WO2023026975A1 - Terminal, wireless communication system, and wireless communication method - Google Patents

Abstract

This terminal comprises: a transmission unit that transmits feedback to be used in selecting a modulation scheme to be used in a downlink channel; and a control unit that performs specific control on transmission of the feedback, on the basis of the priority of the feedback, when the feedback and channel state information overlap in time.

Description

Terminal, wireless communication system and wireless communication method

The present disclosure relates to a terminal, base station, and wireless communication method that perform wireless communication, and in particular, to a terminal, wireless communication system, and wireless communication method that transmit feedback used in modulation scheme selection.

The 3rd Generation Partnership Project (3GPP) has specified the 5th generation mobile communication system (also called 5G, New Radio (NR) or Next Generation (NG)), and the next generation specification called Beyond 5G, 5G Evolution or 6G We are also proceeding with

In Release 17 of 3GPP, the user equipment ) to the network is being studied (for example, Non-Patent Document 1). Specifically, support for delta-CQI (Channel Quality Indicator)/MCS was agreed upon as feedback.

One aspect of the present disclosure is a terminal, a transmission unit that transmits feedback used in selecting a modulation scheme to be used in a downlink channel, and when the feedback and channel state information overlap in time, the feedback is and a control unit that executes specific control regarding transmission of the feedback based on the order of priority.

One aspect of the present disclosure is a wireless communication system, comprising a terminal and a base station, wherein the terminal transmits feedback used in selecting a modulation scheme to be used in a downlink channel; and a control unit that performs specific control on transmission of the feedback based on the priority of the feedback when the information overlaps in time.

One aspect of the present disclosure is a wireless communication method, comprising: transmitting feedback used in selecting a modulation scheme to be used in a downlink channel; and performing specific control regarding the transmission of the feedback based on the priority of the.

FIG. 1 is an overall schematic configuration diagram of a radio communication system 10. As shown in FIG. FIG. 2 is a diagram illustrating frequency ranges used in wireless communication system 10. As shown in FIG. FIG. 3 is a diagram showing a configuration example of radio frames, subframes and slots used in the radio communication system 10. As shown in FIG. FIG. 4 is a functional block configuration diagram of UE200. FIG. 5 is a functional block configuration diagram of gNB100. FIG. 6 is a diagram for explaining the order of priority. FIG. 7 is a diagram showing an example of the hardware configuration of gNB100 and UE200.

Hereinafter, embodiments will be described based on the drawings. Note that the same or similar reference numerals are given to the same functions and configurations, and the description thereof will be omitted as appropriate.

[Embodiment]
(1) Overall Schematic Configuration of Radio Communication System FIG. 1 is an overall schematic configuration diagram of a radio communication system 10 according to an embodiment. The radio communication system 10 is a radio communication system according to 5G New Radio (NR), and includes a Next Generation-Radio Access Network 20 (hereinafter NG-RAN 20 and a terminal 200 (hereinafter UE 200).

Note that the wireless communication system 10 may be a wireless communication system according to a system called Beyond 5G, 5G Evolution, or 6G.

NG-RAN 20 includes a radio base station 100A (hereinafter gNB100A) and a radio base station 100B (hereinafter gNB100B). Note that the specific configuration of the radio communication system 10 including the number of gNBs and UEs is not limited to the example shown in FIG.

NG-RAN 20 actually includes multiple NG-RAN Nodes, specifically gNBs (or ng-eNBs), and is connected to a 5G-compliant core network (5GC, not shown). Note that NG-RAN 20 and 5GC may simply be referred to as a "network".

gNB100A and gNB100B are 5G-compliant radio base stations and perform 5G-compliant radio communication with UE200. gNB100A, gNB100B and UE200 generate BM beams with higher directivity by controlling radio signals transmitted from multiple antenna elements Massive MIMO (Multiple-Input Multiple-Output), multiple component carriers (CC ), and dual connectivity (DC) that simultaneously communicates with two or more transport blocks between the UE and each of the two NG-RAN Nodes.

Also, the wireless communication system 10 supports multiple frequency ranges (FR). FIG. 2 shows the frequency ranges used in wireless communication system 10. As shown in FIG.

As shown in FIG. 2, the wireless communication system 10 supports FR1 and FR2. The frequency bands of each FR are as follows.

・FR1: 410MHz to 7.125GHz
・FR2: 24.25 GHz to 52.6 GHz
In FR1, a Sub-Carrier Spacing (SCS) of 15, 30 or 60 kHz may be used and a bandwidth (BW) of 5-100 MHz may be used. FR2 is higher frequency than FR1 and may use an SCS of 60 or 120 kHz (240 kHz may be included) and a bandwidth (BW) of 50-400 MHz.

It should be noted that SCS may be interpreted as numerology. numerology is defined in 3GPP TS38.300 and corresponds to one subcarrier spacing in the frequency domain.

Furthermore, the wireless communication system 10 also supports frequency bands higher than the FR2 frequency band. Specifically, the wireless communication system 10 supports frequency bands above 52.6 GHz and up to 71 GHz or 114.25 GHz. Such high frequency bands may be conveniently referred to as "FR2x".

Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM)/ Discrete Fourier Transform - Spread (DFT-S-OFDM) may be applied.

FIG. 3 shows a configuration example of radio frames, subframes and slots used in the radio communication system 10. FIG.

As shown in FIG. 3, one slot consists of 14 symbols, and the larger (wider) the SCS, the shorter the symbol period (and slot period). The SCS is not limited to the intervals (frequencies) shown in FIG. For example, 480 kHz, 960 kHz, etc. may be used.

Also, the number of symbols forming one slot does not necessarily have to be 14 symbols (eg, 28 symbols, 56 symbols). Furthermore, the number of slots per subframe may vary between SCSs.

Note that the time direction (t) shown in FIG. 3 may be called the time domain, symbol period, symbol time, or the like. Also, the frequency direction may be called a frequency domain, resource block, subcarrier, bandwidth part (BWP: Bandwidth Part), or the like.

DMRS is a type of reference signal and is prepared for various channels. Here, unless otherwise specified, it may mean a downlink data channel, specifically DMRS for PDSCH (Physical Downlink Shared Channel). However, an uplink data channel, specifically, a DMRS for PUSCH (Physical Uplink Shared Channel) may be interpreted in the same way as a DMRS for PDSCH.

DMRS can be used for channel estimation in devices, eg, UE 200, as part of coherent demodulation. DMRS may reside only in resource blocks (RBs) used for PDSCH transmission.

A DMRS may have multiple mapping types. Specifically, DMRS has mapping type A and mapping type B. For mapping type A, the first DMRS is placed in the 2nd or 3rd symbol of the slot. In mapping type A, the DMRS may be mapped relative to slot boundaries, regardless of where in the slot the actual data transmission begins. The reason the first DMRS is placed in the second or third symbol of the slot may be interpreted as to place the first DMRS after the control resource sets (CORESET).

In mapping type B, the first DMRS may be placed in the first symbol of data allocation. That is, the position of the DMRS may be given relative to where the data is located rather than relative to slot boundaries.

In addition, DMRS may have multiple types (Type). Specifically, DMRS has Type 1 and Type 2. Type 1 and Type 2 differ in mapping in the frequency domain and the maximum number of orthogonal reference signals. Type 1 can output up to 4 orthogonal signals with single-symbol DMRS, and Type 2 can output up to 8 orthogonal signals with double-symbol DMRS.

(2) Functional Block Configuration of Radio Communication System Next, the functional block configuration of the radio communication system 10 will be described.

First, the functional block configuration of the UE200 will be explained.

FIG. 4 is a functional block diagram of the UE200. As shown in FIG. 4, the UE 200 includes a radio signal transmission/reception unit 210, an amplifier unit 220, a modem unit 230, a control signal/reference signal processing unit 240, an encoding/decoding unit 250, a data transmission/reception unit 260, and a control unit 270. .

The radio signal transmitting/receiving unit 210 transmits/receives radio signals according to NR. The radio signal transmitting/receiving unit 210 supports Massive MIMO, CA that bundles multiple CCs, and DC that simultaneously communicates between the UE and each of the two NG-RAN Nodes.

The amplifier section 220 is configured by a PA (Power Amplifier)/LNA (Low Noise Amplifier) and the like. Amplifier section 220 amplifies the signal output from modem section 230 to a predetermined power level. In addition, amplifier section 220 amplifies the RF signal output from radio signal transmission/reception section 210 .

The modulation/demodulation unit 230 executes data modulation/demodulation, transmission power setting, resource block allocation, etc. for each predetermined communication destination (gNB 100 or other gNB). The modem unit 230 may apply Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM)/Discrete Fourier Transform-Spread (DFT-S-OFDM). Also, DFT-S-OFDM may be used not only for uplink (UL) but also for downlink (DL).

The control signal/reference signal processing unit 240 executes processing related to various control signals transmitted and received by the UE 200 and processing related to various reference signals transmitted and received by the UE 200.

Specifically, the control signal/reference signal processing unit 240 receives various control signals transmitted from the gNB 100 via a predetermined control channel, for example, radio resource control layer (RRC) control signals. Also, the control signal/reference signal processing unit 240 transmits various control signals to the gNB 100 via a predetermined control channel.

The control signal/reference signal processing unit 240 executes processing using reference signals (RS) such as Demodulation Reference Signal (DMRS) and Phase Tracking Reference Signal (PTRS).

A DMRS is a known reference signal (pilot signal) between a terminal-specific base station and a terminal for estimating the fading channel used for data demodulation. PTRS is a terminal-specific reference signal for estimating phase noise, which is a problem in high frequency bands.

In addition to DMRS and PTRS, reference signals may include Channel State Information-Reference Signal (CSI-RS), Sounding Reference Signal (SRS), and Positioning Reference Signal (PRS) for position information.

Also, the channel includes a control channel and a data channel. Control channels include Physical Downlink Control Channel (PDCCH), Physical Uplink Control Channel (PUCCH), Random Access Channel (RACH), Downlink Control Information (DCI) including Random Access Radio Network Temporary Identifier (RA-RNTI), and Physical Broadcast Channel (PBCH) etc. are included.

In addition, data channels include PDSCH (Physical Downlink Shared Channel) and PUSCH (Physical Uplink Shared Channel). Data means data transmitted over a data channel. A data channel may be read as a shared channel.

Here, the control signal/reference signal processing unit 240 may receive downlink control information (DCI). DCI has existing fields such as DCI Formats, Carrier indicator (CI), BWP indicator, FDRA (Frequency Domain Resource Assignment), TDRA (Time Domain Resource Assignment), MCS (Modulation and Coding Scheme), HPN (HARQ Process Number) , NDI (New Data Indicator), RV (Redundancy Version), etc.

The value stored in the DCI Format field is an information element that specifies the DCI format. The value stored in the CI field is an information element that specifies the CC to which DCI is applied. The value stored in the BWP indicator field is an information element that specifies the BWP to which DCI applies. The BWP that can be specified by the BWP indicator is configured by an information element (BandwidthPart-Config) included in the RRC message. The value stored in the FDRA field is an information element that specifies the frequency domain resource to which DCI is applied. A frequency domain resource is identified by a value stored in the FDRA field and an information element (RA Type) included in the RRC message. The value stored in the TDRA field is an information element that specifies the time domain resource to which DCI applies. The time domain resource is specified by the value stored in the TDRA field and information elements (pdsch-TimeDomainAllocationList, pusch-TimeDomainAllocationList) included in the RRC message. A time-domain resource may be identified by a value stored in the TDRA field and a default table. The value stored in the MCS field is an information element that specifies the MCS to which DCI applies. The MCS is specified by the values stored in the MCS and the MCS table. The MCS table may be specified by RRC messages or identified by RNTI scrambling. The value stored in the HPN field is an information element that specifies the HARQ Process to which DCI is applied. The value stored in NDI is an information element for specifying whether data to which DCI is applied is initial transmission data. The value stored in the RV field is an information element that specifies the data redundancy to which DCI is applied.

The encoding/decoding unit 250 performs data segmentation/concatenation, channel coding/decoding, etc. for each predetermined communication destination (gNB 100 or other gNB).

Specifically, the encoding/decoding unit 250 divides the data output from the data transmission/reception unit 260 into pieces of a predetermined size, and performs channel coding on the divided data. Also, encoding/decoding section 250 decodes the data output from modem section 230 and concatenates the decoded data.

The data transmission/reception unit 260 executes transmission/reception of Protocol Data Unit (PDU) and Service Data Unit (SDU). Specifically, the data transmitting/receiving unit 260 performs PDU/SDU in multiple layers (medium access control layer (MAC), radio link control layer (RLC), packet data convergence protocol layer (PDCP), etc.). Assemble/disassemble etc. The data transmission/reception unit 260 also performs data error correction and retransmission control based on HARQ (Hybrid Automatic Repeat Request).

The control unit 270 controls each functional block that configures the UE200. In the embodiment, the control unit 270 controls the control signal/reference signal processing unit 240 described above. The control signal/reference signal processing unit 240 constitutes a transmitting unit that transmits feedback (hereinafter, delta-MCS) used in selecting a modulation scheme (hereinafter, MCS) used in a downlink channel (hereinafter, PDSCH). Control unit 270 is a control unit that executes specific control on transmission of delta-MCS based on the priority of delta-MCS when delta-MCS and channel state information (hereinafter referred to as CSI) overlap in time. configure.

The specific condition may be a condition that the index of the modulation scheme used in PDSCH (hereinafter referred to as MCS Index (I _MCS )) referred to in determining delta-MCS is a reserved MCS Index. Details of the specific condition and specific control will be described later.

The contents of delta-MCS are an information element that explicitly indicates the desired MCS, an information element that explicitly indicates the difference between the current MCS and the desired MCS, and an information element that explicitly indicates the difference between the current MCS and the desired MCS. at least one of the information elements indicating the index associated with the

Second, the functional block configuration of gNB100 will be explained.

FIG. 5 is a functional block configuration diagram of gNB100. As shown in FIG. 5, the gNB 100 has a receiver 110, a transmitter 120 and a controller .

The receiving unit 110 receives various signals from the UE200. The receiver 110 may receive the UL signal via PUCCH or PUSCH. Receiving section 110 may receive the delta-MCS used in selecting the MCS used in PDSCH.

The transmission unit 120 transmits various signals to the UE200. Transmitting section 120 may transmit the DL signal via PDCCH or PDSCH.

The control unit 130 controls the gNB100. Control section 130 may select an MCS to apply to PDSCH based on delta-MCS. Control section 130 may assume that, when delta-MCS and CSI temporally overlap, UE 200 performs specific control regarding transmission of delta-MCS based on the priority of delta-MCS.

(3) Priority The priority will be explained below. In an embodiment, we assume a case where delta-MCS is reported as a CSI report.

CSI types may include A (Aperiodic)-CSI, semi-persistent CSI, and periodic CSI. The channel used for CSI reporting may be PUCCH or PUSCH.

In such cases, the parameter that defines the priority of CSI (hereafter, Pri _iCSI (y, k, c, s)) may be expressed by the following formula (see TS38.214 Clause 5.2.5 ). Pri _iCSI (y,k,c,s) may be referred to as a priority value.

Pri _iCSI (y,k,c,s)=2・N _cells・M _s・y+ N _cells・M _s・k+ M _s・c+s
where y is a parameter defined by the CSI type and channel type. For example, y = 0 is used for A-CSI transmitted on PUSCH, y = 1 is used for semi-persistent CSI transmitted on PUSCH, and y = 2 is used for semi-persistent CSI transmitted on PUCCH. and y=3 is used for periodic CSI transmitted on PUCCH. k is a parameter defined by the content contained in the CSI report. You can think of k as a parameter that defines the priority of the report quantity. For example, k=0 may be used for CSI reports carrying L1-RSRP or L1-SINR and k=1 may be used for CSI reports not carrying L1-RSRP or L1-SINR. c is the index of the serving cell, and N _cells is the value of the higher layer parameter (maxNrofServingCells). S is the reportConfigID and M _s is the value of the upper layer parameter (maxNrofCSI-ReportConfigurations).

Furthermore, when there are two CSIs, the CSI with the lower value of Pri _iCSI (y, k, c, s) may be referred to as the first CSI, and Pri _iCSI (y, k, c, s) The CSI with the higher value of may be referred to as the second CSI.

For Pri _iCSI (y, k, c, s), the lower the value of Pri _iCSI (y, k, c, s), the more CSI associated with Pri _iCSI (y, k, c, s) is transmitted. You may think of it as a parameter defined to take precedence. In other words, the lower the value of Pri _iCSI (y, k, c, s), the higher the priority.

For example, two CSIs may be said to collide if the time occupancy of physical channels transmitted on the same carrier and scheduled to transmit CSI reports overlap by at least one OFDM symbol.

High as Pri _iCSI (y,k,c,s) except for the case where one y-value is 2 and the other y-value is 3 when the y-values of the two CSI reports are different A CSI report with a value may not be sent from the UE 200. In other cases, two CSI reports may be multiplexed and any one may be dropped based on Pri _iCSI (y,k,c,s). Such operations may be those described in 3GPP TS38.213 Clause 9.2.5.2.

Under this premise, consider the case where delta-MCS and CSI temporally overlap, as shown in FIG. In other words, consider the case where the time occupancy of physical channels scheduled to transmit CSI and delta-MCS reports overlap by at least one OFDM symbol. That is, consider a case where delta-MCS and CSI collide.

In such cases, the delta-MCS is reported as a CSI report, so it becomes necessary to set Pri _iCSI (y,k,c,s) for the delta-MCS. In the following we focus on the value of k that defines Pri _iCSI (y,k,c,s). The following options are possible for the value of k for delta-MCS.

In Option 1, the value of k for delta-MCS may be 0. That is, the value of k for delta-MCS may be the same as the value of k for L1-RSRP or L1-SINR. In such cases, it may be considered that k=0 is used for CSI reports carrying L1-RSRP, L1-SINR or delta-MCS.

In Option 2, the value of k for delta-MCS may be 1. That is, the value of k for delta-MCS may be the same as the value of k for CSI other than L1-RSRP or L1-SINR. CSI other than L1-RSRP or L1-SINR is CQI (Channel Quality Information), PMI (Precoding Matrix Indicator), CRI (CSI-RS Resource Indicator), SSBRI (SS/PBCH Resource Block Indicator), LI (Layer Indicator) , RI (Rank Indicator), etc.

In Option 3, the value of k for delta-MCS may be 2. That is, the value of k for delta-MCS may be a larger value than the existing CSI. In such cases, except for delta-MCS, consider k=1 to be used for CSI reports that do not carry L1-RSRP or L1-SINR, and k=2 to be used for CSI reports that carry delta-MCS. may 2, which can be taken as k, may be a newly defined value. Lower values of Pri _iCSI (y,k,c,s) are defined as higher priority, so in Option 3, we consider the delta-MCS priority to be lower than the existing CSI priority. good too. Existing CSI may include L1-RSRP, L1-SINR, CQ, PMI, CRI, SSBRI, LI, RI, and so on.

In Option 4, the value of k for delta-MCS can be -1. That is, the value of k for delta-MCS may be smaller than the existing CSI. In such cases, if k=−1 is used for CSI reports carrying delta-MCS and k=1 is used for CSI reports carrying L1-RSRP or L1-SINR, except for delta-MCS. You can think of it. -1, which can be taken as k, may be a newly defined value. Lower values of Pri _iCSI (y,k,c,s) are defined as higher priority, so in Option 4, we consider the delta-MCS priority to be higher than the existing CSI priority. good too. Existing CSI may include L1-RSRP, L1-SINR, CQ, PMI, CRI, SSBRI, LI, RI, and so on.

As described above, when delta-MCS and CSI (hereinafter, existing CSI) overlap in time, UE 200 executes specific control regarding transmission of delta-MCS based on the priority of delta-MCS. do. Specifically, based on delta-MCS Pri _iCSI (y, k, c, s) and existing CSI Pri _iCSI (y, k, c, s), UE 200 determines delta-MCS and existing CSI or drop any one of delta-MCS and existing CSI. Multiplexing of delta-MCS and existing CSI, and dropping any one of delta-MCS and existing CSI may be considered as examples of specific control regarding transmission of delta-MCS.

(4) Contents of feedback Although not particularly limited, the contents of feedback (delta-MCS) may be the contents shown below.

(4.1) First Example In the first example, the feedback content may include an information element (MCS Index) indicating a desired MCS. As the MCS Index, an MCS Index defined in the MCS Index table defined in 3GPP TS38.214 may be used.

Specifically, when the PDSCH transmitted with the MCS Index fails to be decoded, the UE 200 may include in the feedback an MCS Index lower than the MCS Index used for the PDSCH for which decoding failed as the desired MCS Index. For example, UE 200 may transmit feedback including MCS Index #0 to NG-RAN 20 (gNB 100) when decoding of PDSCH transmitted with MCS Index #5 fails.

With such a configuration, a large bit size is required for the feedback (UCI), but the content of the feedback (delta-MCS selection) is highly flexible. That is, the signaling load is relatively high, but the MCS flexibility that can be requested is high.

(4.2) Second example In a second example, the feedback content may include an information element indicating the difference between the current MCS and the desired MCS. The difference between the current MCS and the desired MCS may be the MCS Index difference defined in the MCS Index table defined in 3GPP TS38.214.

Specifically, when the PDSCH transmitted with the MCS Index fails to be decoded, the UE 200 may include in the feedback the difference between the MCS Index used for the PDSCH whose decoding failed and the desired MCS Index. The desired MCS Index may be lower than the current MCS Index. For example, when UE 200 fails to decode PDSCH transmitted with MCS Index #5 and requests MCS Index #2 as the desired MCS Index, feedback including "-3" is sent to NG-RAN 20 (gNB 100). You may send.

According to such a configuration, the flexibility of the feedback content (delta-MCS selection) is equivalent to that of the first example, and the feedback (UCI) bit size is small. That is, the signaling load can be suppressed as compared with the first example.

(4.3) Third Example In a third example, a table defined for feedback may be introduced. The following options are possible for the tables defined for feedback.

First, the content of feedback is an information element indicating the desired MCS, and the desired MCS may be selected from a table defined for feedback. As shown in FIG. 6, the table defined for feedback may be a table that associates MCS Index and Index that can be requested in feedback.

According to such a configuration, compared to the first example, the feedback content (delta-MCS selection) is less flexible, but the feedback (UCI) bit size is smaller. That is, the signaling load can be suppressed as compared with the first example.

Second, the content of the feedback is an index associated with the difference between the current MCS and the desired MCS (hereinafter referred to as delta value), and the index associated with the delta value is defined for feedback. may be selected from among the tables

According to such a configuration, compared to the second example, the feedback content (delta-MCS selection) is less flexible, but the feedback (UCI) bit size is smaller. That is, the signaling load can be suppressed as compared with the second example.

(5) Actions and Effects In the embodiment, when delta-MCS and existing CSI overlap in time, UE 200 executes specific control regarding transmission of delta-MCS based on the priority of delta-MCS. do. Specifically, under the premise that delta-MCS is reported as a CSI report, by clarifying the value of k that defines Pri _iCSI (y, k, c, s) of delta-MCS, delta-MCS can be sent properly.

(6) Other Embodiments Although the contents of the present invention have been described in accordance with the embodiments, it should be understood that the present invention is not limited to these descriptions and that various modifications and improvements are possible. self-evident to the trader.

In the above disclosure, delta-MCS is newly introduced, so it is distinguished from existing CSI, but delta-MCS may be considered one type of CSI.

Although not specifically mentioned in the above disclosure, which of the above options 1 to 4 is applied may be set by higher layer parameters, and may be reported by UE 200 capability information (UE Capability), It may be predetermined in the wireless communication system 10. Furthermore, which of the options 1 to 4 mentioned above is applied may be determined by higher layer parameters and UE Capabilities. In such cases, the UE Capability may contain an information element indicating which of options 1-4 is supported.

Although not specifically mentioned in the disclosure above, the UE Capability may include an information element indicating whether or not the function of reporting delta-MCS as CSI reporting is supported.

In the above disclosure, the specific condition is that the reserved MCS Index is specified by the DCI that schedules the PDSCH. However, the above disclosure is not so limited. A specific condition may be that the MCI Index required by delta-DCI can be a reserved MCS Index. In such cases, specific control may be to determine the value of delta-DCI such that no reserved MCS Index is required. For example, when the MCI Index specified by DCI in Tables 1 and 3 is 28, if delta-DCI is determined to be "-1" based on PDSCH, UE 200 uses " A specific control may be performed to send "0" as a specific delta-DCI without sending "-1". Similarly, when the MCI Index specified by DCI in Table 2 is 29, if delta-DCI is determined to be "-1" based on PDSCH, UE 200 sets "- A specific control may be performed to send "0" as a specific delta-DCI without sending "1".

In the above disclosure, the feedback content includes an information element (Delta-MCS) that explicitly indicates the desired MCS. However, the above disclosure is not so limited. The content of the feedback may include information elements that implicitly indicate the desired MCS. Such an information element may be a CQI (Channel Quality Indicator) that can be associated with MCS. A CQI that can be specified in the CQI table defined in 3GPP TS38.214 may be used as the CQI. That is, the feedback content may include an information element (Delta-CQI) that explicitly indicates the desired CQI. In such a case, MCS may be read as CQI, and MCS Index may be read as CQI Index.

In the above disclosure, the feedback content includes an information element (Delta-MCS) that explicitly indicates the difference between the current MCS and the desired MCS. However, the above disclosure is not so limited. The feedback content may include information elements that implicitly indicate the difference between the current MCS and the desired MCS. Such an information element may be a CQI that may be associated with MCS. A CQI that can be specified in the CQI table defined in 3GPP TS38.214 may be used as the CQI. That is, the feedback content may include an information element (Delta-CQI) that explicitly indicates the difference between the current CQI and the desired CQI. In such a case, MCS may be read as CQI, and MCS Index may be read as CQI Index.

In the above disclosure, the feedback content includes an information element (Delta-MCS) explicitly associated with the difference between the current MCS and the desired MCS. However, the above disclosure is not so limited. The feedback content may include information elements implicitly associated with the difference between the current MCS and the desired MCS. Such an information element may be a CQI that may be associated with MCS. A CQI that can be specified in the CQI table defined in 3GPP TS38.214 may be used as the CQI. That is, the feedback content may include an information element (Delta-CQI) explicitly associated with the difference between the current CQI and the desired CQI. In such a case, MCS may be read as CQI, and MCS Index may be read as CQI Index.

In the above disclosure, the table defined for feedback is the table for MCS. However, the above disclosure is not so limited. The table defined for feedback may be a table for CQI. For example, the feedback content may include an Index associated with the desired CQI Index, or may include an Index associated with the difference between the current CQI and the desired CQI. In such a case, MCS may be read as CQI, and MCS Index may be read as CQI Index.

Although not particularly mentioned in the above disclosure, as the content of the feedback, whether to use feedback on MCS (Delta-MCS) or feedback on CQI (Delta-CQI) may be set by a higher layer parameter, It may be reported by UE 200 capability information (UE Capability), or may be predetermined in the wireless communication system 10 . Furthermore, which of the above options to apply may be determined by higher layer parameters and UE Capabilities.

The block configuration diagrams (FIGS. 4 and 5) used to describe the above-described embodiment show blocks in functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Also, the method of implementing each functional block is not particularly limited. That is, each functional block may be implemented using one device that is physically or logically coupled, or directly or indirectly using two or more devices that are physically or logically separated (e.g. , wired, wireless, etc.) and may be implemented using these multiple devices. A functional block may be implemented by combining software in the one device or the plurality of devices.

Functions include judging, determining, determining, calculating, calculating, processing, deriving, investigating, searching, checking, receiving, transmitting, outputting, accessing, resolving, selecting, choosing, establishing, comparing, assuming, expecting, assuming, Broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc. can't For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. In either case, as described above, the implementation method is not particularly limited.

Furthermore, the gNB 100 and UE 200 (applicable device) described above may function as a computer that performs processing of the wireless communication method of the present disclosure. FIG. 7 is a diagram showing an example of the hardware configuration of the device. As shown in FIG. 7, the device may be 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, and the like.

In the following explanation, the term "apparatus" can be read as a circuit, device, unit, or the like. The hardware configuration of the device may be configured to include one or more of each device shown in the figure, or may be configured without some of the devices.

Each functional block of the device (see FIG. 4) is realized by any hardware element of the computer device or a combination of the hardware elements.

In addition, each function of the device is implemented by causing the processor 1001 to perform calculations, controlling communication by the communication device 1004, and controlling the It is realized by controlling at least one of data reading and writing in 1002 and storage 1003 .

A processor 1001, for example, operates an operating system and controls the entire computer. The processor 1001 may be configured by a central processing unit (CPU) including interfaces with peripheral devices, a control unit, an arithmetic unit, registers, and the like.

Also, the processor 1001 reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 to the memory 1002, and executes various processes according to them. As the program, a program that causes a computer to execute at least part of the operations described in the above embodiments is used. Furthermore, the above-described various processes may be executed by one processor 1001, or may be executed by two or more processors 1001 simultaneously or sequentially. Processor 1001 may be implemented by one or more chips. Note that the program may be transmitted from a network via an electric communication line.

The memory 1002 is a computer-readable recording medium, and is composed of at least one of Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), Random Access Memory (RAM), etc. may be The memory 1002 may also be called a register, cache, main memory (main storage device), or the like. The memory 1002 can store programs (program code), software modules, etc. capable of executing a method according to an embodiment of the present disclosure.

The storage 1003 is a computer-readable recording medium, for example, an optical disc such as a Compact Disc ROM (CD-ROM), a hard disk drive, a flexible disc, a magneto-optical disc (for example, a compact disc, a digital versatile disc, a Blu-ray disk), smart card, flash memory (eg, card, stick, key drive), floppy disk, magnetic strip, and/or the like. Storage 1003 may also be referred to as an auxiliary storage device. The recording medium described above may be, for example, a database, server, or other suitable medium including at least one of memory 1002 and storage 1003 .

The communication device 1004 is hardware (transmitting/receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also called a network device, a network controller, a network card, a communication module, or the like.

The communication device 1004 includes a high-frequency switch, duplexer, filter, frequency synthesizer, etc., for realizing at least one of frequency division duplex (FDD) and time division duplex (TDD). may consist of

The input device 1005 is an input device (for example, keyboard, mouse, microphone, switch, button, sensor, etc.) that receives input from the outside. The output device 1006 is an output device (eg, display, speaker, LED lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated (for example, a touch panel).

Also, 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 devices.

In addition, the device includes hardware such as a microprocessor, digital signal processor (DSP), application specific integrated circuit (ASIC), programmable logic device (PLD), field programmable gate array (FPGA), etc. A part or all of each functional block may be implemented by the hardware. For example, processor 1001 may be implemented using at least one of these pieces of hardware.

In addition, 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 may include physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI), higher layer signaling (e.g., RRC signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB), other signals, or a combination thereof, and RRC signaling may also be referred to as RRC messages, e.g., RRC Connection Setup ) message, RRC Connection Reconfiguration message, or the like.

Each aspect/embodiment described in this disclosure includes Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system ( 5G), Future Radio Access (FRA), New Radio (NR), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)) , IEEE 802.16 (WiMAX®), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth®, other suitable systems, and/or next-generation systems enhanced therefrom. may be applied to Also, a plurality of systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A and 5G).

The order of the processing procedures, sequences, flowcharts, etc. of each aspect/embodiment described in the present disclosure may be changed as long as there is no contradiction. For example, the methods described in this disclosure present elements of the various steps using a sample order, and are not limited to the specific order presented.

A specific operation that is performed by a base station in the present disclosure may be performed by its upper node in some cases. In a network consisting of one or more network nodes with a base station, various operations performed for communication with a terminal may be performed by the base station and other network nodes other than the base station (e.g. MME or S-GW, etc., but not limited to). Although the case where there is one network node other than the base station is exemplified above, it may be a combination of a plurality of other network nodes (for example, MME and S-GW).

Information, signals (information, etc.) can be output from a higher layer (or a lower layer) to a lower layer (or a higher layer). It may be input and output via multiple network nodes.

Input/output information may be stored in a specific location (for example, memory) or managed using a management table. Input and output information may be overwritten, updated, or appended. The output information may be deleted. The entered information may be transmitted to other devices.

The determination may be made by a value represented by one bit (0 or 1), by a true/false value (Boolean: true or false), or by numerical comparison (for example, a predetermined value).

Each aspect/embodiment described in the present disclosure may be used alone, may be used in combination, or may be used by switching along with execution. In addition, the notification of predetermined information (for example, notification of “being X”) is not limited to being performed explicitly, but may be performed implicitly (for example, not notifying the predetermined information). good too.

Software, whether referred to as software, firmware, middleware, microcode, hardware description language or otherwise, includes instructions, instruction sets, code, code segments, program code, programs, subprograms, and software modules. , applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and the like.

In addition, software, instructions, information, etc. may be transmitted and received via a transmission medium. For example, the Software uses wired technology (coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), etc.) and/or wireless technology (infrared, microwave, etc.) to access websites, Wired and/or wireless technologies are included within the definition of transmission medium when sent from a server or other remote source.

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 refer to voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these. may be represented by a combination of

The terms explained in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, the channel and/or symbols may be signaling. A signal may also be a message. A component carrier (CC) may also be called a carrier frequency, a cell, a frequency carrier, or the like.

The terms "system" and "network" used in this disclosure are used interchangeably.

In addition, 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. may be represented. For example, radio resources may be indexed.

The names used for the parameters described above are not restrictive names in any respect. Further, the formulas, etc., using these parameters may differ from those expressly disclosed in this disclosure. Since the various channels (e.g., PUCCH, PDCCH, etc.) and information elements can be identified by any suitable designation, the various designations assigned to these various channels and information elements are in no way restrictive designations. isn't it.

In the present disclosure, "base station (BS)", "radio base station", "fixed station", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", " "access point", "transmission point", "reception point", "transmission/reception point", "cell", "sector", "cell group", " Terms such as "carrier", "component carrier" may be used interchangeably. A base station may also be referred to by terms such as macrocell, small cell, femtocell, picocell, and the like.

A base station can accommodate one or more (eg, three) cells (also called sectors). When a base station accommodates multiple cells, the overall coverage area of the base station can be partitioned into multiple smaller areas, each smaller area corresponding to a base station subsystem (e.g., a small indoor base station (Remote Radio)). Head: RRH) can also provide communication services.

The term "cell" or "sector" refers to part or all of the coverage area of at least one of a base station and base station subsystem that provides communication services in this coverage.

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

A mobile station is defined by those skilled in the art 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 It may also be called a terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable term.

At least one of the base station and mobile station may be called a transmitting device, a receiving device, a communication device, or the like. At least one of the base station and the mobile station may be a device mounted on a mobile object, the mobile object itself, or the like. The mobile object may be a vehicle (e.g., car, airplane, etc.), an unmanned mobile object (e.g., drone, self-driving car, etc.), or a robot (manned or unmanned ). Note that at least one of the base station and the mobile station includes devices that do not necessarily move during communication operations. For example, at least one of the base station and mobile station may be an Internet of Things (IoT) device such as a sensor.

Also, the base station in the present disclosure may be read as a mobile station (user terminal, hereinafter the same). For example, communication between a base station and a mobile station is replaced with communication between multiple mobile stations (for example, Device-to-Device (D2D), Vehicle-to-Everything (V2X), etc.) Regarding the configuration, each aspect/embodiment of the present disclosure may be applied. In this case, the mobile station may have the functions that the base station has. Also, words such as "up" and "down" may be replaced with words corresponding to inter-terminal communication (for example, "side"). For example, uplink channels, downlink channels, etc. may be read as side channels.

Similarly, a mobile station in the present disclosure may be read as a base station. In this case, the base station may have the functions that the mobile station has.

A radio frame may consist of one or more frames in the time domain. Each frame or frames in the time domain may be referred to as a subframe.

A subframe may further consist of one or more slots in the time domain. A subframe may be a fixed time length (eg, 1 ms) independent of numerology.

A numerology may be a communication parameter that applies to the transmission and/or reception of a signal or channel. Numerology, for example, subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, transmission and reception specific filtering operations performed by the receiver in the frequency domain, specific windowing operations performed by the transceiver in the time domain, and/or the like.

A slot may consist of one or more symbols (Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.) in the time domain. A slot may be a unit of time based on numerology.

A slot may contain multiple mini-slots. Each minislot may consist of one or more symbols in the time domain. A minislot may also be referred to as a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) that is transmitted in time units larger than a minislot may be referred to as PDSCH (or PUSCH) mapping type A. PDSCH (or PUSCH) transmitted using minislots may be referred to as PDSCH (or PUSCH) mapping type B.

Radio frames, subframes, slots, minislots and symbols all represent time units when transmitting signals. Radio frames, subframes, slots, minislots and symbols may be referred to by other corresponding designations.

For example, one subframe may be called a transmission time interval (TTI), a plurality of consecutive subframes may be called a TTI, and one slot or one minislot may be called a TTI. That is, at least one of the subframe and TTI may be a subframe (1ms) in existing LTE, may be a period shorter than 1ms (eg, 1-13 symbols), or a period longer than 1ms may be Note that the unit representing the TTI may be called a slot, minislot, or the like instead of a subframe.

Here, TTI refers to, for example, the minimum scheduling time unit in wireless communication. For example, in the LTE system, a base station performs scheduling to allocate radio resources (frequency bandwidth, transmission power, etc. that can be used by each user terminal) to each user terminal on a TTI basis. Note that the definition of TTI is not limited to this.

The TTI may be a transmission time unit for channel-encoded data packets (transport blocks), code blocks, codewords, etc., or may be a processing unit for scheduling, link adaptation, etc. Note that when a TTI is given, the time interval (for example, the number of symbols) in which transport blocks, code blocks, codewords, etc. are actually mapped may be shorter than the TTI.

If one slot or one minislot is called a TTI, one or more TTIs (that is, one or more slots or one or more minislots) may be the minimum scheduling time unit. Also, the number of slots (the number of mini-slots) constituting the minimum time unit of the scheduling may be controlled.

A TTI with a time length of 1 ms may be called a normal TTI (TTI in LTE Rel.8-12), normal TTI, long TTI, normal subframe, normal subframe, long subframe, slot, etc. A TTI that is shorter than a normal TTI may also be called a shortened TTI, a short TTI, a partial or fractional TTI, a shortened subframe, a short subframe, a minislot, a subslot, a slot, and so on.

In addition, long TTI (for example, normal TTI, subframe, etc.) may be read as TTI having a time length exceeding 1 ms, and short TTI (for example, shortened TTI, etc.) is less than the TTI length of long TTI and 1 ms. A TTI having a TTI length greater than or equal to this value may be read as a replacement.

A resource block (RB) is a resource allocation unit in the time domain and 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 neurology, and may be 12, for example. The number of subcarriers included in an RB may be determined based on neumerology.

Also, the time domain of an RB may include one or more symbols and may be 1 slot, 1 minislot, 1 subframe, or 1 TTI long. One TTI, one subframe, etc. may each be configured with one or a plurality of resource blocks.

One or more RBs are physical resource blocks (PRB), sub-carrier groups (SCG), resource element groups (REG), PRB pairs, RB pairs, etc. may be called.

Also, a resource block may be composed of one or more resource elements (Resource Element: RE). For example, 1 RE may be a radio resource region of 1 subcarrier and 1 symbol.

A Bandwidth Part (BWP) (which may also be called a Bandwidth Part) represents a subset of contiguous common resource blocks (RBs) for a neumerology in a carrier. good. Here, the common RB may be identified by an RB index based on the common reference point of the carrier. PRBs may be defined in a BWP and numbered within that BWP.

BWP may include BWP for UL (UL BWP) and BWP for DL (DL BWP). One or more BWPs may be configured in one carrier for the UE.

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 "cell", "carrier", etc. in the present disclosure may be read as "BWP".

The structures such as radio frames, subframes, slots, minislots and symbols described above are only 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 Configurations such as the number of subcarriers and the number of symbols in a TTI, symbol length, cyclic prefix (CP) length, etc. can be varied.

The terms "connected," "coupled," or any variation thereof, mean any direct or indirect connection or coupling between two or more elements, It can include the presence of one or more intermediate elements between two elements being "connected" or "coupled." Couplings or connections between elements may be physical, logical, or a combination thereof. For example, "connection" may be read as "access". As used in this disclosure, two elements are defined using at least one of one or more wires, cables, and printed electrical connections and, as some non-limiting and non-exhaustive examples, in the radio frequency domain. , electromagnetic energy having wavelengths in the microwave and optical (both visible and invisible) regions, and the like.

The reference signal can also be abbreviated as Reference Signal (RS), and may also be called Pilot depending on the applicable standard.

The term "based on" as used in this disclosure does not mean "based only on" unless otherwise specified. In other words, the phrase "based on" means both "based only on" and "based at least on."

"Means" in the configuration of each device described above may be replaced with "unit", "circuit", "device", or the like.

Any reference to elements using the "first", "second", etc. designations used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, references to first and second elements do not imply that only two elements may be employed therein, or that the first element must precede the second element in any way.

Where "include," "including," and variations thereof are used in this disclosure, these terms are inclusive, as is the term "comprising." is intended. Furthermore, the term "or" as used in this disclosure is not intended to be an exclusive OR.

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

The terms "determining" and "determining" used in this disclosure may encompass a wide variety of actions. "Judgement" and "determination" are, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (eg, lookup in a table, database, or other data structure), ascertaining as "judged" or "determined", and the like. Also, "judgment" and "determination" are used for receiving (e.g., receiving information), transmitting (e.g., transmitting information), input, output, access (accessing) (for example, accessing data in memory) may include deeming that a "judgment" or "decision" has been made. In addition, "judgment" and "decision" are considered to be "judgment" and "decision" by resolving, selecting, choosing, establishing, comparing, etc. can contain. In other words, "judgment" and "decision" may include considering that some action is "judgment" and "decision". Also, "judgment (decision)" may be read as "assuming", "expecting", "considering", or the like.

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 that "A and B are different from C". Terms such as "separate," "coupled," etc. may also be interpreted in the same manner as "different."

Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure can be practiced with modifications and variations without departing from the spirit and scope of the present disclosure as defined by the claims. Accordingly, the description of the present disclosure is for illustrative purposes and is not meant to be limiting in any way.

10 Radio communication system 20 NG-RAN
100 gNB
110 receiver 120 transmitter 130 controller 200 UE
210 radio signal transmission/reception unit 220 amplifier unit 230 modulation/demodulation unit 240 control signal/reference signal processing unit 250 encoding/decoding unit 260 data transmission/reception unit 270 control unit 1001 processor 1002 memory 1003 storage 1004 communication device 1005 input device 1006 output device 1007 bus

Claims (5)

1. a transmitter that transmits feedback used in selecting a modulation scheme used in a downlink channel;
   and a control unit that performs specific control on transmission of the feedback based on the priority of the feedback when the feedback and channel state information overlap in time.
2. The terminal according to claim 1, wherein the priority of the feedback is lower than the priority of the channel state information.
3. The terminal according to claim 1, wherein the priority of the feedback is higher than the priority of the channel state information.
4. comprising a terminal and a base station,
   The terminal is
   a transmitter that transmits feedback used in selecting a modulation scheme used in a downlink channel;
   a control unit that performs specific control on transmission of the feedback based on priority of the feedback when the feedback and channel state information overlap in time.
5. transmitting feedback for use in selecting a modulation scheme for use on a downlink channel;
   and performing a specific control on transmission of the feedback based on the priority of the feedback when the feedback and channel state information overlap in time.

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