Terminal, wireless communication method, and base station

Abstract

A terminal according to an aspect of the present disclosure comprises: a control unit that determines a control channel element (CCE) index on the basis of a first derivation method pertaining to the CCE index corresponding to a candidate for a physical downlink control channel (PDCCH) using a plurality of layers, the first derivation method being different from a second derivation method pertaining to a CCE index corresponding to a candidate for a PDCCH using one layer; and a reception unit that monitors, on the basis of the determined CCE index, the PDCCH using the plurality of layers. According to the aspect of the present disclosure, resource efficiency can be improved.

Description

Terminal, wireless communication method and base station

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

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

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

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

[0005] In future wireless communication systems (e.g., NR), for example, from the viewpoint of improving resource efficiency, increasing the capacity of the downlink control channel is being considered.

[0006] However, specific methods for achieving this have not been fully explored. If this exploration is insufficient, there is a risk that improvements in resource efficiency will be hindered and increases in communication throughput will be limited.

[0007] Therefore, one of the objects of the present disclosure is to provide a terminal, a wireless communication method, and a base station that can improve resource efficiency.

[0008] A terminal according to one aspect of the present disclosure includes a control unit that determines a control channel element (CCE) index corresponding to a physical downlink control channel (PDCCH) candidate using multiple layers based on a first derivation method for the CCE index, the first derivation method being different from a second derivation method for a CCE index corresponding to a PDCCH candidate using one layer, and a receiving unit that monitors the PDCCH using multiple layers based on the CCE index.

[0009] According to one aspect of the present disclosure, resource efficiency can be improved.

[0010] FIG. 1A is a diagram showing an example of the number of UEs accommodated per slot / symbol for each channel. FIG. 1B is a diagram showing an example of the number of UEs accommodated per cell for each channel. FIGS. 2A and 2B are diagrams showing an example of overlapping resources of PDCCH candidates. FIG. 3 is a diagram showing an example of PDCCH DMRS employing FD-OCC. FIG. 4 is a diagram showing another example of PDCCH DMRS employing FD-OCC. FIG. 5 is a diagram showing another example of PDCCH DMRS employing FD-OCC. FIG. 6 is a diagram showing an example of PDCCH DMRS employing TD-OCC. FIG. 7 is a diagram showing another example of PDCCH DMRS employing TD-OCC. FIG. 8 is a diagram showing an example of PDCCH DMRS employing FD-OCC and TD-OCC. FIG. 9 is a diagram showing another example of PDCCH DMRS employing FD-OCC and TD-OCC. FIG. 10 is a diagram showing an example of PDCCH DMRS employing FDM. Fig. 11 is a diagram showing another example of PDCCH DMRS to which FDM is applied. Fig. 12 is a diagram showing an example of PDCCH DMRS to which TDM is applied. Fig. 13 is a diagram showing another example of PDCCH DMRS to which TDM is applied. Fig. 14 is a diagram showing an example of a schematic configuration of a wireless communication system according to an embodiment. Fig. 15 is a diagram showing an example of a configuration of a base station according to an embodiment. Fig. 16 is a diagram showing an example of a configuration of a user terminal according to an embodiment. Fig. 17 is a diagram showing an example of hardware configurations of a base station and a user terminal according to an embodiment. Fig. 18 is a diagram showing an example of a vehicle according to an embodiment.

[0011] (Minimum Quality Guaranteed in Future Wireless Communication Systems) In existing wireless communication systems (for example, up to Rel. 15-17), mobile communications using public networks generally employ so-called best-effort communications.

[0012] A characteristic of such communications is that telecommunications carriers cannot control sudden increases in traffic volume. For example, in crowded environments such as concerts and stadiums, if traffic suddenly increases, minimum communication standards cannot be guaranteed (for example, you cannot make phone calls or browse the web).

[0013] In existing wireless communication systems (for example, up to Rel. 15-17), mission-critical use cases (for example, Ultra-Reliable and Low Latency Communications (URLLC)) have been considered.

[0014] However, when providing mission-critical communication services over a public network, if the peripheral traffic increases as described above, or if the traffic within the mission-critical communication service increases, it may become impossible to achieve the desired communication quality (e.g., throughput / delay / number of simultaneous connections, etc.).

[0015] Therefore, future wireless communication systems will require mechanisms that can guarantee a minimum level of communication quality, whether for general users or mission-critical use cases.

[0016] However, it is difficult to guarantee a minimum quality with limited resources.

[0017] For example, if the number of users is unknown at any given time, it is difficult to guarantee a minimum quality of service for all users using limited resources.

[0018] Furthermore, the minimum quality that can be guaranteed varies depending on the performance and type of device / terminal, making it difficult to guarantee a minimum quality that can achieve the service KPIs (Key Performance Indicators) desired by all users.

[0019] Furthermore, since wireless communication quality can change from moment to moment due to various factors, it is difficult to always guarantee a specific performance KPI (for example, throughput / reliability).

[0020] Furthermore, due to limitations on the number of base stations / transmission / reception points that can be deployed, or factors such as the surrounding communication environment, it is difficult to guarantee a specific quality in any location.

[0021] As a method for correcting the minimum quality for many terminals (user terminals, User Equipment (UE)), it is conceivable to simultaneously schedule a data channel (e.g., PDSCH / PUSCH) for many UEs.

[0022] Below, an example of calculating the number of UEs multiplexed in FR1 (particularly, a case where the required throughput of VoLTE (Voice over LTE) is 12.65 kbps, the data transmission period is 20 ms, and the data size (transport block size) is 320 or more) will be described.

[0023] The calculation conditions are as follows: Band setting: FR1, 100 MHz, subcarrier spacing = 30 kHz. TDD setting: DDDSUUDDDD (5 ms period, D is DL slot, U is UL slot, S is special slot (for simplicity, only PDCCH can be transmitted)). PDCCH: Symbol #0 or #0 to #1 is used. The number of DCI bits is 40. Aggregation level is the same as or lower than the coding rate of PDSCH. PDSCH: Mapping pattern 1 is 13 symbols long and 2 symbols of DMRS (non-data multiplexing). Mapping pattern 2 is 12 symbols long and 2 symbols of DMRS (non-data multiplexing). PUSCH: Symbol length is 14 symbols and 2 symbols of DMRS (non-data multiplexing). Other reference signals (RS) / channels, etc. are not taken into consideration.

[0024] 1A is a diagram showing an example of the number of UEs accommodated per slot / symbol of each channel, in which the number of UEs accommodated per slot for each channel is calculated based on the number of RBs.

[0025] Under the above conditions, when calculating the number of UEs accommodated for PDCCH per symbol, in the case of modulation and coding scheme (MCS) index 0, 24 resource blocks (RB) are required per UE, so the calculated number of accommodated UEs is 11. In addition, in the case of MCS index 5, 12 RBs are required per UE, so the calculated number of accommodated UEs is 22.

[0026] Similarly, when calculating the number of UEs accommodated for PDSCH per slot, in the case of MCS index 0, 11 RBs are required per UE for pattern 1 and 12 RBs are required per UE for pattern 2, so the calculated number of UEs accommodated is 22 to 24. Furthermore, in the case of MCS index 5, 4 RBs are required per UE for patterns 1 and 2, so the calculated number of UEs accommodated is 68.

[0027] Furthermore, when calculating the number of UEs accommodated for PUSCH per slot, in the case of MCS index 0, 10 RBs are required per UE, so the calculated number of UEs accommodated is 27. In the case of MCS index 5, 3 RBs are required per UE, so the calculated number of UEs accommodated is 91.

[0028] 1B is a diagram illustrating an example of the number of UEs accommodated per cell for each channel, in which the number of UEs accommodated per cell for each channel (the number of DCIs for PDCCH) is calculated based on the TDD configuration.

[0029] Under the above conditions, the number of PDCCHs / DCIs per cell is calculated as follows: for MCS index 0, a 1-symbol PDCCH can accommodate 392 DCIs (UL DCIs and DL DCIs), and a 2-symbol PDCCH can accommodate 784 DCIs (UL DCIs and DL DCIs). Also, for MCS index 5, a 1-symbol PDCCH can accommodate 784 DCIs (UL DCIs and DL DCIs), and a 2-symbol PDCCH can accommodate 1568 DCIs (UL DCIs and DL DCIs).

[0030] Similarly, when calculating the number of UEs accommodated for PDSCH per cell, in the case of MCS index 0, 11 RBs are required per UE for pattern 1, so the calculated number of UEs accommodated is 672, and in the case of pattern 2, 12 RBs are required per UE, so the calculated number of UEs accommodated is 616. Furthermore, in the case of MCS index 5, 4 RBs are required per UE for patterns 1 and 2, so the calculated number of UEs accommodated is 1904.

[0031] Furthermore, when calculating the number of UEs accommodated for PUSCH per cell, in the case of MCS index 0, 10 RBs are required per UE, so the calculated number of UEs accommodated is 216. In the case of MCS index 5, 3 RBs are required per UE, so the calculated number of UEs accommodated is 728.

[0032] As such, assuming the required throughput of VoLTE, even in a TDD configuration where DL resources are greater than UL resources, it is possible to allocate PUSCH to up to 216 UEs (in the case of MCS index 0) per slot.

[0033] To schedule the PUSCHs of 216 UEs, it is necessary to transmit a control channel (eg, PDCCH / DCI) for scheduling the PUSCHs in one or more DL slots.

[0034] As mentioned above, the number of PDCCHs / DCIs per cell is at least about 400, which is considered to be sufficiently large.

[0035] However, this is only an example of a case where PDCCH / DCI can be transmitted so as to be spread across all PDCCH resources. In actual transmission, due to PDCCH overbooking, the base station cannot simultaneously transmit as many PDCCHs as the above-mentioned calculated number. In other words, if PDCCH candidate resources between UEs overlap in the time domain, a state occurs in which PDCCH cannot be transmitted.

[0036] (PDCCH Candidate) In existing wireless communication systems (up to NR Rel. 15-17), CCE indices corresponding to PDCCH candidates in CORESET: p, aggregation level: L, and search space: s are determined based on the following formula (hash function):

[0037] Here, N ＣＣＥ，ｐ is the number of CCEs in CORESETp. ＣＩ is the carrier indicator field value. （Ｌ） ｓ，ｎ＿ＣＩ is n ＣＩ is the search space s of the serving cell corresponding to the aggregation level L, and m is the number of PDCCH candidates configured to be monitored for the aggregation level L; （Ｌ） ｓ，ｎ＿ＣＩ is from 0 to M （Ｌ） ｓ，ｎ＿ＣＩ The value is up to.

[0038] Also, Y ｐ、ｎ＾μ＿ｓ、ｆ is a value determined based on at least one of the search space type, RNTI, and slot number, and in the case of CSS, Y ｐ、ｎ＾μ＿ｓ、ｆ =0.

[0039] In the case of USS, Y ｐ、ｎ＾μ＿ｓ、ｆ is determined based on the following formula:

[0040] Here, Y ｐ、ｎ＾μ＿ｓ、ｆ The initial value of Y ｐ，－１ is the value of C-RNTI (n ＲＮＴＩ ) A ｐ is 39827 if the remainder when p is divided by 3 (p mod 3) is 0, 39829 if the remainder when p is divided by 3 is 1, and 39839 if the remainder when p is divided by 3 is 2. D is 65537.

[0041] In other words, according to the above formula, in the case of USS, the CCE indexes that are PDCCH candidates differ for each UE and for each slot.

[0042] This calculation method makes it possible to maximize frequency diversity for each UE and randomize interference between cells, but it makes it difficult to schedule overlapping PDCCH candidate resources between specific UEs.

[0043] This is Y ｐ、ｎ＾μ＿ｓ、ｆ CORESET index / Y ｐ，－１ It is highly likely that the value of C-RNTI (for example, any value between 0 and 65535) will be different for each UE, and Y ｐ、ｎ＾μ＿ｓ、ｆ The initial value of Y ｐ，－１ Since Y is basically different for each UE, Y is calculated for multiple UEs (multiple UEs with low spatial correlation). ｐ、ｎ＾μ＿ｓ、ｆ This is because it is difficult to make them the same value.

[0044] In other words, since it is difficult to set the CCE index to the same value for multiple UEs (multiple UEs with low spatial correlation), it is difficult to overlap PDCCH candidate resources for multiple UEs (multiple UEs with low spatial correlation).

[0045] In the above formula 1 in the existing specifications, the CCE indexes that are PDCCH candidates vary depending on the number of CCEs, the number of PDCCHs to be monitored (number of candidates), and the value of RNTI. The number of CCEs is determined based on the number of RBs / number of symbols in the CORESET. The number of CCEs is also determined based on the number of RBs / number of symbols in the CORESET.

[0046] In the existing specifications, a CCE index is assigned to each REG bundle. When each REG bundle is interleaved, the monitored PRB is assigned a shift index (shiftIndex(n)) related to the interleaving. ｓｈｉｆｔ )), the interleaver size (interleaverSize(R)) and the bundle size of REG (reg-BundleSize(L)).

[0047] Therefore, when it is desired to dynamically change the CCE index as described below, it is necessary to dynamically change at least one of the number of CCEs, the number of PDCCHs to be monitored, and the RNTI value.

[0048] (Analysis) As described above, in order to simultaneously schedule data channels (e.g., PDSCH / PUSCH) for many UEs as a method for compensating for minimum quality, a technique for improving frequency / space utilization efficiency is required to allocate PDCCHs capable of accommodating many more UEs using limited resources. In other words, in order to compensate for minimum quality, a method for increasing PDCCH capacity is required.

[0049] More specifically, there is a demand for technologies / methods that enable communication at low data rates even when the resources that can be allocated to one UE are limited, and technologies / methods that improve the frequency utilization efficiency of resources (e.g., spatial multiplexing of channels / signals).

[0050] Also, from the perspective of improving general resource efficiency in future wireless communication systems, it is preferable to increase the PDCCH capacity.

[0051] For example, when multiple layers / ports are used for the PDCCH (e.g., when multi-user (MU-) MIMO is used for the PDCCH), UEs with low spatial correlation need to share at least some of the PDCCH candidates (resources for PDCCH candidates).

[0052] For example, if the spatial correlation between UE #1 and UE #2 is low, it is preferable to enable scheduling such that at least some of the resources of PDCCH candidates overlap in all / specific search spaces / CORESETs.

[0053] FIG. 2A shows an example where PDCCH candidate resources overlap for multiple UEs (UE #1 and UE #2) in a particular search space / CORESET (SS #1 in the example shown in FIG. 2A).

[0054] Figure 2B shows an example in which PDCCH candidate resources overlap for multiple UEs (UE #1 and UE #2) in all search spaces / CORESETs (SS #1 and SS #2 in the example shown in Figure 2B).

[0055] However, as described above, when determining PDCCH candidate resources based on a hash function defined in existing specifications, it is difficult to overlap PDCCH candidate resources for multiple UEs (multiple UEs with low spatial correlation). Therefore, a method for overlapping PDCCH candidate resources for multiple UEs is required.

[0056] However, such methods have not been sufficiently studied. If they are not sufficiently studied, it may not be possible to guarantee a minimum quality of communication, and an increase in communication throughput may be inhibited.

[0057] Therefore, the present inventors came up with a method for solving the above problem.

[0058] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. Wireless communication methods according to the embodiments may be applied independently or in combination.

[0059] In the present disclosure, "A / B" and "at least one of A and B" may be interpreted interchangeably. Also, in the present disclosure, "A / B / C" may mean "at least one of A, B, and C."

[0060] In the present disclosure, terms such as notify, activate, deactivate, indicate (or indicate), select, configure, update, and determine may be read interchangeably. In the present disclosure, terms such as support, control, controllable, operate, and operate may be read interchangeably.

[0061] In the present disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, higher layer parameters, fields, information elements (IEs), settings, etc. may be interchangeable. In the present disclosure, Medium Access Control (MAC) control elements (CEs), update commands, activation / deactivation commands, etc. may be interchangeable.

[0062] In the present disclosure, the higher layer signaling may be, for example, any one of Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, other messages (e.g., messages from the core network such as positioning protocol (e.g., NR Positioning Protocol A (NRPPa) / LTE Positioning Protocol (LPP)) messages), or a combination thereof.

[0063] In the present disclosure, MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. Broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

[0064] In the present disclosure, physical layer signaling may be, for example, Downlink Control Information (DCI), Uplink Control Information (UCI), and the like.

[0065] In the present disclosure, the terms drop, abort, cancel, puncture, rate match, postpone, do not transmit, etc. may be read interchangeably.

[0066] (Wireless Communication Method) A UE may receive PDCCH with more than one rank / layer.

[0067] By receiving the PDCCH using multiple ranks / layers, the frequency resources (e.g., aggregation level) for transmitting the PDCCH with a required coding rate can be reduced, and the multiplexing capacity / accommodation capacity (PDCCH capacity) of the UE can be improved.

[0068] Each embodiment of the present disclosure may be applied only when a specific parameter / field is configured using higher layer signaling (e.g., RRC signaling / MAC CE).

[0069] For example, the number of receiving layers / ranks of the PDCCH may be configured for the UE using higher layer signaling, and the UE may receive DCI using the configured number of layers / ranks.

[0070] For example, the maximum number of layers / maximum ranks for receiving a PDCCH may be configured for a UE using higher layer signaling, and the UE may receive DCI using a number of layers / ranks that is less than or equal to the configured maximum number of layers / maximum ranks.

[0071] The configuration by the higher layer signaling may be performed, for example, for each search space / CORESET / BWP / CC / band / UE.

[0072] Each embodiment of the present disclosure may be applied only when specific UE capability information (support for specific UE capabilities) is reported.

[0073] The UE capability information may be reported, for example, per band, per band combination (BC), per band within a BC, or per band within a BC per CC (per CC per band in BC).

[0074] Each embodiment of the present disclosure may be applied to a specific search space (SS) / SS set.

[0075] The specific SS / SS set may be, for example, a UE-specific search space (USS) or a specific common search space (CSS, for example, Type 3 CSS). By configuring in this way, for example, a configuration can be achieved in which a CSS for multiple UEs of Type 0 / 0A / 1 / 2 CSS is excluded.

[0076] Each embodiment of the present disclosure may be applied to a specific DCI format (or a PDCCH that carries the DCI format).

[0077] The specific DCI format may be, for example, a DCI format excluding a DCI format common to a group (e.g., DCI format 2_x (x is any integer)) and a DCI format for multicast / broadcast (e.g., DCI format 4_x (x is any integer)). By configuring in this way, it is possible to achieve a configuration excluding DCI formats for multiple UEs.

[0078] The specific DCI format may be, for example, at least one of a group-common DCI format (e.g., DCI format 2_x (x is any integer)) and a multicast / broadcast DCI format (e.g., DCI format 4_x (x is any integer)).

[0079] Each embodiment of the present disclosure may be applicable for a particular time resource (eg, slot / symbol).

[0080] The specific time resource may be, for example, a DL / UL / special slot (or symbol).

[0081] Each embodiment of the present disclosure may be applied to, for example, a specific BWP / CC.

[0082] For example, the specific BWP / CC may be, for example, a BWP / CC of a PCell / PSCell / SpCell, or a BWP / CC of an SCell.

[0083] In each embodiment of the present disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "layer," "number of layers," "rank," "resource," "resource set," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," "UE panel," "transmitting entity," and "receiving entity" may be read interchangeably.

[0084] In each embodiment of the present disclosure, MIMO (Multi-Input Multi-Output), multi-layer, and multi-port may be interchangeable.

[0085] Each embodiment of the present disclosure may operate, for example, for MIMO with multiple UEs (multi-user (MU-) MIMO). In this disclosure, MU-MIMO may refer to transmission / reception of signals / channels using multiple layers / ports / ranks in multiple UEs, with at least some time / space resources overlapping.

[0086] In each embodiment of the present disclosure, MU-MIMO, PDCCH-MIMO, transmission / reception using multiple layers / ports, multi-layer / port PDCCH, and transmission / reception using multiple (two or more) ports / port numbers / port indices may be read as interchangeable.

[0087] In each embodiment of the present disclosure, the PDCCH resources of one UE and the PDCCH resources of another UE may overlap in a particular search space / CORESET.

[0088] The overlap of resources for multiple UEs may be partial overlap of the resources or full overlap of the resources.

[0089] In the present disclosure, the CCE index that is a PDCCH candidate, the CCE index that corresponds to the PDCCH candidate, and the CCE index of the PDCCH candidate may be read as interchangeable.

[0090] First Embodiment The first embodiment relates to derivation of CCE indices that are PDCCH candidates.

[0091] The first embodiment is roughly divided into embodiments 1-1 and 1-2. The UE / base station may apply either embodiment 1-1 or 1-2, or may apply a combination of embodiments 1-1 and 1-2.

[0092] <<Embodiment 1-1>> A UE may derive / identify CCE indices that are PDCCH candidates based on a specific formula / method / rule.

[0093] The specific formula / method / rule may be, for example, a formula (second formula) different from Formula 1 above.

[0094] The second formula may not be determined based on at least one of a specific Radio Network Temporary Identifier (RNTI), a CORESET index, and a search space. In other words, the second formula may not include at least one of a term related to a specific RNTI, a term related to a CORESET index, and a term related to a search space.

[0095] <<Embodiment 1-2>> The second formula is a formula that includes a specific term (for example, Y ｐ、ｎ＾μ＿ｓ、ｆ The second formula may be different depending on the specific terms (e.g., Y ｐ、ｎ＾μ＿ｓ、ｆ ) and different terms (e.g., Y'ｐ、ｎ＾μ＿ｓ、ｆ ) may be included.

[0096] In the second equation, the different term may be a term that is not based on at least one of a specific RNTI (eg, C-RNTI) value, a CORESET index, and a search space.

[0097] In the second equation, the different term may be a term that is not dependent on (based on) the slot.

[0098] According to the first embodiment described above, overlapping of PDCCH candidate resources for multiple UEs can be achieved without using an existing method for deriving CCE indices.

[0099] Second Embodiment The second embodiment is a modification of the first embodiment, in which "different terms (for example, Y' ｐ、ｎ＾μ＿ｓ、ｆ )

[0100] Y' ｐ、ｎ＾μ＿ｓ、ｆ may be defined by a recurrence formula based on a specific time resource (e.g., symbol / slot). ｐ、ｎ＾μ＿ｓ、ｆ may be derived based on Y'p, (n^μ_s,f)-1.

[0101] The second embodiment is roughly divided into embodiments 2-1 to 2-3. The UE / base station may apply any one of embodiments 2-1 to 2-3, or may apply a combination of at least two of embodiments 2-1 to 2-3.

[0102] Embodiment 2-1 Y' ｐ、ｎ＾μ＿ｓ、ｆ is the initial value corresponding to slot number 0 (for example, Y' ｐ、－１ ) may be determined based on the

[0103] For example, the UE may determine the initial value based on parameters set / instructed according to at least one of the methods described in Supplementary Note 1 below.

[0104] For example, the UE may determine the initial value based on a particular RNTI value and / or the parameter.

[0105] For example, the UE may calculate the initial value by adding / subtracting / multiplying / dividing the parameter to / from a specific RNTI value.

[0106] For example, the UE may determine the parameter as the initial value.

[0107] For example, the UE may be configured / instructed to use a specific RNTI to determine the CCE indexes that are PDCCH candidates, and the UE may determine the initial value based on the specific RNTI value.

[0108] The RNTI (first RNTI) used to calculate PDCCH candidates (CCE indices that become PDCCH candidates) and the RNTI (second RNTI) used to detect PDCCHs may be defined separately.

[0109] For example, the first RNTI may be a group-common RNTI (e.g., G (Group)-RNTI, G-CS (Configured Scheduling)-RNTI), a new RNTI, or a UE-specific RNTI (e.g., C (Cell)-RNTI, CS-RNTI). For example, the second RNTI may be a UE-specific RNTI (e.g., C-RNTI, CS-RNTI), or a group-common RNTI (e.g., G-RNTI, G-CS-RNTI).

[0110] For example, the UE may determine the CCE index of the PDCCH candidate based on the first RNTI and detect the PDCCH whose CRC is scrambled based on the second RNTI. This configuration allows the UE to flexibly change the position of the PDCCH candidate without updating / resetting the RNTI value used for detection.

[0111] Each of the first RNTI and the second RNTI may be set using higher layer signaling (RRC / MAC CE), or may be determined based on a predefined rule.

[0112] The UE may assume that the first RNTI is commonly assigned to multiple UEs in the cell, and that the second RNTI is not assigned to any other UE in the cell (is UE-specific).

[0113] The UE may assume that the first RNTI is not assigned to any other UE in the cell (is UE-specific), and that the second RNTI is assigned commonly to multiple UEs in the cell.

[0114] <<Embodiment 2-2>> Also, Y' ｐ、ｎ＾μ＿ｓ、ｆ is a term related to the CORESET index (e.g., A' ｐ ) may be determined based on the

[0115] For example, Y' ｐ、ｎ＾μ＿ｓ、ｆ is A' ｐ *Y'p, may be determined based on (n^μ_s,f)-1.

[0116] For example, the UE may ｐ may be determined based on parameters set / instructed according to at least one of the methods described in Supplementary Note 1 below.

[0117] For example, the UE may determine A' based on at least one of the CORESET index and the parameter. ｐ may be determined.

[0118] For example, the UE calculates A′ based on the value obtained by adding / subtracting / multiplying / dividing the parameter to / from the CORESET index. ｐ may be determined.

[0119] For example, the UE may add / subtract / multiply / divide the parameter to / from the CORESET index, and then divide the result by 3 to obtain A' ｐ It may be determined as:

[0120] For example, the UE may set the parameter as A' ｐ It may be judged as such.

[0121] <<Embodiment 2-3>> Also, Y' ｐ、ｎ＾μ＿ｓ、ｆ may be determined based on a particular term (eg, D').

[0122] For example, Y' ｐ、ｎ＾μ＿ｓ、ｆ is A' ｐ *Y'p, remainder when (n^μ_s, f)-1 is divided by D' ((A' ｐ *Y'p, (n^μ_s,f)-1) mod D').

[0123] For example, D′ may be a specific value (a fixed value). The specific value may be, for example, 65537, or may be a value different from 65537.

[0124] For example, the UE may determine D' based on at least one of parameters set / instructed according to at least one of the methods described in Supplementary Note 1 below and reported UE capability information.

[0125] For example, the UE may determine D' based on a particular value (eg, 65537 or a value other than 65537) and / or the parameter.

[0126] For example, the UE may determine D' based on the particular value plus / minus / multiply / divide the parameter.

[0127] When D' is determined based on the parameter divided by the particular value, the decimal point may be rounded up or down. In other words, D' may be defined as the output of the floor / ceiling function for the parameter divided by the particular value.

[0128] For example, the UE may determine the parameter as D'.

[0129] As described above, according to the second embodiment, it is possible to derive CCE indices that enable overlapping of PDCCH candidate resources for multiple UEs.

[0130] <Variations of the First and Second Embodiments> The UE may assume / determine that the above-described Embodiments 1-1 / 1-2 / 2-1 / 2-2 / 2-3 are applicable when certain conditions are met.

[0131] The specific condition may be at least one of the following: - When the UE reports a UE capability indicating that it supports multi-layer PDCCH (PDCCH MIMO) with different UEs. - When the UE is configured / instructed to use specific parameters based on at least one of the methods described in Supplementary Note 1 below.

[0132] The UE may determine / decide to apply the above embodiment 1-1 / 1-2 / 2-1 / 2-2 / 2-3 for each UE / each scheduling cell / each scheduled cell (cell scheduled in DCI) / each CORESET / each search space.

[0133] For example, the UE may determine / decide to apply the above embodiment 1-1 / 1-2 / 2-1 / 2-2 / 2-3 to a CORESET of a specific CORESET index, and may determine / decide not to apply the above embodiment 1-1 / 1-2 / 2-1 / 2-2 / 2-3 to other CORESETs.

[0134] The UE / base station may determine to which UE / scheduling cell / scheduled cell / CORESET / search space the above-mentioned embodiments 1-1 / 1-2 / 2-1 / 2-2 / 2-3 are applied based on at least one of a predefined specific rule, a reported UE capability, and at least one method / parameter / information / signal / channel (e.g., RRC / MAC CE / DCI, etc.) described in Supplementary Note 1 below.

[0135] <Third Embodiment> The third embodiment relates to changing / instructing / determining the number of CCEs, the number of PDCCHs to be monitored, and the RNTI value.

[0136] The CCE index may be determined based on at least one of the number of CCEs, the number of PDCCHs to monitor, and the RNTI value.

[0137] The number of CCEs may be determined based on the number of frequency resources (e.g., the number of RBs) / the number of time resources (e.g., the number of symbols) of the CORESET.

[0138] The third embodiment is roughly divided into embodiments 3-1 to 3-4. The UE / base station may apply any one of embodiments 3-1 to 3-4, or may apply a combination of at least two of embodiments 3-1 to 3-4.

[0139] The indication information in each of the following embodiments may be provided using, for example, (a specific field / parameter included in) MAC CE / DCI.

[0140] <<Embodiment 3-1>> The UE may update / change / determine the RNTI value based on the received instruction information.

[0141] The instruction information may include, for example, at least one of the following information: - Information indicating which RNTI (e.g., C-RNTI / MCS (Modulation Coding Scheme)-C-RNTI) value to update / change / determine. - Information / parameter indicating the updated / changed value of the RNTI.

[0142] The UE may determine the updated / modified value based on the information / parameter indicating the updated / modified value:

[0143] For example, the UE may assume / determine that a configured / indicated RNTI (e.g., the first RNTI described above) is selected to determine the CCE index that is a PDCCH candidate, and may update / change / determine the RNTI value.

[0144] For example, the UE may determine that the updated / changed value is the value obtained by adding / subtracting / multiplying / dividing the notified information / parameter to / from the existing (current) value.

[0145] When the updated / changed value is determined based on the value obtained by dividing the notified information / parameter by the existing (current) value, the decimal point may be rounded up / down. In other words, the updated / changed value may be defined as the output of a floor function / ceiling function for the value obtained by dividing the notified information / parameter by the existing (current) value.

[0146] For example, the UE may determine that the value notified by the information / parameter is the updated / changed value.

[0147] <<Embodiment 3-2>> The UE may update / change / determine the number of PDCCHs (the number of PDCCH candidates) to monitor based on the received instruction information.

[0148] The number of PDCCHs to be monitored (the number of PDCCH candidates) may be the number for each aggregation level.

[0149] The instruction information may include, for example, at least one of the following information: - Information indicating for which search space the number of PDCCH candidates is to be updated / changed / determined. - Information indicating for which serving cell the number of PDCCH candidates is to be updated / changed / determined. - Information indicating for which aggregation level the number of PDCCH candidates is to be updated / changed / determined. - Information indicating for which DCI format the number of PDCCH candidates is to be updated / changed / determined. - Information / parameter indicating the updated / changed value of the number of PDCCH candidates to be monitored for each aggregation level.

[0150] For example, the UE may determine that the updated / changed value is the value obtained by adding / subtracting / multiplying / dividing the notified information / parameter to / from the existing (current) value.

[0151] When the updated / changed value is determined based on the value obtained by dividing the notified information / parameter by the existing (current) value, the decimal point may be rounded up / down. In other words, the updated / changed value may be defined as the output of a floor function / ceiling function for the value obtained by dividing the notified information / parameter by the existing (current) value.

[0152] For example, the UE may determine that the value notified by the information / parameter is the updated / changed value.

[0153] <<Embodiment 3-3>> Based on the received instruction information, the UE may update / change / determine at least one of a setting related to CORESET and a setting related to a mapping between CCEs and resource element groups (REGs) (CCE to REG mapping).

[0154] The instruction information may include, for example, at least one of the following information: Information indicating which CORESET settings are to be updated / changed / determined. Information indicating which serving cell's CORESET settings are to be updated / changed / determined. Information / parameters indicating updated / changed values ​​of frequency resources of the CORESET. Information / parameters indicating updated / changed values ​​of time resources (e.g., number of symbols) of the CORESET. Information / parameters indicating whether or not to interleave the association between CCE and REG mapping. Shift index (shiftIndex(n)) related to the interleaving. ｓｈｉｆｔ ) Information / parameters indicating the updated / changed value of the interleaver size (interleaverSize(R)). Information / parameters indicating the updated / changed value of the interleaver size (interleaverSize(R)). Information / parameters indicating the updated / changed value of the REG bundle size (reg-BundleSize(L)). Information / parameters indicating which parameters / values ​​to update / change.

[0155] For example, the UE may determine that the updated / changed value is the value obtained by adding / subtracting / multiplying / dividing the notified information / parameter to / from the existing (current) value.

[0156] When the updated / changed value is determined based on the value obtained by dividing the notified information / parameter by the existing (current) value, the decimal point may be rounded up / down. In other words, the updated / changed value may be defined as the output of a floor function / ceiling function for the value obtained by dividing the notified information / parameter by the existing (current) value.

[0157] For example, the UE may determine that the value notified by the information / parameter is the updated / changed value.

[0158] <<Embodiment 3-4>> Based on the received instruction information, the UE may update / change / determine the mapping / association between a specific DCI field (e.g., a carrier indicator field (CIF)) and a scheduled serving cell.

[0159] The indication information may include, for example, at least one of the following information: - Information indicating which scheduling cell the configuration for which is to be updated / changed / determined. - Information indicating which scheduled cell the configuration for which is to be updated / changed / determined. - Information / parameter indicating the updated / changed value of the CIF value indicating the cell that specifies the DCI (e.g., (UL) grant / (DL) assignment).

[0160] For example, the UE may determine that the updated / changed value is the value obtained by adding / subtracting / multiplying / dividing the notified information / parameter to / from the existing (current) value.

[0161] When the updated / changed value is determined based on the value obtained by dividing the notified information / parameter by the existing (current) value, the decimal point may be rounded up / down. In other words, the updated / changed value may be defined as the output of a floor function / ceiling function for the value obtained by dividing the notified information / parameter by the existing (current) value.

[0162] For example, the UE may determine that the value notified by the information / parameter is the updated / changed value.

[0163] Note that the same MAC CE / DCI may be used for at least two pieces of indication information in the above-described embodiments 3-1 to 3-4, or different MAC CE / DCI may be used. For example, the UE may update / change the indication information based on the same MAC CE / DCI or different MAC CE / DCI for at least two pieces of indication information in the above-described embodiments 3-1 to 3-4.

[0164] According to the third embodiment described above, by flexibly updating / changing the number of CCEs, the number of PDCCHs to be monitored, and the RNTI value, it is possible to derive a CCE index that enables overlapping of PDCCH candidate resources for multiple UEs.

[0165] <Fourth Embodiment> The fourth embodiment relates to restrictions / regulations on antenna ports and restrictions / regulations between multiple UEs.

[0166] In existing specifications (up to Rel. 17), when a PDSCH is transmitted to a UE using a specific antenna port, the UE may assume that other UEs are using other antenna ports.

[0167] In other words, the UE may assume that the antenna port that is orthogonal to the antenna port of the scheduled PDSCH is not associated with a PDSCH for another UE.

[0168] Also, when a specific RRC parameter (e.g., dmrs-FD-OCC-DisabledForRank1-PDSCH) is configured and PDSCH is scheduled using a single DMRS port, the UE may use different FD-OCC parameters (e.g., sequence element, w ｆ It may be assumed that a set of orthogonal DMRS antenna ports (i.e., DMRS antenna ports that are orthogonal by FD-OCC) from the same CDM group using a set of (k′)) is not associated with a PDSCH for another UE.

[0169] However, in order to improve detection accuracy in receiving multi-layer PDCCHs, it is desirable for a UE to perform detection for all ports in the same CDM group. Therefore, if a UE can decode X ports, it is desirable to limit the number of DMRS ports of all UEs in the CDM group to which DMRS is assigned to X ports or less (Problem 4a).

[0170] Furthermore, when multi-layer transmission (multi-user (MU-) MIMO) is performed between a UE that supports a multi-layer PDCCH (PDCCH MIMO) and a UE that does not support a multi-layer PDCCH (PDCCH MIMO), the latter UE in particular is subject to interference (problem 4b).

[0171] Therefore, methods for solving these problems 4a and 4b (embodiments 4-1 and 4-2, respectively) will be described below.

[0172] <<Embodiment 4-1>> A UE may assume that antenna ports orthogonal to the antenna port that receives the PDCCH (the remaining antenna ports) are not associated with PDCCH / PDSCH transmission to other UEs.

[0173] The UE may also assume that certain antenna ports that are orthogonal to the antenna port that receives the PDCCH (the remaining antenna ports) are not associated with PDCCH / PDSCH transmissions to other UEs.

[0174] The specific antenna port may be, for example, an antenna port (remaining antenna port) that is orthogonal to the antenna port that receives the PDCCH and for which FDM / TDM / FD-OCC / TD-OCC is not used for the DMRS (or FDM / TDM / FD-OCC / TD-OCC is used for the DMRS).

[0175] The FDM / TDM / FD-OCC / TD-OCC of DMRS will be described later.

[0176] For example, the PDSCH / PDCCH associated with an antenna port that receives the PDCCH and an antenna port in which DMRS does not use FDM / TDM and is orthogonal to each other may not be transmitted to other UEs.

[0177] By configuring in this manner, for example, when PDCCH DMRS of multiple UEs are multiplexed using FD-OCC / TD-OCC, it is necessary to decode the OCC and estimate the channel of the DMRS port of the other UE, whereas when it is assumed that the antenna port and DMRS of the other UE are FDM / TDM, it is not necessary to decode the OCC of the DMRS port of the other UE and estimate the channel.

[0178] The UE may also assume that certain antenna ports that are orthogonal to the antenna port that receives the PDCCH (the remaining certain antenna ports) are not associated with PDCCH / PDSCH transmissions to other UEs.

[0179] By configuring in this manner, it is possible to ensure that the use of a specific antenna port is restricted, and it is possible to reduce channel estimation using the DMRS corresponding to that antenna port.

[0180] The specific antenna port may be determined based on, for example, one or more values ​​related to at least one of the following: the antenna port associated with the receiving PDCCH, the length (sequence length) of the FD-OCC / TD-OCC of the DMRS, a parameter set / indicated using at least one of the parameters described in Supplementary Note 1 below, and a parameter reported using the UE capability information.

[0181] <<Embodiment 4-2>> For a UE that supports MU-MIMO PDCCH (a UE that supports reception of PDCCH using multiple (two or more) ports / port numbers / port indices), "another UE" in the above embodiment 4-1 may be read as "another UE that does not support MU-MIMO PDCCH (a UE that can only receive PDCCH using one port / port number / port index)."

[0182] Furthermore, for UEs that do not support MU-MIMO PDCCHs (UEs that can only receive PDCCHs using one port / port number / port index), the "other UEs" in the above embodiment 4-1 may be read as "UEs that support other MU-MIMO PDCCHs (UEs that support reception of PDCCHs using multiple (two or more) ports / port numbers / port indexes)."

[0183] Embodiment 4-3 The application of at least one of the operations / restrictions described in the above-mentioned Embodiments 4-1 and 4-2 may be determined based on at least one of the following cases: When a UE receives a PDCCH associated with a specific antenna port. When the number of ports associated with the received PDCCH is a specific value. When the number of ports associated with the received PDCCH is greater than (or equal to) / less than (or equal to) a specific value. When the number of ports associated with / not associated with FDM / TDM / FD-OCC / TD-OCC and associated with the received PDCCH (DMRS) is a specific value. When the number of ports associated with / not associated with FDM / TDM / FD-OCC / TD-OCC and associated with the received PDCCH (DMRS) is greater than (or equal to) / less than (or equal to) a specific value. When configured using higher layer signaling (RRC / MAC CE). When a UE supports / does not support a specific capability.

[0184] Note that "in a relationship of FDM / TDM / FD-OCC / TD-OCC" may be read as "orthogonal / multiplexed using FDM / TDM / FD-OCC / TD-OCC." Also, "not in a relationship of FDM / TDM / FD-OCC / TD-OCC" may be read as "not orthogonal / multiplexed using FDM / TDM / FD-OCC / TD-OCC."

[0185] In addition, the specific values ​​for each of the above conditions may be determined based on at least one of predefined rules, parameters based on at least one of the methods described in Supplementary Note 1 below, and reporting of UE capability information.

[0186] According to the fourth embodiment described above, it is possible to specify appropriate reception operations for PDCCHs using multiple layers / ports.

[0187] Fifth Embodiment The fifth embodiment relates to a demodulation reference signal (DMRS) of a PDCCH using multiple layers / ports.

[0188] In the following, the present embodiment will be described mainly using a case of two ports / layer as an example, but the number of layers / ports / ranks is not limited to this. For example, ports / layers greater than two (e.g., 3, 4, 5, 6, 7, 8, or more) may be defined, and the present embodiment may be applied to those ports / layers.

[0189] The application of multi-port PDCCH DMRS may be configured per SS / per CORESET / per DL BWP / per UL BWP / per CC / per UE.

[0190] The multi-porting of PDCCH DMRS may be realized based on one or more methods. The method may be only one of the following, or at least two of the following may be defined, and switching between them may be performed using higher layer signaling (RRC / MAC CE) / DCI: FD-OCC, TD-OCC, FD-OCC+TD-OCC, FDM, or TDM.

[0191] [FD-OCC] DMRS (PDCCH DMRS) symbols corresponding to different ports / layers may be mapped in specific time / frequency resources.

[0192] The DMRS may be mapped according to a method defined in existing specifications (up to Rel. 17) or may be mapped based on a new rule. For example, the new rule may be at least one of shifting the mapping position of the DMRS in the time direction and increasing / decreasing the density of the DMRS in the frequency direction compared to the method defined in the existing specifications (for example, when PDCCHs of multiple ports / layers are not configured / indicated).

[0193] In this case, a frequency domain (FD-) orthogonal cover code (OCC) may be applied to the DMRS symbol for each physical resource block (PRB) / precoding resource group (PRG) / control channel element (CCE) / PRG bundle size.

[0194] For the DMRS symbol, different FD-OCC parameters (which may be referred to as sequence elements, etc.) W ｆ (k) may also be applied.

[0195] 3 is a diagram showing an example of PDCCH DMRS to which FD-OCC is applied. Fig. 3 shows an example in which a CCE is configured with 14 symbols and 2 PRBs (2*12 subcarriers). The grid in the time direction indicates symbols, and the grid in the frequency direction indicates subcarriers (the same applies to the following drawings related to DMRS).

[0196] In the example shown in FIG. 3, DMRS using three ports (DMRS ports #0 to #2) is mapped in the start symbol, and FD-OCC (FD-OCC parameter W ｆ (k)) is applied.

[0197] 4 is a diagram showing another example of PDCCH DMRS to which FD-OCC is applied. In the example shown in FIG. 4, DMRS using 6 ports (DMRS ports #0 to #5) is mapped in the start symbol, and FD-OCC (FD-OCC parameter W ｆ (k)) is applied.

[0198] 5 is a diagram illustrating another example of PDCCH DMRS to which FD-OCC is applied. In the example shown in FIG. 5, DMRS using two ports (DMRS ports #0 and #1) is mapped in the start symbol, and FD-OCC (FD-OCC parameter W ｆ (k)) is applied.

[0199] [TD-OCC] DMRS (PDCCH DMRS) symbols corresponding to different ports / layers may be mapped in specific time / frequency resources.

[0200] In this case, a time domain (TD-) OCC may be applied to the DMRS symbol in a specific time resource unit (e.g., symbol unit).

[0201] Furthermore, when repeated transmission (repetition) of the PDCCH is configured, TD-OCC may be applied for each repeated transmission (between repeated transmissions).

[0202] In the repeated transmission, for example, a PDCCH corresponding to a first rank / layer may be transmitted in a first repetition, and a PDCCH corresponding to a second rank / layer may be transmitted in a second repetition (the same applies to the third repetition and subsequent repetitions and the third rank / layer and subsequent repetitions).Furthermore, in the repeated transmission, for example, PDCCHs corresponding to a plurality of ranks / layers (for example, the first to n-th ranks / layers) may be transmitted in each repetition.

[0203] TD-OCC may be applied when the duration in CORESET is greater than one.

[0204] For the DMRS symbol, different TD-OCC parameters (which may be referred to as sequence elements, etc.) W ｔ (k) may also be applied.

[0205] 6 is a diagram showing an example of PDCCH DMRS to which TD-OCC is applied. In the example shown in FIG. 6, DMRS using three ports (DMRS ports #0 to #2) is mapped over three symbols from the start symbol, and a TD-OCC of length 3 (TD-OCC parameter W ｔ (k)) is applied to the DMRS symbol.

[0206] 7 is a diagram showing another example of PDCCH DMRS to which TD-OCC is applied. In the example shown in FIG. 7, DMRS using two ports (DMRS ports #0 and #2) is mapped over two symbols from the start symbol, and a TD-OCC of length 2 (TD-OCC parameter W ｔ (k)) is applied to the DMRS symbol.

[0207] [FD-OCC+TD-OCC] The application of the FD-OCC and the application of the TD-OCC may be combined.

[0208] DMRS (PDCCH DMRS) symbols corresponding to different ports / layers may be mapped in specific time / frequency resources.

[0209] In this case, a frequency domain (FD-) orthogonal cover code (OCC) may be applied to the DMRS symbol for each physical resource block (PRB) / precoding resource group (PRG) / control channel element (CCE) / PRG bundle size.

[0210] Furthermore, a time domain (TD-) OCC may be applied to the DMRS symbol in a specific time resource unit (e.g., symbol unit).

[0211] For the DMRS symbol, different FD-OCC parameters W ｆ (k), and the parameters W of different TD-OCCs ｔ (k) may also be applied.

[0212] By configuring in this way, the receiving side (for example, UE) can decode DMRS more flexibly by using either FD-OCC or TD-OCC. For example, when the channel delay spread is large, the performance of FD-OCC deteriorates, so performance improvement can be expected by decoding DMRS using TD-OCC. Also, when the UE speed is high, the performance of TD-OCC deteriorates, so performance improvement can be expected by decoding DMRS using FD-OCC.

[0213] The UE may use either the FD-OCC or the TD-OCC to receive the DMRS based on certain conditions. For example, the UE may use the TD-OCC to decode the DMRS when a first condition is met (e.g., when the channel delay spread is large), and may use the FD-OCC to decode the DMRS when a second condition is met (e.g., when the UE's velocity is high).

[0214] 8 is a diagram showing an example of PDCCH DMRS to which FD-OCC and TD-OCC are applied. In the example shown in FIG. 8, DMRS using three ports (DMRS ports #0 to #2) is mapped over three symbols from the start symbol in a specific subcarrier, and FD-OCC (FD-OCC parameter W ｆ (k)) is also a TD-OCC of length 3 (TD-OCC parameter W ｔ (k)) are applied to each DMRS symbol.

[0215] 9 is a diagram showing another example of PDCCH DMRS to which FD-OCC and TD-OCC are applied. In the example shown in FIG. 9, DMRS using two ports (DMRS ports #0 to #1) is mapped over two symbols from the start symbol in specific subcarriers, and FD-OCC (FD-OCC parameter W ｆ (k)) is also a TD-OCC of length 2 (TD-OCC parameter W ｔ (k)) are applied to each DMRS symbol.

[0216] [FDM] DMRS (PDCCH DMRS) symbols corresponding to different ports / layers may be frequency division multiplexed (FDM) (in the same time resource / symbol).

[0217] In this case, some DMRS may not be transmitted, so that DMRS symbols corresponding to different ports / layers may be FDM-multiplexed.

[0218] For example, only DMRS symbols corresponding to ports / layers configured / instructed to the UE may be transmitted, and DMRS symbols corresponding to ports / layers not configured / instructed to the UE may not be transmitted.

[0219] For example, a DMRS symbol corresponding to a certain port / layer may be transmitted to a certain UE, and a DMRS symbol corresponding to another port / layer may be transmitted to another UE. In this case, the certain UE does not need to perform reception processing for the DMRS transmitted to the other UE. In other words, the certain UE may ignore the DMRS transmitted to the other UE (the DMRS may not be used for channel estimation).

[0220] The UE may not assume that PDCCH / any other DL signals are mapped to resources in which some DMRSs are not transmitted. Also, the UE may assume that PDCCH / any other DL signals are not mapped to resources in which some DMRSs are not transmitted.

[0221] The UE may assume that the PDCCH is mapped to resources where some DMRS is not transmitted.

[0222] The sequence length of the DMRS may not change compared to when FDM is not used, and the DMRS symbols / REs not transmitted on it may be punctured.

[0223] This configuration is preferable from a particular point of view because it allows for the use of a longer sequence length compared to when the sequence length varies.

[0224] Also, a pseudo-random (PN) sequence may be mapped only to the DMRS symbols / REs that are actually transmitted. In other words, the sequence length of the DMRS may be changed compared to when FDM is not used.

[0225] 10 is a diagram showing an example of PDCCH DMRS to which FDM is applied. In the example shown in FIG. 10, the DMRS resources corresponding to each port (p=2000 / 2001 / 2002) are set to be FDM-based. In this case, the DMRS / PDCCH resources corresponding to p=2001 / 2002 are not transmitted to the UE corresponding to p=2000.

[0226] 11 is a diagram showing another example of PDCCH DMRS to which FDM is applied. In the example shown in FIG. 11, the DMRS resources corresponding to each port (p=2000 / 2001) are configured to be FDM-based. In this case, the DMRS / PDCCH resources corresponding to p=2001 are not transmitted to the UE corresponding to p=2000.

[0227] [TDM] DMRS (PDCCH DMRS) symbols corresponding to different ports / layers may be time division multiplexed (TDM) (in the same time resource / symbol).

[0228] In this case, some DMRS symbols corresponding to different ports / layers may be TDM'd by not transmitting the DMRS.

[0229] For example, only DMRS symbols corresponding to ports / layers configured / instructed to the UE may be transmitted, and DMRS symbols corresponding to ports / layers not configured / instructed to the UE may not be transmitted.

[0230] For example, a DMRS symbol corresponding to a certain port / layer may be transmitted to a certain UE, and a DMRS symbol corresponding to another port / layer may be transmitted to another UE. In this case, the certain UE does not need to perform reception processing for the DMRS transmitted to the other UE. In other words, the certain UE may ignore the DMRS transmitted to the other UE (the DMRS may not be used for channel estimation).

[0231] The UE may not assume that PDCCH / any other DL signals are mapped to resources in which some DMRSs are not transmitted. Also, the UE may assume that PDCCH / any other DL signals are not mapped to resources in which some DMRSs are not transmitted.

[0232] The UE may assume that the PDCCH is mapped to resources where some DMRS is not transmitted.

[0233] The sequence length of the DMRS may not change compared to when TDM is not used, and the DMRS symbols / REs not transmitted on it may be punctured.

[0234] This configuration is preferable from a particular point of view because it allows for the use of a longer sequence length compared to when the sequence length varies.

[0235] Also, a pseudorandom (PN) sequence may be mapped only to the DMRS symbols / REs that are actually transmitted, i.e., the sequence length of the DMRS may vary compared to when TDM is not used.

[0236] 12 is a diagram showing an example of PDCCH DMRS to which TDM is applied. In the example shown in FIG. 12, the DMRS resources corresponding to each port (p=2000 / 2001 / 2002) are set to be TDM. In this case, the DMRS / PDCCH resources corresponding to p=2001 / 2002 are not transmitted to the UE corresponding to p=2000.

[0237] 13 is a diagram showing another example of PDCCH DMRS to which TDM is applied. In the example shown in FIG. 13, the DMRS resources corresponding to each port (p=2000 / 2001) are configured to be TDM. In this case, the DMRS / PDCCH (resources) corresponding to p=2001 are not transmitted to the UE corresponding to p=2000.

[0238] According to the fifth embodiment described above, it is possible to appropriately define PDCCH DMRS using multiple ranks / layers / ports, and it is possible to increase the PDCCH capacity.

[0239] <Supplementary Notes> [Notification of Information to UE (Supplementary Note 1)] In the above-described embodiments, notification of any information to the UE (from a Network (NW) (e.g., a Base Station (BS))) (in other words, reception of any information from the BS by the UE) may be performed using physical layer signaling (e.g., DCI), higher layer signaling (e.g., RRC signaling, MAC CE), a specific signal / channel (e.g., PDCCH, PDSCH, reference signal), or a combination thereof.

[0240] When the notification is performed by a MAC CE, the MAC CE may be identified by including a new Logical Channel ID (LCID) in the MAC subheader, which is not defined in existing standards.

[0241] When the notification is made by DCI, the notification may be made by a specific field of the DCI, a Radio Network Temporary Identifier (RNTI) used to scramble Cyclic Redundancy Check (CRC) bits assigned to the DCI, the format of the DCI, etc.

[0242] Furthermore, notification of any information to the UE in the above embodiments may be performed periodically, semi-persistently, or aperiodically.

[0243] [Notification of Information from UE (Supplementary Note 2)] In the above-described embodiments, notification of any information from the UE (to the NW) (in other words, transmission / report of any information from the UE to the BS) may be performed using physical layer signaling (e.g., UCI), higher layer signaling (e.g., RRC signaling, MAC CE), a specific signal / channel (e.g., PUCCH, PUSCH, PRACH, reference signal), or a combination thereof.

[0244] When the notification is performed by a MAC CE, the MAC CE may be identified by including a new LCID, which is not defined in existing standards, in the MAC subheader.

[0245] If the notification is made by UCI, the notification may be transmitted using PUCCH or PUSCH.

[0246] Furthermore, any information in the above-described embodiments may be notified from the UE periodically, semi-persistently, or aperiodically.

[0247] [Application of Each Embodiment (Supplementary Note 3)] At least one of the above-described embodiments may be applied when a specific condition is met. The specific condition may be specified in a standard or may be notified to a UE / BS using higher layer signaling / physical layer signaling.

[0248] At least one of the above-described embodiments may be applied only to UEs that have reported or support a particular UE capability.

[0249] The specific UE capability may indicate at least one of the following: Supporting specific processing / operation / control / information for at least one of the above embodiments (e.g., PDCCH reception using multi-layers / ports / ranks, PDCCH reception in MU-MIMO). Supporting reception of PDCCH DMRS using FD-OCC / TD-OCC / FDM / TDM. Number of layers / ports / ranks of PDCCH / DMRS supported.

[0250] Furthermore, the above-mentioned specific UE capability may be a capability that is applied across all frequencies (commonly regardless of frequency), or may be a capability for each frequency (e.g., one or a combination of a cell, a band, a band combination, a BWP, a component carrier, etc.), or may be a capability for each frequency range (e.g., Frequency Range 1 (FR1), FR2, FR3, FR4, FR5, FR2-1, FR2-2), or may be a capability for each subcarrier spacing (SubCarrier Spacing (SCS)), or may be a capability for each Feature Set (FS) or Feature Set Per Component-carrier (FSPC).

[0251] Furthermore, the specific UE capability may be a capability that is applied to all duplexing methods (commonly regardless of the duplexing method), or may be a capability for each duplexing method (e.g., Time Division Duplex (TDD) or Frequency Division Duplex (FDD)).

[0252] Furthermore, at least one of the above-described embodiments may be applied when the UE configures / activates / triggers specific information related to the above-described embodiments (or performs the operations of the above-described embodiments) through higher layer signaling / physical layer signaling. For example, the specific information may be information indicating that reception of PDCCH using multi-layer / port / rank is enabled, any RRC parameter for a specific release (e.g., Rel. 18 / 19), etc.

[0253] If the UE does not support at least one of the specific UE capabilities or is not configured with the specific information, the UE may apply, for example, Rel. 15 / 16 behavior.

[0254] (Supplementary Note A) The following inventions are added to one embodiment of the present disclosure. [Supplementary Note A-1] A terminal having: a control unit that determines a control channel element (CCE) index based on a first derivation method for CCE indices corresponding to candidates for a physical downlink control channel (PDCCH) using multiple layers, the CCE indices being different from the first derivation method and a second derivation method for CCE indices corresponding to candidates for a PDCCH using one layer; and a receiving unit that monitors the PDCCH using multiple layers based on the CCE indices. [Supplementary Note A-2] The terminal according to Supplementary Note A-1, wherein a first parameter based on a slot number in the first derivation method is different from a second parameter based on a slot number in the second derivation method. [Supplementary Note A-3] The terminal according to Supplementary Note A-1 or Supplementary Note A-2, wherein the first parameter based on a slot number in the first derivation method is determined based on a specific initial value, and the specific initial value is different from a value of a specific Radio Network Temporary Identifier (RNTI). [Supplementary Note A-4] The terminal according to any of Supplementary Note A-1 to Supplementary Note A-3, wherein the first parameter based on a slot number in the first derivation method is based on a value of a specific Radio Network Temporary Identifier (RNTI), and the control unit determines to update the value of the specific RNTI based on specific instruction information.

[0255] (Supplementary Note B) The following inventions are added to one embodiment of the present disclosure. [Supplementary Note B-1] A terminal comprising: a control unit that determines a specific antenna port orthogonal to a first antenna port used to receive a physical downlink control channel (PDCCH) of a plurality of layers; and a receiving unit that receives the PDCCH of a plurality of layers on the assumption that the specific antenna port is not associated with a physical downlink shared channel (PDSCH) and a PDCCH intended for a specific other terminal. [Supplementary Note B-2] The terminal according to Supplementary Note B-1, wherein the specific antenna port is an antenna port other than the first antenna port that is orthogonal to the first antenna port. [Supplementary Note B-3] The terminal according to Supplementary Note B-1 or Supplementary Note B-2, wherein the specific antenna port is an antenna port orthogonal to the first antenna port, and wherein frequency division multiplexing, time division multiplexing, a frequency domain orthogonal cover code, a time domain orthogonal cover code, or a frequency domain and time domain orthogonal cover code is used for a demodulation reference signal of a PDCCH. [Supplementary Note B-4] The terminal according to any one of Supplementary Note B-1 to Supplementary Note B-3, wherein the specific other terminal is another terminal that can receive a PDCCH using only one layer.

[0256] (Wireless Communication System) The configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof.

[0257] 14 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 (which may be simply referred to as system 1) may be a system that realizes communication using Long Term Evolution (LTE) or 5th generation mobile communication system New Radio (5G NR) specified by the Third Generation Partnership Project (3GPP).

[0258] The wireless communication system 1 may also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

[0259] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (Master Node (MN)), and the NR base station (gNB) is the secondary node (Secondary Node (SN)). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0260] The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity in which both the MN and SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

[0261] The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with a relatively wide coverage, and base stations 12 (12a-12c) that are located within the macrocell C1 and form small cells C2 that are smaller than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The locations and numbers of the cells and user terminals 20 are not limited to the embodiment shown in the figure. Hereinafter, when there is no need to distinguish between the base stations 11 and 12, they will be collectively referred to as base station 10.

[0262] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CCs) and dual connectivity (DC).

[0263] Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may be included in FR1, and the small cell C2 may be included in FR2. For example, FR1 may be a frequency band of 6 GHz or less (sub-6 GHz), and FR2 may be a frequency band higher than 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may correspond to a higher frequency band than FR2.

[0264] Furthermore, the user terminal 20 may perform communication using at least one of time division duplex (TDD) and frequency division duplex (FDD) in each CC.

[0265] The multiple base stations 10 may be connected by wire (e.g., optical fiber compliant with the Common Public Radio Interface (CPRI), an X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication is used as a backhaul between the base stations 11 and 12, the base station 11 corresponding to the upper station may be called an Integrated Access Backhaul (IAB) donor, and the base station 12 corresponding to the relay station (relay) may be called an IAB node.

[0266] The base station 10 may be connected to the core network 30 directly or via another base station 10. The core network 30 may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), and the like.

[0267] The core network 30 may include network functions (Network Functions (NF)) such as a User Plane Function (UPF), an Access and Mobility management Function (AMF), a Session Management Function (SMF), a Unified Data Management (UDM), an Application Function (AF), a Data Network (DN), a Location Management Function (LMF), and Operation, Administration and Maintenance (Management) (OAM). A single network node may provide multiple functions. Communication with an external network (e.g., the Internet) may also be performed via the DN.

[0268] The user terminal 20 may be a terminal that supports at least one of communication methods such as LTE, LTE-A, and 5G.

[0269] An Orthogonal Frequency Division Multiplexing (OFDM)-based radio access scheme may be used in the wireless communication system 1. For example, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), or the like may be used in at least one of the downlink (DL) and uplink (UL).

[0270] The radio access scheme may also be called a waveform. Note that in the wireless communication system 1, other radio access schemes (e.g., other single-carrier transmission schemes, other multi-carrier transmission schemes) may be used as the UL and DL radio access schemes.

[0271] In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as the downlink channel.

[0272] Furthermore, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), or the like may be used as an uplink channel.

[0273] The PDSCH transmits user data, higher layer control information, a System Information Block (SIB), etc. The PUSCH may transmit user data, higher layer control information, etc. Furthermore, the PBCH may transmit a Master Information Block (MIB).

[0274] Lower layer control information may be transmitted by the PDCCH. The lower layer control information may include, for example, Downlink Control Information (DCI) including scheduling information for at least one of the PDSCH and the PUSCH.

[0275] Note that the DCI for scheduling the PDSCH may be referred to as a DL assignment, a DL DCI, etc., and the DCI for scheduling the PUSCH may be referred to as a UL grant, a UL DCI, etc. Note that the PDSCH may be replaced with DL data, and the PUSCH may be replaced with UL data.

[0276] A control resource set (CORESET) and a search space may be used to detect the PDCCH. The CORESET corresponds to resources for searching for DCI. The search space corresponds to a search region and a search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor the CORESET associated with a certain search space based on the search space configuration.

[0277] One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be referred to as a search space set. Note that the terms "search space," "search space set," "search space configuration," "search space set configuration," "CORESET," "CORESET configuration," and the like in the present disclosure may be read interchangeably.

[0278] The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), delivery confirmation information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK / NACK, etc.), and scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

[0279] In the present disclosure, downlink, uplink, etc. may be expressed without adding "link." Also, various channels may be expressed without adding "Physical" to the beginning.

[0280] In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, as the DL-RS, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted.

[0281] The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including an SS (PSS, SSS) and a PBCH (and a DMRS for the PBCH) may be referred to as an SS / PBCH block, an SS Block (SSB), or the like. Note that the SS, SSB, and the like may also be referred to as a reference signal.

[0282] Furthermore, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), or the like may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may also be called a user equipment-specific reference signal (UE-specific reference signal).

[0283] 15 is a diagram showing an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that the base station may include one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140.

[0284] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the base station 10 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0285] The control unit 110 performs overall control of the base station 10. The control unit 110 can be configured from a controller, a control circuit, and the like that are explained based on common understanding in the technical field to which the present disclosure relates.

[0286] The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 120. The control unit 110 may perform call processing (setting up, releasing, etc.) of communication channels, status management of the base station 10, management of radio resources, etc.

[0287] The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0288] The transmitting / receiving unit 120 may be configured as an integrated transmitting / receiving unit, or may be configured from a transmitting unit and a receiving unit. The transmitting unit may be configured from a transmission processing unit 1211 and an RF unit 122. The receiving unit may be configured from a reception processing unit 1212, the RF unit 122, and a measurement unit 123.

[0289] The transmitting and receiving antenna 130 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

[0290] The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

[0291] The transceiver 120 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0292] The transmitter / receiver unit 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

[0293] The transmitter / receiver unit 120 (transmission processing unit 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0294] The transceiver unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 130.

[0295] On the other hand, the transceiver unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 130.

[0296] The transceiver 120 (reception processing unit 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, thereby acquiring user data, etc.

[0297] The transceiver 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

[0298] The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30 (e.g., network nodes that provide NF), other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

[0299] The transmitting section and receiving section of the base station 10 in the present disclosure may be configured by at least one of the transmitting / receiving section 120, the transmitting / receiving antenna 130, and the transmission path interface 140.

[0300] The control unit 110 may indicate the control channel element (CCE) index using a first derivation method for CCE indices corresponding to candidates for a physical downlink control channel (PDCCH) using multiple layers. The first derivation method may be different from a second derivation method for CCE indices corresponding to candidates for a PDCCH using one layer. The transceiver unit 120 may transmit the PDCCH using multiple layers using the CCE indices (first embodiment).

[0301] The control unit 110 may specify a specific antenna port orthogonal to a first antenna port used to receive physical downlink control channels (PDCCHs) of multiple layers, and the transceiver unit 120 may transmit the PDCCHs of the multiple layers without associating the specific antenna port with a physical downlink shared channel (PDSCH) and a PDCCH intended for a specific other terminal (fourth embodiment).

[0302] (User Terminal) Fig. 16 is a diagram showing an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transceiver antenna 230. Note that the user terminal 20 may include one or more of each of the control unit 210, the transceiver unit 220, and the transceiver antenna 230.

[0303] In this example, the functional blocks of the characteristic parts of the present embodiment are mainly shown, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

[0304] The control unit 210 performs overall control of the user terminal 20. The control unit 210 can be configured from a controller, a control circuit, etc., which are described based on common understanding in the technical field to which the present disclosure relates.

[0305] The control unit 210 may control signal generation, mapping, etc. The control unit 210 may control transmission and reception, measurement, etc. using the transceiver unit 220 and the transceiver antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals and transfer them to the transceiver unit 220.

[0306] The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be configured with a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

[0307] The transmitting / receiving unit 220 may be configured as an integrated transmitting / receiving unit, or may be composed of a transmitting unit and a receiving unit. The transmitting unit may be composed of a transmission processing unit 2211 and an RF unit 222. The receiving unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

[0308] The transmitting / receiving antenna 230 can be configured from an antenna described based on common understanding in the technical field to which the present disclosure relates, such as an array antenna.

[0309] The transceiver 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

[0310] The transceiver unit 220 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), or the like.

[0311] The transceiver unit 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

[0312] The transmitter / receiver unit 220 (transmission processing unit 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

[0313] Whether or not to apply DFT processing may be based on the setting of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the transmission processing to transmit the channel using a DFT-s-OFDM waveform, and if not, it may not be necessary to perform DFT processing as the transmission processing.

[0314] The transceiver unit 220 (RF unit 222) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 230.

[0315] On the other hand, the transceiver unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 230.

[0316] The transceiver unit 220 (reception processing unit 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data, etc.

[0317] The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

[0318] The measurement unit 223 may derive channel measurements for CSI calculation based on the channel measurement resources. The channel measurement resources may be, for example, non-zero power (NZP) CSI-RS resources. The measurement unit 223 may also derive interference measurements for CSI calculation based on the interference measurement resources. The interference measurement resources may be at least one of an NZP CSI-RS resource for interference measurement, a CSI-Interference Measurement (IM) resource, etc. Note that CSI-IM may be referred to as CSI-Interference Management (IM) or may be interchangeably read as Zero Power (ZP) CSI-RS. Note that in the present disclosure, CSI-RS, NZP CSI-RS, ZP CSI-RS, CSI-IM, CSI-SSB, etc. may be interchangeably read as interchangeable.

[0319] The transmitting unit and receiving unit of the user terminal 20 in the present disclosure may be configured by at least one of the transmitting / receiving unit 220 and the transmitting / receiving antenna 230.

[0320] The control unit 210 may determine the control channel element (CCE) index based on a first derivation method for CCE indices corresponding to candidates for a physical downlink control channel (PDCCH) using multiple layers. The first derivation method may be different from a second derivation method for CCE indices corresponding to candidates for a PDCCH using one layer. The transceiver unit 220 may monitor the PDCCH using multiple layers based on the CCE indices.

[0321] The first parameter based on the slot number in the first derivation method may be different from the second parameter based on the slot number in the second derivation method (first embodiment).

[0322] The first parameter based on the slot number in the first derivation method may be determined based on a specific initial value, which may be different from a specific Radio Network Temporary Identifier (RNTI) value (second embodiment).

[0323] The first parameter based on the slot number in the first derivation method may be based on a value of a specific Radio Network Temporary Identifier (RNTI). The control unit 210 may determine whether to update the value of the specific RNTI based on specific instruction information (third embodiment).

[0324] The control unit 210 may determine a specific antenna port that is orthogonal to a first antenna port used to receive Physical Downlink Control Channels (PDCCHs) of multiple layers, and the transceiver unit 220 may receive the PDCCHs of multiple layers, assuming that the specific antenna port is not associated with Physical Downlink Shared Channels (PDSCHs) and PDCCHs for specific other terminals (fourth embodiment).

[0325] The specific antenna port may be an antenna port other than the first antenna port that is orthogonal to the first antenna port (fourth embodiment).

[0326] The specific antenna port may be an antenna port orthogonal to the first antenna port, and frequency division multiplexing, time division multiplexing, frequency domain orthogonal cover code, time domain orthogonal cover code, or frequency domain and time domain orthogonal cover code is used for the demodulation reference signal of the PDCCH (fourth embodiment).

[0327] The specific other terminal may be another terminal that can receive the PDCCH using only one layer (fourth embodiment).

[0328] (Hardware Configuration) Note that the block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may be realized by combining software with the single device or the multiple devices.

[0329] Here, the functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission may be called a transmitting unit, transmitter, etc. As described above, the implementation method of each is not particularly limited.

[0330] For example, a base station, a user terminal, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 17 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. The above-described base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0331] In the present disclosure, the terms apparatus, circuit, device, section, unit, etc. may be used interchangeably. The hardware configurations of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the drawings, or may be configured to exclude some of the devices.

[0332] For example, although only one processor 1001 is shown, there may be multiple processors. Furthermore, processing may be performed by one processor, or processing may be performed by two or more processors simultaneously, serially, or in other ways. Furthermore, processor 1001 may be implemented by one or more chips.

[0333] Each function in the base station 10 and the user terminal 20 is realized, for example, by loading specified software (programs) onto hardware such as a processor 1001 and a memory 1002, causing the processor 1001 to perform calculations, control communication via the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0334] The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, at least a part of the above-mentioned control unit 110 (210), transceiver unit 120 (220), etc. may be realized by the processor 1001.

[0335] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002 and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 110 (210) may be implemented by a control program stored in the memory 1002 and running on the processor 1001, and the other functional blocks may be implemented in a similar manner.

[0336] The memory 1002 is a computer-readable recording medium and may be configured by at least one of, for example, Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EEPROM (EEPROM), Random Access Memory (RAM), or other suitable storage medium. The memory 1002 may also be referred to as a register, cache, main memory, etc. The memory 1002 may store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to an embodiment of the present disclosure.

[0337] Storage 1003 is a computer-readable recording medium and may be composed of at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disc (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disc, a Blu-ray disc), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, a stick, a key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as an auxiliary storage device.

[0338] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the above-mentioned transmission / reception unit 120 (220), transmission / reception antenna 130 (230), etc. may be realized by the communication device 1004. The transmission / reception unit 120 (220) may be implemented as a transmission unit 120a (220a) and a reception unit 120b (220b) that are physically or logically separated.

[0339] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, a light emitting diode (LED) lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0340] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0341] Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using this hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0342] (Modifications) Note that terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applicable standard. A component carrier (CC) may also be called a cell, frequency carrier, carrier frequency, etc.

[0343] A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0344] Here, the numerology may be a communication parameter applied to at least one of transmission and reception of a signal or channel, and may indicate at least one of, for example, Subcarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), number of symbols per TTI, radio frame structure, specific filtering performed by a transceiver in the frequency domain, and specific windowing performed by a transceiver in the time domain.

[0345] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol) in the time domain. A slot may also be a time unit based on numerology.

[0346] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

[0347] A radio frame, a subframe, a slot, a minislot, and a symbol all represent time units for transmitting signals. The radio frame, the subframe, the slot, the minislot, and the symbol may be referred to by other names corresponding to the radio frame, the subframe, the slot, the minislot, and the symbol. Note that the time units such as a frame, a subframe, a slot, a minislot, and a symbol in the present disclosure may be interchangeable.

[0348] For example, one subframe may be referred to as a TTI, or multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc. instead of a subframe.

[0349] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

[0350] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0351] When one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0352] A TTI having a time length of 1 ms may be called a regular TTI (TTI in 3GPP Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0353] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and greater than or equal to 1 ms.

[0354] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may be determined based on numerology.

[0355] In addition, an RB may include one or more symbols in the time domain and may have a length of one slot, one minislot, one subframe, or one TTI, each of which may be composed of one or more resource blocks.

[0356] In addition, one or more RBs may be referred to as a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0357] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0358] A Bandwidth Part (BWP), which may also be referred to as a partial bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0359] The BWP may include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). One or more BWPs may be configured for a UE within one carrier.

[0360] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0361] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0362] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by a predetermined index.

[0363] The names used for parameters and the like in this disclosure are not intended to be limiting in any way. Furthermore, the mathematical expressions and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0364] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0365] Furthermore, information, signals, etc. may be output from a higher layer to a lower layer and / or from a lower layer to a higher layer. Information, signals, etc. may be input / output via multiple network nodes.

[0366] Input and output information, signals, etc. may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

[0367] The notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information in the present disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0368] Note that the physical layer signaling may be referred to as Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. Furthermore, the RRC signaling may be referred to as an RRC message, such as an RRC Connection Setup message or an RRC Connection Reconfiguration message. Furthermore, the MAC signaling may be notified using, for example, a MAC Control Element (CE).

[0369] Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may be made implicitly (e.g., by not notifying the specified information or by notifying other information).

[0370] The determination may be made by a value represented by one bit (0 or 1), by a Boolean value represented by true or false, or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0371] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0372] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), these wired and / or wireless technologies are included within the definition of transmission media.

[0373] As used in this disclosure, the terms "system" and "network" may be used interchangeably. A "network" may refer to devices included in the network (e.g., base stations).

[0374] 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," "layer," "number of layers," "rank," "resource," "resource set," "beam," "beam width," "beam angle," "antenna," "antenna element," "panel," "UE panel," "transmitting entity," "receiving entity," etc. may be used interchangeably.

[0375] In the present disclosure, the term "antenna port" may be interchangeably read as an antenna port for any signal / channel (e.g., a demodulation reference signal (DMRS) port). In the present disclosure, the term "resource" may be interchangeably read as a resource for any signal / channel (e.g., a reference signal resource, an SRS resource, etc.). The resource may include time / frequency / code / space / power resources. Furthermore, the spatial domain transmission filter may include at least one of a spatial domain transmission filter and a spatial domain reception filter.

[0376] The group may include, for example, at least one of a spatial relationship group, a Code Division Multiplexing (CDM) group, a Reference Signal (RS) group, a Control Resource Set (CORESET) group, a PUCCH group, an antenna port group (e.g., a DMRS port group), a layer group, a resource group, a beam group, an antenna group, a panel group, and the like.

[0377] In addition, in the present disclosure, beam, SRS Resource Indicator (SRI), CORESET, CORESET pool, PDSCH, PUSCH, codeword (CW), transport block (TB), RS, etc. may be read as interchangeable terms.

[0378] In addition, in the present disclosure, the terms TCI state, downlink TCI state (DL TCI state), uplink TCI state (UL TCI state), unified TCI state, common TCI state, joint TCI state, etc. may be read interchangeably.

[0379] Furthermore, in the present disclosure, terms such as "QCL," "QCL assumption," "QCL relationship," "QCL type information," "QCL property / properties," "specific QCL type (e.g., Type A, Type D) property," and "specific QCL type (e.g., Type A, Type D)" may be interchangeable.

[0380] In the present disclosure, terms such as index, identifier (ID), indicator, indication, and resource ID may be interchangeable. In the present disclosure, terms such as sequence, list, set, group, cluster, and subset may be interchangeable.

[0381] Furthermore, the spatial relationship information identifier (ID) (TCI state ID) and the spatial relationship information (TCI state) may be interchangeable. The "spatial relationship information (TCI state)" may be interchangeable with "set of spatial relationship information (TCI state)", "one or more pieces of spatial relationship information", etc. The TCI state and the TCI may be interchangeable. The spatial relationship information and the spatial relationship may be interchangeable.

[0382] In the present disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "access point," "transmission point (TP)," "reception point (RP)," "transmission / reception point (TRP)," "panel," "cell," "sector," "cell group," "carrier," "component carrier," etc. may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, picocell, etc.

[0383] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be partitioned into multiple smaller areas, and each smaller area can be provided with communication service by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication service within that coverage.

[0384] In the present disclosure, a base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control / operate based on the information.

[0385] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0386] A mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0387] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a wireless communication device, etc. Note that at least one of the base station and the mobile station may be a device mounted on a moving object, the moving object itself, etc.

[0388] The mobile body is a movable object that can move at any speed and naturally includes cases where the mobile body is stationary. Examples of the mobile body include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones, multicopters, quadcopters, balloons, and objects mounted thereon. The mobile body may also be a mobile body that moves autonomously based on an operation command.

[0389] The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Note that at least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0390] 18 is a diagram showing an example of a vehicle according to an embodiment. The vehicle 40 includes a drive unit 41, a steering unit 42, an accelerator pedal 43, a brake pedal 44, a shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, an electronic control unit 49, various sensors (including a current sensor 50, an RPM sensor 51, an air pressure sensor 52, a vehicle speed sensor 53, an acceleration sensor 54, an accelerator pedal sensor 55, a brake pedal sensor 56, a shift lever sensor 57, and an object detection sensor 58), an information service unit 59, and a communication module 60.

[0391] The drive unit 41 is configured with at least one of an engine, a motor, and a hybrid of an engine and a motor, for example. The steering unit 42 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels 46 and the rear wheels 47 based on the operation of the steering wheel operated by a user.

[0392] The electronic control unit 49 is composed of a microprocessor 61, memory (ROM, RAM) 62, and a communication port (for example, an input / output (IO) port) 63. Signals are input to the electronic control unit 49 from various sensors 50-58 provided in the vehicle. The electronic control unit 49 may also be called an Electronic Control Unit (ECU).

[0393] The signals from the various sensors 50-58 include a current signal from a current sensor 50 that senses the current of the motor, a rotation speed signal of the front wheels 46 / rear wheels 47 obtained by a rotation speed sensor 51, an air pressure signal of the front wheels 46 / rear wheels 47 obtained by an air pressure sensor 52, a vehicle speed signal obtained by a vehicle speed sensor 53, an acceleration signal obtained by an acceleration sensor 54, a depression amount signal of the accelerator pedal 43 obtained by an accelerator pedal sensor 55, a depression amount signal of the brake pedal 44 obtained by a brake pedal sensor 56, an operation signal of the shift lever 45 obtained by a shift lever sensor 57, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 58.

[0394] The information service unit 59 is composed of various devices, such as a car navigation system, an audio system, speakers, a display, a television, and a radio, for providing (outputting) various information such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 59 uses information acquired from external devices via the communication module 60 or the like to provide various information / services (e.g., multimedia information / multimedia services) to the occupants of the vehicle 40.

[0395] The information service unit 59 may include input devices (e.g., keyboards, mice, microphones, switches, buttons, sensors, touch panels, etc.) that accept input from the outside, and may also include output devices (e.g., displays, speakers, LED lamps, touch panels, etc.) that output to the outside.

[0396] The driving assistance system unit 64 includes various devices for providing functions to prevent accidents and reduce the driver's driving burden, such as millimeter-wave radar, Light Detection and Ranging (LiDAR), cameras, positioning locators (e.g., Global Navigation Satellite System (GNSS)), map information (e.g., High Definition (HD) maps, Autonomous Vehicle (AV) maps), gyro systems (e.g., Inertial Measurement Units (IMUs), Inertial Navigation Systems (INSs)), artificial intelligence (AI) chips, and AI processors, as well as one or more ECUs that control these devices. The driving assistance system unit 64 also transmits and receives various information via the communication module 60 to realize driving assistance functions or autonomous driving functions.

[0397] The communication module 60 can communicate with the microprocessor 61 and components of the vehicle 40 via the communication port 63. For example, the communication module 60 transmits and receives data (information) via the communication port 63 to and from the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, the microprocessor 61 and memory (ROM, RAM) 62 in the electronic control unit 49, and the various sensors 50-58, which are provided in the vehicle 40.

[0398] The communication module 60 is a communication device that can be controlled by the microprocessor 61 of the electronic control unit 49 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 60 may be located either inside or outside the electronic control unit 49. The external device may be, for example, the base station 10 or the user terminal 20 described above. Furthermore, the communication module 60 may be, for example, at least one of the base station 10 and the user terminal 20 described above (or may function as at least one of the base station 10 and the user terminal 20).

[0399] The communication module 60 may transmit at least one of signals from the above-mentioned various sensors 50-58 input to the electronic control unit 49, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 59 to an external device via wireless communication. The electronic control unit 49, the various sensors 50-58, the information service unit 59, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 60 may include information based on the above-mentioned input.

[0400] The communication module 60 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from an external device and displays it on an information service unit 59 provided in the vehicle. The information service unit 59 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH received by the communication module 60 (or data / information decoded from the PDSCH)).

[0401] Furthermore, the communication module 60 stores various information received from external devices in a memory 62 that can be used by the microprocessor 61. Based on the information stored in the memory 62, the microprocessor 61 may control the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, various sensors 50-58, and the like provided in the vehicle 40.

[0402] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple user terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the user terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "sidelink"). For example, terms such as an uplink channel and a downlink channel may be read as a sidelink channel.

[0403] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station 10 may be configured to have the functions of the user terminal 20 described above.

[0404] In the present disclosure, an operation described as being performed by a base station may be performed by its upper node in some cases. It is apparent that in a network including one or more network nodes having a base station, various operations performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME), a Serving-Gateway (S-GW), etc.), or a combination thereof.

[0405] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, the order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0406] Each aspect / embodiment described in the present disclosure may be a technology other than Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG (x is, for example, an integer or decimal number)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (Wi-Fi (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 (WiMAX (registered trademark)), IEEE 802.30 (WiMAX (registered trademark)), IEEE 802.31 (Wi-Fi (registered trademark)), IEEE 802.32 (WiMAX (registered trademark)), IEEE 802.33 (WiMAX (registered trademark)), IEEE 802. The present invention may be applied to systems that use IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable wireless communication methods, or to next-generation systems that are expanded, modified, created, or defined based on these. Furthermore, the present invention may be applied to a combination of multiple systems (e.g., a combination of LTE or LTE-A and 5G).

[0407] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0408] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0409] The term "determining" as used in this disclosure may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., looking up in a table, database, or another data structure), ascertaining, etc.

[0410] Additionally, "determining" may be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), etc.

[0411] Furthermore, "determination" may be considered to be "determining" resolving, selecting, choosing, establishing, comparing, etc. In other words, "determination" may be considered to be "determining" some kind of action. In the present disclosure, "determination" may be read interchangeably with the above-mentioned actions.

[0412] Furthermore, in this disclosure, "determine / determining" may be interchangeably read as "assume / assuming," "expect / expecting," "consider / considering," etc. Furthermore, in this disclosure, "does not expect to do..." may be interchangeably read as "assumes not to do...."

[0413] In the present disclosure, "expect" may be interchangeably read as "be expected." For example, "expect(s) ..." ("..." may be expressed, for example, as a that clause, a to-infinitive, etc.) may be interchangeably read as "be expected ...." "does not expect ..." may be interchangeably read as "be not expected ...." Furthermore, "An apparatus A is not expected ..." may be interchangeably read as "an apparatus B other than apparatus A does not expect ... from apparatus A" (e.g., if apparatus A is a UE, apparatus B may be a base station).

[0414] The "maximum transmit power" in this disclosure may mean the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0415] As used in this disclosure, the terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access."

[0416] In this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, etc., as some non-limiting and non-exhaustive examples.

[0417] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0418] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0419] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0420] In the present disclosure, terms such as "less than or equal to," "less than," "greater than," "more than," "equal to," etc. may be interchangeable. Furthermore, in the present disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "fast," "slow," "wide," "narrow," etc. may be interchangeable, not limited to the positive, comparative, and superlative. Furthermore, in the present disclosure, terms meaning "good," "bad," "big," "small," "high," "low," "fast," "slow," "wide," "narrow," etc. may be interchangeable, not limited to the positive, comparative, and superlative, as expressions with "i-th" (i is an arbitrary integer) attached (for example, "highest" may be interchangeable with "i-th highest").

[0421] In this disclosure, the terms "of," "for," "regarding," "related to," "associated with," etc. may be read interchangeably.

[0422] In the present disclosure, terms such as "when A, B," "if A, (then) B," "B upon A," "B in response to A," "B based on A," "B during / while A," "B before A," "B at (the same time as) / on A," "B after A," "B since A," and "B until A" may be interchangeable. Note that A, B, and the like herein may be replaced with appropriate expressions such as nouns, gerunds, and regular sentences, depending on the context. Note that the time difference between A and B may be approximately zero (immediately after or immediately before). A time offset may also be applied to the time at which A occurs. For example, "A" may be interchangeable with "before / after a time offset at which A occurs." The time offset (eg, one or more symbols / slots) may be predefined or may be specified by the UE based on signaled information.

[0423] In the present disclosure, timing, time, duration, time instance, any time unit (e.g., slot, subslot, symbol, subframe), period, occasion, resource, etc. may be read interchangeably.

[0424] Although the invention according to the present disclosure has been described in detail above, it is clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The description of the present disclosure is for illustrative purposes only and does not impose any limiting meaning on the invention according to the present disclosure.

Claims

1. A terminal having a control unit that determines a control channel element (CCE) index based on a first derivation method for a CCE index corresponding to a candidate for a physical downlink control channel (PDCCH) using multiple layers, the CCE index being different from the first derivation method and a second derivation method for a CCE index corresponding to a candidate for a PDCCH using one layer; and a receiving unit that monitors the PDCCH using multiple layers based on the CCE index.

2. The terminal of claim 1, wherein a first parameter based on a slot number in the first derivation method is different from a second parameter based on a slot number in the second derivation method.

3. The terminal according to claim 1, wherein the first parameter based on the slot number in the first derivation method is determined based on a specific initial value, and the specific initial value is different from a value of a specific Radio Network Temporary Identifier (RNTI).

4. The terminal according to claim 1, wherein the first parameter based on the slot number in the first derivation method is based on a value of a specific Radio Network Temporary Identifier (RNTI), and the control unit determines whether to update the value of the specific RNTI based on specific instruction information.

5. A wireless communication method for a terminal, comprising: a step of determining a control channel element (CCE) index corresponding to a candidate for a physical downlink control channel (PDCCH) using multiple layers based on a first derivation method for CCE indexes corresponding to candidates for a PDCCH using one layer, the first derivation method being different from a second derivation method for CCE indexes corresponding to candidates for a PDCCH using one layer; and a step of monitoring the PDCCH using multiple layers based on the CCE index.

6. A base station having: a control unit that indicates a control channel element (CCE) index using a first derivation method for a CCE index corresponding to a candidate for a physical downlink control channel (PDCCH) using multiple layers, the CCE index being different from the first derivation method and a second derivation method for a CCE index corresponding to a candidate for a PDCCH using one layer; and a transmission unit that transmits the PDCCH using the multiple layers using the CCE index.