Multiple prach transmissions with power variations

Abstract

The apparatus may be a wireless device such as a user equipment (UE) or component thereof configured to obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and transmit, to a network node, the plurality of random access message transmissions using the power variation pattern. The apparatus may be a network device such as a base station or component thereof configured to transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and receive, from a UE, the plurality of random access message transmissions using the power variation pattern.

Description

Qualcomm Ref. No. 2407699WO 1 / 79MULTIPLE PRACH TRANSMISSIONS WITH POWER VARIATIONSCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of Greek Patent Application No. 20240100891, entitled “MULTIPLE PRACH TRANSMISSIONS WITH POWER VARIATIONS” and filed on December 17, 2024, which is expressly incorporated by reference herein in its entirety.TECHNICAL FIELD

[0002] The present disclosure relates generally to communication systems, and more particularly, to a random access process for initial access.INTRODUCTION

[0003] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.

[0004] These 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. An example telecommunication standard is 5G New Radio (NR). 5G NR is part of a continuous mobile broadband evolution promulgated by Third Generation Partnership Project (3 GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with Internet of Things (IoT)), and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra-reliable low latency communications (URLLC). Some aspects of 5G NR may be based on the 4G Long129025-2544WO01Qualcomm Ref. No. 2407699WO 2 / 79Term Evolution (LTE) standard. There exists a need for further improvements in 5G NR technology. These improvements may also be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.BRIEF SUMMARY

[0005] The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects. This summary neither identifies key or critical elements of all aspects nor delineates the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

[0006] In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a wireless device such as a user equipment (UE) or component thereof configured to obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and transmit, to a network node, the plurality of random access message transmissions using the power variation pattern.

[0007] In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a network device such as a base station or component thereof configured to transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and receive, from a UE, the plurality of random access message transmissions using the power variation pattern.

[0008] To the accomplishment of the foregoing and related ends, the one or more aspects may include the features hereinafter fully described and particularly pointed out in the claims. The following description and the drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. l is a diagram illustrating an example of a wireless communications system and an access network.129025-2544WO01Qualcomm Ref. No. 2407699WO 3 / 79

[0010] FIG. 2A is a diagram illustrating an example of a first frame, in accordance with various aspects of the present disclosure.

[0011] FIG. 2B is a diagram illustrating an example of downlink (DL) channels within a subframe, in accordance with various aspects of the present disclosure.

[0012] FIG. 2C is a diagram illustrating an example of a second frame, in accordance with various aspects of the present disclosure.

[0013] FIG. 2D is a diagram illustrating an example of uplink (UL) channels within a subframe, in accordance with various aspects of the present disclosure.

[0014] FIG. 3 is a diagram illustrating an example of a base station and user equipment (UE) in an access network.

[0015] FIG. 4 illustrates example aspects of a random access procedure between a UE and a base station.

[0016] FIG. 5 is a call flow diagram illustrating example aspects of a collisions associated with a first random access procedure between a UE and a base station and a second random access procedure between a UE and the base station.

[0017] FIG. 6A is a diagram illustrating resources associated with ROs in accordance with some aspects of the disclosure.

[0018] FIG. 6B is a diagram illustrating a transmission of multiple first random access messages (or message transmissions) within a same RO using different preambles in accordance with some aspects of the disclosure.

[0019] FIG. 6C is a diagram illustrating a transmission of multiple first random access messages (or message transmissions) within different ROs using a same time resource and using different preambles in accordance with some aspects of the disclosure.

[0020] FIG. 6D is a diagram illustrating a transmission of multiple first random access messages (or message transmissions) within different ROs using a different time resource and using different preambles in accordance with some aspects of the disclosure.

[0021] FIG. 7 is a set of diagrams illustrating different power variation patterns and their association with first transmissions of a first random access message (Msg 1) in a set of multiple first random access message transmissions in accordance with some aspects of the disclosure.129025-2544WO01Qualcomm Ref. No. 2407699WO 4 / 79

[0022] FIG. 8A is a diagram illustrating a set of preambles and timing advance values associated with different first random access messages received during a first RO in accordance with some aspects of the disclosure.

[0023] FIG. 8B is a diagram illustrating a set of preambles and timing advance values associated with different first random access messages received during a first RO and a second RO in accordance with some aspects of the disclosure.

[0024] FIG. 8C is a set of diagrams illustrating different possibilities for indications of timing advances (TAs) and transmission power control (TPC) values that may be received by a UE in accordance with some aspects of the disclosure.

[0025] FIG. 9 is a call flow diagram illustrating a method of wireless communication in accordance with some aspects of the disclosure.

[0026] FIG. 10 is a flowchart of a method of wireless communication.

[0027] FIG. 11 is a flowchart of a method of wireless communication.

[0028] FIG. 12 is a flowchart of a method of wireless communication.

[0029] FIG. 13 is a flowchart of a method of wireless communication.

[0030] FIG. 14 is a diagram illustrating an example of a hardware implementation for an apparatus.

[0031] FIG. 15 is a diagram illustrating an example of a hardware implementation for a network entity.DETAILED DESCRIPTION

[0032] In some aspects of wireless communication, initial access procedures may be contention based and may suffer from collisions between initial access attempts associated with and / or transmitted by different users. For example, a physical random access channel (PRACH) collision may occur when two UEs choose a same PRACH resource (e.g., a same set of time-and-frequency resources associated with a same random access channel (RACH) occasion (RO) and using a same preamble sequence) to transmit a first random access message (e.g., which may be referred to as a msgl, a msg 1, a Msgl, or a Msg 1). Collisions between random access messages (e.g., “Msg l”s) transmitted by two or more UEs may introduce challenges in identifying and / or distinguishing the two or more transmitting UEs. In some aspects, a base station may consider the multiple colliding random access messages as being associated with a single UE, and send out a single random access response (RAR)129025-2544WO01Qualcomm Ref. No. 2407699WO 5 / 79 message (e.g., which may be referred to as a msg2, a msg 2, a Msg2, or a Msg 2) including a grant for a subsequent message (e.g., which may be referred to as a msg3, a msg 3, a Msg3, or a Msg 3) associated with the random access procedure.

[0033] The UEs receiving the RAR message, in some aspects, may treat the UL grant as being for the UE as the RAR UL grant will use the preamble sequence (or PRACH resource) transmitted as a temporary ID to distinguish UEs. Accordingly, a collision at the granted UL resources for transmission of the subsequent message (e.g., msg3, a msg 3, a Msg3, or a Msg 3) may occur and contention resolution will be performed to further distinguish between the UEs. In some aspects, this type of collision may be referred to as a sequence domain collision.

[0034] In some aspects using the multiple first random access transmissions based on the multiple randomly selected preamble sequences, the network and / or the base station may not be able to determine which PRACH transmissions across multiple ROs are from the same UE. Accordingly, the use of the multiple first random access transmissions based on the multiple randomly selected preamble sequences, in some aspects, may lead to the base station to allocate a higher number, or larger amount, of UL resources for third random access messages (e.g., “Msg 3”s), particularly, in the case of multiple successful (e.g., non-colliding) preamble sequences transmitted by a UE. For example, because the base station may not be capable of identifying related PRACH transmissions, the base station may allocate resources for a Msg 3 for each successful preamble from the UE, whereas the UE may use a single Msg 3 resource. Additionally, the performance of the use of the multiple first random access transmissions based on the multiple randomly selected preamble sequences, in some aspects, may depend on a collision detection capability of the base station and / or the UE.

[0035] Various aspects relate generally to using transmit power variations at a UE between the multiple transmitted preambles to improve the msg3 resource allocation and collision detection. Some aspects more specifically relate to adding a power-domain signature to multiple RACH / PRACH / Msg 1 transmissions (e.g., the multiple first random access transmissions based on the multiple randomly selected preamble sequences as discussed above). In some aspects, the use of the transmit power variations (e.g., an additional power-domain signature applied to multiple PRACH transmissions) may allow the base station to identify which detected preambles over129025-2544WO01Qualcomm Ref. No. 2407699WO 6 / 79 multiple ROs are associated with the same UE based on the power pattern and detected delays. The base station may allocate a single set of resources for a third random access message (e.g., a “Msg 3”) and send a single Msg 2 for the multiple first random access transmissions. From the UE’s perspective, if multiple “Msg 2”s are received, it can identify which “Msg 2”s correspond to its own PRACH transmissions based on the power variation pattern (i.e., TPC) and combine them to improve TA and TPC accuracy. In some examples, a UE may be configured to obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and transmit, to a network node, the plurality of random access message transmissions using the power variation pattern. In some aspects, a network device may be configured to transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and receive, from a UE, the plurality of random access message transmissions using the power variation pattern.

[0036] Particular aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. In some examples, by introducing transmit power variations at a UE between the multiple transmitted preambles, the described techniques can be used to improve resource allocation for Msg 3 and reduce collisions between random access messages transmitted by different UEs.

[0037] The detailed description set forth below in connection with the drawings describes various configurations and does not represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

[0038] Several aspects of telecommunication systems are presented with reference to various apparatus and methods. These apparatus and methods are described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements”). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are129025-2544WO01Qualcomm Ref. No. 2407699WO 7 / 79 implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

[0039] By way of example, an element, or any portion of an element, or any combination of elements may be implemented as a “processing system” that includes one or more processors. When multiple processors are implemented, the multiple processors may perform the functions individually or in combination. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, systems on a chip (SoC), baseband processors, field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software. Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise, shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, or any combination thereof.

[0040] Accordingly, in one or more example aspects, implementations, and / or use cases, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer. By way of example, such computer-readable media can include a random-access memory (RAM), a read-only memory (ROM), an electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the types of computer- readable media, or any other medium that can be used to store computer executable code in the form of instructions or data structures that can be accessed by a computer.

[0041] While aspects, implementations, and / or use cases are described in this application by illustration to some examples, additional or different aspects, implementations and / or use cases may come about in many different arrangements and scenarios. Aspects,129025-2544WO01Qualcomm Ref. No. 2407699WO 8 / 79 implementations, and / or use cases described herein may be implemented across many differing platform types, devices, systems, shapes, sizes, and packaging arrangements. For example, aspects, implementations, and / or use cases may come about via integrated chip implementations and other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail / purchasing devices, medical devices, artificial intelligence (Al)-enabled devices, etc.). While some examples may or may not be specifically directed to use cases or applications, a wide assortment of applicability of described examples may occur. Aspects, implementations, and / or use cases may range a spectrum from chip-level or modular components to non-modular, non-chip- level implementations and further to aggregate, distributed, or original equipment manufacturer (OEM) devices or systems incorporating one or more techniques herein. In some practical settings, devices incorporating described aspects and features may also include additional components and features for implementation and practice of claimed and described aspect. For example, transmission and reception of wireless signals necessarily includes a number of components for analog and digital purposes (e.g., hardware components including antenna, RF-chains, power amplifiers, modulators, buffer, processor(s), interleaver, adders / summers, etc.). Techniques described herein may be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, aggregated or disaggregated components, end-user devices, etc. of varying sizes, shapes, and constitution.

[0042] Deployment of communication systems, such as 5GNR systems, may be arranged in multiple manners with various components or constituent parts. In a 5G NR system, or network, a network node, a network entity, a mobility element of a network, a radio access network (RAN) node, a core network node, a network element, or a network equipment, such as a base station (BS), or one or more units (or one or more components) performing base station functionality, may be implemented in an aggregated or disaggregated architecture. For example, a BS (such as a Node B (NB), evolved NB (eNB), NR BS, 5G NB, access point (AP), a transmission reception point (TRP), or a cell, etc.) may be implemented as an aggregated base station (also known as a standalone BS or a monolithic BS) or a disaggregated base station.

[0043] An aggregated base station may be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node. A disaggregated base129025-2544WO01Qualcomm Ref. No. 2407699WO 9 / 79 station may be configured to utilize a protocol stack that is physically or logically distributed among two or more units (such as one or more central or centralized units (CUs), one or more distributed units (DUs), or one or more radio units (RUs)). In some aspects, a CU may be implemented within a RAN node, and one or more DUs may be co-located with the CU, or alternatively, may be geographically or virtually distributed throughout one or multiple other RAN nodes. The DUs may be implemented to communicate with one or more RUs. Each of the CU, DU and RU can be implemented as virtual units, i.e., a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU).

[0044] Base station operation or network design may consider aggregation characteristics of base station functionality. For example, disaggregated base stations may be utilized in an integrated access backhaul (IAB) network, an open radio access network (O- RAN (such as the network configuration sponsored by the O-RAN Alliance)), or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN)). Disaggregation may include distributing functionality across two or more units at various physical locations, as well as distributing functionality for at least one unit virtually, which can enable flexibility in network design. The various units of the disaggregated base station, or disaggregated RAN architecture, can be configured for wired or wireless communication with at least one other unit.

[0045] FIG. 1 is a diagram 100 illustrating an example of a wireless communications system and an access network. The illustrated wireless communications system includes a disaggregated base station architecture. The disaggregated base station architecture may include one or more CUs 110 that can communicate directly with a core network 120 via a backhaul link, or indirectly with the core network 120 through one or more disaggregated base station units (such as a Near-Real Time (Near-RT) RAN Intelligent Controller (RIC) 125 via an E2 link, or a Non-Real Time (Non-RT) RIC 115 associated with a Service Management and Orchestration (SMO) Framework 105, or both). A CU 110 may communicate with one or more DUs 130 via respective midhaul links, such as an Fl interface. The DUs 130 may communicate with one or more RUs 140 via respective fronthaul links. The RUs 140 may communicate with respective UEs 104 via one or more radio frequency (RF) access links. In some implementations, the UE 104 may be simultaneously served by multiple RUs 140.129025-2544WO01Qualcomm Ref. No. 2407699WO 10 / 79

[0046] Each of the units, i.e., the CUs 110, the DUs 130, the RUs 140, as well as the Near- RT RICs 125, the Non-RT RICs 115, and the SMO Framework 105, may include one or more interfaces or be coupled to one or more interfaces configured to receive or to transmit signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units, or an associated processor or controller providing instructions to the communication interfaces of the units, can be configured to communicate with one or more of the other units via the transmission medium. For example, the units can include a wired interface configured to receive or to transmit signals over a wired transmission medium to one or more of the other units. Additionally, the units can include a wireless interface, which may include a receiver, a transmitter, or a transceiver (such as an RF transceiver), configured to receive or to transmit signals, or both, over a wireless transmission medium to one or more of the other units.

[0047] In some aspects, the CU 110 may host one or more higher layer control functions. Such control functions can include radio resource control (RRC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), or the like. Each control function can be implemented with an interface configured to communicate signals with other control functions hosted by the CU 110. The CU 110 may be configured to handle user plane functionality (i.e., Central Unit - User Plane (CU-UP)), control plane functionality (i.e., Central Unit - Control Plane (CU-CP)), or a combination thereof. In some implementations, the CU 110 can be logically split into one or more CU-UP units and one or more CU-CP units. The CU-UP unit can communicate bidirectionally with the CU-CP unit via an interface, such as an El interface when implemented in an O-RAN configuration. The CU 110 can be implemented to communicate with the DU 130, as necessary, for network control and signaling.

[0048] The DU 130 may correspond to a logical unit that includes one or more base station functions to control the operation of one or more RUs 140. In some aspects, the DU 130 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation, demodulation, or the like) depending, at least in part, on a functional split, such as those defined by 3 GPP. In some aspects, the DU 130 may further host one or more129025-2544WO01Qualcomm Ref. No. 2407699WO 11 / 79 low PHY layers. Each layer (or module) can be implemented with an interface configured to communicate signals with other layers (and modules) hosted by the DU 130, or with the control functions hosted by the CU 110.

[0049] Lower-layer functionality can be implemented by one or more RUs 140. In some deployments, an RU 140, controlled by a DU 130, may correspond to a logical node that hosts RF processing functions, or low-PHY layer functions (such as performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, or the like), or both, based at least in part on the functional split, such as a lower layer functional split. In such an architecture, the RU(s) 140 can be implemented to handle over the air (OTA) communication with one or more UEs 104. In some implementations, real-time and non-real-time aspects of control and user plane communication with the RU(s) 140 can be controlled by the corresponding DU 130. In some scenarios, this configuration can enable the DU(s) 130 and the CU 110 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.

[0050] The SMO Framework 105 may be configured to support RAN deployment and provisioning of non-virtualized and virtualized network elements. For non-virtualized network elements, the SMO Framework 105 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements that may be managed via an operations and maintenance interface (such as an 01 interface). For virtualized network elements, the SMO Framework 105 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 190) to perform network element life cycle management (such as to instantiate virtualized network elements) via a cloud computing platform interface (such as an 02 interface). Such virtualized network elements can include, but are not limited to, CUs 110, DUs 130, RUs 140 and Near-RT RICs 125. In some implementations, the SMO Framework 105 can communicate with a hardware aspect of a 4G RAN, such as an open eNB (O- eNB) 111, via an 01 interface. Additionally, in some implementations, the SMO Framework 105 can communicate directly with one or more RUs 140 via an 01 interface. The SMO Framework 105 also may include a Non-RT RIC 115 configured to support functionality of the SMO Framework 105.

[0051] The Non-RT RIC 115 may be configured to include a logical function that enables non-real-time control and optimization of RAN elements and resources, artificial129025-2544WO01Qualcomm Ref. No. 2407699WO 12 / 79 intelligence (Al) / machine learning (ML) (AI / ML) workflows including model training and updates, or policy-based guidance of applications / features in the Near- RT RIC 125. The Non-RT RIC 115 may be coupled to or communicate with (such as via an Al interface) the Near-RT RIC 125. The Near-RT RIC 125 may be configured to include a logical function that enables near-real-time control and optimization of RAN elements and resources via data collection and actions over an interface (such as via an E2 interface) connecting one or more CUs 110, one or more DUs 130, or both, as well as an O-eNB, with the Near-RT RIC 125.

[0052] In some implementations, to generate AI / ML models to be deployed in the Near-RT RIC 125, the Non-RT RIC 115 may receive parameters or external enrichment information from external servers. Such information may be utilized by the Near-RT RIC 125 and may be received at the SMO Framework 105 or the Non-RT RIC 115 from non-network data sources or from network functions. In some examples, the Non-RT RIC 115 or the Near-RT RIC 125 may be configured to tune RAN behavior or performance. For example, the Non-RT RIC 115 may monitor long-term trends and patterns for performance and employ AI / ML models to perform corrective actions through the SMO Framework 105 (such as reconfiguration via 01) or via creation of RAN management policies (such as Al policies).

[0053] At least one of the CU 110, the DU 130, and the RU 140 may be referred to as a base station 102. Accordingly, a base station 102 may include one or more of the CU 110, the DU 130, and the RU 140 (each component indicated with dotted lines to signify that each component may or may not be included in the base station 102). The base station 102 provides an access point to the core network 120 for a UE 104. The base station 102 may include macrocells (high power cellular base station) and / or small cells (low power cellular base station). The small cells include femtocells, picocells, and microcells. A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include Home Evolved Node Bs (eNBs) (HeNBs), which may provide service to a restricted group known as a closed subscriber group (CSG). The communication links between the RUs 140 and the UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to an RU 140 and / or downlink (DL) (also referred to as forward link) transmissions from an RU 140 to a UE 104. The communication links may use multiple-input and multiple-output (MIMO) antenna technology, including129025-2544WO01Qualcomm Ref. No. 2407699WO 13 / 79 spatial multiplexing, beamforming, and / or transmit diversity. The communication links may be through one or more carriers. The base station 102 / UEs 104 may use spectrum up to F MHz (e.g., 5, 10, 15, 20, 100, 400, etc. MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Fx 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 DL and 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).

[0054] 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 wireless wide area network (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, Bluetooth™ (Bluetooth is a trademark of the Bluetooth Special Interest Group (SIG)), Wi-Fi™ (Wi-Fi is a trademark of the Wi-Fi Alli ance) based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.

[0055] The wireless communications system may further include a Wi-Fi AP 150 in communication with UEs 104 (also referred to as Wi-Fi stations (STAs)) via communication link 154, e.g., in a 5 GHz unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the UEs 104 / AP 150 may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

[0056] The electromagnetic spectrum is often subdivided, based on frequency / wavelength, into various classes, bands, channels, etc. In 5GNR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz - 7.125 GHz) and FR2 (24.25 GHz - 52.6 GHz). Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to (interchangeably) as a “sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2,129025-2544WO01Qualcomm Ref. No. 2407699WO 14 / 79 which is often referred to (interchangeably) as a “millimeter wave” band in documents and articles, despite being different from the extremely high frequency (EHF) band (30 GHz - 300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band.

[0057] The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Recent 5G NR studies have identified an operating band for these mid-band frequencies as frequency range designation FR3 (7.125 GHz - 24.25 GHz). Frequency bands falling within FR3 may inherit FR1 characteristics and / or FR2 characteristics, and thus may effectively extend features of FR1 and / or FR2 into midband frequencies. In addition, higher frequency bands are currently being explored to extend 5GNR operation beyond 52.6 GHz. For example, three higher operating bands have been identified as frequency range designations FR2-2 (52.6 GHz - 71 GHz), FR4 (71 GHz - 114.25 GHz), and FR5 (114.25 GHz - 300 GHz). Each of these higher frequency bands falls within the EHF band.

[0058] With the above aspects in mind, unless specifically stated otherwise, the term “sub-6 GHz” or the like if used herein may broadly represent frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Further, unless specifically stated otherwise, the term “millimeter wave” or the like if used herein may broadly represent frequencies that may include mid-band frequencies, may be within FR2, FR4, FR2-2, and / or FR5, or may be within the EHF band.

[0059] The base station 102 and the UE 104 may each include a plurality of antennas, such as antenna elements, antenna panels, and / or antenna arrays to facilitate beamforming. The base station 102 may transmit a beamformed signal 182 to the UE 104 in one or more transmit directions. The UE 104 may receive the beamformed signal from the base station 102 in one or more receive directions. The UE 104 may also transmit a beamformed signal 184 to the base station 102 in one or more transmit directions. The base station 102 may receive the beamformed signal from the UE 104 in one or more receive directions. The base station 102 / UE 104 may perform beam training to determine the best receive and transmit directions for each of the base station 102 / UE 104. The transmit and receive directions for the base station 102 may or may not be the same. The transmit and receive directions for the UE 104 may or may not be the same.129025-2544WO01Qualcomm Ref. No. 2407699WO 15 / 79

[0060] The base station 102 may include and / or be referred to as a gNB, Node B, eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), a TRP, network node, network entity, network equipment, or some other suitable terminology. The base station 102 can be implemented as an integrated access and backhaul (IAB) node, a relay node, a sidelink node, an aggregated (monolithic) base station with a baseband unit (BBU) (including a CU and a DU) and an RU, or as a disaggregated base station including one or more of a CU, a DU, and / or an RU. The set of base stations, which may include disaggregated base stations and / or aggregated base stations, may be referred to as next generation (NG) RAN (NG-RAN).

[0061] The core network 120 may include an Access and Mobility Management Function (AMF) 161, a Session Management Function (SMF) 162, a User Plane Function (UPF) 163, a Unified Data Management (UDM) 164, one or more location servers 168, and other functional entities. The AMF 161 is the control node that processes the signaling between the UEs 104 and the core network 120. The AMF 161 supports registration management, connection management, mobility management, and other functions. The SMF 162 supports session management and other functions. The UPF 163 supports packet routing, packet forwarding, and other functions. The UDM 164 supports the generation of authentication and key agreement (AKA) credentials, user identification handling, access authorization, and subscription management. The one or more location servers 168 are illustrated as including a Gateway Mobile Location Center (GMLC) 165 and a Location Management Function (LMF) 166. However, generally, the one or more location servers 168 may include one or more location / positioning servers, which may include one or more of the GMLC 165, the LMF 166, a position determination entity (PDE), a serving mobile location center (SMLC), a mobile positioning center (MPC), or the like. The GMLC 165 and the LMF 166 support UE location services. The GMLC 165 provides an interface for clients / applications (e.g., emergency services) for accessing UE positioning information. The LMF 166 receives measurements and assistance information from the NG-RAN and the UE 104 via the AMF 161 to compute the position of the UE 104. The NG-RAN may utilize one or more positioning methods in order to determine the position of the UE 104. Positioning the UE 104 may involve signal measurements, a position estimate, and an optional velocity computation based on the measurements.129025-2544WO01Qualcomm Ref. No. 2407699WO 16 / 79The signal measurements may be made by the UE 104 and / or the base station 102 serving the UE 104. The signals measured may be based on one or more of a satellite positioning system (SPS) 170 (e.g., one or more of a Global Navigation Satellite System (GNSS), global position system (GPS), non-terrestrial network (NTN), or other satellite position / location system), LTE signals, wireless local area network (WLAN) signals, Bluetooth signals, a terrestrial beacon system (TBS), sensor-based information (e.g., barometric pressure sensor, motion sensor), NR enhanced cell ID (NRE-CID) methods, NR signals (e.g., multi -round trip time (Multi -RTT), DL angle- of-departure (DL-AoD), DL time difference of arrival (DL-TDOA), UL time difference of arrival (UL-TDOA), and UL angle-of-arrival (UL-AoA) positioning), and / or other systems / signals / sensors.

[0062] 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 (e.g., MP3 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 any other similar functioning device. Some of the UEs 104 may be referred to as loT devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, etc.). The UE 104 may also be referred to 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, a client, or some other suitable terminology. In some scenarios, the term UE may also apply to one or more companion devices such as in a device constellation arrangement. One or more of these devices may collectively access the network and / or individually access the network.

[0063] Referring again to FIG. 1, in certain aspects, the UE 104 may have a PRACH power variation component 198 that may be configured to obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and transmit, to a network node, the plurality of random access message transmissions using the power variation pattern. In certain aspects, the base station 102 may have a PRACH power variation component 199 that may be129025-2544WO01Qualcomm Ref. No. 2407699WO 17 / 79 configured to transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and receive, from a UE, the plurality of random access message transmissions using the power variation pattern. Although the following description may be focused on 5G NR, the concepts described herein may be applicable to other similar areas, such as LTE, LTE- A, CDMA, GSM, and other wireless technologies.

[0064] FIG. 2A is a diagram 200 illustrating an example of a first subframe within a 5G NR frame structure. FIG. 2B is a diagram 230 illustrating an example of DL channels within a 5G NR subframe. FIG. 2C is a diagram 250 illustrating an example of a second subframe within a 5G NR frame structure. FIG. 2D is a diagram 280 illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplexed (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, or may be time division duplexed (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. 2A, 2C, the 5G NR 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 F is flexible for use between DL / UL, and subframe 3 being configured with slot format 1 (with all UL). While subframes 3, 4 are shown with slot formats 1, 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 infra applies also to a 5G NR frame structure that is TDD.

[0065] FIGs. 2A-2D illustrate a frame structure, and the aspects of the present disclosure may be applicable to other wireless communication technologies, which 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. Each slot may include 14 or 12 symbols, depending on whether the cyclic prefix (CP)129025-2544WO01Qualcomm Ref. No. 2407699WO 18 / 79 is normal or extended. For normal CP, each slot may include 14 symbols, and for extended CP, each slot may include 12 symbols. The symbols on DL may be CP orthogonal frequency division multiplexing (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 (for power limited scenarios; limited to a single stream transmission). The number of slots within a subframe is based on the CP and the numerology. The numerology defines the subcarrier spacing (SCS) (see Table 1). The symbol length / duration may scale with 1 / SCS.Table 1: Numerology, SCS, and CP

[0066] For normal CP (14 symbols / slot), different numerologies p 0 to 4 allow for 1, 2, 4, 8, and 16 slots, respectively, per subframe. For extended CP, the numerology 2 allows for 4 slots per subframe. Accordingly, for normal CP and numerology p, there are 14 symbols / slot and 2“ slots / subframe. The subcarrier spacing may be equal to 2 / z* 15 kHz, where . is the numerology 0 to 4. As such, the numerology p=0 has a subcarrier spacing of 15 kHz and the numerology p=4 has a subcarrier spacing of 240 kHz. The symbol length / duration is inversely related to the subcarrier spacing. FIGs. 2A-2D provide an example of normal CP with 14 symbols per slot and numerology p=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 ps. Within a set of frames, there may be one or more different bandwidth parts (BWPs) (see FIG. 2B) that are frequency division multiplexed. Each BWP may have a particular numerology and CP (normal or extended).129025-2544WO01Qualcomm Ref. No. 2407699WO 19 / 79

[0067] 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.

[0068] As illustrated in FIG. 2 A, some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include demodulation RS (DM-RS) (indicated as R for one particular configuration, 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).

[0069] FIG. 2B 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) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE including six RE groups (REGs), each REG including 12 consecutive REs in an OFDM symbol of an RB. A PDCCH within one BWP may be referred to as a control resource set (CORESET). A UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., common search space, UE-specific search space) during PDCCH monitoring occasions on the CORESET, where the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs may be located at greater and / or lower frequencies across the channel bandwidth. A primary synchronization signal (PSS) may be within symbol 2 of particular subframes of a frame. The PSS is used by a UE 104 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 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)ZPBCH block (also referred to as SS block (SSB)). The MIB provides a number of RBs in the system bandwidth and a system frame number (SFN). The physical downlink shared channel (PDSCH) carries user129025-2544WO01Qualcomm Ref. No. 2407699WO 20 / 79 data, broadcast system information not transmitted through the PBCH such as system information blocks (SIBs), and paging messages.

[0070] As illustrated in FIG. 2C, 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 frequencydependent scheduling on the UL.

[0071] FIG. 2D 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 hybrid automatic repeat request (HARQ) acknowledgment (ACK) (HARQ-ACK) feedback (i.e., one or more HARQ ACK bits indicating one or more ACK and / or negative ACK (NACK)). The PUSCH carries data, and may additionally be used to carry a buffer status report (BSR), a power headroom report (PHR), and / or UCI.

[0072] FIG. 3 is a block diagram of a base station 310 in communication with a UE 350 in an access network. In the DL, Internet protocol (IP) packets may be provided to a controller / processor 375. The controller / processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The controller / processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIBs), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter radio access technology (RAT) mobility, and measurement configuration for UE measurement129025-2544WO01Qualcomm Ref. No. 2407699WO 21 / 79 reporting; PDCP layer functionality associated with header compression / decompression, security (ciphering, deciphering, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with the transfer of upper layer packet data units (PDUs), error correction through ARQ, concatenation, segmentation, and reassembly of RLC service data units (SDUs), re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0073] The transmit (TX) processor 316 and the receive (RX) processor 370 implement layer 1 functionality associated with various signal processing functions. Layer 1, which includes a physical (PHY) layer, may include error detection on the transport channels, forward error correction (FEC) coding / decoding of the transport channels, interleaving, rate matching, mapping onto physical channels, modulation / demodulation of physical channels, and MIMO antenna processing. The TX processor 316 handles mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and / or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM stream is spatially precoded to produce multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal and / or channel condition feedback transmitted by the UE 350. Each spatial stream may then be provided to a different antenna 320 via a separate transmitter 318Tx. Each transmitter 318Tx may modulate a radio frequency (RF) carrier with a respective spatial stream for transmission.

[0074] At the UE 350, each receiver 354Rx receives a signal through its respective antenna 352. Each receiver 354Rx recovers information modulated onto an RF carrier and129025-2544WO01Qualcomm Ref. No. 2407699WO 22 / 79 provides the information to the receive (RX) processor 356. The TX processor 368 and the RX processor 356 implement layer 1 functionality associated with various signal processing functions. The RX processor 356 may perform spatial processing on the information to recover any spatial streams destined for the UE 350. If multiple spatial streams are destined for the UE 350, they may be combined by the RX processor 356 into a single OFDM symbol stream. The RX processor 356 then converts the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT). The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the base station 310. These soft decisions may be based on channel estimates computed by the channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station 310 on the physical channel. The data and control signals are then provided to the controller / processor 359, which implements layer 3 and layer 2 functionality.

[0075] The controller / processor 359 can be associated with at least one memory 360 that stores program codes and data. The at least one memory 360 may be referred to as a computer-readable medium. In the UL, the controller / processor 359 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets. The controller / processor 359 is also responsible for error detection using an ACK and / or NACK protocol to support HARQ operations.

[0076] Similar to the functionality described in connection with the DL transmission by the base station 310, the controller / processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIBs) acquisition, RRC connections, and measurement reporting; PDCP layer functionality associated with header compression / decompression, and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functionality associated with the transfer of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto TBs,129025-2544WO01Qualcomm Ref. No. 2407699WO 23 / 79 demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0077] Channel estimates derived by a channel estimator 358 from a reference signal or feedback transmitted by the base station 310 may be used by the TX processor 368 to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different antenna 352 via separate transmitters 354Tx. Each transmitter 354Tx may modulate an RF carrier with a respective spatial stream for transmission.

[0078] The UL transmission is processed at the base station 310 in a manner similar to that described in connection with the receiver function at the UE 350. Each receiver 318Rx receives a signal through its respective antenna 320. Each receiver 318Rx recovers information modulated onto an RF carrier and provides the information to a RX processor 370.

[0079] The controller / processor 375 can be associated with at least one memory 376 that stores program codes and data. The at least one memory 376 may be referred to as a computer-readable medium. In the UL, the controller / processor 375 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets. The controller / processor 375 is also responsible for error detection using an ACK and / or NACK protocol to support HARQ operations.

[0080] At least one of the TX processor 368, the RX processor 356, and the controller / processor 359 may be configured to perform aspects in connection with the PRACH power variation component 198 of FIG. 1.

[0081] At least one of the TX processor 316, the RX processor 370, and the controller / processor 375 may be configured to perform aspects in connection with the PRACH power variation component 199 of FIG. 1.

[0082] FIG. 4 illustrates example aspects of a random access procedure 400 between a UE 402 and a base station 404. The UE 402 may initiate the random access message exchange by sending, to the base station 404, a first random access message 403 (e.g., Msg 1) including a preamble in a RO. Prior to sending the first random access message 403, the UE may obtain, e.g., in system information 401 from the base station 404, random access parameters. The random access parameters, in some aspects, may include preamble format parameters, time and frequency resources, parameters for129025-2544WO01Qualcomm Ref. No. 2407699WO 24 / 79 determining root sequences and / or cyclic shifts for a random access preamble, etc. The preamble may be transmitted with an identifier, such as a Random Access radio network temporary identifier (RNTI), or RA-RNTI. The UE 402 may randomly select a random access preamble sequence, e.g., from a set of preamble sequences. If the UE 402 randomly selects the preamble sequence, the base station 404 may receive another preamble from a different UE at the same time. In some examples, a preamble sequence may be assigned to the UE 402.

[0083] The base station responds to the first random access message 403 by sending a second random access message 405 (e.g., Msg 2) using PDSCH and including a random access response (RAR). The RAR may include, e.g., an identifier of the random access preamble sent by the UE, a time advance (TA), an uplink grant for the UE to transmit data, cell radio network temporary identifier (C-RNTI) or other identifier, and / or a back-off indicator. Upon receiving the RAR (in the second random access message 405), the UE 402 may, based on the uplink grant included in the second random access message 405, transmit a third random access message 407 (e.g., Msg 3) to the base station 404, e.g., using PUSCH, that may include a RRC connection request, an RRC connection re-establishment request, or an RRC connection resume request, depending on the trigger for the initiating the random access procedure. The base station 404 may then complete the random access procedure by sending a fourth random access message 409 (e.g., Msg 4) to the UE 402, e.g., using PDCCH for scheduling and PDSCH for the message. The fourth random access message 409 may include a random access response message that includes timing advance information, contention resolution information, and / or RRC connection setup information. The UE 402 may monitor for PDCCH, e.g., with the C-RNTI. If the PDCCH is successfully decoded (or detected), the UE 402 may also decode PDSCH. The UE 402 may send HARQ feedback for any data carried in the fourth random access message. If two UEs sent a same preamble in the first random access message 403, both UEs may receive the RAR leading both UEs to send a third random access message 407. The base station 404 may resolve such a collision by being able to decode the third random access message from one of the UEs and responding with a fourth random access message to that UE. The other UE, which did not receive the fourth random access message 409, may determine that random access did not succeed and may re-attempt random access. Thus, the fourth message may be referred to as a contention resolution129025-2544WO01Qualcomm Ref. No. 2407699WO 25 / 79 message. The fourth random access message 409 may complete the random access procedure. Thus, the UE 402 may then transmit uplink communication and / or receive downlink communication with the base station 404 based on the fourth random access message 409.

[0084] In order to reduce latency or control signaling overhead, a single round trip cycle between the UE and the base station may be achieved in a 2-step RACH process. Aspects of Msg 1 and Msg 3 may be combined in a single message, e.g., which may be referred to as Msg A. The Msg A may include a random access preamble, and may also include a PUSCH transmission, e.g., such as data. The MsgA preambles may be separate from the four step preambles, yet may be transmitted in the same ROs as the preambles of the four step RACH procedure or may be transmitted in separate ROs. The PUSCH transmissions may be transmitted in PUSCH occasions (POs) that may span multiple symbols and PRBs. After the UE transmits the Msg A, the UE may wait for a response from the base station. Additionally, aspects of the Msg 2 and Msg 4 may be combined into a single message, which may be referred to as Msg B.

[0085] FIG. 5 is a call flow diagram 500 illustrating example aspects of a collisions associated with a first random access procedure between a UE 502 and a base station 504 and a second random access procedure between a UE 506 and the base station 504. The UE 502 may initiate the random access message exchange by sending, to the base station 504, a first random access message 503 (e.g., Msg 1) including a preamble in a RO. The UE 506 may initiate the random access message exchange by sending, to the base station 504, a first random access message 513 (e.g., Msg 1) including the same preamble and in the same RO as used for the first random access message 503. Prior to sending the first random access message 503 and the first random access message 513, the UEs may obtain, e.g., in system information 501 from the base station 504, random access parameters. The random access parameters, in some aspects, may include preamble format parameters, time and frequency resources, parameters for determining root sequences and / or cyclic shifts for a random access preamble, etc. The preamble may be transmitted, or associated, with an identifier, such as the RA-RNTI. As described above, the UEs may randomly select a same random access preamble sequence, e.g., from a set of preamble sequences. Additional UEs (not shown) may transmit first random access messages using129025-2544WO01Qualcomm Ref. No. 2407699WO 26 / 79 different preambles (or preamble sequences) that allow the base station to distinguish between the different first random access messages.

[0086] The base station, in some aspects, may respond to one of the first random access message 503 or the first random access message 513 by sending a second random access message 505 (e.g., Msg 2) using PDSCH and including a random access response (RAR). The RAR may include, e.g., an identifier of the random access preamble sent by the UE (e.g., the RA-RNTI), a time advance (TA), an uplink grant for the UE to transmit data, cell radio network temporary identifier (C-RNTI) or other identifier, and / or a back-off indicator. Because both UEs used the same preamble, both UEs may interpret the second random access message 505 as allocating resources for a third random access message (e.g., a Msg 3) for the UE. Upon receiving the RAR (in the second random access message 505), the UE 502 may, based on the uplink grant included in the second random access message 505, transmit a third random access message 507 (e.g., Msg 3) to the base station 504, e.g., using PUSCH, that may include a RRC connection request, an RRC connection re-establishment request, or an RRC connection resume request, depending on the trigger for the initiating the random access procedure. Similarly, upon receiving the RAR (in the second random access message 505), the UE 506 may, based on the uplink grant included in the second random access message 505, transmit a third random access message 517 (e.g., Msg 3) to the base station 504, e.g., using PUSCH, that may include a RRC connection request, an RRC connection re-establishment request, or an RRC connection resume request, depending on the trigger for the initiating the random access procedure. The base station 504 may be able to decode one of the third random access messages (e.g., the third random access message 507) and complete the random access procedure for the UE 502 by sending a fourth random access message 509 (e.g., Msg 4) to the UE 502, e.g., using PDCCH for scheduling and PDSCH for the message. The fourth random access message 509 may include a random access response message that includes timing advance information, contention resolution information, and / or RRC connection setup information. The UE 502 may monitor for PDCCH, e.g., with the C-RNTI. If the PDCCH is successfully decoded (or detected), the UE 502 may also decode PDSCH. The UE 502 may send HARQ feedback for any data carried in the fourth random access message.129025-2544WO01Qualcomm Ref. No. 2407699WO 27 / 79

[0087] For the two UEs sending a same preamble in the first random access message 503, both UEs may receive the RAR (e.g., the second random access message 505) leading both UEs to send a third random access message 507. The base station 504 may resolve such a collision by being able to decode the third random access message from one of the UEs (e.g., UE 502) and responding with a fourth random access message to that UE. The other UE, which did not receive the fourth random access message 509 (or to which the fourth random access message 509 is not addressed), may determine that random access did not succeed (e.g., based on contention resolution timer 510) and may re-attempt random access by transmitting a new first random access message 521 (e.g., Msg 1). Thus, the fourth message may be referred to as a contention resolution message. The fourth random access message 509 may complete the random access procedure. Thus, the UE 502 may then transmit uplink communication and / or receive downlink communication with the base station 504 based on the fourth random access message 509.

[0088] In some aspects of wireless communication as described above, initial access procedures may be contention based and may suffer from collisions between initial access attempts associated with and / or transmitted by different users. For example, a PRACH collision may occur when two UEs choose a same PRACH resource (e.g., a same set of time-and-frequency resources associated with a same RO and using a same preamble sequence) to transmit a first random access message (e.g., which may be referred to as a msgl, a msg 1, a Msgl, or a Msg 1). Collisions between random access messages (e.g., “Msg l”s) transmitted by two or more UEs may introduce challenges in identifying and / or distinguishing the two or more transmitting UEs. In some aspects, a base station may consider the multiple colliding random access messages as being associated with a single UE, and send out a single RAR message (e.g., which may be referred to as a msg2, a msg 2, a Msg2, or a Msg 2) including a grant for a subsequent message (e.g., which may be referred to as a msg3, a msg 3, a Msg3, or a Msg 3) associated with the random access procedure.

[0089] The UEs receiving the RAR message, in some aspects, may treat the UL grant as being for the UE as the RAR UL grant will use the preamble sequence (or PRACH resource) transmitted as a temporary ID to distinguish UEs. Accordingly, a collision at the granted UL resources for transmission of the subsequent message (e.g., msg3, a msg 3, a Msg3, or a Msg 3) may occur and contention resolution will be performed129025-2544WO01Qualcomm Ref. No. 2407699WO 28 / 79 to further distinguish between the UEs. In some aspects, this type of collision may be referred to as a sequence domain collision.

[0090] To illustrate the concept of a sequence domain collision, consider a first RO associated with 128 preambles. The collision probability may depend on a total number of users attempting initial access (e.g., transmitting first random access messages such as a Msg 1). For example, with 16 users accessing a RO (e.g., transmitting a first random access message in the first RO), the collision probability is ~11%, which may increase the latency of PRACH (e.g., the initial access procedure). To reduce the likelihood of collisions resulting in conflicting or colliding third random access messages (e.g., “Msg 3”s), each user (e.g., UE) may be configured to transmit multiple randomly selected preamble sequences in each PRACH interval (e.g., set of related ROs) either through multiple ROs associated with different time domain resources and / or different frequency domain resources, or via a same RO.

[0091] It is assumed that a base station and / or UE is capable of performing collision detection with high accuracy, and that a UE can recover accurate TA information and transmit a third random access message (or Msg 3) without collision, if there is no collision associated with at least one transmitted preamble sequence (or preamble) of the multiple randomly selected preamble sequences. In some aspects, a base station may perform collision detection, and transmit a RAR message or second random access message (e.g., a Msg 2) if there is no collision for a preamble sequence (e.g., a Msg 1) in a particular RO. Based on the multiple first random access transmissions based on the multiple randomly selected preamble sequences described above, the collision probability becomes the probability that a UE experiences collision for each transmitted preamble sequence which is significantly lower than probability of a collision associated with the single preamble transmission (e.g., a collision probability reduces from 0.11 to 0.04 with two preamble transmissions from 16 users).

[0092] In some aspects using the multiple first random access transmissions based on the multiple randomly selected preamble sequences, the network and / or the base station may not be able to determine which PRACH transmissions across multiple ROs are from the same UE. Accordingly, the use of the multiple first random access transmissions based on the multiple randomly selected preamble sequences, in some aspects, may lead to the base station to allocate a higher number, or larger amount, of UL resources for third random access messages (e.g., “Msg 3”s), particularly, in the129025-2544WO01Qualcomm Ref. No. 2407699WO 29 / 79 case of multiple successful (e.g., non-colliding) preamble sequences transmitted by a UE. For example, because the base station may not be capable of identifying related PRACH transmissions, the base station may allocate resources for a Msg 3 for each successful preamble from the UE, whereas the UE may use a single Msg 3 resource. Additionally, the performance of the use of the multiple first random access transmissions based on the multiple randomly selected preamble sequences, in some aspects, may depend on a collision detection capability of the base station and / or the UE.

[0093] Various aspects relate generally to using transmit power variations at a UE between the multiple transmitted preambles to improve the msg3 resource allocation and collision detection. Some aspects more specifically relate to adding a power-domain signature to multiple RACH / PRACH / Msg 1 transmissions (e.g., the multiple first random access transmissions based on the multiple randomly selected preamble sequences as discussed above). In some aspects, the use of the transmit power variations (e.g., an additional power-domain signature applied to multiple PRACH transmissions) may allow the base station to identify which detected preambles over multiple ROs are associated with the same UE based on the power pattern and detected delays. The base station may allocate a single set of resources for a third random access message (e.g., a “Msg 3”) and send a single Msg 2 for the multiple first random access transmissions. From the UE’s perspective, if multiple “Msg 2”s are received, it can identify which “Msg 2”s correspond to its own PRACH transmissions based on the power variation pattern (i.e., TPC) and combine them to improve TA and TPC accuracy. In some examples, a UE may be configured to obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and transmit, to a network node, the plurality of random access message transmissions using the power variation pattern. In some aspects, a network device may be configured to transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and receive, from a UE, the plurality of random access message transmissions using the power variation pattern.

[0094] For example, in some aspects, each user (e.g., UE) may transmit multiple randomly selected PRACH preambles in different time / frequency domain ROs with different transmit powers. Users transmitting multiple preambles across multiple time domain129025-2544WO01Qualcomm Ref. No. 2407699WO 30 / 79ROs, in some aspects, may avoid problems associated with a peak-to-average power ratio (PAPR) that may be caused by transmitting multiple first random access messages in different frequency domain resources associated with a same set of time domain resources. In some aspects, the power variation pattern among multiple preambles may be configured by the network (e.g., a network device, network node, base station, etc.). The power variation pattern for each preamble sequence may be indicated to the users or UEs by the network device, network node, and / or base station through RRC signaling, or may be known (e.g., preconfigured). The power variation pattern, in some aspects, may be based on a sequence selected in one of the PRACH transmissions, for example, a power variation pattern for a UE may be based on the preamble sequence randomly selected in, or for, the first PRACH transmission (e.g., the first Msg 1 in the set of Msg l’s), and the UE may then apply the power variation pattern across other related PRACH transmissions. In some aspects, the power variation patterns may be indicated through, or associated with, a linear power ramp across multiple transmissions, and each power variation pattern may be allocated, or correspond, to a set of preamble sequences.

[0095] FIG. 6A is a diagram 600 illustrating resources associated with ROs in accordance with some aspects of the disclosure. Diagram 600 illustrates that a first set of ROs (e.g., including RO 601, RO 602, RO 603, and RO 604) may each be associated with a set of time-and-frequency resources, where the set of time-and-frequency resources may be used to transmit the first random access message (e.g., msgl or Msg 1) of the random access procedure. Each RO, in some aspects, may be associated with a set of preambles. The set of preambles, in some aspects, may be the same for each RO (e.g., may use the same root sequences and cyclic shifts) or may be different across ROs. FIGs. 6B, 6C, and 6D below illustrate different implementations of transmitting two first random access messages (“Msg l”s) associated with different randomly selected preambles, where it is understood that the number of different first random access message transmissions may be larger (e.g., depending on the number of preambles and / or UEs transmitting first random access messages). While the illustrations below depict different preambles being used in different ROs, in some aspects, because the preambles are randomly selected, the same preamble may be used in different ROs while still achieving the reduction in the probability of collision across the multiple first random access messages.129025-2544WO01Qualcomm Ref. No. 2407699WO 31 / 79

[0096] FIG. 6B is a diagram 620 illustrating a transmission of multiple first random access messages (or message transmissions) within a same RO using different preambles in accordance with some aspects of the disclosure. In some aspects, a single transmission associated with a single RO (e.g., RO 601) may be generated that superimposes a fist preamble sequence 621 associated with a first transmission power (e.g., Po) and a second preamble sequence 622 associated with a second transmission power.

[0097] FIG. 6C is a diagram 640 illustrating a transmission of multiple first random access messages (or message transmissions) within different ROs using a same time resource and using different preambles in accordance with some aspects of the disclosure. In some aspects, a UE may transmit a first random access message 641 with a first transmission power (e.g., Po) in a first RO (e.g., RO 601) associated with first time resources and first frequency resources. The UE may also transmit a second random access message 642 with a second transmission power (e.g., Pi) in a second RO (e.g., RO 603) associated with the first time resources and second frequency resources. The base station may be able to associate the first random access message 641 with the second random access message 642 based on the random access messages being received with a same TA (within a known or configured margin of error or threshold difference) and based on a received power that corresponds to a known or configured power variation pattern.

[0098] FIG. 6D is a diagram 660 illustrating a transmission of multiple first random access messages (or message transmissions) within different ROs using a different time resource and using different preambles in accordance with some aspects of the disclosure. In some aspects, a UE may transmit a first random access message 661 with a first transmission power (e.g., Po) in a first RO (e.g., RO 601) associated with first time resources and first frequency resources. The UE may also transmit a second random access message 662 with a second transmission power (e.g., Pi) in a second RO (e.g., RO 602 or RO 604) associated with second time resources and one of the first frequency resources or second frequency resources. The base station may be able to associate the first random access message 661 with the second random access message 662 based on the random access messages being received with a same TA (within a known or configured margin of error or threshold difference) and based on a received power that corresponds to a known or configured power variation pattern.129025-2544WO01Qualcomm Ref. No. 2407699WO 32 / 79

[0099] FIG. 7 is a set of diagrams (e.g., diagram 700, diagram 720, and diagram 740) illustrating different power variation patterns and their association with first transmissions of a first random access message (Msg 1) in a set of multiple first random access message transmissions in accordance with some aspects of the disclosure. FIG. 7 assumes that the multiple transmissions of a first random access message occur at different times as in FIG. 6D, however, the concepts discussed in relation to FIG. 7 apply to the other implementations discussed in FIGs. 6B and 6C as well. In some aspects, using preambles transmitted via different time domain resources (e.g., at different times or via ROs associated with different time domain resources) may be associated with a better peak-to-average power ratio (PAPR) than using preambles transmitted via a same time domain resource but different frequency domain resources.

[0100] For example, diagram 700 illustrates that a first power variation pattern 710 may include a first random access message 711 associated with a first preamble and transmitted with a first power (e.g., Po), a second random access message 712 associated with a second preamble and transmitted at a later time (e.g., a next RO) with a second power (Pi,i), and a third random access message 713 associated with a third preamble and transmitted with a third power (P24), where the index (“i,j”) represents an i-th transmit power (e.g., indexed from 0 to k-1, where k is the total number of first random access messages transmitted for each random, or initial, access procedure) associated with a j-th power variation pattern. Similarly, diagram 720 illustrates that a second power variation pattern 730 may include a first random access message 721 associated with a first preamble and transmitted with a first power (e.g., Po), a second random access message 722 associated with a second preamble and transmitted at a later time (e.g., a next RO) with a second power (Pi, 2), and a third random access message 723 associated with a third preamble and transmitted with a third power (P2,2). Diagram 740 illustrates that an M-th power variation pattern 750 may include a first random access message 741 associated with a first preamble and transmitted with a first power (e.g., Po), a second random access message 742 associated with a second preamble and transmitted at a later time (e.g., a next RO) with a second power (PI,M), and a third random access message 743 associated with a third preamble and transmitted with a third power (P2,M). The different power variation patterns may be mapped to different sets of preambles. For example, the set129025-2544WO01Qualcomm Ref. No. 2407699WO 33 / 79 of preambles for which a corresponding index value modulo “M” is equal to 1 may be associated with the first power variation pattern 710, the set of preambles for which a corresponding index value modulo “M” is equal to 2 may be associated with the second power variation pattern 730, and the set of preambles for which a corresponding index value modulo “M” is equal to 0 may be associated with the M- th power variation pattern 750. For example, based on 16 possible root codes (qi to qie) and 8 possible cyclic shift values (CSi to CSs) of different possible preambles (or preamble sequences), an ordered list may be generated based on the q and CS values (e.g., [(qi, CSi), ..., (qi, CSs), ..., (qi6, CSi), ..., (qi6, CSs)]) with a position in the ordered list being used to determine a power variation patters. In some aspects, because the use of multiple first random access message transmissions is used to avoid a collision, additional parameters known (or detectable) to both the UE and the base station may be used to select power variation patterns such that UEs selecting a same preamble for a first random access message may select different power variation patterns. Additionally, or alternatively, a power variation pattern may identify a first factor or coefficient used to calculate a transmission power, where an additional coefficient and / or factor may be based on a randomly selected preamble associated with a subsequent (e.g., second or third) first random access message transmission. For example, the sets of preambles used for subsequent transmissions may further be partitioned such that each set is associated with a different factor by which the associated power (e.g., one of power Pi, 2, P2,2, Pi, 3, etc.) may be adjusted to further distinguish between UEs using a same power variation pattern.

[0101] FIG. 8A is a diagram 800 illustrating a set of preambles and timing advance values associated with different first random access messages received during a first RO in accordance with some aspects of the disclosure. As illustrated in diagram 800, for each RO, a base station may detect if any of the preambles are transmitted. For each detected preamble, the base station may detect, determine, and / or identify one or more paths, e.g., where each path may be associated with a corresponding delay (e.g., a round trip time (RTT) or TA) and a received signal strength (e.g., a power and / or associated path loss based on an assumed transmission power). For example, in diagram 800, the base station may identify a first random access message transmission 811 associated with a first preamble and a second set of first random access message transmissions 813. The first random access message transmission 811 may be129025-2544WO01Qualcomm Ref. No. 2407699WO 34 / 79 received as first random access message transmission 812 and may be associated with a TA (e.g., TAI) and a transmission power control (TPC) value based on the received power of the first random access message transmission 812. The second set of first random access message transmissions 813 may be received as a first random access message transmission 814 and as a first random access message transmission 815. The first random access message transmission 814 may be associated with a TA (e.g., TA2) and a TPC value based on the received power of the first random access message transmission 814. Similarly, the first random access message transmission 815 may be associated with a TA (e.g., TA3) and a TPC value based on the received power of the first random access message transmission 815. The TA and TPC information, in some aspects, may be used for Msg 2 transmission and Msg 3 allocation.

[0102] In some aspects, a base station may detect a collision for a preamble (e.g., preamble 2 associated with the second set of first random access message transmissions 813) based on the RTT and power delays of the paths that it detected for the preamble (e.g., based on receiving the second set of first random access message transmissions 813 as a first random access message transmission 814 and as a first random access message transmission 815 with different TA and TPC values). A collision may be associated with, or described by, a preamble (a first random access message using the preamble or preamble sequence) being detected, but the base station detecting (or having reason to believe) that the preamble has been transmitted by multiple UEs. For example, multiple paths with different delays were detected (e.g., for the second set of first random access message transmissions 813 associated with the second preamble in diagram 800).

[0103] In the case of a collision, the base station may perform any of the following. In some aspects, if the base station detects a collision for a preamble, it will discard and / or ignore the transmission (e.g., the second set of first random access message transmissions 813), and will not transmit a second random access message (e.g., a Msg 2) corresponding to that preamble. If the base station detects a collision, in some aspects, it may determine to transmit a second random access message (e.g., a Msg 2) for the preamble, with the second random access message including one of (1) Msg 3 resources, TA, and TPC information for each detected TA associated with the preamble (e.g., with the second set of first random access message transmissions 813) or (2) TA and TPC information for each detected TA in the preamble without an129025-2544WO01Qualcomm Ref. No. 2407699WO 35 / 79 indication of Msg 3 resources (e.g., without allocating Msg 3 resources). For example, the Msg 2 may include a first timing advance value for a first received Msg 1 (e.g., the first random access message transmission 814), a second timing advance value for a second received Msg 1 (e.g., the first random access message transmission 815), a first transmission power control value for the first received Msg 1 (e.g., the first random access message transmission 814), and a second transmission power control value for the second received Msg 1 (e.g., the first random access message transmission 815). The Msg 2, in some aspects, may also include a first resource allocation for a first Msg 3 associated with the first received Msg 1 (e.g., the first random access message transmission 814), and a second resource allocation for a second Msg 3 associated with the second received Msg 1 (e.g., the first random access message transmission 815). Accordingly, in the example of diagram 800, the base station may transmit a Msg 2 for the first random access message transmission 811 associated with the first preamble (e.g., including TAI, a first TPC value, and a first Msg 3 resource allocation and / or indication) and (1) omit transmission of a Msg 2 for the second set of first random access message transmissions 813 associated with the second preamble based on the detected collision, (2) transmit a Msg 2 for the second set of first random access message transmissions 813 associated with the second preamble including (a) TA2, a second TPC value, and a second Msg 3 resource allocation and / or indication for the first random access message transmission 814 and TA3, a third TPC value, and a third Msg 3 resource allocation and / or indication for the first random access message transmission 815 or (b) TA2, the second TPC value, TA3, and the third TPC value with no Msg 3 resource allocation and / or indication.

[0104] FIG. 8B is a diagram 820 illustrating a set of preambles and timing advance values associated with different first random access messages received during a first RO and a second RO in accordance with some aspects of the disclosure. As illustrated in diagram 820, for each RO, a base station may detect if any of the preambles are transmitted. For each detected preamble, the base station may detect, determine, and / or identify one or more paths, e.g., where each path may be associated with a corresponding delay (e.g., a RTT or TA) and a received signal strength (e.g., a power and / or associated path loss based on an assumed transmission power). For example, in diagram 820, in association with a first RO (e.g., RO 801), the base station may identify a first random access message transmission 831 associated with a first129025-2544WO01Qualcomm Ref. No. 2407699WO 36 / 79 preamble and a (second) first random access message transmission 833. The first random access message transmission 831 may be received as first random access message transmission 832 and may be associated with a TA (e.g., TAI) and a TPC value based on the received power, Pl, of the first random access message transmission 832. The (second) first random access message transmission 833 may be received as first random access message transmission 834 and may be associated with a TA (e.g., TA2) and a TPC value based on the received power, P2, of the first random access message transmission 834.

[0105] Similarly, in association with a second RO (e.g., RO 802 which may be associated with different time domain resources and / or different frequency domain resources from RO 801), the base station may identify a first random access message transmission 835 associated with a first preamble and a (second) first random access message transmission 837. The first random access message transmission 835 may be received as first random access message transmission 836 and may be associated with a TA (e.g., TA3) and a TPC value based on the received power, P3, of the first random access message transmission 836. The (second) first random access message transmission 837 may be received as first random access message transmission 838 and may be associated with a TA (e.g., TAI) and a TPC value based on the received power, P4, of the first random access message transmission 838.

[0106] In some aspects, the base station may attempt to identify multiple first random access message transmissions associated with a same UE. For example, the base station may map the preambles of a user across different ROs through the delay (e.g., the TA) and applied power variation (e.g., based on the TPC value and the power variation pattern applied to the transmissions of the multiple first random access messages). As discussed above, if the base station detects a preamble in a first RO, then it may identify the power variation pattern that the UE will apply in the successive PRACH transmissions (e.g., first random access message, or Msg 1, transmissions).

[0107] For example, referring to diagram 820, the base station may detect, for a first preamble, a path with a delay of TAI and power Pl associated with the first random access message transmission 832 in a first RO (e.g., RO 801), and, for a second preamble associated with a second RO (e.g., RO 802), detect a path with a delay of TAI and power P4 associated with the first random access message transmission 838. Based on the first preamble associated with the first random access message129025-2544WO01Qualcomm Ref. No. 2407699WO 37 / 79 transmission 832 in the first RO, the base station may determine and / or identify (based on a known configuration of the power variation patterns) the expected transmitted power of a next first random access message transmission from the same UE during the second RO.

[0108] Accordingly, the base station may compare TA and TPC values associated with each received first random access message transmission across the first RO and the second RO to determine if there are any first random access message transmissions that match across the ROs. For example, in diagram 820, the base station may detect and / or determine that the first random access message transmission 832 and the first random access message transmission 838 may be related to a same UE based on being associated with, or having, a same TA value (e.g., within a threshold difference that may depend on the accuracy of the measurement or the expected change over time between ROs). Based on the detected same TA value, the base station may determine if the power P4 is consistent with, or matches, a power variation pattern associated with the first preamble (e.g., the preamble associated with the first random access message transmission 832). If the power P4 (or the TPC value) matches (or is determined to be consistent with) the expected power variation pattern, the base station may determine (or assume) that the first random access message transmission 832 and the first random access message transmission 838 are associated with a same user and transmit a single Msg 2 (e.g., indicating a TA, a TPC value, and a resource allocation for a Msg 3 transmission) in response to one of the first random access message transmission 832 associated with the first RO or the first random access message transmission 838 associated with the second RO. By comparing the TA and TPC values associated with each received first random access message transmission across the first RO and the second RO to determine if there are any first random access message transmissions that match across the ROs, the base station may avoid allocating multiple Msg 3 resources to one UE (or user). In some aspects, the power variation pattern across multiple transmissions from a UE may allow the base station to detect (or more easily and / or accurately detect) the multiple transmissions from the UE and reduce the msg3 resource allocations, as without the use of the power variation pattern, a large number of UEs may transmit a PRACH (e.g., a first random access message or Msg 1) with almost the same power due to open loop power control,129025-2544WO01Qualcomm Ref. No. 2407699WO 38 / 79 leading to challenges in distinguishing sets of related first random access messages from a particular UE.

[0109] FIG. 8C is a set of diagrams illustrating different possibilities for indications of TAs and TPC values that may be received by a UE in accordance with some aspects of the disclosure. In some aspects, the indications may be received via a second random access message as described above in relation to the second random access message transmitted in response to the second set of first random access message transmissions 813 of FIG. 8A. A first case 840 illustrates that during a first RO (e.g., RO 801) a UE may transmit a first random access message 851 and receive an indication of multiple paths, where each path is associated with a set of TA and TPC values and, in some aspects, a resource allocation for a third random access message. For example, the multiple paths may include a first path associated with a received first random access message 852 associated with a first TA (e.g., TAI) and a first TPC value associated with a received power Pl and second path associated with a received first random access message 853 associated with a second TA (e.g., TA2) and a second TPC value associated with a received power P2. Without additional information, the UE may not be able to determine which TA and TPC value or resource allocation to use for a third random access message.

[0110] The UE during a second RO (e.g., RO 802) may transmit a first random access message 855 with a power based on a power variation pattern (based on the preamble sequence associated with the first random access message 851) and receive an indication of a single path associated with a received first random access message 856 associated with the second TA (e.g., TA2) and a third TPC value associated with a received power P3 (where the second TPC value and the third TPC value may be consistent based on the known power variation pattern used in transmitting the first random access message 855). Based on the matching TA and TPC values (or matching TA values and consistent TPC values), the UE may then identify TA2 as its TA value, the second and / or third TPC values as being relevant for its power control, and the second path indicated in association with the first RO as being related to the UE. Based on receiving the two different indications, the UE may use a resource allocation in one of the second random access messages. In some aspects, the second random access message associated with the first RO may not include a resource allocation for129025-2544WO01Qualcomm Ref. No. 2407699WO 39 / 79 a third random access message and the UE may use a resource allocation included in the second random access message associated with the second RO.[OHl] A second case 860 illustrates that during a first RO (e.g., RO 801) a UE may transmit a first random access message 871 and receive an indication of multiple paths, where each path is associated with a set of TA and TPC values and, in some aspects, a resource allocation for a third random access message. For example, the multiple paths may include a first path associated with a received first random access message 872 associated with a first TA (e.g., TAI) and a first TPC value associated with a received power Pl and second path associated with a received first random access message 873 associated with a second TA (e.g., TA2) and a second TPC value associated with a received power P2. Without additional information, the UE may not be able to determine which TA and TPC value or resource allocation to use for a third random access message.

[0112] The UE during a second RO (e.g., RO 802) may transmit a first random access message 875 and receive an indication of multiple paths, where each path is associated with a set of TA and TPC values and, in some aspects, a resource allocation for a third random access message. For example, the multiple paths may include a third path associated with a received first random access message 877 associated with a third TA (e.g., TA3) and a third TPC value associated with a received power P4 and a fourth path associated with a received first random access message 876 associated with the second TA (e.g., TA2) and a third TPC value associated with a received power P3 (where the second TPC value and the third TPC value may be consistent based on the known power variation pattern used in transmitting the first random access message 875). Based on the matching TA and TPC values (or matching TA values and consistent TPC values), the UE may then identify TA2 as its TA value, the second and / or third TPC values as being relevant for its power control, and both the second path indicated in association with the first RO and the fourth path indicated in association with the second RO as being related to the UE. Based on receiving the two different indications, the UE may use a resource allocation in one of the second random access messages. In some aspects, the second random access message associated with the first RO and the second random access message associated with the second RO may not include a resource allocation for a third random access129025-2544WO01Qualcomm Ref. No. 2407699WO 40 / 79 message and the UE may retransmit the first random access message (or set of first random access messages).

[0113] A third case 880 illustrates that during a first RO (e.g., RO 801) a UE may transmit a first random access message 891 and receive an indication of multiple paths, where each path is associated with a set of TA and TPC values and, in some aspects, a resource allocation for a third random access message. For example, the multiple paths may include a first path associated with a received first random access message 892 associated with a first TA (e.g., TAI) and a first TPC value associated with a received power Pl and second path associated with a received first random access message 893 associated with a second TA (e.g., TA2) and a second TPC value associated with a received power P2. Without additional information, the UE may not be able to determine which TA and TPC value or resource allocation to use for a third random access message.

[0114] The UE during a second RO (e.g., RO 802) may transmit a first random access message 895 and receive an indication of multiple paths, where each path is associated with a set of TA and TPC values and, in some aspects, a resource allocation for a third random access message. For example, the multiple paths may include a third path associated with a received first random access message 897 associated with a third TA (e.g., TA3) and a third TPC value associated with a received power P3 and a fourth path associated with a received first random access message 896 associated with a fourth TA (e.g., TA4) and a fourth TPC value associated with a received power P4. Unlike the second case 860, there is no matching TA value between the first, second, third, and fourth paths. Accordingly, the UE may be unable to determine a TA and / or TPC value or a resource allocation for a third random access message and the UE may retransmit the first random access message (or set of first random access messages). In additional to the illustrated cases above, in some aspects, a UE may receive a single second random access message (Msg 2) indicating a TA, TPC value, and resource allocation for a third random access message (Msg 3) and use the information in the second random access message to transmit the third random access message (and complete the random, or initial, access procedure) or the UE may fail to receive any second random access message and may retransmit the first random access message. The list of cases above may not be exhaustive, but is intended to129025-2544WO01Qualcomm Ref. No. 2407699WO 41 / 79 illustrate aspects of a method for avoiding collisions between first random access messages in some aspects.

[0115] Based on the above discussion, when a base station transmits second random access messages for non-colliding first random access message transmissions and omits second random access messages for colliding first random access message transmissions, if a UE detects no Msg 2 responses for any of the multiple Msg 1 transmissions (e.g., associated with multiple preambles and / or preamble sequences), then the UE may retransmit one or more additional Msg 1 transmissions with a power ramp (based on a misdetection). If the UE detects one or more Msg 2 responses for the multiple preambles it transmitted, the UE may check if the TPC values in the multiple Msg 2 responses are according to, or consistent with, the power variation pattern, and the delay values (TAs) in multiple Msg 2 responses are similar, then the UE may proceed with transmitting a Msg 3 using one of the randomly selected Msg 3 resources from the detected Msg 2 responses. However, if the TPC values in the multiple Msg 2 responses are not according to, or not consistent with, the power variation pattern, and the delay values (TAs) in multiple Msg 2 responses are not similar, the UE may choose to retransmit one or more additional Msg 1 transmissions. If the UE detects a single Msg 2 response for the multiple transmitted preambles, then the UE may proceed with transmitting a Msg 3 with the Msg 3 resources allocated and / or indicated in the detected Msg 2. The single Msg 2 response may be received when there is one Msg 1 transmission that does not experience a collision or when the base station identifies related Msg 1 transmissions to avoid over-allocating resources for Msg 3 transmissions.

[0116] In some aspects, collisions between Msg 3 transmissions from multiple UEs may occur if multiple UEs select the same preamble but the base station fails to detect the collision. In such case the base station may allocate and / or assign a Msg 3 resource for the preamble and both UEs may select the same Msg 3 resource for transmission. In some aspects, the probability of such an event may be lower when using the power variation patterns based on TPC values not matching across multiple PRACH (Msg 1) transmissions and UEs accordingly not using Msg 3 resources allocated in Msg 2s including non-matching TPC values to transmit the Msg 3.

[0117] Based on the above discussion, when a base station transmits a second random access message (e.g., an enhanced Msg 2 or multi-path Msg 2) for colliding first random129025-2544WO01Qualcomm Ref. No. 2407699WO 42 / 79 access message transmissions (e.g., Msg Is associated with multiple detected paths) that includes a TA, TPC value, and Msg 3 resource allocation for each detected path, if a UE detects no Msg 2 responses for any of the multiple Msg 1 transmissions (e.g., associated with multiple preambles and / or preamble sequences), then the UE may retransmit one or more additional Msg 1 transmissions with a power ramp (based on a misdetection). If the UE detects one or more Msg 2 responses for the multiple preambles it transmitted, the UE may check if the TPC values in the multiple Msg 2 responses are according to, or consistent with, the power variation pattern, and the delay values (TAs) in multiple Msg 2 responses are similar, then the UE may proceed with transmitting a Msg 3 using one of the randomly selected Msg 3 resources from the detected Msg 2 responses. However, if the TPC values in the multiple Msg 2 responses are not according to, or not consistent with, the power variation pattern, and the delay values (TAs) in multiple Msg 2 responses are not similar, the UE may choose to retransmit one or more additional Msg 1 transmissions. In some aspects, from the multiple Msg 2 responses, each UE may be able to compute delay (e.g., TA) and TPC values more accurately than when receiving a single Msg 2.

[0118] In order to select a TA when receiving multiple Msg 2s as described above and in relation to FIG. 8C, if a UE receives TAI and TA2 in a Msg 2 associated with a Msg 1 transmitted in a first RO and TA2 in a Msg 2 associated with a Msg 1 transmitted in a second RO, then the UE may select TA2 as the TA. In some aspects, the decision to select TA2 may be based on the power difference (or TPC value) included in the Msg 2 associated with the first RO and in the Msg 2 associated with the second RO matching the power variation pattern used for transmitting the Msg Is, and the UE may transmit a Msg 3 using the Msg 3 resources allocated to TA2 in the Msg 2 associated with the Msg 1 transmitted in the second RO. If the power difference (or TPC value) included in the Msg 2 associated with the first RO and in the Msg 2 associated with the second RO does not match with the power variation pattern used for transmitting the Msg Is, the UE may choose to retransmit the set of Msg Is.

[0119] If a UE receives TAI and TA2 in a Msg 2 associated with a Msg 1 transmitted in a first RO and TA2 and TA3 in a Msg 2 associated with a Msg 1 transmitted in a second RO, then the UE may select TA2 as the TA. In some aspects, the decision to select TA2 may be based on the power difference (or TPC value) included in the Msg 2 associated with the first RO and in the Msg 2 associated with the second RO matching129025-2544WO01Qualcomm Ref. No. 2407699WO 43 / 79 the power variation pattern used for transmitting the Msg 1 s, and the UE may transmit a Msg 3 using the Msg 3 resources allocated to TA2 in either of the Msg 2s associated with the first RO or the second RO. If the power difference (or TPC value) included in the Msg 2 associated with the first RO and in the Msg 2 associated with the second RO does not match with the power variation pattern used for transmitting the Msg Is, the UE may choose to retransmit the set of Msg Is.

[0120] If a UE receives TAI and TA2 in a Msg 2 associated with a Msg 1 transmitted in a first RO and TA3 and TA4 in a Msg 2 associated with a Msg 1 transmitted in a second RO, then the UE may not be able to map the two Msg 2s associated with the first and second ROs (or the associated Msg 1 transmissions) and may determine to retransmit the set of Msg Is.

[0121] Based on the above discussion, when a base station transmits a second random access message (e.g., an enhanced Msg 2 or multi-path Msg 2) for colliding first random access message transmissions (e.g., Msg Is associated with multiple detected paths) that includes a TA, TPC value, but does not include a Msg 3 resource allocation for the detected paths, if a UE detects no Msg 2 responses for any of the multiple Msg 1 transmissions (e.g., associated with multiple preambles and / or preamble sequences), then the UE may retransmit one or more additional Msg 1 transmissions with a power ramp (based on a misdetection). If the UE detects one or more Msg 2 responses for the multiple preambles it transmitted (where at least one includes a resource allocation for a Msg 3), the UE may check if the TPC values in the multiple Msg 2 responses are according to, or consistent with, the power variation pattern, and the delay values (TAs) in multiple Msg 2 responses are similar, then the UE may proceed with transmitting a Msg 3 using one of the randomly selected Msg 3 resources from the detected Msg 2 responses. However, if the TPC values in the multiple Msg 2 responses are not according to, or not consistent with, the power variation pattern, and the delay values (TAs) in multiple Msg 2 responses are not similar, the UE may choose to retransmit one or more additional Msg 1 transmissions. In some aspects, from the multiple Msg 2 responses, each UE may be able to compute delay (e.g., TA) and TPC values more accurately than when receiving a single Msg 2. If none of the detected one or more Msg 2 responses includes a resource allocation for the Msg 3 (e.g., if there is a collision in all the ROs in which it transmitted a Msg 1), the UE may129025-2544WO01Qualcomm Ref. No. 2407699WO 44 / 79 be able to resolve the collision (identify its TA and TPC values), but may not be able to transmit the Msg 3 as it has not received a resource allocation.

[0122] FIG. 9 is a call flow diagram 900 illustrating a method of wireless communication in accordance with some aspects of the disclosure. The method is illustrated in relation to a base station 902 (e.g., as an example of a network device or network node that may include one or more components of a disaggregated base station) in communication with a UE 904 (e.g., as an example of a wireless device). A set of UEs 906 is also illustrated in FIG. 9 and the set of UEs 906 may include a set of UEs that are generally equivalent to UE 904. The functions ascribed to the base station 902, in some aspects, may be performed by one or more components of a network entity, a network node, or a network device (a single network entity / node / device or a disaggregated network entity / node / device as described above in relation to FIG. 1). Similarly, the functions ascribed to the UE 904, in some aspects, may be performed by one or more components of a wireless device supporting communication with a network entity / node / device. Accordingly, references to “transmitting” in the description below may be understood to refer to a first component of the base station 902 (or the UE 904) outputting (or providing) an indication of the content of the transmission to be transmitted by a different component of the base station 902 (or the UE 904). Similarly, references to “receiving” in the description below may be understood to refer to a first component of the base station 902 (or the UE 904) receiving a transmitted signal and outputting (or providing) the received signal (or information based on the received signal) to a different component of the base station 902 (or the UE 904).

[0123] At 912, the UE 904 may obtain a power variation configuration. In some aspects, the power variation configuration may be pre-configured or known at the UE 904. In some aspects, the base station 902 may transmit, and the UE 904 (to obtain the power variation configuration at 912) may receive, power variation configuration 910. In some aspects, the power variation configuration 910 may be transmitted and / or received via RRC signaling. In some aspects, the power variation configuration 910 may indicate a power variation pattern for a plurality of random access message transmissions (e.g., first random access message or Msg 1 transmissions) and the power variation pattern may be a first power variation pattern of a plurality of power variation patterns. The random access message configuration (e.g., the power129025-2544WO01Qualcomm Ref. No. 2407699WO 45 / 79 variation configuration 910) may indicate the plurality of power variation patterns. In some aspects, each power variation pattern of the plurality of power variation patterns may be associated with a set of preamble sequences as illustrated in relation to FIG. 7.

[0124] The UE 904 may transmit, and the base station 902 may receive (at 916), a plurality of random access message (Msg 1) transmissions 914 via a plurality of ROs. In some aspects, the base station may receive additional pluralities of random access message (Msg 1) transmissions from one or more additional UEs in the set of UEs 906. Each random access message may be associated with a randomly selected preamble sequence used to temporarily identify individual UEs and different UEs may select the same preamble sequences leading to a collision as described above in relation to at least FIG. 5. The plurality of random access message (Msg 1) transmissions 914 may use the first power variation pattern based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message (Msg 1) transmissions.

[0125] At 918, the base station 902 may detect related Msg 1 transmissions and omit one or more Msg 2 transmissions associated with related Msg 1 transmissions. For example, the related Msg 1 transmissions may be Msg 1 transmissions transmitted from the same UE (e.g., related to a same plurality of random access message (Msg 1) transmissions 914) and the base station 902 may, at 918, identify one or more of the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1 transmissions and / or based on a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern and omit all but one Msg 2 transmissions in response to the plurality of Msg 1 transmissions. In some aspects, the related Msg 1 transmissions may be Msg 1 transmissions using a same preamble sequence and associated with a same RO. For example, the additional pluralities of random access message (Msg 1) transmissions from one or more additional UEs in the set of UEs 906 (e.g., an additional plurality of Msg 1 transmissions received from at least one additional UE) may use an additional power variation pattern, and at least one Msg 1 transmission in the plurality of random access message (Msg 1) transmissions 914 may be associated with a same129025-2544WO01Qualcomm Ref. No. 2407699WO 46 / 79 preamble and a same random access occasion as at least one additional Msg 1 transmission of the additional plurality of Msg 1 transmissions and the base station 902 may determine, at 918, to omit, based on the association with the same preamble and the same random access occasion (e.g., based on the detected collision and / or the identification of the two Msg 1 transmissions as being related), a transmission of a second Msg 2 for the at least one Msg 1 transmission and the at least one additional Msg 1.

[0126] Based on the detection at 918, the base station 902 may transmit, and the UE 904 and the set of UEs 906 may receive, one or more second random access message (Msg 2) transmissions 920. Each of the one or more second random access message (Msg 2) transmissions 920 may be in response to one or more Msg 1 transmissions (where the Msg 2 may be in response to multiple Msg 1 transmissions when the multiple Msg 1 transmissions are associated with a same preamble sequence and RO). In some aspects, the one or more second random access message (Msg 2) transmissions 920 in response to the plurality of random access message (Msg 1) transmissions 914 may include a single Msg 2 transmitted in response to the plurality of random access message (Msg 1) transmissions 914 based on identifying the plurality of random access message (Msg 1) transmissions 914 as being related and in order to avoid overallocating resources for a single Msg 3 to be transmitted by the UE 904. In some aspects, the one or more second random access message (Msg 2) transmissions 920 may not include responses to the plurality of random access message (Msg 1) transmissions 914 or the additional pluralities of random access message (Msg 1) transmissions that experience a collision.

[0127] In some aspects, e.g., when a collision is detected by the base station 902, the one or more second random access message (Msg 2) transmissions 920 (e.g., for the Msg 1 transmissions experiencing a collision) may include a first timing advance value for at least one Msg 1 transmission (e.g., at least one of the plurality of random access message (Msg 1) transmissions 914), a second timing advance value for the at least one additional Msg 1 transmission (e.g., at least one of the additional pluralities of random access message (Msg 1) transmissions), a first transmission power control value for the at least one Msg 1 transmission (e.g., at least one of the plurality of random access message (Msg 1) transmissions 914), and a second transmission power control value for the at least one additional Msg 1 transmission (e.g., at least one of129025-2544WO01Qualcomm Ref. No. 2407699WO 47 / 79 the additional pluralities of random access message (Msg 1) transmissions). In some aspects, the one or more second random access message (Msg 2) transmissions 920 (e.g., for the Msg 1 transmissions experiencing a collision) may include a first resource allocation for a first Msg 3 associated with the at least one Msg 1 transmission (e.g., at least one of the plurality of random access message (Msg 1) transmissions 914) and a second resource allocation for a second Msg 3 associated with the at least one additional Msg 1 transmission (e.g., at least one of the additional pluralities of random access message (Msg 1) transmissions).

[0128] At 922, the UE 904 may select resources for a third random access message (Msg 3) transmission. The selection may be based on the one or more second random access message (Msg 2) transmissions 920 received from the base station 902. In some aspects, the UE 904 may, at 922, select a resource for transmitting the third random access message (Msg 3) from a resource allocation indicated in one of the one or more second random access message (Msg 2) transmissions 920. In some aspects, the selection may be based on identifying, in the one of the one or more second random access message (Msg 2) transmissions 920, a common timing advance value and a set of transmission power control values that are consistent with the power variation pattern. In some aspects, the resource allocation indicated in the one of the one of the one or more second random access message (Msg 2) transmissions 920 may be associated with at least the common timing advance value, and in some aspects may further be associated with the consistent TPC value.

[0129] Based on the resources selected at 922, the UE 904 may transmit, and the base station 902 may receive, a third random access message 924. Additional aspects of the random access procedure may proceed as normal. For example, if the UE is unable to identify resources at 922, or fails to receive a second random access message allocating resources for the third random access message within a time window, the UE 904 may initiate a new random access procedure as described in relation to at least FIG. 5.

[0130] FIG. 10 is a flowchart 1000 of a method of wireless communication. The method may be performed by a wireless device such as a UE (e.g., the UE 104, 402, 502, 506, 904; the apparatus 1404). At 1002, the UE may obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions. For example, 1002 may be performed by application129025-2544WO01Qualcomm Ref. No. 2407699WO 48 / 79 processor(s) 1406, cellular baseband processor(s) 1424, transceiver s) 1422, antenna(s) 1480, and / or PRACH power variation component 198 of FIG. 14. Obtaining the random access message configuration, in some aspects, may include receiving the random access message configuration via RRC signaling. In some aspects, the power variation pattern may be a first power variation pattern of a plurality of power variation patterns. The random access message configuration, in some aspects, may indicate the plurality of power variation patterns, where each power variation pattern of the plurality of power variation patterns may be associated with a set of preamble sequences. For example, referring to FIGs. 7 and 9, the UE 904 may, at 912, obtain a power variation configuration such as by receiving the power variation configuration 910, where the power variation configuration may include a set of power variation patterns and a mapping to particular preamble sequences as illustrated in FIG. 7.

[0131] At 1004, the UE may transmit, to a network node, the plurality of random access message transmissions using the power variation pattern. For example, 1004 may be performed by application processor(s) 1406, cellular baseband processor(s) 1424, transceiver(s) 1422, antenna(s) 1480, and / or PRACH power variation component 198 of FIG. 14. In some aspects, using the first power variation pattern for the plurality of random access message transmissions may be based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions. In some aspects, the plurality of random access message transmissions may be associated with a plurality of different ROs. For example, referring to FIGs. 7 and 9, the UE 904 may transmit the plurality of random access message (Msg 1) transmissions 914 using the first power variation pattern based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message (Msg 1) transmissions, where the power variation pattern may be identified as illustrated in FIG. 7.

[0132] In some aspects, the UE may receive at least one second random access message (Msg 2) based on at least one Msg 1 transmission in the plurality of Msg 1 transmissions. In some aspects, receiving the at least one Msg 2 at 1006 may include receiving multiple second random access messages. The at least one Msg 2, in some129025-2544WO01Qualcomm Ref. No. 2407699WO 49 / 79 aspects, may include a first timing advance value for a first received Msg 1, a second timing advance value for a second received Msg 1, a first transmission power control value for the first received Msg 1, and a second transmission power control value for the second received Msg 1. In some aspects, the at least one Msg 2 may include a first resource allocation for a first Msg 3 associated with the first received Msg 1, and a second resource allocation for a second Msg 3 associated with the second received Msg 1. The at least one Msg 2, in some aspects, may include a timing advance value for a first received Msg 1, a first transmission power control value for the first received Msg 1, and a first resource allocation for a first Msg 3 associated with the first received Msg 1 based on the first received Msg 1 not experiencing a collision. For example, referring to FIGs. 8C and 9, the UE 904 may receive the one or more second random access message (Msg 2) transmissions 920 indicating the TA and TPC values and the resource allocation for a related Msg 3 as described in relation to FIGs. 8C and 9.

[0133] The UE, in some aspects, may select, from a resource allocation indicated in one of the multiple second random access messages, a resource for transmitting a third random access message (Msg 3). In some aspects, selecting the resource for transmitting the third random access message (Msg 3) may include, at 1009, identifying, in the multiple second random access messages, a common timing advance value and a set of transmission power control values that are consistent with the power variation pattern. The resource allocation indicated in the one of the multiple second random access messages, in some aspects, may by associated with at least the common timing advance value. In some aspects, the resource allocation indicated in the one of the multiple second random access messages may further be associated with one of the transmission power control values that are consistent with the power variation pattern. For example, referring to FIGs. 8C and 9, the UE 904 may, at 922, select resources for a third random access message (Msg 3) transmission based on receiving the one or more second random access message (Msg 2) transmissions 920 indicating the TA and TPC values and the resource allocation for a related Msg 3 as described in relation to FIGs. 8C and 9. In some aspects., the UE may transmit, via the selected resource, the Msg 3. Referring to FIG. 9, for example, the UE 904 may transmit the third random access message 924.129025-2544WO01Qualcomm Ref. No. 2407699WO 50 / 79

[0134] FIG. 11 is a flowchart 1100 of a method of wireless communication. The method may be performed by a wireless device such as a UE (e.g., the UE 104, 402, 502, 506, 904; the apparatus 1404). At 1102, the UE may obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions. For example, 1102 may be performed by application processor(s) 1406, cellular baseband processor(s) 1424, transceiver s) 1422, antenna(s) 1480, and / or PRACH power variation component 198 of FIG. 14. Obtaining the random access message configuration, in some aspects, may include receiving the random access message configuration via RRC signaling. In some aspects, the power variation pattern may be a first power variation pattern of a plurality of power variation patterns. The random access message configuration, in some aspects, may indicate the plurality of power variation patterns, where each power variation pattern of the plurality of power variation patterns may be associated with a set of preamble sequences. For example, referring to FIGs. 7 and 9, the UE 904 may, at 912, obtain a power variation configuration such as by receiving the power variation configuration 910, where the power variation configuration may include a set of power variation patterns and a mapping to particular preamble sequences as illustrated in FIG. 7.

[0135] At 1104, the UE may transmit, to a network node, the plurality of random access message transmissions using the power variation pattern. For example, 1104 may be performed by application processor(s) 1406, cellular baseband processor(s) 1424, transceiver(s) 1422, antenna(s) 1480, and / or PRACH power variation component 198 of FIG. 14. In some aspects, using the first power variation pattern for the plurality of random access message transmissions may be based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions. In some aspects, the plurality of random access message transmissions may be associated with a plurality of different ROs. For example, referring to FIGs. 7 and 9, the UE 904 may transmit the plurality of random access message (Msg 1) transmissions 914 using the first power variation pattern based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access129025-2544WO01Qualcomm Ref. No. 2407699WO 51 / 79 message (Msg 1) transmissions, where the power variation pattern may be identified as illustrated in FIG. 7.

[0136] At 1106, the UE may receive at least one second random access message (Msg 2) based on at least one Msg 1 transmission in the plurality of Msg 1 transmissions. For example, 1106 may be performed by application processor(s) 1406, cellular baseband processor(s) 1424, transceiver(s) 1422, antenna(s) 1480, and / or PRACH power variation component 198 of FIG. 14. In some aspects, receiving the at least one Msg 2 at 1106 may include receiving multiple second random access messages. The at least one Msg 2, in some aspects, may include a first timing advance value for a first received Msg 1, a second timing advance value for a second received Msg 1, a first transmission power control value for the first received Msg 1, and a second transmission power control value for the second received Msg 1. In some aspects, the at least one Msg 2 may include a first resource allocation for a first Msg 3 associated with the first received Msg 1, and a second resource allocation for a second Msg 3 associated with the second received Msg 1. The at least one Msg 2, in some aspects, may include a timing advance value for a first received Msg 1, a first transmission power control value for the first received Msg 1, and a first resource allocation for a first Msg 3 associated with the first received Msg 1 based on the first received Msg 1 not experiencing a collision. For example, referring to FIGs. 8C and 9, the UE 904 may receive the one or more second random access message (Msg 2) transmissions 920 indicating the TA and TPC values and the resource allocation for a related Msg 3 as described in relation to FIGs. 8C and 9.

[0137] At 1108, the UE may select, from a resource allocation indicated in one of the multiple second random access messages, a resource for transmitting a third random access message (Msg 3). In some aspects, selecting the resource for transmitting the third random access message (Msg 3) at 1108 may include, at 1109, identifying, in the multiple second random access messages, a common timing advance value and a set of transmission power control values that are consistent with the power variation pattern. For example, 1108 and 1109 may be performed by application processor(s) 1406, cellular baseband processor(s) 1424, transceiver s) 1422, antenna(s) 1480, and / or PRACH power variation component 198 of FIG. 14. The resource allocation indicated in the one of the multiple second random access messages, in some aspects, may by associated with at least the common timing advance value. In some aspects,129025-2544WO01Qualcomm Ref. No. 2407699WO 52 / 79 the resource allocation indicated in the one of the multiple second random access messages may further be associated with one of the transmission power control values that are consistent with the power variation pattern. For example, referring to FIGs. 8C and 9, the UE 904 may, at 922, select resources for a third random access message (Msg 3) transmission based on receiving the one or more second random access message (Msg 2) transmissions 920 indicating the TA and TPC values and the resource allocation for a related Msg 3 as described in relation to FIGs. 8C and 9.

[0138] At 1110, the UE may transmit, via the selected resource, the Msg 3. For example, 1110 may be performed by application processor(s) 1406, cellular baseband processor(s) 1424, transceiver(s) 1422, antenna(s) 1480, and / or PRACH power variation component 198 of FIG. 14. Referring to FIG. 9, for example, the UE 904 may transmit the third random access message 924.

[0139] FIG. 12 is a flowchart 1200 of a method of wireless communication. The method may be performed by a network node or network device such as a base station (e.g., the base station 102, 404, 504, 902; the network entity 1402, 1502, _1260). At 1202, the base station may transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions. For example, 1202 may be performed by CU processor(s) 1512, DU processor(s) 1532, RU processor(s) 1542, transceiver(s) 1546, antenna(s) 1580, and / or PRACH power variation component 199 of FIG. 15. Transmitting the random access message configuration, in some aspects, may include transmitting the random access message configuration via RRC signaling. In some aspects, the power variation pattern may be a first power variation pattern of a plurality of power variation patterns. The random access message configuration, in some aspects, may indicate the plurality of power variation patterns, where each power variation pattern of the plurality of power variation patterns may be associated with a set of preamble sequences. For example, referring to FIGs. 7 and 9, the base station 902 may transmit the power variation configuration 910, where the power variation configuration may include a set of power variation patterns and a mapping to particular preamble sequences as illustrated in FIG. 7.

[0140] At 1204, the base station may receive, from a UE, the plurality of random access message transmissions using the power variation pattern. For example, 1204 may be performed by CU processor(s) 1512, DU processor(s) 1532, RU processor(s) 1542,129025-2544WO01Qualcomm Ref. No. 2407699WO 53 / 79 transceiver(s) 1546, antenna(s) 1580, and / or PRACH power variation component 199 of FIG. 15. In some aspects, the first power variation pattern for the plurality of random access message transmissions may be based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions. In some aspects, the plurality of random access message transmissions may be associated with a plurality of different ROs. For example, referring to FIGs. 7 and 9, the base station 902 may, at 916, receive the plurality of random access message (Msg 1) transmissions 914 using the first power variation pattern based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message (Msg 1) transmissions, where the power variation pattern may be identified as illustrated in FIG. 7.

[0141] In some aspects, the base station may receive, from at least one additional UE, an additional plurality of Msg 1 transmissions using an additional power variation pattern. In some aspects, the at least one Msg 1 transmission in the plurality of Msg 1 transmissions may be associated with a same preamble and a same random access occasion as at least one additional Msg 1 transmission of the additional plurality of Msg 1 transmissions. For example, referring to FIGs. 7 and 9, the base station 902 may, at 916, receive the base station may receive additional pluralities of random access message (Msg 1) transmissions from one or more additional UEs in the set of UEs 906, where the power variation pattern associated with each additional plurality of random access message (Msg 1) transmissions may be identified as illustrated in FIG. 7.

[0142] The base station, in some aspects, may omit, based on the association with the same preamble and the same random access occasion, a transmission of a second Msg 2 for the at least one Msg 1 transmission and the at least one additional Msg 1. In some aspects, instead of omitting the transmission of the second Msg 2, the base station may transmit a modified Msg 2 indicating a first timing advance value for the at least one Msg 1 transmission, a second timing advance value for the at least one additional Msg 1 transmission, a first transmission power control value for the at least one Msg 1 transmission, and a second transmission power control value for the at least one additional Msg 1 transmission. The modified Msg 2, in some aspects, may include a129025-2544WO01Qualcomm Ref. No. 2407699WO 54 / 79 first resource allocation for a first Msg 3 associated with the at least one Msg 1 transmission and a second resource allocation for a second Msg 3 associated with the at least one additional Msg 1 transmission. For example, referring to FIGs. 8C and 9, the base station 902 may, at 922, detect related Msg 1 transmissions and omit one or more Msg 2 transmissions associated with related Msg 1 transmissions, e.g., if at least one Msg 1 transmission in the plurality of random access message (Msg 1) transmissions 914 is associated with a same preamble and a same random access occasion as at least one additional Msg 1 transmission of the additional plurality of Msg 1 transmissions, the base station 902 may determine, at 918, to omit, based on the association with the same preamble and the same random access occasion (e.g., based on the detected collision and / or the identification of the two Msg 1 transmissions as being related), a transmission of a second Msg 2 for the at least one Msg 1 transmission and the at least one additional Msg 1 transmission.

[0143] In some aspects, the base station may identify the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1 transmissions and a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern. The base station may determine to transmit, in response to the plurality of Msg 1 transmissions, a is a single Msg 2. For example, referring to FIGs. 8C and 9, the base station 902 may, at 922, detect related Msg 1 transmissions and omit one or more Msg 2 transmissions associated with related Msg 1 transmissions, e.g., the base station may identify one or more of the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1 transmissions and / or based on a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern and omit all but one Msg 2 transmission in response to the plurality of Msg 1 transmissions.

[0144] The base station, in some aspects, may transmit at least one second random access message (Msg 2) based on a first Msg 1 transmission in the plurality of Msg 1 transmissions. In some aspects, the at least one second random access message (Msg 2) based on a first Msg 1 transmission in the plurality of Msg 1 transmissions may be a single Msg 2 transmitted in response to the plurality of Msg 1 transmissions (e.g., based on identifying the plurality of Msg 1 transmissions as being related).129025-2544WO01Qualcomm Ref. No. 2407699WO 55 / 79Transmitting the at least one Msg 2, in some aspects, may include transmitting multiple second random access messages in response to the plurality of Msg 1 transmissions. In some aspects, the at least one transmitted Msg 2 of the multiple second random access messages is associated with the at least one Msg 1 transmission and includes a first timing advance value for the at least one Msg 1 transmission, a second timing advance value for the at least one additional Msg 1 transmission, a first transmission power control value for the at least one Msg 1 transmission, and a second transmission power control value for the at least one additional Msg 1 transmission. The at least one transmitted Msg 2, in some aspects, may include a first resource allocation for a first Msg 3 associated with the at least one Msg 1 transmission and a second resource allocation for a second Msg 3 associated with the at least one additional Msg 1 transmission. For example, referring to FIGs. 8C and 9, the base station 902 may transmit the one or more second random access message (Msg 2) transmissions 920 indicating the TA and TPC values and the resource allocation for a related Msg 3 as described in relation to FIGs. 8C and 9.

[0145] FIG. 13 is a flowchart 1300 of a method of wireless communication. The method may be performed by a network node or network device such as a base station (e.g., the base station 102, 404, 504, 902; the network entity 1402, 1502, _1260). At 1302, the base station may transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions. For example, 1302 may be performed by CU processor(s) 1512, DU processor(s) 1532, RU processor(s) 1542, transceiver(s) 1546, antenna(s) 1580, and / or PRACH power variation component 199 of FIG. 15. Transmitting the random access message configuration, in some aspects, may include transmitting the random access message configuration via RRC signaling. In some aspects, the power variation pattern may be a first power variation pattern of a plurality of power variation patterns. The random access message configuration, in some aspects, may indicate the plurality of power variation patterns, where each power variation pattern of the plurality of power variation patterns may be associated with a set of preamble sequences. For example, referring to FIGs. 7 and 9, the base station 902 may transmit the power variation configuration 910, where the power variation configuration may include a set of power variation patterns and a mapping to particular preamble sequences as illustrated in FIG. 7.129025-2544WO01Qualcomm Ref. No. 2407699WO 56 / 79

[0146] At 1304, the base station may receive, from a UE, the plurality of random access message transmissions using the power variation pattern. For example, 1304 may be performed by CU processor(s) 1512, DU processor(s) 1532, RU processor(s) 1542, transceiver(s) 1546, antenna(s) 1580, and / or PRACH power variation component 199 of FIG. 15. In some aspects, the first power variation pattern for the plurality of random access message transmissions may be based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions. In some aspects, the plurality of random access message transmissions may be associated with a plurality of different ROs. For example, referring to FIGs. 7 and 9, the base station 902 may, at 916, receive the plurality of random access message (Msg 1) transmissions 914 using the first power variation pattern based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message (Msg 1) transmissions, where the power variation pattern may be identified as illustrated in FIG. 7.

[0147] At 1306, the base station may receive, from at least one additional UE, an additional plurality of Msg 1 transmissions using an additional power variation pattern. For example, 1306 may be performed by CU processor(s) 1512, DU processor(s) 1532, RU processor(s) 1542, transceiver(s) 1546, antenna(s) 1580, and / or PRACH power variation component 199 of FIG. 15. In some aspects, the at least one Msg 1 transmission in the plurality of Msg 1 transmissions may be associated with a same preamble and a same random access occasion as at least one additional Msg 1 transmission of the additional plurality of Msg 1 transmissions. For example, referring to FIGs. 7 and 9, the base station 902 may, at 916, receive the base station may receive additional pluralities of random access message (Msg 1) transmissions from one or more additional UEs in the set of UEs 906, where the power variation pattern associated with each additional plurality of random access message (Msg 1) transmissions may be identified as illustrated in FIG. 7.

[0148] At 1308, the base station may omit, based on the association with the same preamble and the same random access occasion, a transmission of a second Msg 2 for the at least one Msg 1 transmission and the at least one additional Msg 1. For example, 1308 may be performed by CU processor(s) 1512, DU processor(s) 1532, RU processor(s)129025-2544WO01Qualcomm Ref. No. 2407699WO 57 / 791542, transceiver(s) 1546, antenna(s) 1580, and / or PRACH power variation component 199 of FIG. 15. In some aspects, instead of omitting the transmission of the second Msg 2, the base station may transmit a modified Msg 2 indicating a first timing advance value for the at least one Msg 1 transmission, a second timing advance value for the at least one additional Msg 1 transmission, a first transmission power control value for the at least one Msg 1 transmission, and a second transmission power control value for the at least one additional Msg 1 transmission. The modified Msg 2, in some aspects, may include a first resource allocation for a first Msg 3 associated with the at least one Msg 1 transmission and a second resource allocation for a second Msg 3 associated with the at least one additional Msg 1 transmission. For example, referring to FIGs. 8C and 9, the base station 902 may, at 922, detect related Msg 1 transmissions and omit one or more Msg 2 transmissions associated with related Msg 1 transmissions, e.g., if at least one Msg 1 transmission in the plurality of random access message (Msg 1) transmissions 914 is associated with a same preamble and a same random access occasion as at least one additional Msg 1 transmission of the additional plurality of Msg 1 transmissions, the base station 902 may determine, at 918, to omit, based on the association with the same preamble and the same random access occasion (e.g., based on the detected collision and / or the identification of the two Msg 1 transmissions as being related), a transmission of a second Msg 2 for the at least one Msg 1 transmission and the at least one additional Msg 1 transmission.

[0149] At 1310, the base station may identify the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1 transmissions and a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern. For example, 1310 may be performed by CU processor(s) 1512, DU processor(s) 1532, RU processor(s) 1542, transceiver(s) 1546, antenna(s) 1580, and / or PRACH power variation component 199 of FIG. 15. The base station may determine to transmit, in response to the plurality of Msg 1 transmissions, a is a single Msg 2. For example, referring to FIGs. 8C and 9, the base station 902 may, at 922, detect related Msg 1 transmissions and omit one or more Msg 2 transmissions associated with related Msg 1 transmissions, e.g., the base station may identify one or more of the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1129025-2544WO01Qualcomm Ref. No. 2407699WO 58 / 79 transmissions and / or based on a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern and omit all but one Msg 2 transmission in response to the plurality of Msg 1 transmissions.

[0150] At 1312, the base station may transmit at least one second random access message (Msg 2) based on a first Msg 1 transmission in the plurality of Msg 1 transmissions. For example, 1312 may be performed by CU processor(s) 1512, DU processor(s) 1532, RU processor(s) 1542, transceiver s) 1546, antenna(s) 1580, and / or PRACH power variation component 199 of FIG. 15. In some aspects, the at least one second random access message (Msg 2) based on a first Msg 1 transmission in the plurality of Msg 1 transmissions may be a single Msg 2 transmitted in response to the plurality of Msg 1 transmissions (e.g., based on identifying the plurality of Msg 1 transmissions as being related at 1310). Transmitting the at least one Msg 2 at 1312, in some aspects, may include transmitting multiple second random access messages in response to the plurality of Msg 1 transmissions. In some aspects, the at least one transmitted Msg 2 of the multiple second random access messages is associated with the at least one Msg 1 transmission and includes a first timing advance value for the at least one Msg 1 transmission, a second timing advance value for the at least one additional Msg 1 transmission, a first transmission power control value for the at least one Msg 1 transmission, and a second transmission power control value for the at least one additional Msg 1 transmission. The at least one transmitted Msg 2, in some aspects, may include a first resource allocation for a first Msg 3 associated with the at least one Msg 1 transmission and a second resource allocation for a second Msg 3 associated with the at least one additional Msg 1 transmission. For example, referring to FIGs. 8C and 9, the base station 902 may transmit the one or more second random access message (Msg 2) transmissions 920 indicating the TA and TPC values and the resource allocation for a related Msg 3 as described in relation to FIGs. 8C and 9.

[0151] FIG. 14 is a diagram 1400 illustrating an example of a hardware implementation for an apparatus 1404. The apparatus 1404 may be a UE, a component of a UE, or may implement UE functionality. In some aspects, the apparatus 1404 may include at least one cellular baseband processor 1424 (also referred to as a modem) coupled to one or more transceivers 1422 (e.g., cellular RF transceiver). The cellular baseband processor(s) 1424 may include at least one on-chip memory 1424'. In some aspects,129025-2544WO01Qualcomm Ref. No. 2407699WO 59 / 79 the apparatus 1404 may further include one or more subscriber identity modules (SIM) cards 1420 and at least one application processor 1406 coupled to a secure digital (SD) card 1408 and a screen 1410. The application processor(s) 1406 may include on-chip memory 1406'. In some aspects, the apparatus 1404 may further include a Bluetooth module 1412, a WLAN module 1414, an SPS module 1416 (e.g., GNSS module), one or more sensor modules 1418 (e.g., barometric pressure sensor / altimeter; motion sensor such as inertial measurement unit (IMU), gyroscope, and / or accelerometer(s); light detection and ranging (LIDAR), radio assisted detection and ranging (RADAR), sound navigation and ranging (SONAR), magnetometer, audio and / or other technologies used for positioning), additional memory modules 1426, a power supply 1430, and / or a camera 1432. The Bluetooth module 1412, the WLAN module 1414, and the SPS module 1416 may include an on-chip transceiver (TRX) (or in some cases, just a receiver (RX)). The Bluetooth module 1412, the WLAN module 1414, and the SPS module 1416 may include their own dedicated antennas and / or utilize one or more antennas 1480 for communication. The cellular baseband processor(s) 1424 communicates through the transceiver(s) 1422 via the one or more antennas 1480 with the UE 104 and / or with an RU associated with a network entity 1402. The cellular baseband processor(s) 1424 and the application processor(s) 1406 may each include a computer-readable medium / memory 1424', 1406', respectively. The additional memory modules 1426 may also be considered a computer-readable medium / memory. Each computer-readable medium / memory 1424', 1406', 1426 may be non -transitory. The cellular baseband processor(s) 1424 and the application processor(s) 1406 are each responsible for general processing, including the execution of software stored on the computer-readable medium / memory. The software, when executed by the cellular baseband processor(s) 1424 / application processor(s) 1406, causes the cellular baseband processor(s) 1424 / application processor(s) 1406 to perform the various functions described supra. The cellular baseband processor(s) 1424 and the application processor(s) 1406 are configured to perform the various functions described supra based at least in part of the information stored in the memory. That is, the cellular baseband processor(s) 1424 and the application processor(s) 1406 may be configured to perform a first subset of the various functions described supra without information stored in the memory and may be configured to perform a second subset of the various functions described supra based on the129025-2544WO01Qualcomm Ref. No. 2407699WO 60 / 79 information stored in the memory. The computer-readable medium / memory may also be used for storing data that is manipulated by the cellular baseband processor(s) 1424 / application processor(s) 1406 when executing software. The cellular baseband processor(s) 1424 / application processor(s) 1406 may be a component of the UE 350 and may include the at least one memory 360 and / or at least one of the TX processor 368, the RX processor 356, and the controller / processor 359. In one configuration, the apparatus 1404 may be at least one processor chip (modem and / or application) and include just the cellular baseband processor(s) 1424 and / or the application processor(s) 1406, and in another configuration, the apparatus 1404 may be the entire UE (e.g., see UE 350 of FIG. 3) and include the additional modules of the apparatus 1404.

[0152] As discussed supra, the PRACH power variation component 198 may be configured to obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and transmit, to a network node, the plurality of random access message transmissions using the power variation pattern. The PRACH power variation component 198 may be within the cellular baseband processor(s) 1424, the application processor(s) 1406, or both the cellular baseband processor(s) 1424 and the application processor(s) 1406. The PRACH power variation component 198 may be one or more hardware components specifically configured to carry out the stated processes / algorithm, implemented by one or more processors configured to perform the stated processes / algorithm, stored within a computer-readable medium for implementation by one or more processors, or some combination thereof. When multiple processors are implemented, the multiple processors may perform the stated processes / algorithm individually or in combination. As shown, the apparatus 1404 may include a variety of components configured for various functions. In one configuration, the apparatus 1404, and in particular the cellular baseband processor(s) 1424 and / or the application processor(s) 1406, may include means for obtaining a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions. The apparatus 1404, and in particular the cellular baseband processor(s) 1424 and / or the application processor(s) 1406, may include means for transmitting, to a network node, the plurality of random access message transmissions using the power variation pattern. The apparatus 1404, and in particular the cellular129025-2544WO01Qualcomm Ref. No. 2407699WO 61 / 79 baseband processor(s) 1424 and / or the application processor(s) 1406, may include means for receiving the random access message configuration via radio resource control (RRC) signaling. The apparatus 1404, and in particular the cellular baseband processor(s) 1424 and / or the application processor(s) 1406, may include means for receiving at least one second random access message (Msg 2) based on at least one Msg 1 transmission in the plurality of Msg 1 transmissions. The apparatus 1404, and in particular the cellular baseband processor(s) 1424 and / or the application processor(s) 1406, may include means for selecting, from a resource allocation indicated in one of the multiple second random access messages, a resource for transmitting a third random access message (Msg 3). The apparatus 1404, and in particular the cellular baseband processor(s) 1424 and / or the application processor(s) 1406, may include means for transmitting, via the selected resource, the Msg 3. The apparatus 1404, and in particular the cellular baseband processor(s) 1424 and / or the application processor(s) 1406, may include means for identifying, in the multiple second random access messages, a common timing advance value and a set of transmission power control values that are consistent with the power variation pattern. The apparatus 1404 may further include means for performing any of the aspects described in connection with the flowcharts in FIGs. 10 or 11, and / or performed by the UE in the communication flow of FIG. 9. The means may be the PRACH power variation component 198 of the apparatus 1404 configured to perform the functions recited by the means. As described supra, the apparatus 1404 may include the TX processor 368, the RX processor 356, and the controller / processor 359. As such, in one configuration, the means may be the TX processor 368, the RX processor 356, and / or the controller / processor 359 configured to perform the functions recited by the means.

[0153] FIG. 15 is a diagram 1500 illustrating an example of a hardware implementation for a network entity 1502. The network entity 1502 may be a BS, a component of a BS, or may implement BS functionality. The network entity 1502 may include at least one of a CU 1510, a DU 1530, or an RU 1540. For example, depending on the layer functionality handled by the PRACH power variation component 199, the network entity 1502 may include the CU 1510; both the CU 1510 and the DU 1530; each of the CU 1510, the DU 1530, and the RU 1540; the DU 1530; both the DU 1530 and the RU 1540; or the RU 1540. The CU 1510 may include at least one CU processor129025-2544WO01Qualcomm Ref. No. 2407699WO 62 / 791512. The CU processor(s) 1512 may include on-chip memory 1512'. In some aspects, the CU 1510 may further include additional memory modules 1514 and a communications interface 1518. The CU 1510 communicates with the DU 1530 through a midhaul link, such as an Fl interface. The DU 1530 may include at least one DU processor 1532. The DU processor(s) 1532 may include on-chip memory 1532'. In some aspects, the DU 1530 may further include additional memory modules 1534 and a communications interface 1538. The DU 1530 communicates with the RU 1540 through a fronthaul link. The RU 1540 may include at least one RU processor 1542. The RU processor(s) 1542 may include on-chip memory 1542'. In some aspects, the RU 1540 may further include additional memory modules 1544, one or more transceivers 1546, one or more antennas 1580, and a communications interface 1548. The RU 1540 communicates with the UE 104. The on-chip memory 1512', 1532', 1542' and the additional memory modules 1514, 1534, 1544 may each be considered a computer-readable medium / memory. Each computer-readable medium / memory may be non-transitory. Each of the processors 1512, 1532, 1542 is responsible for general processing, including the execution of software stored on the computer- readable medium / memory. The software, when executed by the corresponding processor(s) causes the processor(s) to perform the various functions described supra. The computer-readable medium / memory may also be used for storing data that is manipulated by the processor(s) when executing software.

[0154] As discussed supra, the PRACH power variation component 199 may be configured to transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and receive, from a UE, the plurality of random access message transmissions using the power variation pattern. The PRACH power variation component 199 may be within one or more processors of one or more of the CU 1510, DU 1530, and the RU 1540. The PRACH power variation component 199 may be one or more hardware components specifically configured to carry out the stated processes / algorithm, implemented by one or more processors configured to perform the stated processes / algorithm, stored within a computer-readable medium for implementation by one or more processors, or some combination thereof. When multiple processors are implemented, the multiple processors may perform the stated processes / algorithm individually or in combination. The network entity 1502 may include a variety of components129025-2544WO01Qualcomm Ref. No. 2407699WO 63 / 79 configured for various functions. In one configuration, the network entity 1502 may include means for transmitting a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions. The network entity 1502, in some aspects, may include means for receiving, from a user equipment (UE), the plurality of random access message transmissions using the power variation pattern. The network entity 1502, in some aspects, may include means for transmitting the random access message configuration via radio resource control (RRC) signaling. The network entity 1502, in some aspects, may include means for transmitting at least one second random access message (Msg 2) based on a first Msg 1 transmission in the plurality of Msg 1 transmissions. The network entity 1502, in some aspects, may include means for identifying the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1 transmissions and a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern. The network entity 1502, in some aspects, may include means for transmitting multiple second random access messages in response to the plurality of Msg 1 transmissions. The network entity 1502, in some aspects, may include means for receiving, from at least one additional UE, an additional plurality of Msg 1 transmissions using an additional power variation pattern. The network entity 1502, in some aspects, may include means for omitting, based on the association with the same preamble and the same random access occasion, a transmission of a second Msg 2 for the at least one Msg 1 transmission and the at least one additional Msg 1. The network entity 1502 may further include means for performing any of the aspects described in connection with the flowchart in FIGs. 12 and 13, and / or performed by the base station in the communication flow of FIG. 9. The means may be the PRACH power variation component 199 of the network entity 1502 configured to perform the functions recited by the means. As described supra, the network entity 1502 may include the TX processor 316, the RX processor 370, and the controller / processor 375. As such, in one configuration, the means may be the TX processor 316, the RX processor 370, and / or the controller / processor 375 configured to perform the functions recited by the means.

[0155] Various aspects relate generally to using transmit power variations at a UE between the multiple transmitted preambles to improve the msg3 resource allocation and129025-2544WO01Qualcomm Ref. No. 2407699WO 64 / 79 collision detection. Some aspects more specifically relate to adding a power-domain signature to multiple RACH / PRACH / Msg 1 transmissions (e.g., the multiple first random access transmissions based on the multiple randomly selected preamble sequences as discussed above). In some aspects, the use of the transmit power variations (e.g., an additional power-domain signature applied to multiple PRACH transmissions) may allow the base station to identify which detected preambles over multiple ROs are associated with the same UE based on the power pattern and detected delays. The base station may allocate a single set of resources for a third random access message (e.g., a “Msg 3”) and send a single Msg 2 for the multiple first random access transmissions. From the UE’s perspective, if multiple “Msg 2”s are received, it can identify which “Msg 2”s correspond to its own PRACH transmissions based on the power variation pattern (i.e., TPC) and combine them to improve TA and TPC accuracy. In some examples, a UE may be configured to obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and transmit, to a network node, the plurality of random access message transmissions using the power variation pattern. In some aspects, a network device may be configured to transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions and receive, from a UE, the plurality of random access message transmissions using the power variation pattern.

[0156] Particular aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. In some examples, by introducing transmit power variations at a UE between the multiple transmitted preambles, the described techniques can be used to improve resource allocation for Msg 3 and reduce collisions between random access messages transmitted by different UEs.

[0157] It is understood that the specific order or hierarchy of blocks in the processes / flowcharts disclosed is an illustration of example approaches. Based upon design preferences, it is understood that the specific order or hierarchy of blocks in the processes / flowcharts may be rearranged. Further, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not limited to the specific order or hierarchy presented.129025-2544WO01Qualcomm Ref. No. 2407699WO 65 / 79

[0158] The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. 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. Thus, the claims are not limited to the aspects described herein, but are to be accorded the full scope consistent with the language claims. Reference to an element in the singular does not mean “one and only one” unless specifically so stated, but rather “one or more.” Terms such as “if,” “when,” and “while” do not imply an immediate temporal relationship or reaction. That is, these phrases, e.g., “when,” do not imply an immediate action in response to or during the occurrence of an action, but simply imply that if a condition is met then an action will occur, but without requiring a specific or immediate time constraint for the action to occur. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C,” “one or more of A, B, or C,” “at least one of A, B, and C,” “one or more of A, B, and C,” and “A, B, C, or any combination thereof’ include any combination of A, B, and / or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C,” “one or more of A, B, or C,” “at least one of A, B, and C,” “one or more of A, B, and C,” and “A, B, C, or any combination thereof’ may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. Sets should be interpreted as a set of elements where the elements number one or more. Accordingly, for a set of X, X would include one or more elements. When at least one processor (i.e., a set of one or more processors P) is configured to perform a set of functions F, each processor of P may be configured to perform a subset S of F, where S £ F. Accordingly, each processor of the at least one processor may be configured to perform a particular subset of the set of functions, where the subset is the full set, a proper subset of the set, or an empty subset of the set. A processor may be referred to as processor circuitry. A memory / memory module may be referred to as memory circuitry. If a first apparatus receives data from or transmits data to a second apparatus, the data may be received / transmitted directly between the first and second129025-2544WO01Qualcomm Ref. No. 2407699WO 66 / 79 apparatuses, or indirectly between the first and second apparatuses through a set of apparatuses. A device configured to “output” data or “provide” data, such as a transmission, signal, or message, may transmit the data, for example with a transceiver, or may send the data to a device that transmits the data. A device configured to “obtain” data, such as a transmission, signal, or message, may receive, for example with a transceiver, or may obtain the data from a device that receives the data. Information stored in a memory includes instructions and / or data. 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 encompassed by the claims. Moreover, nothing disclosed herein is dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module,” “mechanism,” “element,” “device,” and the like may not be a substitute for the word “means.” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for.”

[0159] As used herein, the phrase “based on” shall not be construed as a reference to a closed set of information, one or more conditions, one or more factors, or the like. In other words, the phrase “based on A” (where “A” may be information, a condition, a factor, or the like) shall be construed as “based at least on A” unless specifically recited differently.

[0160] The following aspects are illustrative only and may be combined with other aspects or teachings described herein, without limitation.

[0161] Aspect 1 is a method of wireless communication at a user equipment (UE), comprising: obtaining a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions; and transmitting, to a network node, the plurality of random access message transmissions using the power variation pattern.

[0162] Aspect 2 is the method of aspect 1, wherein the power variation pattern is a first power variation pattern of a plurality of power variation patterns, wherein the random access message configuration indicates the plurality of power variation patterns, wherein each power variation pattern of the plurality of power variation patterns is associated with a set of preamble sequences, and wherein using the first power variation pattern for the plurality of random access message transmissions is based at least in part on129025-2544WO01Qualcomm Ref. No. 2407699WO 67 / 79 an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions.

[0163] Aspect 3 is the method of any of aspects 1 and 2, wherein obtaining the random access message configuration comprises receiving the random access message configuration via radio resource control (RRC) signaling.

[0164] Aspect 4 is the method of any of aspects 1 to 3, wherein the plurality of random access message transmissions is a plurality of first random access message (Msg 1) transmissions, the method further comprising: receiving at least one second random access message (Msg 2) based on at least one Msg 1 transmission in the plurality of Msg 1 transmissions.

[0165] Aspect 5 is the method of aspect 4, wherein receiving the at least one Msg 2 comprises receiving multiple second random access messages, the method further comprising: selecting, from a resource allocation indicated in one of the multiple second random access messages, a resource for transmitting a third random access message (Msg 3); and transmitting, via the selected resource, the Msg 3.

[0166] Aspect 6 is the method of aspect 5, wherein at least one received Msg 2 of the multiple second random access messages comprises: a first timing advance value for a first received Msg 1 ; a second timing advance value for a second received Msg 1 ; a first transmission power control value for the first received Msg 1; and a second transmission power control value for the second received Msg 1.

[0167] Aspect 7 is the method of aspect 6, wherein the at least one received Msg 2 of the multiple second random access messages further comprises: a first resource allocation for a first Msg 3 associated with the first received Msg 1; and a second resource allocation for a second Msg 3 associated with the second received Msg 1.

[0168] Aspect 8 is the method of any of aspects 6 and 7, wherein selecting, from the resource allocation indicated in one of the multiple second random access messages, the resource for transmitting the Msg 3 comprises: identifying, in the multiple second random access messages, a common timing advance value and a set of transmission power control values that are consistent with the power variation pattern, wherein the resource allocation indicated in the one of the multiple second random access messages is associated with at least the common timing advance value.129025-2544WO01Qualcomm Ref. No. 2407699WO 68 / 79

[0169] Aspect 9 is a method of wireless communication at a network node, comprising: transmitting a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions; and receiving, from a user equipment (UE), the plurality of random access message transmissions using the power variation pattern.

[0170] Aspect 10 is the method of aspect 9, wherein the power variation pattern is a first power variation pattern of a plurality of power variation patterns, wherein the random access message configuration indicates the plurality of power variation patterns, wherein each power variation pattern of the plurality of power variation patterns is associated with a set of preamble sequences, and wherein the first power variation pattern for the plurality of random access message transmissions is based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions.

[0171] Aspect 11 is the method of any of aspects 9 and 10, wherein transmitting the random access message configuration comprises transmitting the random access message configuration via radio resource control (RRC) signaling.

[0172] Aspect 12 is the method of any of aspects 9 to 11, wherein the plurality of random access message transmissions is a plurality of first random access message (Msg 1) transmissions, the method further comprising: transmitting at least one second random access message (Msg 2) based on a first Msg 1 transmission in the plurality of Msg 1 transmissions.

[0173] Aspect 13 is the method of aspect 12, further comprising: identifying the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1 transmissions and a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern, wherein the at least one Msg 2 is a single Msg 2 transmitted in response to the plurality of Msg 1 transmissions.

[0174] Aspect 14 is the method of aspect 12 and 13, wherein transmitting the at least one Msg 2 comprises transmitting multiple second random access messages in response to the plurality of Msg 1 transmissions.

[0175] Aspect 15 is the method of aspect 14, further comprising: receiving, from at least one additional UE, an additional plurality of Msg 1 transmissions using an additional129025-2544WO01Qualcomm Ref. No. 2407699WO 69 / 79 power variation pattern, wherein at least one Msg 1 transmission in the plurality of Msg 1 transmissions is associated with a same preamble and a same random access occasion as at least one additional Msg 1 transmission of the additional plurality of Msg 1 transmissions.

[0176] Aspect 16 is the method of aspect 15, wherein at least one transmitted Msg 2 of the multiple second random access messages is associated with the at least one Msg 1 transmission and comprises: a first timing advance value for the at least one Msg 1 transmission; a second timing advance value for the at least one additional Msg 1 transmission; a first transmission power control value for the at least one Msg 1 transmission; and a second transmission power control value for the at least one additional Msg 1 transmission.

[0177] Aspect 17 is the method of aspect 16, wherein the at least one transmitted Msg 2 of the multiple second random access messages further comprises: a first resource allocation for a first Msg 3 associated with the at least one Msg 1 transmission; and a second resource allocation for a second Msg 3 associated with the at least one additional Msg 1 transmission.

[0178] Aspect 18 is the method of aspect 15, further comprising: omitting, based on the association with the same preamble and the same random access occasion, a transmission of a second Msg 2 for the at least one Msg 1 transmission and the at least one additional Msg 1.

[0179] Aspect 19 is an apparatus for wireless communication at a user equipment, comprising: at least one memory; and at least one processor coupled to the at least one memory, the at least one processor is configured to perform the method of any of aspects 1 to 8.

[0180] Aspect 20 is an apparatus for wireless communication at a UE, comprising means for performing each step in the method of any of aspects 1 to 8.

[0181] Aspect 21 is the apparatus of any of aspects 19 to 21, further comprising a transceiver configured to receive or to transmit in association with the method of any of aspects 1 to 8.

[0182] Aspect 22 is a computer-readable medium storing computer executable code at a UE, the code when executed by at least one processor causes the at least one processor to perform the method of any of aspects 1 to 8.129025-2544WO01Qualcomm Ref. No. 2407699WO 70 / 79

[0183] Aspect 23 is an apparatus for wireless communication at a network node, comprising: at least one memory; and at least one processor coupled to the at least one memory, the at least one processor is configured to perform the method of any of aspects 9 to 18.

[0184] Aspect 24 is an apparatus for wireless communication at a network node, comprising means for performing each step in the method of any of aspects 9 to 18.

[0185] Aspect 25 is the apparatus of any of aspects 23 to 24, further comprising a transceiver configured to receive or to transmit in association with the method of any of aspects 9 to 18.

[0186] Aspect 26 is a computer-readable medium storing computer executable code communication at a network node, the code when executed by at least one processor causes the at least one processor to perform the method of any of aspects 9 to 18.129025-2544WO01

Claims

Qualcomm Ref. No. 2407699WO 71 / 79CLAIMSWHAT IS CLAIMED IS:

1. An apparatus for wireless communication at a user equipment (UE), comprising: at least one memory; and at least one processor coupled to the at least one memory and, based at least in part on information stored in the at least one memory, the at least one processor is configured to: obtain a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions; and transmit, to a network node, the plurality of random access message transmissions using the power variation pattern.

2. The apparatus of claim 1, wherein the power variation pattern is a first power variation pattern of a plurality of power variation patterns, wherein the random access message configuration indicates the plurality of power variation patterns, wherein each power variation pattern of the plurality of power variation patterns is associated with a set of preamble sequences, and wherein using the first power variation pattern for the plurality of random access message transmissions is based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions.

3. The apparatus of claim 1, further comprising a transceiver coupled to the at least one processor, wherein to obtain the random access message configuration the at least one processor, individually or in any combination, is further configured to: receive, via the transceiver, the random access message configuration via radio resource control (RRC) signaling.

4. The apparatus of claim 1, wherein the plurality of random access message transmissions is a plurality of first random access message (Msg 1) transmissions, and wherein the at least one processor, individually or in any combination, is further configured to:129025-2544WO01Qualcomm Ref. No. 2407699WO 72 / 79 receive at least one second random access message (Msg 2) based on at least one Msg 1 transmission in the plurality of Msg 1 transmissions.

5. The apparatus of claim 4, wherein to receive the at least one Msg 2, the at least one processor, individually or in any combination, is configured to receive multiple second random access messages, and wherein the at least one processor, individually or in any combination, is further configured to: select, from a resource allocation indicated in one of the multiple second random access messages, a resource for transmitting a third random access message (Msg 3); and transmit, via the selected resource, the Msg 3.

6. The apparatus of claim 5, wherein at least one received Msg 2 of the multiple second random access messages comprises: a first timing advance value for a first received Msg 1 ; a second timing advance value for a second received Msg 1 ; a first transmission power control value for the first received Msg 1; and a second transmission power control value for the second received Msg 1.

7. The apparatus of claim 6, wherein the at least one received Msg 2 of the multiple second random access messages further comprises: a first resource allocation for a first Msg 3 associated with the first received Msg 1; and a second resource allocation for a second Msg 3 associated with the second received Msg 1.

8. The apparatus of claim 6, wherein to select, from the resource allocation indicated in one of the multiple second random access messages, the resource for transmitting the Msg 3, the at least one processor, individually or in any combination, is configured to: identify, in the multiple second random access messages, a common timing advance value and a set of transmission power control values that are consistent with the power variation pattern, wherein the resource allocation indicated in the one of the129025-2544WO01Qualcomm Ref. No. 2407699WO 73 / 79 multiple second random access messages is associated with at least the common timing advance value.

9. An apparatus for wireless communication at a network node, comprising: at least one memory; and at least one processor coupled to the at least one memory and, based at least in part on information stored in the at least one memory, the at least one processor is configured to: transmit a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions; and receive, from a user equipment (UE), the plurality of random access message transmissions using the power variation pattern.

10. The apparatus of claim 9, wherein the power variation pattern is a first power variation pattern of a plurality of power variation patterns, wherein the random access message configuration indicates the plurality of power variation patterns, wherein each power variation pattern of the plurality of power variation patterns is associated with a set of preamble sequences, and wherein the first power variation pattern for the plurality of random access message transmissions is based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions.

11. The apparatus of claim 9, further comprising a transceiver coupled to the at least one processor wherein to transmit the random access message configuration the at least one processor, individually or in any combination, is configured to transmit, via the transceiver, the random access message configuration via radio resource control (RRC) signaling.

12. The apparatus of claim 9, wherein the plurality of random access message transmissions is a plurality of first random access message (Msg 1) transmissions, and wherein the at least one processor, individually or in any combination, is further configured to:129025-2544WO01Qualcomm Ref. No. 2407699WO 74 / 79 transmit at least one second random access message (Msg 2) based on a first Msg 1 transmission in the plurality of Msg 1 transmissions.

13. The apparatus of claim 12, wherein the at least one processor, individually or in any combination, is further configured to: identify the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1 transmissions and a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern, wherein the at least one Msg 2 is a single Msg 2 in response to the plurality of Msg 1 transmissions.

14. The apparatus of claim 12, wherein to transmit the at least one Msg 2, the at least one processor, individually or in any combination, is configured to transmit multiple second random access messages in response to the plurality of Msg 1 transmissions.

15. The apparatus of claim 14, wherein the at least one processor, individually or in any combination, is further configured to: receive, from at least one additional UE, an additional plurality of Msg 1 transmissions using an additional power variation pattern, wherein at least one Msg 1 transmission in the plurality of Msg 1 transmissions is associated with a same preamble and a same random access occasion as at least one additional Msg 1 transmission of the additional plurality of Msg 1 transmissions.

16. The apparatus of claim 15, wherein at least one transmitted Msg 2 of the multiple second random access messages is associated with the at least one Msg 1 transmission and comprises: a first timing advance value for the at least one Msg 1 transmission; a second timing advance value for the at least one additional Msg 1 transmission; a first transmission power control value for the at least one Msg 1 transmission; and129025-2544WO01Qualcomm Ref. No. 2407699WO 75 / 79 a second transmission power control value for the at least one additional Msg 1 transmission.

17. The apparatus of claim 16, wherein the at least one transmitted Msg 2 of the multiple second random access messages further comprises: a first resource allocation for a first Msg 3 associated with the at least one Msg 1 transmission; and a second resource allocation for a second Msg 3 associated with the at least one additional Msg 1 transmission.

18. The apparatus of claim 15, wherein the at least one processor, individually or in any combination, is further configured to: omit, based on the association with the same preamble and the same random access occasion, a transmission of a second Msg 2 for the at least one Msg 1 transmission and the at least one additional Msg 1.

19. A method of wireless communication at a user equipment (UE), comprising: obtaining a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions; and transmitting, to a network node, the plurality of random access message transmissions using the power variation pattern.

20. The method of claim 19, wherein the power variation pattern is a first power variation pattern of a plurality of power variation patterns, wherein the random access message configuration indicates the plurality of power variation patterns, wherein each power variation pattern of the plurality of power variation patterns is associated with a set of preamble sequences, and wherein using the first power variation pattern for the plurality of random access message transmissions is based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions.129025-2544WO01Qualcomm Ref. No. 2407699WO 76 / 7921. The method of claim 19, wherein the plurality of random access message transmissions is a plurality of first random access message (Msg 1) transmissions, the method further comprising: receiving multiple second random access messages (Msg 2s) based on multiple Msg 1 transmission in the plurality of Msg 1 transmissions; selecting, from a resource allocation indicated in one of the multiple second random access messages, a resource for transmitting a third random access message (Msg 3); and transmitting, via the selected resource, the Msg 3.

22. The method of claim 21, wherein at least one received Msg 2 of the multiple second random access messages comprises: a first timing advance value for a first received Msg 1 ; a second timing advance value for a second received Msg 1 ; a first transmission power control value for the first received Msg 1; and a second transmission power control value for the second received Msg 1.

23. The method of claim 22, wherein the at least one received Msg 2 of the multiple second random access messages further comprises: a first resource allocation for a first Msg 3 associated with the first received Msg 1; and a second resource allocation for a second Msg 3 associated with the second received Msg 1.

24. The method of claim 22, wherein selecting, from the resource allocation indicated in one of the multiple second random access messages, the resource for transmitting the Msg 3 comprises: identifying, in the multiple second random access messages, a common timing advance value and a set of transmission power control values that are consistent with the power variation pattern, wherein the resource allocation indicated in the one of the129025-2544WO01Qualcomm Ref. No. 2407699WO 77 / 79 multiple second random access messages is associated with at least the common timing advance value.

25. A method of wireless communication at a network node, comprising: transmitting a random access message configuration indicating a power variation pattern for a plurality of random access message transmissions; and receiving, from a user equipment (UE), the plurality of random access message transmissions using the power variation pattern.

26. The method of claim 25, wherein the power variation pattern is a first power variation pattern of a plurality of power variation patterns, wherein the random access message configuration indicates the plurality of power variation patterns, wherein each power variation pattern of the plurality of power variation patterns is associated with a set of preamble sequences, and wherein the first power variation pattern for the plurality of random access message transmissions is based at least in part on an association between the first power variation pattern and a first preamble sequence associated with a first random access message in the plurality of random access message transmissions.

27. The method of claim 25, wherein the plurality of random access message transmissions is a plurality of first random access message (Msg 1) transmissions, the method further comprising: transmitting at least one second random access message (Msg 2) based on a first Msg 1 transmission in the plurality of Msg 1 transmissions.

28. The method of claim 27, further comprising: identifying the plurality of Msg 1 transmissions as being related based on a timing advance value associated with each Msg 1 transmission of the plurality of Msg 1 transmissions and a received power associated with each Msg 1 transmission of the plurality of Msg 1 transmissions that is consistent with the power variation pattern, wherein the at least one Msg 2 is a single Msg 2 transmitted in response to the plurality of Msg 1 transmissions.129025-2544WO01Qualcomm Ref. No. 2407699WO 78 / 7929. The method of claim 27, wherein transmitting the at least one Msg 2 comprises transmitting multiple second random access messages in response to the plurality of Msg 1 transmissions, the method further comprising: receiving, from at least one additional UE, an additional plurality of Msg 1 transmissions using an additional power variation pattern, wherein at least one Msg 1 transmission in the plurality of Msg 1 transmissions is associated with a same preamble and a same random access occasion as at least one additional Msg 1 transmission of the additional plurality of Msg 1 transmissions.

30. The method of claim 29, wherein at least one transmitted Msg 2 of the multiple second random access messages is associated with the at least one Msg 1 transmission and comprises: a first timing advance value for the at least one Msg 1 transmission; a second timing advance value for the at least one additional Msg 1 transmission; a first transmission power control value for the at least one Msg 1 transmission; a second transmission power control value for the at least one additional Msg 1 transmission; a first resource allocation for a first Msg 3 associated with the at least one Msg 1 transmission; and a second resource allocation for a second Msg 3 associated with the at least one additional Msg 1 transmission.129025-2544WO01

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