Terminal, base station and communication method

Abstract

A terminal according to the present invention is provided with: a reception circuit that receives a report instruction for a time region in which phase continuity and power consistency of an uplink signal need to be maintained; and a control circuit configured to determine a periodic report of the time region according to the report instruction.

Description

Technical Field

[0001] The present disclosure relates to a terminal, a base station, and a communication method. Background Art

[0002] In terms of 5G standardization, the new radio access technology (NR) has been standardized by the 3GPP (3rd Generation Partnership Project), and the specifications of NR version (Release) 15 (Rel.15) have been released.

[0003] Prior art literature

[0004] Non-patent literature

[0005] Non-Patent Document 1: 3GPP, TR 38.821, V16.1.0 “Solutions for NR to support non-terrestrial networks (NTN) (Release 16)”

[0006] Non-Patent Document 2: 3GPP, TS 38.214, V17.3.0 “NR; Physical layer procedures for data (Release 17)” Summary of the Invention

[0007] However, there is still room for research on the reporting method of the time period in which the phase continuity and power consistency of the uplink signal are maintained.

[0008] The non-limiting embodiments of the present disclosure contribute to providing a terminal, a base station, and a communication method that can appropriately report a time period in which phase continuity and power consistency of an uplink signal are maintained.

[0009] A terminal of one embodiment of the present disclosure comprises: a receiving circuit for receiving a report indication of a time zone, which is a time zone in which the phase continuity and power consistency of the uplink signal need to be maintained; and a control circuit for determining the periodic reporting of the time zone according to the report indication.

[0010] In addition, these broad or specific embodiments may be implemented by systems, devices, methods, integrated circuits, computer programs, or recording media, or by any combination of systems, devices, methods, integrated circuits, computer programs, and recording media.

[0011] According to one embodiment of the present disclosure, it is possible to appropriately report a time zone in which phase continuity and power consistency of an uplink signal are maintained.

[0012] Further advantages and effects of an embodiment of the present disclosure will be clarified through the description and drawings. These advantages and / or effects are provided by several embodiments and the features described in the description and drawings, but not all of them need to be provided in order to obtain one or more of the same features. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a diagram illustrating TDW.

[0014] Figure 2 This is a block diagram showing a configuration example of a part of a terminal.

[0015] Figure 3 This is a block diagram showing a configuration example of a portion of a base station.

[0016] Figure 4 This is a block diagram showing an example of the configuration of a terminal according to the first embodiment.

[0017] Figure 5 This is a block diagram showing an example of the configuration of a base station according to Embodiment 1.

[0018] Figure 6 This is a flowchart showing an example of terminal operation in the first embodiment.

[0019] Figure 7 A diagram illustrating an operation example of a terminal and a base station.

[0020] Figure 8 is a diagram of an exemplary architecture of a 3GPP NR system.

[0021] Figure 9 This diagram shows the functional separation between NG-RAN (Next Generation-Radio Access Network) and 5GC (5th Generation Core).

[0022] Figure 10 This is a sequence diagram of the process of setting up / resetting an RRC (Radio Resource Control) connection.

[0023] Figure 11This is a schematic diagram showing the utilization scenarios of large-capacity high-speed communications (eMBB: enhanced Mobile Broadband), multi-simultaneous machine-type communications (mMTC: massive Machine Type Communications), and highly reliable and low-latency communications (URLLC: Ultra Reliable and Low Latency Communications).

[0024] Figure 12 is a block diagram representing an exemplary 5G system architecture for a non-roaming scenario.

[0025] Figure 13 This is a diagram illustrating an example of a possible TDW report.

[0026] Figure 14 This is a diagram illustrating an example of reporting auxiliary information. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0028] [About Non-Terrestrial Networks (NTN)]

[0029] NR Rel.15 has been standardized as a wireless access technology for terrestrial networks. Meanwhile, research is underway to expand NR to non-terrestrial networks (NTNs), such as communications using satellites or high-altitude pseudo-satellites (HAPS). (For example, see Non-Patent Document 1.)

[0030] In an NTN environment, satellite coverage (e.g., one or more cells) for ground-based terminals (e.g., also called "user equipment" (UE)) and overhead terminals such as aircraft and drones is formed by satellite beams (e.g., also called "satellite beams"). Furthermore, the round-trip time (RTT) for radio wave propagation between a terminal and the satellite depends on the satellite's altitude (e.g., a maximum of approximately 36,000 km) and the angle of view from the terminal—that is, the positional relationship between the satellite and the terminal.

[0031] For example, Non-Patent Document 1 describes that in NTN, the round-trip time (RTT) of radio wave propagation between a base station (eg, a base station mounted on a satellite) and a terminal takes a maximum of approximately 540 ms.

[0032] In addition, non-patent document 1 records that in NTN, depending on the position of the terminal within the beam (or, coverage area or cell), a maximum delay difference of about 10ms will occur (for example, the difference between the position farthest from the satellite and the position closest to the satellite within the beam).

[0033] Furthermore, in the case of non-geostationary satellites, such as low-Earth orbit satellites (LEO), propagation delay varies significantly compared to terrestrial networks because the satellites move at a high speed of approximately 7.6 km per second. Furthermore, in NTNs, the high-speed movement of satellites causes a higher Doppler shift (or frequency shift) compared to terrestrial networks.

[0034] (Timing control and frequency control)

[0035] In NR, for example, each terminal performs timing control based on timing correction information, such as a "Timing Advance (TA) command," notified by the base station, so that the base station receives the same signals transmitted from each terminal. In other words, each terminal controls the transmission timing of uplink signals.

[0036] As mentioned above, in NTNs, propagation delays vary significantly compared to terrestrial networks. Therefore, terminals calculate the round-trip delay between the terminal and the base station and correct the timing before transmitting signals. This timing correction is also called "timing pre-compensation."

[0037] For example, the latency of the wireless link between the terminal and the satellite (e.g., the "service link") is calculated based on the terminal's location information and information related to the satellite's orbit or position. It should be noted that the terminal's location information can be obtained, for example, from a Global Navigation Satellite System (GNSS) in the terminal. Furthermore, information related to the satellite's orbit or position can be reported (e.g., broadcast) to the terminal by the base station as "satellite ephemeris information" (also known as satellite ephemeris).

[0038] For example, the terminal calculates the delay time of a wireless link (e.g., called a "feeder link") between a ground base station or a gateway (GW) and a satellite based on a common TA parameter broadcasted from the base station.

[0039] The delay of the feeder link changes as the satellite moves. Therefore, in addition to the delay of the feeder link at a certain point in time, information related to the variation in the delay, such as common TA drift and common TA drift variation, is also notified to the terminal as common TA parameters.

[0040] For example, the terminal can determine the value T used for timing control (adjustment) based on equation (1): TA .

[0041] [Formula 1]

[0042] (1)

[0043] In formula (1), N TA For example, N indicates the TA value notified by the TA command. TAoffset Indicates the offset relative to the TA value, T c Indicates a base time (e.g., a basic time unit).

[0044] In addition, in formula (1), N TA,adj common represents the universal TA value of the feeder link delay calculated based on universal TA parameters, N TA,adj UE It represents the terminal-specific TA value based on the service link delay estimated by the terminal according to the terminal's location information and satellite positions.

[0045] In addition, the first and second terms of formula (1) are specified in 5G NR standard TS 38.211, for example, and are the same as Rel.15NR specifications. TA The value of the first and second items is the value of the general TA value (N TA,adj common ) and terminal-specific TA value (N TA,adj UE ) added together.

[0046] In this way, in NTN, the round-trip delay of the serving link and the feeder link is corrected (e.g., compensated) on the terminal side before transmitting the uplink signal. This allows the base station to receive signals transmitted from each terminal within a predetermined time difference.

[0047] In addition, in NTN, high Doppler frequency shift may occur due to the high-speed movement of satellites. The Doppler frequency shift varies according to the terminal position and changes at all times. Therefore, it may be difficult for the base station to receive signals from multiple terminals. Thus, the terminal transmits signals using a frequency obtained by pre-compensating the Doppler frequency shift of the service link. For example, the Doppler frequency shift is calculated based on the satellite position, satellite speed, and terminal position. Therefore, the terminal can calculate the Doppler frequency shift correction amount based on the satellite ephemeris information and the position information of the terminal. Such frequency correction is also called "frequency pre-compensation".

[0048] <DMRS bundling>

[0049] In NR Rel.17, for the repeatedly transmitted PUSCH or PUCCH in the uplink, DMRS (Demodulation Reference Signal) bundling is supported. In DMRS bundling, the terminal performs repeated transmission while maintaining phase continuity and power consistency across multiple time slots. In the base station, joint channel estimation (JCE: Joint Channel Estimation) is performed by combining the DMRS of these time slots to improve the channel estimation accuracy.

[0050] The period during which phase continuity and power consistency are maintained is called the TDW (Time Domain Window). For example, the time during which phase continuity and / or power consistency can be maintained in the terminal varies according to the performance of HW (Hardware) such as the power amplifier and oscillator of the terminal. Therefore, the terminal reports the value of the TDW to the base station as the UE (User Equipment) capability.

[0051] Based on the reported UE capability, the base station fixedly or semi-statically configures the TDW into the terminal. The configured TDW is called the "configured TDW" or "nominal TDW".

[0052] When the terminal repeatedly transmits the PUSCH, it needs to maintain phase continuity and power consistency during the configured TDW.

[0053] For example, as Figure 1As shown, when TDW=4 slots is set, when transmitting PUSCH with 8 repetitions, the terminal transmits while maintaining phase continuity and power consistency in the first 4 slots and the second 4 slots.

[0054] Furthermore, the TDW that actually maintains phase continuity and power consistency is referred to as "actual TDW." For example, if an event occurs that makes phase continuity and power consistency unmaintainable, such as a change in transmit power due to a transmit power control command, the nominal TDW can be divided into multiple actual TDWs. In addition to changes in transmit power, other events include changes in frequency resources due to frequency hopping and changes in transmit timing due to a TA command.

[0055] For example, Figure 1 As shown, when frequency hopping causes a frequency resource change after the first two slots, every two slots in the first four slots become one actual TDW. The terminal maintains phase continuity and power consistency within the actual TDW. Non-Patent Document 2 describes the details of DMRS bundling.

[0056] <Discussion>

[0057] Because NTN involves long-distance transmission, conventional smartphones and other devices may have difficulty communicating with satellites at high altitudes or low elevation angles due to low transmission output and antenna gain. Therefore, 3GPP is studying repeated transmission. Furthermore, to further expand coverage, the use of DMRS bundling is under investigation.

[0058] Furthermore, in NTN, as described above, in order to reduce the influence of high-speed moving satellites, terminals autonomously perform timing control and frequency control according to the positions of the satellites and the terminals.

[0059] Here, the amount of change in propagation delay or Doppler shift varies depending on the satellite's location and elevation angle. For example, the amount of change in propagation delay per unit time (timing drift rate) decreases as the satellite moves from a low elevation angle to a high elevation angle. On the other hand, the amount of change in Doppler shift per unit time increases as the satellite moves from a low elevation angle to a high elevation angle.

[0060] Therefore, the update cycle of timing and / or frequency control required to suppress the timing error within a predetermined range varies depending on the position of the satellite. In particular, it is required to track time fluctuations in a shorter time than frequency fluctuations.

[0061] Furthermore, even when the transmission timing of the uplink signal is kept constant (ie, not updated) in the terminal, phase rotation occurs when the uplink signal is received in the base station due to variations in propagation delay time.

[0062] Therefore, when the position or elevation angle of the satellite is certain, it may be impossible to maintain phase continuity within the TDW set in a fixed (or semi-static) manner by the base station.

[0063] Therefore, in the method described above, in which the TDW value based on the terminal's HW performance is reported to the base station as the terminal capability, and the base station fixedly or semi-statically configures the TDW for the terminal based on the terminal capability report, it is difficult to appropriately perform joint channel estimation in the base station.

[0064] The present disclosure provides a new mechanism for notifying and / or setting TDW.

[0065] <Communication System Overview>

[0066] A communication system according to an embodiment of the present disclosure includes a terminal 100 and a base station 200 .

[0067] Figure 2 1 is a block diagram showing a configuration example of a portion of the terminal 100. Figure 2 In the illustrated terminal 100, a receiving unit (e.g., corresponding to a receiving circuit) receives a TDW reporting instruction from a base station 200, indicating that the TDW is required to maintain phase continuity and power consistency of the uplink signal. A control unit (e.g., corresponding to a control circuit) determines the periodicity of TDW reporting based on the reporting instruction from the base station 200.

[0068] Figure 3 2 is a block diagram showing a configuration example of a part of the base station 200. Figure 3 In the illustrated base station 200, a transmitting unit (e.g., corresponding to a transmitting circuit) sends a TDW report instruction to terminal 100. This TDW is required to maintain phase continuity and power consistency of the uplink signal. A control unit (e.g., corresponding to a control circuit) performs joint channel estimation based on the TDW reports periodically received from terminal 100.

[0069] The above operations enable appropriate TDW reporting while maintaining phase continuity and power consistency of uplink signals. Appropriate joint channel estimation is enabled by appropriate TDW reporting.

[0070] Hereinafter, timing control and / or frequency control may be described as timing / frequency control.

[0071] <Implementation Method 1>

[0072] In Embodiment 1, the terminal reports the TDW value, which takes into account HW performance, to the base station as the terminal's capabilities. Furthermore, the terminal repeatedly reports to the base station the TDW (possible TDW) that can maintain the terminal's phase continuity and power consistency, taking into account, for example, the timing / frequency control update period (update frequency) that varies with satellite movement.

[0073] The base station determines the time slot used for joint channel estimation based on the TDW information included in the terminal capabilities notified from the terminal and the TDW information reported periodically. In addition, the base station notifies the terminal of the TDW in the PUSCH allocation notification.

[0074] <<Terminal Structure>>

[0075] Figure 4 This is a block diagram showing an example of the configuration of terminal 100 according to Embodiment 1. Terminal 100 includes a wireless reception unit 101 , a data reception processing unit 102 , a control unit 103 , a timing / frequency adjustment unit 104 , a data transmission processing unit 105 , and a wireless transmission unit 106 .

[0076] The wireless receiving unit 101 performs analog and digital reception processing such as down-conversion, A / D conversion, and filtering on the signal received from the base station 200 via the antenna, and outputs it to the data reception processing unit 102. The wireless receiving unit 101 outputs information on the reception timing of the SSB (Synchronization Signal (SS) / Physical Broadcast Channel (PBCH) Block) to the timing / frequency adjustment unit 104.

[0077] The data reception processing unit 102 demodulates and decodes downlink signals such as the SSB, PDCCH, and PDSCH output from the wireless reception unit 101. The PDCCH includes resource allocation information for the PDSCH, resource allocation information for the PUSCH, and resource allocation information for the PUCCH used to transmit HARQ-ACK for the PDSCH. Furthermore, the PDSCH includes, in addition to user data, broadcast information such as system information, RRC control information, MAC CE control information, RACH responses (e.g., Msg2), and TA commands.

[0078] PDCCH is the abbreviation for Physical Downlink Control Channel. PDSCH is the abbreviation for Physical Downlink Shared Channel. HARQ-ACK is the abbreviation for Hybrid Automatic Repeat Request-Acknowledgement. RRC is the abbreviation for Radio Resource Control. MAC CE is the abbreviation for Medium Access Control Control Element. RACH is the abbreviation for Random Access Channel.

[0079] The data reception processing unit 102 receives and processes information related to TDW (e.g., nominal TDW) configuration and information for enabling TDW notification, included in RRC control information (e.g., RRC Reconfiguration message), and outputs the information to the control unit 103. The data reception processing unit 102 outputs TDW (e.g., actual TDW) configuration information included in MAC CE, PDCCH, and Msg2 to the control unit 103. The data reception processing unit 102 also outputs information such as satellite ephemeris, universal TA parameters, and epoch time included in broadcast information to the control unit 103.

[0080] The control unit 103 obtains the location information of the terminal 100 from, for example, a GNSS. Furthermore, the control unit 103 calculates the satellite's orbit and position based on information such as the satellite ephemeris and epoch time output from the data reception processing unit 102. Using the round-trip delay between the terminal and the satellite calculated based on this location information and the round-trip delay between the satellite and the base station calculated based on the universal TA parameters, the control unit 103 calculates a timing adjustment value (TA value) and outputs it to the timing / frequency adjustment unit 104.

[0081] The control unit 103 calculates the Doppler shift based on the satellite orbit information and the terminal position information of the terminal 100 , and outputs the calculated Doppler shift to the timing / frequency adjustment unit 104 .

[0082] The control unit 103 sets the TDW of the PUSCH and the PUCCH based on the TDW information received from the base station 200 and output from the data reception processing unit 102 , and outputs the TDW to the timing / frequency adjustment unit 104 .

[0083] The control unit 103 outputs the TDW capability that can maintain phase continuity and power consistency to the data transmission processing unit 105. The TDW capability is a capability that takes into account the performance of hardware such as the wireless transmission unit 106 of the terminal 100. For example, the TDW capability is transmitted as a terminal capability via an RRC message.

[0084] The control unit 103 calculates the TDW, taking into account the timing / frequency control update period, based on the rate of change of the propagation delay and the rate of change of the Doppler shift at each instant of the satellite position, and outputs it to the data transmission processing unit 105. The TDW, which takes into account the timing / frequency control update period, includes, for example, instantaneous TDW, time-varying TDW, and TDW dependent on the satellite position. The TDW calculated by the control unit 103 is transmitted, for example, via a MAC CE.

[0085] The timing / frequency adjustment unit 104 calculates the transmission timing based on the reception timing output from the data reception processing unit 102 and the timing adjustment value output from the control unit 103, and outputs it to the wireless transmission unit 106. The timing / frequency adjustment unit 104 calculates the frequency correction value based on the Doppler shift information output from the control unit 103, and outputs it to the wireless transmission unit 106. The timing / frequency adjustment unit 104 does not update the transmission timing and / or frequency correction value (timing / frequency control updates) within the TDW interval output from the control unit 103, but rather updates the transmission timing and / or frequency correction value between TDW intervals. It should be noted that if the update can be performed while the phase shift meets the performance requirements, the timing / frequency control can be updated even within the TDW interval.

[0086] The data transmission processing unit 105 encodes the transmission data using LDPC or the like, performs modulation using QPSK or 16QAM or the like, adjusts the signal mapped to the time / frequency resource to the timing output from the timing / frequency adjustment unit 104 , and outputs it to the wireless transmission unit 106 .

[0087] LDPC stands for Low-Density Parity-Check code. QPSK stands for Quadrature Phase-Shift Keying. QAM stands for Quadrature Amplitude Modulation.

[0088] The data transmission processing unit 105 performs the same coding and modulation as described above, as well as time / frequency resource mapping, on the RRC message output from the control unit 103, which includes information on terminal capabilities related to TDW, and outputs the message to the wireless transmission unit 106. The data transmission processing unit 105 performs the same coding and modulation as described above, as well as time / frequency resource mapping, on the MAC CE output from the control unit 103, which includes TDW and takes into account the update period of timing / frequency control, and outputs the message to the wireless transmission unit 106.

[0089] In addition, the TDW taking into account the update period of the timing / frequency control may also be transmitted using higher layer signaling such as an RRC message or L1 signaling (low layer signaling) such as a PUCCH.

[0090] The wireless transmission unit 106 performs analog and digital transmission processing, such as D / A (Digital / Analog) conversion, filtering, upconversion, and amplification, on the signal output from the data transmission processing unit 105, and outputs the wireless signal to the antenna. The wireless transmission unit 106 performs timing adjustment and frequency correction (timing / frequency control) based on timing information such as TA information and frequency correction values ​​output from the timing / frequency adjustment unit 104.

[0091] It should be noted that the timing / frequency adjustment unit 104 can adjust both or one of the timing and frequency. The wireless transmission unit 106 can adjust both or one of the timing and frequency.

[0092] <<Structure of Base Station>>

[0093] Figure 5 This is a block diagram showing an example of the configuration of base station 200 according to Embodiment 1. Base station 200 includes a wireless reception unit 201 , a data reception processing unit 202 , a control unit 203 , a data transmission processing unit 204 , and a wireless transmission unit 205 .

[0094] The wireless reception unit 201 performs analog reception processing and digital reception processing such as down-conversion, A / D (Analog / Digital) conversion, and filtering on a signal received from the terminal 100 via the antenna, and outputs the signal to the data reception processing unit 202 .

[0095] The data reception processing unit 202 performs channel estimation and demodulation / decoding on uplink signals such as the PUSCH, PUCCH, and PRACH output from the wireless reception unit 201, obtaining a received data sequence. At this time, the data reception processing unit 202 performs joint channel estimation within the TDW interval set by the control unit 203. The data reception processing unit 202 outputs the RRC message and MAC CE data contained in the PUSCH to the control unit 203. For example, the RRC message includes information on terminal capabilities related to the TDW. For example, the MAC CE includes the TDW that takes into account the update period for timing / frequency control.

[0096] The control unit 203 generates system information (broadcast information) such as the Master Information Block (MIB) and the System Information Block (SIB), as well as control information such as terminal-specific RRC messages. System information includes, for example, NTN-specific information such as satellite ephemeris information, common TA parameters used in the terminal's TA, and epoch time. RRC messages include, for example, TDW setting information for the nominal TDW and information for enabling TDW notification for the terminal.

[0097] The control unit 203 generates DCI or PDCCH to accompany PDSCH transmission. DCI includes, for example, information related to PDSCH retransmission control such as NDI and RV, information related to the MCS of PDSCH and PUSCH, resource allocation information for PDSCH and PUSCH, and resource allocation information for PUCCH used for HARQ-ACK transmission for PDSCH.

[0098] DCI stands for Downlink Control Information. NDI stands for New Data Indicator. MCS stands for Modulation Coding Scheme. RV stands for Redundancy Version.

[0099] The control unit 203 may include TDW information such as the number of repeated transmissions (number of iterations) and the actual TDW in the resource allocation information. The control unit 203 may also notify the TDW information in the MAC CE. The control unit 203 outputs the set TDW to the data reception processing unit 202.

[0100] The data transmission processing unit 204 performs coding such as LDPC on the control information and transmission data output from the control unit 203 , performs modulation such as QPSK and 16QAM, and outputs the result to the wireless transmission unit 205 .

[0101] The wireless transmission unit 205 performs transmission processing such as D / A conversion, filtering, up-conversion, and amplification on the signal output from the data transmission processing unit 204 , and outputs the wireless signal to the antenna.

[0102] <Action Flow Example>

[0103] Figure 6 This is a flowchart illustrating an example operation of terminal 100 according to Embodiment 1. After performing initial access processing such as a RACH procedure (S1), terminal 100 notifies base station 200 of its terminal capabilities (S2). The terminal capabilities notified to base station 200 include, for example, information on a TDW capable of maintaining phase continuity and power consistency, taking into account the performance of hardware such as radio transmission unit 106 of terminal 100.

[0104] The terminal 100 receives the RRC reconfiguration message including the information of the nominal TDW ( S3 ).

[0105] The RRC reconfiguration message may include information for enabling TDW notification of terminal 100, a TDW notification cycle, and a TDW change threshold. The RRC reconfiguration message may also include information indicating whether TDW notification via DCI is to be performed.

[0106] Furthermore, terminal 100 sets the nominal TDW received in S3 as the DMRS bundled TDW and does not update the timing correction value and / or the frequency correction value (update of timing / frequency control) within the TDW so as not to cause a phase change exceeding a predetermined level.

[0107] The terminal 100 determines whether the RRC message received in S3 includes information for enabling TDW reporting ( S4 ).

[0108] When the RRC message received in S3 includes information for enabling TDW reporting ("Yes" in S4), the terminal 100 periodically reports TDW to the base station 200 (S5).

[0109] The reported TDW may be, for example, a TDW that satisfies timing and / or frequency performance requirements for satellite positions at the reporting time, taking into account the update period of timing / frequency control, or taking into account satellite movement.

[0110] The reporting period can be received from base station 200 via an RRC reset message. Reporting can also be non-periodic and event-triggered. For example, TDW reporting can be triggered when the change in TDW exceeds a predetermined threshold. Terminal 100 can also report TDW that takes into account the phase rotation of the base station's received signal caused by variations in propagation delay due to satellite movement.

[0111] When the RRC message received in S3 does not include information for enabling TDW reporting (No in S4), or after the report in S5, the terminal 100 determines whether the RRC message received in S3 includes information indicating TDW notification via DCI (S6).

[0112] When the RRC message received in S3 includes information indicating that TDW notification is to be performed via DCI (Yes in S6 ), terminal 100 sets the TDW for PUSCH transmission based on the TDW information included in the PDCCH (DCI) transmitted from base station 200 ( S7 Alternative (Alt) 1 ).

[0113] If the RRC message received in S3 does not include information indicating that TDW notification is to be performed via DCI ("No" in S6), terminal 100 sets the TDW reported by terminal 100 in S5 as the TDW for PUSCH transmission (S8 Alternative 2). Alternatively, terminal 100 sets the nominal TDW notified in the RRC message received from base station 200 in S3 as the TDW for PUSCH transmission (S8 Alternative 3).

[0114] In the above, an example of the operation of the terminal 100 has been described using the flowchart.

[0115] In addition, in the case of Alternative 1 of S7, for example, the following field of DCI may be used to notify TDW.

[0116] A new field is set in DCI format 0_1 ​​and / or DCI format 0_2 for allocating an uplink signal (eg, PUSCH) to notify TDW.

[0117] The interpretation of existing fields is changed (re-purposed) to notify TDW. For example, a portion of the bits in the MCS field is used to notify one of {M, M / 2, M / 4, M / 8} (M is the number of time slots of the nominal TDW). For example, the upper 2 bits of the 5-bit MCS field, that is, the bits indicating a larger MCS level or modulation multi-value number, are used to notify TDW. In addition, the terminal 100 can also use the lower bits of the MCS field to notify TDW. In the case where the terminal 100 is a terminal with low transmission output and antenna gain, such as a smartphone, it is effective to use the upper bits of the MCS field to cope with a wider coverage range because a low MCS can be used.

[0118] The TDRA (Time Domain Resource Allocation) field is used to notify the TDW together with the number of repetitions.

[0119] In addition, in the case of alternative 2 of S8, in order to make the TDW recognized by the terminal 100 and the base station 200 the same, the terminal 100 uses the new TDW (TDW reported in S5) notified to the base station 200 through the MAC CE for the PUSCH transmission scheduled by the DCI after time T shown in the following formula (2).

[0120] T = slot n + Kmac + 3ms (2)

[0121] In equation (2), slot n represents the PUSCH transmission slot number of the MAC CE containing the TDW report. Kmac represents the timing difference between the downlink and uplink at base station 200 (or reference location). Kmac is set by base station 200 to terminal 100. 3 ms is a time that takes into account the processing time of base station 200 and is an existing value used as the timing for reflecting the MAC CE. 3 ms is only an example and is not limited to this value.

[0122] exist Figure 6 In the flowchart, terminal 100 may perform any of alternatives 1 to 3 regardless of whether it receives an RRC message containing information indicating that TDW reporting is to be performed via DCI. Furthermore, the TDW used during PUSCH transmission may be the actual TDW. Alternatively, if the RRC message received in S3 does not contain information enabling TDW reporting ("No" in S4), terminal 100 may perform the processing of alternative 3.

[0123] <<Summary of Implementation Method 1>>

[0124] Even if the update period of the timing / frequency control varies with the movement of the satellite, the terminal 100 can report an appropriate TDW to the base station 200. In other words, the terminal 100 can report a TDW that takes the update period of the timing / frequency control into consideration to the base station 200.

[0125] Based on the TDW report from terminal 100, base station 200 can notify the terminal of an appropriate TDW corresponding to the movement of the satellite. Base station 200 can appropriately set the number of time slots used in joint channel estimation for reception, thereby improving channel estimation accuracy and error rate, throughput, and / or coverage performance.

[0126] The TDW information generated by the control unit of terminal 100 taking into account the update period of timing / frequency control may be information indicating the difference between the TDW capability of maintaining phase continuity and power consistency, or information indicating the difference between the TDW (e.g., nominal TDW) set by base station 200. Alternatively, the information may be information indicating the difference between the TDW information taking into account the update period of timing / frequency control reported previously.

[0127] <Implementation Method 2>

[0128] In Embodiment 2, the terminal reports the TDW (Time Division Multiplexing) of the timing / frequency control update period, which takes into account the change in the satellite's movement, to the base station as the terminal's capabilities. In other words, the terminal reports the time period during which phase continuity and power consistency can be maintained as the terminal's capabilities.

[0129] The base station estimates the interval in which phase continuity and power consistency of the uplink signal are maintained based on the TDW information included in the terminal capabilities notified from the terminal and the positional relationship between the satellite and the terminal, and determines the time slot for joint channel estimation.

[0130] <<Terminal Structure>>

[0131] The block structure of the terminal of the second embodiment is the same as Figure 4 The block structures are the same, but some of the functions of the blocks are different. The following describes the parts with different functions.

[0132] The control unit 103 outputs the TDW capability that can maintain phase continuity and power consistency to the data transmission processing unit 105. The TDW capability takes into account the performance of hardware such as the wireless transmission unit 106 and the update period of timing / frequency control to meet timing and / or frequency performance requirements as the satellite moves.

[0133] The update cycle of the timing / frequency control may vary depending on the activation or position of the satellite. Therefore, the control unit 103 reports the following TDW capabilities (terminal capabilities), for example.

[0134] Capability 1: Report the TDW as the terminal capability based on the maximum update period based on timing and frequency control taking into account the satellite orbit. The maximum update period is, for example, the update period when the satellite position is at the highest elevation angle in the orbit.

[0135] Capability 2: Reporting the TDW based on the shortest update period of timing / frequency control taking into account the satellite orbit as a terminal capability. The shortest update period is, for example, the update period when the satellite position is at the lowest elevation angle in orbit.

[0136] Capability 3: Report the TDW based on the average or median update period of timing and frequency adjustments that take into account satellite orbits as a terminal capability. The average or median update period of frequency adjustment is, for example, the update period when the elevation angle of the satellite position is average or central.

[0137] The control unit 103 may report at least one of capabilities 1 to 3 as the terminal capabilities. When reporting capabilities 1 to 3 as the terminal capabilities, the control unit 103 may not report the TDW (e.g., instantaneous TDW, time-varying TDW, and TDW dependent on satellite position) that takes into account the update period of timing / frequency control at each moment using the MAC CE.

[0138] <<Structure of Base Station>>

[0139] The block structure of the base station of embodiment 2 is the same as Figure 5 The block structures are the same, but some of the functions of the blocks are different. The following describes the parts with different functions.

[0140] The control unit 203 sets the number of time slots (TDW) used for joint channel estimation based on the terminal capability of TDW notified from the terminal 100, and outputs it to the data reception processing unit 202. At this time, the control unit 203 estimates the number of time slots for which the phase variation is within the allowable range, taking into account the current satellite position and the terminal position, and sets it as the TDW.

[0141] <<Summary of Implementation Method 2>>

[0142] The terminal 100 reports the TDW based on the update period of the timing / frequency control taking into account the satellite orbit as the terminal capability.

[0143] Based on the TDW reported from terminal 100, which takes into account the satellite orbit, base station 200 estimates the interval in which phase continuity and power consistency of the uplink signal are maintained, and determines the time slot for joint channel estimation. By improving channel estimation accuracy, base station 200 can improve error rate, throughput, and coverage performance.

[0144] <<Supplement>>

[0145] The base station 200 may also estimate the position of the terminal 100 based on the satellite's beam transmission angle and / or beam reception angle, or the reception timing from the terminal 100 .

[0146] Terminal 100 may also report satellite elevation angles, information related to timing and / or frequency changes caused by satellite movement, and information related to periodic updates of timing / frequency control to base station 200. Base station 200 may set TDW based on the information reported from terminal 100.

[0147] The base station 200 may also notify the terminal 100 of the set TDW in the same manner as in the first embodiment.

[0148] The terminal 100 may also report the terminal capabilities 1 to 3 described above to the base station 200 during initial access, for example, via a RACH or the like.

[0149] The TDW reported as the terminal capability may vary depending on the satellite orbit and position. Therefore, in addition to initial access, the terminal 100 may report the terminal capabilities of capabilities 1 to 3 to the base station 200 during handover or handover associated with a satellite change.

[0150] <Implementation Method 3>

[0151] In Embodiment 3, the terminal reports the TDW value based on the performance of hardware components such as the wireless transmission unit, i.e., the TDW without considering the effects of satellite motion, as the terminal capability (UE capability) to the base station. Alternatively, in addition to the performance of hardware components such as the wireless transmission unit, the terminal reports the TDW required to meet certain performance requirements (TDW conditions) related to timing and / or frequency (TDW that takes into account the update period for timing / frequency control) to the base station as the terminal capability. Which of these two parameters is to be reported can be determined by the specifications, or the base station can instruct which one to report.

[0152] The terminal corrects the phase rotation amount based on the propagation delay variation and / or Doppler shift variation caused by satellite movement according to the specification or the instruction of the base station, and transmits the PUSCH (data).

[0153] Based on the TDW conditions reported from the terminal and / or the presence or absence of corrections to the terminal's phase rotation, the base station sets the TDW, taking into account the satellite's orbit and position, and also sets the number of time slots used for joint channel estimation. The base station notifies the terminal of the set number of time slots (TDW). Alternatively, the base station estimates the phase rotation amount generated within the TDW based on the satellite's orbit and position, as well as the terminal's position, and performs joint channel estimation after correction.

[0154] The TDW conditions and the presence or absence of correction of the phase rotation amount in the terminal may be determined according to the specifications, may be instructed by the base station, or may be notified by the terminal as a terminal capability.

[0155] <<Terminal Structure>>

[0156] The block structure of the terminal of the third embodiment is the same as Figure 4 The block structures are the same, but some of the functions of the blocks are different. The following describes the parts with different functions.

[0157] The control unit 103 outputs the TDW based on the performance of the wireless transmission unit 106 to the data transmission processing unit 105 in accordance with specified specifications. In other words, the control unit 103 outputs the TDW to the data transmission processing unit 105 without taking into account the effects of timing and / or frequency corrections caused by satellite movement. Furthermore, in addition to the performance of the wireless transmission unit 106, the control unit 103 outputs the TDW (taking into account the update period of the timing / frequency control) required to meet certain performance specifications related to timing and / or frequency to the data transmission processing unit 105.

[0158] Based on an instruction from the base station 200, the control unit 103 may output to the data transmission processing unit 105 either or both of the TDW based on the performance of the wireless transmission unit 106 and the TDW that takes into account the update cycle of the timing / frequency control. The control unit 103 may also output to the data transmission processing unit 105 information indicating which TDW is reported as the terminal capability.

[0159] The control unit 103 outputs information indicating whether to correct the phase rotation amount due to the propagation delay variation and / or Doppler shift variation caused by satellite movement to the data transmission processing unit 105. This information may be included in the signal received from the base station 200.

[0160] The data transmission processing unit 105 performs transmission processing on the terminal capabilities of the TDW and / or information indicating which TDW is notified as the terminal capabilities, output from the control unit 103. When performing data transmission processing, the data transmission processing unit 105 corrects the phase rotation amount caused by satellite movement according to information output from the control unit 103 indicating whether the phase rotation amount should be corrected.

[0161] <<Structure of Base Station>>

[0162] The block structure of the base station of embodiment 3 is the same as Figure 5 The block structures are the same, but some of the functions of the blocks are different. The following describes the parts with different functions.

[0163] The control unit 203 sets the number of time slots (TDW) used for joint channel estimation based on the TDW condition and the TDW notified from the terminal 100, and outputs the set number of time slots to the data reception processing unit 202. The control unit 203 outputs information indicating whether to correct the phase rotation amount caused by propagation delay variation and / or Doppler shift variation due to satellite movement to the data reception processing unit 202.

[0164] The data reception processing unit 202 performs joint channel estimation according to the TDW output from the control unit 203. Alternatively, the data reception processing unit 202 may estimate the phase rotation amount generated within the TDW based on the satellite orbit and position, the terminal position, etc., according to the settings from the control unit 203, and perform joint channel estimation after correction.

[0165] In addition to the TDW terminal capabilities transmitted from terminal 100, data reception processing unit 202 also receives and processes information indicating the terminal capabilities of the TDW conditions. Data reception processing unit 202 also receives and processes information indicating whether the terminal should correct the phase rotation amount due to propagation delay variations and / or Doppler shift variations caused by satellite movement.

[0166] Data transmission processing unit 204 performs transmission processing of information regarding TDW conditions notified by terminal 100. This information is transmitted to terminal 100 via, for example, an SIB or a terminal-specific RRC message. Data transmission processing unit 204 performs transmission processing of information instructing terminal 100 to modify the phase rotation amount. This information is transmitted to the terminal via, for example, an SIB or a terminal-specific RRC message.

[0167] <<Action Example>>

[0168] Figure 7 This is a diagram for explaining an example of operations of the terminal 100 and the base station 200. Examples of the terminal capabilities notified by the terminal 100 include the following (1) to (4).

[0169] (1) Considering the TDW of HW

[0170] (2) TDW taking into account the update period of timing / frequency control used to meet certain performance requirements related to timing and / or frequency

[0171] (3) TDW, which takes into account the phase rotation caused by the propagation delay variation in the base station

[0172] (4) TDW taking into account the phase rotation caused by Doppler frequency fluctuations in the base station

[0173] Examples of functions implemented by the terminal 100 include the following (A).

[0174] (A) In the terminal, the phase rotation amount of (3) and (4) above is estimated to correct the uplink signal and send it (pre-compensate).

[0175] Examples of functions implemented by the base station 200 include the following (B-1) to (B-3).

[0176] (B-1) Do not perform the phase rotation amount corrections in (3) and (4) above, and perform joint channel estimation using the set TDW.

[0177] (B-2) The phase rotation amounts of (3) and (4) are estimated to correct the received signal (pre-compensation), and joint channel estimation is performed using the set TDW.

[0178] (B-3) Considering the phase rotation amounts of (3) and (4) above, the number of time slots (≤TDW) that can be used for joint channel estimation is estimated, and joint channel estimation is performed.

[0179] The terminal 100 and the base station 200 can also perform Figure 7 The actions 1 to 6 are shown.

[0180] In action 1, terminal 100 notifies base station 200 of (1) as a terminal capability. Terminal 100 notifies (2) and / or (3) using MAC CE. Terminal 100 may not have the function (A). Base station 200 has the function (B-1).

[0181] In action 2, terminal 100 notifies base station 200 of (1), (2), and (3) as terminal capabilities. Terminal 100 does not perform notifications of (1) to (4) using MAC CE. Terminal 100 may not have function (A). Base station 200 has function (B-2) or (B-3).

[0182] In action 3, terminal 100 notifies base station 200 of (1) above as terminal capability. Terminal 100 does not perform notifications (1) to (4) above using MAC CE. Terminal 100 may not have function (A) above. Base station 200 has function (B-2) or (B-3) above.

[0183] In Action 4, the terminal 100 notifies the base station 200 of (1) as the terminal capability. The terminal 100 does not perform the notifications (1) to (4) using the MAC CE. The terminal 100 has the function (A) above. The base station 200 has the function (B-1) above.

[0184] In action 5, terminal 100 notifies base station 200 of (1) and (2) above as terminal capabilities. Terminal 100 does not perform notifications (1) to (4) above using MAC CE. Terminal 100 may not have function (A) above. Base station 200 has function (B-2) or (B-3) above.

[0185] In Action 6, terminal 100 transmits (1) and (2) as terminal capabilities to base station 200. Terminal 100 does not perform notifications (1) to (4) using MAC CE. Terminal 100 has the function (A). Base station 200 has the function (B-1).

[0186] In addition, the base station 200 may also notify the terminal 100 of the following information.

[0187] Information about which TDW to report

[0188] Information about whether phase corrections related to timing and / or frequency variations caused by satellite movement are performed at the terminal

[0189] The terminal 100 may notify the base station 200 of the following information.

[0190] Information about which TDW was reported

[0191] Information about whether phase corrections related to timing and / or frequency variations caused by satellite movement are performed at the terminal

[0192] <<Summary of Implementation Method 3>>

[0193] The base station 200 can obtain information on the TDW that can be achieved by each terminal under predetermined conditions determined by the specification or instructed by the terminal, and can therefore perform joint channel estimation using an appropriate number of time slots depending on the terminal.

[0194] The base station 200 notifies the base station 200 of the TDW, along with the TDW, information indicating the conditions under which the TDW reported by the terminal to the base station 200 is the TDW. This allows the base station 200 to identify the processing performed by the terminal 100 to transmit the PUSCH (for example, whether phase changes caused by time variations in the propagation path or Doppler frequency variations are corrected), even when the timing / frequency control and phase correction processing implemented by the terminal 100 are different. This allows the base station 200 to perform joint channel estimation using an appropriate number of time slots.

[0195] The base station 200 can correct the phase rotation amount without the terminal 100 correcting the phase rotation amount caused by the propagation delay variation and / or Doppler shift variation due to the movement of the satellite, and thus can perform appropriate phase correction.

[0196] The embodiment has been described above.

[0197] In the present disclosure, the TDW that takes into account HW performance and satellite movement and that a terminal reports as terminal capabilities may be TDW that meets the performance requirements of Rel. 17. For example, the performance requirements may be defined by the amount of phase change allowed between two time slots and between arbitrary time slots.

[0198] In addition, although it is recorded that the transmission timing and / or frequency correction value are not updated (timing / frequency control update) in the TDW interval, the timing can be changed if the timing can be changed while the phase variation meets the performance requirements.

[0199] One embodiment of the present disclosure can be used for different types of satellite communications, such as low-Earth orbit satellites (LEO), medium-Earth orbit satellites (MEO), high-Earth orbit satellites (HEO), or geostationary satellites (GEO). For example, the information indicating the relationship between the distance between terminal 100 and the satellite and the initial access resource (e.g., PRACH sequence or repetition number) in Embodiments 1 and 2, and the information indicating the relationship between the TA value and the initial access resource (e.g., PRACH sequence or repetition number) in Embodiment 3 can be separately set according to the satellite type (or satellite altitude).

[0200] In each of the above embodiments, satellite ephemeris information, which is information related to satellite positions, may be broadcast via system information or may be pre-stored in terminal 100. Furthermore, satellite ephemeris information may be updated when communication is possible. Furthermore, terminal 100 may use information other than satellite ephemeris information to determine satellite positions.

[0201] Furthermore, while the above embodiments describe examples using GNSS such as GPS (e.g., position detection using satellite signals), the present invention is not limited thereto. For example, position detection using terrestrial cellular base stations, using WiFi (registered trademark) signals or Bluetooth (registered trademark) signals, using an accelerometer, or a combination of these detection methods may also be performed. Furthermore, altitude information may be obtained from a barometric pressure sensor or the like.

[0202] In each of the above embodiments, the base station may be replaced by a network or a RAN (Radio Access Network). Reporting may be replaced by notification, and notification may be replaced by reporting. Calculation may be replaced by determination or generation. As described above, TDW includes nominal TDW and actual TDW. In the present disclosure, when only "TDW" is recorded, it may be interpreted as both or one of the nominal TDW and actual TDW, depending on the context. Alternatively, it may be interpreted as the number of time slots used by the base station in the JCE. The performance of the HW may also include processors such as a CPU (Central Processing Unit) and a DSP (Digital Signal Processor) that execute programs. The performance of the HW may be interchangeable with the performance of the terminal.

[0203] Furthermore, in the above-described embodiments, an example of using DMRS bundling for uplink signals from a terminal to a base station has been described. However, the present invention can also be applied to a case where DMRS bundling is used for downlink signals from a base station to a terminal.

[0204] In addition, an embodiment of the present disclosure can be applied regardless of the type of satellite, such as GEO, MEO, LEO, or HEO. In addition, an embodiment of the present disclosure can also be applied to non-terrestrial communications such as HAPS or drone base stations.

[0205] In addition, although the above embodiments are described using an NTN environment (e.g., a satellite communication environment), the present disclosure is not limited thereto. The present disclosure may also be applied to other communication environments (e.g., at least one terrestrial cellular environment in LTE and NR). For example, an embodiment of the present disclosure may also be applied to terrestrial communications in an environment where, for example, the cell size is large and the propagation delay between the base station 200 and the terminal 100 is longer (e.g., above a threshold).

[0206] In addition, in the above-mentioned embodiments, the satellite communication method may be a structure in which the base station functions are located on a satellite (for example, a "regenerative satellite"), or a structure in which the base station functions are located on the ground, and the satellite relays the communication between the base station and the terminal (for example, a "transparent satellite"). For example, in one embodiment of the present disclosure, the downlink and uplink may also be links between the terminal and the satellite, or links via the satellite.

[0207] In addition, the method of notifying the terminal 100 of control information from the base station 200 is not limited to the above example. It can be notified (or broadcast, indicated, set) by at least one of system information such as MIB and SIB, RRC control information, MAC control information and downlink control information (DCI: Downlink Control Information), or it can be pre-set to the terminal 100, or it can be pre-specified in the standard.

[0208] A base station may be referred to as a “gNodeB” or a “gNB.” A terminal may also be referred to as a “UE.”

[0209] Time resource units such as system frames and subframes may also be replaced by time slots, time slots, mini-slots, frames, subframes, and the like.

[0210] In addition, the expression "......part" in the above embodiments may be replaced by other expressions such as "......circuitry", "......device", "......unit" or "......module".

[0211] (Replenish)

[0212] The information indicating whether the terminal 100 supports the functions, actions, or processes described in the above embodiments may be sent (or notified) by the terminal 100 to the base station 200 as capability information or capability parameters of the terminal 100 , for example.

[0213] The capability information may also include the following information elements (IE: Information Element), each of which individually indicates whether the terminal 100 supports at least one of the functions, actions, and processes described in the above embodiments. Alternatively, the capability information may also include the following information elements, each of which indicates whether the terminal 100 supports a combination of two or more of the functions, actions, and processes described in the above embodiments.

[0214] For example, based on the capability information received from the terminal 100, the base station 200 can determine (or decide or assume) the functions, actions, or processes supported (or not supported) by the terminal 100 that sent the capability information. The base station 200 can perform actions, processes, or controls corresponding to the determination result based on the capability information. For example, the base station 200 can control communications for the NTN based on the capability information received from the terminal 100.

[0215] It should be noted that the fact that the terminal 100 does not support some of the functions, actions, or processes described in the above embodiments may also mean that such some functions, actions, or processes are restricted in the terminal 100. For example, information or a request related to such restrictions may also be notified to the base station 200.

[0216] Information related to the capabilities or limitations of the terminal 100 may be defined in a standard, for example, or may be implicitly notified to the base station 200 by being associated with information known to the base station 200 or information transmitted to the base station 200 .

[0217] (Control Signal)

[0218] In the present disclosure, a downlink control signal (or downlink control information) associated with an embodiment of the present disclosure may be, for example, a signal (or information) transmitted in a physical downlink control channel (PDCCH) at the physical layer, or a signal (or information) transmitted in a medium access control element (MAC CE) or radio resource control (RRC) at a higher layer. Furthermore, the signal (or information) is not limited to being notified via a downlink control signal and may be pre-defined in a specification (or standard) or pre-configured in a base station or terminal.

[0219] In the present disclosure, an uplink control signal (or uplink control information) associated with an embodiment of the present disclosure may be, for example, a signal (or information) transmitted in the PUCCH of the physical layer, or a signal (or information) transmitted in the MAC CE or RRC of a higher layer. Furthermore, the signal (or information) is not limited to being notified by an uplink control signal, and may be pre-defined in a specification (or standard), or may be pre-set in a base station and a terminal. Furthermore, the uplink control signal may be, for example, replaced with uplink control information (UCI), first stage sidelink control information (SCI), or second stage SCI.

[0220] (Base Station)

[0221] In one embodiment of the present disclosure, a base station may also be a Transmission Reception Point (TRP), a cluster head, an access point, a Remote Radio Head (RRH), an eNodeB (eNB), a gNodeB (gNB), a Base Station (BS), a Base Transceiver Station (BTS), a master station, a gateway, or the like. Furthermore, in sidelink communications, a terminal may also function as a base station. Furthermore, a relay device that relays communications between a higher-level node and a terminal may replace a base station. Furthermore, a roadside device may replace a base station.

[0222] (Uplink / Downlink / Sidelink)

[0223] An embodiment of the present disclosure can be applied to any link in the uplink, downlink, and sidelink. For example, an embodiment of the present disclosure can also be applied to the physical uplink shared channel (PUSCH), physical uplink control channel (PUCCH), physical random access channel (PRACH) of the uplink, the physical downlink shared channel (PDSCH), PDCCH, physical broadcast channel (PBCH) of the downlink, or the physical sidelink shared channel (PSSCH), physical sidelink control channel (PSCCH), physical sidelink broadcast channel (PSBCH) of the sidelink.

[0224] It should be noted that PDCCH, PDSCH, PUSCH, and PUCCH are examples of downlink control channels, downlink data channels, uplink data channels, and uplink control channels, respectively. Furthermore, PSCCH and PSSCH are examples of sidelink control channels and sidelink data channels, respectively. PBCH and PSBCH are examples of broadcast channels, and PRACH is an example of a random access channel.

[0225] (Data channel / Control channel)

[0226] An embodiment of the present disclosure can be applied to any of the data channels and control channels. For example, the channel in an embodiment of the present disclosure can be replaced with one of the PDSCH, PUSCH, and PSSCH of the data channel, or the PDCCH, PUCCH, PBCH, PSCCH, and PSBCH of the control channel.

[0227] (Reference signal)

[0228] In one embodiment of the present disclosure, a reference signal is, for example, a signal known to both the base station and the mobile station, and is sometimes also referred to as a "reference signal (RS)" or a "pilot signal." A reference signal can be any of the following: a demodulation reference signal (DMRS), a channel state information-reference signal (CSI-RS), a tracking reference signal (TRS), a phase tracking reference signal (PTRS), a cell-specific reference signal (CRS), and a sounding reference signal (SRS).

[0229] (Time interval)

[0230] In one embodiment of the present disclosure, the unit of time resources is not limited to one of a time slot and a symbol, or a combination thereof. For example, it may be a time resource unit such as a frame, a superframe, a subframe, a time slot, a time slot, a subslot, a minislot, or a symbol, an Orthogonal Frequency Division Multiplexing (OFDM) symbol, or a Single Carrier-Frequency Division Multiplexing Access (SC-FDMA) symbol, or other time resource units. In addition, the number of symbols contained in one time slot is not limited to the number of symbols exemplified in the above embodiment, and may be other numbers of symbols.

[0231] (frequency band)

[0232] One embodiment of the present disclosure may be applied to any of licensed bands and unlicensed bands.

[0233] (communication)

[0234] An embodiment of the present disclosure can be applied to any communication between a base station and a terminal (Uu link communication), between terminals (sidelink communication), or in vehicle-to-everything (V2X) wireless communication. For example, the channel in an embodiment of the present disclosure can be replaced with one of the following: PSCCH, PSSCH, Physical Sidelink Feedback Channel (PSFCH), PSBCH, PDCCH, PUCCH, PDSCH, PUSCH, and PBCH.

[0235] Furthermore, an embodiment of the present disclosure can be applied to either terrestrial networks or non-terrestrial networks (NTNs) using satellites or high-altitude pseudo-satellites (HAPSs). Furthermore, an embodiment of the present disclosure can be applied to terrestrial networks with transmission delays greater than the symbol length or slot length, such as networks with large cell sizes and ultra-wideband transmission networks.

[0236] (Antenna port)

[0237] In one embodiment of the present disclosure, an antenna port refers to a logical antenna (antenna group) composed of one or more physical antennas. For example, an antenna port does not necessarily refer to a single physical antenna, but may refer to an array antenna composed of multiple antennas. For example, an antenna port may not be defined as consisting of a number of physical antennas, but may be defined as the minimum unit by which a terminal can transmit a reference signal (reference signal). In addition, an antenna port is sometimes defined as the minimum unit by which a weighted precoding vector is multiplied.

[0238] 5G NR System Architecture and Protocol Stack

[0239] 3GPP is continuing work on the next version of fifth-generation mobile technology (also known as "5G"), including the development of new radio access technology (NR) operating in the frequency range up to 100 GHz. The first version of the 5G standard was completed in late 2017, enabling the transition to trial production and commercial deployment of devices (e.g., smartphones) compliant with the 5G NR standard.

[0240] For example, the overall system architecture envisions an NG-RAN (Next Generation Radio Access Network) consisting of gNBs. The gNBs provide UE-side termination of the user plane (SDAP (Service Data Adaptation Protocol) / PDCP (Packet Data Convergence Protocol) / RLC (Radio Link Control) / MAC / PHY (Physical Layer)) and control plane (RRC) protocols of the NG radio access. gNBs are connected to each other via the Xn interface. Furthermore, gNBs are connected to the Next Generation Core (NGC) via the Next Generation (NG) interface, more specifically, to the Access and Mobility Management Function (AMF) (e.g., a core entity that implements the AMF) via the NG-C interface, and to the User Plane Function (UPF) (e.g., a core entity that implements the UPF) via the NG-U interface. Figure 8 Represents the NG-RAN architecture (for example, refer to 3GPP TS 38.300 v15.6.0, section 4).

[0241] The NR user plane protocol stack (e.g., see 3GPP TS 38.300, Section 4.4.1) includes the PDCP (Packet Data Convergence Protocol) sublayer (see Section 6.4 of TS 38.300), the RLC (Radio Link Control) sublayer (see Section 6.3 of TS 38.300), and the MAC (Media Access Control) sublayer (see Section 6.2 of TS 38.300), which terminates on the network side in the gNB. Furthermore, a new access stratum (AS) sublayer (SDAP: Service Data Adaptation Protocol) has been introduced on top of PDCP (e.g., see Section 6.5 of 3GPP TS 38.300). Furthermore, a control plane protocol stack has been defined for NR (e.g., see Section 4.4.2 of TS 38.300). An overview of Layer 2 functionality is provided in Section 6 of TS 38.300. The functions of the PDCP sublayer, RLC sublayer, and MAC sublayer are listed in Sections 6.4, 6.3, and 6.2 of TS 38.300, respectively. The functions of the RRC layer are listed in Section 7 of TS 38.300.

[0242] For example, the media access control layer handles multiplexing of logical channels, scheduling including processing of various parameter sets, and various functions associated with the scheduling.

[0243] For example, the physical layer (PHY) is responsible for coding, PHY HARQ (Physical Layer Hybrid Automatic Repeat Request) processing, modulation, multi-antenna processing, and mapping signals to appropriate physical time-frequency resources. In addition, the physical layer handles the mapping of transport channels to physical channels. The physical layer provides services to the MAC layer in the form of transport channels. A physical channel corresponds to a set of time-frequency resources used to send a specific transport channel, and each transport channel is mapped to a corresponding physical channel. For example, among physical channels, uplink physical channels include PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), and PUCCH (Physical Uplink Control Channel), and downlink physical channels include PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel), and PBCH (Physical Broadcast Channel).

[0244] The use cases / extended scenarios of NR may include enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine type communications (mMTC), which have various requirements in terms of data rate, latency, and coverage. For example, eMBB is expected to support peak data rates (20 Gbps in downlink and 10 Gbps in uplink) and effective (user-experienced) data rates that are about three times the data rates provided by IMT-Advanced (International Mobile Telecommunications-Advanced). On the other hand, in the case of URLLC, more stringent requirements are proposed for ultra-low latency (the latency of the user plane is 0.5 ms in UL and DL respectively) and high reliability (1-10-5 within 1 ms). Finally, in mMTC, preferably, a high connection density is required (1,000,000 devices / km in urban environments). 2 ), wide coverage in harsh environments and extremely long battery life (15 years) for an inexpensive device.

[0245] Therefore, sometimes the OFDM parameter set (e.g., subcarrier spacing (SCS), OFDM symbol length, cyclic prefix (CP) length, number of symbols per scheduling interval) that is suitable for one use case is not valid for other use cases. For example, in low-latency services, it is preferred that the symbol length is shorter than that of mMTC services (therefore, the subcarrier spacing is larger) and / or the number of symbols per scheduling interval (also known as "TTI (Transmission Time Interval)") is smaller. Moreover, in extended scenarios where the channel delay spread is large, it is preferred that the CP length is longer than that in scenarios where the delay spread is short. The subcarrier spacing can also be optimized according to the situation to maintain the same CP overhead. The subcarrier spacing supported by NR can have more than one value. Correspondingly, subcarrier spacings of 15kHz, 30kHz, 60kHz... are currently considered. The symbol length Tu and the subcarrier spacing Δf are directly related according to the formula Δf=1 / Tu. Similar to the LTE system, the term “resource element” can be used to represent the minimum resource unit consisting of one subcarrier with a length of one OFDM / SC-FDMA (Single-Carrier Frequency Division Multiple Access) symbol.

[0246] In the new wireless system 5G-NR, a resource grid of subcarriers and OFDM symbols is defined for each numerology set and each carrier in both the uplink and downlink. Each element of the resource grid is called a "resource element" and is identified by a frequency index in the frequency domain and a symbol position in the time domain (see 3GPP TS 38.211 v15.6.0).

[0247] Functional separation between NG-RAN and 5GC in 5G NR

[0248] Figure 9 This indicates the functional separation between NG-RAN and 5GC. The logical node of NG-RAN is the gNB or ng-eNB. The 5GC has the logical nodes AMF, UPF, and SMF (Session Management Function).

[0249] For example, gNB and ng-eNB host the following key functions:

[0250] - Radio bearer control (RBC), radio admission control (RAC), connection mobility control (CMC), and radio resource management (RRM) functions, such as dynamically allocating (scheduling) resources to UEs in both uplink and downlink;

[0251] - IP (Internet Protocol) header compression, encryption, and integrity protection of data;

[0252] - Selection of the AMF upon attaching the UE in case the routing towards the AMF cannot be decided based on the information provided by the UE;

[0253] - Routing of user plane data towards the UPF;

[0254] - Routing of control plane information towards the AMF;

[0255] -Setting up and disconnecting connections;

[0256] - Scheduling and sending of paging messages;

[0257] - Scheduling and sending of system broadcast information (AMF or Operation, Admission, Maintenance (OAM) function as the originator);

[0258] - Settings for measurements and measurement reports for mobility and scheduling;

[0259] - Packet marking of transmission class in uplink;

[0260] -Session management;

[0261] - Network slicing support;

[0262] -QoS (Quality of Service) flow management and mapping to data radio bearers;

[0263] - Support for UEs in RRC_INACTIVE (RRC inactive) state;

[0264] -NAS (Non Access Stratum) message distribution function;

[0265] -Sharing of wireless access networks;

[0266] -Dual connection;

[0267] -Close collaboration between NR and E-UTRA (Evolved Universal Terrestrial Radio Access).

[0268] The Access and Mobility Management Function (AMF) hosts the following main functions:

[0269] - Functionality to terminate Non-Access Stratum (NAS) signaling;

[0270] -Security of NAS signaling;

[0271] -Security control of the access layer (AS);

[0272] -Core Network (CN) inter-node signaling for mobility between 3GPP access networks;

[0273] - the possibility of reaching the UE in idle mode (including the control and execution of paging retransmission);

[0274] - Management of the registration area;

[0275] -Support for intra-system and inter-system mobility;

[0276] -Access authentication;

[0277] - Access permission including roaming permission check;

[0278] -Mobility management control (subscription and policy);

[0279] - Network slicing support;

[0280] - Selection of Session Management Function (SMF).

[0281] In addition, the User Plane Function (UPF) hosts the following main functions:

[0282] - Anchor point for intra-RAT (Radio Access Technology) mobility / inter-RAT (Inter-RAT) mobility (where applicable);

[0283] - External PDU (Protocol Data Unit) session point for interconnection with data networks;

[0284] -Packet routing and forwarding;

[0285] - Packet inspection and policy rule enforcement in the user plane;

[0286] - Business usage reports;

[0287] - Uplink classifier for supporting routing of traffic towards the data network;

[0288] -BranchingPoint used to support multi-homed PDU session;

[0289] - QoS processing for the user plane (e.g., packet filtering, gating, UL / DL rate enforcement);

[0290] - Verification of uplink services (mapping of SDF (Service Data Flow) to QoS flows);

[0291] - Downlink packet buffering and downlink data notification triggering function.

[0292] Finally, the Session Management Function (SMF) hosts the following main functions:

[0293] -Session management;

[0294] -Allocation and management of UE IP addresses;

[0295] - UPF selection and control;

[0296] - Traffic steering configuration function in the user plane function (UPF) for directing traffic to the appropriate destination;

[0297] - Enforcement of policies and QoS in the control part;

[0298] -Notification of downlink data.

[0299] <RRC connection setup and re-setup process>

[0300] Figure 10 Represents several interactions between the UE, gNB and AMF (5GC entity) when the UE transitions from RRC_IDLE (RRC Idle) to RRC_CONNECTED (RRC Connected) in the NAS part (refer to TS 38.300 v15.6.0).

[0301] RRC is a high-layer signaling (protocol) used for the configuration of the UE and gNB. Through this transition, the AMF prepares UE context data (including, for example, PDU session context, security keys, UE radio capabilities, UE security capabilities, etc.) and sends it to the gNB along with the initial context setup request (INITIAL CONTEXT SETUP REQUEST). Next, the gNB and the UE activate AS security. The gNB sends a SecurityModeCommand message to the UE, and the UE responds to the gNB with a SecurityModeComplete message, thereby activating AS security. The gNB then sends an RRCReconfiguration message to the UE, and the gNB receives an RRCReconfigurationComplete message from the UE in response to the RRCReconfiguration message, thereby reconfiguring the Signaling Radio Bearer 2 (SRB2) and Data Radio Bearer (DRB). For signaling-only connections, since SRB2 and DRB are not configured, the steps related to RRC reconfiguration can be omitted. Finally, the gNB notifies the AMF of the completion of the setup process using the Initial Context Setup Response (INITIAL CONTEXT SETUP RESPONSE).

[0302] Therefore, the present disclosure provides the following fifth-generation core network (5GC) entity (e.g., AMF, SMF, etc.), which includes: a control circuit that, when operating, establishes a next-generation (NG) connection with a gNodeB; and a transmitter that, when operating, sends an initial context setup message to the gNodeB via the NG connection to set up a signaling radio bearer between the gNodeB and a user equipment (UE). Specifically, the gNodeB sends radio resource control (RRC) signaling including a resource allocation setup information element (IE) to the UE via the signaling radio bearer. The UE then transmits in the uplink or receives in the downlink based on the resource allocation setup.

[0303] IMT Utilization Scenarios After 2020

[0304] Figure 11Indicates several use cases for 5G NR. In the 3rd Generation Partnership Project New Radio (3GPP NR), three use cases supporting a wide range of services and applications, as envisioned by IMT-2020, have been studied. The first phase of specification development for high-capacity, high-speed communications (eMBB: enhanced mobile broadband) has been completed. Current and future work includes the gradual expansion of support for eMBB and the standardization of ultra-reliable and low-latency communications (URLLC: ultra-reliable and low-latency communications) and multi-machine-type communications (mMTC: massive machine-type communications). Figure 11 Several examples of conceptual use cases for IMT after 2020 (for example, see ITU-R M.2083) Figure 2 ).

[0305] The use cases of URLLC have strict requirements related to performance such as throughput, latency (delay) and availability. The use cases of URLLC are conceived as an element technology for realizing future applications such as wireless control of industrial production processes or manufacturing processes, remote medical surgery, automation of power transmission and distribution in smart grids, and traffic safety. The ultra-high reliability of URLLC is supported by determining technologies that meet the requirements set by TR38.913. In the NR URLLC version 15, as an important requirement, the requirement that the target user plane latency is 0.5ms in UL (uplink) and 0.5ms in DL (downlink) is included. The overall URLLC requirement for a packet transmission is a block error rate (BLER) of 1E-5 for a packet size of 32 bytes with a user plane latency of 1ms.

[0306] Considering the physical layer, there are a number of possible approaches to improve reliability. Current scope for improving reliability includes defining additional CQI (Channel Quality Indicator) tables for URLLC, more compact DCI formats, PDCCH iteration, etc. However, as NR (an important prerequisite for NR URLLC) becomes more stable and receives further development, this scope can be expanded to achieve ultra-high reliability. Specific use cases for NR URLLC in Release 15 include augmented reality / virtual reality (AR / VR), e-health, e-safety, and critical applications.

[0307] In addition, the technical enhancements to the goals of NR URLLC are aimed at improving latency and increasing reliability. Technical enhancements for improving latency include configurable parameter sets, non-slot-based scheduling with flexible mapping, unauthorized (authorized) uplinks, slot-level repetitions in data channels, and preemption in downlinks. Preemption means stopping the transmission of allocated resources and using the allocated resources for other transmissions that are requested later and must meet the necessary conditions for lower latency / higher priority. Therefore, the transmission that has been allowed will be replaced by the subsequent transmission. Preemption can be applied regardless of the specific service type. For example, the transmission of service type A (URLLC) can also be replaced by the transmission of service type B (eMBB, etc.). Technical enhancements related to improving reliability include a dedicated CQI / MCS table for a target BLER of 1E-5.

[0308] mMTC (Massive Machine Type Communications) use cases typically involve a large number of connected devices transmitting relatively small amounts of data that are less susceptible to latency. These devices are required to be low-priced and have very long battery life. From the perspective of NR, utilizing very narrow bandwidth segments is one approach to conserving UE power and extending battery life.

[0309] As mentioned above, it is predicted that the room for reliability improvement in NR will be further expanded. It is one of the important requirements for all situations. For example, the important requirement related to URLLC and mMTC is high reliability or ultra-high reliability. From the perspective of wireless and the perspective of the network, reliability can be improved in several mechanisms. In general, there are two to three important areas that may help improve reliability. These areas include compact control channel information, repetition of data channels / control channels, and diversity related to frequency domain, time domain and / or spatial domain. These areas can be used universally to improve reliability regardless of the specific communication scenario.

[0310] Regarding NR URLLC, further use cases with more stringent requirements are envisioned, such as factory automation, transportation, and power transmission. Strict requirements include high reliability (up to 10 -6 level of reliability), high availability, packet sizes up to 256 bytes, time synchronization up to a few microseconds (μs) (capable of being set to 1 μs or a few microseconds depending on the use case, depending on the frequency range and short latency of around 0.5ms to 1ms (for example, 0.5ms latency in the user plane as the target).

[0311] Moreover, regarding NR URLLC, from the perspective of the physical layer, there may be several technical enhancements. These technical enhancements include the enhancement of PDCCH (Physical Downlink Control Channel) related to compact DCI, repetition of PDCCH, and increased monitoring of PDCCH. In addition, the enhancement of UCI (Uplink Control Information) is related to the enhancement of enhanced HARQ (Hybrid Automatic Repeat Request) and CSI feedback. In addition, there may be enhancement of PUSCH related to frequency hopping at the mini-slot level and enhancement of retransmission / repetition. The term "mini-slot" refers to a transmission time interval (TTI) that contains fewer code elements than a time slot (a time slot has 14 code elements).

[0312] QoS Control

[0313] The 5G QoS (Quality of Service) model is based on QoS flows, supporting both QoS flows that require guaranteed bit rates (GBR: Guaranteed Bit Rate QoS flows) and QoS flows that do not (non-GBR QoS flows). Therefore, at the NAS level, a QoS flow is the most granular QoS division within a PDU session. A QoS flow is identified within a PDU session by the QoS Flow ID (QFI: QoS Flow ID) transmitted in the encapsulation header via the NG-U interface.

[0314] For each UE, 5GC establishes one or more PDU sessions. For each UE, in conjunction with the PDU session, NG-RAN, for example, as described in the previous reference Figure 10 As described, at least one data radio bearer (DRB) is established. Additionally, DRBs added to the QoS flows of this PDU session may be configured later (when this is configured depends on the NG-RAN). The NG-RAN maps packets belonging to various PDU sessions to various DRBs. NAS-level packet filters in the UE and 5GC are used to associate UL and DL packets with QoS flows, and AS-level mapping rules in the UE and NG-RAN associate UL and DL QoS flows with DRBs.

[0315] Figure 12 Indicates the non-roaming reference architecture of 5G NR (refer to TS 23.501 v16.1.0, section 4.23). Application Function (AF) (e.g., host Figure 11The 5G service is an external application server for the 5G service illustrated in the example, which interacts with the 3GPP core network to provide services. For example, the network exposure function (NEF) is accessed to support applications that affect the routing of the service, or the policy framework is interacted with for policy control (for example, QoS control) (see Policy Control Function (PCF)). Based on the operator's deployment, the operator considers that the application function that is trusted can interact directly with the associated network function (Network Function). Application functions that are not allowed by the operator to directly access the network function interact with the associated network function via the NEF using an open framework to the outside world.

[0316] Figure 12 It also represents further functional units of the 5G architecture, namely, the Network Slice Selection Function (NSSF), the Network Repository Function (NRF), the Unified Data Management (UDM), the Authentication Server Function (AUSF), the Access and Mobility Management Function (AMF), the Session Management Function (SMF), and the Data Network (DN, e.g., services provided by an operator, Internet access, or services provided by a third party). All or part of the core network functions and application services may also be deployed and operated in a cloud computing environment.

[0317] Therefore, the present disclosure provides the following application server (for example, AF of 5G architecture), which includes: a sending unit, which, in action, sends a request containing QoS requirements for at least one of URLLC service, eMMB service and mMTC service to at least one of the functions of 5GC (for example, NEF, AMF, SMF, PCF, UPF, etc.) in order to establish a PDU session of wireless bearer between g-node B and UE corresponding to QoS requirements; and a control circuit, which, in action, uses the established PDU session to provide service.

[0318] The present disclosure can be implemented by software, hardware, or software in collaboration with hardware. The functional blocks used in the description of the above embodiments are partially or entirely implemented as LSIs (Large Scale Integration) as integrated circuits, and the processes described in the above embodiments may also be partially or entirely controlled by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip in a manner that includes part or all of the functional blocks. The LSI may also include data input and output. Depending on the degree of integration, the LSI may also be referred to as an "IC (Integrated Circuit)", "System LSI", "Super LSI", or "Ultra LSI".

[0319] Integrated circuit implementation is not limited to LSIs; it can also be implemented using dedicated circuits, general-purpose processors, or dedicated processors. Alternatively, FPGAs (Field Programmable Gate Arrays), which can be programmed after LSI fabrication, or reconfigurable processors (RPs), which allow reconfiguration of the connections and settings of circuit blocks within the LSI, can be utilized. The present disclosure can also be implemented as digital or analog processing.

[0320] Furthermore, if semiconductor technology advances or other technologies evolve and a technology for integrated circuits emerges that replaces LSIs, it would be possible to use this technology to integrate functional blocks. There is also the possibility of applying biotechnology, etc.

[0321] The present disclosure can be implemented in all types of devices, equipment, and systems (collectively referred to as "communication devices") that have communication capabilities. A communication device may also include a wireless transceiver and processing / control circuitry. The wireless transceiver may also include a receiving unit and a transmitting unit, or perform the functions of these units. The wireless transceiver (transmitting unit, receiving unit) may also include an RF (Radio Frequency) module and one or more antennas. The RF module may also include an amplifier, an RF modulator / demodulator, or similar devices. Non-limiting examples of communication devices include: telephones (mobile phones, smartphones, etc.), tablet computers, personal computers (PCs) (laptops, desktops, notebook computers, etc.), cameras (digital cameras, digital video cameras, etc.), digital players (digital audio / video players, etc.), wearable devices (wearable cameras, smart watches, tracking devices, etc.), game consoles, e-book readers, telehealth / telemedicine (telehealth / medical prescription) devices, vehicles or transportation vehicles with communication capabilities (cars, airplanes, ships, etc.), and combinations of the above devices.

[0322] Communication devices are not limited to portable or mobile devices. They also include all types of devices, equipment, and systems that cannot be portable or fixed. Examples include smart home devices (such as appliances, lighting, smart meters or meters, control panels, etc.), vending machines, and all other "things" that can exist on an IoT (Internet of Things) network.

[0323] Communication includes data communication via a cellular system, a wireless LAN (Local Area Network) system, a communication satellite system, etc., as well as data communication via a combination of these systems.

[0324] Furthermore, the communication device also includes devices such as controllers and sensors that are connected or coupled to the communication equipment performing the communication functions described in the present invention. For example, the communication device may include a controller or sensor that generates control signals or data signals used by the communication equipment performing the communication functions of the communication device.

[0325] In addition, the communication device includes infrastructure equipment that communicates with or controls the above-mentioned non-limiting various devices, such as base stations, access points, and all other devices, equipment, and systems.

[0326] As shown in the following notes, in order to meet the timing accuracy and phase continuity requirements, the terminal reports TDW according to the update period required for timing pre-compensation accompanying the movement of the satellite.

[0327] <Note 1>

[0328] In addition to reporting terminal capabilities, a terminal may also report TDW. The base station configures the terminal so that the terminal reports TDW via MAC CE.

[0329] The terminal reports possible TDWs via MAC CE, for example, 1, 2, 4, 8, 16, and 32. The terminal reports possible TDWs in response to an event trigger, for example, when a change in TDW reaches a certain value, or periodically.

[0330] The terminal may determine the TDW according to the following alternatives 1 to 3.

[0331] Alternative Solution 1: The terminal determines the actual TDW by DCI indication. The base station indicates the actual TDW through the DCI scheduling the PUSCH. Here, Alternative Solution 1 is further based on Alternative Solutions 1-1 to 1-3.

[0332] Alternative solution 1-1: Use a newly added field to indicate the actual TDW. For example, a newly added 5-bit field is used to indicate the actual TDW of 1, 2, 4, 8, 16, or 32.

[0333] Alternative 1-2: Reuse existing fields to indicate the actual TDW. For example, the upper or lower two bits of the MCS field can indicate {M, M / 2, M / 4, M / 8}, where M is the configured TDW value.

[0334] Alternative 1-3: The actual TDW is indicated together with the iteration factor of the TDRA table.

[0335] Alternative Solution 2: The terminal determines the reported TDW as the actual TDW. In the PUSCH transmission scheduled by the DCI sent after the time T shown in the above equation (2), the new TDW is activated.

[0336] Alternative solution 3: The terminal determines the TDW by setting it to the base station. The base station uses the reported TDW as a time slot for joint channel estimation based on implementation.

[0337] Figure 13 This figure illustrates an example of possible TDW reporting. A terminal (UE) reports its capabilities to a base station (gNB). The base station then sets the configured TDW in the terminal based on the capabilities reported.

[0338] In addition to reporting terminal capabilities, terminals sometimes also report possible TDW. It may be that the value of possible TDW depends on the position of the satellite.

[0339] The base station sets the actual TDW for the terminal based on the report of the possible TDW.

[0340] <Note 2>

[0341] To meet timing accuracy and phase continuity requirements, terminals report TDW as a terminal capability based on the longest updated period of timing precompensation on the satellite orbit. For example, a terminal reports TDW based on the maximum elevation angle with a low timing drift rate on the satellite orbit as a terminal capability. When switching to a different satellite (or satellite orbit), the terminal reports the aforementioned TDW as a terminal capability.

[0342] Alternatively, the terminal may report a timing pre-compensation update rate, a timing drift rate, and / or assistance information about satellite elevation angles, so that the base station can appropriately determine a time slot for joint channel estimation.

[0343] Figure 14 : is a diagram illustrating an example of reporting auxiliary information. Figure 14 As shown, the terminal (UE) reports auxiliary information to the base station (gNB). It can be that the terminal reports auxiliary information when switching to a different satellite (or satellite orbit).

[0344] Alternatively, the terminal may report the auxiliary information when notifying terminal capabilities during initial access, for example.

[0345] <Note 3>

[0346] To meet timing accuracy and phase continuity requirements, the terminal reports TDW as a terminal capability based on the shortest updated period of timing pre-compensation on the satellite orbit. For example, the terminal reports TDW based on the lowest elevation angle with a high timing drift rate on the satellite orbit as the terminal capability. When switching to a different satellite (or satellite orbit), the terminal reports the aforementioned TDW as the terminal capability.

[0347] Alternatively, the terminal reports the timing pre-compensation update rate, the timing drift rate and / or auxiliary information on the satellite elevation angle, so that the base station can appropriately determine the time slot for joint channel estimation.

[0348] <Note 4>

[0349] To meet the timing accuracy and phase continuity requirements, the terminal reports TDW as the terminal capability without considering timing pre-compensation on the satellite orbit. Timing pre-compensation and / or phase adjustment on the satellite orbit are applied at the TDW boundary.

[0350] This means that variations caused by HW such as amplifiers or oscillators are taken into account, but timing pre-compensation and / or phase adjustments in the satellite orbit are not taken into account.

[0351] The base station can recognize that the phase rotation caused by satellite movement has not been compensated in advance by the terminal, and can therefore estimate the phase rotation caused by the timing change caused by satellite movement and make adjustments.

[0352] <Note 5>

[0353] To meet timing accuracy and phase continuity requirements, terminals report TDW as their capabilities without considering on-orbit timing pre-compensation. On-orbit phase pre-compensation is applied continuously regardless of TDW boundaries, and on-orbit timing pre-compensation is applied at TDW boundaries.

[0354] The base station can recognize that the phase rotation caused by satellite motion has not been compensated in advance by the terminal, and can therefore perform joint channel estimation using TDW.

[0355] <Note 6>

[0356] To meet timing accuracy and phase continuity requirements, terminals report TDW as a terminal capability under specific conditions for on-orbit timing precompensation. On-orbit timing precompensation and / or phase adjustment are applied at TDW boundaries.

[0357] The base station can recognize the status of the terminal's TDW function and the fact that the terminal has not pre-compensated for phase rotation caused by satellite motion, and can therefore appropriately determine the time slot for joint channel estimation. The specific conditions envisioned are conditions specified as test conditions for timing pre-compensation requirements.

[0358] <Note 7>

[0359] To meet timing accuracy and phase continuity requirements, terminals report TDW as a terminal capability when specific conditions for on-orbit timing precompensation are met. On-orbit phase precompensation is continuously applied regardless of TDW boundaries, and on-orbit timing precompensation is applied at TDW boundaries.

[0360] The base station can recognize the status of the terminal's TDW function and that the terminal has pre-compensated for phase rotation caused by satellite motion, thereby appropriately determining the time slot for joint channel estimation. The specific conditions envisioned are those specified as test conditions for timing pre-compensation requirements.

[0361] <Note 8>

[0362] Alternatively, whether the terminal continuously applies phase precompensation on the satellite orbit may be indicated to the base station as the terminal capability.

[0363] The timing precompensation rate is more critical than the frequency precompensation rate, but frequency precompensation can also be considered.

[0364] Multiple TDW values ​​(eg, maximum, minimum, average) may also be reported from the terminal.

[0365] The terminal may also indicate which state in the TDW (eg, Supplementary Notes 2 to 7) is reported as the terminal capability.

[0366] The above is the explanation of the notes.

[0367] A terminal of one embodiment of the present disclosure comprises: a receiving circuit for receiving a report indication of a time zone, which is a time zone in which the phase continuity and power consistency of the uplink signal need to be maintained; and a control circuit for determining the periodic reporting of the time zone according to the report indication.

[0368] In one embodiment of the present disclosure, the control circuit determines the time zone according to the position of the moving satellite.

[0369] In one embodiment of the present disclosure, after reporting the time zone, the control circuit maintains the phase continuity and power consistency of the uplink signal in the indicated time zone.

[0370] In one embodiment of the present disclosure, the control circuit determines the time zone to be reported based on the transmission timing of the uplink signal and / or the update period of the frequency control.

[0371] In one embodiment of the present disclosure, the update period depends on the position of the moving satellite.

[0372] In one embodiment of the present disclosure, the control circuit determines the time zone based on at least one of the performance of the terminal, the position of the moving satellite, the phase rotation amount caused by the propagation delay time change performed in the base station, and the phase rotation amount caused by the Doppler frequency change performed in the base station.

[0373] In one embodiment of the present disclosure, the control circuit reports the category used in determining the time zone.

[0374] A base station according to an embodiment of the present disclosure comprises: a transmitting circuit configured to transmit a report indication of a time zone, the time zone being a time zone in which phase continuity and power consistency of an uplink signal need to be maintained; and

[0375] The control circuit performs joint channel estimation based on the periodically received reports of the time zone.

[0376] In a communication method of one embodiment of the present disclosure, the terminal performs the following steps: receiving a report indication of a time zone, which is a time zone where the phase continuity and power consistency of the uplink signal need to be maintained; and determining the periodic reporting of the time zone based on the report indication.

[0377] In a communication method of one embodiment of the present disclosure, the base station performs the following steps: sending a report indication of a time zone, which is a time zone in which the phase continuity and power consistency of the uplink signal need to be maintained; and performing joint channel estimation based on the reports of the time zone periodically received.

[0378] The disclosures of the specification, drawings, and abstract contained in Japanese patent application No. 2023-023753 filed on February 17, 2023 are incorporated herein by reference in their entirety.

[0379] Industrial Applicability

[0380] One aspect of the present disclosure is useful for wireless communication systems.

[0381] Description of Reference Numerals

[0382] 100 Terminal

[0383] 101 Wireless Receiving Unit

[0384] 102 Data reception and processing unit

[0385] 103 Control Department

[0386] 104 Timing / Frequency Adjustment Unit

[0387] 105 Data transmission processing unit

[0388] 106 Wireless Transmission Unit

[0389] 200 base stations

[0390] 201 Wireless Receiving Unit

[0391] 202 Data Receiving and Processing Unit

[0392] 203 Control Department

[0393] 204 Data transmission processing unit

[0394] 205 Wireless Transmission Unit

Claims

1. A terminal comprising: a receiving circuit for receiving a report indication of a time zone, where the time zone is a time zone in which phase continuity and power consistency of an uplink signal need to be maintained; and The control circuit determines the periodic reporting of the time zone according to the reporting instruction.

2. The terminal according to claim 1, wherein: The control circuit determines the time zone based on the position of the moving satellite.

3. The terminal according to claim 1, wherein: After reporting the time zone, the control circuit maintains the phase continuity and power consistency of the uplink signal in the indicated time zone. The terminal according to claim 1 , wherein: The control circuit determines the time zone to be reported according to the transmission timing of the uplink signal and / or the update period of frequency control. The terminal according to claim 4 , wherein: The update period depends on the position of the moving satellite. The terminal according to claim 1 , wherein: The control circuit determines the time zone based on at least one of the performance of the terminal, the position of the moving satellite, the phase rotation amount caused by the propagation delay time variation performed in the base station, and the phase rotation amount caused by the Doppler frequency variation performed in the base station.

7. The terminal according to claim 6, wherein: The control circuit reports the category used in determining the time zone.

8. A base station comprising: a transmitting circuit, transmitting a report indication of a time zone, where the time zone is a time zone in which phase continuity and power consistency of an uplink signal need to be maintained; and The control circuit performs joint channel estimation based on the periodically received reports of the time zone.

9. A communication method comprising the following steps: A report indication of a receiving time zone, where the phase continuity and power consistency of an uplink signal need to be maintained; as well as According to the reporting instruction, the periodic reporting of the time zone is determined.

10. A communication method comprising the following steps: Sending a report indication of a time zone in which phase continuity and power consistency of an uplink signal need to be maintained; as well as Joint channel estimation is performed based on the periodically received reports for the time zone.

Images