Terminal

Abstract

This terminal comprises: a transmission unit that transmits, in a time unit in which time division duplexing is applied, a preamble for starting random access; and a control unit that executes, during trying and retrying of the random access, power ramping for increasing the transmission power of the preamble. During the trying and retrying of the random access, the control unit determines, on the basis of a condition, whether or not to perform switching between a unit time of a first type and a unit time of a second type, where a duplexing scheme which allows simultaneously use of a plurality of sub-bands in the time unit in which the time division duplexing is applied is not applied to the unit time of the first type, and the duplexing scheme is applied to the unit time of the second type.

Description

Terminal

[0001] The present disclosure relates to a terminal that supports subband non-overlapping full duplex (SBFD).

[0002] The 3rd Generation Partnership Project (3GPP (registered trademark)) has specified the 5th generation mobile communication system (5G, also known as New Radio (NR) or Next Generation (NG)), and is also working on specifications for next-generation mobile communication systems called Beyond 5G, 5G Evolution, or 6G.

[0003] Release 18 discusses a duplexing scheme that enables simultaneous use of downlink (DL) and uplink (UL) by utilizing multiple subbands that make up a time division duplexing (TDD) band. This duplexing scheme is called subband non-overlapping full duplex (SBFD). Symbols to which SBFD is applied may also be called SBFD symbols. In addition, in SBFD symbols, subbands used for DL ​​may also be called DL subbands, and subbands used for UL may also be called UL subbands.

[0004] Furthermore, support for random access (RA) in SBFD is being considered for Release 19 (Non-Patent Document 1). Specifically, it is being considered to extend the configuration related to the random access channel (RACH) (RACH configuration) to the SBFD symbol.

[0005] A terminal (hereinafter also referred to as a user equipment (UE)) determines a random access opportunity (RO) for transmitting a preamble to start a random access (RA) based on a RACH configuration from a base station (hereinafter also referred to as a gNodeB (gNB)), and further determines a valid RO (and an invalid RO) from the determined ROs. Furthermore, the valid RO is mapped to an index of a synchronization signal block (SSB index) based on SSB-to-RO mapping.

[0006] “New WID: Evolution of NR duplex operation: Sub-band full duplex (SBFD)”, RP-234035, 3GPP TSG RAN Meeting #102, 3GPP, December 11-15, 2023

[0007] However, if an RA attempt fails (i.e., if a Physical Random Access Channel (PRACH) transmission fails), the UE may consider power ramping to increase the transmit power for the PRACH transmission in the next RA attempt (RA retry), which is achieved by incrementing the value of a Power Ramping Counter (PRC).

[0008] Here, if an RA attempt in an SBFD symbol fails, an RA retry may be performed in an SBFD symbol or in a non-SBFD symbol. Similarly, if an RA attempt in a non-SBFD symbol fails, an RA retry may be performed in an SBFD symbol or in a non-SBFD symbol. In any of these four patterns, the above-mentioned power ramping may be applied.

[0009] However, since SBFD symbols perform UL transmission within a DL symbol, for example, DL reception within the same symbol may interfere with UL transmission. Thus, SBFD symbols have different characteristics from non-SBFD symbols in terms of interference. In light of these characteristics of SBFD symbols, simply applying power ramping without considering the difference in symbols between an RA attempt and the next RA attempt is not necessarily appropriate, and may even cause new interference with other UEs due to unnecessary power ramping.

[0010] Therefore, an object of the present disclosure is to provide a terminal that can perform power ramping in an RA retry, taking into consideration the difference between the symbol type in an RA attempt and the symbol type in an RA retry.

[0011] An aspect of the disclosure is a terminal comprising: a transmitting unit that transmits a preamble that initiates random access in a time unit in which time division duplexing is applied; and a control unit that executes power ramping that increases the transmission power of the preamble in an attempt and a retry of the random access, wherein the control unit determines, based on a condition, whether to switch between a first type of unit time in which a duplexing method that allows simultaneous use of multiple subbands is not applied and a second type of unit time in which the duplexing method is applied in the attempt and the retry of the random access.

[0012] FIG. 1 is a diagram showing an overall schematic configuration of a wireless communication system. FIG. 2 is a diagram showing frequency ranges used in the wireless communication system. FIG. 3 is a diagram showing example configurations of radio frames, subframes, slots, and symbols used in the wireless communication system. FIG. 4 is a functional block diagram of a terminal. FIG. 5 is a functional block diagram of a base station. FIG. 6 is a diagram showing example SBFD slots / symbols. FIG. 7 is a diagram showing an example in which symbol switching is not performed between a RACH attempt and a RACH retry. FIG. 8 is a diagram showing an example in which symbol switching is performed between a RACH attempt and a RACH retry. FIG. 9 is a diagram showing an example in which power ramping is applicable when switching between SBFD / non-SBFD symbols. FIG. 10 is a diagram showing an example in which power ramping is applicable when switching between SBFD / non-SBFD symbols. FIG. 11 is an example in which different power ramping counters are used for SBFD symbols and non-SBFD symbols. FIG. 12 is an example in which different power ramping counters are used for SBFD symbols and non-SBFD symbols. FIG. 13 is a diagram for explaining Operation Example 4. FIG. 14 is a diagram for explaining Operation Example 4. Fig. 15 is a diagram for explaining operation example 4. Fig. 16 is a diagram for explaining operation example 5. Fig. 17 is a diagram for explaining operation example 5. Fig. 18 is a diagram showing an example of the hardware configuration of a base station and a terminal. Fig. 19 is a diagram showing an example of the configuration of a vehicle.

[0013] Hereinafter, embodiments will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and descriptions thereof will be omitted as appropriate.

[0014] (1) Configuration of Wireless Communication System The wireless communication system 10 shown in Fig. 1 is a wireless communication system conforming to a method called 5G. Alternatively, the wireless communication system 10 may be a wireless communication system conforming to a method called Beyond 5G, 5G Evolution, or 6G.

[0015] The wireless communication system 10 can support Massive Multiple-Input Multiple-Output (Massive MIMO), which generates more directional beams by controlling wireless signals transmitted from multiple antenna elements, Carrier Aggregation (CA), which uses multiple component carriers (CCs) as a bundle, and Dual Connectivity (DC), which enables simultaneous communication with two base stations.

[0016] As shown in FIG. 1 , the wireless communication system 10 includes a base station 100 (hereinafter also referred to as a gNodeB (gNB) 100) constituting a Next Generation-Radio Access Network (NG-RAN) 20, and a terminal 200 (hereinafter also referred to as a user equipment (UE) 200) that performs wireless communication with the gNB 100. The NG-RAN 20 is connected to a core network (CN) (not shown). The CN is composed of multiple network functions (NFs). The NFs are, for example, an access and mobility management function (AMF) and a network data analytics function (NWDAF). The AMF performs, for example, registration of the UE 200. The NWDAF performs, for example, optimization of the CN. Note that the specific configuration of the wireless communication system 10, for example, the number of gNBs 100 and UEs 200, is not limited to the example shown in FIG. 1 . The NG-RAN 20 and the CN may be simply referred to as a "network."

[0017] The gNB100 may be a base station in a Centralized-Radio Access Network (C-RAN) configuration having a distributed unit (DU) having a function for connecting to the UE200 and a central unit (CU) having a function for connecting to the network. In this case, the gNB100 may be read as a DU, a CU, or a DU and a CU. When the gNB100 is read as a DU, it may be called a gNB-DU. When the gNB100 is read as a CU, it may be called a gNB-CU. When the gNB100 is read as a DU and a CU, the DU portion may be called a gNB-DU and the CU portion may be called a gNB-CU.

[0018] The wireless communication system 10 may also support multiple frequency ranges (FR), i.e., the following FRs as shown in FIG.

[0019] FR1: 410 MHz to 7.125 GHz FR2-1: 24.25 GHz to 52.6 GHz FR2-2: Over 52.6 GHz to 71 GHz In FR1, a subcarrier spacing (SCS) of 15, 30, or 60 kHz and a bandwidth (BW) of 5 to 100 MHz may be used. In FR2-1, an SCS of 60 or 120 kHz (or 240 kHz) and a BW of 50 to 400 MHz may be used.

[0020] In FR2-2, to avoid an increase in phase noise, Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) or Discrete Fourier Transform-Spread-Orthogonal Frequency Division Multiplexing (DFT-S-OFDM) with a larger SCS may be applied.

[0021] 3, one slot in the wireless communication system 10 is composed of 14 symbols. If this configuration is maintained, the larger (wider) the SCS, the shorter the symbol period (and slot period). Note that the SCS is not limited to the frequencies shown in FIG. 3 and may be, for example, 480 kHz, 960 kHz, or other frequencies.

[0022] Furthermore, the number of symbols constituting one slot does not necessarily have to be 14, but may be, for example, 28 or 56. Furthermore, the number of slots per subframe may differ depending on the SCS.

[0023] (2) Functional Block Configuration of Wireless Communication System (2.1) Functional Block Configuration of Terminal As shown in FIG. 4, the UE 200 includes a wireless signal transmitting / receiving unit 210, an amplifier unit 220, a modulation / demodulation unit 230, a control signal / reference signal processing unit 240, an encoding / decoding unit 250, a data transmitting / receiving unit 260, and a control unit 270.

[0024] The radio signal transceiver 210 transmits and receives radio signals to and from the gNB 100. The radio signal transceiver 210 may be configured with a transmitter that transmits radio signals to the gNB 100 and a receiver that receives radio signals from the gNB 100. The radio signals may include data or may be interpreted as data. Transmission may be interpreted as report, notification, etc. Reception may be interpreted as (configured), (instructed), (notified), etc. Note that configuration may be realized by configuration information (information element (IE)) of the radio resource control (RRC) layer, and instruction may be realized by a control element (CE) or downlink control information (DCI) of the medium access control (MAC) layer.

[0025] The radio signal transceiver 210 of the embodiment can attempt random access (RA) to the gNB 100. Specifically, the radio signal transceiver 210 can transmit a preamble (Msg1) to the gNB 100. The RA may be a four-step random access using Msg1 to Msg4 (and a HARQ-ACK PUCCH for Msg4), or a two-step random access using MsgA and MsgB. Note that in this specification, the term "preamble" may be replaced with "PRACH."

[0026] The radio signal transceiver 210 of the embodiment can transmit a preamble at a valid random access opportunity. The random access opportunity may be interpreted as a timing for transmitting a preamble to start an RA. The random access opportunity may also be referred to as a RACH Occasion (RO). The RO is set based on the RACH setting from the gNB 100. For details about a valid RO, see the description of the control unit 270.

[0027] In the embodiment, the radio signal transceiver 210 can transmit a preamble again when a random access attempt fails. In other words, the radio signal transceiver 210 can transmit a first preamble for attempting random access and a second preamble for retrying random access. Note that "attempting random access" may be interpreted as a concept that includes "retrying random access." In other words, "attempting random access" is not limited to the first random access, but may also refer to the second or subsequent random access. In this case, "retrying random access" may also refer to the third or subsequent random access. Furthermore, a random access attempt / retry may be interpreted as a temporally earlier / later random access among two or more random access attempts.

[0028] The time unit in which the radio signal transceiver 210 transmits the preamble may be a first type of time unit (i.e., non-SBFD slot / symbol) that applies time division duplexing (TDD), or a second type of time unit (i.e., SBFD slot / symbol) that can utilize multiple subbands that make up the TDD band. That is, the radio signal transceiver 210 can transmit the first and second preambles described above in the first type of time unit or the second type of time unit. Note that the radio signal transceiver 210 can transmit the first and second preambles in the same type of time unit, or in different types of time units.

[0029] The second type of time unit (i.e., SBFD slot / symbol) may be interpreted as being based on the first type of time unit (i.e., non-SBFD slot / symbol). In other words, the SBFD slot / symbol is based on the TDD slot / symbol and may be interpreted as a TDD slot / symbol that can (simultaneously) use multiple subbands that make up the TDD band.

[0030] The amplifier unit 220 is configured by a power amplifier (PA) / low noise amplifier (LNA), etc. The amplifier unit 220 amplifies the radio signal output from the radio signal transmitting / receiving unit 210. The amplifier unit 220 also amplifies the radio signal output from the modulation / demodulation unit 230.

[0031] The modem unit 230 performs data modulation / demodulation, transmission power setting, resource block allocation, etc. for each predetermined communication destination (gNB100 or another gNB100). CP-OFDM / DFT-S-OFDM may be applied to the modem unit 230. Furthermore, DFT-S-OFDM may be used not only for the uplink (UL) but also for the downlink (DL).

[0032] The control signal / reference signal processing unit 240 performs processing related to control signals transmitted and received between the gNB 100, such as radio resource control (RRC) signaling.

[0033] The control signal / reference signal processing unit 240 performs processing related to reference signals transmitted and received between the gNB 100, such as Demodulation Reference Signal (DMRS), Phase Tracking Reference Signal (PTRS), Channel State Information-Reference Signal (CSI-RS), Sounding Reference Signal (SRS), and Positioning Reference Signal (PRS).

[0034] The channels include control channels and data channels. The control channels include a physical uplink control channel (PUCCH), a physical downlink control channel (PDCCH), a physical random access channel (PRACH), a physical broadcast channel (PBCH), etc. The data channels include a physical uplink shared channel (PUSCH), a physical downlink shared channel (PDSCH), etc.

[0035] The encoding / decoding unit 250 performs division / concatenation and coding / decoding of data contained in the radio signal for each predetermined communication destination (gNB100 or another gNB100).

[0036] Specifically, the encoding / decoding unit 250 decodes the data output from the modem unit 230 and concatenates the decoded data. In addition, the encoding / decoding unit 250 divides the data output from the data transmitter / receiver 260 into pieces of a predetermined size and performs coding on the divided data.

[0037] The data transmitter / receiver 260 assembles and disassembles data units (Protocol Data Units (PDUs) / Service Data Units (SDUs)) that make up data between each layer. The multiple layers include a Medium Access Control (MAC) layer, a Radio Link Control (RLC) layer, and a Packet Data Convergence Protocol (PDCP) layer. The data transmitter / receiver 260 also performs data error correction and retransmission control based on Hybrid Automatic Repeat Request (HARQ).

[0038] The control unit 270 controls the UE 200. The control unit 270 controls, for example, transmission and reception of radio signals by the radio signal transmission and reception unit 210, amplification by the amplifier unit 220, data modulation / demodulation by the modem unit 230, signal processing by the control signal and reference signal processing unit 240, coding / decoding by the encoding / decoding unit 250, and assembly / disassembly of data units by the data transmission and reception unit 260.

[0039] The control unit 270 of the embodiment can determine the above-mentioned valid RO and an invalid RO, which is an invalid RO, based on the RACH configuration from the gNB100. Specifically, the control unit 270 determines an RO that transmits a preamble from among the ROs configured based on the RACH configuration from the gNB100, and further determines, from among the determined ROs, a valid RO that actually transmits a preamble (can transmit) and an invalid RO that does not transmit a preamble (cannot transmit). For rules for determining a valid RO, please refer to the description of the operation example.

[0040] The control unit 270 of the embodiment can determine the application of power ramping to the transmission of the second preamble described above. That is, the control unit 270 can apply power ramping to the preamble to be transmitted in a retry of random access when random access fails. Similarly, the control unit 270 can also not apply power ramping to the preamble to be transmitted in a retry of random access even when random access fails.

[0041] In the embodiment, the control unit 270 can apply power ramping to the transmission of the second preamble based on whether the type of time unit for transmitting the first preamble in the random access attempt is the same as the type of time unit for transmitting the second preamble in the random access retry (i.e., based on whether the type of time unit for transmitting the first preamble and the type of time unit for transmitting the second preamble are different types or the same type).

[0042] Specifically, when the type of time unit for transmitting the first preamble is the same as the type of time unit for transmitting the second preamble, the control unit 270 can apply power ramping to the transmission of the second preamble. For example, as shown in the upper part of FIG. 7 , when both the first preamble and the second preamble are transmitted in SBFD symbols, the control unit 270 can apply power ramping to the transmission of the second preamble. Also, as shown in the lower part of FIG. 7 , when both the first preamble and the second preamble are transmitted in non-SBFD symbols, the control unit 270 can apply power ramping to the transmission of the second preamble. Note that the symbol type for transmitting the first preamble and the second preamble is the same regardless of whether symbol switching, which will be described in the operational example, is possible. In other words, the fact that symbol switching is possible does not contradict the fact that the symbol type for transmitting the first preamble and the second preamble is the same.

[0043] On the other hand, when the type of time unit for transmitting the first preamble is different from the type of time unit for transmitting the second preamble, the control unit 270 can not apply power ramping to the transmission of the second preamble. For example, as shown in the upper part of FIG. 8 , when the first preamble is transmitted in an SBFD symbol while the second preamble is transmitted in a non-SBFD symbol, the control unit 270 can not apply power ramping to the transmission of the second preamble. Also, as shown in the lower part of FIG. 8 , when the first preamble is transmitted in a non-SBFD symbol while the second preamble is transmitted in an SBFD symbol, the control unit 270 can not apply power ramping to the transmission of the second preamble. Note that "not applying power ramping" may be interpreted as "cancelling the application of power ramping" or "stopping the application of power ramping," etc.

[0044] Furthermore, the control unit 270 can apply no power ramping to the transmission of the second preamble when the first preamble is transmitted in a second type of time unit (i.e., SBFD slot / symbol).On the other hand, the control unit 270 can also apply no power ramping to the transmission of the second preamble when the second preamble is transmitted in a second type of time unit (i.e., SBFD slot / symbol).

[0045] The control unit 270 of the embodiment may apply power ramping to the second preamble by controlling a power ramping counter (PRC). Details will be described in an operation example, but as shown in Figures 11 and 12, the control unit 270 can separately control the ramping counter for the preamble transmitted in the first type of time unit (i.e., non-SBFD slots / symbols) and the ramping counter for the preamble transmitted in the second type of time unit (i.e., SBFD slots / symbols).

[0046] (2.2) Functional block configuration of base station As shown in Figure 5, the gNB100 includes a radio signal transceiver unit 110 and a control unit 120.

[0047] The radio signal transmitting / receiving unit 110 transmits and receives radio signals to and from the UE 200. The radio signal transmitting / receiving unit 110 may be configured with a transmitting unit that transmits radio signals to the UE 200 and a receiving unit that receives radio signals from the UE 200. The radio signals may include data or may be interpreted as data. Transmission may be interpreted as configuration, instruction, notification, etc. Reception may be interpreted as (reported), notification, etc. Note that configuration may be realized by configuration information (information element (IE)) of a radio resource control (RRC) layer, and instruction may be realized by a control element (CE) or downlink control information (DCI) of a medium access control (MAC) layer.

[0048] The radio signal transmitting and receiving unit 110 according to the embodiment can transmit (set) a RACH configuration to the UE 200 .

[0049] The control unit 120 controls the gNB 100. The control unit 120 controls, for example, the transmission and reception of radio signals by the radio signal transmission and reception unit 110. The control unit 120 also performs scheduling for the UE 200.

[0050] The control unit 120 can control handover (HO) of the UE 200. HO may be understood as, for example, transition of the UE 200 from the gNB 100 to which it is connected to another gNB 100. Note that the gNB 100 to which the UE 200 is connected in HO may be interpreted as a cell or beam formed by the gNB 100. HO may also be interpreted as a term such as cell transition, cell change, or beam change.

[0051] (3) SBFD As shown in Fig. 6, SBFD may be applied to each slot / symbol. Note that, in addition to DL and UL, each slot / symbol may be set to Flexible (FL) that can be used as DL or UL, and then SBFD may be applied.

[0052] SBFD is a type of (full-duplex) duplexing scheme based on time division duplexing (TDD), enabling simultaneous use of multiple sub-bands that make up the TDD band. SBFD can be described as a duplexing scheme in which multiple sub-bands are specified within the TDD band, a duplexing scheme in which UL and DL are allocated non-overlapping in the frequency direction within the TDD time unit, or full-duplex duplexing of sub-bands.

[0053] A slot / symbol to which SBFD is applied is also referred to as an SBFD slot / symbol. "SBFD is applied" may be interpreted as SBFD being applied to at least a part of scheduling. In other words, "slot / symbol to which SBFD is applied" may be interpreted as a slot / symbol to which SBFD is applied in scheduling to which SBFD is applied (SBFD slot / symbol). Also, "time unit to which non-SBFD is applied" may be interpreted as a slot / symbol to which SBFD is not applied in scheduling to which SBFD is applied (non-SBFD slot / symbol).

[0054] As shown in Figure 6, each subband (SBFD subband) constituting an SBFD slot / symbol is assigned DL or UL. Hereinafter, a subband assigned DL is also referred to as a DL subband, and a subband assigned UL is also referred to as a UL subband. In Figure 6, slots / symbols or subbands marked with "D" are DL slots / symbols or DL ​​subbands, and slots / symbols or subbands marked with "U" are UL slots / symbols or UL subbands. Note that slots / symbols marked with "F" in other figures are FL slots / symbols.

[0055] Below, we will briefly explain the terms related to SBFD.

[0056] SBFD DL symbol: A symbol specified for DL ​​by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated, and a symbol for which the SBFD subband is set. SBFD FL symbol: A symbol specified for FL by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated, and a symbol for which the SBFD subband is set. SBFD SSB symbol: A symbol specified for SSB reception, and a symbol for which the SBFD subband is set. non-SBFD symbol: A symbol for which the SBFD subband is not set.

[0057] (4) Operation of the Wireless Communication System (4.1) Issues If an RA attempt in an SBFD symbol fails, the RA retry may be performed in an SBFD symbol or in a non-SBFD symbol. Similarly, if an RA attempt in a non-SBFD symbol fails, the RA retry may be performed in an SBFD symbol or in a non-SBFD symbol. In any of these four patterns, the power ramping described above may be applied.

[0058] However, since SBFD symbols perform UL transmission within a DL symbol, for example, DL reception within the same symbol may interfere with UL transmission. Thus, SBFD symbols have different characteristics from non-SBFD symbols in terms of interference. In light of these characteristics of SBFD symbols, simply applying power ramping without considering the difference in symbols between an RA attempt and the next RA attempt is not necessarily appropriate, and may even cause new interference with other UEs due to unnecessary power ramping.

[0059] (4.2) Separate Transmission Power Control for SBFD Symbols and Non-SBFD Symbols (4.2.1) Transmission Power Control for PRACH As a first aspect, separate PRACH power parameters may be set or indicated for PRACH transmissions in SBFD symbols and for PRACH transmissions in non-SBFD symbols. For example, a separate preamble target power parameter may be set to calculate PREAMBLE_RECEIVED_TARGET_POWER.

[0060] Example 1: preambleReceivedTargetPower (or msgA-PreambleReceivedTargetPower for two-step random access) is used for PRACH transmission in non-SBFD symbols, and a new parameter preambleReceivedTargetPower-sbfd-r19 (or msgA-PreambleReceivedTargetPower-sbfd-r19 for two-step random access) may be configured and used for PRACH transmission in SBFD symbols. Note that the content of Example 1 may be applied to Options 1, 2, and 3 of Example 1 described below, and may be applied to Options 1 and 2 of Example 2 described below.

[0061] Example 2: preambleReceivedTargetPower in the RACH configuration for non-SBFD may be used for PRACH transmission in non-SBFD symbols, and preambleReceivedTargetPower (or preambleReceivedTargetPower-sbfd-r19, or msgA-PreambleReceivedTargetPower or msgA-PreambleReceivedTargetPower-sbfd-r19 in the case of two-step random access) in the RACH configuration for SBFD may be used for PRACH transmission in SBFD symbols. Note that the content of Example 2 may be applied to Option 4 of Example 1 described below, or may be applied to Option 3 of Example 2 described below.

[0062] <Example 1> Example 1 determines a valid RO for random access (RA) in RRC_IDLE mode or IN_ACTIVE mode, or for RA based on cell-common RACH configuration (or RACH configuration indicated in SIB1), and includes the following options 1 to 4.

[0063] <Option 1> Option 1 is a combination of a legacy RACH configuration and a legacy rule for determining a valid RO. Note that the legacy RACH configuration may be understood as a RACH configuration for non-SBFD symbols, and a configuration for determining an RO for non-SBFD symbols in particular. On the other hand, a RACH configuration for SBFD symbols may be performed, and an RO for SBFD symbols in particular may be determined, based on the legacy RACH configuration.

[0064] In option 1, the UE 200 may operate as follows.

[0065] Step 1: Determine the RO based on the legacy RACH configuration.

[0066] ・Step 2: From the determined ROs, determine the valid ROs using legacy rules.

[0067] Step 3: The determined valid RO is mapped to an SSB index according to the legacy SSB-RO mapping rules.

[0068] Step 4: Transmit the selected preamble at the selected RO.

[0069] <Option 2> Option 2 is a combination of the legacy RACH configuration and the extended rules for determining a valid RO. For details of the "extended rules for determining a valid RO," see the "(4.2.3.3) Terminology" section below.

[0070] In option 2, UE 200 may operate as follows.

[0071] Step 1: Determine the RO based on the legacy RACH configuration.

[0072] Step 2: From the determined RO, determine the valid RO using the extended rules.

[0073] Step 3: The determined valid RO is mapped to an SSB index according to the legacy SSB-RO mapping rules.

[0074] Step 4: Transmit the selected preamble at the selected RO.

[0075] Option 3 Option 3 combines legacy RACH configuration with legacy and extended rules for determining valid ROs.

[0076] In option 3, the UE 200 may operate as follows.

[0077] Step 1: Determine the RO based on the legacy RACH configuration.

[0078] Step 2A-1: From the determined ROs, a valid RO is determined according to the legacy rule. This valid RO may be called a legacy-valid RO.

[0079] Step 2A-2: The determined valid RO is mapped to an SSB index according to the legacy SSB-RO mapping rules.

[0080] Step 2B-1: From the determined ROs (within the SBFD DL symbol (and / or SBFD SSB symbol) or overlapping with the SBFD DL symbol (and / or SBFD SSB symbol)), determine additional valid ROs according to the extension rule.

[0081] Step 2B-2: The determined additional valid ROs are mapped to SSB indices.

[0082] Step 3: Transmit the selected preamble at the selected RO.

[0083] <Option 4> Option 4 combines an additional / separate RACH configuration (relative to the legacy RACH configuration) (also referred to in this specification as a RACH configuration for SBFD or an additional RACH configuration for SBFD) with an extended rule for determining a valid RO. The RACH configuration for SBFD may be interpreted as a RACH configuration for SBFD symbols, and as a configuration that specifically determines an RO for the SBFD symbols. On the other hand, a RACH configuration for non-SBFD symbols may be configured, or an RO for non-SBFD symbols may be specifically determined, based on the RACH configuration for SBFD.

[0084] In option 4, the UE 200 may operate as follows.

[0085] Step 1A: Determine the RO based on the legacy RACH configuration.

[0086] Step 2A: From the determined ROs, determine the valid ROs using legacy rules.

[0087] Step 3A: The determined valid RO is mapped to an SSB index according to the legacy SSB-RO mapping rules.

[0088] Step 1B: Determine the RO based on the RACH configuration for SBFD.

[0089] Step 2B: Determine a valid RO according to the legacy rule from the RO determined based on the RACH configuration for SBFD.

[0090] Step 3B: The determined valid RO is mapped to an SSB index according to the legacy SSB-RO mapping rules.

[0091] Step 4: Transmit the selected preamble at the selected RO.

[0092] Note that since SBFD-aware UE only uses the RACH configuration for SBFD, Steps 1A to 3A may be omitted.

[0093] <Example 2> Example 2 determines a valid RO for random access (RA) in RRC_IDLE mode or IN_ACTIVE mode, or for RA based on dedicated configuration (e.g., RA for BFR based on BeamFailureRecoveryConfig and / or contention-free random access (CFRA) based on RACH-ConfigDedicated and / or RA for SI-RequestConfig), and includes the following options 1 to 3.

[0094] Note that an RA based on a common configuration (cell-common RACH configuration) and an RA based on a dedicated configuration differ in the following respects: That is, an RA based on a common configuration needs to take into consideration how a Legacy UE understands or interprets the configuration, whereas an RA based on a dedicated configuration does not need to take into consideration how a Legacy UE understands or interprets the configuration.

[0095] <Option 1> Based on the rach-ConfigBFR configured as usual in BeamFailureRecoveryConfig and / or the cfra configured as usual in RACH-ConfigDedicated and / or the rach-ConfigSI configured as usual in SI-RequestConfig, an SBFD-aware UE always uses the "extended rules for determining valid RO" described in "(4.2.3.3) Terminology" below.

[0096] <Option 2> Whether to always use the "extended rules for determining valid RO" in "(4.2.3.3) Terminology" below is configured by the gNB based on rach-ConfigBFR, which is configured as usual in BeamFailureRecoveryConfig, and / or cfra, which is configured as usual in RACH-ConfigDedicated, and / or rach-ConfigSI, which is configured as usual in SI-RequestConfig.

[0097] <Option 3> Additional / separate configuration for RACH resource configuration for SBFD is performed, and to determine a valid RO for the RACH resource configuration for SBFD, the UE uses the "extended rules for determining valid RO" in "(4.2.3.3) Terminology" described later.

[0098] - Example: BeamFailureRecoveryConfig-sbfd-r19 is set. Or, rach-ConfigBFR-sbfd-r19 is set in BeamFailureRecoveryConfig. - Example: RACH-ConfigDedicated-sbfd-r19 is set. Or, cfra-sbfd-r19 is set in RACH-ConfigDedicated. Or, occasions-sbfd-r19 is set in CFRA. Or, ConfigGeneric-sbfd-r19 is set in occasions of CFRA. And / or - CFRA-TwoStep-sbfd-r19 is set in RACH-ConfigDedicated. Or, occasionsTwoStepRA-sbfd-r19 is set in CFRA-TwoStep. Alternatively, ConfigGenericTwoStepRA-sbfd-r19 is set in occasionsTwoStepRA-sbfd-r19 of CFRA-TwoStep. Note that as a variation, two mask index values ​​are set for SBFD and non-SBFD in CFRA or CFRA-TwoStep.

[0099] Example: SI-RequestConfig-sbfd-r19 is set. Alternatively, rach-OccasionsSI-sbfd-r19 is set in SI-RequestConfig. Alternatively, rach-ConfigSI-sbfd-r19 is set in rach-OccasionsSI of SI-RequestConfig. As a variation, two mask index values ​​are set in SI-RequestResources, one for SBFD and one for non-SBFD.

[0100] Next, as a second aspect, a (target) power offset may be configured or indicated for PRACH transmission in SBFD symbols. For example, for PRACH transmission in non-SBFD symbols, the conventional power calculation rule may be applied, and for PRACH transmission in SBFD symbols, the above-mentioned (target) power offset may be added (reduced) based on the conventional power calculation rule.

[0101] For example, for PRACH transmission in an SBFD symbol, the following formula may be applied: Note that SBFD_offset in the formula may be set or indicated by the gNB 100, and the value of SBFD_offset (dB) may be positive (e.g., +1 / 2 / 3 dB) or negative (e.g., −1 / 2 / 3 dB).

[0102] P PRACH,b,f,c (i) = min {P CMAX,f,c (i), P PRACH,target,f,c + PL b,f,c + SBFD_offset} [dBm]

[0103] (4.2.2) Transmission Power Control of MsgA PUSCH First, as a first aspect, a delta preamble power parameter for the MsgA PUSCH in an SBFD symbol and a delta preamble power parameter for the MsgA PUSCH in a non-SBFD symbol may be set / indicated separately. For example, separate delta preamble power parameters may be set to calculate PREAMBLE_RECEIVED_TARGET_POWER.

[0104] Example 1: msgA-DeltaPreamble or deltaPreamble may be used for MsgA PUSCH transmission in non-SBFD symbols, and new parameters msgA-DeltaPreamble-sbfd-r19 or deltaPreamble-sbfd-r19 may be configured and used for MsgA PUSCH transmission in SBFD symbols. Note that the content of Example 1 may be applied when individual MsgA configuration is not performed between SBFD and non-SBFD.

[0105] Example 2: A msgA-DeltaPreamble or deltaPreamble in the MsgA configuration for non-SBFD may be used for MsgA PUSCH transmission in a non-SBFD symbol, and a msgA-DeltaPreamble or deltaPreamble (or msgA-DeltaPreamble-sbfd-r19 or DeltaPreamble-sbfd-r19) in the MsgA configuration for SBFD may be used for MsgA PUSCH transmission in an SBFD symbol. Note that the contents of Example 2 may be applied when individual MsgA configurations are performed between SBFD and non-SBFD.

[0106] Next, as a second aspect, a (target) power offset may be set or indicated for MsgA PUSCH transmission in SBFD symbols. For example, for MsgA PUSCH transmission in non-SBFD symbols, the conventional power calculation rule may be applied, and for MsgA PUSCH transmission in SBFD symbols, the above-mentioned (target) power offset may be added (reduced) based on the conventional power calculation rule.

[0107] For example, for MsgA PUSCH transmission in an SBFD symbol, the following formula may be applied: Note that SBFD_offset in the formula may be set or indicated by the gNB 100, and the value of SBFD_offset (dB) may be positive (e.g., +1 / 2 / 3 dB) or negative (e.g., −1 / 2 / 3 dB).

[0108] P O_NOMINAL_PUSCH,f,c (0) = P O_PRE + Δ MsgAPUSCH + SBFD_offset

[0109] (4.2.3) Symbol Switching Between RACH Attempts / Retrials Symbol switching between RACH attempts / retries will be described with reference to Figures 7 and 8. Specifically, this section will describe whether switching between PRACH transmission in SBFD symbols and PRACH transmission in non-SBFD symbols is supported between a RACH attempt and a RACH retrial.

[0110] A RACH retry may be interpreted as a RACH attempt (second or later) other than the first RACH attempt. In other words, a RACH retry may be interpreted as a RACH attempt when the PREAMBLE_TRANSMISSION_COUNTER for the RACH attempt is greater than 1. A RACH retry may be triggered, for example, by failure to receive an RAR (Msg2) or a contention resolution (Msg4). A RACH retry may be interpreted as a RACH attempt following a previous RACH attempt. That is, the previous RACH attempt may be a RACH retry. On the other hand, a RACH attempt may also mean a RACH retry. That is, a RACH attempt may mean not only the first RACH attempt but also the second or later RACH attempt. Note that a RACH attempt may be interpreted as a RACH transmission, and a RACH retry may be interpreted as a RACH retransmission, respectively.

[0111] (4.2.3.1) Option 1 Option 1 is a description of a case where switching between PRACH transmission in SBFD symbols and PRACH transmission in non-SBFD symbols is not supported between a RACH attempt and a RACH retry, as shown in Fig. 7. A specific example is shown below.

[0112] Example 1-1: If a PRACH is transmitted in a valid RO within an SBFD symbol as the first RACH attempt, then PRACH transmission in a RACH retry attempt is only possible in a valid RO within an SBFD symbol.

[0113] Example 1-2: If a PRACH is transmitted in a valid RO in a non-SBFD symbol as the first RACH attempt, PRACH transmission in a RACH retry attempt is only possible in a valid RO in a non-SBFD symbol.

[0114] Example 1-3: If a PRACH is transmitted in a valid RO based on an additional RACH configuration for SBFD as the first RACH attempt, PRACH transmission in a RACH retry is only possible in a valid RO based on an additional RACH configuration for SBFD.

[0115] Example 1-4: If a PRACH is transmitted in a valid RO based on the legacy RACH configuration as the first RACH attempt, a PRACH transmission in a RACH retry is only possible in a valid RO based on the legacy RACH configuration.

[0116] (4.2.3.2) Option 2 Option 2 is a description of a case where switching between PRACH transmission in SBFD symbols and PRACH transmission in non-SBFD symbols is supported between a RACH attempt and a RACH retry, as shown in Fig. 8. Note that Option 2 may also be considered applicable to Fig. 7. In other words, Option 2 is also applicable to cases where symbol switching is not performed. A specific example is shown below.

[0117] Example 2-1: When a PRACH is transmitted in a valid RO in an SBFD symbol as the first RACH attempt, PRACH transmission in a RACH retry is possible in a valid RO in an SBFD symbol and also in a valid RO in a non-SBFD symbol.

[0118] Example 2-2: If a PRACH is transmitted in a valid RO in a non-SBFD symbol as the first RACH attempt, PRACH transmission in a RACH retry is possible in a valid RO in an SBFD symbol and also in a valid RO in a non-SBFD symbol.

[0119] Example 2-3: When a PRACH is transmitted in a valid RO based on an additional RACH configuration for SBFD as the first RACH attempt, a PRACH transmission in a RACH retry is possible in a valid RO based on an additional RACH configuration for SBFD, and also possible in a valid RO based on a legacy RACH configuration.

[0120] Example 2-4: When a PRACH is transmitted in a valid RO based on a legacy RACH configuration as the first RACH attempt, a PRACH transmission in a RACH retry is possible in a valid RO based on an additional RACH configuration for SBFD, and also in a valid RO based on a legacy RACH configuration.

[0121] (4.2.3.3) The term "additional RACH configuration for SBFD" may be interpreted as a RACH configuration additional to the "legacy RACH configuration," a RACH configuration for SBFD symbols, and a configuration that particularly determines an RO for the SBFD symbols. Note that the legacy RACH configuration may be interpreted as a RACH configuration for non-SBFD symbols and a configuration that particularly determines an RO for the non-SBFD symbols. On the other hand, the RACH configuration for SBFD symbols may be performed and the RO for the SBFD symbols may be particularly determined based on the legacy RACH configuration. Conversely, the RACH configuration for non-SBFD symbols may be performed and the RO for the non-SBFD symbols may be particularly determined based on the "additional RACH configuration for SBFD."

[0122] The "valid RO based on the additional RACH configuration for SBFD" may be interpreted as an RO that is determined to be invalid based on the "legacy rule for determining a valid RO" and is determined to be valid based on the "extended rule for determining a valid RO" from among the ROs that are further determined to be invalid. The "valid RO based on the legacy RACH configuration" may be interpreted as an RO that is determined to be valid based on the "legacy rule for determining a valid RO".

[0123] The "legacy rule for determining valid RO" is that an RO in an UL symbol (UL sub-band) or an FL symbol (not configured for SSB) as seen from the UE is considered a valid RO, and an RO in a DL symbol (DL sub-band) or an FL symbol (configured for SSB) as seen from the UE is considered an invalid RO.

[0124] The "extended rule for determining a valid RO" may be configured by the conditions for determining a valid RO shown below. Note that the extended rule for determining a valid RO is a rule for a cell in which SBFD operation is configured on the gNB side. Note that Cond-X in the figure corresponds to condition X.

[0125] Condition 1: Each symbol is a UL symbol. Condition 2: Each symbol is an FL symbol not configured for SSB. Condition 3: Each symbol is a UL symbol or an FL symbol not configured for SSB (non-SBFD). Condition 4: Each symbol is an SBFD symbol (e.g., SBFD DL symbol, and / or SBFD FL symbol, and / or SBFD SSB symbol). Condition 5: Each symbol is an SBFD symbol (e.g., SBFD DL symbol, and / or SBFD FL symbol, and / or SBFD SSB symbol) or a UL symbol (or an FL symbol not configured for SSB, or an FL symbol not configured for SSB (non-SBFD)). Condition 6: At least N_gap symbols are spaced after the last (non-SBFD) DL symbol, and / or at least N_gap symbols are spaced after the last (non-SBFD) SSB symbol, and / or the symbol does not precede an SSB symbol (in a non-SBFD symbol) in the same PRACH slot. Condition 7: A non-SBFD symbol (e.g., UL symbol or non-SBFD Condition 8: Does not overlap with both non-SBFD DL symbols or (non-SBFD) SSB symbols and SBFD symbols (e.g., SBFD DL symbols, and / or SBFD FL symbols, and / or SBFD SSB symbols). Condition 9: Does not overlap with RBs outside the UL subband in SBFD symbols (e.g., SBFD DL symbols, and / or SBFD FL symbols, and / or SBFD SSB symbols). That is, a valid RO in the extended rule for determining a valid RO may include an RO that satisfies one or more combinations of these conditions. One or more combinations of the above conditions may be predefined in the standard or may be set by the gNB. For example, a valid RO may include the following ROs:

[0126] ・Example 1: An RO that satisfies condition 1 (determined as a valid RO even under the legacy rules) ・Example 2: An RO that satisfies conditions 2 / 3 and 6 ・Example 2-1: If the parenthesized statement regarding non-SBFD in condition 6 does not apply, it will be determined as a valid RO even under the legacy rules ・Example 2-2: If the parenthesized statement regarding non-SBFD in condition 6 applies, it may be determined as an invalid RO under the legacy rules. This is because the conditions for determining a valid RO in this case are more relaxed.

[0127] ・Example 3: RO that satisfies conditions 2 / 3 and condition 9 (and condition 6) ・Example 4: RO that satisfies condition 4 (and condition 6) ・Example 5: RO that satisfies conditions 4 and condition 9 (and condition 6) ・Example 6: RO that satisfies condition 5 (and condition 6) ・Example 7: RO that satisfies conditions 5 and condition 9 (and condition 6) ・Example 8: RO that satisfies condition 7 (and at least one of conditions 6 / 8) ・Example 9: RO that satisfies condition 7 and condition 9 (and at least one of conditions 6 / 8)

[0128] (4.3) Example of Operation Based on the above-described transmit power control and symbol switch between RACH attempts / retries, an example of operation will be described.

[0129] (4.3.1) Operation Example 1 Operation example 1 will be described with reference to Fig. 7. Operation example 1 is based on option 1 in (4.2.3). That is, operation example 1 is based on the assumption that switching between PRACH transmission in SBFD symbols and PRACH transmission in non-SBFD symbols is not supported between a RACH attempt and a RACH retry, as shown in Fig. 7.

[0130] In this case, one power ramping loop is sufficient.

[0131] For the transmit power control of RACH retries, the power ramping step size for RACH attempts in SBFD symbols may be set separately from the power ramping step size for RACH attempts in non-SBFD symbols.

[0132] Example: Applied when powerRampingStep-sbfd-r19 and / or msgA-PreamblePowerRampingStep-sbfd-r19 are configured and the PRACH in the first RACH attempt / RACH retry is transmitted within the SBFD symbol.

[0133] Example: If the PRACH in the first RACH attempt / RACH retry is transmitted in a non-SBFD symbol, the legacy power ramping configuration parameters (e.g., powerRampingStep and / or msgA-PreamblePowerRampingStep) are applied.

[0134] Additionally, the maximum number of RACH attempts within an SBFD symbol may be set separately from the maximum number of RACH attempts within a non-SBFD symbol.

[0135] Example: Applied when preambleTransMax-sbfd-r19 and / or msgA-TransMax-sbfd-r19 are set and the PRACH in the first RACH attempt / RACH retry is transmitted within the SBFD symbol.

[0136] Example: If the PRACH in the first RACH attempt / RACH retry is transmitted in a non-SBFD symbol, the legacy maximum transmission setting parameters (e.g., preambleTransMax-sbfd and / or msgA-TransMax) are applied.

[0137] (4.3.2) Operation Example 2 With reference to Figures 8 to 12, Operation Example 2 is based on option 2 of (4.2.3). That is, Operation Example 2 is based on the premise that switching between PRACH transmission in SBFD symbols and PRACH transmission in non-SBFD symbols is supported between RACH attempt and RACH retry, as shown in Figure 8.

[0138] In this case, it is necessary to consider the difference in interference between SBFD symbols and non-SBFD symbols. Specifically, even if a RACH attempt in an SBFD (non-SBFD) symbol fails, the assumption of the current power ramping level for PRACH transmission in a non-SBFD (SBFD) symbol is not necessarily insufficient. Also, when a RACH attempt in an SBFD (non-SBFD) symbol fails and a RACH retry in a non-SBFD (SBFD) symbol is performed, using a fixed ramping step size may not be appropriate.

[0139] (4.3.2.1) Option 1 One common power ramping loop (Power Ramping Counter (PRC)) is maintained for PRACH transmission of SBFD symbols and non-SBFD symbols.

[0140] (4.3.2.1.1) Option 1-1 The PRC is incremented or maintained based on the legacy rule. That is, if the selected SSB is not changed, the PRC is incremented. Note that increment may be interpreted as increment.

[0141] (4.3.2.1.2) Option 1-2 The condition for increasing or maintaining the PRC may take into account whether the RO in a RACH attempt or the RO in a subsequent RACH retry occurs within an SBFD symbol or a non-SBFD symbol, as shown in Figures 9 and 10.

[0142] Example 1: As shown in the upper part of Figures 9 and 10, power ramping may be applied only when the RO in a RACH attempt and the RO in a subsequent RACH retry are within the same type of symbol. This is because a failure in an SBFD (non-SBFD) symbol does not necessarily imply power ramping of the non-SBFD (SBFD) symbol due to different interference levels between SBFD and non-SBFD symbols. A more specific example is shown below.

[0143] Example: If the RO in the previous / immediately preceding RACH attempt and the RO in the following RACH retry attempt are both contained in the SBFD symbol (and the selected SSB is not changed), the PRC is incremented.

[0144] Example: If the RO in the previous / immediately preceding RACH attempt and the RO in the following RACH retry attempt are both contained in non-SBFD symbols (and the selected SSB is not changed), the PRC is increased.

[0145] Example: If the RO in the previous RACH attempt is within an SBFD symbol and the RO selected for PRACH transmission in the following RACH retry attempt is within a non-SBFD symbol, the PRC is maintained.

[0146] Example: If the RO in the previous RACH attempt is within a non-SBFD symbol and the RO selected for PRACH transmission in the following RACH retry attempt is within a SBFD symbol, the PRC is maintained.

[0147] Example 2: As shown in the middle of Figures 9 and 10, if the RO in the previous RACH attempt is within the SBFD symbol, power ramping is not performed. This is because the failure of the PRACH transmission in the SBFD symbol may not be due to low transmit power, but may be due to, for example, UL subband interference in the SBFD symbol. In this case, power ramping is not necessarily required, as power ramping may result in the PRACH transmit power being so high that it may cause interference to other UEs. A more specific example is shown below.

[0148] Example: If the RO in the previous RACH attempt is within the SBFD symbol, the PRC is maintained.

[0149] Example: If the RO in the previous RACH attempt is within a non-SBFD symbol and the selected SSB or CSI-RS does not change, the PRC is increased.

[0150] Example 3: As shown in the lower part of Figures 9 and 10, if the RO in the subsequent RACH retry is within the SBFD symbol, power ramping is not performed. Power ramping of PRACH transmission in the SBFD symbol may cause serious UE-to-UE CLI. To avoid / suppress UE-to-UE CLI, power ramping of PRACH transmission in the SBFD symbol is not performed.

[0151] Example: If the RO in the following RACH retry is within the SBFD symbol, the PRC is maintained.

[0152] Example: If the RO in the following RACH retry is within a non-SBFD symbol and the selected SSB or CSI-RS does not change, the PRC is incremented.

[0153] (4.3.2.2) Option 2 Separate power ramping loops (power ramping counters (PRC)) are maintained for PRACH transmission of SBFD and non-SBFD symbols, as shown in Figures 11 and 12. For example, PREAMBLE_POWER_RAMPING_COUNTER_SBFD and PREAMBLE_POWER_RAMPING_COUNTER are maintained.

[0154] First, PREAMBLE_POWER_RAMPING_COUNTER_SBFD is (may be) incremented by 1 when one or more of the following conditions are met: Condition X may be interpreted as corresponding to Cond-X in the figure.

[0155] Condition 1: The PRACH transmission in the previous / immediately preceding RACH attempt is within the SBFD symbol.

[0156] Condition 2: The RO selected for PRACH transmission in the following / next / current / ongoing RACH retry is within the SBFD symbol.

[0157] Condition 3: The SSB selected from the previous / immediately preceding RACH attempt is not changed.

[0158] Condition 4: The SSB selected from the previous / immediately preceding RACH attempt in the SBFD symbol is not changed.

[0159] Conditions 1, 2, 3, and 4 may be combined in any way. For example, only condition 1, condition 1 + condition 3, condition 1 + condition 4, only condition 2, condition 2 + condition 3, condition 2 + condition 4, condition 1 + condition 2, condition 1 + condition 2 + condition 3, or condition 1 + condition 2 + condition 4 are possible. The upper parts of Figures 11 and 12 show the case where only condition 1 is satisfied.

[0160] If the required conditions are not met, PREAMBLE_POWER_RAMPING_COUNTER_SBFD is maintained.

[0161] PREAMBLE_POWER_RAMPING_COUNTER_SBFD is used for PRACH transmit power calculation in RACH retry when the selected RO in RACH retry is within the SBFD symbol. Note that separate power ramping step sizes may be configured for SBFD symbols and non-SBFD symbols. For example, powerRampingStep-sbfd-r19 and msgA-PreamblePowerRampingStep-sbfd-r19 may be configured for SBFD and applied to PREAMBLE_POWER_RAMPING_COUNTER_SBFD.

[0162] Next, the PREAMBLE_POWER_RAMPING_COUNTER is (may be) incremented by 1 if one or more of the following conditions are met: Note that condition X may be interpreted as corresponding to Cond-X in the figure.

[0163] Condition 5: The PRACH transmission in the previous / immediately preceding RACH attempt is within a non-SBFD symbol.

[0164] Condition 6: The RO selected for PRACH transmission in the following RACH retry is within a non-SBFD symbol.

[0165] Condition 7: The SSB selected from the previous / immediately preceding RACH attempt is not changed.

[0166] Condition 8: The SSB selected from the previous / immediately preceding RACH attempt in a non-SBFD symbol is not changed.

[0167] Conditions 5, 6, 7, and 8 may be combined in any way. For example, only condition 5, condition 5 + condition 7, condition 5 + condition 8, condition 6 only, condition 6 + condition 7, condition 6 + condition 8, condition 5 + condition 6, condition 5 + condition 6 + condition 7, or condition 5 + condition 6 + condition 8. The lower parts of Figures 11 and 12 show the case where only condition 5 is satisfied.

[0168] If the required conditions are not met, the PREAMBLE_POWER_RAMPING_COUNTER is maintained.

[0169] PREAMBLE_POWER_RAMPING_COUNTER is used for PRACH transmit power calculation in RACH retry if the selected RO in RACH retry is within a non-SBFD symbol.

[0170] (4.3.3) Operation Example 3 In Operation Example 3, the UE 200 in Operation Example 1 or Operation Example 2 described above stops the PRC.

[0171] (4.3.3.1) Option 1 When a PRACH in an SBFD symbol is not transmitted due to overlapping with an RB outside the UL subband, Layer 1 of UE 200 notifies the upper layer of UE 200 that the corresponding PRC is stopped. This is because if the RO of an SBFD symbol overlapping with an RB outside the UL subband is determined to be a valid RO, but UE 200 cannot actually transmit a PRACH in that RO, power ramping should not be applied. Note that in existing standards, the same consideration may be given to the case where UE 200 does not transmit a PRACH for some reason.

[0172] Example: In the case of option 1 of operation example 1 and operation example 2, if a PRACH in an SBFD symbol is not transmitted because a valid RO overlaps with an RB outside the UL subband, layer 1 of UE200 notifies the upper layer of UE200 to stop the corresponding PRC.

[0173] Example: In the case of option 2 of operation example 2, if a PRACH in an SBFD symbol is not transmitted because a valid RO overlaps with an RB outside the UL subband, layer 1 of UE200 notifies the upper layer of UE200 to stop the PRC for SBFD (e.g., PREAMBLE_POWER_RAMPING_COUNTER_SBFD).

[0174] (4.3.3.2) Option 2 When a PRACH in an SBFD symbol is transmitted, Layer 1 of UE 200 may notify upper layers of UE 200 to stop the corresponding PRC. This is because the failure of PRACH transmission in the SBFD symbol may not be due to low transmission power, but may be due to, for example, UL subband interference in the SBFD symbol. In this case, power ramping is not necessarily required. Note that, in existing standards, the same consideration may be given when UE 200 does not transmit a PRACH for some reason.

[0175] Example: In the case of option 1 of operation example 1 and operation example 2, when a PRACH is transmitted in a transmission opportunity (RO) within an SBFD symbol, layer 1 of UE200 may notify the upper layer of UE200 to stop the corresponding PRC.

[0176] Example: In the case of option 2 of operation example 2, when a PRACH is transmitted at a transmission opportunity (RO) within an SBFD symbol, layer 1 of UE200 may notify the upper layer of UE200 to stop the PRC for SBFD (e.g., PREAMBLE_POWER_RAMPING_COUNTER_SBFD).

[0177] (4.3.4) Operation example 4 (4.3.4.1) Issues As described above, in a random access attempt or retry (RACH attempt or RACH retry), there may be cases where a preamble is transmitted (PRACH transmission) in a first type unit period (non-SBFD symbols) to which SBFD is not applied, and cases where a preamble is transmitted (PRACH transmission) in a second type unit period (SBFD symbols) to which SBFD is applied.

[0178] Considering these cases, the inventors, after careful consideration, have found that, as a control parameter for the preamble, it is necessary to consider introducing a second control parameter that assumes SBFD, in addition to a first control parameter that does not assume SBFD.

[0179] Furthermore, the second control parameter is applicable to cases where switching between SBFD symbols and non-SBFD symbols is supported (see, for example, Figure 8) in addition to cases where switching between SBFD symbols and non-SBFD symbols is not supported in RACH attempts and RACH retries (see, for example, Figure 7).

[0180] Under these conditions, it has been found necessary to clarify what the second control parameter is, how the second control parameter is to be applied, and so on.

[0181] In Operation Example 4, UE 200 controls the transmission power of a preamble to be transmitted in a first type of unit time (non-SBFD symbol) to which SBFD is not applied, based on a first control parameter that does not assume a duplexing method (SBFD) that allows simultaneous use of multiple subbands in a time unit to which TDD is applied. UE 200 controls the transmission power of a preamble to be transmitted in a second type of unit time (SBFD symbol) to which SBFD is applied, based on a second control parameter that assumes SBFD. Operation Example 4 may be based on any one of Operation Examples 1 to 3 described above. The following operation examples are possible as Operation Example 4.

[0182] (4.3.4.2) Operational Example 4-1 In operational example 4-1, the second control parameters assuming SBFD are set separately from the first control parameters not assuming SBFD. The following options are possible for operational example 4-1.

[0183] In option 4-1-1, the second control parameter assuming SBFD is a parameter related to the target power of the preamble of the PRACH in the SBFD symbol. In other words, the target power of the preamble of the PRACH in the SBFD symbol is set by the second control parameter assuming SBFD.

[0184] For example, the parameter may be preambleReceivedTargetPower included in an additional / separate RACH configuration (RACH configuration for SBFD).

[0185] For example, the parameter may be a new parameter (e.g., sbfd-preambleReceivedTargetPower) included in the legacy RACH configuration or the RACH configuration for SBFD.

[0186] The UE 200 may assume that the target power of the PRACH preamble in the SBFD symbol is greater than, not greater than, less than, or not less than the target power of the PRACH preamble in the non-SBFD symbol (legacy target power).

[0187] Note that the parameter related to legacy target power is an example of a first control parameter that does not assume SBFD.

[0188] In option 4-1-2, the second control parameter assuming SBFD is a parameter related to a step size for increasing the transmission power of the PRACH preamble in the SBFD symbol. In other words, the step size for increasing the transmission power of the PRACH preamble in the SBFD symbol is set by the second control parameter assuming SBFD.

[0189] For example, the parameter may be powerRampingStep included in an additional / separate RACH configuration (RACH configuration for SBFD).

[0190] For example, the parameter may be a new parameter (e.g., sbfd-powerRampingStep) included in the legacy RACH configuration or the RACH configuration for SBFD.

[0191] UE 200 may assume that the step size for increasing the transmission power of the PRACH preamble in an SBFD symbol is greater than, not greater than, smaller than, or not smaller than the step size for increasing the transmission power of the PRACH preamble in a non-SBFD symbol (legacy step size).

[0192] Note that the parameter related to the legacy step size is an example of a first control parameter that does not assume SBFD.

[0193] In option 4-1-3, the second control parameter assuming SBFD is a parameter related to the maximum number of transmissions of the PRACH preamble in the SBFD symbol. In other words, the maximum number of transmissions of the PRACH preamble in the SBFD symbol is set by the second control parameter assuming SBFD.

[0194] For example, the parameter may be preambleTransMax included in an additional / separate RACH configuration (RACH configuration for SBFD).

[0195] For example, the parameter may be a new parameter (e.g., sbfd-preambleTransMax) included in the legacy RACH configuration or the RACH configuration for SBFD.

[0196] The UE 200 may assume that the maximum number of transmissions of the PRACH preamble in SBFD symbols is greater than, not greater than, less than, or not less than the maximum number of transmissions of the PRACH preamble in non-SBFD symbols (legacy maximum transmissions).

[0197] Note that the parameter related to the legacy step size is an example of a first control parameter that does not assume SBFD.

[0198] (4.3.4.3) Operational Example 4-2 In Operational Example 4-2, a case will be described in which switching between the first type of unit time (non-SBFD symbols) and the second type of unit time (SBFD symbols) is not supported in random access attempts and retries (RACH attempt / RACH retry) (see, for example, FIG. 13). As Operational Example 4-2, the following options are considered:

[0199] In option 4-2-1, the PRACH power of the PRACH in the SBFD symbol is determined as follows: The PRACH in the SBFD symbol may be a PRACH in a valid RO in the SBFD symbol, or may be a PRACH in a valid RO set by the RACH setting for SBFD.

[0200] Specifically, the PRACH power (PREAMBLE_RECEIVED_TARGET_POWER) of the PRACH in the SBFD symbol may be represented by preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA.

[0201] For the PRACH in the SBFD symbol, as described in operation example 4-1, a second control parameter different from the first control parameter for the case where SBFD is not assumed may be used.

[0202] For example, for preambleReceivedTargetPower, if preambleReceivedTargetPower included in the RACH configuration for SBFD or sbfd-preambleReceivedTargetPower included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-1). Otherwise, the legacy target power is applied.

[0203] For example, for PREAMBLE_POWER_RAMPING_STEP, if the powerRampingStep included in the RACH configuration for SBFD or the sbfd-powerRampingStep included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-2). Otherwise, the legacy step size is applied.

[0204] In option 4-2-2, the UE 200 determines that the random access procedure has ended in failure when the power ramping counter (REAMBLE_POWER_RAMPING_COUNTER) that counts the number of times the preamble is transmitted reaches preambleTransMax+1.

[0205] For the PRACH in the SBFD symbol, preambleTransMax is set by a second control parameter different from the first control parameter for the case where SBFD is not assumed. The PRACH in the SBFD symbol may be a PRACH in a valid RO in the SBFD symbol, or may be a PRACH in a valid RO set by the RACH configuration for SBFD.

[0206] For example, for preambleTransMax, if preambleTransMax included in the RACH configuration for SBFD or sbfd-preambleTransMax included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-3). Otherwise, the legacy maximum transmission count is applied.

[0207] For a PRACH in a non-SBFD symbol, preambleTransMax is set by the first control parameter for the case where SBFD is not assumed. The PRACH in a non-SBFD symbol may be a PRACH in a valid RO in a non-SBFD symbol, or may be a PRACH in a valid RO set by the legacy RACH configuration.

[0208] For example, for preambleTransMax, the preambleTransMax included in the legacy RACH setting is applied.

[0209] (4.3.4.4) Operation Example 4-3 In Operation Example 4-3, a case will be described in which switching between the first type of unit time (non-SBFD symbols) and the second type of unit time (SBFD symbols) is supported in random access attempts and retries (RACH attempt / RACH retry). The following options are considered for Operation Example 4-3.

[0210] In option 4-3-1, one common power ramping loop (power ramping counter (PRC)) may be maintained for PRACH transmission of SBFD symbols and non-SBFD symbols (see FIG. 14).

[0211] The PRACH power of the PRACH is determined as follows: Specifically, the PRACH power of the PRACH (PREAMBLE_RECEIVED_TARGET_POWER) may be expressed as preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA.

[0212] Regarding the maintenance or increase of the counter value, option 1 in operation example 2 may be applied.

[0213] For the PRACH in the SBFD symbol, preambleReceivedTargetPower and PREAMBLE_POWER_RAMPING_STEP are set as shown below. The PRACH in the SBFD symbol may be a PRACH in a valid RO in the SBFD symbol, or may be a PRACH in a valid RO set by the RACH configuration for SBFD.

[0214] For example, for preambleReceivedTargetPower, if preambleReceivedTargetPower included in the RACH configuration for SBFD or sbfd-preambleReceivedTargetPower included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-1). Otherwise, the legacy target power is applied.

[0215] For example, for PREAMBLE_POWER_RAMPING_STEP, if the powerRampingStep included in the RACH configuration for SBFD or the sbfd-powerRampingStep included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-2). Otherwise, the legacy step size is applied.

[0216] For a PRACH in a non-SBFD symbol, preambleReceivedTargetPower and PREAMBLE_POWER_RAMPING_STEP are set as shown below. A PRACH in a non-SBFD symbol may be a PRACH in a valid RO in a non-SBFD symbol, or may be a PRACH in a valid RO set by the legacy RACH configuration.

[0217] For example, the preambleReceivedTargetPower included in the legacy RACH configuration is applied as the preambleReceivedTargetPower.

[0218] For example, the powerRampingStep included in the legacy RACH setting is applied as the powerRampingStep.

[0219] In option 4-3-2, separate power ramping loops (power ramping counters (PRC)) may be maintained for PRACH transmissions of SBFD and non-SBFD symbols (see FIG. 15).

[0220] For a PRACH in an SBFD symbol, the PRACH power of the PRACH is determined as shown below. Specifically, the PRACH power of the PRACH (PREAMBLE_RECEIVED_TARGET_POWER) may be represented by preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER_SBFD - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA.

[0221] Here, PREAMBLE_POWER_RAMPING_COUNTER_SBFD is a counter that counts the number of PRACH transmissions in the SBFD symbol. Regarding the maintenance or increase of the counter value, Option 2 in Operation Example 2 may be applied.

[0222] For example, for preambleReceivedTargetPower, if preambleReceivedTargetPower included in the RACH configuration for SBFD or sbfd-preambleReceivedTargetPower included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-1). Otherwise, the legacy target power is applied.

[0223] For example, for PREAMBLE_POWER_RAMPING_STEP, if the powerRampingStep included in the RACH configuration for SBFD or the sbfd-powerRampingStep included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-2). Otherwise, the legacy step size is applied.

[0224] For a PRACH in a non-SBFD symbol, the PRACH power of the PRACH is determined as follows: Specifically, the PRACH power of the PRACH (PREAMBLE_RECEIVED_TARGET_POWER) may be represented by preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA.

[0225] Here, PREAMBLE_POWER_RAMPING_COUNTER is a counter that counts the number of PRACH transmissions in non-SBFD symbols. Regarding the maintenance or increase of the counter value, Option 2 in Operation Example 2 may be applied.

[0226] For example, the preambleReceivedTargetPower included in the legacy RACH configuration is applied as the preambleReceivedTargetPower.

[0227] For example, the powerRampingStep included in the legacy RACH setting is applied as the powerRampingStep.

[0228] In option 4-3-3, separate power ramping loops (power ramping counters (PRC)) may be maintained for PRACH transmissions of SBFD and non-SBFD symbols (see FIG. 15).

[0229] For a PRACH in an SBFD symbol or a non-SBFD symbol, the PRACH power of the PRACH is determined as shown below. Specifically, the PRACH power of the PRACH (PREAMBLE_RECEIVED_TARGET_POWER) is calculated as follows: preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER_SBFD - 1) × PREAMBLE_POWER_RAMPING_STEP_SBFD + (PREAMBLE_POWER_RAMPING_COUNTER - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA where PREAMBLE_POWER_RAMPING_COUNTER_SBFD is a counter that counts the number of PRACH transmissions in an SBFD symbol. Option 2 in Operation Example 2 may be applied to maintaining or increasing the counter value.

[0230] PREAMBLE_POWER_RAMPING_COUNTER is a counter that counts the number of PRACH transmissions in non-SBFD symbols. Option 2 in Operation Example 2 may be applied to maintaining or increasing the counter value.

[0231] If the powerRampingStep included in the RACH configuration for SBFD or the sbfd-powerRampingStep included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied to PREAMBLE_POWER_RAMPING_STEP_SBFD (option 4-1-2). Otherwise, the legacy step size is applied.

[0232] For PREAMBLE_POWER_RAMPING_STEP, the powerRampingStep included in the legacy RACH setting is applied.

[0233] For the preambleReceivedTargetPower for the PRACH in the SBFD symbol, if the preambleReceivedTargetPower included in the RACH configuration for SBFD or the sbfd-preambleReceivedTargetPower included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-1). Otherwise, the legacy target power is applied.

[0234] For the preambleReceivedTargetPower for the PRACH in non-SBFD symbols, the powerRampingStep included in the legacy RACH configuration is applied.

[0235] Here, the above-mentioned options 4-3-2 and 4-3-3 will be explained using the case shown in Fig. 15 as an example. The fourth RACH attempt and the fifth RACH attempt will be taken as examples.

[0236] First, the fourth RACH attempt will be described. In the fourth RACH attempt, the value of PREAMBLE_POWER_RAMPING_COUNTER_SBFD is 2, and the value of PREAMBLE_POWER_RAMPING_COUNTER is 1.

[0237] In option 4-3-2, power ramping is 1 * PREAMBLE_POWER_RAMPING_STEP, while in option 4-3-3, power ramping is 1 * PREAMBLE_POWER_RAMPING_STEP + 1 * PREAMBLE_POWER_RAMPING_STEP_SBFD.

[0238] Second, the fifth RACH attempt will be described. In the fourth RACH attempt, the value of PREAMBLE_POWER_RAMPING_COUNTER_SBFD is 2, and the value of PREAMBLE_POWER_RAMPING_COUNTER is also 2.

[0239] In option 4-3-2, power ramping is 2 * PREAMBLE_POWER_RAMPING_STEP_SBFD, while in option 4-3-3, power ramping is 2 * PREAMBLE_POWER_RAMPING_STEP_SBFD + 2 * PREAMBLE_POWER_RAMPING_STEP.

[0240] (4.3.5) Operation Example 5 (4.3.5.1) Issues As described above, in a random access attempt or retry (RACH attempt or RACH retry), a case is assumed in which a preamble is transmitted (PRACH transmission) in a first type unit period (non-SBFD symbols) to which SBFD is not applied, a case is assumed in which a preamble is transmitted (PRACH transmission) in a second type unit period (SBFD symbols) to which SBFD is applied, etc. Furthermore, a case is assumed in which switching between SBFD symbols and non-SBFD symbols is supported (see FIG. 8, etc.).

[0241] Assuming these cases, the inventors have conducted extensive research and found that it is necessary to introduce and clarify conditions in order to determine whether or not to switch between SBFD symbols and non-SBFD symbols.

[0242] In Operation Example 5, the UE 200 determines, based on a condition, whether to switch between a first type of unit time (non-SBFD symbols) to which SBFD is not applied and a second type of unit time (SBFD symbols) to which SBFD is applied in a random access attempt and retry (RACH attempt or RACH retry). Operation Example 5 may be based on any one of Operation Examples 1 to 4 described above. The following operation examples are possible as Operation Example 5.

[0243] (4.3.5.2) Operation Example 5-1 In Operation Example 5-1, switching from the second type unit time (SBFD symbols) to the first type unit time (non-SBFD symbols) is determined based on a first condition. Switching may be interpreted as fallback. The first condition is that the number of RACH attempts in SBFD symbols and / or non-SBFD symbols reaches a certain number. The certain number may be interpreted as a threshold. The following options are possible for Operation Example 5-1.

[0244] In operation example 5-1, the first condition may be that the number of RACH attempts in the SBFD symbol reaches a certain number. As operation example 5-1, the following options are considered.

[0245] Option 5-1-1 sets the threshold for switching from SBFD symbols to non-SBFD symbols.

[0246] For example, the threshold may be preambleTransMax included in an additional / separate RACH configuration (RACH configuration for SBFD), and may be used to determine whether to switch from SBFD symbols to non-SBFD symbols.

[0247] For example, the threshold may be a new parameter (e.g., sbfd-TransMax) included in the legacy RACH configuration or the RACH configuration for SBFD, and may be used to determine whether to switch from SBFD symbols to non-SBFD symbols.

[0248] The UE 200 may assume that the threshold is less than or not greater than the preambleTransMax included in the legacy RACH configuration.

[0249] In option 5-1-2, the UE 200 may perform the following operations for switching from an SBFD symbol to a non-SBFD symbol: Specifically, the case where the first RACH attempt is a PRACH transmission in an SBFD symbol will be described.

[0250] 16 , UE 200 determines to transmit a PRACH in an SBFD symbol when PREAMBLE_TRANSMISSION_COUNTER is smaller than or not larger than a threshold (preambleTransMax or sbfd-TransMax). The PRACH in an SBFD symbol may be a PRACH in a valid RO in the SBFD symbol, or may be a PRACH in a valid RO configured by the RACH configuration for SBFD.

[0251] On the other hand, as shown in Fig. 16, when PREAMBLE_TRANSMISSION_COUNTER is not greater than or less than the threshold (preambleTransMax or sbfd-TransMax), UE 200 determines to transmit a PRACH in a non-SBFD symbol. The PRACH in a non-SBFD symbol may be a PRACH in a valid RO in a non-SBFD symbol, or may be a PRACH in a valid RO set by a legacy RACH setting.

[0252] Option 5-1-3 describes the power ramping counter (PRC). When switching from an SBFD symbol to a non-SBFD symbol, the value of the power ramping counter may be as follows:

[0253] In Alt. 1, the value of the power ramping counter may be reset to zero.

[0254] In Alt. 2, the value of the power ramping counter may be carried over without incrementing.

[0255] In Alt. 3, the value of the power ramping counter may be incremented by one and then carried over.

[0256] Option 5-1-4 describes the determination of transmission power, specifically, the case where the first RACH attempt is a PRACH transmission in the SBFD symbol.

[0257] For a RACH attempt (PRACH transmission) in an SBFD symbol, the PRACH power of the PRACH is determined as follows: Specifically, the PRACH power of the PRACH (PREAMBLE_RECEIVED_TARGET_POWER) may be represented by preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA.

[0258] For example, for preambleReceivedTargetPower, if preambleReceivedTargetPower included in the RACH configuration for SBFD or sbfd-preambleReceivedTargetPower included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-1). Otherwise, the legacy target power is applied.

[0259] For example, for PREAMBLE_POWER_RAMPING_STEP, if the powerRampingStep included in the RACH configuration for SBFD or the sbfd-powerRampingStep included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-2). Otherwise, the legacy step size is applied.

[0260] For a PRACH in a non-SBFD symbol, the PRACH power of the PRACH is determined as follows: Specifically, the PRACH power of the PRACH (PREAMBLE_RECEIVED_TARGET_POWER) may be represented by preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA + POWER_OFFSET_SBFD_RA.

[0261] For example, the preambleReceivedTargetPower included in the legacy RACH configuration is applied as the preambleReceivedTargetPower.

[0262] For example, the powerRampingStep included in the legacy RACH setting is applied as the powerRampingStep.

[0263] For example, POWER_OFFSET_SBFD_RA may be set according to the following formula:

[0264] POWER_OFFSET_SBFD_RA = (PREAMBLE_POWER_RAMPING_COUNTER - 1) × (SBFD_PREAMBLE_POWER_RAMPING_STEP - PREAMBLE_POWER_RAMPING_STEP) Here, for SBFD_PREAMBLE_POWER_RAMPING_STEP, if the powerRampingStep included in the RACH configuration for SBFD or the sbfd-powerRampingStep included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-2). Otherwise, the legacy step size is applied.

[0265] (4.3.5.3) Operation Example 5-2 In Operation Example 5-2, switching from a first type of unit time (non-SBFD symbols) to a second type of unit time (SBFD symbols) is determined based on a second condition. Switching may be interpreted as fallback. The second condition is that the number of RACH attempts in SBFD symbols and / or non-SBFD symbols reaches a certain number. The certain number may be interpreted as a threshold. The following options are possible for Operation Example 5-2.

[0266] In operation example 5-2, the second condition may be that the number of RACH attempts in non-SBFD symbols reaches a certain number. As operation example 5-2, the following options are considered.

[0267] Option 5-2-1 sets the threshold for switching from non-SBFD symbols to SBFD symbols.

[0268] For example, the threshold may be preambleTransMax included in an additional / separate RACH configuration (RACH configuration for SBFD), and may be used to determine whether to switch from non-SBFD symbols to SBFD symbols.

[0269] For example, the threshold may be a new parameter (e.g., sbfd-TransMax) included in the legacy RACH configuration or the RACH configuration for SBFD, and may be used to determine whether to switch from a non-SBFD symbol to an SBFD symbol.

[0270] The UE 200 may assume that the threshold is less than or not greater than the preambleTransMax included in the legacy RACH configuration.

[0271] In option 5-2-2, the UE 200 may perform the following operations for switching from a non-SBFD symbol to an SBFD symbol, specifically, the case where the first RACH attempt is a PRACH transmission in a non-SBFD symbol will be described.

[0272] 17, UE 200 determines to transmit a PRACH in a non-SBFD symbol when PREAMBLE_TRANSMISSION_COUNTER is smaller than or not larger than a threshold (preambleTransMax or sbfd-TransMax). The PRACH in a non-SBFD symbol may be a PRACH in a valid RO in a non-SBFD symbol, or may be a PRACH in a valid RO configured by a legacy RACH configuration.

[0273] On the other hand, as shown in Fig. 17 , when PREAMBLE_TRANSMISSION_COUNTER is not greater than or less than a threshold (preambleTransMax or sbfd-TransMax), UE 200 determines to transmit a PRACH in an SBFD symbol. The PRACH in the SBFD symbol may be a PRACH in a valid RO in the SBFD symbol, or may be a PRACH in a valid RO configured by the RACH configuration for SBFD.

[0274] In option 5-2-2, when separate SSB lists are configured for SBFD and non-SBFD, UE 200 may select an SSB from the SSB list for SBFD.

[0275] Option 5-2-3 describes the power ramping counter (PRC). When switching from a non-SBFD symbol to an SBFD symbol, the value of the power ramping counter may be as follows:

[0276] In Alt. 1, the value of the power ramping counter may be reset to zero.

[0277] In Alt. 2, the value of the power ramping counter may be carried over without incrementing.

[0278] In Alt. 3, the value of the power ramping counter may be incremented by one and then carried over.

[0279] Option 5-2-4 describes the determination of transmission power, specifically, the case where the first RACH attempt is a PRACH transmission in a non-SBFD symbol.

[0280] For a RACH attempt (PRACH transmission) in a non-SBFD symbol, the PRACH power of the PRACH is determined as follows: Specifically, the PRACH power of the PRACH (PREAMBLE_RECEIVED_TARGET_POWER) may be represented by preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA.

[0281] For example, the preambleReceivedTargetPower included in the legacy RACH configuration is applied as the preambleReceivedTargetPower.

[0282] For example, the powerRampingStep included in the legacy RACH setting is applied as the powerRampingStep.

[0283] For a PRACH in an SBFD symbol, the PRACH power of the PRACH is determined as follows: Specifically, the PRACH power of the PRACH (PREAMBLE_RECEIVED_TARGET_POWER) may be represented by preambleReceivedTargetPower + DELTA_PREAMBLE + (PREAMBLE_POWER_RAMPING_COUNTER - 1) × PREAMBLE_POWER_RAMPING_STEP + POWER_OFFSET_2STEP_RA + POWER_OFFSET_SBFD_RA.

[0284] For example, for preambleReceivedTargetPower, if preambleReceivedTargetPower included in the RACH configuration for SBFD or sbfd-preambleReceivedTargetPower included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-1). Otherwise, the legacy target power is applied.

[0285] For example, for PREAMBLE_POWER_RAMPING_STEP, if the powerRampingStep included in the RACH configuration for SBFD or the sbfd-powerRampingStep included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-2). Otherwise, the legacy step size is applied.

[0286] For example, POWER_OFFSET_SBFD_RA may be set according to the following formula:

[0287] POWER_OFFSET_SBFD_RA = (PREAMBLE_POWER_RAMPING_COUNTER - 1) × (SBFD_PREAMBLE_POWER_RAMPING_STEP - PREAMBLE_POWER_RAMPING_STEP) Here, for SBFD_PREAMBLE_POWER_RAMPING_STEP, if the powerRampingStep included in the RACH configuration for SBFD or the sbfd-powerRampingStep included in the legacy RACH configuration or the RACH configuration for SBFD is configured, the configured parameter is applied (option 4-1-2). Otherwise, the legacy step size is applied.

[0288] (4.3.6) UE Capability In order to apply the above-mentioned operation examples 1 to 5, the following new UE capability and report signaling (and RRC settings) may be defined for each UE / FR / FC, etc.

[0289] Whether to support individual power control parameters for PRACH transmission in SBFD symbols Whether to support individual power control parameters for MsgA PUSCH transmission in SBFD symbols Whether to support switching between SBFD / non-SBFD symbols between PRACH transmission in the first RACH attempt and PRACH transmission in second or subsequent RACH retries Whether to support individual power ramping groups (power ramping counters (PRC)) for PRACH transmission in SBFD symbols and non-SBFD symbols Whether to support separate control parameters for PRACH in SBFD symbols (power ramping parameters) Whether to support parameters included in the RACH configuration for SBFD as control parameters for PRACH in SBFD symbols (power ramping parameters) Whether to support parameters included in the legacy RACH configuration as control parameters for PRACH in SBFD symbols (power ramping parameters) Whether to support switching from SBFD symbols to non-SBFD symbols Whether to support switching from non-SBFD symbols to SBFD symbols

[0290] (5) Actions and Effects According to the above-described embodiment, the UE 200 can perform power ramping in an RA retry, taking into consideration the difference between the symbol type in an RA attempt and the symbol type in an RA retry.

[0291] According to the above-described embodiment, UE 200 controls the transmission power of a preamble to be transmitted in a second-type unit time (SBFD symbol) to which SBFD is applied, based on a second control parameter that is defined separately from a first control parameter that does not assume SBFD and that assumes SBFD (Operation Example 4). Such a configuration clarifies what the second control parameter is, how to apply the second control parameter, and the like, and enables appropriate execution of RACH attempt / retry in SBFD symbols and non-SBFD symbols.

[0292] According to the above-described embodiment, the UE 200 determines whether to perform switching between non-SBFD symbols and SBFD symbols in a RACH attempt or a RACH retry based on a condition (Operation Example 5). With this configuration, a condition for determining whether to perform switching between SBFD symbols and non-SBFD symbols is introduced, making it possible to appropriately perform a RACH attempt / retry in SBFD symbols and non-SBFD symbols.

[0293] (6) Other Embodiments The contents of the present invention have been described above in accordance with the embodiments, but it will be obvious to those skilled in the art that the present invention is not limited to these descriptions and that various modifications and improvements are possible.

[0294] In the above-described operation example, the PRC is counted by one, but this is not limited to this. For example, two conditions may be set for the application of power ramping, and the PRC may be counted by one when one condition is satisfied, and the PRC may be counted by two when the other condition is satisfied. Note that the "condition" referred to here may be interpreted as the condition described in the operation example, or may be interpreted as another condition (e.g., whether the UE 200 is present at the cell edge or not).

[0295] The above-described operation examples may be combined and applied in a composite manner, as long as no contradiction occurs.

[0296] The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of hardware and / or software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (e.g., wired, wireless, etc.) and these multiple devices. The functional block may also be realized by combining software with the single device or multiple devices.

[0297] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0298] For example, the base station 100, the terminal 200, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 18 is a diagram illustrating an example of the hardware configuration of the base station 100 and the terminal 200 according to an embodiment of the present disclosure. The base station 100 and the terminal 200 described above may 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, etc.

[0299] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of base station 100 and terminal 200 may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0300] Each function in the base station 100 and the terminal 200 is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and the memory 1002, causing the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of reading and writing data in the memory 1002 and the storage 1003.

[0301] The processor 1001 controls the entire computer by running, for example, an operating system, and may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control unit, an arithmetic unit, a register, etc.

[0302] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002 and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. While the above-described various processes have been described as being executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may be transmitted from a network via a telecommunications line.

[0303] The memory 1002 is a computer-readable recording medium and may be configured by, for example, at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to one embodiment of the present disclosure.

[0304] Storage 1003 is a computer-readable recording medium and may be, for example, at least one of an optical disk such as a Compact Disc ROM (CD-ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. Storage 1003 may also be referred to as an auxiliary storage device. The above-mentioned storage medium may be, for example, a database, a server, or other suitable medium including at least one of memory 1002 and storage 1003.

[0305] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize, for example, at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

[0306] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, an LED lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0307] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0308] Furthermore, base station 100 and terminal 200 may 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), and some or all of the functional blocks may be realized by the hardware. For example, processor 1001 may be implemented using at least one of these pieces of hardware.

[0309] The notification of information is not limited to the aspects / embodiments described in the present disclosure and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling), broadcast information (Master Information Block (MIB), System Information Block (SIB)), other signals, or a combination thereof. Furthermore, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0310] Each aspect / embodiment described in this disclosure may apply to at least one of a system using Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, a 4th generation mobile communication system (4G), a 5th generation mobile communication system (5G), a 6th generation mobile communication system (6G), an xth generation mobile communication system (xG) (where x is, for example, an integer or a decimal), Future Radio Access (FRA), New Radio (NR), New radio access (NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or any other suitable system, and next generation systems extended, modified, created, or defined based on these. In addition, multiple systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A with 5G).

[0311] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0312] In the present disclosure, a specific operation described as being performed by a base station may be performed by its upper node in some cases. In a network consisting of one or more network nodes having a base station, it is clear that various operations performed for communication with a terminal may be performed by at least one of the base station and another network node other than the base station (for example, an MME or an S-GW, etc., but are not limited to these). Although the above example illustrates a case where there is one other network node other than the base station, a combination of multiple other network nodes (for example, an MME and an S-GW) may also be used.

[0313] Information, signals (information, etc.) may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0314] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be transmitted to another device.

[0315] The determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0316] The aspects / embodiments described in this disclosure may be used alone, in combination, or switched depending on the implementation. Notification of predetermined information (e.g., notification that "X is true") is not limited to explicit notification, but may be implicit (e.g., not notifying the predetermined information).

[0317] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0318] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0319] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0320] Note that terms described in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0321] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0322] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0323] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may 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 way.

[0324] In this disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0325] A base station can accommodate one or more (e.g., three) cells (also called sectors). When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can be provided with communication services by a base station subsystem (e.g., a small indoor base station (Remote Radio Head, RRH)). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or a base station subsystem that provides communication services within this coverage.

[0326] In the present disclosure, the base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control or operate based on the information.

[0327] In this disclosure, terms such as "terminal," "user terminal," "Mobile Station (MS)," and "User Equipment (UE)" may be used interchangeably.

[0328] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0329] At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, the mobile object itself, etc. The mobile object refers to a movable object, and may move at any speed. Naturally, this also includes cases where the mobile object is stationary. Examples of the mobile object include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and objects mounted thereon. The mobile object may also be an autonomous mobile object operating based on an operational command. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

[0330] Furthermore, the base station in the present disclosure may be read as a terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a terminal is replaced with communication between multiple terminals (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the terminal 200 may be configured to have the functions of the base station 100 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0331] Similarly, the term "terminal" in the present disclosure may be read as "base station." In this case, the base station 100 may be configured to have the functions of the terminal 200 described above.

[0332] 19 shows an example of the configuration of a vehicle 2001. As shown in Fig. 19, the vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, left and right front wheels 2007, left and right rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013.

[0333] The drive unit 2002 is composed of, for example, an engine, a motor, or a hybrid of an engine and a motor.

[0334] The steering unit 2003 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel operated by the user.

[0335] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals are input to the electronic control unit 2010 from various sensors 2021 to 2027 provided in the vehicle. The electronic control unit 2010 may also be called an Electronic Control Unit (ECU).

[0336] The signals from the various sensors 2021 to 2029 include a current signal from a current sensor 2021 that senses the current of the motor, a rotation speed signal of the front and rear wheels obtained by a rotation speed sensor 2022, an air pressure signal of the front and rear wheels obtained by an air pressure sensor 2023, a vehicle speed signal obtained by a vehicle speed sensor 2024, an acceleration signal obtained by an acceleration sensor 2025, an accelerator pedal depression amount signal obtained by an accelerator pedal sensor 2029, a brake pedal depression amount signal obtained by a brake pedal sensor 2026, a shift lever operation signal obtained by a shift lever sensor 2027, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 2028.

[0337] The information service unit 2012 is composed of various devices, such as a car navigation system, an audio system, speakers, a television, and a radio, for providing (outputting) various types of information, such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 2012 uses information acquired from external devices via the communication module 2013, etc., to provide various types of multimedia information and multimedia services to the occupants of the vehicle 2001.

[0338] The information service unit 2012 may include input devices (e.g., keyboards, mice, microphones, switches, buttons, sensors, touch panels, etc.) that accept input from the outside, and may also include output devices (e.g., displays, speakers, LED lamps, touch panels, etc.) that output to the outside.

[0339] The driving assistance system unit 2030 is composed of various devices that provide functions for preventing accidents and reducing the driver's driving burden, such as millimeter-wave radar, Light Detection and Ranging (LiDAR), cameras, positioning locators (e.g., GNSS, etc.), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., inertial measurement units (IMUs), inertial navigation systems (INSs), etc.), artificial intelligence (AI) chips, and AI processors, as well as one or more ECUs that control these devices. The driving assistance system unit 2030 also transmits and receives various information via the communication module 2013 to realize driving assistance functions or autonomous driving functions.

[0340] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via the communication port. For example, the communication module 2013 transmits and receives data via the communication port 2033 to and from the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, left and right front wheels 2007, left and right rear wheels 2008, axle 2009, microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021 to 2029, which are provided in the vehicle 2001.

[0341] The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station, a mobile station, or the like.

[0342] The communication module 2013 may transmit at least one of signals from the above-mentioned various sensors 2021 to 2029 input to the electronic control unit 2010, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 2012 to an external device via wireless communication. The electronic control unit 2010, the various sensors 2021 to 2029, the information service unit 2012, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above-mentioned input.

[0343] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from external devices and displays it on the information service unit 2012 provided in the vehicle. The information service unit 2012 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH received by the communication module 2013 (or data / information decoded from the PDSCH)).

[0344] Furthermore, the communication module 2013 stores various information received from external devices in a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, left and right front wheels 2007, left and right rear wheels 2008, axle 2009, sensors 2021 to 2029, and the like provided in the vehicle 2001.

[0345] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching a table, database, or other data structure), and ascertaining, all of which are considered to be "judging" and "determining." "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, and accessing (e.g., accessing data in memory), all of which are considered to be "judging" and "determining." "Determining" and "determining" may also include resolving, selecting, choosing, establishing, comparing, and other actions, all of which are considered to be "judging" and "determining." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Also, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0346] The terms "connected," "coupled," or any variation 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 two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0347] The reference signal may also be abbreviated as RS, and may be called a pilot depending on the applicable standard.

[0348] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0349] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0350] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0351] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0352] A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0353] Numerology may be a communication parameter applied to the transmission and / or reception of a signal or channel, such as subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by the transceiver in the frequency domain, specific windowing operations performed by the transceiver in the time domain, etc.

[0354] A slot may consist of one or more symbols in the time domain (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.) A slot may be a time unit based on numerology.

[0355] A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0356] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0357] For example, one subframe may be referred to as a transmission time interval (TTI), multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1 to 13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be referred to as a slot, minislot, etc., instead of a subframe.

[0358] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station schedules each terminal by allocating radio resources (such as frequency bandwidth and transmission power that can be used by each terminal) in TTI units. However, the definition of TTI is not limited to this.

[0359] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0360] In addition, when one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit for scheduling. Furthermore, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0361] A TTI having a time length of 1 ms may be referred to as a regular TTI (TTI in LTE Rel. 8 to 12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be referred to as a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0362] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0363] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may be determined based on numerology.

[0364] The time domain of an RB may include one or more symbols and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0365] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

[0366] 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.

[0367] A Bandwidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0368] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0369] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

[0370] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples, and various configurations, such as the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, and the cyclic prefix (CP) length, can be changed.

[0371] The "maximum transmit power" in this disclosure may mean the maximum value of transmit power, the nominal UE maximum transmit power, or the rated UE maximum transmit power.

[0372] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0373] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0374] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

[0375] (Additional Note) The above disclosure may be expressed as follows.

[0376] A first feature of the present invention is a terminal including: a transmitting unit that transmits a preamble that starts random access in a time unit in which time division duplexing is applied; and a control unit that performs power ramping that increases the transmission power of the preamble in attempts and retries of the random access, wherein the control unit controls the transmission power of the preamble that is transmitted in a first type of unit time in which the duplexing method is not applied, based on a first control parameter that does not assume a duplexing method that allows simultaneous use of multiple subbands in the time unit in which time division duplexing is applied; and controls the transmission power of the preamble that is transmitted in a second type of unit time in which the duplexing method is applied, based on a second control parameter that assumes the duplexing method.

[0377] Feature 1-2 is the terminal according to feature 1-1, wherein the second control parameter includes at least one of a parameter related to a target power of the preamble, a parameter related to a step size for increasing the transmission power of the preamble, and a parameter related to a maximum number of times the preamble is transmitted.

[0378] Feature 1-3 is a terminal in which, in feature 1-1 or feature 1-2, when switching between the first type unit time and the second type unit time is not supported in the random access attempt and retry, if the second control parameter is set, the control unit controls the transmission power of the preamble to be transmitted in the second type unit time based on the second control parameter, and if the second control parameter is not set, the control unit controls the transmission power of the preamble to be transmitted in the second type unit time based on the first control parameter.

[0379] Feature 1-4 is a terminal in which, in feature 1-1 or feature 1-2, when switching between the first type unit time and the second type unit time is supported in attempting and retrying the random access, the control unit controls the transmission power of the preamble depending on whether the number of times the preamble is transmitted between the first type unit time and the second type unit time is counted jointly or separately.

[0380] Feature 1-5 is the terminal according to feature 1-4, wherein, when the number of times the preamble is transmitted is counted separately, the control unit controls the transmission power of the preamble based on both of the separately counted numbers of transmissions.

[0381] Feature 2-1 is a terminal that includes a transmitting unit that transmits a preamble that starts random access in a time unit in which time division duplexing is applied, and a control unit that performs power ramping that increases the transmission power of the preamble in an attempt and a retry of the random access, and the control unit determines, based on conditions, whether to switch between a first type of unit time in which a duplexing method that allows simultaneous use of multiple subbands is not applied and a second type of unit time in which the duplexing method is applied in an attempt and a retry of the random access.

[0382] A feature 2-2 is the terminal according to the feature 2-1, wherein the control unit determines switching from the second type unit time to the first type unit time based on a first condition.

[0383] Feature 2-3 is the terminal according to feature 2-2, wherein the first condition is defined by a parameter related to a threshold that is compared with the number of times the preamble is transmitted in the second type unit time.

[0384] Feature 2-4 is a terminal in which, in at least one of features 2-1 to 2-3, the control unit determines switching from the first type of unit time to the second type of unit time based on a second condition.

[0385] Feature 2-5 is the terminal according to feature 2-4, wherein the second condition is defined by a parameter related to a threshold that is compared with the number of times the preamble is transmitted in the second type unit time.

[0386] 10 Wireless communication system 20 NG-RAN 100 Base station 110 Wireless signal transmitting / receiving unit 120 Control unit 200 Terminal 210 Wireless signal transmitting / receiving unit 220 Amplifier unit 230 Modulation / demodulation unit 240 Control signal / reference signal processing unit 250 Encoding / decoding unit 260 Data transmitting / receiving unit 270 Control unit 1001 Processor 1002 Memory 1003 Storage 1004 Communication device 1005 Input device 1006 Output device 1007 Bus 2001 Vehicle 2002 Drive unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever 2007 Left and right front wheels 2008 Left and right rear wheels 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 RPM sensor 2023 Air pressure sensor 2024 Vehicle speed sensor 2025 Acceleration sensor 2026 Brake pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030 Driving assistance system section 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port (IO port)

Claims

1. A terminal comprising: a transmitting unit that transmits a preamble that initiates random access in a time unit in which time division duplexing is applied; and a control unit that performs power ramping to increase the transmission power of the preamble in an attempt and retry of the random access, wherein the control unit determines, based on conditions, whether or not to switch between a first type of unit time in which a duplexing method that allows simultaneous use of multiple subbands is not applied and a second type of unit time in which the duplexing method is applied in the attempt and retry of the random access.

2. The terminal according to claim 1, wherein the control unit determines switching from the second type of unit time to the first type of unit time based on a first condition.

3. The terminal according to claim 2, wherein the first condition is defined by a parameter relating to a threshold that is compared with the number of transmissions of the preamble in the second type of unit time.

4. The terminal according to claim 1, wherein the control unit determines switching from the first type of unit time to the second type of unit time based on a second condition.

5. The terminal according to claim 4, wherein the second condition is defined by a parameter relating to a threshold value to be compared with the number of transmissions of the preamble in the first type of unit time.

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