WO2022205431A1

WO2022205431A1 - Implicitly repeated initial transmission of msg3 pusch

Info

Publication number: WO2022205431A1
Application number: PCT/CN2021/085338
Authority: WO
Inventors: Jing Dai; Mahmoud Taherzadeh Boroujeni; Hung Dinh LY; Chao Wei; Qiaoyu Li; Gokul SRIDHARAN; Peter Gaal; Krishna Kiran Mukkavilli; Wanshi Chen
Original assignee: Qualcomm Incorporated
Priority date: 2021-04-02
Filing date: 2021-04-02
Publication date: 2022-10-06

Abstract

Certain aspects of the present disclosure provide a technique for wireless communications by a user equipment (UE). The UE implements the technique to send a random access channel (RACH) preamble to a network entity. The UE receives a random access response (RAR) message indicating a transmit power control (TPC) command value from the network entity. The UE sends an uplink message to the network entity in response to the RAR message. The uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and a rule.

Description

[Corrected under Rule 26, 01.03.2022] IMPLICITLY REPEATED INITIAL TRANSMISSION OF MSG3 PUSCH

INTRODUCTION

Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for an initial transmission of an uplink message (e.g., msg3) with a number of repetitions in response to a random access response (RAR) message (e.g., msg2) .

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcasts, or other similar types of services. These wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources with those users (e.g., bandwidth, transmit power, or other resources) . Multiple-access technologies can rely on any of code division, time division, frequency division orthogonal frequency division, single-carrier frequency division, or time division synchronous code division, to name a few. These and other multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level.

Although wireless communication systems have made great technological advancements over many years, challenges still exist. For example, complex and dynamic environments can still attenuate or block signals between wireless transmitters and wireless receivers, undermining various established wireless channel measuring and reporting mechanisms, which are used to manage and optimize the use of finite wireless channel resources. Consequently, there exists a need for further improvements in wireless communications systems to overcome various challenges.

SUMMARY

One aspect provides a method for wireless communications by a user equipment (UE) , including: sending, to a network entity, a random access channel (RACH) preamble; receiving, from the network entity, a random access response (RAR) message indicating a transmit power control (TPC) command value and a rule; and sending an uplink message to the network entity in response to the RAR message where the uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.

Another aspect provides a method for wireless communications by a network entity, including: receiving, from a UE, a RACH preamble; sending, to the UE, a RAR message indicating a TPC command value; and monitoring for an uplink message from the UE sent in response to the RAR message with a number of a number repetitions based on the TPC command value and a transmit power constraint of the UE.

Other aspects provide: an apparatus operable, configured, or otherwise adapted to perform the aforementioned methods as well as those described elsewhere herein; a non-transitory, computer-readable media comprising instructions that, when executed by one or more processors of an apparatus, cause the apparatus to perform the aforementioned methods as well as those described elsewhere herein; a computer program product embodied on a computer-readable storage medium comprising code for performing the aforementioned methods as well as those described elsewhere herein; and an apparatus comprising means for performing the aforementioned methods as well as those described elsewhere herein. By way of example, an apparatus may comprise a processing system, a device with a processing system, or processing systems cooperating over one or more networks.

The following description and the appended figures set forth certain features for purposes of illustration.

BRIEF DESCRIPTION OF THE DRAWINGS

The appended figures depict certain features of the various aspects described herein and are not to be considered limiting of the scope of this disclosure.

FIG. 1 is a block diagram conceptually illustrating an example wireless communication network.

FIG. 2 is a block diagram conceptually illustrating aspects of an example a base station (BS) and user equipment (UE) .

FIGS. 3A-3D depict various example aspects of data structures for a wireless communication network.

FIG. 4 depicts a call flow diagram for an example four step random access channel (RACH) procedure.

FIG. 5 depicts an example four slot physical uplink shared channel (PUSCH) .

FIG. 6 depicts example random access response (RAR) grant content.

FIG. 7 depicts an example table showing mapping between transmit power control (TPC) command values and power values.

FIG. 8 depicts a flow diagram illustrating example initial transmission operations of an uplink message for wireless communication by a UE.

FIG. 9 depicts a flow diagram illustrating example initial transmission operations of an uplink message for wireless communication by a network entity.

FIG. 10A depicts a call flow diagram illustrating example signaling for an initial transmission of an uplink message.

FIG. 10B depicts a call flow diagram illustrating example signaling for an initial transmission of an uplink message.

FIG. 10C depicts a call flow diagram illustrating example signaling for an initial transmission of an uplink message.

FIG. 11 depicts example transmit power for transmitting a RACH preamble and a transmit power constraint of a UE.

FIG. 12 depicts example transmit power used for transmitting RACH preamble, a transmission power level indicated by a TPC command value, and a transmit power constraint of a UE.

FIG. 13 depicts an example table showing a first mapping between TPC command values and power values.

FIG. 14 depicts an example table showing a second mapping between TPC command values and power values.

FIG. 15 depicts an example table showing mapping between a number of repetitions of an initial transmission of an uplink message and a transmit power level based on a power adjustment relative to a transmit power used for transmitting a RACH preamble.

FIG. 16 depicts example subcarrier spacing (SCS) for different UE capabilities.

FIG. 17 depicts example arrangement of non-consecutive slots for an initial transmission of an uplink message with a number of repetitions.

FIG. 18 depicts example uplink message resource usage.

FIG. 19 depicts aspects of an example communications device.

FIG. 20 depicts aspects of an example communications device.

DETAILED DESCRIPTION

Aspects of the present disclosure provide apparatuses, methods, processing systems, and computer-readable mediums for an initial transmission of an uplink message (e.g., msg3) with a number of repetitions, in response to a random access response (RAR) message (e.g., msg2) . For example, a user equipment (UE) may implicitly determine the number of repetitions for the initial transmission of a msg3 based on a transmit power control (TPC) command value indicated via the RAR message and other rules.

The techniques may allow a base station (e.g., a gNB) to implicitly indicate a number of repetitions a UE should use for the initial msg3 transmission, even in cases where it does not have sufficient information regarding the transmission power the UE used to transmit a RACH transmission. By indicating a transmission power adjustment value, the BS effectively allows the UE to decide whether to send msg3 with no repetition (if it has sufficient power headroom to apply the indicated power adjustment) or to send msg3 with repetition (if it lacks sufficient power headroom to apply the power adjustment) .

Introduction to Wireless Communication Networks

FIG. 1 depicts an example of a wireless communications system 100, in which aspects described herein may be implemented.

For example, wireless communication network 100 may include msg3 component 199, which may be configured to perform, or cause a base station (BS) 102 to perform, operations 900 of FIG. 9. Wireless communication network 100 may also include msg3 component 198, which may be configured to perform, or cause a user equipment (UE) 104 to perform, operations 800 of FIG. 8.

Generally, wireless communications system 100 includes BSs 102, UEs 104, one or more core networks, such as an Evolved Packet Core (EPC) 160 and 5G Core (5GC) network 190, which interoperate to provide wireless communications services.

BSs 102 may provide an access point to the EPC 160 and/or 5GC 190 for a UE 104, and may perform one or more of the following functions: transfer of user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity) , inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS) , subscriber and equipment trace, RAN information management (RIM) , paging, positioning, delivery of warning messages, among other functions. BSs 102 may include and/or be referred to as a gNB, NodeB, eNB, ng-eNB (e.g., an eNB that has been enhanced to provide connection to both EPC 160 and 5GC 190) , an access point, a base transceiver station, a radio base station, a radio transceiver, or a transceiver function, or a transmission reception point in various contexts.

BSs 102 wirelessly communicate with UEs 104 via communications links 120. Each of BSs 102 may provide communication coverage for a respective geographic coverage area 110, which may overlap in some cases. For example, small cell 102’ (e.g., a low-power BS) may have a coverage area 110’ that overlaps the coverage area 110 of one or more macrocells (e.g., high-power BSs) .

The communication links 120 between BSs 102 and UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to a BS 102 and/or downlink (DL) (also referred to as forward link) transmissions from a BS 102 to a UE 104. The communication links 120 may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity in various aspects.

Examples of UEs 104 include a cellular phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal digital assistant (PDA) , a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player, a camera, a game console, a tablet, a smart device, a wearable device, a vehicle, an electric meter, a gas pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor/actuator, a display, or other similar devices. Some of UEs 104 may be internet of things (IoT) devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, or other IoT devices) , always on (AON) devices, or edge processing devices. UEs 104 may also be referred to more generally as a station, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, or a client.

FIG. 2 depicts aspects of an example BS 102 and a UE 104 (e.g., in wireless communication network 100 of FIG. 1) .

Generally, BS 102 includes various processors (e.g., 220, 230, 238, and 240) , antennas 234a-t (collectively 234) , transceivers 232a-t (collectively 232) , which include modulators and demodulators, and other aspects, which enable wireless transmission of data (e.g., source data 212) and wireless reception of data (e.g., data sink 239) . For example, BS 102 may send and receive data between itself and UE 104.

BS 102 includes controller /processor 240, which may be configured to implement various functions related to wireless communications. In the depicted example, controller /processor 240 includes msg3 component 241, which may be representative of msg3 component 199 of FIG. 1. Notably, while depicted as an aspect of controller /processor 240, msg3 component 241 may be implemented additionally or alternatively in various other aspects of BS 102 in other implementations.

Generally, UE 104 includes various processors (e.g., 258, 264, 266, and 280) , antennas 252a-r (collectively 252) , transceivers 254a-r (collectively 254) , which include modulators and demodulators, and other aspects, which enable wireless transmission of data (e.g., source data 262) and wireless reception of data (e.g., data sink 260) .

UE 102 includes controller /processor 280, which may be configured to implement various functions related to wireless communications. In the depicted example, controller /processor 280 includes msg3 component 281, which may be representative of msg3 component 198 of FIG. 1. Notably, while depicted as an aspect of controller /processor 280, msg3 component 281 may be implemented additionally or alternatively in various other aspects of UE 104 in other implementations.

FIGS. 3A-3D depict aspects of data structures for a wireless communication network, such as wireless communication network 100 of FIG. 1. In particular, FIG. 3A is a diagram 300 illustrating an example of a first subframe within a 5G (e.g., 5G NR) frame structure, FIG. 3B is a diagram 330 illustrating an example of DL channels within a 5G subframe, FIG. 3C is a diagram 350 illustrating an example of a second subframe within a 5G frame structure, and FIG. 3D is a diagram 380 illustrating an example of UL channels within a 5G subframe.

Further discussions regarding FIG. 1, FIG. 2, and FIGS. 3A-3D are provided later in this disclosure.

Example Random Access Channel (RACH) Procedure

A user equipment (UE) (e.g., the UE 104 of FIG. 1 or FIG. 2) may access a wireless communication network (e.g., the wireless communication network 100 of FIG. 1) by negotiating a connection with a base station (BS) (e.g., the BS 102 of FIG. 1 or FIG. 2) included in the wireless communication network. During connection establishment, the UE and the BS may synchronize the connection in a downlink direction (i.e., from the BS to the UE) and in an uplink direction (i.e., from the UE to the BS) .

To synchronize the connection in the downlink direction, the UE reads a msg0 (e.g., a synchronization signal block (SSB) ) transmitted from the BS. The SSB includes various synchronization signals. The synchronization signals include a primary synchronization signal (PSS) , a secondary synchronization signal (SSS) , and/or the like. The UE uses the PSS to determine a symbol timing in the downlink direction. The UE uses the SSS to determine a physical cell identifier (PCI) associated with the BS and a frame timing.

To synchronize the connection in the uplink direction, the UE and the BS perform a random access channel (RACH) procedure. The RACH is so named because it refers to a wireless channel (medium) that may be shared by multiple UEs and used by the UEs to (randomly) access the wireless communication network for communications. The RACH is used for a call setup and to access the BS for data transmissions. In some cases, the RACH is used for an initial access to the BS when the UE switches from a radio resource control (RRC) connected idle mode to an active mode, or when handing over in a RRC connected mode.

As illustrated in FIG. 4, a UE and a BS exchange RACH communications. At 402, the UE sends a msg1 (RACH preamble) to the BS on a physical random access channel (PRACH) . The msg1 communication includes a RACH preamble communication. In some cases, the UE implicitly indicates some additional information to the BS as part of the msg1. The information may indicate a number of repetitions for a msg3 (in response to a msg2 communication) and/or a power headroom associated with the msg1.

At 404, the BS responds to the msg1 with the msg2, which is generally referred to as a random access response (RAR) communication. The RAR includes an identifier (ID) of the RACH preamble, a timing advance (TA) , an UL grant, a cell radio network temporary identifier (C-RNTI) , and/or a back off indicator. The msg2 includes a physical downlink control channel (PDCCH) communication including control information for a following communication on a physical downlink shared channel (PDSCH) . In some cases, the msg2 communication carries grant information for the msg3 communication. In some cases, the msg2 communication includes information associated with the number of repetitions for the msg3 communication.

At 406, the UE responds to the msg2 communication with the msg3 (which may be sent with an appropriate number of repetitions of the msg3 communication) on a physical uplink shared channel (PUSCH) . The msg3 communication may convey a RRC connection request communication.

At 408, the BS responds to the msg3 communication with a msg4 communication, which includes a medium access control -control element (MAC-CE) contention resolution message, an RRC setup command, and/or the like.

Example Msg3 PUSCH Scheduling

In some cases (such as in Rel-17 SI of coverage enhancement) , a physical uplink shared channel (PUSCH) (including msg3 PUSCH) is one of bottleneck channels for coverage enhancement. To address this challenge, repetition of the msg3 communication may be supported for a normal PUSCH (e.g., taking repetition Type A four slot PUSCH as illustrated in FIG. 5) . In some cases, a modulation and coding scheme (MCS) and a resource allocation are indicated in a scheduling downlink control information (DCI) that are common over successive slots of the PUSCH. For each slot of the multi slot PUSCH (as illustrated in FIG. 5) , a transmission block (TB) is same but encoded bits can differ (i.e. a redundancy version (RV) of each slot of the PUSCH may be different) .

In some cases, an initial transmission of a msg3 communication on a PUSCH (as opposed to a re-transmission requested if the initial msg3 fails) is scheduled based on a msg2 communication sent by a base station (BS) to a user equipment (UE) (e.g., with bit fields in a twenty seven bit random access response (RAR) grant content as illustrated in FIG. 6 where one RAR grant field indicates a transmit power control (TPC) command for a PUSCH and another RAR grant field indicates a reservation of a channel state information (CSI) request field) .

As illustrated in FIG. 7, a TPC command (indicated to a UE by a BS via a msg2 communication) corresponds to a (positive, negative, or zero) transmission power offset (in dB) with respect to a transmit power used for transmitting a msg1 communication from the UE to the BS.

However, at a time of scheduling an initial transmission of a msg3 communication via the msg2 communication, it is difficult for the BS to determine whether the UE needs a coverage enhancement. It may be even more difficult for the BS to determine how much coverage enhancement may be needed by the UE when the coverage enhancement is needed.

As a result, it is difficult for the BS to explicitly indicate to the UE whether the initial transmission of the msg3 communication may need a PUSCH slot repetition as well as a number of repetitions (when the PUSCH slot repetition is needed) . Also, if the BS always indicates a maximum number of repetitions of the msg3 communication that may be needed to the UE, it may cause wasteful power consumption of the UE as well as waste of network resources.

Accordingly, aspects of the present disclosure provide a technique to provide a UE with an appropriate number of repetitions for the msg3 communication that may not cause wasteful UE power consumption and also makes efficient use of network resources.

Aspects Related to Implicitly Repeated Initial Transmission of Msg3 PUSCH

Aspects of the present disclosure provide apparatuses, methods, processing systems, and computer-readable mediums for determining a number of repetitions for an initial transmission of an uplink message (e.g., msg3) implicitly based on information provided in a random access response (RAR) message (e.g., msg2) . For example, a user equipment (UE) may implicitly determine the number of repetitions for the initial transmission of a msg3 based on a transmit power control (TPC) command value indicated via the RAR message and other rules.

FIG. 8 depicts a flow diagram illustrating example operations 800 for wireless communication. The operations 800 may be performed, for example, by a UE (e.g., such as the UE 104 in the wireless communication network 100 of FIG. 1) . The operations 800 may be implemented as software components that are executed and run on one or more processors (e.g., the controller/processor 280 of FIG. 2) . Further, transmission and reception of signals by the UE in operations 800 may be enabled, for example, by one or more antennas (e.g., the antennas 252 of FIG. 2) . In certain aspects, the transmission and/or reception of signals by the UE may be implemented via a bus interface of one or more processors (e.g., the controller/processor 280) obtaining and/or outputting signals.

The operations 800 begin, at 810, by sending to a network entity a RACH preamble. For example, the UE may the RACH preamble to the network entity using antenna (s) and transmitter/transceiver components of the UE 104 shown in FIG. 1 or FIG. 2 and/or of the apparatus shown in FIG. 20.

At 820, the UE receives from the network entity a RAR message indicating a TPC command value and a rule. For example, the UE may receive the RAR message from the network entity using antenna (s) and receiver/transceiver components of the UE 104 shown in FIG. 1 or FIG. 2 and/or of the apparatus shown in FIG. 20.

At 830, the UE sends an uplink message to the network entity in response to the RAR message. For example, the uplink message may be sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule. The UE may send the uplink message to the network entity using antenna (s) and transmitter/transceiver components of the UE 104 shown in FIG. 1 or FIG. 2 and/or of the apparatus shown in FIG. 20.

FIG. 9 is a flow diagram illustrating example operations 900 for wireless communication. The operations 900 may be performed, for example, by a network entity (e.g., such as the BS 102 in the wireless communication network 100 of FIG. 1) . The operations 900 may be implemented as software components that are executed and run on one or more processors (e.g., the controller/processor 240 of FIG. 2) . Further, transmission and reception of signals by the network entity in operations 800 may be enabled, for example, by one or more antennas (e.g., the antennas 234 of FIG. 2) . In certain aspects, the transmission and/or reception of signals by the network entity may be implemented via a bus interface of one or more processors (e.g., the controller/processor 240) obtaining and/or outputting signals.

The operations 900 begin, at block 910, by receiving from a UE a RACH preamble. For example, the network entity may receive the RACH preamble from the UE using antenna (s) and receiver/transceiver components of the BS 102 shown in FIG. 1 or FIG. 2 and/or of the apparatus shown in FIG. 19.

At 920, the network entity sends to the UE a RAR message indicating a TPC command value and a rule. For example, the network entity may send the RAR message to the UE using antenna (s) and transmitter/transceiver components of the BS 102 shown in FIG. 1 or FIG. 2 and/or of the apparatus shown in FIG. 19.

At 930, the network entity monitors for an uplink message from the UE sent in response to the RAR message with a number of a number repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule. For example, the network entity may monitor the uplink message using antenna (s) and processor (s) of the BS 102 shown in FIG. 1 or FIG. 2 and/or of the apparatus shown in FIG. 19.

The operations shown in FIGs. 8 and 9 are further described with reference to FIGs. 10A-18.

As illustrated in FIG. 10A, at 1002, a UE (e.g., the UE 104 shown in FIG. 1 or FIG. 2) sends a RACH preamble (i.e. msg1 communication) to a BS (e.g., the BS 102 shown in FIG. 1 or FIG. 2) .

In certain aspects, the UE may convey an indication of a power headroom at the UE to the BS (e.g., by selection of RACH preamble or resource) . The power headroom indicates a difference between a transmit power constraint of the UE (i.e., P _CMAX as illustrated in FIG. 11 and/or a maximum power level for a PC3 UE as illustrated in FIG. 12) and a transmit power used for transmitting the RACH preamble (i.e., Tx power of preamble as illustrated in FIG. 11 and/or a RACH power level as illustrated in FIG. 12) . In one example, the UE indicates to the BS the indication of the power headroom via a RACH preamble sequence (e.g., different RACH preamble sequences may map to different power headroom values) . In another example, the UE sends to the BS the indication of the power headroom via a RACH transmission occasion (e.g., different RACH transmission occasions may map to different power headroom values) .

Referring back to FIG. 10A, at 1004, the BS uses the RACH preamble to determine a desired power level for a subsequent uplink message (i.e. msg3 communication) transmission from the UE. In some cases, the BS does not know a value of an exact transmit power the UE used for transmitting the RACH preamble, so the BS may only determine a desired power adjustment for the UE to apply to a subsequent uplink message (e.g., msg3) .

At 1006, the BS sends a RAR message (i.e. msg2 communication) indicating a transmit power control (TPC) command value corresponding to the desired power adjustment for msg3 (relative to the RACH preamble transmission) and a rule.

In certain aspects, in addition to the TPC command value, the BS also sends to the UE an indication of a maximum value for a number of repetitions for the uplink message (e.g. 2, 4) . In some cases, this maximum value may be sent via a system information block (SIB) . In certain aspects, the BS sends the indication of the maximum value for the number of repetitions for the uplink message to the UE via the RAR message. In some cases, when the maximum value for the number of repetitions for the uplink message is indicated to the UE via the RAR message, the UE interprets a reserved one bit channel state information (CSI) request field associated with the RAR message as the maximum value for the number of repetitions for the uplink message.

In certain aspects, the BS indicates a message corresponding to the desired power level (i.e., msg3 power level requested as illustrated in FIG. 12) for the subsequent uplink message transmission to the UE via the TPC command value. The TPC command value is indicated in a TPC field associated with the RAR message. In some cases, the desired power level is indicated as an offset on top of the transmit power used for transmitting the RACH preamble. In some cases, the message also indicates that there is no need to trigger repetition of the uplink message transmission until all transmit power level adjustment options associated with the initial transmission of the uplink message are exhausted.

In certain aspects, the BS also indicates a new table to the UE. The new table indicates a first mapping between TPC command values and power adjustment values (as illustrated in FIG. 13) , used to implicitly indicate repetitions for msg3 transmissions, that is different than a second mapping between TPC command values and power adjustment values (as illustrated in FIG. 14) used for other uplink transmissions. In certain aspects, when the new table is indicated to the UE, the RAR message also includes a bit that indicates to the UE to determine a power adjustment indicated by the TPC command value based on the first mapping.

In certain aspects, the rule may be predetermined and indicates an exact logic to determine the number of repetitions of the uplink message. In one example, the rule may indicate to the UE to not use all its transmission power (as per the transmit power constraint) for sending the uplink message and instead switch to sending repetitions of the uplink message once a threshold amount of the transmit power constraint is reached while sending the uplink message. In some cases, this may be motivated by uplink interference management.

Referring back to FIG. 10A, at 1008, the UE determines a number of repetitions of the uplink message from the UE to the BS based on the TPC command value, the rule, and the transmit power constraint of the UE. In one example, as illustrated in FIG. 15, the UE determines the number of repetitions of the uplink message based on a difference between a transmission power level (adjusted by applying a power adjustment indicated by the TPC command value relative to the transmit power used for transmitting the RACH preamble) and the transmit power constraint of the UE. In certain aspects, the UE determines the power adjustment indicated by the TPC command value based on the first mapping.

At 1010a-1010n, the UE sends the uplink message (msg3) with the determined number of repetitions (for a total of n msg3 transmissions in this example) of the uplink message (msg3) to the BS.

In certain aspects, when the transmission power level adjusted based on the power adjustment indicated by the TPC command value is less than or equal to the transmit power constraint of the UE, the number of repetitions of the uplink message is zero. In other words, in this case, the UE may have sufficient power headroom and may simply apply the power adjustment indicated in the TPC command and send a single msg3 with no repetition.

In certain aspects, as illustrated in FIG. 10B, prior to UE sending all the determined number of repetitions of the uplink message to the BS, at 1012, the BS sends an early termination indication to the UE. The early termination indication indicates to the UE to stop sending the uplink message (e.g., and that the BS has successfully decoded msg3) .

In one example, the BS sends the early termination indication to the UE via a downlink control information (DCI) (e.g., msg4 communication) (such as a DCI format 1_0 with a temporary cell radio network temporary identifier (TC-RNTI) ) . In some cases, the DCI schedules a subsequent downlink message or a retransmission of the uplink message.

In another example, the BS sends the early termination indication to the UE via a DCI (e.g., a uplink message retransmission scheduling DCI) (such as a DCI format 0_0 with a TC-RNTI) so that the uplink message retransmission acts as a repetition in scheduled resources other than in the initial transmission of the uplink message.

Referring back to FIG. 10B, at 1010, the UE terminates to send the uplink message early prior to sending all of the repetitions in response to receiving the early termination indication.

In certain aspects, the UE refrains from sending the repetitions of the uplink message that occur a threshold amount of time after receiving the DCI indicating the early termination indication (i.e., a minimum physical downlink control channel (PDCCH) to a terminated msg3 transmission gap is satisfied (e.g. N2 or N symbols in Rel-15/16) to allow a processing time needed for the DCI decoding and a cancellation of a msg3 physical uplink shared channel (PUSCH) transmission) . The threshold amount of time is determined based on a subcarrier spacing (SCS) , as illustrated in FIG. 16. In some cases, the threshold amount of time increases with the SCS.

In certain aspects, to allow processing time for the UE to early terminate sending of the uplink message prior to sending all of the repetitions based on the early termination indication, non-consecutive slots (i.e. slots with intervals) for repeated initial transmission of the uplink message are supported, as illustrated in FIG. 17.

In certain aspects, when a UE receives from a BS a desired power level for a subsequent uplink message transmission via a TPC field (indicating a TPC command value) in a RAR message, the UE implements a first technique to increase its transmission power to the extent possible based on the desired power level. For example, when a transmit power used for transmitting a RACH preamble (i.e., RACH transmission power) is P _rach-dB and a desired power boost (as indicated by the BS) is P _boost-dB, then desired uplink message transmission power is P _{msg3-desired-dB}=P _rach-dB+P _boost-dB, and an actual transmission power is P _{msg3-actual-dB} = min (P _max-dB, P _{msg3-desired-dB}) where P _max is a maximum transmission power of the UE (i.e., a transmit power constraint of the UE) as determined by a power class of the UE. After increasing the transmission power to the extent possible, the UE then computes a transmit power shortfall (i.e., a difference between the transmit power constraint of the UE and the desired power level) P _{msg3-shortfall-dB}= P _{msg3-desired-dB} –P _{msg3-actual-dB}. When P _{msg3-shortfall-dB}=0, then set numRep _msg3=1 (i.e., the uplink message is transmitted without any repetitions) . When P _{msg3-shortfall-dB}>0 set numRep _msg3 =min (2 ^x, maxRep _msg3) where

(i.e., for every 3 dB of transmit power shortfall, a number of repetitions of the uplink message are doubled unless exceeding a maximum number of repetitions allowed for the uplink message) . The UE then sends the uplink message to the BS at a power level of P _{msg3-actual-dB} and repeat it numRep _msg3 times.

In certain aspects, a BS may preconfigure a specific set of rules to determine a transmission power level adjustment and a number of repetitions of an uplink message instead of using a first technique (as noted above) to determine an appropriate number of repetitions of an uplink message. When the UE uses the first technique to determine the appropriate number of repetitions of the uplink message, the BS may not be aware of the number of repetitions of the uplink message the BS may receive. Accordingly, the BS may provision resources for a worst case number of repetitions of the uplink message that may result based on the transmission power level adjustment requested by the BS for the uplink message.

As illustrated in FIG. 10C, after determining a desired power level for reception of a subsequent uplink message, at 1005, a BS temporarily reserves a certain number of resources to accommodate possible uplink message repetitions based on the desired power level. In one example (as illustrated in FIG. 18) , if the BS requests a transmission power adjustment/boost of 6dB, the BS then plans for up to 4 possible repetitions of the uplink message from the UE in case UE is not able to adjust/boost its transmission power any further beyond the transmission power used for a RACH transmission (e.g., P _RACH = 23 dBm) . However, when the UE is able to adjust/boost its transmission power by 6 dB, the UE then determines that no repetitions of the uplink message are necessary. If the BS is unaware of this determination by the UE, it may still provision 4 resources for 4 possible repetitions of the uplink message.

Referring back to FIG. 10C, at 1010a, the UE sends a first transmission of the uplink message (msg3) and an indication of a number of times the UE will repeat the uplink message (e.g., 2 times as illustrated in FIG. 18) . For example, the UE sends the indication as an uplink control information (UCI) multiplexed with the uplink message.

Referring back to FIG. 10C, at 1011, the BS receives the first transmission of the uplink message, and decodes a UCI payload that is multiplexed with the uplink message. The BS then determines the number of times (e.g., 2 times) the UE intends to repeat the uplink message. The BS then reserves an appropriate number of resources (e.g., 2 resources) to accommodate the repetitions of the uplink message (based on an actual number of repetitions of the uplink message indicated by the UE) and repurpose any additional resources previously provisioned for the uplink message repetitions for other purposes (e.g., the BS frees up last two resources as illustrated in FIG. 18) .

In certain aspects, a UE sends information associated with a transmit power used for transmitting a RACH preamble to a BS. This information may be provided to the BS along with RACH preamble. In one example, a pool of RACH preamble sequences may be partitioned into multiple sets and depending on a power headroom available to the UE corresponding to a certain transmission power for the RACH preamble, the UE may select a set of the RACH preamble sequences from which a RACH preamble is selected. In another example, RACH transmission occasions may be designated for use based on the power headroom at the UE. On receiving this information, the BS may enable availability of additional power at the UE and accordingly determine appropriate transmission power level adjustment and number of repetitions of an uplink message.

In certain aspects, a UE receives from a BS an indication that the BS supports scheduling of repeated uplink message via a RAR TPC command. The UE interprets the RAR TPC command value based on the indication. In one example, the BS indicates to the UE via a SIB that the BS supports implicit scheduling of repeated initial transmission of a msg3 PUSCH (so that when a (Rel-17) UE accesses into a (Rel-15/16) network, the UE does not incorrectly interpret a TPC command in a RAR message as a multi-slot scheduling) .

In certain aspects, a UE sends to a BS an indication that the UE supports multi-slot transmission of an uplink message. The indication is provided to the BS via a RACH preamble format, a RACH preamble sequence, and/or a RACH transmission occasion. In one example, the UE sends this indication of a capability of the multi-slot transmission of a msg3 PUSCH via a msg1 (so that when a (Rel-15/16 legacy) UE accesses into a (Rel-17) network, the BS does not have to assume there might be a multi-slot initial transmission of the msg3 and thus needs to perform associated blind detection) by a dedicated RACH occasion and/or a dedicated preamble format (e.g., a long preamble with certain sequences) .

Aspects of the present disclosure make use of the relationship between a repetition of an uplink message transmission and a transmission power level adjustment to a transmit power used for transmitting a random access channel (RACH) preamble (e.g., msg1) . For example, increasing a number of repetitions of the uplink message transmission (such as doubling a number of repetitions of the uplink message transmission) may be equivalent to increasing the transmit power used for transmitting a RACH preamble (such as by 3 dB) .

In one non-limiting example, a UE (e.g., having a transmit power constraint of 23 dBm) may transmit a RACH preamble to a BS at a transmit power level (e.g., of 20 dBm) . The BS then indicates the UE to transmit a subsequent uplink message at a power level (e.g., 6 dB higher than its RACH transmit power (i.e., actual power of 26 dBm) ) . However, the UE can only adjusts it’s transmit power by 3 dB to transmit the subsequent uplink message before reaching the transmit power constraint. In such a case, even though the BS desired a power adjustment of 6 dB, the UE is only able to provide a 3 dB power adjustment, and will then send repetitions of the uplink message to the BS.

Example Wireless Communication Devices

FIG. 19 depicts an example communications device 1900 that includes various components operable, configured, or adapted to perform operations for the techniques disclosed herein, such as the operations depicted and described with respect to FIG. 9. In some examples, communication device 1900 may be a base station (BS) 102 as described, for example with respect to FIGS. 1 and 2.

Communications device 1900 includes a processing system 1902 coupled to a transceiver 1908 (e.g., a transmitter and/or a receiver) . Transceiver 1908 is configured to transmit (or send) and receive signals for the communications device 1900 via an antenna 1910, such as the various signals as described herein. Processing system 1902 may be configured to perform processing functions for communications device 1900, including processing signals received and/or to be transmitted by communications device 1900.

Processing system 1902 includes one or more processors 1920 coupled to a computer-readable medium/memory 1920 via a bus 1906. In certain aspects, computer-readable medium/memory 1920 is configured to store instructions (e.g., computer-executable code) that when executed by the one or more processors 1920, cause the one or more processors 1920 to perform the operations illustrated in FIG. 9, or other operations for performing the various techniques discussed herein.

In the depicted example, computer-readable medium/memory 1930 stores code 1931 for receiving from a user equipment (UE) a random access channel (RACH) preamble, code 1932 for sending to the UE a random access response (RAR) message indicating a transmit power control (TPC) command value and a rule, and code 1933 for monitoring for an uplink message from the UE sent in response to the RAR message with a number of a number repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.

In the depicted example, the one or more processors 1920 include circuitry configured to implement the code stored in the computer-readable medium/memory 1920, including circuitry 1921 for receiving from a UE a RACH preamble, circuitry 1922 for sending, to the UE a RAR message indicating a TPC command value and a rule, and circuitry 1923 for monitoring for an uplink message from the UE sent in response to the RAR message with a number of a number repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.

Various components of communications device 1900 may provide means for performing the methods described herein, including with respect to FIG. 9.

In some examples, means for transmitting or sending (or means for outputting for transmission) may include the transceivers 232 and/or antenna (s) 234 of the BS 102 illustrated in FIG. 2 and/or transceiver 1908 and antenna 1910 of the communication device 1900 in FIG. 19.

In some examples, means for receiving (or means for obtaining) may include the transceivers 232 and/or antenna (s) 234 of the BS 102 illustrated in FIG. 2 and/or transceiver 1908 and antenna 1910 of the communication device 1900 in FIG. 19.

In some examples, means for receiving from a UE a RACH preamble, means for sending to the UE a RAR message indicating a TPC command value and a rule, and means for monitoring for an uplink message from the UE sent in response to the RAR message with a number of a number repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule may include various processing system components, such as: the one or more processors 1920 in FIG. 19, or aspects of the BS 102 depicted in FIG. 2, including receive processor 238, transmit processor 220, TX MIMO processor 230, and/or controller/processor 240 (including msg3 component 241) .

Notably, FIG. 19 is just use example, and many other examples and configurations of communication device 1900 are possible.

FIG. 20 depicts an example communications device 2000 that includes various components operable, configured, or adapted to perform operations for the techniques disclosed herein, such as the operations depicted and described with respect to FIG. 12. In some examples, communication device 2000 may be a UE 104 as described, for example with respect to FIGS. 1 and 2.

Communications device 2000 includes a processing system 2002 coupled to a transceiver 2008 (e.g., a transmitter and/or a receiver) . Transceiver 2008 is configured to transmit (or send) and receive signals for the communications device 2000 via an antenna 2010, such as the various signals as described herein. Processing system 2002 may be configured to perform processing functions for communications device 2000, including processing signals received and/or to be transmitted by communications device 2000.

Processing system 2002 includes one or more processors 2020 coupled to a computer-readable medium/memory 2020 via a bus 2006. In certain aspects, computer-readable medium/memory 2020 is configured to store instructions (e.g., computer-executable code) that when executed by the one or more processors 2020, cause the one or more processors 2020 to perform the operations illustrated in FIG. 8, or other operations for performing the various techniques discussed herein.

In the depicted example, computer-readable medium/memory 2030 stores code 2031 for sending to a network entity a RACH preamble, code 2032 for receiving from the network entity a RAR message indicating a TPC command value and a rule, and code 2033 for sending an uplink message to the network entity in response to the RAR message where the uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.

In the depicted example, the one or more processors 2020 include circuitry configured to implement the code stored in the computer-readable medium/memory 2020, including circuitry 2021 or sending to a network entity a RACH preamble, circuitry 2022 for receiving from the network entity a RAR message indicating a TPC command value and a rule, and circuitry 2023 for sending an uplink message to the network entity in response to the RAR message where the uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.

Various components of communications device 2000 may provide means for performing the methods described herein, including with respect to FIG. 8.

In some examples, means for transmitting or sending (or means for outputting for transmission) may include the transceivers 254 and/or antenna (s) 252 of the UE 104 illustrated in FIG. 2 and/or transceiver 2008 and antenna 2010 of the communication device 2000 in FIG. 20.

In some examples, means for receiving (or means for obtaining) may include the transceivers 254 and/or antenna (s) 252 of the UE 104 illustrated in FIG. 2 and/or transceiver 2008 and antenna 2010 of the communication device 2000 in FIG. 20.

In some examples, means for sending to a network entity a RACH preamble, means for receiving from the network entity a RAR message indicating a TPC command value and a rule, and means for sending an uplink message to the network entity in response to the RAR message where the uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule may include various processing system components, such as: the one or more processors 2020 in FIG. 20, or aspects of the user equipment 104 depicted in FIG. 2, including receive processor 258, transmit processor 264, TX MIMO processor 266, and/or controller/processor 280 (including msg3 component 281) .

Notably, FIG. 20 is just use example, and many other examples and configurations of communication device 2000 are possible.

Example Clauses

Implementation examples are described in the following numbered clauses:

Clause 1: A method for wireless communications by a user equipment (UE) , comprising: sending, to a network entity, a random access channel (RACH) preamble; receiving, from the network entity, a random access response (RAR) message indicating a transmit power control (TPC) command value and a rule; and sending an uplink message to the network entity in response to the RAR message, wherein the uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.

Clause 2: The method alone or in combination with the first clause, wherein the number of repetitions of the uplink message is based on a difference between (i) a transmission power level adjusted by applying a power adjustment indicated by the TPC command value, relative to a transmit power used for transmitting the RACH preamble, and (ii) the transmit power constraint of the UE.

Clause 3: The method alone or in combination with one or more of the first and second clauses, wherein the number of repetitions is zero if the transmission power level adjusted based on a power adjustment indicated by the TPC command value is less than or equal to the transmit power constraint of the UE.

Clause 4: The method alone or in combination with one or more of the first through third clauses, further comprising determining the power adjustment indicated by the TPC command value based on a first mapping between TPC command values and power adjustment values that is different than a second mapping between TPC command values and power adjustment values used for other uplink transmissions.

Clause 5: The method alone or in combination with one or more of the first through fourth clauses, wherein the RAR includes a bit that indicates the UE is to determine the power adjustment indicated by the TPC command value based on the first mapping.

Clause 6: The method alone or in combination with one or more of the first through fifth clauses, further comprising providing, to the network entity, an indication of the number of repetitions.

Clause 7: The method alone or in combination with one or more of the first through sixth clauses, wherein the indication of the number of repetitions is provided as uplink control information (UCI) multiplexed with the uplink message.

Clause 8: The method alone or in combination with one or more of the first through seventh clauses, further comprising providing, to the network entity, an indication of a power headroom at the UE, the power headroom indicating a difference between the transmit power constraint of the UE and a transmit power used for transmitting the RACH preamble.

Clause 9: The method alone or in combination with one or more of the first through eighth clauses, wherein the indication of the power headroom is provided via selection of at least one of a RACH preamble sequence or a RACH transmission occasion.

Clause 10: The method alone or in combination with one or more of the first through ninth clauses, further comprising receiving, from the network entity, an indication of a maximum value for the number of repetitions.

Clause 11: The method alone or in combination with one or more of the first through tenth clauses, wherein the indication of the maximum value for the number of repetitions is provided via at least one of the RAR message or a system information block (SIB) .

Clause 12: The method alone or in combination with one or more of the first through eleventh clauses, further comprising receiving, from the network entity, an early termination indication; and terminating sending the uplink message early, prior to sending all of the repetitions in response to receiving the early termination indication.

Clause 13: The method alone or in combination with one or more of the first through twelfth clauses, wherein the early termination indication is provided via a downlink control information (DCI) .

Clause 14: The method alone or in combination with one or more of the first through thirteenth clauses, wherein the DCI schedules a subsequent downlink message or a retransmission of the uplink message.

Clause 15: The method alone or in combination with one or more of the first through fourteenth clauses, wherein the UE refrains from sending repetitions of the uplink message that occur a threshold amount of time after receiving the DCI.

Clause 16: The method alone or in combination with one or more of the first through fifteenth clauses, wherein the threshold amount of time is determined based on a subcarrier spacing (SCS) .

Clause 17: The method alone or in combination with one or more of the first through sixteenth clauses, wherein the UE sends the uplink message with repetition in non-consecutive slots.

Clause 18: The method alone or in combination with one or more of the first through seventeenth clauses, further comprising: receiving, from the network entity, an indication that the network entity supports scheduling of repeated uplink message via the RAR TPC command; and interpreting the RAR TPC command value based on the indication.

Clause 19: The method alone or in combination with one or more of the first through eighteenth clauses, further comprising: providing, to the network entity, an indication that the UE supports multi-slot transmission of the uplink message.

Clause 20: The method alone or in combination with one or more of the first through nineteenth clauses, wherein the indication that the UE supports multi-slot transmission of the uplink message is provided via a selection of at least one of a RACH preamble format, RACH preamble sequence, or a RACH transmission occasion.

Clause 21: A method for wireless communications by a network entity, comprising: receiving, from a user equipment (UE) , a random access channel (RACH) preamble; sending, to the UE, a random access response (RAR) message indicating a transmit power control (TPC) command value and a rule; and monitoring for an uplink message from the UE sent, in response to the RAR message, with a number of a number repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.

Clause 22: The method alone or in combination with the twenty-first clause, wherein the number of repetitions of the uplink message is based on a difference between (i) a transmission power level adjusted by applying a power adjustment indicated by the TPC command value, relative to a transmit power used for transmitting the RACH preamble, and (ii) the transmit power constraint of the UE.

Clause 23: The method alone or in combination with one or more of the twenty-first and twenty-second clauses, wherein the number of repetitions is zero if the transmission power level adjusted based on a power adjustment indicated by the TPC command value is less than or equal to the transmit power constraint of the UE.

Clause 24: The method alone or in combination with one or more of the twenty-first through twenty-third clauses, wherein the power adjustment indicated by the TPC command value is based on a first mapping between TPC command values and power adjustment values that is different than a second mapping between TPC command values and power adjustment values used for other uplink transmissions, and wherein the RAR includes a bit that indicates the UE is to determine the power adjustment indicated by the TPC command value based on the first mapping.

Clause 25: The method alone or in combination with one or more of the twenty-first through twenty-fourth clauses, further comprising receiving, from the UE, an indication of the number of repetitions, and wherein the indication of the number of repetitions is provided as uplink control information (UCI) multiplexed with the uplink message.

Clause 26: The method alone or in combination with one or more of the twenty-first through twenty-fifth clauses, further comprising receiving, from the UE, an indication of a power headroom at the UE, the power headroom indicating a difference between the transmit power constraint of the UE and a transmit power used for transmitting the RACH preamble, and wherein the indication of the power headroom is provided via a selection of at least one of a RACH preamble sequence or a RACH transmission occasion.

Clause 27: An apparatus, comprising: a memory comprising executable instructions; one or more processors configured to execute the executable instructions and cause the apparatus to perform a method in accordance with any one of Clauses 1-26.

Clause 28: An apparatus, comprising means for performing a method in accordance with any one of Clauses 1-26.

Clause 29: A non-transitory computer-readable medium comprising executable instructions that, when executed by one or more processors of an apparatus, cause the apparatus to perform a method in accordance with any one of Clauses 1-26.

Clause 30: A computer program product embodied on a computer-readable storage medium comprising code for performing a method in accordance with any one of Clauses 1-26.

Additional Wireless Communication Network Considerations

The techniques and methods described herein may be used for various wireless communications networks (or wireless wide area network (WWAN) ) and radio access technologies (RATs) . While aspects may be described herein using terminology commonly associated with 3G, 4G, and/or 5G (e.g., 5G new radio (NR) ) wireless technologies, aspects of the present disclosure may likewise be applicable to other communication systems and standards not explicitly mentioned herein.

5G wireless communication networks may support various advanced wireless communication services, such as enhanced mobile broadband (eMBB) , millimeter wave (mmWave) , machine type communications (MTC) , and/or mission critical targeting ultra-reliable, low-latency communications (URLLC) . These services, and others, may include latency and reliability requirements.

Returning to FIG. 1, various aspects of the present disclosure may be performed within the example wireless communication network 100.

In 3GPP, the term “cell” can refer to a coverage area of a NodeB and/or a narrowband subsystem serving this coverage area, depending on the context in which the term is used. In NR systems, the term “cell” and base station (BS) 102, next generation NodeB (gNB or gNodeB) , access point (AP) , distributed unit (DU) , carrier, or transmission reception point may be used interchangeably. A BS 102 may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or other types of cells.

A macro cell may generally cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by user equipments (UEs) 104 with service subscription. A pico cell may cover a relatively small geographic area (e.g., a sports stadium) and may allow unrestricted access by UEs 104 with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs 104 having an association with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG) and UEs 104 for users in the home) . A BS 102 for a macro cell may be referred to as a macro BS. A BS 102 for a pico cell may be referred to as a pico BS. A BS 102 for a femto cell may be referred to as a femto BS, home BS, or a home NodeB.

BSs 102 configured for 4G LTE (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN) ) may interface with the EPC 160 through first backhaul links 132 (e.g., an S1 interface) . BSs 102 configured for 5G (e.g., 5G NR or Next Generation RAN (NG-RAN) ) may interface with 5GC 190 through second backhaul links 184. BSs 102 may communicate directly or indirectly (e.g., through the EPC 160 or 5GC 190) with each other over third backhaul links 134 (e.g., X2 interface) . Third backhaul links 134 may generally be wired or wireless.

Small cell 102’ may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell 102’ may employ NR and use the same 5 GHz unlicensed frequency spectrum as used by the Wi-Fi AP 150. Small cell 102’ , employing NR in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network.

Some BSs 102, such as gNB 180 may operate in a traditional sub-6 GHz spectrum, in millimeter wave (mmWave) frequencies, and/or near mmWave frequencies in communication with the UE 104. When the gNB 180 operates in mmWave or near mmWave frequencies, the gNB 180 may be referred to as an mmWave base station.

The communication links 120 between BSs 102 and, for example, UEs 104, may be through one or more carriers. For example, BSs 102 and UEs 104 may use spectrum up to Y MHz (e.g., 5, 10, 15, 20, 100, 400, and other MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers) used for transmission in each direction. The carriers may or may not be adjacent to each other. Allocation of carriers may be asymmetric with respect to downlink (DL) and uplink (UL) (e.g., more or fewer carriers may be allocated for DL than for UL) . The component carriers may include a primary component carrier and one or more secondary component carriers. A primary component carrier may be referred to as a primary cell (PCell) and a secondary component carrier may be referred to as a secondary cell (SCell) .

Wireless communications system 100 further includes a Wi-Fi access point (AP) 150 in communication with Wi-Fi stations (STAs) 152 via communication links 154 in, for example, a 2.4 GHz and/or 5 GHz unlicensed frequency spectrum. When communicating in an unlicensed frequency spectrum, the STAs 152 /AP 150 may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

Certain UEs 104 may communicate with each other using device-to-device (D2D) communication link 158. The D2D communication link 158 may use the DL/UL WWAN spectrum. The D2D communication link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH) , a physical sidelink discovery channel (PSDCH) , a physical sidelink shared channel (PSSCH) , and a physical sidelink control channel (PSCCH) . D2D communication may be through a variety of wireless D2D communications systems, such as for example, FlashLinQ, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the IEEE 802.11 standard, 4G (e.g., LTE) , or 5G (e.g., NR) , to name a few options.

EPC 160 may include a Mobility Management Entity (MME) 162, other MMEs 164, a Serving Gateway 166, a Multimedia Broadcast Multicast Service (MBMS) Gateway 168, a Broadcast Multicast Service Center (BM-SC) 170, and a Packet Data Network (PDN) Gateway 172. MME 162 may be in communication with a Home Subscriber Server (HSS) 174. MME 162 is the control node that processes the signaling between the UEs 104 and the EPC 160. Generally, MME 162 provides bearer and connection management.

Generally, user Internet protocol (IP) packets are transferred through Serving Gateway 166, which itself is connected to PDN Gateway 172. PDN Gateway 172 provides UE IP address allocation as well as other functions. PDN Gateway 172 and the BM-SC 170 are connected to the IP Services 176, which may include, for example, the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a PS Streaming Service, and/or other IP services.

BM-SC 170 may provide functions for MBMS user service provisioning and delivery. BM-SC 170 may serve as an entry point for content provider MBMS transmission, may be used to authorize and initiate MBMS Bearer Services within a public land mobile network (PLMN) , and may be used to schedule MBMS transmissions. MBMS Gateway 168 may be used to distribute MBMS traffic to the base stations 102 belonging to a Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a particular service, and may be responsible for session management (start/stop) and for collecting eMBMS related charging information.

5GC 190 may include an Access and Mobility Management Function (AMF) 192, other AMFs 193, a Session Management Function (SMF) 194, and a User Plane Function (UPF) 195. AMF 192 may be in communication with a Unified Data Management (UDM) 196.

AMF 192 is generally the control node that processes the signaling between UEs 104 and 5GC 190. Generally, AMF 192 provides QoS flow and session management.

All user Internet protocol (IP) packets are transferred through UPF 195, which is connected to the IP Services 197, and which provides UE IP address allocation as well as other functions for 5GC 190. IP Services 197 may include, for example, the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a PS Streaming Service, and/or other IP services.

Returning to FIG. 2, various example components of BS 102 and UE 104 (e.g., the wireless communication network 100 of FIG. 1) are depicted, which may be used to implement aspects of the present disclosure.

At BS 102, a transmit processor 220 may receive data from a data source 212 and control information from a controller/processor 240. The control information may be for the physical broadcast channel (PBCH) , physical control format indicator channel (PCFICH) , physical hybrid ARQ indicator channel (PHICH) , physical downlink control channel (PDCCH) , group common PDCCH (GC PDCCH) , and others. The data may be for the physical downlink shared channel (PDSCH) , in some examples.

A medium access control (MAC) -control element (MAC-CE) is a MAC layer communication structure that may be used for control command exchange between wireless nodes. The MAC-CE may be carried in a shared channel such as a physical downlink shared channel (PDSCH) , a physical uplink shared channel (PUSCH) , or a physical sidelink shared channel (PSSCH) .

Processor 220 may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. Transmit processor 220 may also generate reference symbols, such as for the primary synchronization signal (PSS) , secondary synchronization signal (SSS) , PBCH demodulation reference signal (DMRS) , and channel state information reference signal (CSI-RS) .

Transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and/or the reference symbols, if applicable, and may provide output symbol streams to the modulators (MODs) in transceivers 232a-232t. Each modulator in transceivers 232a-232t may process a respective output symbol stream (e.g., for OFDM) to obtain an output sample stream. Each modulator may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. Downlink signals from the modulators in transceivers 232a-232t may be transmitted via the antennas 234a-234t, respectively.

At UE 104, antennas 252a-252r may receive the downlink signals from the BS 102 and may provide received signals to the demodulators (DEMODs) in transceivers 254a-254r, respectively. Each demodulator in transceivers 254a-254r may condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each demodulator may further process the input samples (e.g., for OFDM) to obtain received symbols.

MIMO detector 256 may obtain received symbols from all the demodulators in transceivers 254a-254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. Receive processor 258 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for the UE 104 to a data sink 260, and provide decoded control information to a controller/processor 280.

On the uplink, at UE 104, transmit processor 264 may receive and process data (e.g., for the physical uplink shared channel (PUSCH) ) from a data source 262 and control information (e.g., for the physical uplink control channel (PUCCH) from the controller/processor 280. Transmit processor 264 may also generate reference symbols for a reference signal (e.g., for the sounding reference signal (SRS) ) . The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by the modulators in transceivers 254a-254r (e.g., for SC-FDM) , and transmitted to BS 102.

At BS 102, the uplink signals from UE 104 may be received by antennas 234a-t, processed by the demodulators in transceivers 232a-232t, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 104. Receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to the controller/processor 240.

Memories

242 and 282 may store data and program codes for BS 102 and UE 104, respectively.

Scheduler 244 may schedule UEs for data transmission on the downlink and/or uplink.

5G may utilize orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) on the uplink and downlink. 5G may also support half-duplex operation using time division duplexing (TDD) . OFDM and single-carrier frequency division multiplexing (SC-FDM) partition the system bandwidth into multiple orthogonal subcarriers, which are also commonly referred to as tones and bins. Each subcarrier may be modulated with data. Modulation symbols may be sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing between adjacent subcarriers may be fixed, and the total number of subcarriers may be dependent on the system bandwidth. The minimum resource allocation, called a resource block (RB) , may be 12 consecutive subcarriers in some examples. The system bandwidth may also be partitioned into subbands. For example, a subband may cover multiple RBs. NR may support a base subcarrier spacing (SCS) of 15 KHz and other SCS may be defined with respect to the base SCS (e.g., 30 kHz, 60 kHz, 120 kHz, 240 kHz, and others) .

As above, FIGS. 3A-3D depict various example aspects of data structures for a wireless communication network, such as wireless communication network 100 of FIG. 1.

In various aspects, the 5G frame structure may be frequency division duplex (FDD) , in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for either DL or UL. 5G frame structures may also be time division duplex (TDD) , in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for both DL and UL. In the examples provided by FIGS. 3A and 3C, the 5G frame structure is assumed to be TDD, with subframe 4 being configured with slot format 28 (with mostly DL) , where D is DL, U is UL, and X is flexible for use between DL/UL, and subframe 3 being configured with slot format 34 (with mostly UL) . While

subframes

3, 4 are shown with slot formats 34, 28, respectively, any particular subframe may be configured with any of the various available slot formats 0-61. Slot formats 0, 1 are all DL, UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. UEs are configured with the slot format (dynamically through DL control information (DCI) , or semi-statically/statically through radio resource control (RRC) signaling) through a received slot format indicator (SFI) . Note that the description below applies also to a 5G frame structure that is TDD.

Other wireless communication technologies may have a different frame structure and/or different channels. A frame (10 ms) may be divided into 10 equally sized subframes (1 ms) . Each subframe may include one or more time slots. Subframes may also include mini-slots, which may include 7, 4, or 2 symbols. In some examples, each slot may include 7 or 14 symbols, depending on the slot configuration.

For example, for slot configuration 0, each slot may include 14 symbols, and for slot configuration 1, each slot may include 7 symbols. The symbols on DL may be cyclic prefix (CP) OFDM (CP-OFDM) symbols. The symbols on UL may be CP-OFDM symbols (for high throughput scenarios) or discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbols (also referred to as single carrier frequency-division multiple access (SC-FDMA) symbols) (for power limited scenarios; limited to a single stream transmission) .

The number of slots within a subframe is based on the slot configuration and the numerology. For slot configuration 0, different numerologies (μ) 0 to 5 allow for 1, 2, 4, 8, 16, and 32 slots, respectively, per subframe. For slot configuration 1, different numerologies 0 to 2 allow for 2, 4, and 8 slots, respectively, per subframe. Accordingly, for slot configuration 0 and numerology μ, there are 14 symbols/slot and 2μslots/subframe. The subcarrier spacing and symbol length/duration are a function of the numerology. The subcarrier spacing may be equal to 2 ^μ×15 kHz, where μ is the numerology 0 to 5. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=5 has a subcarrier spacing of 480 kHz. The symbol length/duration is inversely related to the subcarrier spacing. FIGS. 3A-3D provide an example of slot configuration 0 with 14 symbols per slot and numerology μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs.

A resource grid may be used to represent the frame structure. Each time slot includes a resource block (RB) (also referred to as physical RBs (PRBs) ) that extends 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs) . The number of bits carried by each RE depends on the modulation scheme.

As illustrated in FIG. 3A, some of the REs carry reference (pilot) signals (RS) for a UE (e.g., UE 104 of FIGS. 1 and 2) . The RS may include demodulation RS (DM-RS) (indicated as Rx for one particular configuration, where 100x is the port number, but other DM-RS configurations are possible) and channel state information reference signals (CSI-RS) for channel estimation at the UE. The RS may also include beam measurement RS (BRS) , beam refinement RS (BRRS) , and phase tracking RS (PT-RS) .

FIG. 3B illustrates an example of various DL channels within a subframe of a frame. The physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) , each CCE including nine RE groups (REGs) , each REG including four consecutive REs in an OFDM symbol.

A primary synchronization signal (PSS) may be within symbol 2 of particular subframes of a frame. The PSS is used by a UE (e.g., 104 of FIGS. 1 and 2) to determine subframe/symbol timing and a physical layer identity.

A secondary synchronization signal (SSS) may be within symbol 4 of particular subframes of a frame. The SSS is used by a UE to determine a physical layer cell identity group number and radio frame timing.

Based on the physical layer identity and the physical layer cell identity group number, the UE can determine a physical cell identifier (PCI) . Based on the PCI, the UE can determine the locations of the aforementioned DM-RS. The physical broadcast channel (PBCH) , which carries a master information block (MIB) , may be logically grouped with the PSS and SSS to form a synchronization signal (SS) /PBCH block. The MIB provides a number of RBs in the system bandwidth and a system frame number (SFN) . The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH such as system information blocks (SIBs) , and paging messages.

As illustrated in FIG. 3C, some of the REs carry DM-RS (indicated as R for one particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may transmit DM-RS for the physical uplink control channel (PUCCH) and DM-RS for the physical uplink shared channel (PUSCH) . The PUSCH DM-RS may be transmitted in the first one or two symbols of the PUSCH. The PUCCH DM-RS may be transmitted in different configurations depending on whether short or long PUCCHs are transmitted and depending on the particular PUCCH format used. The UE may transmit sounding reference signals (SRS) . The SRS may be transmitted in the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The SRS may be used by a base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

FIG. 3D illustrates an example of various UL channels within a subframe of a frame. The PUCCH may be located as indicated in one configuration. The PUCCH carries uplink control information (UCI) , such as scheduling requests, a channel quality indicator (CQI) , a precoding matrix indicator (PMI) , a rank indicator (RI) , and HARQ ACK/NACK feedback. The PUSCH carries data, and may additionally be used to carry a buffer status report (BSR) , a power headroom report (PHR) , and/or UCI.

Additional Considerations

The preceding description provides examples of techniques for repeated initial transmission of an uplink random access channel (RACH) message (e.g., msg3 message) in communication systems. The preceding description is provided to enable any person skilled in the art to practice the various aspects described herein. The examples discussed herein are not limiting of the scope, applicability, or aspects set forth in the claims. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. For example, changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For instance, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Also, features described with respect to some examples may be combined in some other examples. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method that is practiced using other structure, functionality, or structure and functionality in addition to, or other than, the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.

The techniques described herein may be used for various wireless communication technologies, such as 5G (e.g., 5G NR) , 3GPP Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , code division multiple access (CDMA) , time division multiple access (TDMA) , frequency division multiple access (FDMA) , orthogonal frequency division multiple access (OFDMA) , single-carrier frequency division multiple access (SC-FDMA) , time division synchronous code division multiple access (TD-SCDMA) , and other networks. The terms “network” and “system” are often used interchangeably. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA) , cdma2000, and others. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95 and IS-856 standards. A TDMA network may implement a radio technology such as Global System for Mobile Communications (GSM) . An OFDMA network may implement a radio technology such as NR (e.g. 5G RA) , Evolved UTRA (E-UTRA) , Ultra Mobile Broadband (UMB) , IEEE 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDMA, and others. UTRA and E-UTRA are part of Universal Mobile Telecommunication System (UMTS) . LTE and LTE-A are releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSM are described in documents from an organization named “3rd Generation Partnership Project” (3GPP) . cdma2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2) . NR is an emerging wireless communications technology under development.

The various illustrative logical blocks, modules and circuits described in connection with the present disclosure may be implemented or performed with a general purpose processor, a DSP, an ASIC, a field programmable gate array (FPGA) or other programmable logic device (PLD) , discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any commercially available processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, a system on a chip (SoC) , or any other such configuration.

If implemented in hardware, an example hardware configuration may comprise a processing system in a wireless node. The processing system may be implemented with a bus architecture. The bus may include any number of interconnecting buses and bridges depending on the specific application of the processing system and the overall design constraints. The bus may link together various circuits including a processor, machine-readable media, and a bus interface. The bus interface may be used to connect a network adapter, among other things, to the processing system via the bus. The network adapter may be used to implement the signal processing functions of the PHY layer. In the case of a user equipment (see FIG. 1) , a user interface (e.g., keypad, display, mouse, joystick, touchscreen, biometric sensor, proximity sensor, light emitting element, and others) may also be connected to the bus. The bus may also link various other circuits such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further. The processor may be implemented with one or more general-purpose and/or special-purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuitry that can execute software. Those skilled in the art will recognize how best to implement the described functionality for the processing system depending on the particular application and the overall design constraints imposed on the overall system.

If implemented in software, the functions may be stored or transmitted over as one or more instructions or code on a computer readable medium. Software shall be construed broadly to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Computer-readable media include both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. The processor may be responsible for managing the bus and general processing, including the execution of software modules stored on the machine-readable storage media. A computer-readable storage medium may be coupled to a processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. By way of example, the machine-readable media may include a transmission line, a carrier wave modulated by data, and/or a computer readable storage medium with instructions stored thereon separate from the wireless node, all of which may be accessed by the processor through the bus interface. Alternatively, or in addition, the machine-readable media, or any portion thereof, may be integrated into the processor, such as the case may be with cache and/or general register files. Examples of machine-readable storage media may include, by way of example, RAM (Random Access Memory) , flash memory, ROM (Read Only Memory) , PROM (Programmable Read-Only Memory) , EPROM (Erasable Programmable Read-Only Memory) , EEPROM (Electrically Erasable Programmable Read-Only Memory) , registers, magnetic disks, optical disks, hard drives, or any other suitable storage medium, or any combination thereof. The machine-readable media may be embodied in a computer-program product.

A software module may comprise a single instruction, or many instructions, and may be distributed over several different code segments, among different programs, and across multiple storage media. The computer-readable media may comprise a number of software modules. The software modules include instructions that, when executed by an apparatus such as a processor, cause the processing system to perform various functions. The software modules may include a transmission module and a receiving module. Each software module may reside in a single storage device or be distributed across multiple storage devices. By way of example, a software module may be loaded into RAM from a hard drive when a triggering event occurs. During execution of the software module, the processor may load some of the instructions into cache to increase access speed. One or more cache lines may then be loaded into a general register file for execution by the processor. When referring to the functionality of a software module below, it will be understood that such functionality is implemented by the processor when executing instructions from that software module.

As used herein, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .

As used herein, the term “determining” encompasses a wide variety of actions. For example, “determining” may include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure) , ascertaining and the like. Also, “determining” may include receiving (e.g., receiving information) , accessing (e.g., accessing data in a memory) and the like. Also, “determining” may include resolving, selecting, choosing, establishing and the like.

The methods disclosed herein comprise one or more steps or actions for achieving the methods. The method steps and/or actions may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims. Further, the various operations of methods described above may be performed by any suitable means capable of performing the corresponding functions. The means may include various hardware and/or software component (s) and/or module (s) , including, but not limited to a circuit, an application specific integrated circuit (ASIC) , or processor. Generally, where there are operations illustrated in figures, those operations may have corresponding counterpart means-plus-function components with similar numbering.

The following claims are not intended to be limited to the aspects shown herein, but are to be accorded the full scope consistent with the language of the claims. Within a claim, reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” Unless specifically stated otherwise, the term “some” refers to one or more. No claim element is to be construed under the provisions of 35 U.S.C. §112 (f) unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for. ” All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims.

Claims

A method for wireless communications by a user equipment (UE) , comprising:

sending, to a network entity, a random access channel (RACH) preamble;

receiving, from the network entity, a random access response (RAR) message indicating a transmit power control (TPC) command value and a rule; and

sending an uplink message to the network entity in response to the RAR message, wherein the uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.
The method of claim 1, wherein the number of repetitions of the uplink message is based on a difference between (i) a transmission power level adjusted by applying a power adjustment indicated by the TPC command value, relative to a transmit power used for transmitting the RACH preamble, and (ii) the transmit power constraint of the UE.
The method of claim 2, wherein the number of repetitions is zero if the transmission power level adjusted based on a power adjustment indicated by the TPC command value is less than or equal to the transmit power constraint of the UE.
The method of claim 2, further comprising determining the power adjustment indicated by the TPC command value based on a first mapping between TPC command values and power adjustment values that is different than a second mapping between TPC command values and power adjustment values used for other uplink transmissions.
The method of claim 4, wherein the RAR includes a bit that indicates the UE is to determine the power adjustment indicated by the TPC command value based on the first mapping.
The method of claim 1, further comprising providing, to the network entity, an indication of the number of repetitions.
The method of claim 6, wherein the indication of the number of repetitions is provided as uplink control information (UCI) multiplexed with the uplink message.
The method of claim 1, further comprising providing, to the network entity, an indication of a power headroom at the UE, the power headroom indicating a difference between the transmit power constraint of the UE and a transmit power used for transmitting the RACH preamble.
The method of claim 8, wherein the indication of the power headroom is provided via selection of at least one of a RACH preamble sequence or a RACH transmission occasion.
The method of claim 1, further comprising receiving, from the network entity, an indication of a maximum value for the number of repetitions.
The method of claim 10, wherein the indication of the maximum value for the number of repetitions is provided via at least one of the RAR message or a system information block (SIB) .
The method of claim 1, further comprising:

receiving, from the network entity, an early termination indication; and

terminating sending the uplink message early, prior to sending all of the repetitions in response to receiving the early termination indication.
The method of claim 12, wherein the early termination indication is provided via a downlink control information (DCI) .
The method of claim 13, wherein the DCI schedules a subsequent downlink message or a retransmission of the uplink message.
The method of claim 13, wherein the UE refrains from sending repetitions of the uplink message that occur a threshold amount of time after receiving the DCI.
The method of claim 15, wherein the threshold amount of time is determined based on a subcarrier spacing (SCS) .
The method of claim 1, wherein the UE sends the uplink message with repetition in non-consecutive slots.
The method of claim 1, further comprising:

receiving, from the network entity, an indication that the network entity supports scheduling of repeated uplink message via the RAR TPC command; and

interpreting the RAR TPC command value based on the indication.
The method of claim 1, further comprising:

providing, to the network entity, an indication that the UE supports multi-slot transmission of the uplink message.
The method of claim 19, wherein the indication that the UE supports multi-slot transmission of the uplink message is provided via a selection of at least one of a RACH preamble format, RACH preamble sequence, or a RACH transmission occasion.
A method for wireless communications by a network entity, comprising:

receiving, from a user equipment (UE) , a random access channel (RACH) preamble;

sending, to the UE, a random access response (RAR) message indicating a transmit power control (TPC) command value and a rule; and

monitoring for an uplink message from the UE sent, in response to the RAR message, with a number of a number repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.
The method of claim 21, wherein the number of repetitions of the uplink message is based on a difference between (i) a transmission power level adjusted by applying a power adjustment indicated by the TPC command value, relative to a transmit power used for transmitting the RACH preamble, and (ii) the transmit power constraint of the UE.
The method of claim 22, wherein the number of repetitions is zero if the transmission power level adjusted based on a power adjustment indicated by the TPC command value is less than or equal to the transmit power constraint of the UE.
The method of claim 22, wherein the power adjustment indicated by the TPC command value is based on a first mapping between TPC command values and power adjustment values that is different than a second mapping between TPC command values and power adjustment values used for other uplink transmissions, and wherein the RAR includes a bit that indicates the UE is to determine the power adjustment indicated by the TPC command value based on the first mapping.
The method of claim 21, further comprising receiving, from the UE, an indication of the number of repetitions, and wherein the indication of the number of repetitions is provided as uplink control information (UCI) multiplexed with the uplink message.
The method of claim 21, further comprising receiving, from the UE, an indication of a power headroom at the UE, the power headroom indicating a difference between the transmit power constraint of the UE and a transmit power used for transmitting the RACH preamble, and wherein the indication of the power headroom is provided via a selection of at least one of a RACH preamble sequence or a RACH transmission occasion.
An apparatus for wireless communications by a user equipment (UE) , comprising:

at least one processor and a memory configured to:

send, to a network entity, a random access channel (RACH) preamble;

receive, from the network entity, a random access response (RAR) message indicating a transmit power control (TPC) command value and a rule; and

send an uplink message to the network entity in response to the RAR message, wherein the uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.
The apparatus of claim 27, wherein the number of repetitions of the uplink message is based on a difference between (i) a transmission power level adjusted by applying a power adjustment indicated by the TPC command value, relative to a transmit power used for transmitting the RACH preamble, and (ii) the transmit power constraint of the UE, and wherein the number of repetitions is zero if the transmission power level adjusted based on a power adjustment indicated by the TPC command value is less than or equal to the transmit power constraint of the UE.
An apparatus for wireless communications by a user equipment (UE) , comprising:

sending, to a network entity, a random access channel (RACH) preamble;

receiving, from the network entity, a random access response (RAR) message indicating a transmit power control (TPC) command value and a rule; and

sending an uplink message to the network entity in response to the RAR message, wherein the uplink message is sent with a number of repetitions based on the TPC command value, a transmit power constraint of the UE, and the rule.
The apparatus of claim 29, wherein the number of repetitions of the uplink message is based on a difference between (i) a transmission power level adjusted by applying a power adjustment indicated by the TPC command value, relative to a transmit power used for transmitting the RACH preamble, and (ii) the transmit power constraint of the UE, and wherein the number of repetitions is zero if the transmission power level adjusted based on a power adjustment indicated by the TPC command value is less than or equal to the transmit power constraint of the UE.