Terminal and communication method

Abstract

A terminal comprising a control circuit for controlling communications in units of a second symbol, each unit being associated with a plurality of first symbols, and a communication circuit for performing communications.

Description

[Technical field]

[0001] The present disclosure relates to a terminal and a communication method. [Background technology]

[0002] In recent years, the Internet of Things (IoT) is expected to develop rapidly against the backdrop of the expansion and diversification of wireless services, and the use of mobile communications is expanding to all fields, such as cars, homes, home appliances, and industrial equipment, in addition to information terminals such as smartphones. In order to support the diversification of services, a significant improvement in the performance and functions of mobile communication systems is required to meet various requirements, such as an increase in the number of connected devices and low latency, in addition to an increase in system capacity. In response to this background, the 5th Generation mobile communication systems (5G), which are being researched, developed, and standardized, can provide flexible wireless communication according to a wide variety of needs by enhancing mobile broadband (eMBB: enhanced Mobile Broadband), connecting multiple devices (mMTC: massive Machine Type Communication), and ultra-reliable and low latency communication (URLLC: ultra-reliable and low latency communication).

[0003] The 3rd Generation Partnership Project (3GPP), an international standardization organization, is working on specifications for New Radio (NR) as one of the 5G wireless interfaces. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP TS38.104 V15.8.0, “NR Base Station (BS) radio transmission and reception (Release 15),” 2019-12. [Non-licensed document 2] RP-193240, “New SID on NR coverage enhancement,” China Telecom, December 2019. [Non-licensed document 3] 3GPP TS 38.211 V15.8.0, "NR; Physical channels and modulation (Release 15)," 2019-12.

Non-licensed Document 4

Non-licensed Document 5

Non-licensed Document 6

Non-licensed Document 7

[0005] However, there is room for improvement in the accuracy of channel estimation in wireless communication.

[0006] Non-limiting embodiments of the present disclosure contribute to providing a terminal and a communication method capable of improving the accuracy of channel estimation in wireless communication.

[0007] A terminal according to an embodiment of the present disclosure includes a control circuit that controls communication in units of second symbols, each of which corresponds to a plurality of first symbols, and a communication circuit that performs the communication.

[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 an embodiment of the present disclosure, it is possible to improve the accuracy of channel estimation in wireless communication.

[0010] Further advantages and benefits of an embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some of the 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. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 illustrates an example of a time domain resource configuration. [Diagram 2] FIG. 1 shows an example of downlink data transmission. [Diagram 3] FIG. 1 shows an example of uplink data transmission. [Figure 4] A diagram showing an example of repetition of the Physical Downlink Shared Channel (PDSCH) [Diagram 5] A diagram showing an example of repetition of the Physical Uplink Shared Channel (PUSCH) [Figure 6] Diagram showing an example of the arrangement of Additional Demodulation Reference Signal (DMRS) [Figure 7] Diagram showing an example of Additional DMRS placement [Figure 8] Block diagram showing an example of a partial configuration of a terminal [Figure 9] Block diagram showing a configuration example of a base station [Figure 10] Block diagram showing an example of a terminal configuration [Figure 11] FIG. 1 shows an example of the configuration of virtual symbols and virtual slots. [Figure 12] A diagram showing an example of the configuration of virtual symbols and virtual slots related to Option FS-1. [Figure 13] FIG. 1 shows an example of the configuration of virtual symbols and virtual slots related to Option FS-1-1. [Figure 14] FIG. 1 shows an example of the configuration of virtual symbols and virtual slots related to Option FS-1-2. [Figure 15] FIG. 1 shows an example of the configuration of virtual symbols and virtual slots related to Option FS-1-3. [Figure 16] A diagram showing an example of the configuration of a virtual slot for Option FS-2 [Figure 17] FIG. 1 shows an example of PDSCH resource allocation for Option RA-1 [Figure 18]FIG. 1 shows an example of PUSCH resource allocation for Option RA-1. [Figure 19] FIG. 1 shows an example of PUCCH resource allocation for Option RA-1. [Figure 20] FIG. 1 shows an example of PDSCH resource allocation for Option RA-2 [Figure 21] FIG. 1 shows an example of PDSCH resource allocation for Option RA-3 [Figure 22] A diagram showing an example of DMRS arrangement related to Option DMRS-1 [Figure 23] A diagram showing an example of DMRS arrangement related to Option DMRS-2 [Figure 24] A diagram showing an example of repetition related to Option R-1 [Diagram 25] A diagram showing an example of repetition related to Option R-2 [Figure 26] A diagram showing an example of repetition related to Option R-3 [Figure 27] Flowchart showing an example of PDSCH reception and PUCCH transmission operations in a terminal [Figure 28] Flowchart showing an example of a PUSCH transmission operation in a terminal [Figure 29] FIG. 1 is an example architecture diagram of a 3GPP NR system. [Diagram 30] Schematic showing the functional separation between NG-RAN and 5GC [Diagram 31] Sequence diagram of Radio Resource Control (RRC) connection setup / reconfiguration procedure [Diagram 32] A schematic diagram showing the usage scenarios of enhanced Mobile BroadBand (eMBB), massive Machine Type Communications (mMTC), and Ultra Reliable and Low Latency Communications (URLLC). [Diagram 33]Block diagram illustrating an example 5G system architecture for a non-roaming scenario DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

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

[0013] In NR, in addition to a frequency band of 6 GHz or less (also called, for example, Frequency Range 1 (FR1)), such as 700 MHz to 3.5 GHz, which has been used for cellular communication, millimeter wave bands such as 28 GHz or 39 GHz (also called, for example, FR2) that can secure a wide band may be utilized (see, for example, Non-Patent Document 1). Also, for example, in FR1, a frequency band such as 3.5 GHz, which is higher than the frequency band used in Long Term Evolution (LTE) or 3rd Generation mobile communication systems (3G), may be used. The higher the frequency band, the greater the radio wave propagation loss, and the more likely the radio wave reception quality is to deteriorate. For this reason, in NR, when a frequency band higher than LTE or 3G is used, a method is being considered for securing a communication area (or coverage) equivalent to that of a radio access technology (RAT) such as LTE or 3G, in other words, securing appropriate communication quality (see, for example, Non-Patent Document 2).

[0014] [Time Domain Resources] In NR, time domain resources such as slots, subframes, and frames may be configured by time resource units such as multiple Orthogonal Frequency Division Multiplexing (OFDM) symbols. For example, a slot may be configured by multiple OFDM symbols (for example, 14 in the case of Normal cyclic prefix (CP)) regardless of the subcarrier spacing (SCS), a subframe may be defined as a 1 ms interval, and a frame may be defined by 10 subframes (for example, see Non-Patent Document 3). Note that a slot may be understood to correspond to a unit time interval corresponding to a scheduling unit. FIG. 1 is a diagram showing an example of the configuration of time domain resources such as symbols (for example, OFDM symbols), slots, subframes, and frames. FIG. 1 shows an example of the configuration when the subcarrier spacing (SCS) is 15 kHz and when it is 30 kHz.

[0015] In addition, in NR, for example, a terminal (also referred to as, for example, UE: User Equipment) transmits and receives data in accordance with resource allocation indicated by a layer 1 control signal (e.g., DCI: Downlink Control Information) in a downlink control channel (e.g., PDCCH: Physical Downlink Control Channel) from a base station (also referred to as, for example, gNB) (see, for example, Non-Patent Documents 4-6).

[0016] For example, in the downlink, the base station may allocate a downlink data channel (e.g., a Physical Downlink Shared Channel (PDSCH)) and transmit DCI for the PDSCH by the PDCCH. The terminal may receive and decode the PDCCH, and may receive, demodulate, and decode the PDSCH based on control information included in the PDCCH (e.g., DCI).

[0017] Here, regarding the allocation of the PDSCH, the control information included in the DCI may include, for example, information about the time domain resource to which the PDSCH is allocated. The information about the time domain resource may include, for example, information about the timing (e.g., the number of slots "K0") after the slot in which the terminal receives the PDCCH, the position of the first symbol of the PDSCH in the slot (e.g., the start symbol "S PDSCH "), or the number of symbols to which the PDSCH is assigned (for example, the number of symbols "L PDSCH ") is acceptable.

[0018] In addition, the terminal may, for example, feed back a response signal (ACK / NACK: Acknowledgement / Negative Acknowledgement, or also called Hybrid Automatic Repeat Request (HARQ)-ACK) indicating the success or failure of decoding of the PDSCH to the base station using an uplink control channel (for example, PUCCH: Physical Uplink Control Channel) (for example, see Non-Patent Document 5).

[0019] Furthermore, the terminal may transmit downlink channel state information (e.g., CSI: Channel State Information) and uplink radio resource allocation request (e.g., SR: Scheduling Request) to the base station in addition to ACK / NACK, for example, by using PUCCH. The ACK / NACK, CSI, and SR are also called uplink control information (e.g., UCI: Uplink Control Information).

[0020] Also, for example, when transmitting an ACK / NACK for a PDSCH allocated by DCI, the terminal may transmit a PUCCH including the ACK / NACK in accordance with resource allocation indicated by DCI from the base station.

[0021] Here, regarding the allocation of PUCCH, the control information included in DCI may include, for example, information on PUCCH resources. The PUCCH resources may be configured, for example, by a plurality of parameters. Among the parameters configuring the PUCCH resources, the information on the time domain resources may be, for example, information on the PUCCH first symbol position in a slot (for example, the starting symbol "startingSymbolIndex") and the number of symbols by which the PUCCH is transmitted (for example, the number of symbols "nrofSymbols"). Furthermore, the control information included in DCI may include information on the timing of transmitting the PUCCH after how many slots from the slot in which the PDSCH is received (for example, the number of slots "k").

[0022] Furthermore, for CSI or SR, for example, a PUCCH resource may be specified (in other words, configured, notified, or indicated) from a base station by a higher layer signal (also called a radio resource control (RRC) signal, higher layer signaling, or higher layer parameter).

[0023] FIG. 2 is a diagram showing an example of allocation of time domain resources of PDCCH, PDSCH, and PUCCH in downlink data transmission. In FIG. 2, as an example, K0=0, S PDSCH =2, L PDSCH = 12, k = 2, startingSymbolIndex = 7, and nrofSymbols = 7. In FIG. 2, for example, the 14 symbols in a slot may be assigned symbol numbers 0 to 13 (for example, symbols #0 to #13). In FIG. 2, for example, the PDSCH is assigned from the S in the slot K0 = 0 slots after the slot in which the terminal receives the PDCCH (in other words, the slot in which the PDCCH is received). PUSCH =2nd symbol to L PUSCH2, for example, the PUCCH is transmitted in nrofSymbols=7 symbols (for example, symbols #7 to #13) starting from the symbol with startingSymbolIndex=7 in the slot k=2 slots after the slot in which the terminal received the PDSCH.

[0024] Also, for example, in the uplink, the terminal may transmit an uplink data channel (e.g., PUSCH: Physical Uplink Shared Channel) in accordance with a resource allocation (e.g., Grant) indicated by DCI in the PDCCH from the base station (see, for example, Non-Patent Documents 4-6).

[0025] Here, regarding the allocation of the PDSCH, the control information included in the DCI may include, for example, information about the time domain resource for transmitting the PUSCH. The information about the time domain resource may include, for example, information about the timing of how many slots after the slot in which the terminal receives the PDCCH the PUSCH is transmitted (for example, the number of slots "K2"), the position of the first symbol of the PUSCH in the slot (for example, the start symbol "S PUSCH "), or the number of symbols to transmit the PUSCH (for example, the number of symbols "L PUSCH ") is acceptable.

[0026] FIG. 3 is a diagram showing an example of allocation of time domain resources for PDCCH and PUSCH in uplink data transmission. In FIG. 3, as an example, K2=2, S PUSCH =0, L PUSCH In FIG. 3, for example, the 14 symbols in a slot may be assigned symbol numbers 0 to 13 (for example, symbols #0 to #13). In FIG. 3, for example, the PUSCH is assigned to the S in the slot K2=2 slots after the slot in which the terminal receives the PDCCH. PUSCH =0th symbol to L PUSCH = 14 symbols (eg, symbols #0 to #13).

[0027] Furthermore, NR supports grant-free transmission (or configured grant transmission) in which a terminal transmits a PUSCH using resources designated (or configured) in advance without receiving an allocation (e.g., grant) from a base station (see, for example, Non-Patent Documents 4 or 6). Methods of designating resources in grant-free transmission include, for example, "Type 1" in which transmission parameters such as the transmission resource period or time domain resources are preset by higher layer signals (e.g., RRC), and "Type 2" in which the designation of some transmission parameters such as time domain resources can be changed semi-fixedly by DCI.

[0028] [Channel Estimation] In NR, for example, a reference signal (e.g., Demodulation Reference Signal (DMRS)) used for channel estimation for demodulation may be arranged in resources of PDCCH, PDSCH, PUCCH, and PUSCH. The DMRS may be arranged, for example, in the front of a slot. Also, the DMRS may be arranged, for example, in multiple symbols in a slot (see, for example, Non-Patent Documents 3, 5, or 6).

[0029] Also, in NR Rel.15, for example, PDSCH, PUCCH, and PUSCH may be repeatedly transmitted (also called repetition) using multiple slots (for example, in slot units) (see, for example, Non-Patent Documents 5 or 6). For example, information on whether or not the terminal applies repetition and the number of repetitions (for example, the number of slots) in the case of repeated transmission may be semi-statically notified from the base station to the terminal by a terminal-specific higher layer signal (for example, an RRC signal). Also, when repetition is applied, for example, a common time domain resource allocation may be applied in multiple slots.

[0030] FIG. 4 is a diagram showing an example of PDSCH repetition in NR Rel. 15. PDSCH =2, LPDSCH 4 shows an example in which the repetition count is set to 2 slots and the time domain resource allocation (in other words, symbol allocation) is applied to the PDSCH to which repetition is applied in the slots corresponding to the first and second repetition intervals. Note that the above intervals may be read as "transmission interval" or "transmission occasion or transmission opportunity."

[0031] In the following description, this type of repetition method is called "slot-based repetition."

[0032] In addition, NR Rel.16 specifies a method of repeatedly transmitting one or more PUSCHs per slot for PUSCH transmission (see, for example, Non-Patent Document 7). In this method, for example, a base station transmits a PUSCH for the first time (in other words, the first time) to a terminal (for example, the 1st Allocation of time domain resources to K2, S PUSCH and L PUSCH In this method, the allocation of time domain resources for second and subsequent PUSCH transmissions may be, for example, consecutive and the same number of symbols as in the previous PUSCH transmission.

[0033] FIG. 5 is a diagram showing an example of PUSCH repetition in NR Rel. 16. PUSCH =0, L PUSCH 5 shows an example in which the repetition count is set to 7 and the number of repetitions is set to 4. As shown in FIG. 5, for a PUSCH to which repetition is applied, in the second and subsequent repetition periods, the same number of symbols (e.g., 7 symbols) as those of the previous PUSCH transmission are allocated consecutively.

[0034] In the following description, such a repetition method is referred to as “minislot-based repetition.” Note that a minislot may be understood as, for example, a time resource unit shorter than a slot.

[0035] Here, the lower the communication quality indicator, such as the signal-to-noise power ratio (SNR) or the signal-to-interference plus noise power ratio (SINR), to which Coverage Enhancement (CE) can be applied, the more likely it is that channel estimation accuracy will deteriorate.

[0036] In order to improve coverage, for example, the introduction of the above-mentioned Repetition is expected, but in NR, for example, there is a provision that a channel estimation result demodulated by a DMRS can be used in a slot that includes the DMRS. In other words, in this provision, a channel estimation result by the DMRS is not used in a slot other than the slot that includes the DMRS.

[0037] Therefore, in the above-mentioned Repetition in NR, a method may be adopted as a receiving process in which, for example, channel estimation is performed for each slot, and the data for each slot is demodulated and decoded using the obtained channel estimation value for each slot, and then the output of the decoding result (for example, Log Likelihood Ratio (LLR)) is synthesized.

[0038] In this method, for example, it is possible to combine the output results (e.g., LLR) of each slot for data. On the other hand, in this method, since channel estimation is performed for each slot, it is difficult to improve the channel estimation accuracy. For example, if data demodulation and decoding of each slot is performed using a channel estimation value with reduced estimation accuracy, there is a possibility that the combining gain by repetition cannot be obtained sufficiently. Therefore, it is expected to improve the channel estimation accuracy in repetition.

[0039] One method for improving the accuracy of channel estimation is, for example, applying Additional DMRS allocation adopted in NR. In this method, for example, as shown in Fig. 6, DMRS may be allocated to multiple symbols in a slot. However, when Additional DMRS is used, the overhead of DMRS is likely to increase, and transmission efficiency may decrease.

[0040] Furthermore, even in the above-mentioned PUSCH repetition of NR Rel.16 (for example, minislot-based repetition), a DMRS is arranged in each of a plurality of repetition intervals as shown in Fig. 7, and the number of DMRS symbols in one slot can be increased, so that it can be said to be a method capable of improving channel estimation accuracy. However, in the PUSCH repetition of NR Rel.16, for example, a DMRS is arranged in each repetition interval, so that the overhead of the DMRS increases and the transmission efficiency may decrease, as in the case of applying Additional DMRS.

[0041] Also, as another example of a method for improving the accuracy of channel estimation, for example, a method of performing channel estimation by combining DMRSs of multiple slots can be mentioned. For example, the above-mentioned channel estimation result demodulated by the DMRS can be used not only in the slot containing the DMRS but also in other slots, thereby improving the reception SNR of the DMRS used for channel estimation (in other words, inter-slot channel estimation). However, since inter-slot channel estimation allows channel estimation after receiving multiple slots that combine DMRSs, there is a possibility that the processing delay of decoding and demodulating data increases. For this reason, inter-slot channel estimation may not be able to take advantage of the advantage of reducing the delay of demodulation processing by front-load DMRS adopted in NR, for example. Also, for example, in an environment where coverage extension may be applied (for example, an environment where a terminal moves), the effect of inter-slot channel estimation may be smaller than in an environment where coverage extension is not applied.

[0042] In one non-limiting embodiment of the present disclosure, for example, a method (which may be referred to as a "framework") for improving channel estimation accuracy in wireless communication including Repetition will be described.

[0043] [Communication system overview] The communication system according to each embodiment of the present disclosure includes a base station 100 and a terminal 200.

[0044] Fig. 8 is a block diagram showing a configuration example of a part of a terminal 200 according to an embodiment of the present disclosure. In the terminal 200 shown in Fig. 8, a control unit 205 (e.g., corresponding to a control circuit) controls communication in units of second symbols (e.g., "virtual symbols" described later) in which a plurality of first symbols (e.g., "normal symbols" described later) are associated with one unit, and a receiving unit 201 and a transmitting unit 209 (e.g., corresponding to a communication circuit) perform the above communication.

[0045] [Base station configuration] Fig. 9 is a block diagram showing an example of the configuration of a base station 100 according to embodiment 1. In Fig. 9, the base station 100 includes a control unit 101, a higher level control signal generating unit 102, a downlink control information generating unit 103, an encoding unit 104, a modulation unit 105, a signal allocation unit 106, a transmitting unit 107, a receiving unit 108, an extraction unit 109, a demodulation unit 110, and a decoding unit 111.

[0046] The control unit 101 determines, for example, information on “symbol-based Repetition” for the terminal 200 , and outputs the determined information to the higher-level control signal generation unit 102 or the downlink control information generation unit 103 .

[0047] An example of the repetition in symbol units will be described later.

[0048] Furthermore, control section 101 determines, for example, information on PDSCH reception, information on PUSCH transmission, and information on PUCCH transmission for terminal 200, and outputs the determined information to higher control signal generating section 102. The information on PDSCH reception and the information on PUSCH transmission may include, for example, information on Time Domain Resource Allocation (TDRA). The information on TDRA (hereinafter sometimes referred to as "TDRA information") may be represented in a table format (TDRA table). Furthermore, the information on PUCCH transmission may include, for example, information on a PUCCH resource set (for example, PUCCH resource candidates).

[0049] Furthermore, the control unit 101 determines information on a downlink signal for transmitting, for example, a downlink data signal (for example, a PDSCH), a higher control signal (for example, an RRC signal), or downlink control information (for example, DCI). The information on the downlink signal may include, for example, information such as a modulation and coding scheme (MCS) and radio resource allocation. The control unit 101 outputs, for example, the determined information to the encoding unit 104, the modulation unit 105, and the signal allocation unit 106. Furthermore, the control unit 101 outputs, for example, information on the downlink signal, such as a data signal or a higher control signal, to the downlink control information generation unit 103.

[0050] Furthermore, the control unit 101 determines, for example, a PUCCH resource for terminal 200 to transmit an uplink control signal (for example, a PUCCH) and outputs information on the determined resource to, for example, the extraction unit 109, the demodulation unit 110, and the decoding unit 111.

[0051] In addition, the control unit 101 determines, for example, information (e.g., modulation and coding scheme (MCS) and radio resource allocation) regarding the uplink signal used by the terminal 200 to transmit an uplink data signal (e.g., PUSCH), and outputs the determined information to the downlink control information generation unit 103, the extraction unit 109, the demodulation unit 110, and the decoding unit 111.

[0052] In addition, the control unit 101 may determine the above-mentioned information regarding the downlink signal, information regarding the PUCCH resource, or information regarding the uplink signal based on, for example, a method described later (for example, a method such as resource allocation, DMRS placement, or additional repetition).

[0053] The upper layer control signal generating section 102 generates an upper layer control signal bit sequence based on information input from the control section 101 , for example, and outputs the upper layer control signal bit sequence to the encoding section 104 .

[0054] The downlink control information generating unit 103 generates a downlink control information (e.g., DCI) bit string based on, for example, information input from the control unit 101, and outputs the generated DCI bit string to the encoding unit 104. Note that the control information may be transmitted to multiple terminals.

[0055] For example, based on information input from the control unit 101, the encoding unit 104 encodes downlink data (for example, a DL data signal), a bit sequence input from the higher control signal generating unit 102, or a DCI bit sequence input from the downlink control information generating unit 103. The encoding unit 104 outputs the encoded bit sequence to the modulation unit 105.

[0056] The modulation unit 105 modulates the encoded bit sequence input from the encoding 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.

[0057] 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 based on, for example, information indicating the radio resource input from the control unit 101. The signal allocation unit 106 outputs the downlink signal to which the signal has been mapped to the transmission unit 107.

[0058] The transmitting unit 107 performs, for example, a transmission waveform generation process such as orthogonal frequency division multiplexing (OFDM) on the signal input from the signal allocation unit 106. In addition, in the case of OFDM transmission that adds a cyclic prefix (CP), the transmitting unit 107 performs an inverse fast Fourier transform (IFFT) process on the signal and adds a CP to the signal after the IFFT. In addition, the transmitting unit 107 performs, for example, RF processes such as D / A conversion and up-conversion on the signal, and transmits the wireless signal to the terminal 200 via an antenna.

[0059] The receiving unit 108 performs RF processing such as down-convert 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, and outputs the obtained frequency domain signal to the extracting unit 109.

[0060] The extraction unit 109 extracts a radio resource portion from which an uplink signal (e.g., PUSCH or PUCCH) transmitted by the terminal 200 is transmitted based on, for example, information input from the control unit 101, and outputs the extracted radio resource portion to the demodulation unit 110.

[0061] The demodulation unit 110 performs channel estimation using a reference signal (e.g., DMRS) included in the received signal input from the extraction unit 109, based on, for example, information input from the control unit 101. Furthermore, the demodulation unit 110 demodulates the uplink signal (e.g., PUSCH or PUCCH) input from the extraction unit 109, using, for example, the channel estimation result. The demodulation unit 110 outputs, for example, the demodulation result to the decoding unit 111.

[0062] The decoding unit 111 performs error correction decoding of an uplink signal (e.g., PUSCH or PUCCH) based on, for example, information input from the control unit 101 and a demodulation result input from the demodulation unit 110, and obtains a decoded received bit sequence (e.g., a UL data signal or UCI).

[0063] [Device configuration] 10 is a block diagram showing a configuration example of a terminal 200 according to an embodiment of the present disclosure. For example, in FIG. 10, 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.

[0064] The receiver 201 receives, for example, a downlink signal (for example, a downlink data signal or downlink control information) from the base station 100 via an antenna, and performs RF processing such as downconvert or A / D conversion on the wireless received signal to obtain a received signal (baseband signal). When receiving an OFDM signal, the receiver 201 performs FFT processing on the received signal to convert the received signal into the frequency domain. The receiver 201 outputs the received signal to the extractor 202.

[0065] For example, based on information on 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. Also, based on information on the radio resource of the data signal input from the control unit 205, the extraction unit 202 extracts a radio resource portion that includes downlink data, and outputs the extracted radio resource portion to the demodulation unit 203.

[0066] Demodulation section 203 performs channel estimation using a reference signal (e.g., DMRS) included in the received signal input from extraction section 202, based on information input from control section 205, for example. Also, demodulation section 203 demodulates a signal (e.g., PDCCH or PDSCH) input from extraction section 202, for example, using the channel estimation result, and outputs the demodulation result to decoding section 204.

[0067] The decoding unit 204 performs error correction decoding on the demodulation result input from the demodulation unit 203, for example, to obtain downlink reception data, a higher layer control signal, or downlink control information. The decoding unit 204 outputs the higher layer control signal and the downlink control information to the control unit 205, and outputs the downlink reception data. The decoding unit 204 may also generate a response signal (for example, ACK / NACK) based on the decoding result of the downlink reception data, and output the response signal to the encoding unit 206.

[0068] The control unit 205 determines radio resources for PDSCH reception, PUSCH transmission, or PUCCH transmission, for example, based on a signal (for example, a higher layer control signal or downlink control information) input from the decoding unit 204. Note that the control unit 205 may determine the above-mentioned radio resources, for example, based on a method described later (for example, a method such as resource allocation, DMRS allocation, or additional repetition). The control unit 205 outputs the determined information to, for example, the extraction unit 202, the demodulation unit 203, the encoding unit 206, and the signal allocation unit 208.

[0069] The encoding unit 206 encodes an uplink signal (for example, UCI or an uplink data signal) based on information input from the control unit 205, and outputs the encoded bit sequence to the modulation unit 207. Note that encoding may not be performed depending on the PUCCH format.

[0070] 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 .

[0071] The signal allocation unit 208 maps the signal input from the modulation unit 207 to radio resources based on, for example, information input from the control unit 205, and outputs the uplink signal to which the signal has been mapped to the transmission unit 209.

[0072] The transmitting unit 209 generates a transmission signal waveform, such as OFDM, for the signal input from the signal allocating unit 208. In addition, in the case of OFDM transmission using a CP, for example, the transmitting unit 209 performs IFFT processing on the signal and adds a CP to the signal after IFFT. Alternatively, in the case of generating a single carrier waveform, the transmitting unit 209 may add a DFT (Discrete Fourier Transform) unit (not shown) after the modulating unit 207 or before the signal allocating unit 208. In addition, the transmitting unit 209 performs RF processing, such as D / A conversion and up-conversion, on the transmission signal, and transmits a radio signal to the base station 100 via an antenna.

[0073] [Example of Operation of Base Station 100 and Terminal 200] An example of the operation of base station 100 and terminal 200 having the above configuration will be described.

[0074] In this embodiment, for example, "symbol-based repetition" different from the above-mentioned slot-based repetition or minislot-based repetition is applied. Symbol-based repetition is, for example, repetition in which the same OFDM symbol is transmitted continuously.

[0075] In the symbol-based repetition, it is easier to perform in-phase synthesis of DMRS symbols and data symbols transmitted continuously in the time domain compared to, for example, slot-based or minislot-based repetition, so that the received SNR of the combined DMRS can be improved. Therefore, for example, by using the combined DMRS for channel estimation, the accuracy of channel estimation can be improved.

[0076] In addition, in this embodiment, when applying symbol-based repetition, a "virtual symbol" consisting of a plurality of OFDM symbols repeated on a symbol-by-symbol basis, and a "virtual slot" consisting of a plurality of virtual symbols are introduced as a time resource unit.

[0077] In the following description, symbols (e.g., OFDM symbols) and slots to which symbol-based Repetition is not applied may be referred to as “normal symbols” and “normal slots” to distinguish them from virtual symbols and virtual slots.

[0078] For example, in this embodiment, a case will be described in which one or more NR physical layer processes, such as the above-mentioned resource allocation, DMRS placement, slot-based repetition, or minislot-based repetition, are realized by applying virtual symbols or virtual slots.

[0079] For example, by replacing symbol- or slot-based NR physical layer processing with virtual symbols or virtual slots, it is possible to suppress changes to the NR physical layer processing and realize symbol-based repetition. The physical layer processing may include, for example, resource allocation processing, DMRS-related processing, timing-related processing, or power control processing.

[0080] In other words, base station 100 and terminal 200 control communications based on at least one of units of "Virtual symbols" (e.g., corresponding to the second symbol) in which multiple Normal symbols (e.g., corresponding to the first symbol) correspond to one unit, and units of "Virtual slots" composed of multiple Virtual symbols.

[0081] An example of the operation of Repetition in symbol units will be described below.

[0082] [(1) Example of symbol-based repetition, virtual symbol and virtual slot configuration] In this embodiment, for example, "symbol-based repetition" is applied, in which one OFDM symbol is continuously and repeatedly transmitted.

[0083] In the following description, as an example, the number of repetitions in symbol units will be conveniently represented as "virtual symbol length".

[0084] Fig. 11 is a diagram showing an example of repetition in symbol units when virtualsymbolLength = 2. As shown in Fig. 11, the same OFDM symbol (each of OFDM symbols 0 to 13) is transmitted (in other words, arranged) consecutively.

[0085] Here, a time resource unit consisting of consecutive virtualsymbolLength OFDM symbols (e.g., normal symbols) is defined as a "virtual symbol". For example, in FIG. 11, one virtual symbol consists of two OFDM symbols. In the virtualsymbolLength OFDM symbols that make up the virtual symbol, a signal (e.g., PDSCH, PUSCH, or PUCCH) may be repeated.

[0086] Also, for example, in the case of a normal cyclic prefix, a time resource unit (in other words, a unit time interval) consisting of the same number of virtual symbols as the number of OFDM symbols (in other words, normal symbols) constituting a normal slot is defined as a "virtual slot." For example, in FIG. 11, one virtual slot consists of 14 virtual symbols. In other words, a virtual slot can be composed of 14×virtualsymbolLength OFDM symbols (28 OFDM symbols in FIG. 11).

[0087] In addition, in NR, for example, an extended cyclic prefix is ​​defined for 60 kHz SCS. In this case, for example, since the number of OFDM symbols included in a normal slot is 12, the number of virtual symbols included in a virtual slot may be set to 12.

[0088] In this way, by using symbol-based repetition, base station 100 and terminal 200 can perform in-phase synthesis of DMRS symbols and data symbols transmitted consecutively in multiple normal symbols constituting a virtual symbol. Therefore, symbol-based repetition can improve the reception SNR of the DMRS compared to slot-based or minislot-based repetition. Therefore, according to this embodiment, the channel estimation accuracy in base station 100 and terminal 200 can be improved.

[0089] Furthermore, in this embodiment, base station 100 and terminal 200 perform channel estimation by, for example, in-phase combining of DMRS symbols transmitted consecutively in a virtual symbol. Therefore, according to this embodiment, it is possible to suppress DMRS overhead and suppress deterioration of transmission efficiency, as compared to, for example, a method in which multiple DMRSs are arranged in each slot (e.g., equivalent to a normal slot) as shown in Fig. 6 or 7.

[0090] Furthermore, according to this embodiment, base station 100 and terminal 200 perform channel estimation by in-phase combining DMRS symbols transmitted consecutively within a virtual symbol, thereby making it possible to reduce processing delays in decoding and demodulation, as compared to inter-slot channel estimation using DMRSs arranged in multiple slots. Furthermore, this embodiment may be able to take advantage of the reduced delay in demodulation processing by front-load DMRS, which may be adopted in NR, for example.

[0091] [(2) Example of virtual symbol length configuration] Terminal 200 may receive, from base station 100, information regarding the number of Repetitions in symbol units or the number of OFDM symbols constituting a virtual symbol (eg, virtual symbol length), for example.

[0092] The virtual symbol length may be semi-statically notified from base station 100 to terminal 200 by, for example, a broadcast signal or a terminal-specific higher layer signal (e.g., an RRC signal), or may be dynamically notified from base station 100 to terminal 200 by dynamic signaling such as DCI.

[0093] Alternatively, for example, multiple candidates for virtualsymbolLength may be semi-statically notified from base station 100 to terminal 200 by an annunciation signal or a terminal-specific higher layer signal (e.g., an RRC signal), and one virtualsymbolLength value from among the multiple candidates may be dynamically notified from base station 100 to terminal 200 by dynamic signaling (or notification) such as DCI.

[0094] Furthermore, virtual symbol length may be set as in the following Options C-1 to C-4.

[0095] <option c-1> In Option C-1, for example, one value (in other words, one type) of virtualsymbolLength may be set for terminal 200. In other words, virtualsymbolLength may indicate one of a plurality of candidate symbol numbers that can be set for terminal 200.

[0096] For example, virtualsymbolLength may be set corresponding to the coverage extension level of terminal 200.

[0097] For example, virtualsymbolLength set in terminal 200 may be applied to multiple (for example, all) channels / signals. Note that "channel / signal" refers to a channel or a signal, or a combination of a channel and a signal.

[0098] The virtual symbol length may be applied to a channel / signal that terminal 200 may transmit / receive, such as an SS / PBCH Block (SSB) configured by a synchronization signal (SS) and a broadcast channel (e.g., a Physical Broadcast Channel (PBCH)), a Physical Random-Access Channel (PRACH), a PDCCH, a PDSCH, a PUCCH, a PUSCH, a CSI-Reference Signal (CSI-RS), or a sounding reference signal (e.g., a Sounding Reference Signal (SRS)). Note that the types of the channel / signal are not limited to these, and may be other channels / signals.

[0099] Alternatively, virtualsymbolLength set in terminal 200 may be applied to, for example, some channels / signals. In other words, among the channels / signals that terminal 200 may transmit and receive, there may be channels / signals to which symbol-based Repetition is applied and channels / signals to which symbol-based Repetition is not applied.

[0100] For example, the symbol-based repetition may be applied to the PUSCH, which is assumed to be highly likely to be set for coverage extension, and the symbol-based repetition may not be applied to other channels / signals different from the PUSCH. Alternatively, for example, the symbol-based repetition may not be applied to the SSB and PRACH, which are important for coexistence with existing terminals, and the symbol-based repetition may be applied to other channels / signals different from the SSB and PRACH.

[0101] Note that whether or not symbol-based Repetition is applied to channels / signals that can be transmitted / received by terminal 200 is not limited to the above-mentioned example.

[0102] < / option> <option c-2> In Option C-2, for example, virtualsymbolLength may be set for terminal 200 for each of the downlink and the uplink.

[0103] In NR, for example, coverage extension in the uplink is assumed compared to the downlink. Therefore, for example, the value of virtualsymbolLength for the uplink can be set to a value larger than the virtualsymbolLength for the downlink. This setting can improve, for example, the channel estimation accuracy in the uplink. Note that the relationship between the virtualsymbolLengths in the downlink and the uplink is not limited to the above example. For example, the virtualsymbolLengths in the uplink and the downlink may be the same value, or the virtualsymbolLength value for the downlink may be larger than the virtualsymbolLength value for the uplink.

[0104] In Option C-2, parameters such as "virtualsymbolLengthForDL" for the downlink and "virtualsymbolLengthForUL" for the uplink may be introduced.

[0105] In Option C-2, for example, virtualsymbolLength may be set for terminal 200 for either the downlink or the uplink.

[0106] < / option> <option c-3> In Option C-3, for example, virtual symbol length may be set for terminal 200 for each channel / signal used in communication.

[0107] In Option C-3, parameters such as "virtualsymbolLengthForPDCCH" for PDCCH, "virtualsymbolLengthForPDSCH" for PDSCH, "virtualsymbolLengthForPUCCH" for PUCCH, "virtualsymbolLengthForPUSCH" for PUSCH, "virtualsymbolLengthForCSI-RS" for CSI-RS, or "virtualsymbolLengthForSRS" for SRS may be introduced. Note that the types of channels / signals are not limited to these, and virtualsymbolLength may be set individually for other channels or signals.

[0108] For example, the expected number of repetitions may differ for each channel / signal. Therefore, in Option C-3, it is possible to set an appropriate number of repetitions for each channel / signal.

[0109] For example, different virtual symbol lengths may be set for data symbols and DMRS symbols in the PDCCH, PDSCH, PUCCH, and PUSCH.

[0110] Furthermore, the virtualsymbolLength is not limited to being set for each channel / signal individually, but may be set, for example, in units of multiple channels or signals (in other words, for each group of channels or signals).

[0111] < / option> <option c-4> In Option C-4, for example, multiple different virtualsymbolLength settings may be notified for each channel / signal. In other words, virtualsymbolLength may be set for each parameter setting (for example, configuration) for terminal 200.

[0112] For example, in PDCCH, a parameter for setting a control resource set (e.g., CORESET: Control Resource Set) may include virtualsymbolLength, and a value for virtualsymbolLength may be set for each CORESET. For example, in NR, operations of multiple transmission and reception points may be applied. In this case, since the distance from the terminal may differ between multiple transmission and reception points, the coverage extension level may differ for each of the multiple transmission and reception points. In this case, virtualsymbolLength may be included in the CORESET setting for each of the multiple transmission and reception points. This makes it possible to set different numbers of Repetitions for multiple transmission and reception points (in other words, different coverage extension levels), for example.

[0113] Also, for example, the virtual symbol length may be associated with a beam of the CORESET (for example, a Transmission Configuration Indicator (TCI) or an SRS Resource Indicator (SRI)).

[0114] Also, for example, a value of virtualsymbolLength may be set for each PUCCH format for PUCCH. For example, the number of symbols or the number of transmission bits may differ for each PUCCH format, and therefore the coverage extension level may differ. In this case, by setting virtualsymbolLength for each PUCCH format, it is possible to set different numbers of Repetitions for multiple PUCCH formats.

[0115] Also, for example, a value of virtualsymbolLength may be set for each SCS setting. For example, the larger the SCS, the wider the transmission bandwidth, and therefore the smaller the coverage. Therefore, the larger the SCS, the more Repetition counts can be set. In this case, different Repetition counts can be set for multiple SCS settings by setting virtualsymbolLength for each SCS setting.

[0116] [(3) Example of Virtual Symbol and Virtual Slot Configuration] When the virtual symbol length is set as in the above-mentioned Options C-1 to C-4, for example, base station 100 and terminal 200 may apply symbol-based Repetition to the target channel / signal and set virtual symbols and virtual slots.

[0117] As described above, a virtual symbol is a time resource unit consisting of, for example, virtualsymbolLength consecutive OFDM symbols (in other words, normal symbols). Also, in the case of normal CP, a virtual slot is a time resource unit consisting of, for example, 14 consecutive virtual symbols or 14×virtualsymbolLength consecutive OFDM symbols.

[0118] Here, the virtual symbol and virtual slot may be configured by either of the following two options, Option FS-1 and Option FS-2, based on the association with, for example, a normal symbol, a normal slot, a subframe, or a frame.

[0119] < / option> <option fs-1> In Option FS-1, the virtual slots may start, for example, from the beginning of the normal slots.

[0120] Fig. 12 is a diagram showing a configuration example when virtualsymbolLength = 2. In Option FS-1, as shown in Fig. 12, the position (e.g., the start position of the virtual slot) of the 0th normal symbol (e.g., normal symbol #0-0) included in the first virtual symbol (e.g., virtual symbol #0) constituting the virtual slot coincides with the position of the first symbol (e.g., normal symbol #0) constituting the normal slot.

[0121] Next, a setting example of virtual symbol length in Option FS-1 will be described.

[0122] (Option FS-1-1) In Option FS-1-1, the virtual symbol length (in other words, the number of symbols that make up the virtual symbol) may be set to a power of two.

[0123] Figure 13 shows the virtual symbol length of 2 (=2) for SCS=30kHz. 1 ), and virtualsymbolLength=4(=2 2 13 shows an example of the configuration of Option FS-1-1. As shown in FIG. 13, even if a different virtual symbol length value is set, for example, the virtual slot boundary can be aligned with the subframe boundary of the normal slot configuration.

[0124] In addition, in NR, for example, SCSs that are powers of 2 (for example, 30 kHz SCS, 60 kHz SCS, 120 kHz SCS, or 240 kHz SCS) are supported based on 15 kHz SCS. Therefore, for example, the configuration of virtual symbols and virtual slots corresponding to a (power of 2) times virtual symbol length can be a time resource unit similar to the configuration of normal symbols and normal slots with SCSs multiplied by 1 / (power of 2).

[0125] (Option FS-1-2) In Option FS-1-2, for example, in the case of Normal CP, the virtual symbol length (in other words, the number of symbols constituting the virtual symbol) may be set to any one of 2, 7, 14, and an integer multiple of 14.

[0126] Fig. 14 is a diagram showing an example of the configuration when SCS = 30 kHz and virtual symbol Length = 2 and virtual symbol Length = 7. As shown in Fig. 14, in Option FS-1-2, for example, even if different virtual symbol Length values ​​are set, it is possible to make the virtual slot boundary coincide with the slot boundary of the normal slot configuration.

[0127] For example, when a terminal to which symbol-based Repetition is not applied exists within a cell (in other words, a terminal using normal symbols and normal slots), there is an advantage that this terminal and terminal 200 can easily coexist in scheduling, etc., by making the virtual slot boundary coincident with the normal slot boundary.

[0128] When using an extended CP, it is possible to obtain the same effect as in the case of a normal CP by setting the value that can be set for virtualsymbolLength to, for example, any of 2, 6, 12, and an integer multiple of 12. In other words, in Option FS-1-2, virtualsymbolLength (for example, the number of normal symbols that make up a virtual symbol) may be set based on the number of normal symbols that make up a normal slot.

[0129] (Option FS-1-3) In Option FS-1-2, when virtual slot boundaries and normal slot boundaries are made to coincide with each other, the granularity of the value that can be set for virtualsymbolLength is 2, 7, 14, or an integer multiple of 14, so it may not be possible to flexibly accommodate the coverage extension level.

[0130] Therefore, in Option FS-1-3, for example, the number of normal symbols (for example, virtual symbol length) included in the virtual symbols constituting a virtual slot may be uneven between the virtual symbols. Also, in Option FS-1-3, the virtual slot boundary and the normal slot boundary coincide with each other.

[0131] FIG. 15 is a diagram showing an example in which a virtual slot is configured by virtual symbols with virtualsymbolLength=3 and virtualsymbolLength=4 when SCS=30 kHz.

[0132] 15, for example, a virtual symbol composed of three OFDM symbols and a virtual symbol composed of four OFDM symbols are included. In other words, the number of normal symbols constituting at least two virtual symbols included in a virtual slot (in other words, virtual symbol length) is different from each other.

[0133] Also, in Fig. 15, for example, the slot boundaries of the normal slot configuration coincide with the virtual symbol boundaries. In other words, in Fig. 15, the interval of each virtual symbol does not straddle a normal slot boundary.

[0134] Option FS-1-3 has the advantage that, like Option FS-1-2, even if a terminal to which symbol-based repetition is not applied and a terminal to which symbol-based repetition is applied exist in a cell, the virtual slot boundary and the normal slot boundary are aligned, making it easier for them to coexist in scheduling, etc. Furthermore, compared to Option FS-1-2, Option FS-1-3 can realize coverage extension with finer granularity (for example, granularity different from 2, 7, 14, and integer multiples of 14).

[0135] In Option FS-1-3, for example, the definition of a time resource unit consisting of 14 virtual symbols (in the case of normal CP), which is the same number as the number of OFDM symbols included in the normal slot configuration, as explained in "(1) Configuration examples of symbol-based repetition, virtual symbols, and virtual slots" as a virtual slot does not need to be applied. In other words, the number of virtual symbols included in a virtual slot may be different from the number of OFDM symbols included in a normal slot.

[0136] (Option FS-1-4) In Option FS-1-4, an upper limit may be set for the value that can be set for virtualsymbolLength. For example, the upper limit for the number of normal symbols that make up a virtual symbol may be less than the number of normal symbols that make up a normal slot. For example, in the case of a normal CP, the upper limit may be a value less than 14, such as 7 or 4.

[0137] In NR, for example, base station 100 can flexibly set the type of slot or the type of symbol in a slot (for example, downlink symbol, uplink symbol, or flexible symbol). For example, when applying symbol-based Repetition, it is desirable to set a common symbol type in a time interval corresponding to the number of normal symbols set in virtualsymbolLength.

[0138] For example, the larger the value of virtualsymbolLength, the greater the number of normal symbols (e.g., the number of consecutive symbols of the same symbol type) that compose a virtual symbol, and the greater the possibility that it will be difficult to flexibly respond to traffic conditions within a cell. Therefore, for example, the smaller the upper limit value of virtualsymbolLength to which symbol-based Repetition is applied, the easier it is to realize a flexible TDD pattern.

[0139] A method of compensating for the coverage expansion effect when the number of repetitions applicable to the symbol-based repetition is reduced will be described later.

[0140] This concludes the explanation of Option FS-1.

[0141] Any of Options FS-1-1 to FS-1-4 may be combined. For example, Option FS-1-1 and Option FS-1-4 may be combined to set the value that can be set to virtual symbolLength to 1, 2, or 4. In NR, a frame of 10 ms is adopted in addition to time resource units called slots and subframes. For example, when virtual symbolLength=2, the virtual slot boundary can be made to coincide with the frame boundary of the normal slot configuration, which is advantageous in that the operation of the System Frame Number (SFN) can be made easier. Also, for example, when virtual symbolLength=4, the virtual slot boundary can be made to coincide with the frame boundary of the normal slot configuration every 20 ms. In NR operation, for example, the transmission interval of the SSB used for initial access is assumed to be 20 ms, so that it is highly compatible with the operation of the SSB.

[0142] < / option><option fs-2> In Option FS-2, a virtual slot may start, for example, at any symbol position of a normal slot.

[0143] Fig. 16 is a diagram showing a configuration example of virtual symbol length=2. In Option FS-2, as shown in Fig. 16, the virtual slot starts from the fifth symbol (normal symbol #5) of the normal slot. In other words, the position of the 0th normal symbol (normal symbol #0-0) included in the first virtual symbol #0 constituting the virtual slot (in other words, the start position of the virtual slot) coincides with the position of the fifth symbol (normal symbol #5) in the normal slot.

[0144] According to Option FS-2, for example, in symbol-based repetition, resource allocation can be performed more flexibly compared to resource allocation in the time domain, which will be described later.

[0145] (4) Resource Allocation Time domain resource allocation for the PDSCH received by terminal 200 and the PUSCH and PUCCH transmitted by terminal 200 may be determined (in other words, specified) based on, for example, a virtual symbol or a virtual slot.

[0146] An example of determining a time domain resource will be described below.

[0147] < / option> <option ra-1> In Option RA-1, for example, base station 100 and terminal 200 may determine (in other words, specify) time domain resources for communication based on virtual symbols and virtual slots. In other words, in Option RA-1, for example, normal slots and normal symbols do not need to be used to specify time domain resources.

[0148] As an example, Option RA-1 may be applied to Option FS-1 described above.

[0149] An example of applying Option RA-1 to PDSCH, PUSCH, and PUCCH will be described below.

[0150] (Option RA-1:PDSCH) Base station 100 may, for example, allocate resources for a PDSCH and transmit DCI for the PDSCH to which resources have been allocated, on a PDCCH, to terminal 200. Terminal 200, for example, receives and decodes the PDCCH, and demodulates and decodes the PDSCH based on control information included in the DCI.

[0151] Here, the control information included in the DCI may include, for example, information on the time domain resource to which the PDSCH is allocated (for example, TDRA information).

[0152] The information on the time domain resource may include, for example, information on the timing of how many virtual slots after the virtual slot in which terminal 200 receives the PDSCH that the PDSCH will be received (for example, referred to as “K0” or virtual slot offset), the virtual symbol position of the head of the PDSCH in the virtual slot (for example, “S PDSCH " or starting virtual symbol), and the number of virtual symbols to which the PDSCH is assigned (for example, "L PDSCH " or Virtual symbol length) may be included.

[0153] The information on the time domain resource is stored in the TDRA table (K0, S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S11, S12, S13, S14, S15, S16, S17, S18, S20, S21, S22, S23, S24, S25, S30, S31, S32, S33, S41, S PDSCH , L PDSCH , and candidates for combinations of PDSCH mapping types) may be configured semi-statically, and the combination to be used may be configured from the TDRA table by dynamic notification such as DCI.

[0154] In addition, the virtual symbol position S PDSCH and the number of virtual symbols L PDSCH may be set in terminal 200 by a value associated with a combination of a symbol position and a symbol number (eg, SLIV: Start and Length Indicator Value).

[0155] For example, a virtual slot in which terminal 200 receives the PDSCH may be specified according to the following equation (1).

number

[0156] Here, n indicates a virtual slot in which terminal 200 receives DCI (or PDCCH) corresponding to the PDSCH allocation. μPDSCH indicates the SCS of the carrier or Bandwidth Part (BWP) receiving the PDSCH, and 2 μPDCCH indicates the SCS of a carrier or BWP receiving DCI (or PDCCH). Moreover, virtualsymbolLengthForPDCCH indicates a virtual symbolLength applied to a PDCCH including DCI corresponding to a PDSCH allocation, and virtualsymbolLengthForPDSCH indicates a virtual symbolLength applied to a PDSCH received by terminal 200. Moreover, a floor function for a value x as shown in equation (1) may be expressed as "floor(x)".

[0157] For example, terminal 200 may specify a virtual slot in which to receive the PDSCH according to equation (1). In addition, terminal 200 may specify, for example, S PDSCH The terminal 200 may specify a virtual symbol (in other words, a start position) at which to start receiving the PDSCH based on, for example, L PDSCH Based on this, the number of virtual symbols for receiving the PDSCH may be determined.

[0158] 17 is a diagram showing an example of time domain resource allocation for PDSCH. In FIG. 17, virtualsymbolLengthForPDCCH=1 for PDCCH, virtualsymbolLengthForPDSCH=2 for PDSCH, K0=0, S PDSCH =1, L PDSCH =13.

[0159] In FIG. 17, for example, the PDSCH is S in a virtual slot K0=0 slots after the virtual slot in which terminal 200 receives the PDCCH (in other words, the same virtual slot). PDSCH = Virtual symbol no. 1 to L PDSCH = 13 virtual symbols (for example, virtual symbols #1 to #13).

[0160] According to Option RA-1, for example, a virtual symbol length is set for terminal 200, and a virtual symbol and a virtual slot are configured, so that the time domain resource for the symbol-by-symbol Repetition can be specified by using notification of the time domain resource for the PDSCH similar to the normal slot configuration.

[0161] As described above, the time domain resource for the PDSCH is specified using the virtual symbol and the virtual slot. Meanwhile, the signal (for example, PDSCH) actually received by the terminal 200 is a signal in units of normal symbols, and the terminal 200 receives, for example, virtualsymbolLengthForPDSCH normal symbols in the time interval of the virtual symbol. For example, the base station 100 may generate a complex symbol group of the number of virtual symbols according to the PDSCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLengthForPDSCH normal symbols included in one virtual symbol. Furthermore, the terminal 200 may assume, for example, that one complex symbol group is duplicated and mapped to a normal symbol included in one virtual symbol in the base station 100. Furthermore, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0162] (Option RA-1:PUSCH) Terminal 200 may transmit the PUSCH in accordance with, for example, at least one of a resource allocation indicated by DCI in a PDCCH from base station 100 and a resource allocation preset by a higher layer signal (for example, an RRC signal).

[0163] Here, the control information included in the DCI or the control information set in advance by a higher layer signal may include, for example, information on the time domain resource for transmitting the PUSCH (for example, TDRA information).

[0164] The information on the time domain resource may include, for example, information on the timing of how many virtual slots after the virtual slot in which terminal 200 receives the PDCCH to transmit the PUSCH (for example, referred to as “K2” or virtual slot offset), the virtual symbol position of the head of the PUSCH in the virtual slot (for example, “S PUSCH " or starting virtual symbol), and the number of virtual symbols to transmit the PUSCH (for example, "L PUSCH " or Virtual symbol length) may be included.

[0165] The information on the time domain resource is stored in the TDRA table (K2, S PUSCH , L PUSCH , and candidate combinations of PUSCH mapping types) may be configured semi-statically, and the combination to be used may be configured from the TDRA table by dynamic notification such as DCI or pre-configuration by higher layer signaling (e.g., RRC signaling).

[0166] In addition, the virtual symbol position S PUSCH and the number of virtual symbols L PUSCH may be set in terminal 200 by, for example, a value associated with a combination of a virtual position and a virtual symbol number (for example, SLIV).

[0167] For example, a virtual slot in which terminal 200 transmits a PUSCH may be specified according to the following equation (2).

number

[0168] Here, n indicates a virtual slot in which terminal 200 receives DCI (or PDCCH) corresponding to PUSCH allocation. μPUSCH indicates the SCS of the carrier or BWP transmitting the PUSCH, and 2 μPDCCH indicates the SCS of a carrier or BWP receiving DCI (or PDCCH). Also, virtualsymbolLengthForPDCCH indicates a virtual symbolLength applied to a PDCCH including DCI corresponding to a PUSCH allocation, and virtualsymbolLengthForPUSCH indicates a virtual symbolLength applied to a PUSCH transmitted by terminal 200.

[0169] For example, terminal 200 may specify a virtual slot in which to transmit the PUSCH according to equation (2). In addition, terminal 200 may specify, for example, S PUSCH The terminal 200 may specify a virtual symbol (in other words, a start position) at which to start transmitting the PUSCH based on, for example, L PUSCH The number of virtual symbols for transmitting the PUSCH may be determined based on the above.

[0170] FIG. 18 is a diagram showing an example of time domain resource allocation for PUSCH. In FIG. 18, virtualsymbolLengthForPDCCH=1 for PDCCH, virtualsymbolLengthForPUSCH=2 for PUSCH, K2=1, S PUSCH =0, L PUSCH =14.

[0171] In FIG. 18, for example, the PUSCH is S in a virtual slot K2=1 slot after the virtual slot in which terminal 200 receives the PDCCH. PUSCH =0th Virtual Symbol to L PUSCH = 14 symbols (for example, virtual symbols #0 to #13).

[0172] According to Option RA-1, for example, a virtual symbol length is set for terminal 200, and a virtual symbol and a virtual slot are configured, so that a time domain resource for Repetition on a symbol-by-symbol basis can be specified by reporting a time domain resource for PUSCH similar to the normal slot configuration.

[0173] Note that the time domain resource for PUSCH is specified using the virtual symbol and the virtual slot as described above. On the other hand, the signal (for example, PUSCH) actually transmitted by the terminal 200 is a signal in units of normal symbols, and the terminal 200 transmits, for example, virtualsymbolLengthForPUSCH normal symbols in the time interval of the virtual symbol. For example, the terminal 200 may generate a complex symbol group of the number of virtual symbols according to the PUSCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLengthForPUSCH normal symbols included in one virtual symbol. Also, the base station 100 may assume that, for example, one complex symbol group is duplicated and mapped to a normal symbol included in one virtual symbol in the terminal 200. Also, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0174] (Option RA-1:PUCCH) Terminal 200 may, for example, feed back, in the PUCCH, an ACK / NACK indicating success or failure of decoding of the PDSCH. Terminal 200 may also transmit other UCI such as CSI or SR to base station 100 using the PUCCH.

[0175] Furthermore, when transmitting an ACK / NACK for a PDSCH allocated by DCI, terminal 200 may transmit a PUCCH according to resource allocation indicated by DCI in a PDCCH from base station 100, for example.

[0176] Here, the control information included in the DCI may include, for example, information regarding a PUCCH resource. The PUCCH resource may be configured by, for example, a plurality of parameters.

[0177] Among the PUCCH resources, information regarding time domain resources may include, for example, information regarding the virtual symbol position at the beginning of the PUCCH in a virtual slot (e.g., referred to as "startingSymbolIndex" or starting virtual symbol) and the number of virtual symbols for transmitting the PUCCH (e.g., referred to as "nrofSymbols" or virtual symbol length).

[0178] Furthermore, the control information included in the DCI may include, for example, information regarding the timing of transmitting the PUCCH, such as how many virtual slots after the virtual slot in which terminal 200 receives the PDSCH (for example, the number of virtual slots "k").

[0179] For CSI and SR, PUCCH resources may be specified by, for example, a higher layer signal (eg, an RRC signal) from base station 100 to terminal 200.

[0180] For example, the virtual slot in which terminal 200 transmits the PUCCH may be specified according to the following equation (3).

number

[0181] Here, n indicates a virtual slot in which terminal 200 receives a PDSCH. For example, k=0 may correspond to the last virtual slot that overlaps in time with the virtual slot in which the PDSCH is received, among the virtual slots applied to the PUCCH.

[0182] For example, terminal 200 may specify a virtual slot for transmitting PUCCH according to equation (3). Terminal 200 may also specify a virtual symbol at which to start transmitting PUCCH (in other words, a starting position) in the specified virtual slot, for example, based on startingSymbolIndex. Terminal 200 may also specify the number of virtual symbols for transmitting PUCCH, for example, based on nrofSymbols.

[0183] Fig. 19 is a diagram showing an example of time domain resource allocation for PUCCH. In Fig. 19, virtualsymbolLengthForPDCCH=virtualsymbolLengthForPDSCH=1 for each of PDCCH and PDSCH, and virtualsymbolLengthForPUCCH=2, k=1, startingSymbolIndex=7, and nrofSymbol=7 for PUCCH.

[0184] In FIG. 19, for example, PUCCH is transmitted from virtual symbol with startingSymbolIndex=7 in a virtual slot k=1 slot after the virtual slot in which terminal 200 received PDSCH to nrofSymbol=7 symbols (for example, virtual symbols #7 to #13).

[0185] According to Option RA-1, for example, virtual symbol length is set for terminal 200, and virtual symbols and virtual slots are configured, so that time domain resources for symbol-by-symbol Repetition can be specified using PUCCH resource notification similar to the normal slot configuration.

[0186] As described above, the time domain resource for PUCCH is specified using the virtual symbol and the virtual slot. Meanwhile, the signal (for example, PUCCH) actually transmitted by the terminal 200 is a signal in units of normal symbols, and the terminal 200 transmits, for example, virtualsymbolLengthForPUCCH normal symbols in the time interval of the virtual symbol. For example, the terminal 200 may generate a complex symbol group of the number of virtual symbols according to the PUCCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLengthForPUCCH normal symbols included in one virtual symbol. Also, the base station 100 may assume, for example, that one complex symbol group is duplicated and mapped to a normal symbol included in one virtual symbol in the terminal 200. Also, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0187] < / option> <option ra-2> In Option RA-2, for example, the base station 100 and the terminal 200 may determine (in other words, specify) time domain resources for communication based on virtual symbols and virtual slots. Also, in Option RA-2, the base station 100 and the terminal 200 may use at least one of normal symbols and normal slots to allocate the leading symbol position of the time domain resources.

[0188] As an example, Option RA-2 may be applied to Option FS-2 described above.

[0189] An example of applying Option RA-2 to PDSCH, PUSCH, and PUCCH will be described below.

[0190] (Option RA-2:PDSCH) Base station 100 may, for example, allocate resources for a PDSCH and transmit DCI for the PDSCH to which resources have been allocated, on a PDCCH, to terminal 200. Terminal 200, for example, receives and decodes the PDCCH, and demodulates and decodes the PDSCH based on control information included in the DCI.

[0191] Here, the control information included in the DCI may include, for example, information on the time domain resource to which the PDSCH is allocated (for example, TDRA information).

[0192] The information regarding the time domain resource includes, for example, information regarding the timing of how many normal slots after the normal slot in which terminal 200 receives the PDCCH when it starts receiving the PDSCH (referred to as "K0" or normal slot offset), the normal symbol position at the beginning of the PDSCH in the normal slot (for example, "S PDSCH " or the start normal symbol), and the number of virtual symbols to which the PDSCH is assigned (for example, "L PDSCH " or Virtual symbol length) may be included.

[0193] The information on the time domain resource is stored in the TDRA table (K0, S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S11, S12, S13, S14, S15, S16, S17, S18, S20, S21, S22, S23, S24, S25, S30, S31, S32, S33, S41, S PDSCH , L PDSCH , and candidates for combinations of PDSCH mapping types) may be configured semi-statically, and the combination to be used may be configured from the TDRA table by dynamic notification such as DCI.

[0194] In addition, the normal symbol position S PDSCH and the number of virtual symbols L PDSCH may be set in terminal 200 by a value (eg, SLIV) associated with a combination of a symbol position and a symbol number, for example.

[0195] For example, the normal slot in which terminal 200 starts receiving the PDSCH may be specified according to the following equation (4).

number

[0196] Here, n indicates a normal slot in which terminal 200 receives DCI (or PDCCH) corresponding to the PDSCH allocation. μPDSCH indicates the SCS of the carrier or BWP receiving the PDSCH, and 2 μPDCCH indicates the SCS of the carrier or BWP that receives DCI (or PDCCH).

[0197] For example, terminal 200 may specify a normal slot in which to start receiving the PDSCH according to equation (4). In addition, terminal 200 may specify, for example, S PDSCH The terminal 200 may specify a normal symbol (in other words, a start position) at which to start receiving the PDSCH based on, for example, L PDSCH Based on this, the number of virtual symbols for receiving the PDSCH may be determined.

[0198] FIG. 20 is a diagram showing an example of time domain resource allocation for PDSCH. In FIG. 20, virtualsymbolLengthForPDCCH=1 for PDCCH, virtualsymbolLengthForPDSCH=2 for PDSCH, K0=0, S PDSCH =1, L PDSCH =13.

[0199] In the example of FIG. 20, terminal 200 receives S in a normal slot K0=0 slots after the normal slot in which terminal 200 receives the PDCCH (in other words, the same normal slot). PDSCH = From the symbol position corresponding to the first normal symbol (Normal symbol #1) PDSCH In the 13 virtual symbols (eg, virtual symbols #0 to #12), a PDSCH to which symbol-by-symbol Repetition is applied is received.

[0200] According to Option RA-2, for example, a virtual symbol length is set for terminal 200, and a virtual symbol and a virtual slot are configured, so that a time domain resource for symbol-by-symbol Repetition can be specified by using notification of a time domain resource for PDSCH similar to the normal slot configuration.

[0201] In addition, according to Option RA-2, for example, in the allocation of time domain resources, parameters in normal symbol units and normal slot units (e.g., K0 and S PDSCH ), terminal 200 can receive PDSCH, for example, from any normal symbol position in a normal slot (for example, any normal symbol position including the first symbol). For example, in Option RA-2, it is possible to set the PDSCH reception start position with finer granularity (for example, one normal symbol) than the granularity of a virtual symbol (two normal symbols in FIG. 20). Therefore, in Option RA-2, it is possible to improve the flexibility of PDSCH resource allocation compared to, for example, Option RA-1.

[0202] Note that the time domain resource for the PDSCH is specified using the virtual symbol and the virtual slot as described above. Meanwhile, the signal (for example, PDSCH) actually received by the terminal 200 is a signal in units of normal symbols, and the terminal 200 receives, for example, virtualsymbolLengtForPDSCH normal symbols in the time interval of the virtual symbol. For example, the base station 100 may generate a complex symbol group of the number of virtual symbols according to the PDSCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLengthForPDSCH normal symbols included in one virtual symbol. Furthermore, the terminal 200 may assume that, for example, one complex symbol group is duplicated and mapped to a normal symbol included in one virtual symbol in the base station 100. Furthermore, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0203] (Option RA-2:PUSCH) Terminal 200 may transmit the PUSCH in accordance with, for example, at least one of a resource allocation indicated by DCI in a PDCCH from base station 100 and a resource allocation preset by a higher layer signal (for example, an RRC signal).

[0204] Here, the control information included in the DCI or the control information set in advance by a higher layer signal may include, for example, information on the time domain resource for transmitting the PUSCH (for example, TDRA information).

[0205] The information regarding the time domain resource includes, for example, information regarding the timing of how many normal slots after the normal slot in which terminal 200 receives the PDCCH to transmit the PUSCH (for example, referred to as “K2” or normal slot offset), the normal symbol position at the beginning of the PUSCH in the normal slot (for example, “S PUSCH " or the start normal symbol), and the number of virtual symbols to transmit the PUSCH (for example, "L PUSCH " or Virtual symbol length) may be included.

[0206] The information on the time domain resource is stored in the TDRA table (K2, S PUSCH , L PUSCH , and candidate combinations of PUSCH mapping types) may be configured semi-statically, and the combination to be used may be configured from the TDRA table by dynamic notification such as DCI or pre-configuration by higher layer signaling (e.g., RRC signaling).

[0207] In addition, the virtual symbol position S PUSCH and the number of virtual symbols L PUSCH may be set in terminal 200 by, for example, a value associated with a combination of a virtual position and a virtual symbol number (for example, SLIV).

[0208] For example, a normal slot in which terminal 200 transmits a PUSCH may be specified according to the following equation (5).

number

[0209] Here, n indicates a normal slot in which terminal 200 receives DCI (or PDCCH) corresponding to PUSCH allocation. μPUSCH indicates the SCS of the carrier or BWP transmitting the PUSCH, and 2 μPDCCH indicates the SCS of the carrier or BWP that receives DCI (or PDCCH).

[0210] For example, terminal 200 may specify a normal slot in which to transmit a PUSCH according to equation (5). In addition, terminal 200 may specify, for example, S PUSCH The terminal 200 may specify a normal symbol (in other words, a start position) at which to start transmitting the PUSCH based on, for example, L PUSCH The number of virtual symbols for transmitting the PUSCH may be determined based on the above.

[0211] According to Option RA-2, for example, a virtual symbol length is set for terminal 200, and a virtual symbol and a virtual slot are configured, so that a time domain resource for Repetition on a symbol-by-symbol basis can be specified by reporting a time domain resource for PUSCH similar to the normal slot configuration.

[0212] In addition, according to Option RA-2, for example, in the allocation of time domain resources, parameters in normal symbol units and normal slot units (e.g., K2 and S PUSCH ), terminal 200 can transmit the PUSCH from, for example, any normal symbol position in a normal slot (for example, any normal symbol position including the first symbol). For example, in Option RA-2, the transmission start position of the PUSCH can be set with finer granularity than the granularity of virtual symbols. Therefore, in Option RA-2, it is possible to improve the flexibility of PUSCH resource allocation compared to, for example, Option RA-1.

[0213] Note that the time domain resource for PUSCH is specified using the virtual symbol and the virtual slot as described above. On the other hand, the signal (for example, PUSCH) actually transmitted by the terminal 200 is a signal in units of normal symbols, and the terminal 200 transmits, for example, virtualsymbolLengthForPUSCH normal symbols in the time interval of the virtual symbol. For example, the terminal 200 may generate a complex symbol group of the number of virtual symbols according to the PUSCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLengthForPUSCH normal symbols included in one virtual symbol. Also, the base station 100 may assume that, for example, one complex symbol group is duplicated and mapped to a normal symbol included in one virtual symbol in the terminal 200. Also, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0214] (Option RA-2:PUCCH) Terminal 200 may, for example, feed back, in the PUCCH, an ACK / NACK indicating success or failure of decoding of the PDSCH. Terminal 200 may also transmit other UCI such as CSI or SR to base station 100 using the PUCCH.

[0215] Furthermore, when transmitting an ACK / NACK for a PDSCH allocated by DCI, terminal 200 may transmit a PUCCH according to resource allocation indicated by DCI in a PDCCH from base station 100, for example.

[0216] Here, the control information included in the DCI may include, for example, information regarding a PUCCH resource. The PUCCH resource may be configured by, for example, a plurality of parameters.

[0217] Among the PUCCH resources, information regarding time domain resources may include, for example, information regarding the normal symbol position at the beginning of the PUCCH in a normal slot (e.g., referred to as "startingSymbolIndex" or starting normal symbol) and the number of virtual symbols for transmitting the PUCCH (e.g., referred to as "nrofSymbols" or virtual symbol length).

[0218] Furthermore, the control information included in the DCI may include, for example, information regarding the timing, such as how many normal slots after the normal slot in which terminal 200 receives the PDSCH, the transmission of the PUCCH is started (for example, the number of normal slots “k”).

[0219] For CSI and SR, PUCCH resources may be specified by, for example, a higher layer signal (eg, an RRC signal) from base station 100 to terminal 200.

[0220] For example, a normal slot in which terminal 200 transmits a PUCCH may be specified according to the following equation (6).

number

[0221] Here, n indicates a normal slot in which terminal 200 receives a PDSCH. For example, k=0 may correspond to the last normal slot that overlaps in time with the normal slot in which a PDSCH is received, among normal slots applied to a PUCCH.

[0222] For example, terminal 200 may specify a normal slot in which to transmit PUCCH according to equation (6). Terminal 200 may also specify a normal symbol (in other words, a starting position) in which to start transmitting PUCCH, based on startingSymbolIndex, in the specified normal slot. Terminal 200 may also specify the number of virtual symbols in which to transmit PUCCH, based on nrofSymbols, for example.

[0223] According to Option RA-2, for example, a virtual symbol length is set for terminal 200, and a virtual symbol and a virtual slot are configured, so that a time domain resource for Repetition on a symbol-by-symbol basis can be specified by reporting a time domain resource for PUSCH similar to the normal slot configuration.

[0224] Also, according to Option RA-2, for example, by using parameters (e.g., k and startingSymbolIndex) for normal symbol units and normal slot units in time domain resource allocation, terminal 200 can transmit PUCCH from, for example, any normal symbol position in a normal slot (e.g., any normal symbol position including the leading symbol). For example, in Option RA-2, it is possible to set the PUCCH transmission start position with finer granularity than the granularity of virtual symbols. Therefore, in Option RA-2, it is possible to improve the flexibility of PUCCH resource allocation compared to, for example, Option RA-1.

[0225] As described above, the time domain resource for PUCCH is specified using the virtual symbol and the virtual slot. Meanwhile, the signal (for example, PUCCH) actually transmitted by the terminal 200 is a signal in units of normal symbols, and the terminal 200 transmits, for example, virtualsymbolLength normal symbols in the time interval of the virtual symbol. For example, the terminal 200 may generate a complex symbol group of the number of virtual symbols according to the PUCCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLength normal symbols included in one virtual symbol. Furthermore, the base station 100 may assume, for example, that one complex symbol group is duplicated and mapped to the normal symbol included in one virtual symbol in the terminal 200. Furthermore, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0226] < / option> <option ra-3> In Option RA-3, for example, base station 100 and terminal 200 may determine (in other words, specify) time domain resources for communication based on virtual symbols and virtual slots. Also, in Option RA-3, for example, base station 100 and terminal 200 may introduce an offset related to normal symbols (for example, an offset in normal symbol units) when specifying time domain resources.

[0227] As an example, Option RA-3 may be applied to either Option FS-1 or Option FS-2 described above.

[0228] An example of applying Option RA-3 to PDSCH, PUSCH, and PUCCH will be described below.

[0229] (Option RA-3:PDSCH) Base station 100 may, for example, allocate resources for a PDSCH and transmit DCI for the PDSCH to which resources have been allocated, on a PDCCH, to terminal 200. Terminal 200, for example, receives and decodes the PDCCH, and demodulates and decodes the PDSCH based on control information included in the DCI.

[0230] Here, the control information included in the DCI may include, for example, information on the time domain resource to which the PDSCH is allocated (for example, TDRA information).

[0231] The information on the time domain resource may include, for example, information on the timing of how many virtual slots after the virtual slot in which terminal 200 receives the PDSCH that the PDSCH will be received (referred to as “K0” or a virtual slot offset), the virtual symbol position of the head of the PDSCH in the virtual slot (for example, “S PDSCH " or starting virtual symbol), and the number of virtual symbols to which the PDSCH is assigned (for example, "L PDSCH " or Virtual symbol length) may be included.

[0232] The information on the time domain resource is stored in the TDRA table (K0, S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S11, S12, S13, S14, S15, S16, S17, S18, S20, S21, S22, S23, S24, S25, S30, S31, S32, S33, S41, S PDSCH , L PDSCH , and candidates for combinations of PDSCH mapping types) may be configured semi-statically, and the combination to be used may be configured from the TDRA table by dynamic notification such as DCI.

[0233] In addition, the virtual symbol position S PDSCH and the number of virtual symbols L PDSCH may be set in terminal 200 by a value associated with a combination of a symbol position and a symbol number (eg, SLIV: Start and Length Indicator Value).

[0234] In Option RA-3, the information on the time domain resource may include, for example, an offset in normal symbol units. The offset may be notified from base station 100 to terminal 200 by at least one of a terminal-specific higher layer signal (for example, an RRC signal) and DCI, separately from the TDRA information. Alternatively, the offset may be included in the TDRA table and notified (in other words, set).

[0235] For example, a virtual slot in which terminal 200 receives the PDSCH may be specified according to the following equation (7).

number

[0236] Here, n indicates a virtual slot in which terminal 200 receives DCI (for example, PDCCH) corresponding to the PDSCH allocation. μPDSCH indicates the SCS of the carrier or BWP receiving the PDSCH, and 2 μPDCCH indicates the SCS of a carrier or BWP receiving DCI (or PDCCH). Also, virtualsymbolLengthForPDCCH indicates a virtual symbolLength applied to a PDCCH including DCI corresponding to a PDSCH allocation, and virtualsymbolLengthForPDSCH indicates a virtual symbolLength applied to a PDSCH received by terminal 200.

[0237] For example, terminal 200 may specify a virtual slot in which to receive the PDSCH according to equation (7). In addition, terminal 200 may specify, for example, S PDSCH The terminal 200 may specify a virtual symbol (in other words, a start position) at which to start receiving the PDSCH based on, for example, L PDSCH Based on this, the number of virtual symbols for receiving the PDSCH may be determined.

[0238] Furthermore, in Option RA-3, terminal 200 identifies a time domain resource for receiving a PDSCH by, for example, the method described above, and then shifts the time domain resource for receiving a PDSCH by the offset based on the offset in normal symbol units.

[0239] Fig. 21 is a diagram showing an example of time domain resource allocation for PDSCH. In Fig. 21, virtualsymbolLengthForPDCCH=1 for PDCCH, virtualsymbolLengthForPDSCH=2 for PDSCH, K0=0, S PDSCH =1, L PDSCH = 13, offset in normal symbol units = 1 symbol.

[0240] In FIG. 21, for example, the PDSCH is S in a virtual slot K0=0 slots after the virtual slot in which terminal 200 receives the PDCCH (in other words, the same virtual slot). PDSCH = Virtual symbol no. 1 to L PDSCH = 13 virtual symbols (for example, virtual symbols #1 to #13). Also, as shown in Fig. 21, virtual symbols #1 to #13 to which the PDSCH is allocated are shifted by an offset = 1 normal symbol.

[0241] According to Option RA-3, for example, a virtual symbol length is set for terminal 200, and a virtual symbol and a virtual slot are configured, so that a time domain resource for Repetition on a symbol-by-symbol basis can be specified by using notification of a time domain resource for PDSCH similar to the normal slot configuration.

[0242] Also, according to Option RA-3, for example, in time domain resource allocation, by applying an offset in normal symbol units, terminal 200 becomes able to receive PDSCH, for example, from any normal symbol position in a normal slot (for example, any normal symbol position including the leading symbol). For example, in Option RA-3, it becomes possible to set the reception start position of PDSCH with finer granularity (for example, one normal symbol) than the granularity of virtual symbols (two normal symbols in FIG. 21). Therefore, in Option RA-3, it is possible to improve the flexibility of PDSCH resource allocation compared to, for example, Option RA-1.

[0243] Note that the time domain resource for the PDSCH is specified using the virtual symbol and the virtual slot as described above. Meanwhile, the signal (for example, PDSCH) actually received by the terminal 200 is a signal in units of normal symbols, and the terminal 200 receives, for example, virtualsymbolLengthForPDSCH normal symbols in the time interval of the virtual symbol. For example, the base station 100 may generate a complex symbol group of the number of virtual symbols according to the PDSCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLengthForPDSCH normal symbols included in one virtual symbol. Furthermore, the terminal 200 may assume that, for example, one complex symbol group is duplicated and mapped to a normal symbol included in one virtual symbol in the base station 100. Furthermore, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0244] Also, the example shown in FIG.21 is similar to an example in which, for example, the configuration of Option FS-2 is applied. On the other hand, Option RA-3 may be applied to, for example, the configuration of Option FS-1. When Option RA-3 is applied to Option FS-1, terminal 200 may receive, for example, a part of normal symbols included in virtual symbols.

[0245] (Option RA-3:PUSCH) Terminal 200 may transmit the PUSCH in accordance with, for example, at least one of a resource allocation indicated by DCI in a PDCCH from base station 100 and a resource allocation preset by a higher layer signal (for example, an RRC signal).

[0246] Here, the control information included in the DCI or the control information set in advance by a higher layer signal may include, for example, information on the time domain resource for transmitting the PUSCH (for example, TDRA information).

[0247] The information on the time domain resource may include, for example, information on the timing of how many virtual slots after the virtual slot in which terminal 200 receives the PDCCH to transmit the PUSCH (for example, referred to as “K2” or virtual slot offset), the virtual symbol position of the head of the PUSCH in the virtual slot (for example, “S PUSCH " or starting virtual symbol), and the number of virtual symbols to transmit the PUSCH (for example, "L PUSCH " or Virtual symbol length) may be included.

[0248] The information on the time domain resource is stored in the TDRA table (K2, S PUSCH , L PUSCH , and candidate combinations of PUSCH mapping types) may be configured semi-statically, and the combination to be used may be configured from the TDRA table by dynamic notification such as DCI or pre-configuration by higher layer signaling (e.g., RRC signaling).

[0249] In addition, the virtual symbol position S PUSCH and the number of virtual symbols L PUSCH may be set in terminal 200 by, for example, a value associated with a combination of a virtual position and a virtual symbol number (for example, SLIV).

[0250] In Option RA-3, the information on the time domain resource may include, for example, an offset in normal symbol units. The offset may be notified from base station 100 to terminal 200 by at least one of a terminal-specific higher layer signal (for example, an RRC signal) and DCI, separately from the TDRA information. Alternatively, the offset may be included in the TDRA table and notified (in other words, set).

[0251] For example, the virtual slot in which terminal 200 transmits the PUSCH may be specified according to the following equation (8).

number

[0252] Here, n indicates a virtual slot in which terminal 200 receives DCI (or PDCCH) corresponding to PUSCH allocation. μPUSCH indicates the SCS of the carrier or BWP transmitting the PUSCH, and 2 μPDCCH indicates the SCS of a carrier or BWP receiving DCI (or PDCCH). Also, virtualsymbolLengthForPDCCH indicates a virtual symbolLength applied to a PDCCH including DCI corresponding to a PUSCH allocation, and virtualsymbolLengthForPUSCH indicates a virtual symbolLength applied to a PUSCH transmitted by terminal 200.

[0253] For example, terminal 200 may specify a virtual slot in which to transmit the PUSCH according to equation (8). In addition, terminal 200 may specify, for example, S PUSCH The terminal 200 may specify a virtual symbol (in other words, a start position) at which to start transmitting the PUSCH based on, for example, L PUSCH The number of virtual symbols for transmitting the PUSCH may be determined based on the above.

[0254] Furthermore, in Option RA-3, terminal 200 identifies a time domain resource for transmitting a PUSCH by, for example, the method described above, and then shifts the time domain resource for transmitting a PUSCH by an offset based on a normal symbol unit offset.

[0255] According to Option RA-3, for example, a virtual symbol length is set for terminal 200, and a virtual symbol and a virtual slot are configured, so that a time domain resource for Repetition on a symbol-by-symbol basis can be specified by using notification of a time domain resource for PUSCH similar to the normal slot configuration.

[0256] Also, according to Option RA-3, for example, in time domain resource allocation, by applying an offset in normal symbol units, terminal 200 can transmit PUSCH from, for example, any normal symbol position in a normal slot (for example, any normal symbol position including the first symbol). For example, in Option RA-3, it is possible to set the transmission start position of PUSCH with finer granularity than the granularity of virtual symbols. Therefore, in Option RA-3, it is possible to improve the flexibility of PUSCH resource allocation compared to, for example, Option RA-1.

[0257] Note that the time domain resource for the PUSCH may be specified using the virtual symbol and the virtual slot as described above. Meanwhile, the signal (for example, PUSCH) actually transmitted by the terminal 200 is a signal in units of normal symbols, and the terminal 200 transmits, for example, virtualsymbolLength normal symbols in the time interval of the virtual symbol. For example, the terminal 200 may generate a complex symbol group of the number of virtual symbols according to the PUSCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLength normal symbols included in one virtual symbol. Also, the base station 100 may assume that, for example, one complex symbol group is duplicated and mapped to a normal symbol included in one virtual symbol in the terminal 200. Also, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0258] Also, for example, Option RA-3 may be applied to the configuration of Option FS-1 or Option FS-2. When Option RA-3 is applied to Option FS-2, terminal 200 may configure a virtual symbol and a virtual slot, for example, from the symbol position at which the transmission of the PUSCH starts. When Option RA-3 is applied to Option FS-1, terminal 200 may transmit, for example, a part of the normal symbols included in the virtual symbol.

[0259] (Option RA-3:PUCCH) Terminal 200 may, for example, feed back, in the PUCCH, an ACK / NACK indicating success or failure of decoding of the PDSCH. Terminal 200 may also transmit other UCI such as CSI or SR to base station 100 using the PUCCH.

[0260] Furthermore, when transmitting an ACK / NACK for a PDSCH allocated by DCI, terminal 200 may transmit a PUCCH according to resource allocation indicated by DCI in a PDCCH from base station 100, for example.

[0261] Here, the control information included in the DCI may include, for example, information regarding a PUCCH resource. The PUCCH resource may be configured by, for example, a plurality of parameters.

[0262] Among the PUCCH resources, information regarding time domain resources may include, for example, information regarding the virtual symbol position at the beginning of the PUCCH in a virtual slot (e.g., referred to as "startingSymbolIndex" or starting virtual symbol) and the number of virtual symbols for transmitting the PUCCH (e.g., referred to as "nrofSymbols" or virtual symbol length).

[0263] Furthermore, the control information included in the DCI may include, for example, information regarding the timing of transmitting the PUCCH, such as how many virtual slots after the virtual slot in which terminal 200 receives the PDSCH (for example, the number of virtual slots "k").

[0264] For CSI and SR, PUCCH resources may be specified by, for example, a higher layer signal (eg, an RRC signal) from base station 100 to terminal 200.

[0265] In Option RA-3, the information on the time domain resource may include, for example, an offset in normal symbol units. The offset may be notified from base station 100 to terminal 200 by at least one of a terminal-specific higher layer signal (for example, an RRC signal) and DCI, separately from the above-mentioned PUCCH resource. Alternatively, the offset may be included in the parameters of the above-mentioned PUCCH resource and notified (in other words, set).

[0266] For example, the virtual slot in which terminal 200 transmits the PUCCH may be specified according to the following equation (9).

number

[0267] Here, n indicates a virtual slot in which terminal 200 receives a PDSCH. For example, k=0 may correspond to the last virtual slot that overlaps in time with the virtual slot in which the PDSCH is received, among the virtual slots applied to the PUCCH.

[0268] For example, terminal 200 may specify a virtual slot for transmitting PUCCH according to equation (9). Terminal 200 may also specify a virtual symbol at which to start transmitting PUCCH (in other words, a starting position) in the specified virtual slot, for example, based on startingSymbolIndex. Terminal 200 may also specify the number of virtual symbols for transmitting PUCCH, for example, based on nrofSymbols.

[0269] Furthermore, in Option RA-3, terminal 200 identifies the time domain resource for transmitting the PUCCH by, for example, the method described above, and then shifts the time domain resource for transmitting the PUCCH by the offset based on the offset in normal symbol units.

[0270] According to Option RA-3, for example, a virtual symbol length is set for terminal 200, and virtual symbols and virtual slots are configured, so that time domain resources for symbol-by-symbol Repetition can be specified using PUCCH resource notification similar to the normal slot configuration.

[0271] Also, according to Option RA-3, for example, in time domain resource allocation, by applying an offset in normal symbol units, terminal 200 becomes able to transmit PUCCH from, for example, any normal symbol position in a normal slot (for example, any normal symbol position including the leading symbol). For example, in Option RA-3, it becomes possible to set the PUCCH transmission start position with finer granularity than the granularity of virtual symbols. Therefore, in Option RA-3, it is possible to improve the flexibility of PUCCH resource allocation compared to, for example, Option RA-1.

[0272] Note that the time domain resource for PUCCH may be specified using the virtual symbol and the virtual slot as described above. Meanwhile, the signal (for example, PUCCH) actually transmitted by the terminal 200 is a signal in units of normal symbols, and the terminal 200 transmits, for example, virtualsymbolLength normal symbols in the time interval of the virtual symbol. For example, the terminal 200 may generate a complex symbol group of the number of virtual symbols according to the PUCCH resource allocation, and may duplicate and map one complex symbol group to the virtualsymbolLength normal symbols included in one virtual symbol. Also, the base station 100 may assume that, for example, one complex symbol group is duplicated and mapped to a normal symbol included in one virtual symbol in the terminal 200. Also, for example, a common scrambling, data modulation method, layer mapping, or antenna port mapping process may be applied to the complex symbol group included in one virtual symbol.

[0273] Also, for example, Option RA-3 may be applied to the configuration of Option FS-1 or Option FS-2. When Option RA-3 is applied to Option FS-2, terminal 200 may configure a virtual symbol and a virtual slot, for example, from the symbol position where the PUCCH transmission starts. Also, when Option RA-3 is applied to Option FS-1, terminal 200 may transmit, for example, a part of the normal symbols included in the virtual symbol.

[0274] [(5) DMRS arrangement] The allocation of DMRS for the PDSCH received by terminal 200 and the PUSCH and PUCCH transmitted by terminal 200 may be determined (in other words, specified) based on at least the virtual symbol and virtual slot, for example.

[0275] An example of how DMRS allocation is determined will be described below.

[0276] < / option> <option dmrs-1> In Option DMRS-1, for example, base station 100 and terminal 200 may determine (in other words, identify) the allocation of DMRSs to resources used in communication based on virtual symbols and virtual slots. In other words, in Option DMRS-1, information on normal slots and normal symbols does not need to be used to identify the DMRS allocation.

[0277] In Option DMRS-1, for example, a channel estimation result obtained by a DMRS may be used for demodulating data symbols in a virtual slot that includes the DMRS. In other words, a channel estimation result obtained by a DMRS does not need to be used in a virtual slot other than the virtual slot that includes the DMRS.

[0278] In NR, for example, a DMRS used for channel estimation for demodulation may be arranged in resources of PDSCH, PUCCH, and PUSCH. The DMRS may be arranged, for example, in the front of a slot. Also, the DMRS may be arranged in multiple symbols in a slot. Also, in NR, for example, the symbol position where the DMRS is arranged may be specified by parameters such as a mapping type of data (e.g., PDSCH or PUSCH), a PUCCH format, the number of symbols of PDSCH, PUSCH, or PUCCH (e.g., equivalent to the number of normal symbols), or the presence and number of additional DMRS (see, for example, Non-Patent Document 3).

[0279] Fig. 22(a) is a diagram showing an example of DMRS allocation for NR data (e.g., PDSCH or PUSCH). Fig. 22(a) shows an example of DMRS allocation for, for example, mapping type B, 14 symbol allocation, 1-symbol head DMRS (in other words, DMRS symbol allocation at the head of a slot), and the number of additional DMRSs is 3. In Fig. 22(a), DMRSs are allocated to, for example, symbols #0, #3, #6, and #9 in a slot.

[0280] In Option DMRS-1, the DMRS is arranged by replacing the DMRS arrangement for normal slots and normal symbols with virtual slots and virtual symbols, for example.

[0281] In other words, in Option DMRS-1, the arrangement of DMRS in virtual symbols within a virtual slot may be specified based on parameters such as the mapping type of data (e.g., PDSCH or PUSCH), the PUCCH format, the number of virtual symbols of PDSCH, PUSCH or PUCCH, or the presence and number of additional DMRS.

[0282] Figures 22(b) and 22(c) are diagrams showing an example of DMRS allocation in Option DMRS-1. Figure 22(b) shows an example of DMRS allocation when, for example, virtualsymbolLength = 2, and Figure 22(c) shows an example of DMRS allocation when, for example, virtualsymbolLength = 4. Also, Figures 22(b) and 22(c) show an example of DMRS allocation when, for example, mapping type B, 14 virtual symbols are allocated, a 1-symbol head DMRS, and the number of additional DMRSs is 3, similar to Figure 22(a).

[0283] In both Figures 22(b) and 22(c), DMRSs are allocated to virtual symbols #0, #3, #6, and #9 in a virtual slot. Comparing Figure 22(a) with Figures 22(b) and 22(c), although the values ​​of virtualsymbolLength are different, the symbol numbers (e.g., normal symbol numbers or virtual symbol numbers) to which DMRSs are allocated are the same (#0, #3, #6, and #9).

[0284] In this way, according to Option DMRS-1, for example, a virtual symbol length is set for terminal 200, and virtual symbols and virtual slots are configured, so that DMRS allocation for symbol-based Repetition (in other words, virtual slot configuration) can be specified based on the same DMRS allocation method as the normal slot configuration.

[0285] < / option> <option dmrs-2> In Option DMRS-2, for example, base station 100 and terminal 200 may determine (in other words, identify) the allocation of DMRSs used for communication to resources, based on virtual symbols, virtual slots, and normal slots.

[0286] In Option DMRS-2, for example, a channel estimation result obtained by a DMRS may be used for demodulating data symbols in a normal slot that includes the DMRS. In other words, a channel estimation result obtained by a DMRS does not need to be used in a virtual slot other than the virtual slot that includes the DMRS.

[0287] As described above, in NR, for example, a DMRS used for channel estimation for demodulation may be arranged in resources of PDSCH, PUCCH, and PUSCH. The DMRS may be arranged, for example, in the front of a slot. Also, the DMRS may be arranged in multiple symbols in a slot. Also, in NR, for example, the symbol position where the DMRS is arranged may be specified by parameters such as a mapping type of data (e.g., PDSCH or PUSCH), a PUCCH format, the number of symbols of PDSCH, PUSCH, or PUCCH (e.g., equivalent to the number of normal symbols), or the presence and number of additional DMRS (see, for example, Non-Patent Document 3).

[0288] Fig. 23(a) is a diagram showing an example of DMRS allocation for NR data (e.g., PDSCH or PUSCH). Fig. 23(a) shows an example of DMRS allocation for, for example, mapping type B, 14 symbol allocation, 1 symbol top DMRS, and 3 additional DMRSs. In Fig. 23(a), DMRSs are allocated to, for example, symbols #0, #3, #6, and #9 in a slot.

[0289] In Option DMRS-2, the DMRS is arranged by replacing, for example, the DMRS arrangement for Option DMRS-1 and normal slots and normal symbols with virtual slots and virtual symbols. In other words, in Option DMRS-2, the DMRS arrangement in the virtual symbol in the virtual slot may be specified based on parameters such as the mapping type of data (PDSCH or PUSCH), the PUCCH format, the number of virtual symbols of PDSCH, PUSCH, or PUCCH, or the presence and number of additional DMRSs.

[0290] In Option DMRS-2, for example, when a virtual symbol in which a DMRS can be allocated exists that straddles a normal slot boundary, the virtual symbol may be divided into two sub-virtual symbols before and after the normal slot boundary. For example, of the divided sub-virtual symbols, a DMRS may be allocated to the sub-virtual symbol after the normal slot boundary.

[0291] In addition, among the divided sub-virtual symbols, a DMRS may be allocated to the sub-virtual symbol before the slot boundary, or a data symbol may be mapped to it. Also, for example, among the divided sub-virtual symbols, a DMRS may be allocated to the sub-virtual symbol before the slot boundary, and a DMRS may not be allocated to the sub-virtual symbol after the slot boundary.

[0292] Figure 23(b) is a diagram showing an example of DMRS allocation in Option DMRS-2. Figure 23(b) shows an example of DMRS allocation when virtual symbol length is 4. Also, Figure 23(b) shows an example of DMRS allocation when mapping type B, 14 virtual symbols are allocated, a 1-symbol head DMRS, and the number of additional DMRSs is 3, similar to Figure 23(a).

[0293] In Fig. 23(b), DMRSs are allocated to virtual symbols #0, #3, #6, and #9 in a virtual slot. Comparing Fig. 23(a) and Fig. 23(b), although the values ​​of virtualsymbolLength are different, the symbol numbers (for example, normal symbol numbers or virtual symbol numbers) to which DMRSs are allocated are the same (#0, #3, #6, and #9).

[0294] Also, in Fig. 23(b), virtual symbols #3 and #10 straddle a normal slot boundary. Therefore, as shown in Fig. 23(b), virtual symbols #3 and #10 are divided into two sub-virtual symbols before and after the normal slot boundary, and for example, a DMRS is allocated to the sub-virtual symbol after the normal slot boundary. On the other hand, in Fig. 23(b), in virtual symbols #3 and #10, a DMRS is not allocated (for example, data is allocated) to the sub-virtual symbol before the normal slot boundary.

[0295] In this way, according to Option DMRS-2, for example, a virtual symbol length is set for terminal 200, and virtual symbols and virtual slots are configured, so that DMRS allocation for symbol-based Repetition (in other words, virtual slot configuration) can be specified based on the same DMRS allocation method as the normal slot configuration.

[0296] As described above, for example, there may be cases where the channel estimation result obtained by a DMRS is applicable to demodulation of data symbols in a normal slot including the DMRS (in other words, the DMRS is not applicable to a normal slot other than the normal slot including the DMRS). Even in such cases, according to Option DMRS-2, for example, the accuracy of channel estimation can be improved by a DMRS placed in a virtual symbol corresponding to at least one of the normal slots (in FIG. 23, the sub-virtual symbol after the normal slot boundary) in a time interval of a virtual symbol spanning a normal slot boundary.

[0297] [(6) Additional Repetition] For example, to PDSCH reception, PUSCH transmission, or PUCCH transmission based on virtual symbols or virtual slots configured by applying symbol-based repetition, "virtual slot-based repetition," "repetition on a resource basis allocated by a virtual symbol," or "virtual symbol group-based repetition" may be further applied.

[0298] Below, examples of each Repetition will be explained.

[0299] < / option> <option r-1> In NR Rel.15, for example, slot-based repetition can be applied to PDSCH, PUCCH, and PUSCH as described above. In Option R-1, for example, symbol-based repetition is applied to configure virtual symbols and virtual slots, and further, virtual slot-based repetition is applied. For example, in Option R-1, base station 100 and terminal 200 control repetition in communication based on the virtual slot unit.

[0300] Fig. 24 is a diagram showing an example of Repetition in units of virtual slots. In Fig. 24, virtualsymbolLength=2, and the number of Repetitions in units of virtual slots, numberofRepetition=2. For example, as shown in Fig. 24, when repetition in units of virtual slots is applied, a common time domain resource allocation may be applied over numberofRepetition virtual slots.

[0301] According to Option R-1, for example, as described in Option FS-1-4, even when the upper limit value that can be set for the virtual symbol length is small (in other words, when the number of repetitions that can be applied to the symbol-based repetition is small), the accuracy of channel estimation can be improved by using the repetition on a virtual slot basis.

[0302] Furthermore, the coverage can be expanded by combining the symbol-based repetition and the virtual slot-based repetition. In other words, the virtual slot-based repetition can compensate for the coverage expansion effect caused by the reduction in the number of repetitions that can be applied to the symbol-based repetition.

[0303] Here, since the same signal is repeatedly transmitted in the repetition, the frequency utilization efficiency may decrease due to the increase in the number of repetitions. On the other hand, depending on the channel condition, the receiving side may be able to demodulate and decode the data without receiving all the repetitions set.

[0304] For example, in downlink data transmission, if terminal 200 successfully demodulates and decodes data before receiving the set (in other words, specified) number of repetitions of data, base station 100 can stop the repetition transmission midway (early termination) by feeding back an ACK to base station 100.

[0305] Also, for example, in uplink data transmission, if base station 100 is able to demodulate and decode data before receiving the data for the set number of repetitions, it is possible to stop the repetition transmission of terminal 200 midway (early termination) by notifying terminal 200 of an ACK.

[0306] In this way, by applying early termination, it is possible to suppress a decrease in frequency utilization efficiency.

[0307] When applying early termination, it is preferable for the receiving side to demodulate and decode data after receiving all the coded bits. On the other hand, with symbol-based repetition, all the coded bits can be received only after the last virtual symbol has been received. This makes it difficult to apply early termination.

[0308] In contrast, in Option R-1, for example, by combining symbol-based repetition and virtual slot-based repetition, the receiving side can receive all the coded bits every time one virtual slot is received. Therefore, in Option R-1, early termination in virtual slot units can be applied. Therefore, it is possible to obtain the effect of suppressing the decrease in frequency utilization efficiency due to early termination while improving channel estimation accuracy by symbol-based repetition.

[0309] In addition, in FIG. 24, virtual slot-based repetition for PUSCH has been described, but Option R-1 may be applied to, for example, PDSCH, PUCCH, and PUSCH to which slot-based repetition is applied in NR Rel.15, and may also be applied to other channels / signals such as PDCCH, CSI-RS, or SRS.

[0310] < / option> <option r-2> In NR Rel.16, for example, as described above, minislot-based repetition is applicable to PUSCH, in which one or more PUSCHs are repeatedly transmitted within one slot. In Option R-2, for example, symbol-based repetition is applied to configure a virtual symbol or virtual slot, and further, resource-based repetition is applied that is allocated using the virtual symbol or virtual slot. For example, in Option R-2, base station 100 and terminal 200 control repetition in communication based on a unit of multiple virtual symbols (for example, a resource unit allocated to a signal in virtual symbol units).

[0311] Fig. 25 is a diagram showing an example of repetition in units of resources allocated by virtual symbols. In Fig. 25, virtualsymbolLength=2, and the number of repetitions of PUSCH allocated using virtual symbol or virtual slot units, numberofRepetition=3. In Fig. 25, for example, resources are allocated to PUSCH in units of seven virtual symbols, so repetition in units of seven virtual symbols is applied.

[0312] According to Option R-2, for example, as described in Option FS-1-4, even if the upper limit that can be set for the virtual symbol length is small, the accuracy of channel estimation can be improved by repetition in resource units allocated using virtual symbols.

[0313] Furthermore, the coverage can be expanded by combining the symbol-based repetition and the resource-based repetition allocated using the virtual symbol. In other words, the resource-based repetition allocated using the virtual symbol can compensate for the coverage expansion effect caused by the reduction in the number of repetitions that can be applied to the symbol-based repetition.

[0314] Furthermore, Option R-2, like Option R-1, allows for early termination to be applied for each resource allocated using virtual symbols or virtual slots, thereby making it possible to prevent a decrease in frequency utilization efficiency.

[0315] In FIG. 25, the repetition for the PUSCH to which the repetition on a PUSCH unit basis is applied in NR Rel.16 has been described. However, Option R-2 may be applied to, for example, the PDSCH and the PUCCH, or may be applied to other channels / signals such as the PDCCH, the CSI-RS, or the SRS.

[0316] < / option> <option r-3> In Option R-3, for example, a virtual symbol or a virtual slot is configured by applying repetition in symbol units, and further, repetition is applied in virtual symbol group units.

[0317] Here, a "virtual symbol group" (or a virtual symbol group) includes, for example, a plurality of virtual symbols.

[0318] For example, in Option R-3, the base station 100 and the terminal 200 control the repetition in communication based on a unit of a plurality of virtual symbols (for example, a unit of a virtual symbol group).

[0319] 26 is a diagram showing an example of Repetition in units of a virtual symbol group, in which virtualsymbolLength=2, the number of repetitions in units of a virtual symbol group, numberofRepetition,=2, and the number of virtual symbols included in the virtual symbol group=2.

[0320] 26, for example, one virtual symbol group is made up of two virtual symbols, virtual symbols #0 and #1, and repetition is performed numberofRepetition=2 times for the virtual symbol group including the two virtual symbols.

[0321] For example, comparing the case of virtual symbol length = 4 in Fig. 26 with the case of virtual symbol length = 4 in Fig. 13 (one example of Option FS-1-1), both have the same number of OFDM symbols (in other words, normal symbols) for repetition. For example, in Fig. 13, four normal symbols #0 are arranged consecutively. On the other hand, in Fig. 26, the four normal symbols #0 are arranged in groups of two symbols.

[0322] In this way, according to Option R-3, for example, data symbols including the same data or DMRS can be dispersed in time within a slot or a virtual slot, thereby obtaining a time diversity effect.

[0323] Above, we have explained Option R-1, Option R-2, and Option R-3.

[0324] <How to set additional Repetition> Next, a method for setting an additional Repetition (in other words, a notification method) will be described.

[0325] The presence or absence of additional repetition and the number of repetitions may be semi-statically notified by, for example, a terminal-specific higher layer signal (for example, an RRC signal). In other words, the presence or absence of additional repetition and the number of repetitions may be notified in the same manner as the PDSCH / PUSCH / PUCCH repetition in NR Rel.15 (for example, see Non-Patent Document 5 or 6).

[0326] In addition, the presence or absence of additional repetition and the number of repetitions may be notified, for example, by being included in the above-mentioned PDSCH or PUSCH TDRA table or the parameters of the PUCCH resource. In other words, the presence or absence of additional repetition and the number of repetitions may be notified in the same manner as the PUSCH repetition in NR Rel. 16 (for example, see Non-Patent Document 7).

[0327] Also, for example, the repetition method applied may differ depending on the operation mode of terminal 200. For example, normal slot-based or minislot-based repetition may be applied to an operation mode in which the number of repetitions is equal to or less than a threshold, and a combination of the above-mentioned symbol-based repetition and normal slot-based or minislot-based repetition may be applied to an operation mode in which the number of repetitions is greater than the threshold (in other words, coverage extension mode).

[0328] <Early termination> For example, when applying early termination to the PDSCH, terminal 200 may transmit an ACK to base station 100 after receiving a signal of each virtual slot (for example, in the case of Option R-1) or a PDSCH allocated using a virtual symbol or a virtual slot (for example, in the case of Option R-2). The ACK may be transmitted using, for example, the PUCCH.

[0329] Furthermore, for example, when applying early termination to PUSCH or PUCCH, terminal 200 may assume that a notification indicating early termination may be transmitted from base station 100 after transmitting a signal of each virtual slot (e.g., in the case of Option R-1), or a PUSCH or PUCCH allocated using a virtual symbol or virtual slot (e.g., in the case of Option R-2), and may monitor a control signal for that notification.

[0330] Here, the control signal indicating early termination may be included, for example, in DCI transmitted in a group-shared PDCCH (e.g., DCI format 2-1 or DCI format 2-4), or may be included in DCI transmitted in a terminal-specific PDCCH (e.g., DCI format 0-0, DCI format 0-1, or DCI format 0-2).

[0331] Furthermore, for example, terminal 200 may replace a notification of ACK by a Downlink Feedback Indicator (DFI), which notifies ACK / NACK of an uplink configured grant transmission, with early termination. For example, when early termination is notified, terminal 200 may stop uplink transmission (for example, PUSCH or PUCCH) even if transmission has not been performed a preset number of times of Repetition.

[0332] [(7) Terminal processing time] In NR, processing times of terminal 200 are specified, such as the minimum signal processing time from the timing of receiving a PDSCH by terminal 200 to the timing of transmitting ACK / NACK feedback (see, for example, Non-Patent Document 6), the minimum signal processing time from the timing of receiving a PDCCH that allocates a PUSCH to the timing of transmitting a PUSCH (see, for example, Non-Patent Document 6), the CSI calculation time (see, for example, Non-Patent Document 6), and the BWP switching time (see, for example, Non-Patent Document 5).

[0333] In this embodiment, for example, the following rules may be applied to the processing time (for example, minimum signal processing time) of terminal 200 when virtual symbols and virtual slots are configured by applying symbol-based Repetition.

[0334] < / option> <option pt-1> In Option PT-1, when virtual symbols and virtual slots are configured by applying symbol-based Repetition, the processing time (e.g., minimum signal processing time) of terminal 200 may be, for example, a symbol-based (in other words, normal symbol-based) value specified in NR Rel.15 or NR Rel.16.

[0335] For example, even when symbol-based Repetition is applied, the signal actually transmitted by terminal 200 is in normal symbol units. For example, terminal 200 transmits and receives virtualsymbolLength normal symbols in a time interval of a virtual symbol. According to Option PT-1, the processing time (e.g., minimum signal processing time) of terminal 200 can be specified to be the same value as that specified in NR Rel.15 or NR Rel.16 (in other words, no change).

[0336] < / option> <option pt-2> In Option PT-2, the processing time (e.g., minimum signal processing time) of terminal 200 when virtual symbols and virtual slots are configured by applying symbol-based Repetition may be specified to a value different from that of NR Rel.15 or NR Rel.16.

[0337] For example, the processing time of terminal 200 when virtual symbols and virtual slots are configured may be specified as a value obtained by adding an offset (e.g., several symbols) to the processing time of terminal 200 specified in NR Rel.15 or Rel.16. Also, the processing time of terminal 200 when virtual symbols and virtual slots are configured by applying symbol-based Repetition may be specified as a value obtained by multiplying the processing time of terminal 200 specified in NR Rel.15 or Rel.16 by a coefficient (e.g., virtualsymbolLength).

[0338] When applying symbol-based Repetition, terminal 200 may need to perform additional processing, such as combining DMRSs and applying channel estimation, and therefore it may not be possible to apply the processing time for terminal 200 specified in NR Rel. 15 or Rel. 16.

[0339] In contrast, according to Option PT-2, by specifying a value for the processing time of terminal 200 when applying symbol-based Repetition that is different from the processing time of terminal 200 specified in NR Rel. 15 or Rel. 16, it is possible to appropriately specify the time timing of the PUCCH for transmitting ACK / NACK or the transmission timing of the PUSCH to terminal 200.

[0340] < / option> <option pt-3> In Option PT-3, for example, the processing time (eg, minimum signal processing time) of terminal 200 when virtual symbols and virtual slots are configured by applying symbol-based Repetition may be set based on certain conditions.

[0341] For example, when a certain condition is satisfied, the processing time of terminal 200 when symbol-based Repetition is applied may be the processing time of terminal 200 specified in NR Rel.15 or Rel.16. On the other hand, when a certain condition is not satisfied, the processing time of terminal 200 when symbol-based Repetition is applied may be a value different from the processing time of terminal 200 specified in NR Rel.15 or Rel.16.

[0342] In other words, Option PT-3 may switch between Option PT-1 and Option PT-2 based on whether a certain condition is satisfied.

[0343] The certain condition may be, for example, that the additional DMRS is not applied. In this case, for example, the minimum signal processing time from the timing of receiving the PDSCH to the timing of transmitting the ACK / NACK feedback may be different based on whether the additional DMRS is applied. For example, when the additional DMRS is not applied, the minimum signal processing time specified in NR Rel.15 or Rel.16 is applied (in other words, no change from NR), and when the additional DMRS is applied, the newly specified minimum signal processing time may be applied.

[0344] Note that the certain condition is not limited to the condition regarding the presence or absence of an additional DMRS, but may be another condition. For example, the minimum signal processing time may be different based on the mapping type of the PDSCH.

[0345] [(8)PDCCH] The above-mentioned method of configuring virtual symbols and virtual slots by applying symbol-by-symbol repetition may be applied to the PDCCH.

[0346] When symbol-based Repetition is applied to the PDCCH, for example, the virtualsymbolLength may be semi-statically set by a cell-specific or terminal-specific higher layer signal (for example, an RRC signal).

[0347] Also, as described above in Option C-4, virtual symbol length may be included in the parameters of the CORESET setting, for example.

[0348] For example, when symbol-based repetition is applied to the above-mentioned PDSCH, PUSCH, or PUCCH, symbol-based repetition for the PDCCH has a high affinity therewith, making resource allocation easier.

[0349] Furthermore, in the case of PDCCH, for example, repetition may be applied in units of the number of symbols included in a CORESET (as an example, any one of 1 to 3 symbols). When PDCCH is repetitive in units of the number of symbols included in a CORESET, it becomes possible to share a search space (or CORESET) between terminals 200 having different PDCCH coverage extension levels (in other words, the number of repetitions).

[0350] [(9) Application of code division multiplexing or space-time coding] As described above, even when symbol-based Repetition is applied, the signals that terminal 200 actually transmits and receives are in normal symbol units, and terminal 200 transmits and receives virtualsymbolLength normal symbols in the time interval of a virtual symbol.

[0351] For example, an orthogonal code (e.g., an orthogonal cover code (OCC)) may be applied to multiple (e.g., virtual symbol Length) normal symbols included in one virtual symbol. By applying OCC, for example, signals for multiple terminals 200 to which different OCCs are applied can be code division multiplexed (CDM) in the same time and frequency resources. By applying CDM, it is possible to improve frequency utilization efficiency by repetition.

[0352] Furthermore, for example, when the transmitting side has multiple antenna ports, space-time block coding (STBC) may be applied to multiple (for example, virtualsymbolLength) symbols included in one virtual symbol (see, for example, Non-Patent Document 8). By applying STBC, a transmission diversity effect can be obtained, and the coverage can be further improved.

[0353] [(10) Conflict with uplink and downlink patterns] In NR, for example, terminal 200 can identify the type of slot or the type of symbol in the slot (for example, any of downlink symbol, uplink symbol, and Flexible symbol) by SFI notification from base station 100. The SFI may be notified from base station 100 to terminal 200 by, for example, a higher layer signal (for example, an RRC signal) or a group common downlink control signal (Group common PDCCH).

[0354] In NR, for example, some of the time domain resources for transmission and reception may conflict (in other words, overlap or collide) with information on the uplink and downlink (hereinafter also referred to as "uplink and downlink patterns") notified by the SFI. For example, some of the time domain resources (e.g., uplink symbols) of the PUSCH may be set to downlink symbols in the SFI. In this case, terminal 200 may not transmit the PUSCH in the slot (in other words, may drop the transmission). In other words, terminal 200 may transmit the PUSCH using some symbols where there is no conflict between the PUSCH resources and the uplink and downlink patterns.

[0355] Furthermore, as described above, even when symbol-based Repetition is applied, the signals that terminal 200 actually transmits and receives are in normal symbol units, and terminal 200 transmits and receives virtualsymbolLength normal symbols in the time interval of a virtual symbol.

[0356] In addition, the type of slot or the type of symbol in a slot notified by the SFI is assumed to be set, for example, in units of normal symbols or normal slots. In other words, the types of normal symbols or normal slots included in a virtual symbol or virtual slot may be different.

[0357] As a result, for example, in the time domain resource for transmission and reception specified by the above-mentioned method, some of the normal symbols included in the virtual symbol may conflict with the uplink / downlink pattern notified by the SFI. In this case, the following method may be applied as the operation of terminal 200.

[0358] <Method 1> In method 1, terminal 200 may determine not to transmit or receive (in other words, drop) all normal symbols included in a virtual symbol.

[0359] <Method 2> In method 2, the terminal 200 may perform transmission and reception using some of the normal symbols that do not conflict with the uplink and downlink patterns among the normal symbols included in the virtual symbol. In other words, the terminal 200 may determine not to transmit or receive (in other words, to drop) the normal symbols that conflict with the uplink and downlink patterns among the normal symbols included in the virtual symbol.

[0360] <Method 3> In method 3, terminal 200 may switch between method 1 and method 2 described above, based on whether or not the above-mentioned CDM or STBC is applied, for example.

[0361] For example, when CDM or STBC is applied, terminal 200 does not need to transmit and receive all normal symbols included in a virtual symbol (in other words, method 1 may be applied).On the other hand, when CDM or STBC is not applied, terminal 200 may transmit and receive using some of the normal symbols included in a virtual symbol that do not cause conflict with uplink and downlink patterns (in other words, method 2 may be applied).

[0362] Furthermore, terminal 200 may switch between method 1 and method 2 based on, for example, the type of channel / signal, regardless of whether CDM or STBC is applied.

[0363] An example of the operation of Repetition in symbol units has been described above.

[0364] Next, an example of processing in the terminal 200 will be described.

[0365] FIG. 27 is a flowchart showing an example of operation related to downlink data reception (for example, PDSCH reception and PUCCH transmission) in terminal 200 according to the present embodiment.

[0366] 27, terminal 200 acquires, for example, information on symbol-based Repetition (ST101). The information on symbol-based Repetition may be, for example, information on the number of normal symbols included in one virtual symbol (for example, virtualsymbolLength). For example, the process of ST101 may include the process described in "(2) Example of setting virtualsymbolLength (Configuration)" above.

[0367] Terminal 200 configures (in other words, sets) a virtual symbol and a virtual slot (ST102). For example, the process of ST102 may include the process described in "(3) Example of configuration of virtual symbol and virtual slot" above.

[0368] Terminal 200 obtains, for example, control information related to PDSCH reception and control information related to PUCCH transmission (ST103).

[0369] Terminal 200 receives DCI in, for example, the PDCCH (ST104). Also, terminal 200 receives and decodes the PDSCH in, for example, the downlink resource indicated by the DCI (ST105).

[0370] Furthermore, terminal 200 generates an ACK / NACK based on, for example, the result of decoding the PDSCH (ST106), and transmits the ACK / NACK to base station 100 using the PUCCH (ST107).

[0371] For example, the processing in ST104 to ST107 may include at least one of the processing described in "(4) Resource allocation", "(5) DMRS allocation", "(7) Terminal processing time", and "(8) PDCCH" above.

[0372] For example, when Option FS-2 in “(3) Example of configuration of virtual symbols and virtual slots” is applied, terminal 200 may obtain resource allocation information regarding time domain resources in the processing of ST103 or ST104, and then configure virtual symbols and virtual slots based on information regarding virtual symbol length, as in ST102.

[0373] FIG. 28 is a flowchart showing an example of operation related to uplink data transmission (eg, PUSCH transmission) in terminal 200 according to the present embodiment.

[0374] 28, terminal 200 acquires, for example, information on symbol-based Repetition (ST201). The information on symbol-based Repetition may be, for example, information on the number of normal symbols included in one virtual symbol (for example, virtualsymbolLength). For example, the process of ST201 may include the process described in "(2) Example of setting virtualsymbolLength (Configuration)" above.

[0375] Terminal 200 configures (in other words, sets) a virtual symbol and a virtual slot (ST202). For example, the processing in ST202 may include the processing described in "(3) Example of configuration of virtual symbol and virtual slot" above.

[0376] Terminal 200 obtains, for example, control information related to PUSCH transmission (ST203).

[0377] Terminal 200 receives DCI, for example, in the PDCCH (ST204).

[0378] Furthermore, terminal 200 generates a PUSCH based on, for example, information about PUSCH transmission and uplink resources indicated by DCI, and transmits the PUSCH to base station 100 (ST205).

[0379] For example, the processing in ST204 and ST205 may include the processing described in "(4) Resource allocation", "(5) DMRS allocation", "(7) Terminal processing time", or "(8) PDCCH" above.

[0380] In addition, in Figures 27 and 28, the above-mentioned "(6) Additional Repetition", "(9) Application of code division multiplexing or space-time coding", and "(10) Conflict with uplink and downlink patterns" are not applied. However, in the present embodiment, these may be applied.

[0381] An example of the operation of the terminal 200 has been described above.

[0382] According to this embodiment, terminal 200 controls communication based on a virtual symbol with multiple normal symbols as one unit, or a virtual slot composed of multiple virtual symbols. This control can improve the accuracy of channel estimation in wireless communication, for example, by repetition of multiple normal symbols that compose a virtual symbol (in other words, symbol-by-symbol repetition).

[0383] The above describes each embodiment according to one embodiment of the present disclosure.

[0384] (Other embodiments) In the above-described embodiment, the terms "Virtual symbol" and "Virtual slot" are used for convenience, but other names may be used. For example, the Virtual symbol / Virtual slot may be called "Super symbol / Super slot", "hyper symbol / hyper slot", "Coverage Enhancement (CE) symbol / CE slot", "Pseudo symbol / Pseudo slot", or "Extended symbol / Extended slot".

[0385] Furthermore, the normal symbol and normal slot may be called, for example, a "Non-virtual symbol / Non-Virtual slot", a "Non-super symbol / Non-super slot", a "Non-hyper symbol / Non-hyper slot", a "Non-CE symbol / Non-CE slot", a "Non-Pseudo symbol / Non-Pseudo slot", or a "Non-extended symbol / Non-extended slot". The normal symbol and normal slot may simply be called a "symbol / slot".

[0386] In addition, in the above embodiment, downlink communication and uplink communication between base station 100 and terminal 200 are assumed. However, an embodiment of the present disclosure is not limited to this, and may be applied to communication between terminals (for example, sidelink communication).

[0387] Furthermore, the downlink control channel, the downlink data channel, the uplink control channel, and the uplink data channel are not limited to the PDCCH, the PDSCH, the PUCCH, and the PUSCH, respectively, and may be control channels with other names.

[0388] In addition, in the above-described embodiment, the higher layer signaling is assumed to be RRC signaling, but this may be replaced with Medium Access Control (MAC) signaling and notification by DCI, which is physical layer signaling.

[0389] Furthermore, in the above-described embodiments, the unit of the time domain resource is not limited to slots and symbols, but may be, for example, a time domain resource unit such as a frame, subframe, slot, subslot, or symbol, or may be another time domain resource unit.

[0390] In addition, the parameters applied in the above-mentioned embodiment are merely examples and are not limited to the above. For example, at least one of the parameters such as the number of normal symbols constituting a virtual symbol (virtual symbol length), the offset in normal symbol units, the slot offset, the symbol position, and the number of symbols is not limited to the value in the above-mentioned embodiment and may be another value.

[0391] Furthermore, in the above-described embodiment, a case has been described in which DMRS is used, but the reference signal is not limited to DMRS and may be another reference signal.

[0392] Furthermore, in the above-described embodiment, frequency hopping may be applied. In this case, the frequency hopping interval may be determined (in other words, specified) based on at least the virtual symbol and the virtual slot.

[0393] The setting method and operation of frequency hopping will be described below.

[0394] For example, base station 100 and terminal 200 may determine (in other words, specify) the frequency hopping interval (e.g., the number of virtual symbols included in each hop interval) to be used in communication and the allocation of DMRS resources for each hop based on the virtual symbols and virtual slots. In other words, it is not necessary to use information on normal slots and normal symbols to specify the frequency hopping interval and the allocation of DMRS resources for each hop.

[0395] In NR, for example, frequency hopping may be applied to PUCCH and PUSCH. Frequency hopping may be applied, for example, so that the number of symbols included in each hop interval is equal to the number of allocated symbols. For example, when the number of allocated symbols is N symbols, the number of symbols included in the first frequency hop interval may be ceil(N / 2) symbols, and the number of symbols included in the second frequency hop interval may be N-ceil(N / 2) symbols. In NR, for example, whether or not frequency hopping is applied may be set by higher layer signaling or may be notified by DCI.

[0396] In the above-described embodiment, when frequency hopping is applied, for example, frequency hopping operations for normal slots and normal symbols are replaced with virtual slots and virtual symbols. In other words, the allocation of DMRS resources for frequency hopping intervals and each hop may be specified based on, for example, the number of virtual symbols in a virtual slot. That is, when the number of allocated virtual symbols is N, the number of virtual symbols included in the first frequency hop interval may be ceil(N / 2), and the number of virtual symbols included in the second frequency hop interval may be N-ceil(N / 2). Furthermore, the symbol numbers (for example, normal symbol numbers or virtual symbol numbers) to which the DMRS resources included in each hopping interval are allocated are the same.

[0397] In this way, for example, a virtual symbol length is set for terminal 200, and virtual symbols and virtual slots are configured, so that frequency hopping and DMRS allocation for symbol-based Repetition (in other words, virtual slot configuration) can be characterized based on the same frequency hopping operation as the normal slot configuration, and it is possible to simultaneously obtain the frequency diversity effect of frequency hopping and the effect of improving channel estimation accuracy by symbol-based Repetition.

[0398] The number of virtual symbols included in each frequency hopping interval (frequency hop) and the number of normal symbols included in each virtual symbol may be different.

[0399] <5G NR system architecture and protocol stack> 3GPP continues to work on the next release of the fifth generation of mobile phone technology (also known simply as "5G"), which includes the development of a new radio access technology (NR) that will operate in the frequency range up to 100 GHz. The first version of the 5G standard was completed at the end of 2017, which will allow for the prototyping and commercial deployment of 5G NR compliant devices (e.g. smartphones).

[0400] For example, the system architecture generally assumes a Next Generation - Radio Access Network (NG-RAN) with gNBs. The gNBs provide UE-side termination of NG radio access user plane (SDAP / PDCP / RLC / MAC / PHY) and control plane (RRC) protocols. The gNBs are connected to each other by an Xn interface. The gNBs are also connected to a Next Generation Core (NGC) by a Next Generation (NG) interface, more specifically to an Access and Mobility Management Function (AMF) (e.g., a specific core entity performing AMF) by an NG-C interface, and to a User Plane Function (UPF) (e.g., a specific core entity performing UPF) by an NG-U interface. The NG-RAN architecture is shown in Figure 29 (see, for example, 3GPP TS 38.300 v15.6.0, section 4).

[0401] The NR user plane protocol stack (see, for example, 3GPP TS 38.300, section 4.4.1) includes the Packet Data Convergence Protocol (PDCP) (see section 6.4 of TS 38.300), Radio Link Control (RLC) (see section 6.3 of TS 38.300), and Medium Access Control (MAC) (see section 6.2 of TS 38.300) sublayers, which are terminated on the network side at the gNB. A new Access Stratum (AS) sublayer (Service Data Adaptation Protocol (SDAP)) is also introduced on top of PDCP (see, for example, 3GPP TS 38.300, section 6.5). A control plane protocol stack is also defined for NR (see, for example, TS 38.300, section 4.4.2). An overview of Layer 2 functions is given in section 6 of TS 38.300. The functions of the PDCP, RLC and MAC sublayers are listed in clauses 6.4, 6.3 and 6.2 of TS 38.300, respectively. The functions of the RRC layer are listed in clause 7 of TS 38.300.

[0402] For example, the Medium-Access-Control layer handles logical channel multiplexing and scheduling and scheduling-related functions, including handling various numerologies.

[0403] For example, the physical layer (PHY) is responsible for coding, PHY HARQ processing, modulation, multi-antenna processing, and mapping of signals to appropriate physical time-frequency resources. The physical layer also handles mapping of transport channels to physical channels. The physical layer provides services to the MAC layer in the form of transport channels. A physical channel corresponds to a set of time-frequency resources used for the transmission of a particular transport channel, and each transport channel is mapped to a corresponding physical channel. For example, the physical channels include the PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), and PUCCH (Physical Uplink Control Channel) as uplink physical channels, and the PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel), and PBCH (Physical Broadcast Channel) as downlink physical channels.

[0404] NR use cases / deployment scenarios may include enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine type communication (mMTC), which have diverse requirements in terms of data rates, latency, and coverage. For example, eMBB is expected to support peak data rates (20 Gbps in downlink and 10 Gbps in uplink) and user-experienced data rates that are about three times higher than those offered by IMT-Advanced. On the other hand, for URLLC, more stringent requirements are imposed on ultra-low latency (0.5 ms for user plane latency in UL and DL respectively) and high reliability (1-10-5 within 1 ms). Finally, mMTC preferably requires high connection density (1,000,000 devices / km in urban environments). 2 ), wide coverage in hostile environments, and extremely long battery life (15 years) for a low-cost device.

[0405] Therefore, OFDM numerology (e.g., subcarrier spacing, OFDM symbol length, cyclic prefix (CP) length, number of symbols per scheduling interval) suitable for one use case may not be valid for other use cases. For example, low latency services may preferably require a shorter symbol length (and therefore a larger subcarrier spacing) and / or fewer symbols per scheduling interval (also called TTI) than mMTC services. Furthermore, deployment scenarios with large channel delay spreads may preferably require a longer CP length than scenarios with small delay spreads. Subcarrier spacing may be optimized accordingly to maintain similar CP overhead. NR may support one or more subcarrier spacing values. Correspondingly, subcarrier spacings of 15 kHz, 30 kHz, 60 kHz... are currently considered. The symbol length Tu and subcarrier spacing Δf are directly related by the formula Δf=1 / Tu. Similar to LTE systems, the term "resource element" can be used to mean the smallest resource unit consisting of one subcarrier for the length of one OFDM / SC-FDMA symbol.

[0406] In the new radio system 5G-NR, for each numerology and each carrier, a resource grid of subcarriers and OFDM symbols is defined for the uplink and downlink, respectively. Each element of the resource grid is called a resource element and is specified based on a frequency index in the frequency domain and a symbol position in the time domain (see 3GPP TS 38.211 v15.6.0).

[0407] <Functional separation between NG-RAN and 5GC in 5G NR> Figure 30 shows the functional separation between NG-RAN and 5GC. The logical node of NG-RAN is gNB or ng-eNB. 5GC has logical nodes AMF, UPF, and SMF.

[0408] For example, the gNB and ng-eNB host the following main functions: - Radio Resource Management functions such as Radio Bearer Control, Radio Admission Control, Connection Mobility Control, dynamic allocation (scheduling) of resources to UEs in both uplink and downlink; - IP header compression, encryption, and integrity protection of data; - Selection of the AMF at UE attach time if routing to the AMF cannot be determined from information provided by the UE; - Routing of user plane data towards the UPF; - Routing of control plane information towards AMF; - Setting up and tearing down connections; - Scheduling and sending paging messages; - Scheduling and transmission of system broadcast information (AMF or Operation, Admission, Maintenance (OAM) origin); - Configuration of measurements and measurement reporting for mobility and scheduling; - Transport level packet marking in the uplink; - Session management; - Support for network slicing; - Management of QoS flows and their mapping to data radio bearers; - Support for UEs in RRC_INACTIVE state; - NAS message delivery function; - Sharing of radio access networks; - Dual connectivity; - Close cooperation between NR and E-UTRA.

[0409] The Access and Mobility Management Function (AMF) hosts the following main functions: - Ability to terminate Non-Access Stratum (NAS) signalling; - NAS signaling security; - Access Stratum (AS) security control; - 3GPP Core Network (CN) inter-node signalling for mobility between access networks; - Reachability to idle mode UEs (including control and execution of paging retransmissions); - Managing the registration area; - Support for intra-system and inter-system mobility; - Access authentication; - Access authorization including roaming privilege checks; - Mobility management control (subscription and policies); - Support for network slicing; - Select the Session Management Function (SMF).

[0410] Additionally, the User Plane Function (UPF) hosts the following main functions: - anchor points for intra-RAT mobility / inter-RAT mobility (if applicable); - External PDU (Protocol Data Unit) Session Points for interconnection with data networks; - Packet routing and forwarding; - Packet inspection and policy rule enforcement for the user plane part; - Traffic usage reporting; - uplink classifier to support routing of traffic flows to the data network; - Branching Point for supporting multi-homed PDU session; - QoS processing for the user plane (e.g., packet filtering, gating, UL / DL rate enforcement); - Verification of uplink traffic (mapping to the QoS flow of the SDF); - Downlink packet buffering and trigger function for downlink data notification.

[0411] Finally, the Session Management Function (SMF) hosts the following main functions: - Session management; - IP address allocation and management for the UE; - Selection and control of the UPF; - Traffic steering setting function in the User Plane Function (UPF) for routing traffic to the appropriate destination; - Enforcement of control part policies and QoS; - Notification of downlink data.

[0412] <Procedures for RRC connection setup and reconfiguration> Figure 31 shows some of the interactions between the UE, gNB, and AMF (5GC entity) in the NAS part when the UE transitions from RRC_IDLE to RRC_CONNECTED (see TS 38.300 v15.6.0).

[0413] RRC is a higher layer signaling (protocol) used for UE and gNB configuration. With this transition, the AMF prepares UE context data (which includes, for example, PDU session context, security keys, UE Radio Capability, UE Security Capabilities, etc.) and sends it to the gNB 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 reconfigures to set up Signaling Radio Bearer 2 (SRB2) and Data Radio Bearer (DRB) by sending an RRCReconfiguration message to the UE and receiving an RRCReconfigurationComplete from the UE. For signaling-only connections, the steps related to RRCReconfiguration are omitted since SRB2 and DRB are not set up. Finally, the gNB informs the AMF that the setup procedure is complete with an INITIAL CONTEXT SETUP RESPONSE.

[0414] Therefore, the present disclosure provides an entity (e.g., AMF, SMF, etc.) of a 5th Generation Core (5GC), comprising: a control circuit that operatively establishes a Next Generation (NG) connection with a gNodeB; and a transmitter that operatively 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. Then, the UE transmits in uplink or receives in downlink based on the resource allocation configuration.

[0415] <IMT usage scenarios after 2020> Figure 32 shows some use cases for 5G NR. The 3rd generation partnership project new radio (3GPP NR) considers three use cases that were envisioned by IMT-2020 to support a wide variety of services and applications. The first phase of specifications for enhanced mobile-broadband (eMBB) has been completed. Current and future work includes standardization for ultra-reliable and low-latency communications (URLLC) and massive machine-type communications (mMTC), in addition to expanding support for eMBB. Figure 32 shows some examples of envisioned usage scenarios for IMT beyond 2020 (see for example ITU-R M.2083 Figure 2).

[0416] URLLC use cases have stringent requirements for performance such as throughput, latency, and availability. URLLC use cases are envisioned as one of the enabling technologies for future applications such as wireless control of industrial production or manufacturing processes, remote medical surgery, automation of power transmission and distribution in smart grids, and road safety. URLLC's ultra-high reliability is supported by identifying technologies that meet the requirements set by TR 38.913. Key requirements for NR URLLC in Release 15 include a target user plane latency of 0.5 ms on the UL (uplink) and 0.5 ms on the DL (downlink). The overall URLLC requirement for a single packet transmission is a block error rate (BLER) of 1E-5 for a packet size of 32 bytes with a user plane latency of 1 ms.

[0417] From a physical layer perspective, reliability can be improved in many possible ways. Current room for reliability improvement includes defining a separate CQI table for URLLC, more compact DCI formats, PDCCH repetition, etc. However, this room can be expanded to achieve ultra-high reliability as NR (with respect to the key requirements of NR URLLC) becomes more stable and more developed. Specific use cases for NR URLLC in Release 15 include augmented reality / virtual reality (AR / VR), e-health, e-safety, and mission-critical applications.

[0418] Also, technology enhancements targeted by NR URLLC aim at improving latency and improving reliability. Technology enhancements for improving latency include configurable numerology, non-slot-based scheduling with flexible mapping, grant-free (configured grant) uplink, slot-level repetition in data channel, and pre-emption in downlink. Pre-emption means that a transmission with already allocated resources is stopped and the already allocated resources are used for other transmissions with lower latency / higher priority requirements that are requested later. Thus, a transmission that was already allowed is preempted by a later transmission. Pre-emption is applicable regardless of the specific service type. For example, a transmission of service type A (URLLC) may be preempted by a transmission of service type B (eMBB, etc.). Technology enhancements for improving reliability include dedicated CQI / MCS tables for a target BLER of 1E-5.

[0419] The use case of mMTC (massive machine type communication) is characterized by a very large number of connected devices transmitting relatively small amounts of data that are typically not sensitive to delays. The devices are required to be low-cost and have a very long battery life. From an NR perspective, the use of very narrow bandwidth portions is one solution that allows UEs to save power and extend battery life.

[0420] As mentioned above, the scope of reliability improvement in NR is expected to be broader. One of the key requirements for all cases, e.g. for URLLC and mMTC, is high or ultra-high reliability. Several mechanisms can improve reliability from a radio perspective and a network perspective. In general, there are two to three key areas that can help improve reliability. These areas include compact control channel information, data channel / control channel repetition, and diversity with respect to frequency, time, and / or spatial domains. These areas are generally applicable to reliability improvement regardless of the specific communication scenario.

[0421] Further use cases with more stringent requirements are envisaged for NR URLLC, such as factory automation, transportation and power distribution, such as high reliability (up to 10-6 level of reliability), high availability, packet size up to 256 bytes, time synchronization up to a few μs (depending on the use case, the value can be 1 μs or a few μs depending on the frequency range and low latency in the order of 0.5 ms to 1 ms (e.g. 0.5 ms latency in the targeted user plane)).

[0422] Furthermore, for NR URLLC, several technical enhancements may be available from the perspective of the physical layer. These technical enhancements include enhancements to the PDCCH (Physical Downlink Control Channel) related to compact DCI, repetition of the PDCCH, and increased monitoring of the PDCCH. Also, the enhancement of UCI (Uplink Control Information) is related to the enhancement of enhanced HARQ (Hybrid Automatic Repeat Request) and CSI feedback. In addition, there may be enhancements to the PUSCH related to mini-slot level hopping, and enhancements to retransmission / repetition. The term "mini-slot" refers to a Transmission Time Interval (TTI) that contains fewer symbols than a slot (a slot has 14 symbols).

[0423] <QoS Control> The QoS (Quality of Service) model of 5G is based on QoS flows, and supports both QoS flows that require a guaranteed flow bit rate (GBR: Guaranteed Bit Rate QoS flow) and QoS flows that do not require a guaranteed flow bit rate (non-GBR QoS flow). Therefore, at the NAS level, a QoS flow is the finest-grained QoS classification in a PDU session. A QoS flow is identified within a PDU session by a QoS Flow ID (QFI: QoS Flow ID) that is carried in an encapsulation header via the NG-U interface.

[0424] For each UE, the 5GC establishes one or more PDU sessions. For each UE, the NG-RAN establishes at least one Data Radio Bearer (DRB) for the PDU session, e.g. as shown above with reference to Figure 31. Additional DRBs for the QoS flows of that PDU session can be configured later (when it is up to the NG-RAN). The NG-RAN maps packets belonging to different PDU sessions to different DRBs. The NAS level packet filters in the UE and 5GC associate UL and DL packets with QoS flows, whereas the AS level mapping rules in the UE and NG-RAN associate UL and DL QoS flows with DRBs.

[0425] Figure 33 shows the non-roaming reference architecture for 5G NR (see TS 23.501 v16.1.0, section 4.23). An Application Function (AF) (e.g., an external application server hosting 5G services as illustrated in Figure 32) interacts with the 3GPP core network to provide services. For example, it may access a Network Exposure Function (NEF) to support applications that affect traffic routing, or it may interact with a policy framework for policy control (e.g., QoS control) (see Policy Control Function (PCF)). Based on the operator's deployment, an Application Function that is considered trusted by the operator may interact directly with the relevant Network Function. An Application Function that is not allowed by the operator to directly access a Network Function interacts with the relevant Network Function using an exposure framework for the outside world via the NEF.

[0426] Figure 33 further illustrates further functional units of the 5G architecture: Network Slice Selection Function (NSSF), Network Repository Function (NRF), Unified Data Management (UDM), Authentication Server Function (AUSF), Access and Mobility Management Function (AMF), Session Management Function (SMF), and Data Network (DN, e.g., operator-provided services, Internet access, or third-party services). All or part of the core network functions and application services may be deployed and run in a cloud computing environment.

[0427] Therefore, the present disclosure provides an application server (e.g., an AF in a 5G architecture) comprising: a transmitter that, when operated, sends a request including QoS requirements for at least one of a URLLC service, an eMMB service, and an mMTC service to at least one of the 5GC functions (e.g., NEF, AMF, SMF, PCF, UPF, etc.) to establish a PDU session including a radio bearer between a gNodeB and a UE according to the QoS requirements; and a control circuit that, when operated, performs a service using the established PDU session.

[0428] The present disclosure can be realized by software, hardware, or software in cooperation with hardware. Each functional block used in the description of the above embodiment may be realized partially or entirely as an LSI, which is an integrated circuit, and each process described in the above embodiment may be controlled partially or entirely by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip so as to include some or all of the functional blocks. The LSI may have input and output of data. Depending on the degree of integration, the LSI may be called an IC, a system LSI, a super LSI, or an ultra LSI.

[0429] The method of integration is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, after LSI manufacturing, a programmable FPGA (Field Programmable Gate Array) or a reconfigurable processor that can reconfigure the connections and settings of circuit cells inside the LSI may be used. The present disclosure may be realized as digital processing or analog processing.

[0430] Furthermore, if a new integrated circuit technology that can replace LSI appears due to the progress of semiconductor technology or a derivative technology, it is possible to integrate the functional blocks using that technology. The application of biotechnology is also a possibility.

[0431] The present disclosure may be implemented in any type of apparatus, device, or system having a communication function (collectively referred to as a communication apparatus). The communication apparatus may include a radio transceiver and processing / control circuitry. The radio transceiver may include a receiver and a transmitter, or both as 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, etc.), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks, etc.), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smart watches, tracking devices, etc.), game consoles, digital book readers, telehealth and telemedicine devices, communication-enabled vehicles or mobile conveyances (e.g., cars, airplanes, boats, etc.), and combinations of the above devices.

[0432] Communications Equipment includes, but is not limited to portable or mobile equipment, non-portable or fixed equipment, devices and systems of any kind, such as smart home devices (appliances, lighting equipment, smart meters or metering devices, control panels, etc.), vending machines and any other "Things" that may exist on an Internet of Things (IoT) network.

[0433] Communications include data communications via cellular systems, wireless LAN systems, communications satellite systems, etc., as well as data communications via combinations of these.

[0434] 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.

[0435] 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.

[0436] A terminal according to an embodiment of the present disclosure includes a control circuit that controls communication in units of second symbols, each of which corresponds to a plurality of first symbols, and a communication circuit that performs the communication.

[0437] In one embodiment of the present disclosure, the control circuit controls the communication in units of time intervals constituted by a plurality of the second symbols.

[0438] In one embodiment of the present disclosure, the plurality of first symbols are consecutive symbols.

[0439] In one embodiment of the present disclosure, a signal is repeated in the first plurality of symbols.

[0440] In one embodiment of the present disclosure, the number of the second symbols constituting the time interval is equal to the number of the first symbols constituting the slot.

[0441] In one embodiment of the present disclosure, the signal processing device further includes a receiving circuit for receiving information regarding the number of the first symbols that constitute the second symbol.

[0442] In one embodiment of the present disclosure, the information about the number of first symbols indicates one of a plurality of candidate symbol numbers.

[0443] In one embodiment of the present disclosure, the information regarding the number of the first symbols is set for at least one of a downlink and an uplink.

[0444] In one embodiment of the present disclosure, the information regarding the number of the first symbols is set for the terminal for each channel or signal used for the communication.

[0445] In one embodiment of the present disclosure, information regarding the number of the first symbols is set for each parameter setting for the terminal.

[0446] In one embodiment of the present disclosure, the number of the first symbols that constitute the second symbol is a power of two.

[0447] In one embodiment of the present disclosure, the number of the first symbols constituting the second symbol is set based on the number of the first symbols constituting a slot.

[0448] In one embodiment of the present disclosure, the number of the first symbols constituting each of the at least two second symbols included in the time period is different from each other.

[0449] In an embodiment of the present disclosure, an upper limit value of the number of the first symbols constituting the second symbol is less than the number of the first symbols constituting a slot.

[0450] In one embodiment of the present disclosure, the second time interval starts at the beginning of the slot.

[0451] In one embodiment of the present disclosure, the second time interval starts from any symbol position within the slot.

[0452] In one embodiment of the present disclosure, the control circuitry determines time domain resources for the communication based on the second symbol and the time interval.

[0453] In one embodiment of the present disclosure, the control circuitry determines a time domain resource for the communication based on the second symbol, the time interval, the first symbol, and a slot.

[0454] In one embodiment of the present disclosure, the control circuitry determines a time domain resource for the communication based on the second symbol, the time interval, and an offset relative to the first symbol.

[0455] In one embodiment of the present disclosure, the control circuit determines an allocation of a reference signal used in the communication to a time domain resource based on the second symbol and the time interval.

[0456] In one embodiment of the present disclosure, the control circuit determines an allocation of a reference signal used in the communication to a time domain resource based on the second symbol, the time interval, and the slot.

[0457] In one embodiment of the present disclosure, the control circuit controls repetition in the communication based on either the time interval or a unit of a plurality of the second symbols.

[0458] In an embodiment of the present disclosure, the unit of the plurality of second symbols is a unit of resources allocated to a signal in units of the second symbols.

[0459] In a communication method according to an embodiment of the present disclosure, a terminal controls communication in units of second symbols, each second symbol being associated with a plurality of first symbols, and performs the communication.

[0460] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2020-028050, filed on February 21, 2020, are incorporated herein by reference in their entirety. [Industrial Applicability]

[0461] One embodiment of the present disclosure is useful in wireless communication systems. [Explanation of symbols]

[0462] 100 base stations 101,205 Control section 102 Upper control signal generation unit 103 Downlink control information generator 104,206 Encoding section 105,207 Modulation section 106,208 Signal Allocation Section 107,209 Transmitter 108,201 Receiver 109,202 Extraction part 110,203 Demodulation section 111,204 Decoding section 200 terminals< / option>

Claims

1. a control circuit that controls communication in units of second symbols, each of which corresponds to a plurality of first symbols; A communication circuit for performing the communication; a receiving circuit for receiving information regarding the number of the first symbols constituting the second symbol; Equipped with The information regarding the number of the first symbols is set for the terminal for each channel or signal used in the communication, or is set for each parameter setting for the terminal. Terminal.

2. the control circuit controls the communication in units of a time interval constituted by a plurality of the second symbols. The terminal according to claim 1.

3. the plurality of first symbols are consecutive symbols; The terminal according to claim 1.

4. A signal is repeated in the plurality of first symbols. The terminal according to claim 1.

5. the number of the second symbols constituting the time interval is equal to the number of the first symbols constituting a slot; The terminal according to claim 2.

6. The information regarding the number of the first symbols indicates one of a plurality of candidate symbol numbers. The terminal according to claim 1.

7. The information regarding the number of the first symbols is set for at least one of a downlink and an uplink. The terminal according to claim 1.

8. the number of the first symbols constituting the second symbol is a power of 2; The terminal according to claim 1.

9. the number of the first symbols constituting the second symbol is set based on the number of the first symbols constituting a slot. The terminal according to claim 1.

10. the number of the first symbols constituting each of at least two of the second symbols included in the time period is different from each other; The terminal according to claim 2.

11. an upper limit of the number of the first symbols constituting the second symbol is less than the number of the first symbols constituting a slot; The terminal according to claim 1.

12. The terminal is Controlling communication in units of second symbols, each of which corresponds to a plurality of first symbols; Performing said communication; receiving information regarding the number of the first symbols that constitute the second symbol; The information regarding the number of the first symbols is set for the terminal for each channel or signal used in the communication, or is set for each parameter setting for the terminal. Communication methods.

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