Patent Description:
NOKIA ET AL: "On <NUM>-step RACH procedure", R1-<NUM>, discloses the <NUM>-step RACH procedure, considering the following aspects: Overview of the <NUM>-step RACH procedure, MsgA time alignment, MsgB design and HARQ Operation.

ANONYMOUS, "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; Physical layer procedures for control (Release <NUM>)", vol. RAN WG1, no. <NUM>, discusses physical uplink control channel and UE behaviour.

In some aspects, a method of wireless communication, performed by a user equipment (UE), according to claim <NUM> is disclosed.

In some aspects, an apparatus for wireless communication according to claims <NUM> is disclosed.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and/or processing system as substantially described herein with reference to and as illustrated by the accompanying drawings and specification.

The wireless network <NUM> may include a number of BSs <NUM> (shown as BS 110a, BS 110b, BS 110c, and BS 11od) and other network entities.

Controller/processor <NUM> of base station <NUM>, controller/processor <NUM> of UE <NUM>, and/or any other component(s) of <FIG> may perform one or more techniques associated with power control for a HARQ ACK feedback signal in random access, as described in more detail elsewhere herein. For example, controller/processor <NUM> of base station <NUM>, controller/processor <NUM> of UE <NUM>, and/or any other component(s) of <FIG> may perform or direct operations of, for example, process <NUM> of <FIG> and/or other processes as described herein. Memories <NUM> and <NUM> may store data and program codes for base station <NUM> and UE <NUM>, respectively. In some aspects, memory <NUM> and/or memory <NUM> may comprise a non-transitory computer-readable medium storing one or more instructions for wireless communication. For example, the one or more instructions, when executed by one or more processors of the base station <NUM> and/or the UE <NUM>, may perform or direct operations of, for example, process <NUM> of <FIG> and/or other processes as described herein.

The UE <NUM> includes means for receiving a response message associated with a random access message, wherein the response message includes an identifier of the UE; means for selecting a format of an uplink channel or an uplink signal for acknowledging successful decoding of the response message; means for determining a transmit power for hybrid automatic repeat request (HARQ) acknowledgment (ACK) information; means for transmitting the HARQ ACK information using a power control procedure based at least in part on the transmit power and the identifier; means for receiving a transmit power control command in at least one of: downlink control information (DCI) carried by a downlink control channel of the response message, or a success random access response carried by a downlink shared channel of the response message; means for receiving signaling indicating a configuration for at least one of a power control mode or a power control parameter for determining the transmit power; and/or the like. In some aspects, such means may include one or more components of UE <NUM> described in connection with <FIG>, such as controller/processor <NUM>, transmit processor <NUM>, TX MIMO processor <NUM>, MOD <NUM>, antenna <NUM>, DEMOD <NUM>, MIMO detector <NUM>, receive processor <NUM>, and/or the like.

A UE may use a random access procedure to access a cell. For example, the random access procedure may include a two-step random access procedure, a four-step random access procedure, and/or the like. In NR, a two-step random access procedure can be used for contention-based random access (CBRA) and for contention-free random access (CFRA). For example, CBRA may be usable in any RRC state (e.g., idle, inactive, or connected), whereas CFRA may be usable in an RRC connected state.

In some cases, a UE may initiate a two-step random access procedure by transmitting a random access message, such as random access channel (RACH) Message A. The two-step random access procedure may proceed differently depending on an outcome of a base station's processing of the random access message. For example, the base station may transmit a success random access response (RAR), a fallback RAR, or a backoff indicator in a response message depending on an outcome of processing of a preamble and/or a payload of the random access message. For example, the base station may provide the success RAR, the fallback RAR, or the backoff indicator in a response message such as a RACH Message B.

The UE may retransmit the payload and/or the preamble of the random access message (e.g., may reattempt the two-step random access process or fall back to the four-step random access procedure) if the UE does not receive a success RAR. The base station may respond with a success RAR or a fourth message of a four-step random access procedure if the base station can decode the retransmitted preamble and/or payload. If the UE successfully decodes the success RAR or the fourth message, then the UE may transmit HARQ ACK information to complete the random access procedure.

The HARQ ACK information can be mapped to multiple different uplink physical channels or physical signals, which may be associated with different signaling overhead and reliability. Furthermore, the transmission of the HARQ ACK information may introduce inter-cell or intra-cell interference and may use UE battery power. Thus, a single or inflexible approach to transmit power determination for the HARQ ACK information may increase interference and UE battery power usage.

Some techniques and apparatuses described herein provide power control for HARQ ACK information associated with a random access procedure. For example, some techniques and apparatuses described herein provide for mapping of the HARQ ACK information to one or more bits. Some techniques and apparatuses described herein provide open loop power control or closed loop power control for the HARQ ACK information. For example, a power control formula based at least in part on a bandwidth, carrier, cell, and transmit occasion of the HARQ ACK information is provided herein. The power control may be further based at least in part on a format of an uplink channel or uplink signal used for the HARQ ACK information, a message type of the response message, a mode of random access associated with the response message, a power control configuration used for determining the transmit power, and/or the like. In this way, inter-cell and intra-cell interference may be reduced and UE power utilization may be improved.

<FIG> is a diagram illustrating an example <NUM> of HARQ ACK transmit power determination for a two-step random access procedure, in accordance with various aspects of the present disclosure. As shown, example <NUM> includes a UE <NUM> and a BS <NUM>.

As shown by reference number <NUM>, the BS <NUM> may provide a synchronization signal block and random access channel (RACH) configuration information to the UE <NUM>. The RACH configuration information may identify a configuration for a two-step RACH procedure. In some aspects, the RACH configuration information may identify a power control parameter. For example, the power control parameter may be different for a CBRA than for a CFRA. In some aspects, the RACH configuration information may include an indication of whether a response message is to use a physical uplink control channel (PUCCH), uplink control information (UCI) multiplexed with a physical uplink shared channel (PUSCH), an uplink reference signal, and/or the like. In some aspects, the RACH configuration information may indicate a format for a response message (e.g., a long PUCCH format, a short PUCCH format, and/or the like). In some aspects, the RACH configuration information may indicate a bandwidth part, an uplink carrier, a numerology, a reference index for pathloss measurement, and/or the like. In some aspects, the RACH configuration information may indicate a random access preamble index allocated for the UE in a CFRA procedure.

As shown by reference number <NUM>, the UE <NUM> may transmit, and the base station <NUM> may receive, a random access message of a two-step random access procedure (e.g., RACH MsgA or Message A). For example, the UE <NUM> may transmit the random access message in accordance with the RACH configuration information received in connection with reference number <NUM>. The random access message may include a preamble and a payload (e.g., a PUSCH). The BS <NUM> may perform different actions based on whether the BS <NUM> successfully decodes one or more of the preamble and the payload. In some aspects, the UE <NUM> may transmit the preamble and/or the payload with a particular power control configuration, which is described in more detail elsewhere herein.

As shown by reference number <NUM>, in example <NUM>, the BS <NUM> successfully decodes the payload and the preamble. For an example of when the BS <NUM> detects only the preamble and not the payload, refer to <FIG>. If the BS <NUM> fails to decode the preamble, then the BS <NUM> may perform no action and the UE <NUM> may retransmit the message shown by reference number <NUM>. In example <NUM>, the BS <NUM> may detect the preamble, identify the payload based at least in part on the preamble, and decode the payload. As shown by reference number <NUM>, the BS <NUM> transmits a response message associated with the random access message shown by reference number <NUM>. Here, the response message includes a two-step random access procedure MsgB success random access response (RAR) based at least in part on the BS <NUM> successfully decoding the preamble and the payload.

As further shown, the response message includes an identifier of the UE <NUM>. For example, the identifier may be a unique identifier of the UE <NUM>. In some aspects, the identifier may include an inactive state radio network temporary identifier (RNTI), an idle state RNTI, a cell-specific RNTI, a random access preamble index (RAPID) allocated for the UE in a CFRA procedure, and/or the like. The UE <NUM> may provide HARQ ACK information based at least in part on identifying the identifier in the response message, as described in more detail below.

As shown by reference number <NUM>, the UE <NUM> may determine a transmit power for HARQ ACK information. For example, the UE <NUM> may successfully decode the response message, and may accordingly provide HARQ ACK information indicating that the response message was successfully decoded, thereby completing the random access procedure. Techniques and apparatuses described herein provide for determination of a transmit power and/or a power control procedure for transmission of the HARQ ACK information, thereby improving UE power utilization and reducing inter-cell interference and intra-cell interference.

The UE <NUM> determines the transmit power based at least in part on a power control configuration. In some aspects, power control parameters associated with the power control configuration may be indicated in system information (SI) (e.g., for inactive or idle UEs), radio resource control (RRC) signaling (e.g., for connected UEs), using a lookup table associated with two-step RACH, and/or the like. For example, the UE <NUM> may receive signaling indicating a configuration for at least one of power control mode (e.g., open loop power control, closed loop power control, and/or the like), or a power control parameter (described in more detail below in connection with Formula <NUM>). In such a case, an index of the lookup table may be indicated to the UE <NUM> in system information, such as a system information block.

In some aspects, the UE <NUM> may perform a power control procedure, such as an open loop power control procedure, a closed loop power control procedure, or a combination of an open loop power control procedure and a closed loop power control procedure, to determine the transmit power for the HARQ ACK information. In some aspects, the UE <NUM> may use the following Formula <NUM> to determine the HARQ ACK information (PHF,b,f,c(i, qd, l)): <MAT>.

In Formula <NUM>, b represents a bandwidth part, f represents a carrier, c represents a cell, and i represents a transmit occasion. A pathloss compensation value is represented by αb,f,c. A pathloss value at a reference signal index qd is represented by PLb,f,c(qd). A nominal UE transmit power is represented by Po_HF,b,f,c. An MCS-dependent offset is represented by ΔTF,b,f,c. A maximum transmit power of the UE <NUM> is represented by Pcmax,f,c(i). A dynamic offset is represented by gb,f,c(i,l). In some aspects, the dynamic offset may be defined by gb,f,c(i, l) = <MAT> and gb,f,c(<NUM>, l) = Δramp-up, b,f,c + δmsgB, b,f,c. Each of the above terms of Formula <NUM> is described in more detail below.

The pathloss compensation value (αb,f,c) may include a full pathloss compensation value (e.g., fully offsetting a pathloss of the HARQ ACK information) or a partial pathloss value (e.g., partially offsetting the pathloss of the HARQ ACK information). In some aspects, the pathloss compensation value may be based at least in part on the uplink channel or the uplink signal. For example, if the uplink channel is a PUCCH, then the pathloss compensation value may be a full pathloss compensation value. If the uplink channel is UCI piggybacked on a PUSCH, then the pathloss compensation value may be a full pathloss compensation value or a partial pathloss compensation value. In such a case, the pathloss compensation value may be based on a power control configuration of the PUSCH on which the UCI is piggybacked. If the uplink signal is an uplink reference signal, then the pathloss compensation value may be a full pathloss compensation value or a partial pathloss compensation value.

In some aspects, the nominal UE transmit power may be based at least in part on a previous nominal UE transmit power of the random access message (e.g., the random access message shown by reference number <NUM> or a transmission of a random access message before the random access message shown by reference number <NUM>). For example, the nominal UE transmit power may be based at least in part on the nominal UE transmit power of the preamble of the random access message or of the payload of the random access message. In some aspects, the nominal UE transmit power may be based at least in part on the previous nominal UE transmit power and based at least in part on an offset, such as a UE-specific offset. In some aspects, the nominal UE transmit power may be indicated using signaling, such as system information or radio resource control (RRC) signaling. In some aspects, the nominal UE transmit power may be based at least in part on an indicated value (e.g., using SI or RRC signaling) with an offset, such as a UE-specific offset.

The MCS-dependent offset (ΔTF, b, f, c) may take into account the MCS based at least in part on the transport format (TF) of the HARQ ACK information. In some aspects, the MCS-dependent offset may be set to a fixed value, such as zero. In some aspects, the MCS-dependent offset may follow a configuration rule for the physical channel or physical signal carrying the HARQ ACK. For example, for a HARQ ACK information provided using a piggybacked UCI, an offset (e.g., a semi-static offset) <MAT> may be configured (e.g., using RRC signaling and/or the like).

The dynamic offset (gb,f,c(i,l)) may be based at least in part on a sum of a power ramp-up for an open loop power control procedure and a transmit power control (TPC) accumulation for a closed loop power control procedure. This may be represented by <MAT> and gb,f,c(<NUM>, l) = Δramp-up, b,f,c + δmsgB, b,f,c. In some aspects, the size of the power ramp-up may use a power control configuration for a preamble or a payload of the random access message shown by reference number <NUM>. In some aspects, the size of the power ramp-up may be configured using SI, RRC signaling, a lookup table, and/or the like.

In some aspects, the UE <NUM> may use a bandwidth-dependent offset (not shown in the above formula) to determine the transmit power. For example, in some aspects, the bandwidth-dependent offset may be based at least in part on a numerology of the uplink channel or the uplink signal, a number of allocated resource blocks (RBs) of the uplink channel of the uplink signal, and/or the like. In some aspects, the bandwidth-dependent offset may be based at least in part on a scaling factor (e.g., a scaling factor applied to a value determined based at least in part on the numerology and the number of allocated RBs), which may be configured using SI, RRC, and/or the like.

As shown in the above formula, the UE <NUM> may use a pathloss value determined in accordance with a reference signal index and adjusted by the pathloss compensation value (αb,f,c × PLb,f,c(qd)). In some aspects, the reference signal index may refer to a preamble or a payload of the random access message shown by reference number <NUM>, or may be signaled to the UE <NUM> (e.g., using SI, RRC signaling, and/or the like) in a reference signal configuration.

In some aspects, the UE <NUM> may suspend a power ramping counter. For example, the UE <NUM> may suspend the power ramping counter based at least in part on a power control configuration for a preamble or a payload of the random access message shown by reference number <NUM>. As another example, the UE <NUM> may suspend the power ramping counter when the UE <NUM> changes a transmit spatial counter for transmission of the HARQ ACK information, when the UE <NUM> changes a bandwidth part, when the UE <NUM> changes an uplink carrier, or based at least in part on receiving DCI indicating to suspend the power ramping counter.

As shown by reference number <NUM>, the UE <NUM> transmits the HARQ ACK information (shown by reference number <NUM>) using a power control procedure and based at least in part on the transmit power determined in connection with reference number <NUM>. In some aspects, the power control procedure may be used to determine the transmit power. In some aspects, the transmit power may be used as part of the power control procedure.

In some aspects, the UE <NUM> may determine the transmit power and/or perform the power control procedure based at least in part on a TPC command. A TPC command may indicate that the UE <NUM> is to increment or decrement the transmit power. For example, the UE <NUM> may track TPC commands from the BS <NUM> in order to determine the transmit power. In some aspects, for open loop power control, TPC commands may be disabled. In some aspects, for closed loop power control, the TPC command may be carrier in DCI of a physical downlink control channel (PDCCH) of the MsgB success RAR shown by reference number <NUM>. In some aspects, the TPC command may be carried in a sub-protocol data unit (sub-PDU) of a physical downlink shared channel (PDSCH) of the MsgB success RAR shown by reference number <NUM>. In some aspects, the TPC command may be a UE-specific TPC command. In some aspects, the TPC command may be multicast to a group of UEs, including the UE <NUM>, as a group-common TPC command.

As shown by reference number <NUM>, the UE <NUM> transmits the HARQ ACK information. In some aspects, the HARQ ACK information may be mapped to a single bit. In some aspects, the HARQ ACK information may be mapped to multiple bits. For example, the multiple bits may include a repetition or coded sequence of the HARQ ACK information, or a multiplexing of the HARQ ACK information with another uplink transmission (e.g., a scheduling request, a beam management report, a channel state report, and/or the like). In some aspects, the HARQ ACK information may be mapped to a PUCCH, such as a PUCCH associated with a short PUCCH format or a long PUCCH format. In some aspects, the UE <NUM> and/or the BS <NUM> may determine the format of the uplink channel based at least in part on at least one of a waveform of the random access message (e.g., CP-OFDM or DFT-s-OFDM), a latency requirement of a random access procedure associated with the random access message, or a multiplexing capacity requirement of the UE <NUM>.

In some aspects, the HARQ ACK information may be mapped to UCI multiplexed with a PUSCH (e.g., by puncturing or rate matching the PUSCH). In some aspects, the HARQ ACK information may be mapped to an uplink reference signal, such as a sounding reference signal, a demodulation reference signal, a preamble, a sequence associated with a threshold peak to average power ratio, and/or the like. The usage of a signal having a threshold peak to average power ratio (e.g., a low peak to average power ratio) may improve performance of the signal by reducing degradation of the waveform.

<FIG> is a diagram illustrating an example <NUM> of HARQ ACK transmit power determination for a four-step random access procedure associated with a fallback from a two-step random access procedure, in accordance with various aspects of the present disclosure. Example <NUM> includes a UE <NUM> and a BS <NUM>. As shown in <FIG>, and by reference number <NUM>, example <NUM> is an example where the BS <NUM> detects only a preamble of the RACH Message A. In other words, in example <NUM>, the BS <NUM> fails to decode the payload of the RACH Message A.

As shown by reference number <NUM>, the BS <NUM> may transmit an indication that the BS <NUM> failed to decode the payload of the RACH Message A. Here, the indication includes a fallback RAR, such as a sub-PDU indicating that the UE <NUM> is to fall back to a four-step random access procedure. Accordingly, as shown by reference number <NUM>, the UE <NUM> retransmits the payload (e.g., the PUSCH) of the random access message using a message similar to Message <NUM> of the four-step random access procedure. As shown by reference number <NUM>, the BS <NUM> successfully decodes the retransmission (ReTX) of the payload. Accordingly, as shown by reference number <NUM>, the BS <NUM> transmits a response message (e.g., a RACH Message <NUM> of a four-step RACH procedure). As further shown, the response message includes an identifier of the UE <NUM>.

As shown by reference numbers <NUM> and <NUM>, the UE <NUM> may determine a transmit power for the HARQ ACK information, and may transmit the HARQ ACK information (shown by reference number <NUM>). The determination of the transmit power and the power control procedure are described in more detail in connection with reference numbers <NUM> and <NUM> of <FIG>, above. It should be understood that references to determination of the transmit power or the power control procedure based at least in part on the random access message shown by reference number <NUM> can also apply to the determination of the transmit power or the power control procedure for transmission of the HARQ ACK information <NUM> based at least in part on the MsgA shown in <FIG>.

<FIG> is a diagram illustrating an example process <NUM> performed, for example, by a UE, in accordance with various aspects of the present disclosure. Example process <NUM> is an example where the UE (e.g., UE <NUM> and/or the like) performs operations associated with power control for a HARQ feedback signal in random access.

As shown in <FIG>, in some aspects, process <NUM> includes receiving a response message associated with a random access message, wherein the response message includes an identifier of the UE (block <NUM>). For example, the UE (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may receive a response message associated with a random access message, as described above. In some aspects, the response message includes an identifier of the UE.

As further shown in <FIG>, in some aspects, process <NUM> includes selecting a format of an uplink channel or an uplink signal for acknowledging successful decoding of the response message (block <NUM>). The UE (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) selects a format of an uplink channel or an uplink signal for acknowledging successful decoding of the response message, as described above. The format may include, for example a PUCCH format, an uplink reference signal format, a UCI piggybacked on a PUSCH format, and/or the like. In some aspects, process <NUM> may not include selecting the format of the uplink channel or the uplink signal.

As further shown in <FIG>, process <NUM> includes determining a transmit power for HARQ ACK information based at least in part on at least one of: a message type of the response message, a mode of random access associated with the random access message, a power control configuration used by a previous transmission of the random access message, or the format of the uplink channel or the uplink signal (block <NUM>). The user equipment (UE) (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) determines a transmit power for hybrid automatic repeat request (HARQ) acknowledgment (ACK) information based at least in part on at least one of a message type of the response message, a mode of random access associated with the random access message (e.g., a two-step mode, a four-step fallback mode, and/or the like), a power control configuration used by a previous transmission of the random access message (e.g., random access message <NUM>, a previous transmission of a random access message before random access message <NUM>, and/or the like), or the format of the uplink channel or the uplink signal, as described above.

As further shown in <FIG>, process <NUM> includes transmitting the HARQ ACK information using a power control procedure based at least in part on the transmit power and based at least in part on the identifier (block <NUM>). For example, the user equipment (UE) (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may transmit the HARQ ACK information using a power control procedure based at least in part on the transmit power and the identifier, as described above.

In a first aspect, the message type of the response message comprises at least one of: a success random access response of a two-step random access procedure, or a RACH Message <NUM> of a four-step random access procedure.

In a second aspect, alone or in combination with the first aspect, the HARQ ACK information indicates that the response message was successfully decoded and the identifier was detected.

In a third aspect, alone or in combination with one or more of the first and second aspects, the identifier comprises at least one of: an inactive or idle state radio network temporary identifier (RNTI), a cell-specific RNTI, or a random access preamble index (RAPID) allocated for the UE in a contention free random access procedure.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the HARQ ACK information is mapped to a single bit.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the HARQ ACK information is mapped to multiple bits, and the multiple bits are associated with at least one of: a repetition or coded sequence of the HARQ ACK information, or a multiplexing of the HARQ ACK information with another uplink transmission.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the format of the uplink channel is determined based at least in part on at least one of: a waveform of the random access message, a latency requirement of a random access procedure associated with the random access message, or a multiplexing capacity requirement of the UE, and the uplink channel comprises a physical uplink control channel.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the HARQ ACK information is mapped to uplink control information (UCI) that is multiplexed with a physical uplink shared channel based at least in part on puncturing or rate matching the physical uplink shared channel.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the HARQ ACK information is mapped to an uplink reference signal.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the power control procedure is an open loop power control procedure, a configuration associated with the open loop power control procedure is based at least in part on a preamble or a payload of a previous transmission of the random access message.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the power control procedure is a closed loop power control procedure, and a configuration associated with the closed loop power control procedure is based at least in part on a preamble or a payload of a previous transmission of the random access message.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, process <NUM> includes receiving a transmit power control command in at least one of: downlink control information (DCI) carried by a downlink control channel of the response message, or a success random access response carried by a downlink shared channel of the response message.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, process <NUM> includes receiving signaling indicating a configuration for at least one of a power control mode or a power control parameter for determining the transmit power.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the signaling is carried by system information (SI) and radio resource control (RRC) signaling for a UE in a connected state.

In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the signaling is carried by radio resource control (RRC) signaling for a UE in a connected state.

In a fifteenth aspect, alone or in combination with one or more of the first through fourteenth aspects, determining the transmit power is based at least in part on whether the HARQ ACK information is mapped to a physical uplink control channel, uplink control information, or an uplink reference signal.

In a sixteenth aspect, alone or in combination with one or more of the first through fifteenth aspects, determining the transmit power is based at least in part on at least one of: whether a power ramping counter of the UE is suspended, whether a transmit power control (TPC) command is received, or whether a maximum transmit power of the UE is reached.

In a seventeenth aspect, alone or in combination with one or more of the first through sixteenth aspects, the power ramping counter of the UE is suspended based at least on at least one of: a change of a transmit spatial filter, a change of a bandwidth part, a change of an uplink carrier, or downlink control information received by the UE.

In an eighteenth aspect, alone or in combination with one or more of the first through seventeenth aspects, determining the transmit power is based at least in part on a nominal transmit power of the UE, wherein the nominal transmit power is based at least on at least one of: a nominal transmit power of a preamble of the previous transmission of the random access message, a nominal transmit power of a payload of the previous transmission of the random access message, a UE-specific offset, or a network-configured offset indicated by system information or radio resource control signaling.

In a nineteenth aspect, alone or in combination with one or more of the first through eighteenth aspects, determining the transmit power is based at least in part on an offset that is based at least in part on a modulation and coding scheme (MCS) of the UE, the offset is based at least in part on the format of the uplink channel or uplink signal carrying the HARQ ACK information.

In a twentieth aspect, alone or in combination with one or more of the first through nineteenth aspects, determining the transmit power is based at least in part on at least one of a power ramp-up procedure of the UE or an accumulation value associated with a transmit power control (TPC) command.

In a twenty first aspect, alone or in combination with one or more of the first through twentieth aspects, the TPC command comprises a UE-specific TPC command.

In a twenty second aspect, alone or in combination with one or more of the first through twenty first aspects, the TPC command is multicast to a group of UEs, including the UE, as a group-common TPC command.

In a twenty third aspect, alone or in combination with one or more of the first through twenty second aspects, determining the transmit power is based at least in part on a bandwidth of the uplink channel or the uplink signal.

In a twenty fourth aspect, alone or in combination with one or more of the first through twenty third aspects, determining the transmit power is based at least in part on a reference signal index configured for a pathloss measurement, wherein the reference signal index is based at least in part on at least one of: a reference signal index of a preamble or a payload of the previous transmission of the random access message, or a resource signal configuration of the UE.

In a twenty fifth aspect, alone or in combination with one or more of the first through twenty fourth aspects, the identifier is a unique identifier.

Claim 1:
A method of wireless communication performed by a user equipment, UE, comprising:
receiving (<NUM>) a response message associated with a random access message, wherein the response message includes an identifier of the UE;
selecting (<NUM>) a format of an uplink channel or an uplink signal for acknowledging successful decoding of the response message, wherein the format of the uplink channel is determined based at least in part on at least one of:
a waveform of the random access message,
a latency requirement of a random access procedure associated with the random access message, or
a multiplexing capacity requirement of the UE, and
wherein the uplink channel comprises a physical uplink control channel;
determining (<NUM>) a transmit power for hybrid automatic repeat request, HARQ, acknowledgment, ACK, information, wherein the HARQ ACK information indicates that the response message was successfully decoded and the identifier was detected,
wherein the transmit power is determined based at least in part on at least one of:
a message type of the response message,
a mode of random access associated with the random access message,
a power control configuration used by a previous transmission of the random access message, or
the format of the uplink channel or the uplink signal; and
transmitting (<NUM>) the HARQ ACK information using a power control procedure based at least in part on the transmit power and the identifier.