includes at least one of the following: channel state information (CSI), delivery acknowledgment (e.g., Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). PRACH may transmit a random access preamble for establishing a connection with the cell.

[0309] In this disclosure, downlinks, uplinks, etc., may be expressed without the prefix "link." Also, the prefix "physical" may be omitted when describing various channels.

[0310] 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 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.

[0311] 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 SS (PSS, SSS) and PBCH (and DMRS for PBCH) may be called an SS / PBCH block, SS Block (SSB), etc. SS, SSB, etc., may also be called reference signals.

[0312] Furthermore, in the wireless communication system 1, the Uplink Reference Signal (UL-RS) may transmit the Sounding Reference Signal (SRS), Demodulation Reference Signal (DMRS), etc. The DMRS may also be called the User-Specific Reference Signal (UE-specific Reference Signal).

[0313] (base station) Figure 31 shows an example of the configuration of a base station according to one 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 one or more of the control unit 110, transceiver unit 120, transceiver antenna 130, and transmission line interface 140 may be provided.

[0314] In this example, the functional blocks of the characteristic parts of this 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 part described below may be omitted.

[0315] The control unit 110 controls the entire base station 10. The control unit 110 can be composed of a controller, control circuit, etc., as described based on common understanding in the art relating to this disclosure.

[0316] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may also control transmission and reception, measurement, etc., using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140. The control unit 110 may generate data to be transmitted as signals, control information, sequences, etc., and transfer them to the transceiver unit 120. The control unit 110 may also perform call processing of communication channels (setting, releasing, etc.), status management of the base station 10, management of radio resources, etc.

[0317] The transmitting / receiving 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 transmitting / receiving unit 120 can be composed of a transmitter / receiver, RF circuit, baseband circuit, filter, phase shifter, measurement circuit, transmitting / receiving circuit, etc., as described based on common understanding in the art relating to this disclosure.

[0318] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or it may be composed of a transmitting unit and a receiving unit. The transmitting unit may consist of a transmitting processing unit 1211 and an RF unit 122. The receiving unit may consist of a receiving processing unit 1212, an RF unit 122 and a measuring unit 123.

[0319] The transmitting and receiving antenna 130 can be composed of an antenna described based on common understanding in the art relating to this disclosure, such as an array antenna.

[0320] The transmitting / receiving unit 120 may transmit the downlink channel, synchronization signal, downlink reference signal, etc. The transmitting / receiving unit 120 may also receive the uplink channel, uplink reference signal, etc.

[0321] The transmitting / receiving unit 120 may form at least one of the transmitting beam and the receiving beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0322] The transmitting / receiving unit 120 (transmission processing unit 1211) may perform processing on data and control information acquired from the control unit 110, for example, at the Packet Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer (e.g., RLC retransmission control), the Medium Access Control (MAC) layer (e.g., HARQ retransmission control), etc., to generate a bit sequence to be transmitted.

[0323] The transmitting / receiving unit 120 (transmission processing unit 1211) may perform transmission processing on the bit sequence to be transmitted, 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, and output a baseband signal.

[0324] The transmitting / receiving unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc., of the baseband signal to the radio frequency band and transmit the signal in the radio frequency band via the transmitting / receiving antenna 130.

[0325] On the other hand, the transmitting / receiving unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc., on the radio frequency band signal received by the transmitting / receiving antenna 130.

[0326] The transmitting / receiving unit 120 (receiving processing unit 1212) may apply reception processing to the acquired baseband signal, such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing, to acquire user data, etc.

[0327] The transmitting / receiving unit 120 (measurement unit 123) may perform measurements related to 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 also measure received power (e.g., Reference Signal Received Power (RSRP)), reception 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.

[0328] The transmission path interface 140 may send and receive signals (backhaul signaling) with devices included in the core network 30 (e.g., network nodes providing 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.

[0329] In this disclosure, the transmitting and receiving units of the base station 10 may consist of at least one of a transmitting / receiving unit 120, a transmitting / receiving antenna 130, and a transmission path interface 140.

[0330] The transmitting / receiving unit 120 may transmit to the terminal instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for demodulated reference signals (DMRS) to which frequency domain orthogonal cover codes (FD-OCC) longer than 2 are applied. The control unit 110 may determine whether to assume that the remaining antenna ports of the one or more antenna ports in the one or more CDM groups are allocated for transmitting downlink shared channels to another terminal.

[0331] The transmitting / receiving unit 120 may transmit to the terminal instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for demodulated reference signals (DMRS) to which frequency domain orthogonal cover codes (FD-OCC) longer than 2 are applied. The control unit 110 may determine whether to assume that the remaining antenna ports of the one or more antenna ports in the one or more CDM groups are allocated for transmission of uplink shared channels from another terminal.

[0332] (User terminal) Figure 32 shows an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transmitting / receiving unit 220, and a transmitting / receiving antenna 230. Note that one or more of the control unit 210, the transmitting / receiving unit 220, and the transmitting / receiving antenna 230 may be provided.

[0333] In this example, the functional blocks of the characteristic parts of this 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 part described below may be omitted.

[0334] The control unit 210 controls the entire user terminal 20. The control unit 210 can be composed of a controller, control circuit, etc., as described based on common understanding in the technical field related to this disclosure.

[0335] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may also control transmission and reception, measurement, etc., using the transmitting / receiving unit 220 and the transmitting / receiving antenna 230. The control unit 210 may generate data to be transmitted as signals, control information, sequences, etc., and transfer them to the transmitting / receiving unit 220.

[0336] The transmitting / receiving 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 transmitting / receiving unit 220 can be composed of a transmitter / receiver, RF circuit, baseband circuit, filter, phase shifter, measurement circuit, transmitting / receiving circuit, etc., as described based on common understanding in the art relating to this disclosure.

[0337] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or it may be composed of a transmitting unit and a receiving unit. The transmitting unit may consist of a transmitting processing unit 2211 and an RF unit 222. The receiving unit may consist of a receiving processing unit 2212, an RF unit 222 and a measuring unit 223.

[0338] The transmitting and receiving antenna 230 can be composed of an antenna described based on common understanding in the art relating to this disclosure, such as an array antenna.

[0339] The transmitting / receiving unit 220 may receive the downlink channel, synchronization signal, downlink reference signal, etc. The transmitting / receiving unit 220 may also transmit the uplink channel, uplink reference signal, etc.

[0340] The transmitting / receiving unit 220 may form at least one of the transmitting beam and the receiving beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0341] The transmitting / receiving 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 and control information acquired from the control unit 210, etc., to generate a bit sequence to be transmitted.

[0342] The transmitting / receiving unit 220 (transmission processing unit 2211) may perform transmission processing on the bit sequence to be transmitted, 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, and output a baseband signal.

[0343] Whether or not to apply DFT processing may be based on the transform precoding settings. The transmitting / receiving unit 220 (transmission processing unit 2211) may perform DFT processing as part of the transmission process to transmit a channel (for example, PUSCH) using a DFT-s-OFDM waveform if transform precoding is enabled for that channel, or it may not perform DFT processing as part of the transmission process if transform precoding is not enabled for that channel.

[0344] The transmitting / receiving unit 220 (RF unit 222) may perform modulation, filtering, amplification, etc., of the baseband signal to the radio frequency band and transmit the signal in the radio frequency band via the transmitting / receiving antenna 230.

[0345] On the other hand, the transmitting / receiving unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc., on the radio frequency band signal received by the transmitting / receiving antenna 230.

[0346] The transmitting / receiving unit 220 (receiving processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal to acquire user data, etc.

[0347] The transmitting / receiving unit 220 (measuring unit 223) may perform measurements related to the received signal. For example, the measuring unit 223 may perform RRM measurement, CSI measurement, etc., based on the received signal. The measuring unit 223 may also 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.

[0348] In this disclosure, the transmitting and receiving units of the user terminal 20 may consist of at least one of a transmitting / receiving unit 220 and a transmitting / receiving antenna 230.

[0349] The transmitting / receiving unit 220 may receive instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for demodulated reference signals (DMRS) to which frequency domain orthogonal cover codes (FD-OCC) longer than 2 are applied. The control unit 210 may determine, based on the instructions, whether to assume that the remaining antenna ports of the one or more antenna ports in the one or more CDM groups are allocated for transmitting downlink shared channels to another terminal.

[0350] If the instruction indicates a specific number of antenna ports, the control unit 210 may assume that, within the one or more CDM groups, the remaining antenna ports of the one or more antenna ports are allocated for transmitting downlink sharing channels to other terminals.

[0351] If the instruction indicates a specific number of antenna ports, the control unit 210 may assume that, within the one or more CDM groups, the remaining antenna ports of the one or more antenna ports are not allocated for transmitting downlink sharing channels to other terminals.

[0352] If the instruction indicates a specific number of antenna ports, the control unit 210 may determine whether to assume that the remaining antenna ports are allocated for transmitting downlink shared channels to other terminals, based on at least one of the following: the maximum number of antenna ports allocated within one of the one or more CDM groups, the maximum number of terminals multiplexed within one CDM group, and the number of antenna ports allocated to another terminal.

[0353] The transmitting / receiving unit 220 may receive instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for demodulated reference signals (DMRS) to which frequency domain orthogonal cover codes (FD-OCC) longer than 2 are applied. The control unit 210 may determine, based on the instructions, whether to assume that the remaining antenna ports of the one or more antenna ports in the one or more CDM groups are allocated for transmission of uplink shared channels from another terminal.

[0354] If the instruction indicates a specific number of antenna ports, the control unit may assume that, within the one or more CDM groups, the remaining antenna ports of the one or more antenna ports are allocated for transmission of uplink shared channels from another terminal.

[0355] If the instruction indicates a specific number of antenna ports, the control unit may assume that, within the one or more CDM groups, the remaining antenna ports of one or more antenna ports are not allocated for transmission of uplink shared channels from another terminal.

[0356] If the instruction indicates a specific number of antenna ports, the control unit may determine whether to assume that the remaining antenna ports are allocated for transmission of uplink shared channels from another terminal, based on at least one of the following: the maximum number of antenna ports allocated within one of the one or more CDM groups, the maximum number of terminals multiplexed within one CDM group, and the number of antenna ports allocated to another terminal.

[0357] (Hardware configuration) The block diagrams used in the description of the above embodiments show functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or it may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may also be realized by combining the above one device or the above multiple devices with software.

[0358] Here, functions include, but are not limited to, judgment, decision, determination, calculation, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating (mapping), and assigning. For example, a functional block (configuration part) that enables transmission may be called a transmitting unit or transmitter. In all cases, as mentioned above, the method of implementation is not particularly limited.

[0359] For example, a base station, user terminal, etc. in one embodiment of the present disclosure may function as a computer that processes the wireless communication method of the present disclosure. Figure 33 is a diagram showing an example of the hardware configuration of a base station and user terminal according to one embodiment. The base station 10 and user terminal 20 described above may be physically configured as a computer device including a processor 1001, memory 1002, storage 1003, communication device 1004, input device 1005, output device 1006, bus 1007, etc.

[0360] In this disclosure, terms such as apparatus, circuit, device, section, and unit are interchangeable. The hardware configuration of the base station 10 and the user terminal 20 may include one or more of the devices shown in the figure, or it may be configured to omit some of the devices.

[0361] For example, although only one processor 1001 is shown in the diagram, there may be multiple processors. Furthermore, processing may be performed by one processor, or by two or more processors simultaneously, sequentially, or by other means. Note that processor 1001 may be implemented using one or more chips.

[0362] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading predetermined software (programs) onto hardware such as the processor 1001 and memory 1002, which allows the processor 1001 to perform calculations and control communication via the communication device 1004, or to control at least one of the reading and writing of data in the memory 1002 and storage 1003.

[0363] The processor 1001 controls the entire computer, for example, by running an operating system. The processor 1001 may be composed of a central processing unit (CPU) that includes interfaces with peripheral devices, control units, arithmetic units, registers, etc. For example, at least a part of the control unit 110 (210) and the transmitting / receiving unit 120 (220) described above may be implemented by the processor 1001.

[0364] Furthermore, the processor 1001 reads programs (program code), 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 accordingly. The program used is one that causes the computer to execute at least a part of the operations described in the above embodiment. 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 other functional blocks may be implemented similarly.

[0365] Memory 1002 is a computer-readable recording medium and may consist of at least one of the following: Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EPROM (EEPROM), Random Access Memory (RAM), or other suitable storage medium. Memory 1002 may also be called a register, cache, or main memory. Memory 1002 can store executable programs (program code), software modules, etc., for carrying out a wireless communication method according to one embodiment of this disclosure.

[0366] Storage 1003 is a computer-readable recording medium and may consist of at least one of the following: a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disk (Compact Disc ROM (CD-ROM)), a digital multipurpose disk, a Blu-ray disk), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, stick, key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be called an auxiliary storage device.

[0367] The communication device 1004 is hardware (transmitting / receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, communication module, etc. The communication device 1004 may be configured to include, for example, a high-frequency switch, duplexer, filter, frequency synthesizer, etc., in order to implement at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmitting / receiving unit 120 (220), transmitting / receiving antenna 130 (230), etc., may be implemented by the communication device 1004. The transmitting / receiving unit 120 (220) may be implemented with physically or logically separated implementations of a transmitting unit 120a (220a) and a receiving unit 120b (220b).

[0368] The input device 1005 is an input device that accepts input from an external source (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to an external source (e.g., a display, speaker, light-emitting diode (LED) lamp, etc.). The input device 1005 and the output device 1006 may be configured as an integrated unit (e.g., a touch panel).

[0369] Furthermore, each device, such as the processor 1001 and memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or different buses may be configured for each device.

[0370] 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), and a field programmable gate array (FPGA), and some or all of each functional block may be implemented using such hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0371] (modified version) In addition, terms used in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, channel, symbol, and signal (signal or signaling) may be used interchangeably. Also, a signal may be a message. A reference signal may be abbreviated as RS and may be called a pilot, pilot signal, etc., depending on the applicable standard. Also, a component carrier (CC) may be called a cell, frequency carrier, carrier frequency, etc.

[0372] A wireless frame may consist of one or more periods (frames) in the time domain. Each of these periods (frames) constituting a wireless frame may be called a subframe. Furthermore, a subframe may consist 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.

[0373] Here, the neuralelogy may be communication parameters applied to at least one of the transmission and reception of a signal or channel. The neuralelogy may be, for example, at least one of the following: subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, specific filtering processes performed by the transceiver in the frequency domain, or specific windowing processes performed by the transceiver in the time domain.

[0374] A slot may consist of one or more symbols in the time domain (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols or Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols). Alternatively, a slot may be a time unit based on neurology.

[0375] A slot may include multiple mini-slots. Each mini-slot may consist of one or more symbols in the time domain. Mini-slots may also be called sub-slots. Mini-slots may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a mini-slot may be called a PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a mini-slot may be called a PDSCH (PUSCH) mapping type B.

[0376] Wireless frames, subframes, slots, minislots, and symbols all represent units of time when transmitting a signal. Wireless frames, subframes, slots, minislots, and symbols may each be referred to by different names. Furthermore, the units of time such as frames, subframes, slots, minislots, and symbols in this disclosure may be interpreted as interchangeable.

[0377] For example, one subframe may be called TTI, multiple consecutive subframes may be called TTI, or one slot or one mini-slot may be called TTI. In other words, at least one of the subframe and TTI may be a subframe (1ms) in existing LTE, a period shorter than 1ms (e.g., 1-13 symbols), or a period longer than 1ms. Note that the unit representing TTI may be called a slot, mini-slot, etc., instead of a subframe.

[0378] Here, TTI refers to, for example, the smallest unit of time for scheduling in wireless communication. For example, in an LTE system, the base station schedules each user terminal to allocate wireless resources (such as the frequency bandwidth and transmission power available to each user terminal) in TTI units. However, the definition of TTI is not limited to this.

[0379] TTI may be a transmission time unit for channel-encoded data packets (transport blocks), code blocks, code words, etc., or it may be a processing unit for scheduling, link adaptation, etc. Given a TTI, the actual time interval (e.g., number of symbols) to which the transport block, code block, code word, etc. are mapped may be shorter than the given TTI.

[0380] Furthermore, if one slot or one mini-slot is referred to as TTI, then one or more TTIs (i.e., one or more slots or one or more mini-slots) may constitute the minimum time unit of scheduling. In addition, the number of slots (number of mini-slots) that constitute the minimum time unit of scheduling may be controlled.

[0381] A TTI with a time length of 1 ms may also be called a normal TTI (TTI in 3GPP Rel.8-12), a long TTI, a normal subframe, a long subframe, or a slot. A TTI shorter than a normal TTI may also be called a shortened TTI, a short TTI, a partial or fractional TTI, a shortened subframe, a short subframe, a mini slot, a sub slot, or a slot.

[0382] Furthermore, long TTIs (e.g., normal TTIs, subframes, etc.) may be interpreted as TTIs with a time length exceeding 1 ms, and short TTIs (e.g., shortened TTIs, etc.) may be interpreted as TTIs with a TTI length less than that of a long TTI but 1 ms or more.

[0383] A Resource Block (RB) is a resource allocation unit in the time domain and frequency domain, and in the frequency domain, it may contain one or more consecutive subcarriers. The number of subcarriers in an RB may be the same regardless of the neurology, for example, 12. The number of subcarriers in an RB may be determined based on the neurology.

[0384] Furthermore, an RB may contain one or more symbols in the time domain and may have the length of one slot, one minislot, one subframe, or one TTI. Each TTI, subframe, etc., may consist of one or more resource blocks.

[0385] One or more RBs may also be called Physical RBs (PRBs), Sub-Carrier Groups (SCGs), Resource Element Groups (REGs), PRB pairs, RB pairs, etc.

[0386] Furthermore, a resource block may consist of one or more resource elements (REs). For example, one RE may be a radio resource area comprising one subcarrier and one symbol.

[0387] A Bandwidth Part (BWP) (also called a partial bandwidth) may represent a subset of consecutive common resource blocks (RBs) for a given neurology in a given carrier. Here, the common RBs may be identified by an index of the RBs relative to the carrier's common reference point. PRBs may be defined and numbered within a BWP.

[0388] A BWP may include UL BWPs (BWPs for UL) and DL BWPs (BWPs for DL). One or more BWPs may be configured within a single carrier for a UE.

[0389] At least one of the configured BWPs may be active, and the UE does not need to assume that it will send or receive a given signal / channel outside of the active BWP. In this disclosure, terms such as "cell" and "carrier" may be read as "BWP".

[0390] The structures described above, such as wireless frames, subframes, slots, minislots, and symbols, are merely illustrative examples. For instance, the number of subframes included in a wireless frame, the number of slots per subframe or wireless frame, the number of minislots within a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, and the number of symbols, symbol length, and cyclic prefix (CP) length within a TTI can be varied in various ways.

[0391] Furthermore, the information, parameters, etc., described in this disclosure may be expressed using absolute values, relative values ​​from a predetermined value, or corresponding other information. For example, wireless resources may be indicated by a predetermined index.

[0392] The names used for parameters and other elements in this disclosure are not restrictive in any way. Furthermore, mathematical formulas and other elements that use these parameters may differ from those expressly disclosed in this disclosure. Various channels (PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, and therefore, the various names assigned to these various channels and information elements are not restrictive in any way.

[0393] The information, signals, etc. described in this disclosure may be represented using any of the various different techniques. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0394] Furthermore, information, signals, etc., can be output from upper layers to lower layers and from lower layers to upper layers, or to at least one of the two. Information, signals, etc., may also be input and output via multiple network nodes.

[0395] Input and output information and signals may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information and signals may be overwritten, updated, or appended to. Output information and signals may be deleted. Input information and signals may be transmitted to other devices.

[0396] Information notification is not limited to the embodiments described herein and may be carried out by other means. For example, information notification in this disclosure may be carried out by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof).

[0397] Physical layer signaling may also be called Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signals), L1 control information (L1 control signals), etc. RRC signaling may also be called RRC messages, for example, RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc. MAC signaling may also be communicated using, for example, MAC Control Element (CE).

[0398] Furthermore, notification of the specified information (for example, notification that "X is the case") is not limited to explicit notification, but may also be made implicitly (for example, by not providing notification of the specified information or by providing notification of other information).

[0399] The determination may be made by a value represented by 1 bit (0 or 1), by a boolean value represented as true or false, or by a numerical comparison (for example, a comparison with a predetermined value).

[0400] Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, and so on, whether they are called software, firmware, middleware, microcode, hardware description languages, or by any other name.

[0401] Furthermore, software, instructions, information, etc., may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of wired technology (such as coaxial cable, fiber optic cable, twisted pair, or Digital Subscriber Line (DSL)) and wireless technology (such as infrared or microwave), then at least one of these wired and wireless technologies is included in the definition of a transmission medium.

[0402] The terms “system” and “network” as used in this disclosure may be used interchangeably. “Network” may also mean the equipment included in the network (e.g., base stations).

[0403] In this 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," and "panel" may be used interchangeably.

[0404] In this disclosure, terms such as "Base Station (BS)", "wireless 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", and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0405] A base station can house one or more (e.g., three) cells. If a base station houses multiple cells, the entire coverage area of ​​the base station can be divided into several smaller areas, each of which may also be provided with communication services 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 ​​at least one of the base station and / or base station subsystems that provide communication services in that coverage.

[0406] In this disclosure, the transmission of information by a base station to a terminal may be interpreted as the base station instructing the terminal to perform a control / operation based on said information.

[0407] In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.

[0408] A mobile station may also be called 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 appropriate term.

[0409] 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. At least one of the base station and the mobile station may also be a device mounted on a moving object, the moving object itself, etc.

[0410] The term "mobile object" refers to any movable object, regardless of its speed, and naturally includes cases where the mobile object is stationary. Examples of such mobile objects include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcarts, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones, multicopters, quadcopters, balloons, and items carried on them. Furthermore, such mobile objects may be autonomously driven objects operating based on operational commands.

[0411] The mobile entity may be a vehicle (e.g., a car, an airplane), an unmanned mobile entity (e.g., a drone, an autonomous vehicle), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does 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.

[0412] Figure 34 shows an example of a vehicle according to one 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, an axle 48, an electronic control unit 49, various sensors (including a current sensor 50, a rotation speed sensor 51, a pneumatic 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.

[0413] The drive unit 41 consists of, for example, at least one of an engine, a motor, or an engine-motor hybrid. 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 the user.

[0414] The electronic control unit 49 consists of a microprocessor 61, memory (ROM, RAM) 62, and communication ports (e.g., input / output (IO) ports) 63. Signals from various sensors 50-58 installed in the vehicle are input to the electronic control unit 49. The electronic control unit 49 may also be called an Electronic Control Unit (ECU).

[0415] Signals from various sensors 50-58 include current signals from current sensor 50 for sensing motor current, rotational speed signals of front wheels 46 / rear wheels 47 acquired by rotational speed sensor 51, air pressure signals of front wheels 46 / rear wheels 47 acquired by air pressure sensor 52, vehicle speed signals acquired by vehicle speed sensor 53, acceleration signals acquired by acceleration sensor 54, accelerator pedal depression signal of accelerator pedal 43 acquired by accelerator pedal sensor 55, brake pedal depression signal of brake pedal 44 acquired by brake pedal sensor 56, operation signals of shift lever 45 acquired by shift lever sensor 57, and detection signals for detecting obstacles, vehicles, pedestrians, etc., acquired by object detection sensor 58.

[0416] The information service unit 59 consists of various devices for providing (outputting) various types of information such as driving information, traffic information, and entertainment information, including a car navigation system, audio system, speakers, displays, television, and radio, and one or more ECUs that control these devices. The information service unit 59 uses information acquired from external devices via a communication module 60 or the like to provide various types of information / services (e.g., multimedia information / multimedia services) to the occupants of the vehicle 40.

[0417] The information service unit 59 may include input devices that accept input from the outside (e.g., keyboard, mouse, microphone, switch, button, sensor, touch panel, etc.) and output devices that perform output to the outside (e.g., display, speaker, LED lamp, touch panel, etc.).

[0418] The driver assistance system unit 64 consists of various devices that provide functions to prevent accidents or reduce the driver's workload, 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 Unit (IMU), Inertial Navigation System (INS)), artificial intelligence (AI) chips, and AI processors, as well as one or more ECUs that control these devices. The driver assistance system unit 64 also transmits and receives various information via the communication module 60 to realize driver assistance functions or autonomous driving functions.

[0419] 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 sends and receives data (information) via the communication port 63 to 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, axle 48, the microprocessor 61 and memory (ROM, RAM) 62 in the electronic control unit 49, and various sensors 50-58 provided in the vehicle 40.

[0420] 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 external devices. For example, it can send and receive various types of information to and from external devices 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. Alternatively, the communication module 60 may be, for example, at least one of the base station 10 and the user terminal 20 (it may function as at least one of the base station 10 and the user terminal 20).

[0421] The communication module 60 may transmit at least one of the following to an external device via wireless communication: signals from the various sensors 50-58 input to the electronic control unit 49, information obtained based on said signals, and information based on input from an external source (user) obtained via the information service unit 59. The electronic control unit 49, the various sensors 50-58, the information service unit 59, etc., may also be called input units that accept input. For example, the PUSCH transmitted by the communication module 60 may include information based on the above input.

[0422] The communication module 60 receives various information (traffic information, signal information, inter-vehicle information, etc.) transmitted from an external device and displays it on the information service unit 59 installed in the vehicle. The information service unit 59 may also be called an output unit, which outputs information (for example, it outputs information to devices such as displays and speakers based on the PDSCH (or data / information decoded from the PDSCH) received by the communication module 60).

[0423] 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, axle 48, various sensors 50-58, etc., which are provided in the vehicle 40.

[0424] Furthermore, the term "base station" in this disclosure may be interpreted as "user terminal." For example, the various aspects / embodiments of this 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), Vehicle-to-Everything (V2X)). In this case, the user terminal 20 may have the functions that the base station 10 has. Also, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to terminal-to-terminal communication (for example, "sidelink"). For example, uplink channel and downlink channel may be interpreted as sidelink channel.

[0425] Similarly, the term "user terminal" in this disclosure may be replaced with "base station." In this case, the base station 10 may be configured to have the same functions as the user terminal 20 described above.

[0426] In this disclosure, operations performed by a base station may, in some cases, be performed by its upper node. In a network including one or more network nodes with base stations, it is clear that various operations performed for communication with terminals may be performed by the base station, one or more network nodes other than the base station (for example, a Mobility Management Entity (MME), a Serving Gateway (S-GW), etc., but not limited to these), or a combination thereof.

[0427] Each aspect / embodiment described in this disclosure may be used individually, in combination, or switched between during execution. Furthermore, the processing procedures, sequences, flowcharts, etc., of each aspect / embodiment described in this disclosure may be rearranged in order, provided they are consistent. For example, the methods described in this disclosure present various step elements in an exemplary order and are not limited to that specific order.

[0428] Each aspect / embodiment described in this disclosure includes 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 (where x is, for example, an integer or decimal)), 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®), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi®), IEEE 802.16 (WiMAX®), and IEEE This may apply to systems utilizing 802.20, Ultra-WideBand (UWB), Bluetooth®, or other appropriate wireless communication methods, as well as next-generation systems that are extended, modified, created, or defined based on these. It may also apply to combinations of multiple systems (e.g., a combination of LTE or LTE-A and 5G).

[0429] In this disclosure, the phrase "based on" does not mean "based solely on" unless otherwise specified. In other words, the phrase "based on" means both "based solely on" and "based at least on."

[0430] Any reference to elements using the designations “first,” “second,” etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Accordingly, the references to the first and second elements do not imply that only two elements may be employed or that the first element must precede the second element in any way.

[0431] The term “determining” as used in this disclosure may encompass a wide variety of actions. For example, “determining” may be considered to include judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiry (e.g., searching in tables, databases, or other data structures), ascertaining, etc.

[0432] Furthermore, "judgment (decision)" may be considered as "judging (deciding)" things like receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory).

[0433] Furthermore, "judgment (decision)" can be considered as "judging (deciding)" something like resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment (decision)" can be considered as "judging (deciding)" something about an action.

[0434] Furthermore, "judgment (decision)" can be replaced with "assuming," "expecting," or "considering."

[0435] The term "maximum transmit power" as used in this disclosure may mean the maximum transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0436] As used in this disclosure, the terms “connected,” “coupled,” and any variations thereof mean any direct or indirect connection or coupling between two or more elements, and may include one or more intermediate elements between two elements that are “connected” or “coupled” with each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, “connection” may be replaced with “access.”

[0437] In this disclosure, when two elements are connected, they can be considered to be “connected” or “coupled” to each other using one or more wires, cables, printed electrical connections, etc., and, in some non-exclusive and non-exclusive examples, electromagnetic energy having wavelengths in the radio frequency domain, microwave domain, or optical domain (both visible and invisible).

[0438] In this 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 "combine" may be interpreted similarly to "different."

[0439] Where the terms “include,” “including,” and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term “comprising.” Furthermore, the term “or” as used in this disclosure is not intended to mean exclusive OR.

[0440] In this disclosure, if articles are added by translation, such as a, an, and the in English, this disclosure may include the fact that the noun following these articles is plural.

[0441] In this disclosure, terms such as "less than or equal to," "less than," "greater than or equal to," "more than," and "equal to" may be interpreted interchangeably. In addition, in this disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "early," "slow," "wide," and "narrow" may be interpreted interchangeably, not limited to the positive, comparative, and superlative degrees. Furthermore, in this disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "early," "slow," "wide," and "narrow" may be interpreted interchangeably, not limited to the positive, comparative, and superlative degrees, by adding "i-th" (where i is any integer) to the expression (for example, "highest" may be interpreted interchangeably with "i-th highest").

[0442] In this disclosure, "of," "for," "regarding," "related to," and "associated with" may be interpreted as being interchangeable.

[0443] Although the invention described herein has been explained in detail above, it will be clear to those skilled in the art that the invention described herein is not limited to the embodiments described herein. The invention described herein can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined in the claims. Therefore, the descriptions herein are for illustrative purposes only and do not imply any limitation on the invention described herein.

Claims

1. A receiving unit that receives instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for a demodulated reference signal (DMRS) to which a frequency domain orthogonal cover code (FD-OCC) longer than 2 is applied, A terminal having a control unit that, when the instruction indicates two antenna ports from two CDM groups, determines that the remaining antenna port is not associated with transmitting a physical downlink shared channel (PDSCH) to another terminal, and when the instruction indicates one antenna port, determines that the remaining antenna port may be associated with transmitting a PDSCH to another terminal.

2. The steps include receiving instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for a demodulated reference signal (DMRS) to which a frequency domain orthogonal cover code (FD-OCC) longer than 2 is applied, A wireless communication method for a terminal, comprising the steps of: determining that if the instruction indicates two antenna ports from two CDM groups, the remaining antenna port is not associated with transmitting a physical downlink sharing channel (PDSCH) to another terminal; and determining that if the instruction indicates one antenna port, the remaining antenna port may be associated with transmitting a PDSCH to another terminal.

3. A transmitting unit that transmits instructions to a terminal for one or more antenna ports in one or more code division multiplexing (CDM) groups for a demodulated reference signal (DMRS) to which a frequency domain orthogonal cover code (FD-OCC) longer than 2 is applied, A base station having a control unit that, when the instruction indicates two antenna ports from two CDM groups, determines that the remaining antenna port is not associated with transmitting a physical downlink sharing channel (PDSCH) to a terminal other than the terminal, and when the instruction indicates one antenna port, determines that the remaining antenna port may be associated with transmitting a PDSCH to a terminal other than the terminal.

4. A system having terminals and base stations, The aforementioned terminal is A receiving unit that receives instructions for one or more antenna ports in one or more code division multiplexing (CDM) groups for a demodulated reference signal (DMRS) to which a frequency domain orthogonal cover code (FD-OCC) longer than 2 is applied, The control unit has the following characteristics: If the instruction indicates two antenna ports from two CDM groups, it determines that the remaining antenna port is not associated with transmitting a physical downlink shared channel (PDSCH) to another terminal; and if the instruction indicates one antenna port, it determines that the remaining antenna port may be associated with transmitting a PDSCH to another terminal. The aforementioned base station is A system having a transmitting unit that transmits the aforementioned instructions.

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