Terminal, wireless communication method, base station, and system

Abstract

One embodiment of the terminal disclosed herein comprises: a receiving unit for receiving a response signal corresponding to a random access preamble code transmitted based on a downlink control channel; and a control unit for controlling, when transmitting an uplink shared channel based on the response signal, the presence or absence of a phase tracking reference signal (PTRS) in an initial transmission and the presence or absence of a PTRS in a retransmission are shared.

Description

Technical Field

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

[0002] In the Universal Mobile Telecommunications System (UMTS) network, Long Term Evolution (LTE) has been standardized to achieve even higher data rates and lower latency (Non-Patent Document 1). Furthermore, LTE-Advanced (3GPP Rel. 10-14) has been standardized to further enhance the capacity and sophistication of LTE (Third Generation Partnership Project (3GPP) Releases (Rel.) 8 and 9).

[0003] Successor systems to LTE (for example, also referred to as 5th generation mobile communication system (5G), 5G+ (plus), New Radio (NR), 3GPP Rel. 15 and later, etc.) are also under study.

[0004] In existing LTE systems (e.g., 3GPP Rel. 8-14), user terminals (UEs) control the reception of downlink shared channels (e.g., the Physical Downlink Shared Channel (PDSCH)) based on downlink control information (also known as Downlink Control Information (DCI), DL assignments, etc.) from the base station. Furthermore, user terminals control the transmission of uplink shared channels (e.g., the Physical Uplink Shared Channel (PUSCH)) based on DCI (also known as UL grants, etc.).

[0005] Prior art literature

[0006] Non-patent literature

[0007] Non-Patent Document 1: 3GPP TS 36.300 V8.12.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8)”, April 2010 Summary of the Invention

[0008] Problems to be solved by the invention

[0009] In future wireless communication systems (e.g., NR), research is underway to transmit Phase Tracking Reference Signals (PTRS) in both the UL and DL. For example, when a UE transmits an uplink shared channel (e.g., PUSCH), the PTRS is controlled based on settings from the network (e.g., the base station).

[0010] In addition, in NR, the random access procedure is supported. During the random access procedure, when the UE includes an UL transmission instruction (e.g., UL grant) in the response signal sent to the random access preamble, the UE transmits the PUSCH based on the UL grant. In addition, in the event of a PUSCH transmission failure, it is also envisaged to retransmit the PUSCH. However, how to control the transmission of PTRS in this case has not been fully studied.

[0011] Therefore, one of the objects of the present disclosure is to provide a terminal and a wireless communication method that can appropriately transmit a Phase Tracking Reference Signal (PTRS).

[0012] A terminal according to one embodiment of the present invention is characterized in that it comprises: a receiving unit for receiving a response signal corresponding to a random access preamble code transmitted based on a downlink control channel; and a control unit for controlling, when transmitting an uplink shared channel based on the response signal, the presence or absence of a phase tracking reference signal (PTRS) in an initial transmission and the presence or absence of a PTRS in a retransmission are made common.

[0013] Effects of the Invention

[0014] According to one embodiment of the present disclosure, a phase tracking reference signal (PTRS) can be appropriately transmitted. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a diagram showing an example of a contention-based random access procedure.

[0016] Figure 2 This is a diagram showing an example of a non-contention-based random access procedure.

[0017] Figure 3 This is a diagram showing an example of RAR notified through MAC CE.

[0018] Figure 4A as well as Figure 4B This is a diagram showing an example of PUSCH transmission control according to the first method.

[0019] Figure 5A as well as Figure 5B This is a diagram showing another example of PUSCH transmission control according to the second method.

[0020] Figure 6 This is a diagram showing an example of an MCS table.

[0021] Figure 7 This is a diagram showing an example of a two-step random access procedure.

[0022] Figure 8 This is a diagram showing another example of a two-step random access procedure.

[0023] Figure 9 This is a diagram showing an example of a schematic configuration of a wireless communication system according to one embodiment.

[0024] Figure 10 This is a diagram showing an example of the configuration of a base station according to one embodiment.

[0025] Figure 11 This is a diagram showing an example of the configuration of a user terminal according to one embodiment.

[0026] Figure 12 This is a diagram showing an example of the hardware configuration of a base station and a user terminal according to one embodiment. DETAILED DESCRIPTION

[0027] <Random Access Procedure>

[0028] In existing LTE systems (e.g., LTE Rel. 8-13), random access procedures for establishing UL synchronization are supported. These procedures include contention-based random access (also known as contention-based random access (CBRA)) and non-contention-based random access (also known as non-CBRA or contention-free random access (CFRA)).

[0029] In contention-based random access (CBRA), a terminal (hereinafter also referred to as a user terminal or UE) transmits a preamble randomly selected from multiple preambles (random access preamble, random access channel (Physical Random Access Channel (PRACH)), RACH preamble, etc.) determined for each cell. Contention-based random access is a UE-led random access procedure and can be used, for example, for initial access, starting or resuming UL transmission, etc.

[0030] On the other hand, in non-contention-based random access (Non-CBRA, CFRA), the base station allocates a preamble to a specific UE via the downlink (DL) control channel (PDCCH), and the UE transmits the preamble allocated by the base station. Non-contention-based random access is a network-led random access procedure and can be used, for example, during handovers and when starting or resuming DL transmission (when starting or resuming UL transmission of retransmission indication information for DL).

[0031] Figure 1 This is a diagram showing an example of contention-based random access. Figure 1 In the present invention, the UE receives information (PRACH structure information) indicating the structure (PRACH configuration, RACH configuration) of the random access channel (PRACH) in advance through system information (e.g., MIB (Master Information Block) and / or SIB (System Information Block)) or higher-layer signaling (e.g., RRC (Radio Resource Control) signaling).

[0032] The PRACH structure information can, for example, represent: multiple preamble codes determined for each cell (such as the preamble code format), time resources used in PRACH transmission (such as the system frame number, subframe number), and frequency resources (such as the offset (frequency offset (prach-Frequency Offset)) of the starting position of 6 resource blocks (physical resource blocks (PRB: Physical Resource Block))).

[0033] like Figure 1As shown, when the UE migrates from the idle (RRC_IDLE) state to the RRC connected (RRC_CONNECTED) state (for example, at the time of initial access), or when it is in the RRC connected state but UL synchronization is not established (for example, when UL transmission is started or restarted), the UE randomly selects one of the multiple preamble codes represented by the PRACH structure information, and sends the selected preamble code (message 1) through the PRACH.

[0034] When the base station detects the preamble, it responds with a Random Access Response (RAR) (Message 2). After transmitting the preamble, if the UE fails to receive the RAR within a specific period (RAR window), it increases the PRACH transmit power and retransmits (retransmits) the preamble. Increasing the transmit power during retransmission is also called power ramping.

[0035] The UE that receives the RAR adjusts the UL transmission timing based on the timing advance (TA) included in the RAR and establishes UL synchronization. In addition, the UE sends a high-level (Layer 2 / Layer 3 (L2 / L3: Layer2 / Layer3)) control message (message 3) in the UL resources specified by the UL grant included in the RAR. The control message contains the UE identifier (UE-ID). The UE identifier can be, for example, a C-RNTI (Cell-RadioNetwork Temporary Identifier) ​​if it is in the RRC connected state, or a high-level UE-ID such as an S-TMSI (System Architecture Evolution-Temporary Mobile Subscriber Identity) if it is in the idle state.

[0036] The base station transmits a contention resolution message (Message 4) based on a control message from a higher layer. This contention resolution message is transmitted based on the UE identifier address included in the control message. A UE that successfully detects the contention resolution message transmits a positive response (ACK) in a HARQ (Hybrid Automatic Repeat reQuest) to the base station. This causes the UE in the idle state to transition to the RRC connected state.

[0037] On the other hand, a UE that fails to detect the contention resolution message determines that contention has occurred, selects a preamble again, and repeats the random access procedure of messages 1 to 4. Upon detecting that the contention has been resolved through an ACK from the UE, the base station transmits a UL grant to the UE. The UE begins UL data transmission using the UL resources allocated by the UL grant.

[0038] Figure 2 This figure shows an example of non-contention-based random access. In the case of non-contention-based random access, the base station first transmits a physical downlink control channel (PDCCH indication (PDCCH-order)) to the UE to instruct it to send a PRACH (Message 0). The UE transmits a random access preamble (PRACH) at the timing indicated by the PDCCH (Message 1). Upon detecting the random access preamble, the base station transmits a random access response (RAR) as its response information (Message 2).

[0039] The UE completes the non-contention-based random access process upon receiving Message 2. Similar to contention-based random access, if reception of Message 2 fails, the PRACH transmit power is increased and Message 1 is retransmitted. Upon receiving Message 2, the UE may also transmit UL data (e.g., PUSCH) based on the UL transmission instruction (UL grant) included in Message 2.

[0040] In the contention-based random access procedure and the non-contention-based random access procedure, the random access response (RAR) may also include information for instructing UL transmission (such as UL grant) (see Figure 3 ). Figure 3 An example of MAC control information (MAC RAR) corresponding to RAR is shown. The UE transmits the uplink shared channel (PUSCH) based on the timing advance command, UL grant, etc. included in the RAR.

[0041] In a contention-based random access procedure, a PUSCH equivalent to Message 3 is transmitted based on the UL grant included in the RAR. In a non-contention-based random access procedure, a PUSCH is transmitted based on the UL grant included in the RAR. This PUSCH may also include power headroom information, buffer status reports, etc.

[0042] <ptrs>

[0043] In NR, a base station (e.g., a gNB) transmits a Phase Tracking Reference Signal (PTRS) in the downlink. The base station may also map the PTRS continuously or discontinuously in time to a single subcarrier and transmit it. The base station may also transmit the PTRS during at least a portion of the time period (time slot, symbol, etc.) during which the downlink shared channel (PDSCH) is transmitted. The PTRS transmitted by the base station is also referred to as the DL PTRS.

[0044] In addition, the UE transmits a Phase Tracking Reference Signal (PTRS) in the uplink. The UE may also transmit the PTRS by mapping it continuously or discontinuously in the time direction, for example, on one subcarrier. The UE may also transmit the PTRS during at least a portion of the period (time slot, symbol, etc.) during which the uplink shared channel (Physical Uplink Shared Channel (PUSCH)) is transmitted. The PTRS transmitted by the UE may also be referred to as the UL PTRS. Hereinafter, the UL PTRS will be referred to as PTRS.

[0045] The UE may also determine whether PTRS exists in the uplink (e.g., whether PTRS is being transmitted) based on the settings of higher-layer signaling (e.g., PTRS-UplinkConfig). If higher-layer signaling related to PTRS (e.g., PTRS-UplinkConfig) is configured, the UE may also assume that PTRS exists in the resource blocks used for PUSCH transmission. The base station may also determine phase noise based on the PTRS transmitted from the UE and correct the phase error of the received signal.

[0046] Here, the higher layer signaling may be, for example, RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling, broadcast information, or a combination thereof.

[0047] MAC signaling may use, for example, MAC control elements (MAC CEs) and MAC protocol data units (MAC PDUs). Broadcast information may include, for example, a master information block (MIB), a system information block (SIB), minimum system information (RMSI), and other system information (OSI).

[0048] When the UE transmits PTRS while transmitting PUSCH, the UE may perform control (eg, rate matching) so that the resources mapped with PTRS are not used for PUSCH transmission.

[0049] In addition, even when PTRS-related high-layer signaling (e.g., PTRS-UplinkConfig) is set, the transmission of PTRS can be controlled based on the type or category of RNTI used for downlink control information (e.g., UL grant). For example, when the RNTI used in downlink control information (or DCI CRC scrambling) is MCS-C-RNTI, C-RNTI, CS-RNTI, or SP-CSI-RNTI, PTRS can also be present in PUSCH.

[0050] In this case, the UL grant included in the RAR (RAR UL grant) is not included in the above-mentioned RNTI type because RA-RNTI is applied. Therefore, the PUSCH scheduled by the RAR UL grant (RAR UL grant) basically does not include (does not exist) PTRS.

[0051] On the other hand, when the base station fails to receive (e.g., decode) the PUSCH scheduled in the RAR UL grant, the base station triggers or instructs retransmission of the PUSCH. For example, in non-contention-based random access, it is also considered to use DCI scrambled by CRC using C-RNTI to schedule retransmission.

[0052] At this time, if PTRS is configured via higher-layer signaling (e.g., PTRS-UplinkConfig), it is assumed that PTRS is present in PUSCH retransmissions (e.g., the UE also transmits PTRS when transmitting PUSCH). If PTRS is not present in the initial PUSCH transmission (initial transmission), there is a concern that the transport block size may not be the same in the initial PUSCH transmission and the retransmission.

[0053] The inventors of the present invention have studied how to control the transmission (or mapping) of the PTRS in at least one of the initial transmission of the PUSCH transmitted based on the RAR UL grant and the retransmission of the PUSCH, thereby completing the present invention.

[0054] The following describes the embodiments of the present disclosure in detail with reference to the accompanying drawings. Furthermore, the first to fourth embodiments described below may be used individually or in combination. In the following description, the presence or absence of PTRS transmission and the presence or absence of PTRS may be interchanged.

[0055] In the following description, the presence or absence of PTRS transmission during PUSCH transmission, which is instructed to be transmitted in the RAR UL grant in the non-contention-based (CFRA) random access procedure, is used as an example, but the present invention is not limited to this. It can also be applied to PTRS transmission during PUSCH transmission, which is instructed to be transmitted in the RAR UL grant in the contention-based (CBRA) random access procedure. Alternatively, it can also be applied to PTRS during initial and retransmission of PUSCHs other than random access procedures (e.g., PUSCHs based on configured grants).

[0056] In this specification, retransmission (or retransmission) may refer to only the first retransmission after the initial transmission, or may refer to multiple retransmissions (multiple retransmissions transferred from the first retransmission).

[0057] (First Method)

[0058] In the first method, when an uplink shared channel (e.g., PUSCH) is transmitted based on a random access response (e.g., RAR), the presence or absence of PTRS in the PUSCH is controlled so that the presence or absence of PTRS in the PUSCH is common to the initial transmission of the PUSCH and the retransmission of the PUSCH.

[0059] That is, when the UE transmits (or maps) PTRS in the PUSCH of initial transmission, it also transmits PTRS in the PUSCH of retransmission (refer to Figure 4A On the other hand, the UE can also control the PTRS not to be sent (or mapped) in the first transmitted PUSCH and not to be sent in the retransmitted PUSCH (refer to Figure 4B ).

[0060] For example, the UE may also control the transmission of the PTRS in the PUSCH using at least one of the following options 1-1 to 1-3.

[0061] <Option 1-1>

[0062] The UE controls so that the PTRS is not transmitted (or mapped) in the initial transmission of the PUSCH and the PTRS is not transmitted in the retransmission of the PUSCH (refer to Figure 4A ). When PTRS is set through higher-layer signaling, the UE may ignore the setting of the higher-layer signaling and control not to send PTRS.

[0063] By transmitting the PTRS in the initial transmission and retransmission of the PUSCH, it is easy to control the transport block size (TBS) of the initial transmission and the retransmission to be the same.

[0064] <Options 1-2>

[0065] The UE controls so that the PTRS is transmitted (or mapped) in the initial transmission of the PUSCH and the PTRS is transmitted in the retransmission of the PUSCH (refer to Figure 4A ).

[0066] Option 1-2 may be applied when PTRS is configured by higher layer signaling (eg, UE-specific parameters). Option 1-1 may be applied even when PTRS is not configured by higher layer signaling.

[0067] Alternatively, even when PTRS is not configured by higher layer signaling, options 1 and 2 may be applied. In this case, the UE may transmit PTRS regardless of whether or not PTRS is configured by higher layer signaling.

[0068] Alternatively, the PTRS corresponding to the initial transmission and the PTRS corresponding to the retransmission may be set in different higher-layer signalings. In this case, if the PTRS corresponding to the initial transmission is set, options 1-2 may be applied regardless of whether the PTRS corresponding to the retransmission is set (for example, even if the PTRS is not set).

[0069] By transmitting the PTRS during the initial and retransmission of the PUSCH, it is easier to control the transport block size of the initial and retransmissions to be the same. In addition, the base station determines the phase noise based on the PTRS sent from the UE during both the initial and retransmissions, and can appropriately correct the phase error of the received signal.

[0070] <Options 1-3>

[0071] Regardless of whether or not PTRS is configured based on higher-layer signaling (UE-specific parameters), the UE may also perform control so that PTRS is transmitted (or mapped) during initial transmission and retransmission of the PUSCH.

[0072] In this case, the UE may also apply a specific value (eg, a default value) as a parameter of the PTRS structure to transmit the PTRS. The parameter of the PTRS structure may also be at least one of time density and frequency density.

[0073] For example, when a higher-layer parameter related to time density (timeDensity) is not notified, or when a timeDensity field does not exist, the UE may apply a specific time density (e.g., L_PT-RS = 1). Alternatively, when a higher-layer parameter related to frequency density (frequencyDensity) is not notified, or when a frequencyDensity field does not exist, the UE may apply a specific frequency density (e.g., K_PT-RS = 2).

[0074] The UE may apply the parameters of a specific PTRS structure only when the PTRS is not configured in the higher-layer signaling, or may apply the parameters of the specific PTRS structure even when the PTRS is configured in the higher-layer signaling.

[0075] In this way, by controlling the transmission of PTRS in initial transmission and retransmission of PUSCH regardless of whether PTRS is configured based on higher layer parameters, it is possible to appropriately control the transmission of PTRS in PUSCH scheduled in RAR UL grant.

[0076] <Changes>

[0077] The UE may also decide whether to include the PTRS in the retransmission based on whether the PTRS was included in the initial transmission (or the previous retransmission), regardless of whether the PTRS is configured based on higher layer signaling or the RNTI type.

[0078] (Second Method)

[0079] In the second example, when uplink shared channel transmission is performed based on a random access response, the presence or absence of PTRS in the PUSCH is controlled separately (eg, differently) for initial PUSCH transmission and retransmission of the PUSCH.

[0080] That is, the UE independently controls the transmission (or mapping) of the PTRS in the PUSCH transmission of the initial transmission (initial transmission) and the transmission of the PTRS in the PUSCH transmission of the retransmission (re-transmission).

[0081] For example, the UE may also control the transmission of the PTRS in the PUSCH using at least one of the following options 2-1 to 2-4.

[0082] <Option 2-1>

[0083] The UE controls not to transmit (or map) the PTRS in the initial transmission of the PUSCH. The UE may also control not to transmit the PTRS regardless of whether the PTRS is configured by higher layer signaling.

[0084] On the other hand, in the retransmission of PUSCH, the transmission of PTRS can also be controlled according to the setting of PTRS based on the upper layer signaling. For example, when PTRS is set by the upper layer signaling, control is performed so that PTRS is transmitted in the retransmission of PUSCH (refer to Figure 5A ).

[0085] Alternatively, even if PTRS is not configured by higher layer signaling, the UE may be controlled to transmit PTRS during PUSCH retransmission. In this case, the UE may transmit PTRS while ignoring the non-configuration of PTRS based on higher layer signaling.

[0086] By not transmitting PTRS during the initial PUSCH transmission and transmitting PTRS during PUSCH retransmissions, phase noise correction can be appropriately performed using PTRS during PUSCH retransmissions. This can lead to a reduction in the error rate of PUSCH retransmissions.

[0087] <Option 2-2>

[0088] The UE may also control whether to transmit PTRS during initial PUSCH transmission based on whether PTRS is configured by higher layer signaling. For example, if PTRS is configured by higher layer signaling, the UE may control PTRS transmission during retransmission of PUSCH.

[0089] On the other hand, it is also possible to control the retransmission of PUSCH regardless of whether the PTRS is set based on the higher layer signaling so that the PTRS is not transmitted (see Figure 5B For example, when PTRS is configured through higher-layer signaling, the UE may be controlled so as to ignore the presence or absence of the higher-layer signaling configuration and not transmit PTRS.

[0090] In this way, by setting a configuration in which PTRS is transmitted during the initial PUSCH transmission and PTRS is not transmitted during PUSCH retransmission, the error rate of the retransmitted PUSCH can be reduced when the data coding rate is lowered compared to the initial transmission. On the other hand, when the data coding rate is equal to that of the initial transmission during retransmission, the resources used for the retransmission of the PUSCH can be reduced compared to the initial transmission, and the frequency utilization efficiency of the retransmission of the PUSCH can be expected to be improved.

[0091] <Options 2-3>

[0092] The UE may separately control whether or not to transmit PTRS in the initial transmission of PUSCH and whether or not to transmit PTRS in the retransmission of PUSCH, regardless of whether or not PTRS is configured based on higher-layer signaling (UE-specific parameters).

[0093] For example, regardless of whether or not PTRS is configured based on higher-layer signaling (UE-specific parameters), the UE may perform control such that PTRS is transmitted during initial PUSCH transmission and PTRS is not transmitted during retransmission of PUSCH.

[0094] The parameters of the PTRS structure applied to the transmission of the PTRS in the initial transmission of the PUSCH may also be applied with specific values ​​(eg, default values). The parameters of the PTRS structure applied to the PTRS transmission may also be applied with the methods shown in the above options 1-3.

[0095] <Options 2-4>

[0096] The UE may separately control whether or not to transmit PTRS in the initial transmission of PUSCH and whether or not to transmit PTRS in the retransmission of PUSCH, regardless of whether or not PTRS is configured based on higher layer signaling (UE-specific parameters).

[0097] For example, regardless of the presence or absence of PTRS configuration based on higher layer signaling (UE-specific parameters), the UE may perform control so that PTRS is not transmitted in the initial transmission of the PUSCH but is transmitted in the retransmission of the PUSCH.

[0098] Specific values ​​(eg, default values) may also be applied to the parameters of the PTRS structure applied to the transmission of the PTRS in the retransmission of the PUSCH. The methods shown in the above options 1-3 may also be applied to the parameters of the PTRS structure applied to the PTRS transmission.

[0099] In this way, regardless of whether PTRS is configured based on higher-layer parameters, by separately controlling whether PTRS is transmitted during initial and retransmissions of the PUSCH, it is possible to appropriately control the phase noise correction and error rate reduction effects of inserting PTRS, and the data coding rate reduction and PUSCH resource usage reduction effects of not inserting PTRS, respectively, during initial and retransmissions. As a result, it is possible to more flexibly and appropriately control improvements in network utilization efficiency and communication quality.

[0100] (Third Method)

[0101] In the third example, when transmitting an uplink shared channel based on a random access response, the UE autonomously determines (UE implements) whether or not PTRS is present in at least one of initial transmission of the PUSCH and retransmission of the PUSCH.

[0102] For example, the UE may also control the transmission of the PTRS in the PUSCH using at least one of the following options 3-1 to 3-5.

[0103] <Option 3-1>

[0104] The UE controls not to transmit (or map) the PTRS in the initial transmission of the PUSCH. The UE may also control not to transmit the PTRS regardless of whether the PTRS is configured by higher layer signaling.

[0105] On the other hand, the UE may autonomously decide whether to transmit the PTRS during PUSCH retransmission.

[0106] <Option 3-2>

[0107] The UE may also control whether to transmit PTRS during the initial PUSCH transmission based on whether PTRS is configured by higher layer signaling. For example, if PTRS is configured by higher layer signaling, the UE may control PTRS transmission during the initial PUSCH transmission.

[0108] On the other hand, the UE may autonomously determine (UE implementation) whether to transmit the PTRS during PUSCH retransmission.

[0109] <Option 3-3>

[0110] The UE may also autonomously decide whether to transmit the PTRS during the initial transmission of the PUSCH.

[0111] On the other hand, the UE controls not to transmit (or map) the PTRS in the retransmission of the PUSCH. The UE can control not to transmit the PTRS regardless of whether the PTRS is configured by higher layer signaling.

[0112] <Options 3-4>

[0113] The UE may also autonomously decide whether to transmit the PTRS during the initial transmission of the PUSCH.

[0114] On the other hand, the UE may also control whether to transmit PTRS during PUSCH retransmission based on whether PTRS is configured by higher layer signaling. For example, if PTRS is configured by higher layer signaling, control is performed so that PTRS is transmitted during PUSCH retransmission.

[0115] <Options 3-5>

[0116] The UE may autonomously determine whether to transmit the PTRS during the initial transmission of the PUSCH and the retransmission of the PUSCH.

[0117] In this way, by setting a configuration in which the UE autonomously determines whether to transmit the PTRS, even when there is no PTRS configuration instruction from the base station, PUSCH transmission based on the RAR UL grant can be appropriately performed.

[0118] (Fourth Method)

[0119] The fourth embodiment describes the transport block size (TBS) used for initial and retransmission of the PUSCH. The fourth embodiment is suitable for use in situations where PTRS transmission is used only for initial or retransmission (e.g., the second embodiment). Of course, the configurations applicable to the fourth embodiment are not limited to this.

[0120] In NR, based on a specific field (e.g., the modulation and coding scheme (MCS) field) included in the downlink control information (e.g., UL grant), at least one of the modulation mode (or modulation order) and coding rate of the PUSCH scheduled by the DCI is controlled.

[0121] Specifically, the UE is studying the use of a table (MCS table) that associates the MCS index, modulation order, and TBS index to determine the modulation order / coding rate corresponding to the MCS index indicated by the MCS field in the DCI for PUSCH.

[0122] Here, each modulation order is a value corresponding to each modulation method. For example, the modulation orders of QPSK (Quadrature Phase Shift Keying), 16QAM (Quadrature Amplitude Modulation), 64QAM, and 256QAM are 2, 4, 6, and 8, respectively.

[0123] Figure 6 This is a diagram showing an example of an MCS table. Figure 6 The values ​​of the MCS table shown are only examples and are not limited to these. MCS ) is associated with a part of the items (such as spectrum efficiency), and other items can also be added.

[0124] Figure 6 This section shows an example of a table used when transform precoding is activated and the MCS table information does not indicate 256QAM. Alternatively, separate tables may be defined for use when transform precoding is activated and for use when transform precoding is activated and the MCS table information indicates 256QAM.

[0125] UE can also use Figure 6 The table determines the modulation order / coding rate corresponding to the MCS index (IMCS) in the DCI. Figure 6 In the case where the UE meets certain conditions (for example, support for BPSK), the modulation order q corresponding to a specific MCS index (for example, 0, 1) can also be 1 (BPSK). If the above-mentioned specific conditions are not met, the modulation order q can also be 2 (QPSK).

[0126] In this way, the UE decides a modulation scheme to be applied to the PUSCH (initial transmission or retransmission) based on the MCS index included in the UL grant.

[0127] exist Figure 6 In the table, MCS indexes 28 to 31 correspond to reserved bits. In the fourth method, the reserved bits are used to notify the transport block length (TBS) applied to the PUSCH.

[0128] For example, when the MCS field included in the DCI (e.g., UL grant) instructing PUSCH retransmission indicates a specific MCS index, the UE applies the TBS applied in the initial transmission (or the previous retransmission) to the PUSCH retransmission. In other words, when one of the MCS indices 28-31 is specified by the MCS field, the UE controls the initial transmission and retransmission so that the TBS is the same.

[0129] Here, it is assumed that the specific MCS index is at least one of the MCS indices 28-31 equivalent to the reserved bits, but the value of the specific MCS index is not limited to this.

[0130] In this way, by specifying the TBS using bits in a specific field included in downlink control information indicating retransmission (e.g., UL grant), the TBS of each transmission can be made the same even when PTRS is included in only one of the initial transmission and retransmission of PUSCH.

[0131] (change)

[0132] In NR, research is underway to implement a random access procedure using fewer steps than the existing four. One example is a two-step random access procedure. This two-step random access procedure is also known as a two-step random access procedure, two-step RACH, or two-step RACH. The first to fourth methods described above can also be applied to a two-step RACH.

[0133] Figure 7 An example of a two-step RACH is shown. The two-step RACH may be composed of a first step in which a UE transmits to a base station, and a second step in which a base station transmits to a UE.

[0134] For example, in the first step, at least one of a UL signal and a UL channel (hereinafter referred to as UL signal / UL channel) including a preamble and a message may be transmitted from the UE to the base station. The preamble may have a structure that serves the same purpose as Message 1 (PRACH) in the conventional random access procedure. The message may have a structure that serves the same purpose as Message 3 (PUSCH) in the conventional random access procedure. Furthermore, the preamble and message transmitted in the first step may be referred to as Message A (Msg. A) or the first message.

[0135] Furthermore, in the second step, a DL signal and at least one of a DL channel (hereinafter referred to as a DL signal / DL channel) including a response and contention resolution may be transmitted from the base station to the UE. The response may have a structure that functions similarly to Message 2 (a random access response (RAR) transmitted via the PDSCH) in the conventional random access procedure. The contention resolution may have a structure that functions similarly to Message 4 (PDSCH) in the conventional random access procedure. The message transmitted in the second step may also be referred to as Message B (Msg. B) or a second message.

[0136] In the 2-step RACH, for example, it is assumed that the message in the first step (equivalent to the existing message 3) is transmitted using an uplink shared channel (eg, PUSCH) (see Figure 8 ). In such a case, at least one of the first to fourth methods described above may be applied to the initial transmission and retransmission of the PUSCH included in message A.

[0137] (Wireless Communication System)

[0138] The following describes the configuration of a wireless communication system according to an embodiment of the present disclosure. In this wireless communication system, communication is performed using any one or a combination of the wireless communication methods according to the above-described embodiments of the present disclosure.

[0139] Figure 9 This figure shows an example of a schematic configuration of a wireless communication system according to one embodiment. The wireless communication system 1 may also be a system that implements communication using Long Term Evolution (LTE) standardized by the Third Generation Partnership Project (3GPP) or the fifth generation mobile communication system New Radio (5G NR).

[0140] In addition, the wireless communication system 1 can also support dual connectivity (Multi-RAT Dual Connectivity (MR-DC)) between multiple radio access technologies (Radio Access Technology (RAT)). MR-DC can also include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

[0141] In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN), and the NR base station (gNB) is the secondary node (SN). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

[0142] The wireless communication system 1 can also support dual connectivity between multiple base stations within the same RAT (for example, dual connectivity (NR-NR Dual Connectivity (NN-DC)) where both MN and SN are NR base stations (gNB)).

[0143] The wireless communication system 1 may also include a base station 11 that forms a macrocell C1 with relatively wide coverage, and base stations 12 (12a-12c) that are located within the macrocell C1 and form small cells C2 that are narrower than the macrocell C1. User terminals 20 may also be located within at least one of the cells. The arrangement and number of cells and user terminals 20 are not limited to those shown in the figure. Hereinafter, when not distinguishing between base stations 11 and 12, they are collectively referred to as base stations 10.

[0144] The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CCs) and dual connectivity (DC).

[0145] Each CC may also be included in at least one of the first frequency band (Frequency Range 1 (FR1)) and the second frequency band (Frequency Range 2 (FR2)). The macro cell C1 may also be included in FR1, and the small cell C2 may also be included in FR2. For example, FR1 may be a frequency band below 6 GHz (sub-6 GHz), and FR2 may be a frequency band higher than 24 GHz (above-24 GHz). In addition, the frequency bands and definitions of FR1 and FR2 are not limited to this. For example, FR1 may also correspond to a frequency band higher than FR2.

[0146] Furthermore, the user terminal 20 may communicate in each CC using at least one of time division duplex (TDD) and frequency division duplex (FDD).

[0147] Multiple base stations 10 can also be connected by wired (for example, optical fiber based on Common Public Radio Interface (CPRI)), X2 interface, etc.) or wireless (for example, NR communication). For example, when NR communication is used as a backhaul between base stations 11 and 12, the base station 11 equivalent to the upper station can also be called an integrated access backhaul (IAB) donor, and the base station 12 equivalent to the relay station can also be called an IAB node.

[0148] The base station 10 may also be connected to the core network 30 via other base stations 10 or directly. The core network 30 may also include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), and a Next Generation Core (NGC).

[0149] The user terminal 20 may also be a terminal that supports at least one of communication methods such as LTE, LTE-A, and 5G.

[0150] In the wireless communication system 1, a radio access scheme based on orthogonal frequency division multiplexing (OFDM) may be used. For example, in at least one of the downlink (DL) and uplink (UL), cyclic prefix OFDM (CP-OFDM), discrete Fourier transform spread OFDM (DFT-s-OFDM), orthogonal frequency division multiple access (OFDMA), or single carrier frequency division multiple access (SC-FDMA) may be used.

[0151] The radio access scheme may also be referred to as a waveform. In addition, in the wireless communication system 1, other radio access schemes (for example, other single-carrier transmission schemes, other multi-carrier transmission schemes) may be applied to the UL and DL radio access schemes.

[0152] In the wireless communication system 1, as downlink channels, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH))), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. can also be used.

[0153] In addition, in the wireless communication system 1, as uplink channels, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), etc. can also be used.

[0154] The PDSCH is used to transmit user data, higher-layer control information, and system information blocks (SIBs). The PUSCH can also be used to transmit user data, higher-layer control information, and the PBCH can also be used to transmit master information blocks (MIBs).

[0155] The lower layer control information may also be transmitted via the PDCCH. The lower layer control information may include, for example, downlink control information (Downlink Control Information (DCI)) including scheduling information for at least one of the PDSCH and the PUSCH.

[0156] In addition, the DCI that schedules the PDSCH may also be referred to as DL allocation, DL DCI, etc., and the DCI that schedules the PUSCH may also be referred to as UL grant, UL DCI, etc. In addition, the PDSCH may also be interpreted as DL data, and the PUSCH may also be interpreted as UL data.

[0157] In PDCCH detection, a control resource set (CORESET) and a search space can also be used. A CORESET corresponds to the resources for searching for DCI. A search space corresponds to the search area and search method for PDCCH candidates. A CORESET can also be associated with one or more search spaces. The UE can also monitor the CORESET associated with a search space based on the search space settings.

[0158] A search space may also correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may also be referred to as a search space set. Furthermore, the terms "search space," "search space set," "search space configuration," "search space set configuration," "CORESET," and "CORESET configuration" in this disclosure may be used interchangeably.

[0159] Uplink control information (uplink control information (UCI)) including at least one of channel state information (CSI), delivery confirmation information (e.g., hybrid automatic repeat request acknowledgment (HARQ-ACK)), ACK / NACK, etc.), and a scheduling request (SR) may also be transmitted via the PUCCH. A random access preamble used to establish a connection with a cell may also be transmitted via the PRACH.

[0160] In this disclosure, terms such as downlink and uplink may be expressed without the word "link." Furthermore, various channels may be expressed without the word "Physical" at the beginning.

[0161] In the wireless communication system 1, a synchronization signal (Synchronization Signal (SS)), a downlink reference signal (Downlink Reference Signal (DL-RS)), etc. may also be transmitted. In the wireless communication system 1, as DL-RS, a cell-specific reference signal (Cell-specific Reference Signal (CRS)), a channel state information reference signal (Channel State Information Reference Signal (CSI-RS)), a demodulation reference signal (DeModulation Reference Signal (DMRS)), a positioning reference signal (Positioning Reference Signal (PRS)), a phase tracking reference signal (Phase Tracking Reference Signal (PTRS)), etc. may also be transmitted.

[0162] For example, a synchronization signal may be at least one of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). A signal block containing SSs (PSS, SSS) and PBCHs (and DMRS for PBCHs) may also be referred to as an SS / PBCH block or an SS block (SSB). Furthermore, SSs and SSBs may also be referred to as reference signals.

[0163] In addition, in the wireless communication system 1, as an uplink reference signal (UL-RS), a measurement reference signal (Sounding Reference Signal (SRS)), a demodulation reference signal (DMRS), etc. can also be transmitted. In addition, DMRS can also be called a user terminal specific reference signal (UE-specific Reference Signal).

[0164] (Base Station)

[0165] Figure 10 This figure shows an example of the configuration of a base station according to one embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission path interface (transmission line interface) 140. Furthermore, more than one of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140 may be provided.

[0166] In addition, in this example, the functional blocks of the characteristic parts of this embodiment are mainly shown, and it is also assumed that the base station 10 also has other functional blocks required for wireless communication. Part of the processing of each unit described below may be omitted.

[0167] The control unit 110 controls the entire base station 10. The control unit 110 can be composed of a controller, a control circuit, and the like that are described based on the common knowledge in the technical field to which this disclosure relates.

[0168] The control unit 110 may also control signal generation, scheduling (e.g., resource allocation, mapping), etc. It may also control transmission and reception, measurement, etc., using the transmission and reception unit 120, the transmission and reception antennas 130, and the transmission path interface 140. The control unit 110 may also generate data, control information, sequences, etc. to be transmitted as signals, and forward them to the transmission and reception unit 120. The control unit 110 may also perform call processing (setting up, releasing, etc.) of communication channels, manage the status of the base station 10, manage radio resources, etc.

[0169] The transceiver unit 120 may also include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may also include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may include a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter (phase shifter), a measurement circuit, a transceiver circuit, and the like, which are described based on the common knowledge in the technical field involved in this disclosure.

[0170] The transmitting and receiving unit 120 may be configured as an integrated transmitting and receiving unit, or may be configured as a transmitting unit and a receiving unit. The transmitting unit may also be configured as a transmitting processing unit 1211 and an RF unit 122. The receiving unit may also be configured as a receiving processing unit 1212, an RF unit 122, and a measuring unit 123.

[0171] The transmitting and receiving antenna 130 can be formed of an antenna described based on the common knowledge in the technical field to which this disclosure relates, such as an array antenna.

[0172] The transmitting and receiving unit 120 may also transmit the aforementioned downlink channel, synchronization signal, downlink reference signal, etc. The transmitting and receiving unit 120 may also receive the aforementioned uplink channel, uplink reference signal, etc.

[0173] The transmitting and receiving unit 120 may also use digital beamforming (eg, precoding), analog beamforming (eg, phase rotation), etc. to form at least one of a transmit beam and a receive beam.

[0174] The sending and receiving unit 120 (sending processing unit 1211) can also perform processing on the Packet Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer (for example, RLC retransmission control), the Medium Access Control (MAC) layer (for example, HARQ retransmission control), etc. on the data and control information obtained from the control unit 110 to generate a bit string to be sent.

[0175] The transmitting and receiving unit 120 (transmitting processing unit 1211) can also perform channel coding (which may also include error correction coding), modulation, mapping, filtering, discrete Fourier transform (DFT)) processing (as needed), inverse fast Fourier transform (IFFT)) processing, precoding, digital-to-analog conversion and other transmission processing on the bit string to be sent, and output a baseband signal.

[0176] The transmitting and receiving unit 120 (RF unit 122 ) may also perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the signal in the radio frequency band via the transmitting and receiving antenna 130 .

[0177] On the other hand, the transmitting and receiving unit 120 (RF unit 122 ) may also perform amplification, filtering, and demodulation into a baseband signal on the radio frequency band signal received by the transmitting and receiving antenna 130 .

[0178] The transmitting and receiving unit 120 (receiving processing unit 1212) can also apply receiving processing such as analog-to-digital conversion, fast Fourier transform (FFT) processing, inverse discrete Fourier transform (IDFT) processing (as needed), filtering processing, demapping, demodulation, decoding (which may also include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the obtained baseband signal to obtain user data, etc.

[0179] The transmitting and receiving unit 120 (measuring unit 123) may also perform measurements related to the received signal. For example, the measuring unit 123 may also perform radio resource management (RRM) measurements, channel state information (CSI) measurements, etc. based on the received signal. The measuring unit 123 may also measure received power (e.g., reference signal received power (RSRP)), received quality (e.g., reference signal received quality (RSRQ)), signal to interference plus noise ratio (SINR), signal to noise ratio (SNR)), signal strength (e.g., received signal strength indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may also be output to the control unit 110.

[0180] The transmission path interface 140 can also send and receive signals (return signaling) between the devices included in the core network 30, other base stations 10, etc., and can also obtain and transmit user data (user plane data) and control plane data for the user terminal 20.

[0181] In addition, the transmitting unit and the receiving unit of the base station 10 in the present disclosure may also be constituted by at least one of the transmitting and receiving unit 120 , the transmitting and receiving antenna 130 , and the transmission path interface 140 .

[0182] In addition, the transceiver unit 120 may also transmit control information (e.g., PDCCH indication (PDCCH-order)) for instructing the transmission of a random access preamble. In addition, the transceiver unit 120 may also transmit a response signal corresponding to the random access preamble. In addition, the transceiver unit 120 may also transmit information related to the configuration of the PTRS (e.g., higher layer signaling).

[0183] The control unit 110 may also assume that the presence or absence of the phase tracking reference signal (PTRS) during initial transmission and the presence or absence of the PTRS during retransmission are set to be common to control reception. Alternatively, the control unit 110 may also assume that the presence or absence of the phase tracking reference signal (PTRS) during initial transmission and the presence or absence of the PTRS during retransmission are set independently (for example, differently) to control reception.

[0184] Alternatively, the control unit 110 may specify using downlink control information so that the same transport block size is applied to initial transmission and retransmission of the PUSCH.

[0185] (User Terminal)

[0186] Figure 11 This figure shows an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transmitting / receiving unit 220, and a transmitting / receiving antenna 230. Furthermore, more than one of each of the control unit 210, the transmitting / receiving unit 220, and the transmitting / receiving antenna 230 may be provided.

[0187] In this example, the functional blocks of the characteristic parts of this embodiment are mainly shown, but it is also assumed that the user terminal 20 also has other functional blocks required for wireless communication. Part of the processing of each unit described below may be omitted.

[0188] The control unit 210 controls the entire user terminal 20. The control unit 210 can be composed of a controller, a control circuit, and the like that are described based on the common knowledge in the technical field to which this disclosure relates.

[0189] The control unit 210 may also control signal generation, mapping, etc. The control unit 210 may also control transmission, reception, measurement, etc. using the transmission and reception unit 220 and the transmission and reception antenna 230. The control unit 210 may also generate data, control information, sequences, etc. to be transmitted as signals and forward them to the transmission and reception unit 220.

[0190] The transceiver unit 220 may also include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may also include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may include a transmitter / receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, and the like, which are described based on the common knowledge in the technical field involved in this disclosure.

[0191] The transmitting and receiving unit 220 may be configured as an integrated transmitting and receiving unit, or may be configured as a transmitting unit and a receiving unit. The transmitting unit may also be configured as a transmitting processing unit 2211 and an RF unit 222. The receiving unit may also be configured as a receiving processing unit 2212, an RF unit 222, and a measuring unit 223.

[0192] The transmitting and receiving antenna 230 can be formed of an antenna described based on the common knowledge in the technical field to which this disclosure relates, such as an array antenna.

[0193] The transmitting and receiving unit 220 may also receive the aforementioned downlink channel, synchronization signal, downlink reference signal, etc. The transmitting and receiving unit 220 may also transmit the aforementioned uplink channel, uplink reference signal, etc.

[0194] The transmitting and receiving unit 220 may also use digital beamforming (eg, precoding), analog beamforming (eg, phase rotation), etc. to form at least one of a transmitting beam and a receiving beam.

[0195] The sending and receiving unit 220 (sending processing unit 2211) can also perform PDCP layer processing, RLC layer processing (for example, RLC retransmission control), MAC layer processing (for example, HARQ retransmission control), etc. on the data, control information, etc. obtained from the control unit 210 to generate a bit string to be sent.

[0196] The transmitting and receiving unit 220 (transmitting processing unit 2211) can also perform channel coding (which may also include error correction coding), modulation, mapping, filtering, DFT processing (as needed), IFFT processing, precoding, digital-to-analog conversion and other transmission processing on the bit string to be sent, and output a baseband signal.

[0197] In addition, whether or not to apply DFT processing may also be based on the transform precoding setting. For a certain channel (e.g., PUSCH), if transform precoding is activated (enabled), the transmitting / receiving unit 220 (transmitting processing unit 2211) may also perform DFT processing as the aforementioned transmission processing in order to transmit the channel using a DFT-s-OFDM waveform. Otherwise, the transmitting / receiving unit 220 (transmitting processing unit 2211) may also perform DFT processing as the aforementioned transmission processing without performing DFT processing.

[0198] The transmitting and receiving unit 220 (RF unit 222 ) may also perform modulation, filtering, amplification, etc. on the baseband signal into a radio frequency band, and transmit the signal in the radio frequency band via the transmitting and receiving antenna 230 .

[0199] On the other hand, the transmitting and receiving unit 220 (RF unit 222 ) may also perform amplification, filtering, and demodulation into a baseband signal on the radio frequency band signal received via the transmitting and receiving antenna 230 .

[0200] The transmitting and receiving unit 220 (receiving processing unit 2212) can also apply analog-to-digital conversion, FFT processing, IDFT processing (as needed), filtering processing, demapping, demodulation, decoding (which may also include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the obtained baseband signal to obtain user data, etc.

[0201] The transmitting and receiving unit 220 (measuring unit 223) may also perform measurements related to received signals. For example, the measuring unit 223 may also perform RRM measurements, CSI measurements, etc. based on the received signals. The measuring unit 223 may also measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may also be output to the control unit 210.

[0202] In addition, the transmitting unit and the receiving unit of the user terminal 20 in the present disclosure may also be composed of at least one of the transmitting and receiving unit 220 and the transmitting and receiving antenna 230 .

[0203] In addition, the transceiver unit 220 may also receive control information (e.g., PDCCH indication (PDCCH-order)) for instructing the transmission of a random access preamble. In addition, the transceiver unit 120 may also transmit a random access preamble. In addition, the transceiver unit 120 may also receive a response signal corresponding to the random access preamble. In addition, the transceiver unit 120 may also receive information related to the configuration of the PTRS (e.g., higher layer signaling).

[0204] The control unit 210 may also control, when transmitting an uplink shared channel based on the response signal, whether or not a phase tracking reference signal (PTRS) is transmitted in the initial transmission and whether or not the PTRS is transmitted in the retransmission are common. Furthermore, even if the control unit 210 receives information related to PTRS configuration, it may control whether or not the PTRS is transmitted in the initial transmission and the retransmission regardless of the information.

[0205] Alternatively, when transmitting an uplink shared channel based on an acknowledgement signal, the control unit 210 may separately control whether a phase tracking reference signal (PTRS) is transmitted in the initial transmission and whether the PTRS is transmitted in the retransmission. Furthermore, even when receiving information related to PTRS configuration, the control unit 210 may control the transmission of the PTRS in either the initial transmission or the retransmission independently of the information, thereby preventing the PTRS from being transmitted in the other transmission.

[0206] When the modulation and coding scheme index included in the downlink control information for scheduling retransmission of the uplink shared channel is a specific value, the control unit 210 may perform retransmission using the same transport block size as that for the initial transmission.

[0207] (Hardware Structure)

[0208] In addition, the block diagrams used in the description of the above embodiments show blocks of functional units. These functional blocks (structural units) are implemented by any combination of at least one of hardware and software. In addition, the implementation method of each functional block is not particularly limited. That is, each functional block can be implemented by a device that is physically or logically combined, or two or more physically or logically separated devices can be directly or indirectly connected (for example, by wired, wireless, etc.) and implemented by these multiple devices. The functional block can also be implemented by combining the above-mentioned one device or the above-mentioned multiple devices with software.

[0209] Here, the functions include judging, deciding, determining, calculating, calculating, processing, deriving, investigating, searching, confirming, receiving, sending, outputting, accessing, resolving, selecting, selecting, establishing, comparing, assuming, expecting, regarding, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc., but are not limited to these. For example, a functional block (structural unit) that implements a sending function may also be referred to as a transmitting unit, a transmitter, etc. Any of them are as described above, and the implementation method is not particularly limited.

[0210] For example, a base station, a user terminal, etc. in one embodiment of the present disclosure may also function as a computer that performs processing of the wireless communication method of the present disclosure. Figure 12 This figure shows an example of the hardware configuration of a base station and a user terminal according to one embodiment. The base station 10 and user terminal 20 described above can also be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

[0211] In addition, in this disclosure, the terms such as device, circuit, equipment, section, and unit are interchangeable. The hardware structure of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the figure, or may be configured to exclude some of the devices.

[0212] For example, although only one processor 1001 is shown, multiple processors may be provided. Furthermore, processing may be performed by a single processor, or by two or more processors simultaneously, sequentially, or using other methods. Furthermore, processor 1001 may be implemented using more than one chip.

[0213] Regarding the various functions in the base station 10 and the user terminal 20, for example, they are achieved by reading specific software (program) into hardware such as the processor 1001 and the memory 1002, so that the processor 1001 performs calculations and controls communication via the communication device 1004, or controls at least one of the reading and writing of data in the memory 1002 and the storage 1003.

[0214] The processor 1001 controls the entire computer by, for example, operating an operating system. The processor 1001 may also be composed of a central processing unit (CPU) including an interface with peripheral devices, a control device, a computing device, registers, etc. For example, at least a portion of the aforementioned control unit 110 (210) and the transmitting and receiving unit 120 (220) may also be implemented by the processor 1001.

[0215] In addition, the processor 1001 reads a program (program code), a software module, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002 and performs various processes based on them. As a program, a program that causes a computer to perform at least a portion of the operations described in the above embodiments can be used. For example, the control unit 110 (210) can also be implemented by a control program stored in the memory 1002 and operated by the processor 1001, and the same can be achieved for other functional blocks.

[0216] The memory 1002 may also be a computer-readable recording medium, for example, composed of at least one of a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), or other appropriate storage medium. The memory 1002 may also be referred to as a register, a cache, a main memory (main storage device), etc. The memory 1002 can store executable programs (program code), software modules, etc. for implementing the wireless communication method according to one embodiment of the present disclosure.

[0217] The storage 1003 may also be a computer-readable recording medium, such as a flexible disk, a floppy disk, an optical / magnetic disk (such as a compact disk (Compact Disc ROM (CD-ROM)), etc.), a digital versatile disk, a Blu-ray disk, a removable disk, a hard disk drive, a smart card, a flash memory device (such as a card, a stick, or a key drive), a magnetic stripe, a database, a server, or other appropriate storage media. The storage 1003 may also be referred to as an auxiliary storage device.

[0218] The communication device 1004 is hardware (a transmitting and receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, a network controller, a network card, a communication module, or the like. To implement at least one of frequency division duplex (FDD) and time division duplex (TDD), the communication device 1004 may also be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, and the like. For example, the aforementioned transmitting and receiving unit 120 (220) and the transmitting and receiving antenna 130 (230) may also be implemented by the communication device 1004. The transmitting and receiving unit 120 (220) may also be physically or logically separated from the transmitting unit 120a (220a) and the receiving unit 120b (220b).

[0219] The input device 1005 is an input device that receives input from the outside (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to the outside (e.g., a display, speaker, light emitting diode (LED) lamp, etc.). Alternatively, the input device 1005 and the output device 1006 may be integrated (e.g., a touch panel).

[0220] Furthermore, the processor 1001, memory 1002, and other devices are connected via a bus 1007 for communicating information. The bus 1007 may be configured as a single bus or may be configured as different buses between the devices.

[0221] Furthermore, the base station 10 and user terminal 20 may also be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA). Such hardware may be used to implement part or all of the functional blocks. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0222] (Variation)

[0223] In addition, the terms described in this disclosure and the terms required for understanding this disclosure may also be replaced with terms having the same or similar meanings. For example, channel, symbol, and signal (signal or signaling) may be replaced with each other. In addition, a signal may also be a message. A reference signal may also be referred to as RS, or may be referred to as a pilot, pilot signal, etc. depending on the applied standard. In addition, a component carrier (CC) may also be referred to as a cell, frequency carrier, carrier frequency, etc.

[0224] A radio frame can also be composed of one or more periods (frames) in the time domain. Each period (frame) of the one or more periods (frames) that constitute a radio frame can also be called a subframe. Furthermore, a subframe can also be composed of one or more time slots in the time domain. A subframe can also be a fixed time length (e.g., 1 ms) that is independent of the parameter set (numerology).

[0225] Here, a parameter set may also refer to communication parameters applied to at least one of the transmission and reception of a signal or channel. For example, a parameter set may also represent at least one of subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), the number of symbols per TTI, radio frame structure, specific filtering processing performed by the transmitter and receiver in the frequency domain, specific windowing processing performed by the transmitter and receiver in the time domain, and the like.

[0226] A time slot may also be composed of one or more symbols (Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.) in the time domain. In addition, a time slot may also be a time unit based on a parameter set.

[0227] A time slot may also contain multiple mini-slots. Each mini-slot may also be composed of one or more symbols in the time domain. Furthermore, a mini-slot may also be referred to as a sub-slot. A mini-slot may also be composed of fewer symbols than a time slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a mini-slot may also be referred to as PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a mini-slot may also be referred to as PDSCH (PUSCH) mapping type B.

[0228] Radio frames, subframes, time slots, mini-time slots, and symbols all represent time units used for signal transmission. Radio frames, subframes, time slots, mini-time slots, and symbols may also be referred to by their respective equivalents. Furthermore, the terms frame, subframe, time slot, mini-time slot, and symbol may be used interchangeably in this disclosure.

[0229] For example, a subframe can also be called a TTI, multiple consecutive subframes can also be called a TTI, and a time slot or a mini-time slot can also be called a TTI. In other words, at least one of the subframe and the TTI can be a subframe (1ms) in existing LTE, a period shorter than 1ms (for example, 1-13 symbols), or a period longer than 1ms. In addition, the unit representing the TTI can also be called a time slot, a mini-time slot, etc. instead of a subframe.

[0230] Here, TTI refers to, for example, the minimum time unit for scheduling in wireless communications. For example, in the LTE system, a base station schedules each user terminal by allocating radio resources (such as the frequency bandwidth and transmit power available to each user terminal) in TTI units. The definition of TTI is not limited to this.

[0231] The TTI may also be a unit of time for transmitting channel-coded data packets (transport blocks), code blocks, code words, etc., and may also be a unit of processing for scheduling, link adaptation, etc. Furthermore, when a TTI is given, the time interval (e.g., the number of symbols) to which the transport blocks, code blocks, code words, etc. are actually mapped may be shorter than the TTI.

[0232] Furthermore, when a time slot or a mini-time slot is referred to as a TTI, one or more TTIs (i.e., one or more time slots or one or more mini-time slots) may also be the minimum time unit for scheduling. Furthermore, the number of time slots (mini-time slots) constituting the minimum time unit for scheduling may also be controlled.

[0233] A TTI having a time length of 1 ms may also be referred to as a normal TTI (TTI in 3GPP Rel. 8-12), a standard TTI, a long TTI, a normal subframe, a standard subframe, a long subframe, a time slot, etc. A TTI shorter than a normal TTI may also be referred to as a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a mini-slot, a subslot, a time slot, etc.

[0234] In addition, long TTI (for example, normal TTI, subframe, etc.) can also be interpreted as TTI with a time length exceeding 1ms, and short TTI (for example, shortened TTI, etc.) can also be interpreted as TTI with a TTI length smaller than long TTI and greater than 1ms.

[0235] A resource block (RB) is a unit of resource allocation in the time and frequency domains. In the frequency domain, it may also include one or more consecutive subcarriers (subcarriers). The number of subcarriers included in an RB can also be the same regardless of the parameter set, for example, it can be 12. The number of subcarriers included in an RB can also be determined based on the parameter set.

[0236] In addition, an RB may also include one or more symbols in the time domain, and may also be the length of a slot, a mini-slot, a subframe, or a TTI. A TTI, a subframe, etc. may also be composed of one or more resource blocks.

[0237] In addition, one or more RBs may also be referred to as a physical resource block (Physical RB (PRB)), a sub-carrier group (Sub-Carrier Group (SCG)), a resource element group (Resource Element Group (REG)), a PRB pair, an RB pair, etc.

[0238] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0239] A Bandwidth Part (BWP) (also referred to as a fractional bandwidth) can also represent a subset of contiguous common resource blocks (RBs) used for a parameter set within a carrier. Common RBs can also be identified by their index relative to the common reference point of the carrier. PRBs can also be defined within a BWP and numbered within that BWP.

[0240] The BWP may include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). For a UE, one or more BWPs may be configured within one carrier.

[0241] At least one of the configured BWPs may be activated, and the UE may not assume that it will transmit or receive specific signals / channels outside of the activated BWP. Furthermore, terms such as "cell" and "carrier" in this disclosure may also be interpreted as "BWPs."

[0242] The above-mentioned structures of radio frames, subframes, slots, mini-slots, and symbols are merely examples. For example, various modifications may be made to the number of subframes in a radio frame, the number of slots per subframe or radio frame, the number of mini-slots within a slot, the number of symbols and RBs within a slot or mini-slot, the number of subcarriers within an RB, the number of symbols within a TTI, the symbol length, and the cyclic prefix (CP) length.

[0243] Furthermore, the information and parameters described in this disclosure may be expressed as absolute values, relative values ​​relative to a specific value, or other corresponding information. For example, wireless resources may be indicated by specific indexes.

[0244] In this disclosure, the names used for parameters, etc., are not intended to be limiting in any respect. Furthermore, the mathematical formulas for these parameters, etc., may differ from those explicitly disclosed in this disclosure. Various channels (PUCCH, PDCCH, etc.) and information elements can be identified by any suitable names, and therefore, the various names assigned to these various channels and information elements are not intended to be limiting in any respect.

[0245] Information, signals, and the like described in this disclosure may also be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, and the like that may be referred to throughout the foregoing description may also be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any combination thereof.

[0246] Furthermore, information, signals, etc. can be output from a higher layer (upper layer) to a lower layer (lower layer), or from a lower layer to a higher layer. Information, signals, etc. can also be input and output via multiple network nodes.

[0247] Input and output information, signals, etc. can be stored in a specific location (e.g., memory) or managed using a management table. Input and output information, signals, etc. can be overwritten, updated, or appended. Output information, signals, etc. can also be deleted. Input information, signals, etc. can also be sent to other devices.

[0248] The notification of information is not limited to the methods / implementations described in the present disclosure, and may also be performed by other methods. For example, the notification of information in the present disclosure may also be implemented through physical layer signaling (e.g., downlink control information (Downlink Control Information (DCI))), uplink control information (Uplink Control Information (UCI))), high-layer signaling (e.g., Radio Resource Control (RRC)) signaling, broadcast information (Master Information Block (MIB)), System Information Block (SIB), etc.), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

[0249] In addition, physical layer signaling may also be referred to as Layer 1 / Layer 2 (L1 / L2) control information (L1 / L2 control signal), L1 control information (L1 control signal), etc. In addition, RRC signaling may also be referred to as RRC message, for example, RRC Connection Setup message, RRC Connection Reconfiguration message, etc. In addition, MAC signaling may also be notified using MAC Control Element (CE), for example.

[0250] Furthermore, notification of specific information (eg, notification of “yes X”) is not limited to explicit notification, but may also be performed implicitly (eg, by not notifying the specific information or by notifying other information).

[0251] The determination can be made by a value represented by a bit (0 or 1), a true or false value (Boolean value) represented by true (true) or false (false), or by comparison of numerical values ​​(for example, comparison with a specific value).

[0252] Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or by other names, shall be construed broadly to mean instructions, instruction sets, codes, code segments, program code, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, or the like.

[0253] Furthermore, software, instructions, information, and the like may also be transmitted and received via a transmission medium. For example, if the software is transmitted from a website, server, or other remote source using at least one of a wired technology (coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), etc.) and a wireless technology (infrared, microwave, etc.), at least one of these wired and wireless technologies is included within the definition of a transmission medium.

[0254] The terms "system" and "network" used in this disclosure can be used interchangeably. "Network" may also refer to devices included in the network (eg, base stations).

[0255] In the present disclosure, terms such as "precoding", "precoder", "weight (precoding weight)", "Quasi-Co-Location (QCL))", "Transmission Configuration Indication state (TCI state)", "spatial relation", "spatial domain filter", "transmission power", "phase rotation", "antenna port", "antenna port group", "layer", "number of layers", "rank", "resource", "resource set", "resource group", "beam", "beam width", "beam angle", "antenna", "antenna element", and "panel" can be used interchangeably.

[0256] In this disclosure, terms such as "base station (BS)", "wireless base station", "fixed station", "NodeB", "eNB (eNodeB)", "gNB (gNodeB)", "access point", "transmission point (TP)", "reception point (RP)", "transmission / reception point (TRP)"), "panel", "cell", "sector", "cell group", "carrier", and "component carrier" are used interchangeably. In some cases, a base station may be referred to as a macro cell, small cell, femto cell, or pico cell.

[0257] A base station can accommodate one or more (for example, three) cells. When a base station accommodates multiple cells, the base station's overall coverage area can be divided into multiple smaller areas, each of which can also provide communication services through a base station subsystem (for example, a small base station (Remote Radio Head (RRH)) for indoor use). Terms such as "cell" or "sector" refer to a portion or the entire coverage area of ​​at least one of a base station and a base station subsystem providing communication services within that coverage area.

[0258] In the present disclosure, terms such as “mobile station (MS)”, “user terminal”, “user device (UE)”, and “terminal” are used interchangeably.

[0259] A mobile station is also sometimes referred to as a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other appropriate terminology.

[0260] At least one of the base station and the mobile station may also be referred to as a transmitting device, a receiving device, a wireless communication device, etc. Furthermore, at least one of the base station and the mobile station may also be a device mounted on a mobile object, a mobile object itself, etc. The mobile object may be a vehicle (e.g., a vehicle, an aircraft, etc.), a mobile object that moves unmanned (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Furthermore, at least one of the base station and the mobile station may also include a device that does not necessarily move when performing communication operations. For example, at least one of the base station and the mobile station may also be an Internet of Things (IoT) device such as a sensor.

[0261] In addition, the base station in the present disclosure can also be interpreted as a user terminal. For example, the various methods / implementations of the present disclosure can also be applied to a structure in which the communication between a base station and a user terminal is replaced by communication between multiple user terminals (for example, it can also be called device-to-device (D2D)), vehicle-to-everything (V2X), etc.). In this case, it can also be set as a structure in which the user terminal 20 has the functions of the above-mentioned base station 10. In addition, expressions such as "uplink" and "downlink" can also be interpreted as expressions corresponding to communication between terminals (for example, "side"). For example, uplink channels, downlink channels, etc. can also be interpreted as side channels.

[0262] Likewise, the user terminal in the present disclosure may also be interpreted as a base station. In this case, the base station 10 may also have the functions of the user terminal 20 described above.

[0263] In the present disclosure, actions are assumed to be performed by a base station, and sometimes, depending on the circumstances, by its upper node. Obviously, in a network including one or more network nodes including a base station, various actions performed for communication with a terminal may be performed by the base station, one or more network nodes other than the base station (for example, a Mobility Management Entity (MME)), a Serving-Gateway (S-GW), etc., but not limited to these), or a combination thereof.

[0264] The various methods / implementations described in this disclosure may be used individually or in combination, and may be switched between them during execution. Furthermore, the processing procedures, sequences, flow charts, and the like of the various methods / implementations described in this disclosure may be reversed as long as they do not conflict. For example, the elements of various steps described in this disclosure are presented in an illustrative order, but are not limited to the specific order presented.

[0265] The various modes and embodiments described in the present disclosure may also be applied to Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New Radio Access (NX), Future Generation Radio Access (FX), Global System for Mobile Communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.18 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (WiMAX (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 (WiMAX (registered trademark)), IEEE 802.30 (WiMAX (registered trademark)), IEEE 802.31 (WiMAX (registered trademark)), IEEE 802.32 (WiMAX (registered trademark)), IEEE 802.33 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), systems using other appropriate wireless communication methods, and next-generation systems based on these. In addition, multiple systems can also be combined for application (for example, LTE or LTE-A combined with 5G, etc.).

[0266] The phrase "based on" used in this disclosure does not mean "based only on" unless otherwise specified. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0267] Any reference to an element using the designations "first," "second," etc., as used in this disclosure, does not necessarily define the quantity or order of these elements. These designations may be used in this disclosure as a convenient means of distinguishing between two or more elements. Thus, reference to a first and a second element does not necessarily imply that only two elements may be used, or that the first element necessarily takes precedence over the second element in some manner.

[0268] The term "determining" as used in this disclosure may encompass a variety of actions. For example, "determining" may also include judging, calculating, computing, processing, deriving, investigating, looking up (e.g., searching in a table, database, or other data structure), and ascertaining.

[0269] In addition, "judgment (decision)" can also regard receiving (for example, receiving information), transmitting (for example, sending information), input (input), output (output), accessing (for example, accessing data in a memory), etc. as situations of making "judgment (decision)".

[0270] Furthermore, "judgment (decision)" can also include resolving, selecting, choosing, establishing, and comparing. In other words, "judgment (decision)" can also include some actions as situations in which "judgment (decision)" is performed.

[0271] In addition, "judgment (decision)" can also be interpreted as "assuming", "expecting", "considering", etc.

[0272] As used in this disclosure, the terms "connected," "coupled," and all variations thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between the two elements being "connected" or "coupled." The coupling or connection between elements can be physical, logical, or a combination of these. For example, "connected" can also be interpreted as "access."

[0273] In the present disclosure, when two elements are connected, it can be considered that they are "connected" or "combined" to each other using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy with wavelengths in the wireless frequency domain, microwave region, light (both visible and invisible) region, etc. as several non-limiting and non-inclusive examples.

[0274] In this disclosure, the term "A is different from B" can also mean "A and B are different from each other." Furthermore, the term can also mean "A and B are each different from C." Terms such as "separate" and "bound" can also be interpreted as meaning "different."

[0275] In this disclosure, when the terms "include," "including," and variations thereof are used, these terms, like the term "comprising," have an inclusive meaning. Furthermore, the term "or" used in this disclosure does not mean an exclusive OR.

[0276] In the present disclosure, when an article is added by translation, such as a, an, and the in English, the present disclosure may also include a case where the noun following the article is in a plural form.

[0277] While the inventions disclosed herein have been described in detail above, it will be apparent to those skilled in the art that the inventions disclosed herein are not limited to the embodiments described herein. The inventions disclosed herein can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the claims. Therefore, the descriptions in this disclosure are for illustrative purposes only and are not intended to limit the inventions disclosed herein in any way.< / ptrs>

Claims

1. A terminal, characterized in that: have: a receiving unit, receiving a random access response (RAR) corresponding to the random access preamble; a sending unit, configured to send an uplink shared channel based on the UL sending indication included in the random access response; as well as a control unit configured to control not to transmit a phase tracking reference signal (PTRS) in transmission of the uplink shared channel and not to transmit the PTRS in retransmission of the uplink shared channel in contention-based random access; The retransmission of the uplink shared channel is a retransmission of the message after receiving the random access response. The control unit does not transmit a phase tracking reference signal (PTRS) in transmission of an uplink shared channel scheduled by a UL grant (RARUL grant) included in a random access response in a non-contention-based random access. The control unit supports transmission of the PTRS in retransmission of the uplink shared channel scheduled using the DCI scrambled by the CRC using the C-RNTI in non-contention-based random access.

2. A wireless communication method, which is a wireless communication method of a terminal, characterized in that: have: receiving a random access response (RAR) corresponding to the random access preamble; A step of sending an uplink shared channel based on the UL sending indication included in the random access response; as well as performing control so as not to transmit a phase tracking reference signal (PTRS) in transmission of the uplink shared channel and not to transmit the PTRS in retransmission of the uplink shared channel in contention-based random access, The retransmission of the uplink shared channel is a retransmission of the message after receiving the random access response. The terminal does not transmit a phase tracking reference signal (PTRS) in transmission of an uplink shared channel scheduled by a UL grant (RAR UL grant) included in a random access response in a non-contention-based random access. The terminal supports transmission of PTRS in retransmission of the uplink shared channel scheduled using DCI scrambled by CRC using C-RNTI in non-contention-based random access.

3. A base station, characterized in that: have: A sending unit, sending a random access response (RAR) corresponding to the random access preamble; as well as a receiving unit configured to receive an uplink shared channel transmitted based on a UL transmission instruction included in the random access response, In contention-based random access, the receiving unit does not receive a phase tracking reference signal (PTRS) during transmission of the uplink shared channel and retransmission of the uplink shared channel. The retransmission of the uplink shared channel is a retransmission of a message after the terminal receives the random access response. The receiving unit does not receive a phase tracking reference signal (PTRS) in transmission of an uplink shared channel scheduled by a UL grant (RARUL grant) included in a random access response in a non-contention-based random access. The receiving unit supports reception of PTRS in retransmission of the uplink shared channel scheduled using DCI scrambled by CRC using C-RNTI in non-contention-based random access.

4. A system having a terminal and a base station, characterized in that: The terminal has: a receiving unit, receiving a random access response (RAR) corresponding to the random access preamble; a sending unit, configured to send an uplink shared channel based on the UL sending indication included in the random access response; as well as a control unit configured to control not to transmit a phase tracking reference signal (PTRS) in transmission of the uplink shared channel and not to transmit the PTRS in retransmission of the uplink shared channel in contention-based random access; The retransmission of the uplink shared channel is a retransmission of the message after receiving the random access response. The control unit does not transmit a phase tracking reference signal (PTRS) in transmission of an uplink shared channel scheduled by a UL grant (RARUL grant) included in a random access response in a non-contention-based random access. The control unit supports transmission of PTRS in retransmission of the uplink shared channel scheduled using DCI scrambled by CRC using C-RNTI in non-contention random access. The base station has: a sending unit, configured to send the random access response corresponding to the random access preamble; and The receiving unit receives an uplink shared channel transmitted based on the UL transmission instruction included in the random access response.

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