Terminal, base station, and communication method

Abstract

This terminal is provided with: a control circuit that determines an orthogonal sequence having a relationship in which, in a frequency domain, at least a portion of an output result obtained by applying the orthogonal sequence to a signal before discrete Fourier transform (DFT) and applying DFT to the signal is mapped to a frequency resource used in a demodulation reference signal; and a transmission circuit that transmits the signal to which the orthogonal sequence is applied.

Description

Terminal, base station and communication method

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

[0002] In recent years, the expansion and diversification of wireless services has led to the expectation of rapid development of the Internet of Things (IoT). Mobile communications are now being used in a wide range of applications, from smartphones and other information terminals to automobiles, homes, home appliances, and industrial equipment. To support this diversification, significant improvements in the performance and functionality of mobile communication systems are required, addressing various requirements, such as increased system capacity, an increased number of connected devices, and low latency. Fifth-generation mobile communication systems (5G) boast high-capacity and ultra-high-speed data transfer (eMBB: enhanced Mobile Broadband), massive machine-type communication (mMTC: massive Machine-Type Communication), and ultra-reliable and low-latency communication (URLLC), providing flexible wireless communications to meet diverse needs.

[0003] The 3rd Generation Partnership Project (3GPP), an international standardization organization, is working on the specification of New Radio (NR) as one of the 5G wireless interfaces.

[0004] 3GPP TS38.104 V15.19.0, “NR Base Station (BS) radio transmission and reception (Release 15),” June 2023.RP-202928, “New WID on NR coverage enhancements,” China Telecom, December 2020.RP-220937, “Revised WID on Further NR coverage enhancements,” China Telecom, March 2022.RP-223534, “Revised WID: NR NTN (Non-Terrestrial Networks) enhancements”, Thales, December 2022.3GPP TS38.211 V18.1.0, “NR Physical channels and modulation (Release 18),” December 2023.3GPP TS38.212 V18.1.0, “NR Multiplexing and channel coding (Release 18),” December 2023.3GPP TS38.213 V18.1.0, “NR Physical layer procedures for control (Release 18),” December 2023.3GPP TS38.214 V18.1.0, “NR Physical layer procedures for data (Release 18),” December 2023.RP-234078, “New WID: Non-Terrestrial Networks (NTN) for NR Phase 3,” Huawei (Moderator, RAN1 Vice-Chair), December 2023.

[0005] However, there is room for further consideration regarding the method of transmitting signals in the uplink.

[0006] Non-limiting examples of the present disclosure contribute to providing a terminal, a base station, and a communication method that can appropriately transmit signals in the uplink.

[0007] A terminal according to one embodiment of the present disclosure includes: a control circuit that determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal; and a transmission circuit that transmits the signal to which the orthogonal sequence has been applied.

[0008] These comprehensive or specific aspects may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0009] According to one embodiment of the present disclosure, signals can be transmitted appropriately in the uplink.

[0010] Further advantages and benefits of one embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features.

[0011] Figure showing an example of DFT spreading Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) using pre Discrete Fourier Transform (DFT) Orthogonal Cover Code (OCC)Block diagram showing an example of the configuration of a portion of a base stationBlock diagram showing an example of the configuration of a portion of a terminalDiagram showing an example of application of pre-DFT OCCDiagram showing an example of application of pre-DFT OCCDiagram showing an example of application of pre-DFT OCCDiagram showing an example of a time domain signal after application of pre-DFT OCCDiagram showing an example of an OCC sequenceDiagram showing an example of an OCC sequenceDiagram showing an example of an OCC sequenceFlowchart showing an example of operation of a terminalDiagram showing an example of application of pre-DFT OCCDiagram showing an example of application of pre-DFT OCCDiagram showing an example of an OCC sequenceFlowchart showing an example of operation of a terminalDownlink Control Information (DCI) bit field and Demodulation Reference 3. A diagram showing an example of the relationship between a DCI bit field, a DMRS port, and an OCC sequence number. 4. A diagram showing an example of the relationship between a DCI bit field, a DMRS port, and an OCC sequence number. 5. A diagram showing an example of the relationship between a DCI bit field, a DMRS port, and an OCC sequence number. 6. A flowchart showing an example of the operation of a terminal. 7. A block diagram showing an example of the configuration of a base station. 8. A block diagram showing an example of the configuration of a terminal. 9. A diagram of an example architecture of a 3GPP NR system. 10. A diagram of an example functional division in 5G O-RAN.

[0012] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0013] The basic functions of eMBB or URLLC were specified in Release 15, and from Release 16 onwards, URLLC has been extended to include Industrial IoT, Vehicle-to-Everything (V2X), and Non-Terrestrial Networks (NTNs) including satellites. 3GPP's extended specifications have been called "5G-Advanced" since Release 18.

[0014] In NR, for example, in addition to frequency bands below 6 GHz, such as the 700 MHz to 3.5 GHz band (also referred to as Frequency Range 1 (FR1)), which have been used for cellular communications, millimeter wave bands such as the 28 GHz or 39 GHz band (also referred to as Frequency Range 2 (FR2)), which can ensure wide bandwidth, can be utilized (see, for example, Non-Patent Document 1). Furthermore, for example, in FR1, there is a possibility that a frequency band such as the 3.5 GHz band, which is higher than the frequency bands used in Long Term Evolution (LTE) or 3G (3rd Generation mobile communication systems), will be used.

[0015] The higher the frequency band, the greater the radio wave propagation loss and the more likely it is that radio wave reception quality will deteriorate. Therefore, when NR uses a frequency band higher than that of LTE or 3G, for example, it is expected to ensure a communication area (or coverage) comparable to that of radio access technologies (RATs) such as LTE or 3G, in other words, to ensure appropriate communication quality. For example, in 3GPP Release 17 (e.g., referred to as "Rel. 17") and Release 18 (e.g., referred to as "Rel. 18"), methods for improving coverage in NR have been studied (see, for example, Non-Patent Document 2 and Non-Patent Document 3).

[0016] Furthermore, coverage plays a key role in supporting Terrestrial Networks (TNs), which have significantly longer communication distances than existing Terrestrial Networks (TNs). NR Rel. 15 is specified as a radio access technology for terrestrial networks. Meanwhile, Release 17 (Rel. 17) supports non-terrestrial networks (NTNs), such as communications using satellites or high-altitude platform stations (HAPSs). In Release 18 (Rel. 18), NTN extension technologies have been studied, and improvements to NTN uplink coverage have been considered (see, for example, Non-Patent Document 4).

[0017] In NR, a terminal (e.g., also referred to as user equipment (UE)) transmits and receives data in accordance with, for example, a layer 1 control signal (e.g., Downlink Control Information (DCI)) on a downlink control channel (e.g., Physical Downlink Control Channel (PDCCH)) from a base station (e.g., also referred to as gNB) or resource allocation indicated by Radio Resource Control (RRC) in layer 3 (see, for example, Non-Patent Documents 5 to 8).

[0018] In NR, repetition transmission (repetition) can be applied as one of the uplink (UL) coverage extension techniques (see, for example, Non-Patent Document 7 or 8). In NR up to Release 18, channels to which repetition can be applied are uplink data channels (e.g., PUSCH: Physical Uplink Shared Channel) scheduled by DCI format 0-1 or DCI format 0-2 (e.g., PUSCH scheduled after parameters are configured by a pusch-Config information element (IE), which is a terminal-specific RRC), Msg. 3 PUSCH (e.g., PUSCH scheduled by a Random Access Response (RAR)), uplink control channels (e.g., PUCCH: Physical Uplink Control Channel), and random access channels (e.g., PRACH: Physical Random Access Channel).

[0019] In coverage-limited scenarios, such as NTNs using handheld terminals, repetition may be applied to uplink transmissions due to large propagation losses. However, repetition increases the time and frequency resources used for communication in proportion to the number of repetitions, which may result in a decrease in communication capacity.

[0020] Therefore, as another method for improving coverage, studies have been conducted to improve the communication capacity and transmission rate of uplink communication by applying spreading using an orthogonal sequence (e.g., Orthogonal Cover Code (OCC)) to the PUSCH (see, for example, Non-Patent Document 9). For example, OCC may be OCC applied between Orthogonal Frequency Domain Multiplexing (OFDM) symbols, OCC applied between slots, or OCC applied within an OFDM symbol.

[0021] One method for implementing OCC within an OFDM symbol is, as shown in FIG. 1 , a method in which OCC is applied to modulated data symbols before DFT (hereinafter also referred to as "pre-DFT OCC") in Discrete Fourier Transform spreading OFDM (DFT-s-OFDM) and then DFT precoding (or spreading, transform precoding) is performed. In this method, repetitions of a spreading factor (SF) (or OCC sequence length) are applied to the data symbols (sequences) before DFT precoding, and the repetitions are multiplied by the OCC. This method has been introduced as PUCCH format 4 in existing NR (see, for example, Non-Patent Document 5). PUCCH format 4 supports OCC sequence lengths of 2 or 4 (spreading factors of 2 or 4, multiplexing capacity for 2 or 4 terminals). Furthermore, PUCCH format 4 supports only one resource block (RB) for resource allocation. In addition, in PUCCH format 4, the OCC sequence to be used is provided by PUCCH resource allocation.

[0022] However, there is room for further study on the transmission and control schemes for PUSCH with pre-DFT OCC.

[0023] For example, a pre-DFT OCC using a cyclic shift code as an OCC sequence is applied, and the frequency domain signal (output result) after applying DFT precoding has a comb structure. Furthermore, PUSCH using DFT-s-OFDM supports Demodulation Reference Signal (DMRS) Configuration Type 1. DMRS Configuration Type 1 has a comb structure in the frequency domain (e.g., DMRS mapping in the frequency domain).

[0024] Depending on the applied OCC sequence (e.g., OCC sequence number), it is determined which comb number (e.g., subcarrier or resource element (RE)) in the frequency domain comb structure to which resources are allocated. Therefore, if the use of the pre-DFT OCC is controlled independently of the comb structure of the DMRS in the frequency domain, for example, the frequency resources (e.g., subcarriers or RE) to which the PUSCH is mapped as a result of the pre-DFT OCC and DFT may not coincide with the frequency resources (e.g., subcarriers or RE) to which the DMRS is mapped, which may result in degradation of channel estimation performance. Therefore, when using the pre-DFT OCC, it is expected that the relationship with the mapping position (e.g., comb structure) of the DMRS in the frequency domain should be taken into consideration.

[0025] Furthermore, when using pre-DFT OCC, it is expected that it will be as flexible as possible and support the maximum multiplexing capacity. Here, the maximum number of ports (e.g., the number of multiplexings) supported in the existing DMRS Configuration Type 1 is 4 for single-symbol DMRS and 8 for double-symbol DMRS. Assuming that the multiplexing capacity of the OCC does not exceed the multiplexing capacity of the DMRS, for example, in the case of DMRS Configuration Type 1, it is expected that an OCC sequence length (or spreading factor, multiplexing capacity) of at least 8 will be supported in order to support as much flexible and large a multiplexing capacity as possible. However, when resource allocation is limited to 1 RB, as in PUCCH format 4, it is difficult to support a pre-DFT OCC with an OCC sequence length of 8 (spreading factor 8, multiplexing capacity 8) even when the maximum multiplexing capacity of the DMRS is 8.

[0026] Regarding the method of signaling the OCC sequence, for example, in the case of a PUSCH that transmits data according to resource allocation indicated by DCI, dynamic signaling of the OCC sequence is possible by adding a bit field for signaling the OCC sequence to the DCI, but this increases DCI overhead.In scenarios where coverage improvement is expected, it is expected that the DCI overhead will be small.

[0027] In one non-limiting embodiment of the present disclosure, a method for improving the transmission quality and transmission capacity of a PUSCH using a pre-DFT OCC, or a method for reducing the overhead of reporting a pre-DFT OCC sequence, will be described.

[0028] Non-limiting embodiments of the present disclosure will be described below.

[0029] [Overview of Communication System] A communication system according to each embodiment of the present disclosure includes, for example, at least one base station and at least one terminal.

[0030] FIG. 2 is a block diagram showing a configuration example of a portion of a base station 100 according to an embodiment of the present disclosure, and FIG. 3 is a block diagram showing a configuration example of a portion of a terminal 200 according to an embodiment of the present disclosure.

[0031] In the base station 100 shown in Fig. 2, a control unit (e.g., corresponding to a control circuit) determines an orthogonal sequence having a relationship such that at least a part of a frequency domain output result obtained by applying an orthogonal sequence (pre-DFT OCC) to a pre-DFT signal and applying a DFT to the signal is mapped to a frequency resource used for a demodulation reference signal (DMRS). A communication unit (e.g., corresponding to a receiving circuit) receives a signal (e.g., a PUSCH) to which the orthogonal sequence is applied.

[0032] In terminal 200 shown in Fig. 3, a control unit (e.g., corresponding to a control circuit) determines an orthogonal sequence having a relationship in which at least a part of a frequency domain output result obtained by applying an orthogonal sequence (pre-DFT OCC) to a pre-DFT signal and applying a DFT to the signal is mapped to a frequency resource used for a demodulation reference signal (DMRS). A communication unit (e.g., corresponding to a transmission circuit) transmits a signal (e.g., a PUSCH) to which the orthogonal sequence is applied.

[0033] (First Embodiment) In this embodiment, pre-DFT OCC is applied to PUSCH using DFT-s-OFDM.

[0034] In this embodiment, base station 100 and terminal 200 apply (or determine or set) a pre-DFT OCC sequence having a relationship in which at least a portion of the frequency domain output result obtained by applying pre-DFT OCC (OCC to the signal before DFT) and applying DFT to the signal (for example, referred to as "pre-DFT OCC and post-DFT application") is mapped to the frequency resources used for DMRS.

[0035] For example, when applying a pre-DFT OCC, an OCC may be applied (or set or determined) that has a relationship between the OCC sequence number and the DMRS port such that "the output result (e.g., comb number, subcarrier or RE to which the data signal is mapped) given by the pre-DFT OCC and the comb structure in the frequency domain after applying the DFT is mapped to the subcarrier (or RE) used for the DMRS."

[0036] For example, it is assumed that PUSCH using DFT-s-OFDM with pre-DFT OCC and DMRS configuration Type 1 are used.

[0037] DMRS Configuration Type 1 has a comb structure in the frequency domain in which DMRS sequences of DMRS ports #0, #1, #4, and #5 are mapped to RE numbers #0, #2, #4, #6, #8, and #10 within an RB (e.g., RE numbers #0 to #11). DMRS Configuration Type 1 also has a comb structure in the frequency domain in which DMRS sequences of DMRS ports #2, #3, #6, and #7 are mapped to RE numbers #1, #3, #5, #7, #9, and #11 within an RB.

[0038] FIG. 4 shows an example in which a pre-DFT OCC with an OCC sequence length of 2 (spreading factor 2) is applied.

[0039] For example, as shown in FIG. 4 , when a pre-DFT OCC with an OCC sequence length of 2 (spreading factor 2) is applied, the output result provided by the pre-DFT OCC and the frequency domain comb structure after application of the DFT may be RE numbers #0, #2, #4, #6, #8, and #10 within an RB (e.g., RE numbers #0 to #11) when OCC sequence number #0 is applied, and may be RE numbers #1, #3, #5, #7, #9, and #11 within an RB when OCC sequence number #1 is applied.

[0040] Therefore, when a pre-DFT OCC with an OCC sequence length of 2 (spreading factor 2) is applied, as shown in Fig. 4, OCC sequence number #0, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after application of the DFT can be REs #0, #2, #4, #6, #8, and #10, is mapped to the REs used for DMRS ports #0, #1, #4, and #5, and can therefore be used in conjunction with DMRS ports #0, #1, #4, and #5. Also, as shown in Fig. 4, OCC sequence number #1, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after application of the DFT can be REs #1, #3, #5, #7, #9, and #11, is mapped to the REs used for DMRS ports #2, #3, #6, and #7, and can therefore be used in conjunction with DMRS ports #2, #3, #6, and #7.

[0041] FIG. 5 shows an example in which a pre-DFT OCC with an OCC sequence length of 4 (spreading factor 4) is applied.

[0042] For example, as shown in FIG. 5 , when a pre-DFT OCC with an OCC sequence length of 4 (spreading factor 4) is applied, the output result provided by the pre-DFT OCC and the frequency domain comb structure after application of the DFT may be RE numbers #0, #4, and #8 within an RB (e.g., RE numbers #0 to #11) when OCC sequence number #0 is applied, RE numbers #1, #5, and #9 within an RB when OCC sequence number #1 is applied, RE numbers #2, #6, and #10 within an RB when OCC sequence number #2 is applied, and RE numbers #3, #7, and #11 within an RB when OCC sequence number #3 is applied.

[0043] Therefore, when a pre-DFT OCC with an OCC sequence length of 4 (spreading factor 4) is applied, as shown in Fig. 5 , OCC sequence number #0, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after DFT application can be REs #0, #4, and #8, is mapped to the RE used for DMRS port #0, #1, #4, or #5, and can therefore be used in conjunction with DMRS port #0, #1, #4, or #5. Also, as shown in Fig. 5 , OCC sequence number #1, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after DFT application can be REs #1, #5, and #9, is mapped to the RE used for DMRS port #2, #3, #6, or #7, and can therefore be used in conjunction with DMRS port #2, #3, #6, or #7. 5, OCC sequence number #2, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after DFT application can be REs #2, #6, and #10, is mapped to the REs used for DMRS ports #0, #1, #4, and #5, and can therefore be used in conjunction with DMRS ports #0, #1, #4, and #5. Also, as shown in FIG. 5, OCC sequence number #3, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after DFT application can be REs #3, #7, and #11, is mapped to the REs used for DMRS ports #2, #3, #6, and #7, and can therefore be used in conjunction with DMRS ports #2, #3, #6, and #7.

[0044] FIG. 6 shows an example in which a pre-DFT OCC with an OCC sequence length of 6 (spreading factor 6) is applied.

[0045] For example, as shown in FIG. 6 , when a pre-DFT OCC with an OCC sequence length of 6 (spreading factor 6) is applied, the output result provided by the pre-DFT OCC and the frequency domain comb structure after application of the DFT may be RE numbers #0 and #6 in an RB (e.g., RE numbers #0 to #11) when OCC sequence number #0 is applied, RE numbers #1 and #7 in the RB when OCC sequence number #1 is applied, RE numbers #2 and #8 in the RB when OCC sequence number #2 is applied, RE numbers #3 and #9 in the RB when OCC sequence number #3 is applied, RE numbers #4 and #10 in the RB when OCC sequence number #4 is applied, and RE numbers #5 and #11 in the RB when OCC sequence number #5 is applied.

[0046] Therefore, when a pre-DFT OCC with an OCC sequence length of 6 (spreading factor 6) is applied, as shown in Fig. 6, OCC sequence number #0, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after DFT application can be REs #0 and #6, is mapped to the REs used for DMRS ports #0, #1, #4, or #5, and can therefore be used in conjunction with DMRS ports #0, #1, #4, or #5. Also, as shown in Fig. 6, OCC sequence number #1, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after DFT application can be REs #1 and #7, is mapped to the REs used for DMRS ports #2, #3, #6, or #7, and can therefore be used in conjunction with DMRS ports #2, #3, #6, or #7. 6 , OCC sequence number #2, whose output results provided by the pre-DFT OCC and the comb-like structure in the frequency domain after application of the DFT can be REs #2 and #8, is mapped to the RE used for DMRS port #0, #1, #4, or #5, and can therefore be used in conjunction with DMRS port #0, #1, #4, or #5. Also, as shown in FIG. 6 , OCC sequence number #3, whose output results provided by the pre-DFT OCC and the comb-like structure in the frequency domain after application of the DFT can be REs #3 and #9, is mapped to the RE used for DMRS port #2, #3, #6, or #7, and can therefore be used in conjunction with DMRS port #2, #3, #6, or #7. 6 , OCC sequence number #4, whose output results provided by the pre-DFT OCC and the comb-like frequency domain structure after DFT application can be REs #4 and #10, is mapped to the RE used for DMRS port #0, #1, #4, or #5, and can therefore be used in conjunction with DMRS port #0, #1, #4, or #5. Also, as shown in FIG. 6 , OCC sequence number #5, whose output results provided by the pre-DFT OCC and the comb-like frequency domain structure after DFT application can be REs #5 and #11, is mapped to the RE used for DMRS port #2, #3, #6, or #7, and can therefore be used in conjunction with DMRS port #2, #3, #6, or #7.

[0047] As described above, according to the present embodiment, output results (e.g., comb numbers, subcarriers or REs to which data signals are mapped) given by the frequency domain comb structure after applying the pre-DFT OCC and DFT are mapped to subcarriers (or REs) used for the DMRS. This allows the transmitting side (e.g., terminal 200) to transmit a data signal (e.g., PUSCH) and a DMRS using the same subcarriers or REs, thereby improving the accuracy of channel estimation at the receiving side (e.g., base station 100).

[0048] Note that the time domain signal y after applying pre-DFT OCC before applying DFT may be given by, for example, the following equation (1).

[0049] where d(0), ..., d(M symb layer -1) is the modulation symbol sequence. M SC PUSCH =M RB PUSCH ・N SC RB and M RB PUSCH is the number of allocated RBs, and N SC RB is the number of subcarriers (or REs) per RB. symb layer is the number of modulation symbols per layer, and N SF is the sequence length or spreading factor of the pre-DFT OCC. n (k) is the OCC sequence of pre-DFT OCC sequence number n.

[0050] Figure 7 shows M RB PUSCH =1, N SC RB = 12 and N SF 1 shows an example of a time domain signal y(t) after applying pre-DFT OCC at M = 4. The pre-DFT OCC can be applied to every OFDM symbol. The number of data modulation symbols transmitted in one OFDM symbol is M SC PUSCH / N SF =MRB PUSCH ・N SC RB / N SF Therefore, the modulation symbol sequence is M SC PUSCH / N SF Each OFDM symbol is divided into M SC PUSCH / N SF The pre-DFT OCC is applied to a data symbol sequence including d(0), d(1), and d(2), and a set of d(3), d(4), and d(5) in the example of FIG. 7 .

[0051] Furthermore, the frequency domain signal z after applying the pre-DFT OCC and DFT may be given by, for example, the following equation (2).

[0052] Furthermore, cyclic shift sequences are generally known as OCC sequences that result in a comb structure for the frequency domain signal after DFT precoding using pre-DFT OCC. As examples of pre-DFT OCC sequences, Fig. 8 shows an OCC sequence with an OCC sequence length of 2 (spreading factor 2), Fig. 9 shows an OCC sequence with an OCC sequence length of 4 (spreading factor 4), and Fig. 10 shows an OCC sequence with an OCC sequence length of 6 (spreading factor 6).

[0053] In this embodiment, the OCC sequence number used for the pre-DFT OCC may be controlled (e.g., determined or set) or limited depending on the subcarrier (or RE) or DMRS port used for the DMRS.

[0054] For example, when DMRS port #0, #1, #4, or #5 is used, base station 100 and terminal 200 may set OCC sequence number #0 in the example of Figure 4 (when OCC sequence length is 2), set OCC sequence number #0 or #2 in the example of Figure 5 (when OCC sequence length is 4), and set OCC sequence number #0, #2, or #4 in the example of Figure 6 (when OCC sequence length is 6). Furthermore, when DMRS port #2, #3, #6, or #7 is used, base station 100 and terminal 200 may set OCC sequence number #1 in the example of Figure 4 (when OCC sequence length is 2), set OCC sequence number #1 or #3 in the example of Figure 5 (when OCC sequence length is 4), and set OCC sequence number #1, #3, or #5 in the example of Figure 6 (when OCC sequence length is 6).

[0055] [Example of Operation of Terminal 200] FIG. 11 is a flowchart showing an example of operation of determining an OCC sequence in terminal 200.

[0056] In FIG. 11, terminal 200 acquires at least one of information on DMRS configuration and information on DMRS ports (S101).

[0057] Terminal 200 acquires information (for example, sequence length or spreading factor) related to the OCC sequence (pre-DFT OCC sequence) (S102).

[0058] Terminal 200 determines an applicable or to-be-applied OCC sequence based on the acquired DMRS configuration and information on the DMRS port (S103). For example, as described above, terminal 200 may determine an OCC having a relationship in which subcarriers or REs given in the comb structure in the frequency domain after DFT application and pre-DFT OCCs are mapped to subcarriers or REs used for DMRS.

[0059] As described above, in this embodiment, terminal 200 takes into consideration the relationship with the mapping position (e.g., comb structure) of the DMRS in the frequency domain when using the pre-DFT OCC. In this way, by controlling the use of the pre-DFT OCC based on the comb structure in the frequency domain of the DMRS, the frequency resources (e.g., subcarriers or REs) to which the PUSCH is mapped as an output result of applying the pre-DFT OCC and DFT match the frequency resources (e.g., subcarriers or REs) to which the DMRS is mapped, thereby improving channel estimation performance.

[0060] Therefore, according to the present embodiment, it is possible to improve the transmission quality of the PUSCH using pre-DFT OCC. As a result, terminal 200 can appropriately transmit signals in the uplink.

[0061] (First Variation of First Embodiment) The output result (e.g., comb number, subcarrier or RE to which the data signal is mapped) given by the frequency domain comb structure after applying pre-DFT OCC and DFT may not match the subcarrier or RE to which the DMRS is mapped.

[0062] In this variant, an OCC may be applied that has the relationship that "the output results (e.g., comb numbers, subcarriers or REs to which data signals are mapped) given by the pre-DFT OCC and the frequency domain comb structure after applying the DFT are mapped to the subcarriers (REs) that are as similar as possible to the subcarriers (or REs) used for DMRS."

[0063] For example, as shown in FIG. 12 , when a pre-DFT OCC with an OCC sequence length of 3 (spreading factor 3) is applied, the output result provided by the pre-DFT OCC and the frequency domain comb structure after application of the DFT may be RE numbers #0, #3, #6, and #9 in an RB (e.g., RE numbers #0 to #11) when OCC sequence number #0 is applied, RE numbers #1, #4, #7, and #10 in an RB when OCC sequence number #1 is applied, and RE numbers #2, #5, #8, and #11 in an RB when OCC sequence number #2 is applied.

[0064] 12 , when a pre-DFT OCC with an OCC sequence length of 3 (spreading factor 3) is applied, OCC sequence number #0, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after application of DFT can be REs #0, #3, #6, and #9, is mapped to, for example, some of the REs (REs #0 and #6) used for DMRS port #0, #1, #4, or #5, and can therefore be used in conjunction with DMRS port #0, #1, #4, or #5. Also, OCC sequence number #1, whose output results provided by the pre-DFT OCC and the frequency-domain comb structure after application of DFT can be REs #1, #4, #7, and #10, is mapped to, for example, some of the REs (REs #1 and RE #7) used for DMRS port #2, #3, #6, or #7, and can therefore be used in conjunction with DMRS port #2, #3, #6, or #7. Furthermore, OCC sequence number #2, whose output results given by the comb structure in the frequency domain after applying the pre-DFT OCC and DFT can be REs 2, 5, 8, and 11, is mapped to, for example, some of the REs (REs 2 and 8) used for DMRS ports 0, 1, 4, or 5, and can therefore be used in conjunction with DMRS ports 0, 1, 4, or 5.

[0065] As shown in Figure 12, although not all subcarriers (REs) in the frequency domain comb structure after applying pre-DFT OCC and DFT are the same as the subcarriers (REs) to which DMRSs are mapped, two out of four subcarriers are mapped to the same subcarriers (REs) as DMRSs.

[0066] This makes it possible to minimize the deterioration of channel estimation accuracy.

[0067] (Variation 2 of Embodiment 1) As in Variation 1 of Embodiment 1, depending on the OCC sequence length (spreading factor), the output result (e.g., comb number, subcarrier or RE to which data signal is mapped) given by the pre-DFT OCC and the frequency domain comb structure after applying DFT may not match the RE mapping of DMRS.

[0068] In this modification, an OCC sequence may be used in which the subcarrier (RE) spacing in the pre-DFT OCC and the frequency domain comb structure after DFT application is an integer multiple of the subcarrier (RE) spacing in the DMRS mapping. On the other hand, an OCC sequence in which the subcarrier (RE) spacing in the pre-DFT OCC and the frequency domain comb structure after DFT application is not an integer multiple of the subcarrier (RE) spacing in the DMRS mapping may not be used.

[0069] For example, the subcarrier (RE) spacing in the RE mapping of DMRS in DMRS Configuration Type 1 is 2. Here, a subcarrier (RE) spacing of 2 means that a DMRS sequence is mapped to RE numbers #0, #2, #4, #6, #8, and #10 within an RB, or RE numbers #1, #3, #5, #7, #9, and #11 within an RB, forming a comb structure in the frequency domain.

[0070] The subcarrier (RE) spacing in the frequency domain comb structure after applying the pre-DFT OCC and DFT is equivalent to the OCC sequence length (spreading factor). Therefore, for example, for DMRS Configuration Type 1, a pre-DFT OCC (e.g., OCC sequence lengths of 2, 4, and 6) with an OCC sequence length (spreading factor) that is an integer multiple of the subcarrier (RE) spacing of 2 may be applied.

[0071] Note that a pre-DFT OCC with an OCC sequence length (spreading factor) of 8 may be applied in combination with a second embodiment described later.

[0072] According to this modification, the output results (e.g., comb numbers, subcarriers or REs to which data signals are mapped) given by the pre-DFT OCC and the frequency domain comb structure after applying DFT can be mapped to the same subcarriers (REs) as the DMRS.

[0073] (Embodiment 2) For example, when pre-DFT OCC is applied and the granularity (or allocation unit) of frequency domain resource allocation is 1 RB (e.g., 12 subcarriers), the OCC sequence length (spreading factor) that can be supported to match the pre-DFT OCC and the frequency domain comb structure after DFT application with DMRS Configuration Type 1 is an OCC sequence length that is a multiple of 2 and a divisor of 12. For example, for DMRS Configuration Type 1, the OCC sequence lengths that satisfy the above condition are 2, 4, 6, or 12.

[0074] On the other hand, to support multiplexing of multiple terminals on the same time and frequency resources using pre-DFT OCC, it is desirable to consider not only data multiplexing using pre-DFT OCC but also DMRS multiplexing, and to consider a multiplexing number that is equal to or less than the number of DMRS multiplexed ports. For example, the maximum number of multiplexed ports in DMRS Configuration Type 1 is 8.

[0075] Therefore, in order to support as much flexible and large multiplexing capacity as possible in a given DMRS configuration, for example, DMRS configuration Type 1 is expected to support at least an OCC sequence length (spreading factor) of 8 in addition to OCC sequence lengths of 2, 4, and 6. However, as mentioned above, when the granularity of frequency domain resource allocation is 1 RB (e.g., 12 subcarriers), it is difficult to support an OCC sequence length of 8 because this condition is not met.

[0076] In NTN, it is assumed that the satellite and terminal are mainly in a line-of-sight environment. In this case, direct waves are dominant, resulting in a propagation environment with little frequency selectivity, and fluctuations in the frequency direction are small. Therefore, the loss of OCC orthogonality due to frequency-selective fading is small. Furthermore, it is thought that the loss of orthogonality is small even when OCC spreading is performed across multiple RBs.

[0077] Therefore, in this embodiment, when applying pre-DFT OCC to PUSCH, base station 100 and terminal 200 control the allocation unit (or granularity) of frequency resources (e.g., RBs) according to the length (or spreading factor) of the OCC sequence, and transmit or receive PUSCH using frequency resources allocated based on the allocation unit.

[0078] For example, when applying pre-DFT OCC, frequency domain resource allocation is set in units of "N" RBs (units of N RBs) according to the OCC sequence length (spreading factor), where N is the smallest integer such that the OCC sequence length is a multiple of 2 and a divisor of (12 × N) for DMRS Configuration Type 1, for example.

[0079] For example, when the OCC sequence lengths are 2, 4, and 6, N=1, and OCC sequence lengths 2, 4, and 6 are multiples of 2 and divisors of (12×N)=12, satisfying the above condition. Also, when the OCC sequence length is 8, N=2, and OCC sequence length 8 is a multiple of 2 and a divisor of (12×N)=24, satisfying the above condition.

[0080] In this embodiment, for example, as in the first embodiment, an OCC sequence may be applied that has the relationship that "the output results (e.g., comb numbers, subcarriers or REs to which data signals are mapped) given by the pre-DFT OCC and the comb structure in the frequency domain after applying the DFT are mapped to the subcarriers (or REs) used for the DMRS."

[0081] FIG. 13 shows an example in which a pre-DFT OCC with an OCC sequence length of 8 (spreading factor 8) is applied.

[0082] For example, as shown in FIG. 13 , when a pre-DFT OCC with an OCC sequence length of 8 (spreading factor 8) is applied, the output results provided by the frequency domain comb structure after applying the pre-DFT OCC and DFT are RE numbers #0 and #8 in the even RBs (e.g., REs #0 to #11) and RE #4 in the odd RBs (e.g., REs #0 to #11) in units of 2 RBs when OCC sequence number #0 is applied; RE numbers #1 and #9 in the even RBs and #5 in the odd RBs in units of 2 RBs when OCC sequence number #1 is applied; RE numbers #2 and #10 in the even RBs and #6 in the odd RBs in units of 2 RBs when OCC sequence number #2 is applied; and RE numbers #2 and #10 in the even RBs and #6 in the odd RBs in units of 2 RBs when OCC sequence number #3 is applied. The RE numbers will be #3, #11, and #7 in odd RBs; when OCC sequence number #4 is applied, the RE numbers will be #4 in even RBs and #0, #8 in odd RBs in units of 2 RBs; when OCC sequence number #5 is applied, the RE numbers will be #5 in even RBs and #1, #9 in odd RBs in units of 2 RBs; when OCC sequence number #6 is applied, the RE numbers will be #6 in even RBs and #2, #10 in odd RBs in units of 2 RBs; and when OCC sequence number #7 is applied, the RE numbers will be #7 in even RBs and #3, #11 in odd RBs in units of 2 RBs.

[0083] 13 , when a pre-DFT OCC with an OCC sequence length of 8 (spreading factor 8) is applied, OCC sequence number #0, which results in an output result provided by the pre-DFT OCC and the comb-shaped frequency domain structure after application of the DFT, and which can correspond to RE numbers #0 and #8 in even RBs and RE #4 in odd RBs in units of 2 RBs, can be used in conjunction with DMRS ports #0, #1, #4, or #5. Also, OCC sequence number #1, which results in an output result provided by the pre-DFT OCC and the comb-shaped frequency domain structure after application of the DFT, and which can correspond to RE numbers #1 and #9 in even RBs and RE #5 in odd RBs in units of 2 RBs, can be used in conjunction with DMRS ports #1, #2, #6, or #7. Furthermore, OCC sequence number #2, whose output result provided by the frequency domain comb structure after application of the pre-DFT OCC and DFT can be RE numbers #2 and #10 in even RBs and RE #6 in odd RBs in 2-RB units, can be used with DMRS ports #0, #1, #4, or #5. Furthermore, OCC sequence number #3, whose output result provided by the frequency domain comb structure after application of the pre-DFT OCC and DFT can be RE numbers #3 and #11 in even RBs and RE #7 in odd RBs in 2-RB units, can be used with DMRS ports #2, #3, #6, or #7. Furthermore, OCC sequence number #4, whose output result provided by the frequency domain comb structure after application of the pre-DFT OCC and DFT can be RE number #4 in even RBs and RE #0 and #8 in odd RBs in 2-RB units, can be used with DMRS ports #0, #1, #4, or #5. Furthermore, OCC sequence number #5, whose output result provided by the comb structure in the frequency domain after applying the pre-DFT OCC and DFT can be RE number #5 in even RBs and REs #1 and #9 in odd RBs in 2-RB units, can be used in conjunction with DMRS ports #2, #3, #6, or #7. Furthermore, OCC sequence number #6, whose output result provided by the comb structure in the frequency domain after applying the pre-DFT OCC and DFT can be RE number #6 in even RBs and REs #2 and #10 in odd RBs in 2-RB units, can be used in conjunction with DMRS ports #0, #1, #4, or #5.Furthermore, OCC sequence number #7, which can be RE number #7 in even RBs and REs #3 and #11 in odd RBs in units of 2 RBs as an output result provided by the comb structure in the frequency domain after applying the pre-DFT OCC and DFT, can be used in conjunction with DMRS port #2, #3, #6, or #7.

[0084] For example, a pre-DFT OCC sequence with an OCC sequence length of 8 (spreading factor 8) may be given by the sequence shown in FIG.

[0085] [Example of Operation of Terminal 200] FIG. 15 is a flowchart showing an example of operation of terminal 200.

[0086] In FIG. 15, terminal 200 acquires information (for example, sequence length or spreading factor) related to an OCC sequence (pre-DFT OCC sequence) (S201).

[0087] Terminal 200 determines frequency domain allocation resources (e.g., granularity such as the value of N) according to the OCC sequence length based on the acquired information about the OCC sequence (S202). For example, for DMRS Configuration Type 1, terminal 200 determines frequency domain allocation resources based on the value of N, which is the smallest integer such that the OCC sequence length is a multiple of 2 and a divisor of (12 × N).

[0088] In this way, by setting (or changing) the granularity of frequency domain resource allocation (allocation unit) according to the OCC sequence length (spreading factor) of the pre-DFT OCC, it is possible to match the comb structure of the pre-DFT OCC and the frequency domain after DFT application with that of DMRS Configuration Type 1 according to the OCC sequence length. For example, even for DMRS Configuration Type 1 (maximum number of multiplexed ports: 8), it is possible to support an OCC sequence length of 8 by setting the granularity of frequency domain resource allocation to 2 RBs. Thus, according to this embodiment, it is possible to support the maximum multiplexing capacity as flexibly as possible when using the pre-DFT OCC, thereby improving the transmission capacity of the PUSCH using the pre-DFT OCC.

[0089] Note that, in the present embodiment, as in the first embodiment, an example has been described in which an OCC sequence having the relationship that "output results (e.g., comb numbers, subcarriers or REs to which data signals are mapped) provided by a pre-DFT OCC and a comb structure in the frequency domain after application of DFT are mapped to subcarriers (or REs) used for DMRS" is applied, but the present embodiment is not limited to this, and other methods for applying the pre-DFT OCC sequence (methods for applying an OCC sequence that do not have the above relationship) may also be used.

[0090] Furthermore, in the above embodiment, the value of N used in the RB allocation unit (N RB units) has been described as the smallest integer for which the OCC sequence length is a multiple of 2 and a divisor of (12 × N) for DMRS Configuration Type 1, but this is not limiting. For example, a parameter related to the multiple of the OCC sequence length ("2" in the above example) and a parameter related to the divisor ("12" in the above example) may be set according to the DMRS configuration or the number of REs (or the number of subcarriers) constituting an RB.

[0091] (Variation of Embodiment 2) Note that the control of the granularity of frequency domain resource allocation (allocation in units of N RBs) according to the OCC sequence length (spreading factor) in this embodiment is not limited to PUSCH according to DFT-s-OFDM to which pre-DFT OCC is applied. For example, the control of the granularity of frequency domain resource allocation according to the OCC sequence length (spreading factor) in this embodiment can also be applied to PUSCH according to CP-OFDM to which frequency domain OCC (FD-OCC) is applied.

[0092] (Embodiment 3) In NR, the DMRS port of a PUSCH (Dynamic Grant-PUSCH: DG-PUSCH) that is dynamically scheduled by DCI format 0-1 or DCI format 0-2 is determined based on information in the Antenna port field of the DCI.

[0093] As in the above-described embodiment, the output results (e.g., comb numbers, subcarriers or REs to which data signals are mapped) provided by the pre-DFT OCC and the frequency domain comb structure after DFT application are associated with the subcarriers (or REs) used for DMRS, which is expected to improve the channel estimation accuracy of the PUSCH to which the pre-DFT OCC is applied.

[0094] Therefore, in the present embodiment, when applying a pre-DFT OCC to a PUSCH, base station 100 and terminal 200 determine a sequence of the pre-DFT OCC (e.g., an OCC sequence number) based on the value of a field (e.g., an Antenna port field) that indicates a DMRS port included in DCI or the DMRS port indicated by the Antenna port field, and transmit or receive a PUSCH to which the determined OCC sequence is applied. That is, the sequence of the pre-DFT OCC (OCC sequence number) is implicitly indicated to terminal 200 by the Antenna port field included in DCI.

[0095] For example, in a PUSCH using DFT-s-OFDM, when dmrs-Type = 1 (e.g., DMRS configuration Type 1 is applied) and maxLength = 1 (e.g., single-symbol DMRS is applied), the relationship between the value of the DCI bit field and the DMRS port is as shown in FIG. 16 .

[0096] In this embodiment, in addition to the relationship between the DCI bit field and the DMRS port shown in FIG. 16, the DMRS port (or the value of the DCI bit field) is associated with the OCC sequence number as shown in FIG. 17. As a result, terminal 200 determines the pre-DFT OCC sequence (OCC sequence number) based on the DMRS port (or the value of the Antenna port field) notified to terminal 200 by the Antenna port field. Here, the relationship between the OCC sequence number and the OCC sequence shown in FIG. 17 may be given by the relationship in FIGS. 8 and 9, for example.

[0097] For example, in a PUSCH using DFT-s-OFDM, when dmrs-Type = 1 (e.g., DMRS Configuration Type 1 is applied) and maxLength = 2 (e.g., double-symbol DMRS is allowed), the relationship between the value of the DCI bit field and the DMRS port is as shown in FIG. 18 .

[0098] In this embodiment, in addition to the relationship between the DCI bit field and the DMRS port shown in Fig. 18, the DMRS port (or the value of the DCI bit field) is associated with the OCC sequence number as shown in Fig. 19. As a result, terminal 200 determines the pre-DFT OCC sequence (OCC sequence number) based on the DMRS port (or the value of the Antenna port field) notified to terminal 200 by the Antenna port field.

[0099] 17 and 18 are merely examples, and the present invention is not limited to these. For example, as described in the first embodiment, the relationship between the DMRS ports and the OCC sequence numbers may be such that the output results (e.g., comb numbers, subcarriers or REs to which data signals are mapped) provided by the pre-DFT OCC and the comb structure in the frequency domain after DFT application are mapped to the subcarriers (or REs) used for the DMRS. Alternatively, the association between the DMRS ports and the OCC sequence numbers may not have the above relationship, or may have the above relationship in part.

[0100] [Example of Operation of Terminal 200] FIG. 20 is a flowchart showing an example of operation of determining an OCC sequence in terminal 200.

[0101] In FIG. 20, terminal 200 acquires information on the DMRS configuration and information on the DMRS port (S301).

[0102] Terminal 200 acquires information (for example, sequence length or spreading factor) related to the OCC sequence (pre-DFT OCC sequence) (S302).

[0103] The terminal 200 receives the DCI (S303).

[0104] Terminal 200 determines the DMRS port and OCC sequence associated with the value of the received DCI bit field (e.g., Antenna port field) based on the acquired information on the DMRS configuration and DMRS port, and the acquired information on the OCC sequence (S304).

[0105] According to the present embodiment, an OCC sequence can be reported using an existing DCI field (e.g., an Antenna port field), which enables dynamic reporting of an OCC sequence without increasing the number of DCI bits used for reporting the OCC sequence. Therefore, even in scenarios where coverage improvement is expected, for example, dynamic reporting of an OCC sequence can be achieved while suppressing an increase in DCI overhead.

[0106] In the case of a Configured Grant-PUSCH (CG-PUSCH) that transmits data in accordance with resource allocation instructed (or configured) by the RRC in layer 3, the DMRS port number is notified by the parameter "antennaPort" included in ConfiguredGrantConfig. In this case, terminal 200 may also determine the sequence of the pre-DFT PCC (OCC sequence number) based on the value of a parameter (e.g., antennaPort) instructed by the RRC, as in FIG. 17 or 19 .

[0107] In addition, in this embodiment, the OCC method is not limited to the OCC within an OFDM symbol using the above-mentioned pre-DFT OCC. For example, the OCC method to which this embodiment can be applied may be an OCC applied between OFDM symbols, an OCC applied between slots, or a combination thereof.

[0108] [Configuration of Base Station] Fig. 21 is a block diagram showing an example configuration of a base station 100. In Fig. 21 , the base station 100 includes a control unit 101, a higher-level control signal generation unit 102, a downlink control information generation unit 103, an encoding unit 104, a modulation unit 105, a signal allocation unit 106, a transmission unit 107, a reception unit 108, an extraction unit 109, a demodulation unit 110, and a decoding unit 111.

[0109] At least one of the transmitting unit 107 and the receiving unit 108 shown in Fig. 21 may be included in the communication unit shown in Fig. 2. Also, at least one of the control unit 101, the higher-level control signal generating unit 102, the downlink control information generating unit 103, the encoding unit 104, the modulation unit 105, the signal allocation unit 106, the receiving unit 108, the extraction unit 109, the demodulation unit 110, and the decoding unit 111 shown in Fig. 21 may be included in the control unit shown in Fig. 1.

[0110] The control unit 101, for example, determines information related to uplink transmission (e.g., PUSCH transmission) for terminal 200 and outputs the determined information to at least one of the higher control signal generation unit 102 and the downlink control information generation unit 103. The information related to PUSCH transmission may include, for example, information related to pre-DFT OCC (e.g., information related to OCC sequences such as OCC sequence length or spreading factor), information related to DMRS, time domain resource allocation information (e.g., TDRA), and frequency domain resource allocation information (e.g., FDRA). Furthermore, the control unit 101 outputs the determined information to the extraction unit 109, the demodulation unit 110, and the decoding unit 111.

[0111] Furthermore, the control unit 101 determines, for example, information related to a downlink signal for transmitting a higher control signal or downlink control information (for example, a modulation and coding scheme (MCS) and radio resource allocation), and outputs the determined information to the coding unit 104, the modulation unit 105, and the signal allocation unit 106. Furthermore, the control unit 101 outputs, for example, information related to the downlink signal (for example, a data signal or a higher control signal) to the downlink control information generation unit 103.

[0112] The upper control signal generating section 102 generates an upper layer control signal bit string based on information input from the control section 101 , for example, and outputs the upper layer control signal bit string to the encoding section 104 .

[0113] The downlink control information generating unit 103 generates a downlink control information (e.g., DCI) bit sequence based on, for example, information input from the control unit 101, and outputs the generated DCI bit sequence to the encoding unit 104. Note that control information may be transmitted to multiple terminals. For example, the downlink control information generating unit 103 may generate a DCI bit sequence (also referred to as a DCI sequence) including information related to a DMRS port and information related to an OCC sequence according to any of the above-described embodiments. Furthermore, the downlink control information generating unit 103 may add a CRC sequence scrambled by an RNTI (e.g., C-RNTI) to the DCI sequence.

[0114] For example, based on information input from the control unit 101, the coding unit 104 codes the bit sequence input from the higher control signal generation unit 102 or the DCI bit sequence input from the downlink control information generation unit 103. The coding unit 104 outputs the coded bit sequence to the modulation unit 105.

[0115] The modulation unit 105 modulates the coded bit sequence input from the coding unit 104, for example, based on information input from the control unit 101, and outputs the modulated signal (for example, a symbol sequence) to the signal allocation unit 106.

[0116] The signal allocation unit 106 maps the symbol sequence (including, for example, a downlink data signal or a control signal) input from the modulation unit 105 to the radio resource, for example, based on information indicating the radio resource input from the control unit 101. The signal allocation unit 106 outputs the downlink signal onto which the signal has been mapped to the transmission unit 107.

[0117] The transmitting unit 107 performs, for example, orthogonal frequency division multiplexing (OFDM) transmission waveform generation processing on the signal input from the signal allocating unit 106. Furthermore, in the case of OFDM transmission that adds a cyclic prefix (CP), the transmitting unit 107 performs inverse fast Fourier transform (IFFT) processing on the signal and adds the CP to the signal after the IFFT. Furthermore, the transmitting unit 107 performs RF processing, such as D / A conversion or up-conversion, on the signal and transmits the radio signal to the terminal 200 via an antenna.

[0118] The receiving unit 108 performs RF processing such as downconvert or A / D conversion on an uplink signal received from the terminal 200 via an antenna. In addition, in the case of OFDM transmission, the receiving unit 108 performs Fast Fourier Transform (FFT) processing on the received signal, for example, and outputs the resulting frequency domain signal to the extracting unit 109.

[0119] The extraction unit 109 extracts, for example, based on information input from the control unit 101, a radio resource portion from which an uplink signal (e.g., PUSCH) is transmitted, from the received signal input from the receiving unit 108, and outputs the extracted radio resource portion to the demodulation unit 110.

[0120] The demodulation unit 110 demodulates the uplink signal (e.g., PUSCH) input from the extraction unit 109, based on, for example, information input from the control unit 101. The demodulation unit 110 outputs the demodulation result to, for example, the decoding unit 111.

[0121] The decoding unit 111 performs error correction decoding of the uplink signal (e.g., PUSCH) based on, for example, information input from the control unit 101 and the demodulation result input from the demodulation unit 110, and obtains a decoded received bit sequence.

[0122] [Terminal Configuration] Fig. 22 is a block diagram showing an exemplary configuration of a terminal 200 according to an embodiment of the present disclosure. For example, in Fig. 22, the terminal 200 includes a receiving unit 201, an extracting unit 202, a demodulating unit 203, a decoding unit 204, a control unit 205, an encoding unit 206, a modulating unit 207, a signal allocating unit 208, and a transmitting unit 209.

[0123] At least one of the receiving unit 201 and the transmitting unit 209 shown in Fig. 22 may be included in the communication unit shown in Fig. 3. Also, at least one of the extracting unit 202, the demodulating unit 203, the decoding unit 204, the control unit 205, the encoding unit 206, the modulating unit 207, the signal allocating unit 208, and the transmitting unit 209 shown in Fig. 22 may be included in the control unit shown in Fig. 3.

[0124] The receiving unit 201 receives, for example, a downlink signal (e.g., a downlink data signal or downlink control information) from the base station 100 via an antenna, and performs RF processing such as downconverting or A / D conversion on the radio received signal to obtain a received signal (baseband signal). Furthermore, when receiving an OFDM signal, the receiving unit 201 performs FFT processing on the received signal to convert it into the frequency domain. The receiving unit 201 outputs the received signal to the extracting unit 202.

[0125] For example, based on information relating to the radio resource of the downlink control information input from the control unit 205, the extraction unit 202 extracts a radio resource portion that may include the downlink control information from the received signal input from the receiving unit 201, and outputs the extracted radio resource portion to the demodulation unit 203. Furthermore, based on information relating to the radio resource of the data signal input from the control unit 205, the extraction unit 202 extracts a radio resource portion that includes the downlink data signal, and outputs the extracted radio resource portion to the demodulation unit 203.

[0126] The demodulation unit 203 demodulates the signal (for example, PDCCH or PDSCH) input from the extraction unit 202 based on information input from the control unit 205 , for example, and outputs the demodulation result to the decoding unit 204 .

[0127] The decoding unit 204 performs error correction decoding of the PDCCH or PDSCH using, for example, the demodulation result input from the demodulation unit 203, and obtains, for example, an upper layer control signal or downlink control information. The decoding unit 204 outputs the upper layer control signal and the downlink control information to the control unit 205. Furthermore, the decoding unit 204 may generate a response signal (for example, ACK / NACK) based on the decoding result of the PDSCH.

[0128] The control unit 205 performs uplink transmission control (including, for example, specifying information about PUSCH repetition, such as a DMRS port for PUSCH transmission or a pre-DFT OCC sequence) according to the above-described method, based on, for example, information about PUSCH transmission obtained from a signal (for example, a higher layer control signal or downlink control information) input from the decoding unit 204. The control unit 205 outputs the determined information to, for example, the encoding unit 206 and the signal allocation unit 208.

[0129] The encoding unit 206 encodes an uplink data signal (UL data signal) or an uplink control signal, for example, based on information input from the control unit 205. The encoding unit 206 outputs the encoded bit string to the modulation unit 207.

[0130] The modulation unit 207 modulates, for example, the coded bit sequence input from the coding unit 206 and outputs the modulated signal (symbol sequence) to the signal allocation unit 208 .

[0131] The signal allocation unit 208 maps the signal (e.g., a sequence) input from the modulation unit 207 to a radio resource, for example, based on information input from the control unit 205. The signal allocation unit 208 outputs the uplink signal onto which the signal is mapped to the transmission unit 209, for example.

[0132] The transmitter 209 generates a transmission signal waveform, such as OFDM, for the signal input from the signal allocation unit 208. Furthermore, in the case of OFDM transmission using a CP, for example, the transmitter 209 performs IFFT processing on the signal and adds a CP to the signal after the IFFT. Alternatively, when the transmitter 209 generates a single-carrier waveform, a DFT unit (not shown) may be added after the modulator 207 or before the signal allocation unit 208. Furthermore, the transmitter 209 performs RF processing, such as D / A conversion and up-conversion, on the transmission signal, and transmits the radio signal to the base station 100 via an antenna.

[0133] (Other Embodiments) In the above-described embodiments, the DCI formats are not limited to DCI format 0-1 and DCI format 0-2, and other formats may be used. DCI format 0-0 may also be called, for example, a fallback DCI format. DCI format 0-1 may also be called, for example, a non-fallback DCI format. Furthermore, in the above-described embodiments, the types of information fields included in the DCI, the number of information fields, and the size (number of bits) of the information fields are merely examples, and DCI formats including information fields of other types, other numbers, or other sizes may also be used.

[0134] Furthermore, in each of the above-described embodiments, the channel used for uplink transmission (or the channel to which Repetition is applied) is not limited to PUSCH, but may be another channel. Furthermore, the type of information to be transmitted is not limited to data, but may be another type of information (for example, an uplink control signal (PUCCH)). Furthermore, an embodiment of the present disclosure is not limited to uplink transmission, but may be applied to downlink transmission or sidelink transmission.

[0135] The present disclosure may be applied to communication between terminals, such as sidelink communication, for example.

[0136] Furthermore, an embodiment of the present disclosure may be applied regardless of the type of satellite, such as a Geostationary Earth Orbit satellite (GEO), a Medium Earth Orbit satellite (MEO), a Low Earth Orbit satellite (LEO), or a Highly Elliptical Orbit satellite (HEO). Furthermore, an embodiment of the present disclosure may be applied to non-terrestrial communications, such as a HAPS or a drone base station.

[0137] Furthermore, although the above-described embodiment has been described using an NTN environment (e.g., a satellite communication environment) as an example, the present disclosure is not limited thereto. The present disclosure may be applied to other communication environments (e.g., a terrestrial cellular environment of at least one of LTE and NR). For example, one embodiment of the present disclosure may be applied to terrestrial communications in an environment where the cell size is large and the propagation delay between the base station 100 and the terminal 200 is longer (e.g., above a threshold).

[0138] In addition, in the above-described embodiment, the form of satellite communication may be a configuration in which the base station functions are located on a satellite (e.g., a "regenerative satellite"), or a configuration in which the base station functions are located on the ground and a satellite relays communication between the base station and a terminal (e.g., a "transparent satellite"). For example, in one embodiment of the present disclosure, the downlink and the uplink may be links between a terminal and a satellite, or links via a satellite.

[0139] Furthermore, in the present disclosure, the downlink control channel, downlink data channel, uplink control channel, and uplink data channel are not limited to PDCCH, PDSCH, PUCCH, and PUSCH, respectively, and may be control channels with other names.

[0140] Furthermore, in the present disclosure, RRC signaling is assumed as higher layer signaling, but it may be replaced with Medium Access Control (MAC) signaling and notification by DCI, which is physical layer signaling.

[0141] Furthermore, in the present disclosure, the orthogonal sequence is not limited to an OCC sequence (for example, a sequence obtained by cyclically shifting an OCC sequence) and may be another sequence. Furthermore, the reference signal associated with the orthogonal sequence is not limited to a DMRS and may be another reference signal. Furthermore, in the above embodiment, a case has been described in which the pre-DFT OCC, the output result after applying DFT, and the frequency resource used for the DMRS have a comb structure, but this is not limiting, and at least one may not have a comb structure.

[0142] The setting values ​​of parameters such as the number of allocated RBs, the number of subcarriers (or the number of REs) constituting one RB, the OCC sequence (e.g., sequence length, spreading factor, or sequence element), and the number of DMRS ports (e.g., maximum number) are not limited to the above examples and may be other values. Furthermore, the DMRS setting is not limited to DMRS Configuration Type 1 and may be other settings.

[0143] Furthermore, in the present disclosure, spreading using pre-DFT OCC may be applied in combination with other spreading methods (e.g., OCC applied between OFDM symbols or OCC applied between slots). For example, when multiplexing four UEs, an inter-slot OCC with an OCC sequence length of 2 and a pre-DFT OCC with a sequence length of 2 may be combined.

[0144] (Supplementary Note) Information indicating whether the terminal 200 supports the functions, operations, or processes described in each of the above-described embodiments and each supplementary note may be transmitted (or notified) from the terminal 200 to the base station 100, for example, as capability information or capability parameters of the terminal 200.

[0145] The capability information may include an information element (IE) that individually indicates whether or not the terminal 200 supports at least one of the functions, operations, or processes described in the above-described embodiments, modifications, and supplements. Alternatively, the capability information may include an information element that indicates whether or not the terminal 200 supports a combination of any two or more of the functions, operations, or processes described in the above-described embodiments, modifications, and supplements.

[0146] For example, the base station 100 may determine (or decide or assume) the functions, operations, or processes that the terminal 200 that transmitted the capability information supports (or does not support) based on the capability information received from the terminal 200. The base station 100 may perform operations, processes, or controls according to the determination result based on the capability information. For example, the base station 100 may control uplink-related processing based on the capability information received from the terminal 200.

[0147] Note that the fact that terminal 200 does not support some of the functions, operations, or processes described in the above-described embodiments, modifications, and supplementary notes may be interpreted as meaning that such some of the functions, operations, or processes are restricted in terminal 200. For example, information or a request regarding such restrictions may be notified to base station 100.

[0148] Information regarding the capabilities or limitations of terminal 200 may, for example, be defined in a standard, or may be implicitly notified to base station 100 in association with information known at base station 100 or information transmitted to base station 100.

[0149] The above has described the embodiments, modifications, and supplementary notes according to a non-limiting example of the present disclosure.

[0150] (Control Signal) In the present disclosure, a downlink control signal (or downlink control information) related to an embodiment of the present disclosure may be, for example, a signal (or information) transmitted in a Physical Downlink Control Channel (PDCCH) of a physical layer, or a signal (or information) transmitted in a Medium Access Control Control Element (MAC CE) or Radio Resource Control (RRC) of a higher layer. Furthermore, the signal (or information) is not limited to being notified by a downlink control signal, but may be predefined in a specification (or standard) or preconfigured in a base station and a terminal.

[0151] In the present disclosure, an uplink control signal (or uplink control information) related to an embodiment of the present disclosure may be, for example, a signal (or information) transmitted in a PUCCH of a physical layer, or a signal (or information) transmitted in a MAC CE or RRC of a higher layer. Furthermore, the signal (or information) is not limited to being notified by an uplink control signal, but may be predefined in a specification (or standard) or preconfigured in a base station and a terminal. Furthermore, the uplink control signal may be replaced with, for example, uplink control information (UCI), 1st stage sidelink control information (SCI), or 2nd stage SCI.

[0152] (Base Station) In an embodiment of the present disclosure, the base station may 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 parent device, a gateway, or the like. In sidelink communication, a terminal may play the role of a base station. Instead of a base station, a relay device that relays communication between an upper node and a terminal may be used. Alternatively, a roadside unit may be used.

[0153] (Uplink / Downlink / Sidelink) An embodiment of the present disclosure may be applied to, for example, any of the uplink, downlink, and sidelink. For example, an embodiment of the present disclosure may be applied to a Physical Uplink Shared Channel (PUSCH), a Physical Uplink Control Channel (PUCCH), or a Physical Random Access Channel (PRACH) in the uplink, a Physical Downlink Shared Channel (PDSCH), a PDCCH, or a Physical Broadcast Channel (PBCH) in the downlink, or a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Control Channel (PSCCH), or a Physical Sidelink Broadcast Channel (PSBCH) in the sidelink.

[0154] The PDCCH, PDSCH, PUSCH, and PUCCH are examples of a downlink control channel, a downlink data channel, an uplink data channel, and an uplink control channel, respectively. The PSCCH and PSSCH are examples of a sidelink control channel and a sidelink data channel. The PBCH and PSBCH are examples of a broadcast channel, and the PRACH is an example of a random access channel.

[0155] (Data Channel / Control Channel) An embodiment of the present disclosure may be applied to, for example, either a data channel or a control channel. For example, the channel in an embodiment of the present disclosure may be replaced with any of the data channels PDSCH, PUSCH, and PSSCH, or the control channels PDCCH, PUCCH, PBCH, PSCCH, and PSBCH.

[0156] (Reference Signal) In one embodiment of the present disclosure, a reference signal is, for example, a signal known by both a base station and a mobile station, and may also be called a Reference Signal (RS) or a pilot signal. The reference signal may be any of 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), or a Sounding Reference Signal (SRS).

[0157] (Time Interval) In one embodiment of the present disclosure, the unit of time resource is not limited to one or a combination of slots and symbols, but may be, for example, a time resource unit such as a frame, a superframe, a subframe, a slot, a time slot, a subslot, a minislot, a symbol, an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier-Frequency Division Multiplexing Access (SC-FDMA) symbol, or another time resource unit. Furthermore, the number of symbols included in one slot is not limited to the number of symbols exemplified in the above-mentioned embodiment, and may be another number of symbols.

[0158] (Frequency Band) An embodiment of the present disclosure may be applied to either a licensed band or an unlicensed band.

[0159] (Communication) An embodiment of the present disclosure may be applied to communication between a base station and a terminal (Uu link communication), communication between terminals (Sidelink communication), or Vehicle to Everything (V2X) communication. For example, the channel in an embodiment of the present disclosure may be replaced with any of PSCCH, PSSCH, Physical Sidelink Feedback Channel (PSFCH), PSBCH, PDCCH, PUCCH, PDSCH, PUSCH, or PBCH.

[0160] An embodiment of the present disclosure may be applied to a terrestrial network, a non-terrestrial network (NTN) using a satellite or a high altitude pseudo satellite (HAPS), or a terrestrial network in which transmission delay is large compared to the symbol length or slot length, such as a network with a large cell size or an ultra-wideband transmission network.

[0161] (SBFD) In ​​one embodiment of the present disclosure, operations on uplink, downlink, and sidelink symbols may be applied to symbols (e.g., SBFD symbols) on which SBFD (Subband Non-Overlapping Full Duplex, Subband Full Duplex) operations or controls are performed. In SBFD symbols, a frequency domain (or frequency resource, frequency band) is divided into multiple frequency domains (e.g., subbands, RB sets, subbands, or sub-BWPs (Bandwidth Parts)). A terminal transmits and receives in different directions (e.g., downlink or uplink) in units of subbands, which are the divided domains. In SBFD symbols, a terminal may transmit and receive in one direction, either uplink or downlink, but not in the other direction. On the other hand, a base station may be capable of transmitting and receiving on both the uplink and downlink simultaneously. SBFD symbols may have a smaller frequency domain available for downlink use than symbols that transmit and receive only downlink use. Also, SBFD symbols may have a smaller frequency domain available for uplink use than symbols that transmit and receive only uplink use.

[0162] In addition, in the SBFD symbol, a terminal may transmit and receive uplink and downlink simultaneously. In this case, the frequency domain in which the terminal transmits and the frequency domain in which the terminal receives may not be adjacent, but may be separated by a frequency interval (also called a frequency gap).

[0163] In addition, different transmission and reception directions in subband units, which are divided areas, may include transmission and reception of side links.

[0164] (XDD: Cross Division Duplex) In one embodiment of the present disclosure, the operation for uplink, downlink, and sidelink symbols may be applied to symbols (e.g., full duplex symbols) where full duplex operation or control is performed. In a full duplex symbol, both the terminal and the base station can simultaneously transmit and receive on the uplink and downlink. In a full duplex symbol, the terminal and the base station may simultaneously transmit and receive in an available frequency region (or frequency resource, frequency band), or may simultaneously transmit and receive in a partial frequency region (i.e., transmission or reception may be performed in other frequency regions). In this case, the frequency region in which the base station or terminal transmits and receives may not be adjacent, but may have a frequency interval (also called a frequency gap). Furthermore, for the purpose of, for example, reducing interference, either the terminal or the base station may simultaneously transmit and receive (i.e., the other may transmit or receive).

[0165] In addition, full duplex operation may be applied to an operation in which a terminal can simultaneously transmit and receive sidelinks, or to an operation in which a terminal can simultaneously transmit and receive sidelinks and uplinks or downlinks.

[0166] (Antenna Port) In one embodiment of the present disclosure, an antenna port refers to a logical antenna (antenna group) consisting 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 consisting of multiple antennas. For example, the number of physical antennas that an antenna port is composed of is not specified, and the antenna port may be specified as the smallest unit by which a terminal station can transmit a reference signal. Furthermore, an antenna port may also be specified as the smallest unit by which a weighting of a precoding vector is multiplied.

[0167] <5G NR System Architecture and Protocol Stack> The 5G NR system architecture generally assumes an NG-RAN (Next Generation - Radio Access Network) including gNBs. The gNBs provide UE-side termination of the NG radio access user plane (SDAP / PDCP / RLC / MAC / PHY) and control plane (RRC) protocols. The gNBs are connected to each other via an Xn interface. The gNBs are also connected to the Next Generation Core (NGC) via a Next Generation (NG) interface, more specifically to the Access and Mobility Management Function (AMF) (e.g., a specific core entity that performs AMF) via an NG-C interface, and to the User Plane Function (UPF) (e.g., a specific core entity that performs UPF) via an NG-U interface. The NG-RAN architecture is shown in Figure 23 (see, for example, 3GPP TS 38.300 v15.6.0, section 4).

[0168] <RRC connection setup and reconfiguration procedure> This shows the NAS part of the interaction between the UE, gNB, and AMF (5GC entity) when the UE transitions from RRC_IDLE to RRC_CONNECTED (see TS 38.300 v15.6.0).

[0169] RRC is a higher layer signaling protocol used to configure the UE and gNB. 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 an INITIAL CONTEXT SETUP REQUEST. The gNB then activates AS security together with the UE. This is done by the gNB sending a SecurityModeCommand message to the UE, and the UE responding with a SecurityModeComplete message to the gNB. The gNB then sends an RRCReconfiguration message to the UE, and upon receiving an RRCReconfigurationComplete from the UE, the gNB performs reconfiguration to set up Signaling Radio Bearer 2 (SRB2) and Data Radio Bearer (DRB). For signaling-only connections, the steps related to RRCReconfiguration are omitted because SRB2 and DRB are not set up. Finally, the gNB notifies the AMF that the setup procedure is complete with an INITIAL CONTEXT SETUP RESPONSE.

[0170] Therefore, the present disclosure provides a 5th Generation Core (5GC) entity (e.g., AMF, SMF, etc.) that includes: a control circuit that, upon operation, establishes a Next Generation (NG) connection with a gNodeB; and a transmitter that, upon operation, transmits an initial context setup message to the gNodeB via the NG connection so that a signaling radio bearer between the gNodeB and a user equipment (UE) is set up. Specifically, the gNodeB transmits Radio Resource Control (RRC) signaling, including a resource allocation configuration information element (IE), to the UE via the signaling radio bearer. The UE then transmits in uplink or receives in downlink based on the resource allocation configuration.

[0171] <QoS Control> The 5G Quality of Service (QoS) model is based on QoS flows and supports both QoS flows that require a guaranteed flow bit rate (Guaranteed Bit Rate QoS flows (GBR)) and QoS flows that do not require a guaranteed flow bit rate (non-GBR QoS flows). Thus, at the NAS level, a QoS flow is the finest granularity of QoS classification in a PDU session. A QoS flow is identified within a PDU session by a QoS Flow ID (QFI) carried in an encapsulation header over the NG-U interface.

[0172] For each UE, 5GC establishes one or more PDU sessions. For each UE, the NG-RAN establishes, for example, at least one Data Radio Bearer (DRB) for each PDU session. Additional DRBs for the QoS flows of that PDU session can be configured later (when this is up to the NG-RAN). The NG-RAN maps packets belonging to different PDU sessions to different DRBs. NAS-level packet filters in the UE and 5GC associate UL and DL packets with QoS flows, while AS-level mapping rules in the UE and NG-RAN associate UL and DL QoS flows with DRBs.

[0173] (Open-RAN) The base station described in each embodiment (for example, a 5G NR base station called a gNB) may be configured with three functional modules: a Centralized Unit (CU), a Distributed Unit (DU), and a Radio Unit (RU).

[0174] A CU may be referred to as a centralized node, aggregation node, central station, aggregation station, or centralized unit. A DU may be referred to as an O-RAN Distributed Unit (O-DU), distributed node, distributed station, or distributed unit. An RU may be referred to as an O-RAN Radio Unit (O-RU), radio equipment, radio node, radio station, antenna unit, or radio unit.

[0175] There are several split options for the functional split configuration (or functional split point) between CU, DU, and RU. The term "functional split point" is sometimes referred to as "split," "option," or "split option."

[0176] Examples of "division options" include the following division options 1 to 8. The functions of the base station described in each embodiment may be divided into a CU, a DU, and an RU by any of the following division options 1 to 8. For example, the CU, DU, and RU may be functionally divided, or the functions may be divided only between the CU and DU or only between the DU and RU. (1) Segmentation option 1: Between RRC (radio resource control) and PDCP (2) Segmentation option 2: Between PDCP and RLC (High-RLC) (3) Segmentation option 3: Between High-RLC and Low-RLC (4) Segmentation option 4: Between RLC (Low-RLC) and MAC (High-MAC) (5) Segmentation option 5: Between High-MAC and Low-MAC (6) Segmentation option 6: Between MAC (Low-MAC) and PHY (High-PHY) (7) Segmentation option 7: Between High-PHY and Low-PHY (8) Segmentation option 8: Between PHY (Low-PHY) and RF

[0177] The functional split point between the CU and O-DU may be split option 2. The section between the CU and O-DU is called midhaul, and the F1 interface is specified by 3GPP. The section between the O-DU and O-RU is called fronthaul, and the functional split point may be split option 7-2x, which is adopted as the O-RAN fronthaul specification.

[0178] Figure 24 shows an example of functionally dividing the gNB base station functions into CU, O-DU, and O-RU using Split Option 2 and Split Option 7-2x.

[0179] The CU may have, for example, a radio resource control (RRC) function, a service data adaptation protocol (SDAP) function, and a packet data convergence protocol (PDCP) function.

[0180] The O-DU may include, for example, a radio link control (RLC) function, a MAC function, and a higher physical layer (HIGH-PHY) function. The HIGH-PHY function may include an encoding function, a scrambling function, a modulation function, a layer mapping function, a precoding function, and a resource element (RE) mapping function for downlink (DL) transmission. The HIGH-PHY function may also include a decoding function, a descrambling function, a demodulation function, a layer demapping function, and a resource element (RE) demapping function for uplink (UL) reception.

[0181] The O-RU may have, for example, a LOW-PHY function and an RF function. The LOW-PHY function may also have, for downlink transmission, a beamforming function, an IFFT (Inverse First Fourier Transform) + CP (Cyclic Prefix) assignment function, and a D / A (Digital to Analog) conversion function. The LOW-PHY function may also have, for uplink reception, an A / D (Analog to Digital) conversion function, a CP removal + FFT (First Fourier Transform) function, and a beamforming function.

[0182] In addition, if the O-DU does not have a precoding function, the O-RU may have a precoding function.

[0183] The O-RU may have functionality related to LBT (listen before talk).

[0184] The evolving Common Public Radio Interface (eCPRI) is specified as the communication method between the O-DU and O-RU in Split Option 7-2x. In Split Option 7-2x, eCPRI transmits and receives sampling sequences of the in-phase (I) and quadrature (Q) components of OFDM signals in the frequency domain, as well as information used for beamforming in antennas and time synchronization signals.

[0185] Information transmitted by the signals described in each embodiment (PDCCH, PUCCH, PDSCH, PUSCH, MAC CE, RRC, etc.) may be transmitted between the O-DU and the O-RU via the eCPRI User Plane (U-Plane) or Control Plane (C-Plane).

[0186] When the functions described in each embodiment are performed in the O-RU by functional division, the O-DU may control the O-RU by transmitting information for controlling the functions via a control signal (e.g., eCPRI) between the O-DU and the O-RU.

[0187] When the functions described in each embodiment are performed in the O-DU by functional division, the O-RU may receive the results of the functions performed in the O-DU via a control signal (e.g., eCPRI) and control the O-RU based on the received results.

[0188] The CU, O-DU, and O-RU may be deployed in physically different devices with their respective functions connected by optical fiber or the like, or some or all of their functions may be deployed in the same physical device.

[0189] The CU and O-DU may be logical entities implemented as software running on a server in the cloud or the like as a virtualized RAN (virtual Radio Access Network: vRAN). Also, some or all of the functions of the CU and O-DU may be provided as a virtualized network function (Network Functions Virtualization: NFV) service.

[0190] The transceiver does not have to be a radio transceiver, but may be, for example, a network transceiver, an optical transceiver, etc. The radio resources allocated by the O-DU may be resources for wireless communication between the O-RU and the UE.

[0191] The present disclosure can be realized in software, hardware, or software in conjunction with hardware.

[0192] Each functional block used in the description of the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit, and each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of a single chip that includes some or all of the functional blocks. The LSI may have data input and output. Depending on the degree of integration, the LSI may also be called an IC, system LSI, super LSI, or ultra LSI.

[0193] The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, a field programmable gate array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells within the LSI, may be used. The present disclosure may be realized as digital processing or analog processing.

[0194] Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology may be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

[0195] The present disclosure may be implemented in any type of apparatus, device, or system (collectively referred to as a communications apparatus) that has a communications function. The communications apparatus may include a radio transceiver and processing / control circuitry. The radio transceiver may include a receiver and a transmitter, or both functions. The radio transceiver (transmitter and receiver) may include a radio frequency (RF) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or the like. Non-limiting examples of communication devices include telephones (e.g., cell phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communication-enabled vehicles or mobile transportation (e.g., cars, airplanes, ships), and combinations of the above devices.

[0196] The communication devices are not limited to portable or mobile devices, but also include any kind of non-portable or fixed equipment, devices, and systems, such as smart home devices (such as home appliances, lighting equipment, smart meters or measuring devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0197] Communications include data communications via cellular systems, wireless LAN systems, communication satellite systems, and the like, as well as data communications via combinations of these.

[0198] A communications apparatus also includes devices such as controllers and sensors connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0199] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0200] A terminal according to one embodiment of the present disclosure includes: a control circuit that determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal; and a transmission circuit that transmits the signal to which the orthogonal sequence has been applied.

[0201] In one embodiment of the present disclosure, the orthogonal sequence is a sequence obtained by cyclically shifting an Orthogonal Cover Code (OCC) sequence.

[0202] In one embodiment of the present disclosure, Demodulation Reference Signal (DMRS) configuration Type 1 is applied to the configuration of the demodulation reference signal.

[0203] In one embodiment of the present disclosure, the control circuit determines the orthogonal sequence having the relationship that the spacing of frequency resources in the comb structure of the output result is an integer multiple of the spacing of frequency resources used for the DMRS.

[0204] A terminal according to one embodiment of the present disclosure includes a control circuit that controls an allocation unit of frequency resources according to the length of an orthogonal sequence when the orthogonal sequence is applied to a signal before a Discrete Fourier Transform (DFT), and a transmission circuit that transmits the signal using the frequency resources allocated based on the allocation unit.

[0205] In a terminal according to one embodiment of the present disclosure, the allocation unit is a unit of N resource blocks, where N is the smallest integer such that the length of the orthogonal sequence is a multiple of 2 and a divisor of (12×N).

[0206] A terminal according to one embodiment of the present disclosure includes a control circuit that, when applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT), determines the orthogonal sequence based on a value of a field that indicates a port of a demodulation reference signal included in downlink control information, and a transmission circuit that transmits the signal to which the orthogonal sequence has been applied.

[0207] A base station according to one embodiment of the present disclosure includes: a control circuit that determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal; and a receiving circuit that receives the signal to which the orthogonal sequence has been applied.

[0208] In a communication method according to one embodiment of the present disclosure, a terminal determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal, and transmits the signal to which the orthogonal sequence has been applied.

[0209] In a communication method according to one embodiment of the present disclosure, a base station determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal, and receives the signal to which the orthogonal sequence has been applied.

[0210] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2024-022167, filed February 16, 2024, are incorporated herein by reference in their entirety.

[0211] One embodiment of the present disclosure is useful in wireless communication systems.

[0212] 100 Base station 101, 205 Control unit 102 Upper control signal generation unit 103 Downlink control information generation unit 104, 206 Encoding unit 105, 207 Modulation unit 106, 208 Signal allocation unit 107, 209 Transmission unit 108, 201 Reception unit 109, 202 Extraction unit 110, 203 Demodulation unit 111, 204 Decoding unit 200 Terminal

Claims

1. A terminal comprising: a control circuit that determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal; and a transmission circuit that transmits the signal to which the orthogonal sequence has been applied.

2. The terminal according to claim 1, wherein the orthogonal sequence is a sequence obtained by cyclically shifting an Orthogonal Cover Code (OCC) sequence.

3. The terminal according to claim 1, wherein Demodulation Reference Signal (DMRS) configuration Type 1 is applied to the configuration of the demodulation reference signal.

4. The terminal according to claim 3, wherein the control circuit determines the orthogonal sequence having the relationship such that the spacing of frequency resources in the comb structure of the output result is an integer multiple of the spacing of frequency resources used for the DMRS.

5. A terminal comprising: a control circuit that controls an allocation unit of frequency resources according to the length of an orthogonal sequence when applying the orthogonal sequence to a signal before a Discrete Fourier Transform (DFT); and a transmission circuit that transmits the signal using the frequency resources allocated based on the allocation unit.

6. The terminal according to claim 5, wherein the allocation unit is a unit of N resource blocks, and N is the smallest integer that makes the length of the orthogonal sequence a multiple of 2 and a divisor of (12×N).

7. A terminal comprising: a control circuit that, when applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT), determines the orthogonal sequence based on the value of a field that notifies a port of a demodulation reference signal included in downlink control information; and a transmission circuit that transmits the signal to which the orthogonal sequence has been applied.

8. A base station comprising: a control circuit that determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal; and a receiving circuit that receives the signal to which the orthogonal sequence has been applied.

9. A communication method in which a terminal determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal, and transmits the signal to which the orthogonal sequence has been applied.

10. A communication method in which a base station determines an orthogonal sequence having a relationship such that at least a portion of a frequency domain output result obtained by applying an orthogonal sequence to a signal before a Discrete Fourier Transform (DFT) and applying the DFT to the signal is mapped to a frequency resource used for a demodulation reference signal, and receives the signal to which the orthogonal sequence has been applied.

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