WO2021109101A1

WO2021109101A1 - Pusch opportunity repetitions for rach procedure

Info

Publication number: WO2021109101A1
Application number: PCT/CN2019/123509
Authority: WO
Inventors: Qiaoyu Li; Jing LEI; Chao Wei; Wanshi Chen; Hao Xu; Yu Zhang; Peter Pui Lok ANG; Krishna Kiran Mukkavilli
Original assignee: Qualcomm Incorporated
Priority date: 2019-12-06
Filing date: 2019-12-06
Publication date: 2021-06-10

Abstract

In an aspect, a UE identifies a set of RACH opportunities over which to transmit a preamble (e.g., a Msg-A preamble of a 2-Step PRACH procedure). The UE selects a preamble sequence group associated with a repetition level for an uplink message (e.g., a Msg-A payload of a 2-Step PRACH procedure). The UE transmits the preamble to a BS on the identified set of ROs. The BS identifies the repetition level from the preamble. The UE transmits the uplink message to the set of POs in accordance with the repetition level.

Description

PUSCH OPPORTUNITY REPETITIONS FOR RACH PROCEDURE

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

Aspects of the disclosure relate generally to wireless communications and to techniques and apparatuses related to physical uplink shared channel (PUSCH) opportunity (PO) repetitions for a random access channel (RACH) procedure.

2. Description of the Related Art

Wireless communication systems have developed through various generations, including a first-generation analog wireless phone service (1G) , a second-generation (2G) digital wireless phone service (including interim 2.5G networks) , a third-generation (3G) high speed data, Internet-capable wireless service, and a fourth-generation (4G) service (e.g., Long-Term Evolution (LTE) , WiMax) . There are presently many different types of wireless communication systems in use, including cellular and personal communications service (PCS) systems. Examples of known cellular systems include the cellular Analog Advanced Mobile Phone System (AMPS) , and digital cellular systems based on code division multiple access (CDMA) , frequency division multiple access (FDMA) , time division multiple access (TDMA) , the Global System for Mobile access (GSM) variation of TDMA, etc.

A fifth generation (5G) mobile standard calls for higher data transfer speeds, greater numbers of connections, and better coverage, among other improvements. The 5G standard (also referred to as “New Radio” or “NR” ) , according to the Next Generation Mobile Networks Alliance, is designed to provide data rates of several tens of megabits per second to each of tens of thousands of users, with 1 gigabit per second to tens of workers on an office floor. Several hundreds of thousands of simultaneous connections should be supported in order to support large sensor deployments. Consequently, the spectral efficiency of 5G mobile communications should be significantly enhanced compared to the current 4G /LTE standard. Furthermore, signaling efficiencies should be enhanced and latency should be substantially reduced compared to current standards.

SUMMARY

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, and is intended to neither identify key or critical elements of all aspects nor delineate 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.

Starting in 3GPP Rel. 17, a number of these UE types are being allocated a new UE classification denoted as ‘NR-Light’ . Examples of UE types that fall under the NR-Light classification include wearable devices (e.g., smart watches, etc. ) , industrial sensors, video cameras (e.g., surveillance cameras, etc. ) , and so on. Generally, the UE types grouped under the NR-Light classification are associated with lower communicative capacity. For example, relative to ‘normal’ UEs (e.g., UEs not classified as NR-Light) , NR-Light UEs may be limited in terms of maximum bandwidth (e.g., 5 MHz, 10 MHz, 20 MHz, etc. ) , maximum transmission power (e.g., 20 dBm, 14 dBm, etc. ) , number of receive antennas (e.g., 1 receive antenna, 2 receive antennas, etc. ) , and so on. Some NR-Light UEs may also be sensitive in terms of power consumption (e.g., requiring a long battery life, such as several years) and may be highly mobile. Moreover, in some designs, it is generally desirable for NR-Light UEs to co-exist with UEs implementing protocols such as eMBB, URLLC, LTE NB-IoT/MTC, and so on.

Embodiments of the disclosure are directed associating a plurality of preamble sequence groups with a set of ROs, whereby each respective preamble sequence group is associated with a different repetition level for an uplink message (e.g., Msg-A payload or PUSCH) . In some designs, once a desired repetition level for the uplink message is determined, a preamble (e.g., Msg-A preamble) preceding the uplink message (e.g., Msg-A payload or PUSCH) can be transmitted to the base station in a manner that indicates the uplink message’s repetition level. In some designs, the various embodiments described below are implemented with respect to UEs that belong to a particular UE class (e.g., power-constrained UEs such as NR-Light UEs) . As used herein, a “set” of ROs refers to a grouping of one or more ROs.

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a UE. The UE may identify a set of random access channel (RACH) opportunities (ROs) over which to transmit a preamble associated with a RACH procedure. The UE may further select a first preamble sequence group from among a plurality of preamble sequence groups associated with the identified set of ROs based on a repetition level preference for an uplink message on one or more physical uplink shared channel (PUSCH) opportunities (POs) , wherein each of the plurality of preamble sequence groups is associated with a different repetition level for the uplink message. The UE may further transmit the preamble on the identified set of ROs. The UE may further transmit, before a response to the preamble is received, the uplink message on a first set of POs associated with the selected preamble sequence group, wherein the first set of POs corresponds to a first repetition level associated with the selected preamble sequence group

In another aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a base station. The base station may receive, from a user equipment (UE) , a preamble associated with a random access channel (RACH) procedure over one of a plurality of sets of RACH opportunities (ROs) , wherein the set of ROs over which the preamble is received is associated with one of a plurality of preamble sequence groups, wherein each of the plurality of preamble sequence groups is associated with a different repetition level for an uplink message associated with the RACH procedure on one or more physical uplink shared channel (PUSCH) opportunities (POs) . The base station may further identify a first set of POs for the uplink message based on the preamble sequence group associated with the set of ROs over which the preamble is received, wherein the first set of POs corresponds to the repetition level for the associated preamble sequence group. The base station may further receive, from the UE before a response to the preamble is transmitted, the uplink message on the first set of POs in accordance with the corresponding repetition level.

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

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

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

FIG. 2 is a diagram illustrating an example of a base station in communication with a UE in a wireless communication network.

FIG. 3 illustrates a 4-Step Physical Random Access Channel (PRACH) procedure in accordance with an embodiment of the disclosure.

FIG. 4 illustrates a 2-Step PRACH procedure in accordance with an embodiment of the disclosure.

FIG. 5 illustrates a 2-Step PRACH procedure in accordance with another embodiment of the disclosure.

FIG. 6 illustrates an example of a Msg-A mapping scheme in accordance with an embodiment of the disclosure.

FIG. 7A illustrates examples of preamble transmission schemes that are characterized as long preambles in accordance with an embodiment of the disclosure.

FIG. 7B illustrates examples of preamble transmission schemes that are characterized as short preambles in accordance with an embodiment of the disclosure.

FIG. 7C illustrates examples of NR PRACH time domain configurations 700C in accordance with an embodiment of the disclosure.

FIG. 8 illustrates an exemplary process of wireless communications according to an aspect of the disclosure.

FIG. 9 illustrates an exemplary process of wireless communications according to an aspect of the disclosure.

FIG. 10A illustrates an RO-PO configuration 1000A comprising various sets of POs that are each associated with different repetition levels for a Msg-A payload in accordance with an embodiment of the disclosure.

FIG. 10B illustrates an RO-PO configuration comprising various sets of POs that are each associated with different repetition levels for a Msg-A payload in accordance with an embodiment of the disclosure.

FIG. 11 illustrates an example implementation of the processes of FIGS. 8-9 in accordance with an embodiment of the disclosure.

FIG. 12 is a conceptual data flow diagram illustrating the data flow between different means/components in exemplary apparatuses in accordance with an embodiment of the disclosure.

FIG. 13 is a diagram illustrating an example of a hardware implementation for an apparatus employing a processing system.

FIG. 14 is a diagram illustrating another example of a hardware implementation for an apparatus employing a processing system.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purposes of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that 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.

Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, and/or the like (collectively referred to as “elements” ) . These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

By way of example, an element, or any portion of an element, or any combination of elements may be implemented with a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, digital signal processors (DSPs) , 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 shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and/or the like, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

Accordingly, in one or more example embodiments, the functions described may be implemented in hardware, software, firmware, 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, and not limitation, such computer-readable media can comprise a random-access memory (RAM) , a read-only memory (ROM) , an electrically erasable programmable ROM (EEPROM) , compact disk ROM (CD-ROM) or other optical disk storage, magnetic disk storage or other magnetic storage devices, combinations of the aforementioned 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.

It should be noted that while aspects may be described herein using terminology commonly associated with 3G and/or 4G wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as 5G and later, including 5G technologies.

FIG. 1 is a diagram illustrating a wireless network 100 in which aspects of the present disclosure may be practiced. The wireless network 100 may be an LTE network or some other wireless network, such as a 5G network. The wireless network 100 may include a number of BSs 110 (shown as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities. A BS is an entity that communicates with user equipment (UEs) and may also be referred to as a base station, a 5G BS, a Node B, a gNB, a 5G NB, an access point, a transmit receive point (TRP) , and/or the like. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS and/or a BS subsystem serving this coverage area, depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG) ) . A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in FIG. 1, a BS 110a may be a macro BS for a macro cell 102a, a BS 110b may be a pico BS for a pico cell 102b, and a BS 110c may be a femto BS for a femto cell 102c. A BS may support one or multiple (e.g., three) cells. The terms “eNB” , “base station” , “5G BS” , “gNB” , “TRP” , “AP” , “node B” , “5G NB” , and “cell” may be used interchangeably herein.

In some examples, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some examples, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces such as a direct physical connection, a virtual network, and/or the like using any suitable transport network.

Wireless network 100 may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS) . A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in FIG. 1, a relay station 110d may communicate with macro BS 110a and a UE 120d in order to facilitate communication between BS 110a and UE 120d. A relay station may also be referred to as a relay BS, a relay base station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network 100. For example, macro BSs may have a high transmit power level (e.g., 5 to 40 Watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 Watts) .

A network controller 130 may couple to a set of BSs and may provide coordination and control for these BSs. Network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with one another, e.g., directly or indirectly via a wireless or wireline backhaul.

UEs 120 (e.g., 120a, 120b, 120c) may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, etc. A UE may be a cellular phone (e.g., a smart phone) , a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet) ) , an entertainment device (e.g., a music or video device, or a satellite radio) , a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. “MTC” may refer to MTC or eMTC. MTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., that may communicate with a base station, another device (e.g., remote device) , or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, and/or may be implemented as NB-IoT (narrowband internet of things) devices. IoT UEs, eMTC UEs, coverage enhancement (CE) mode UEs, bandwidth-limited (BL) UEs, and other types of UEs that operate using diminished power consumption relative to a baseline UE may be referred to herein as cellular IoT (cIoT) UEs. Some UEs may be considered a Customer Premises Equipment (CPE) . UE 120 may be included inside a housing that houses components of UE 120, such as processor components, memory components, and/or the like.

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, and/or the like. A frequency may also be referred to as a carrier, a frequency channel, and/or the like. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, 5G RAT networks may be deployed.

In some examples, access to the air interface may be scheduled, wherein a scheduling entity (e.g., a base station) allocates resources for communication among some or all devices and equipment within the scheduling entity’s service area or cell. Within the present disclosure, as discussed further below, the scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communication, subordinate entities utilize resources allocated by the scheduling entity. Access to the air interface may be controlled, for example, using a unified access control (UAC) system in which UEs are associated with an access identity (e.g., an access class and/or the like) , which may aim to ensure that certain high-priority UEs (e.g., emergency response UEs, mission critical UEs, and/or the like) can access the air interface even in congested conditions. Updates to the UAC parameters (e.g., priority levels associated with access identities, which access identities are permitted to access the air interface, and/or the like) may be provided for cIoT UEs using a message, such as a paging message or a direct indication information, which may conserve battery power of cIoT UEs.

Base stations are not the only entities that may function as a scheduling entity. That is, in some examples, a UE may function as a scheduling entity, scheduling resources for one or more subordinate entities (e.g., one or more other UEs) . In this example, the UE is functioning as a scheduling entity, and other UEs utilize resources scheduled by the UE for wireless communication. A UE may function as a scheduling entity in a peer-to-peer (P2P) network, and/or in a mesh network. In a mesh network example, UEs may optionally communicate directly with one another in addition to communicating with the scheduling entity.

Thus, in a wireless communication network with a scheduled access to time–frequency resources and having a cellular configuration, a P2P configuration, and a mesh configuration, a scheduling entity and one or more subordinate entities may communicate utilizing the scheduled resources.

As indicated above, FIG. 1 is provided merely as an example. Other examples may differ from what is described with regard to FIG. 1.

FIG. 2 shows a block diagram 200 of a design of base station 110 and UE 120, which may be one of the base stations and one of the UEs in FIG. 1. Base station 110 may be equipped with T antennas 234a through 234t, and UE 120 may be equipped with R antennas 252a through 252r, where in general T ≥ 1 and R ≥ 1.

At base station 110, a transmit processor 220 may receive data from a data source 212 for one or more UEs, may select a modulation and coding scheme (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS selected for the UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI) , and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., the cell-specific reference signal) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (SSS) ) . A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs) 232a through 232t. Each modulator 232 may process a respective output symbol stream (e.g., for orthogonal frequency divisional multiplexing (OFDM) and/or the like) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232a through 232t may be transmitted via T antennas 234a through 234t, respectively. According to various aspects described in more detail below, the synchronization signals can be generated with location encoding to convey additional information.

At UE 120, antennas 252a through 252r may receive the downlink signals from base station 110 and/or other base stations and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM and/or the like) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive (RX) processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller/processor 280. A channel processor may determine reference signal received power (RSRP) , received signal strength indicator (RSSI) , a reference signal received quality (RSRQ) , a channel quality indicator (CQI) , and/or the like.

On the uplink, at UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor 280. Transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, and/or the like) , and transmitted to base station 110. At base station 110, the uplink signals from UE 120 and other UEs may be received by antennas 234, processed by demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120. Receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to controller/processor 240. Base station 110 may include communication unit 244 and communicate to network controller 130 via communication unit 244. Network controller 130 may include communication unit 294, controller/processor 290, and memory 292.

Controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of FIG. 2 may perform one or more techniques associated with UAC parameter updating, as described in more detail elsewhere herein. For example, controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of FIG. 2 may perform or direct operations of various processes as described herein.

Memories

242 and 282 may store data and program codes for BS 110 and UE 120, respectively. A scheduler 246 may schedule UEs for data transmission on the downlink and/or uplink.

As indicated above, FIG. 2 is provided merely as an example. Other examples may differ from what is described with regard to FIG. 2.

As noted above, various device types may be characterized as UEs. Starting in 3GPP Rel. 17, a number of these UE types are being allocated a new UE classification denoted as ‘NR-Light’ . Examples of UE types that fall under the NR-Light classification include wearable devices (e.g., smart watches, etc. ) , industrial sensors, video cameras (e.g., surveillance cameras, etc. ) , and so on. Generally, the UE types grouped under the NR-Light classification are associated with lower communicative capacity. For example, relative to ‘normal’ UEs (e.g., UEs not classified as NR-Light) , NR-Light UEs may be limited in terms of maximum bandwidth (e.g., 5 MHz, 10 MHz, 20 MHz, etc. ) , maximum transmission power (e.g., 20 dBm, 14 dBm, etc. ) , number of receive antennas (e.g., 1 receive antenna, 2 receive antennas, etc. ) , and so on. Some NR-Light UEs may also be sensitive in terms of power consumption (e.g., requiring a long battery life, such as several years) and may be highly mobile. Moreover, in some designs, it is generally desirable for NR-Light UEs to co-exist with UEs implementing protocols such as eMBB, URLLC, LTE NB-IoT/MTC, and so on.

FIG. 3 illustrates a 4-Step Physical Random Access Channel (PRACH) procedure 300 in accordance with an embodiment of the disclosure. The 4-Step PRACH procedure 300 is an initial access procedure by which a UE (e.g., UE 120) can initiate communication with a BS (e.g., BS 110) .

Referring to FIG. 3, at 302, a Message 1 ( “Msg-1” ) of the 4-Step PRACH procedure 300 is transmitted by UE 120 to BS 110. The Msg-1 of 302 may be characterized herein as a PRACH preamble. In an example, the Msg-1 of 302 may be implemented a Zadoff-Chu sequence which indicates the presence of a random access attempt and allows BS 110 to estimate between BS 110 and UE 120.

Referring to FIG. 3, at 304, a Message 2 ( “Msg-2” ) of the 4-Step PRACH procedure 300 is transmitted by BS 110 to UE 120. The Msg-2 of 304 may be characterized herein as a random access response (RAR) . For example, in response to the detected PRACH preamble (or Msg-1) at 302, BS 110 may transmit the Msg-2 of 304 on a downlink (DL) shared channel (SCH) comprising any combination of:

● An index of the detected PRACH preamble (or Msg-1) from 302,

● An uplink timing correction for UE 120,

● A scheduling grant indicating what resource (s) UE 120 should use for transmission of Message 3 ( “Msg-3” ) of the 4-Step PRACH procedure 300, and

● A Temporary Cell Radio Network Temporary Identifier (TC-RNTI) used for further communication between UE 120 and BS 110.

In an example, the Msg-2 of 304 may be scheduled on the SL SCH and indicated on a Physical Downlink Control Channel (PDCCH) using an identity (e.g., a Random Access RNTI (RA-RNTI) which is indicated by the time and frequency resource (s) upon which the PRACH preamble (or Msg-1) from 302 is transmitted.

Referring to FIG. 3, at 306, a Message 3 ( “Msg-3” ) comprising at least a UE identifier (ID) of UE 120 is transmitted by UE 120 to BS 110. In some designs, the Msg-3 is transmitted over Physical Uplink Shared Channel (PUSCH) and may be referred to as a Msg-3 PUSCH. In an example, the Msg-3 transmitted at 306 may be transmitted via the UL SCH resource (s) indicated by the Msg-2 from 304. In some designs, device scrambling is used for the transmission of Msg-3 at 306 (e.g., scrambling based on the TC-RNTI assigned via the Msg-2 from 304) . In some designs, if UE 120 is in a radio resource control (RRC) -Connected state with a C-RNTI already assigned thereto, the C-RNTI may be used as the UE-ID in the Msg-3 at 306. In some designs, if UE 120 is not in a RRC-Connected state, a core network device identifier such as a 40-bit Serving Temporary Mobile Subscriber Identity (S-TMSI) can be used as the UE-ID in the Msg-3 at 306.

Referring to FIG. 3, at 308, another Msg-3 is optionally transmitted as a hybrid automatic repeat request (HARQ) acknowledgment (ACK) to the Msg-2 from 304. In some designs, the Msg-3 is transmitted via PUCCH and may be referred to as a Msg-3 PUCCH. In some designs, whether or not the Msg-3 PUCCH is transmitted at 308 may be configured via RRC signaling or via one or more information elements (IEs) in a system information block (SIB) .

Referring to FIG. 3, at 308, a Message 4 ( “Msg-4” ) of the 4-Step PRACH procedure 300 is transmitted by BS 110 to UE 120. In some designs, the Msg-4 of 308 comprises a downlink message for contention resolution as there is some probability of contention associated with the Msg-3 transmissions at 306-308. For example, if multiple UEs transmit the same Msg-1 (302) at the same time, then the multiple UEs may react to the same Msg-2 (304) such that a collision occurs. In some designs, if UE 120 already has a C-RNTI assigned, contention resolution may be handled by addressing UE 120 on the PDCCH using the C-RNTI. In some designs, if UE 120 does not have a valid C-RNTI (e.g., UE 120 is RRC-Idle prior to 302) , Msg-4 contention resolution may be handled by addressing UE 120 on the PDCCH using the TC-RNTI, with UE 120 comparing (i) the UE-ID received within a PDSCH scheduled by the PDCCH of Msg-4 with (ii) the UE-ID transmitted in the Msg-3 PUSCH at 306, so as to determine the 4-Step PRACH procedure 300 successful if a match is observed, after which the C-RNTI is confirmed as C-RNTI. At 312, UE 120 and BS 110 may optionally exchange user data.

FIG. 4 illustrates a 2-Step PRACH procedure 400 in accordance with an embodiment of the disclosure. Similar to the 4-Step PRACH procedure 300, the 2-Step PRACH procedure 400 is an initial access procedure by which a UE (e.g., UE 120) can initiate communication with a BS (e.g., BS 110) . However, in the 2-Step PRACH procedure 400, the Msg-1 and Msg-3 are transmitted to the BS 110 before any response from the BS 110 is transmitted as ‘Msg-A’ , and the BS 110 sends ‘Msg-b’ (e.g., comprising Msg-2 and Msg-4) back to the UE 120.

Referring to FIG. 4, at 402, UE 120 transmits Msg-A (e.g., a PRACH preamble and associated UE ID information as in Msg-1 and Msg-3) to BS 110. At 404, BS 110 transmits Msg-B (e.g., a RAR along with contention resolution as in Msg-2 and Msg-4) to BS 110. At 406, UE 120 and BS 110 may optionally exchange user data. The processing of the Msg-A and Msg-B is otherwise comparable to the processing of the Msg-1, Msg-2, Msg-3 and Msg-4 in the 4-Step PRACH procedure 300 of FIG. 3.

FIG. 5 illustrates a 2-Step PRACH procedure 500 in accordance with another embodiment of the disclosure. In particular, the 2-Step PRACH procedure 500 is a more detailed implementation of the 2-Step PRACH procedure 400 of FIG. 5.

At 502, BS 110 transmits information to UE 120, including a system synchronization block (SSB) , a system information block (SIB) , and a reference signal (RS) . At 504, UE 120 performs downlink synchronization, system information (SI) decoding and one or more measurements on the transmitted information. At 506, UE 120 transmits a PRACH preamble component of Msg-A to BS 110. At 508, UE 120 transmits a payload component (e.g., comprising UE ID information as in Msg-3) of Msg-A to BS 110. At 510, BS 110 processes the PRACH preamble component of Msg-A. At 512, BS 110 processes the payload component of Msg-A. At 514, BS 110 transmits a RAR via PDCCH, similar to Msg-2. At 516, BS 110 transmits contention resolution information via PDCCH, similar to Msg-4. At 518, UE 120 and BS 110 may optionally exchange user data.

FIG. 6 illustrates an example of a Msg-A mapping scheme 600 in accordance with an embodiment of the disclosure. In FIG. 6, the Msg-A preamble is separated from the Msg-A payload (e.g., DMRS/PUSCH) by a guard time T _G and a transmission gap T _g. The Msg-A preamble maps to one or more ROs and preamble sequence groups (e.g., designated via RO index and associated preamble sequence group index) . The Msg-A payload maps to one or more DMRS resources and PUSCH occasions (POs) (e.g., designated via DMRS resource index and PO index) .

The PRACH preamble (e.g., 302 of FIG. 3, 402 of FIG. 4, 506 of FIG. 5) may be configured in accordance with any of a variety of preamble transmission schemes, which are generally classified as either long preambles or short preambles. In some designs, a total of 13 preamble transmission schemes are defined. FIG. 7A illustrates examples of preamble transmission schemes 700A that are characterized as long preambles in accordance with an embodiment of the disclosure. FIG. 7B illustrates examples of preamble transmission schemes 700B that are characterized as short preambles in accordance with an embodiment of the disclosure. FIG. 7C illustrates examples of NR PRACH time domain configurations 700C in accordance with an embodiment of the disclosure. As shown with respect to FIGS. 7A-7B, the various preamble transmission schemes 700A-700B may differ in terms of various parameters, including by way of example one or more of:

● Preamble format,

● Sequence length (e.g., denoted as “L” in FIGS. 4A-4B) ,

● Numerology or sub-carrier spacing (SCS) ,

● Bandwidth,

● Cycling Prefix (CP) duration,

● Guard Time (GT) duration,

● Total length, and/or

● Number of OFDM symbols.

In a scenario where UE 120 corresponds to a particular class of UE, such as an NR-Light UE, it is possible that the Msg-A preamble of 402 of FIG. 4 or 506 of FIG. 5 is successfully received at BS 110, but the Msg-A payload at 404 of FIG. 4 or 508 of FIG. 5 is not successfully received at BS 110. For example, the Msg-A preamble of 402 of FIG. 4 or 506 of FIG. 5 may be based on relatively long preamble sequences which can be received reliably at BS 110, whereas the Msg-A payload at 404 of FIG. 4 or 508 of FIG. 5 can be based on OFDM signals and may comprise a larger payload than the Msg-A preamble of 402 of FIG. 4 or 506 of FIG. 5 which requires more transmission power to reliably transmit. However, some UEs, such as NR-Light UEs, have a lower maximum transmission power than other UE types, which may result in transmission failure for the Msg-A preamble of 402 of FIG. 4 or 506 of FIG. 5. For power-constrained UEs, the Msg-A preamble of 402 of FIG. 4 or 506 of FIG. 5 could be transported more reliability via the use of one or more transmission repetitions. However, conventional systems do not permit a Msg-A payload repetition level to be indicated via Msg-A preamble.

FIG. 8 illustrates an exemplary process 800 of wireless communications according to an aspect of the disclosure. The process 800 of FIG. 8 is performed by UE 120.

At 802, UE 120 (e.g., controller/processor 240) identifies a set of ROs over which to transmit a preamble (e.g., a Msg-A preamble for a 2-Step RACH procedure) associated with a RACH procedure. In an example, the identification of 802 may comprise a selection of a set of ROs among a plurality of sets of ROs based on one or more signal reception quality measurements. For example, the plurality of sets of ROs may comprise a first set of ROs dedicated to a first UE class (e.g., power-constrained UEs such as NR-Light UEs) and a second set of ROs shared between the first UE class and a second UE class (e.g., UEs that do not have the power constraints associated with the first UE class) . In an example, the identification of 802 may comprise a selection that is based on a relationship between the one or more signal reception quality measurements and at least one signal reception quality measurement threshold. For example, at 802, the first set of ROs may be selected if the one or more signal reception quality measurements are less than the at least one signal reception quality measurement threshold, and the second set of ROs may be selected if the one or more signal reception quality measurements are not less than the at least one signal reception quality measurement threshold. In this case, in an example, lower-performing UEs of the first UE class may select the first set of ROs, while higher-performing UEs of the first UE class may select the second set of ROs (which may also be used by UEs of the second UE class without requiring execution of the process 800 of FIG. 8 thereon) . In some designs, the at least one signal reception quality measurement threshold is pre-defined (e.g., in the relevant 3GPP standard) , while in other designs the at least one signal reception quality measurement threshold is configured dynamically (e.g., via a SIB such as SIB1 or via RRC signaling) . In other designs, the set of ROs can be identified at 802 in some other manner and need not be based upon the one or more signal reception quality measurements. In an example, each set of ROs among the plurality of sets of ROs may be associated with a different preamble format, whereby each preamble format comprises a group of parameters including but not limited to sequence length, SCS, BW, CP length, guard time duration, total TD duration, etc. In an example, the plurality of sets of ROs may comprise at least one frequency divisional multiplexed (FDMed) set of ROs, at least one time division multiplexed (TDMed) set of ROs, and/or at least one set of ROs that non-orthogonally multiplexed.

At 804, UE 120 (e.g., controller/processor 280) selects a first preamble sequence group from among a plurality of preamble sequence groups associated with the identified set of ROs based on a repetition level preference for an uplink message (e.g., a Msg-A payload) on one or more physical uplink shared channel (PUSCH) opportunities (POs) , wherein each of the plurality of preamble sequence groups is associated with a different repetition level for the uplink message. In an aspect, the uplink message is associated with the RACH procedure (e.g., Msg-A payload or PUSCH, etc. ) and is subsequent to the preamble transmission. In a further aspect, each of the plurality of preamble sequence groups may be associated with a different repetition level for the uplink message. In some designs, the repetition level preference may be based upon one or more signal reception quality measurements. In some designs, the association between each of the plurality of preamble sequence groups and its respective repetition level for the uplink message is pre-defined (e.g., in the relevant 3GPP standard) . In other designs, information indicative of the association between each of the plurality of preamble sequence groups and its respective repetition level for the uplink message is received from a base station (e.g., via radio resource control (RRC) signaling or remaining minimum system information (RMSI) signaling or SIB1) .

At 806, the UE 120 (e.g., antenna (s) 252a ... 252r, TX MIMO processor 266, modulators (s) 254a ... 254r, TX processor 264) transmits the preamble on the identified group of ROs. In an example, the preamble transmitted at 806 may correspond to a Msg-A payload (or PUSCH) of a 2-Step PRACH procedure. In some designs, the preamble of 806 may be configured to indicate to the base station that subsequent Msg-A payload or PUSCH will be transmitted with a particular number of repetitions, as will be described below in more detail.

At 808, the UE 120 (e.g., antenna (s) 252a ... 252r, TX MIMO processor 266, modulators (s) 254a ... 254r, TX processor 264) transmits, before a response to the preamble from 806 is received, the uplink message on a first set of POs associated with the selected preamble sequence group, wherein the first set of POs corresponds to a first repetition level associated with the selected preamble sequence group. In an example, the first set of POs corresponds to inter-slot PUSCH repetitions. In some designs, similar to the identified set of ROs, the first set of POs may be configured via RRC signaling, RMSI signaling, or SIB1.

FIG. 9 illustrates an exemplary process 900 of wireless communications according to an aspect of the disclosure. The process 900 of FIG. 6 is performed by BS 110.

At 902, BS 110 (e.g., antenna (s) 234a ... 234t, demodulators (s) 232a ... 232a, MIMO detector 236, RX processor 238) receives, from a UE, a preamble associated with a RACH procedure (e.g., a Msg-A preamble of a 2-Step PRACH procedure) over one of a plurality of sets of ROs, wherein the set of ROs over which the preamble is received is associated with one of a plurality of preamble sequence groups, wherein each of the plurality of preamble sequence groups is associated with a different repetition level for an uplink message (e.g., Msg-A payload or PUSCH) associated with the RACH procedure on one or more POs. In some designs, the identified set of ROs includes a plurality of ROs, while in other designs, the identified set of ROs includes a single RO. In some designs, each of the plurality of sets of ROs is associated with a different preamble format.

At 904, BS 110 (e.g., controller/processor 240) identifies a set of POs for the uplink message based on the preamble sequence group associated with the set of ROs over which the preamble is received, wherein the first set of POs corresponds to the repetition level for the associated preamble sequence group. In some designs, the first set of POs correspond to inter-slot PUSCH repetitions. In some designs, the first set of POs may be configured via RRC signaling, RMSI signaling, or SIB1.

At 906, BS 110 (e.g., antenna (s) 234a ... 234t, demodulators (s) 232a ... 232a, MIMO detector 236, RX processor 238) receives, from the UE before a response to the preamble is transmitted, the uplink message on the first set of POs in accordance with the corresponding repetition level. In an example, the first set of POs corresponds to inter-slot PUSCH repetitions. In some designs, similar to the identified set of ROs, the first set of POs may be configured via RRC signaling, RMSI signaling, or SIB1.

Referring to FIGS. 8-9, in some designs, wherein the plurality of preamble sequence groups includes a second preamble sequence group that is associated with a second repetition level for the uplink message. The second preamble sequence may be associated with a second set of POs corresponding to the second repetition level. In an example, the first and second sets of POs may be multiplexed in accordance with an FDM scheme, a TDM scheme, or a combination thereof. In a further example, the first and second sets of POs may be multiplexed in accordance with a non-orthogonal or overlapping multiplexing scheme.

Referring to FIGS. 8-9, in a further example, assume that the first set of POs and the second set of POs are multiplexed in accordance with the non-orthogonal or overlapping multiplexing scheme. In this case, in an example, the first set of POs may be associated with a first demodulation reference signal (DMRS) resource, and the second set of POs is associated with a second DMRS resource, whereby the first DMRS resource and the second DMRS resource are orthogonal with each other or comprise a cross-correlation with each other that is below a threshold. In a further example, the identified set of ROs and a set of ROs associated with the second preamble sequence group are orthogonal to each other. In an alternative example, the identified set of ROs and the set of ROs associated with the second preamble sequence group are the same set of ROs.

Referring to FIGS. 8-9, in some designs, the repetition level preference is based on one or more of a transmission power associated with the UE, a number of transmission antennas associated with the UE, a PUSCH payload size associated with the first set of POs, a power offset from the preamble transmission to the PUSCH-based uplink message transmission, or any combination thereof. In a further example, the power offset is configured via RRC signaling, RMSI signaling, or SIB1.

FIG. 10A illustrates an RO-PO configuration 1000A comprising various sets of POs that are each associated with different repetition levels for a Msg-A payload in accordance with an embodiment of the disclosure. In particular, PO set A is associated with a repetition level of 1, PO set B is associated with a repetition level of 2, and PO set C is associated with a repetition level of 4. In FIG. 10A, PO sets A-C are FDMed. In FIG. 10A, ROs #1 through #5 (which each represent a respective set of ROs) are orthogonally configured with different preamble formats. In context with FIGS. 8-9, the preamble sequence group used to transport the Msg-A preamble on a respective RO can be used to indicate whether the Msg-B payload will be transported via PO set A (1 repetition) , PO set B (2 repetitions) or PO set C (4 repetitions) .

FIG. 10B illustrates an RO-PO configuration 1000B comprising various sets of POs that are each associated with different repetition levels for a Msg-A payload in accordance with an embodiment of the disclosure. In particular, PO set A is associated with a repetition level of 1, PO set B is associated with a repetition level of 2, and PO set C is associated with a repetition level of 4. In FIG. 10B, PO sets A-C are non-orthogonally multiplexed . In FIG. 10B, ROs #1 through #2 (which each represent a respective set of ROs) are orthogonally configured with different preamble formats. In context with FIGS. 8-9, the preamble sequence group used to transport the Msg-A preamble on a respective RO can be used to indicate whether the Msg-B payload will be transported via PO set A (1 repetition) , PO set B (2 repetitions) or PO set C (4 repetitions) . Further depicted in FIG. 10B are orthogonal or low-correlation DMRS resources.

FIG. 11 illustrates an example implementation 1100 of the processes 800-900 of FIGS. 8-9 in accordance with an embodiment of the disclosure. The process 1100 constitutes a modified version of the 2-Step PRACH procedure 400 of FIG. 4 or 500 of FIG. 5. At 1102, BS 110 optionally transmits RO configuration information and/or PO configuration information to UE 120 (e.g., via RMSI signaling, RRC signaling, or SIB1) . At 1104, BS 110 optionally transmits a downlink signal (e.g., PSS/SSS) , and at 1106 UE 120 optionally receives and measures the downlink signal. At 1108 (e.g., as in 802 of FIG. 8) , UE 120 identifies a set of ROs (e.g., via selection based on the downlink signal measurement (s) from 1106) . At 1110 (e.g., as in 804 of FIG. 8) , UE 120 selects a preamble sequence group to be used on the selected RO group in association with a repetition level preference of UE 120. At 1112 (e.g., as in 806 of FIG. 8 or 902 of FIG. 9) , UE 120 transmits Msg-A preamble (or PRACH preamble) to BS 110. At 1114 (e.g., as in 904 of FIG. 9) , BS 110 identifies a Msg-A payload repetition level from the Msg-A preamble of 1112 (e.g., based on which preamble sequence group was used, etc. ) . At 1116, UE 120 transmits Msg-A payload (e.g., one or more PUSCH repetitions) to BS 110 (e.g., in accordance with the repetition level indicated by Msg-A preamble) . At 1118, BS 110 processes the Msg-A PRACH preamble from 1112. At 1120, BS 110 processes the Msg-A payload from 1116. At 1122, BS 110 transmits a Msg-B RAR via PDCCH. At 1124, BS 110 transmits Msg-B contention resolution information via PDCCH. At 1126, UE 120 and BS 110 may optionally exchange user data.

FIG. 12 is a conceptual data flow diagram 1200 illustrating the data flow between different means/components in

exemplary apparatuses

1202 and 1280 in accordance with an embodiment of the disclosure. The apparatus 1202 may be a UE (e.g., UE 120) in communication with an apparatus 1280, which may be a base station (e.g., base station 110) .

The apparatus 1202 includes a transmission component 1204, which may correspond to transmitter circuitry in UE 120 as depicted in FIG. 2, including controller/processor 280, antenna (s) 252a ... 252r, modulators (s) 254a ... 254r, TX MIMO processor 266, TX processor 264. The apparatus 1202 further includes an RO /PO selection component 1206, which may correspond to processor circuitry in UE 120 as depicted in FIG. 2, including controller/processor 280, etc. The apparatus 1202 further includes a reception component 1208, which may correspond to receiver circuitry in UE 120 as depicted in FIG. 2, including controller/processor 280, antenna (s) 252a ... 252r, demodulators (s) 254a ... 254r, MIMO detector 256, RX processor 258.

The apparatus 1280 includes a reception component 1282, which may correspond to receiver circuitry in BS 110 as depicted in FIG. 2, including controller/processor 240, antenna (s) 234a ... 234r, demodulators (s) 232a ... 232r, MIMO detector 236, RX processor 238, communication unit 244. The apparatus 1280 further optionally includes a PO identifying component 1284, which may correspond to processor circuitry in BS 110 as depicted in FIG. 2, including controller/processor 240. The apparatus 1280 further includes a transmission component 1286, which may correspond to transmission circuitry in BS 110 as depicted in FIG. 2, including e.g., controller/processor 240, antenna (s) 234a ... 234r, modulators (s) 232a ... 232r, Tx MIMO processor 230, TX processor 220, communication unit 244.

Referring to FIG. 12, the transmission component 1286 optionally sends RO /PO configuration information to the reception component 1208, which may be factored into RO /PO selections by the RO /PO selection component 1206. The transmission component 1204 may transmit Msg-A PRACH preambles and Msg-A payloads (e.g., PUSCH (s) comprising UE identifying information) to the reception component 1282 (e.g., based on RO /PO selections from the RO /PO selection component 1206) . The PO identifying component 1284 may determine a repetition level for the Msg-A payload based on a preamble sequence group associated with the Msg-A PRACH preamble. The transmission component 1286 may transmit Msg-B (PDCCH) and Msg-B (PDSCH) in response to the Msg-A transmissions. After the 2-Step PRACH procedure, the transmission component 1204 and the reception component 1282 may exchange user data, and the transmission component 1286 and the reception component 1208 may likewise exchange user data.

One or more components of the apparatus 1202 and apparatus 1280 may perform each of the blocks of the algorithm in the aforementioned flowcharts of FIGS. 8-9. As such, each block in the aforementioned flowcharts of FIGS. 8-9 may be performed by a component and the apparatus 1202 and apparatus 1280 may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof.

FIG. 13 is a diagram 1300 illustrating an example of a hardware implementation for an apparatus 1202 employing a processing system 1314. The processing system 1314 may be implemented with a bus architecture, represented generally by the bus 1324. The bus 1324 may include any number of interconnecting buses and bridges depending on the specific application of the processing system 1314 and the overall design constraints. The bus 1324 links together various circuits including one or more processors and/or hardware components, represented by the processor 1304, the

components

1204, 1206 and 1208, and the computer-readable medium /memory 1306. The bus 1324 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further.

The processing system 1314 may be coupled to a transceiver 1310. The transceiver 1310 is coupled to one or more antennas 1320. The transceiver 1310 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 1310 receives a signal from the one or more antennas 1320, extracts information from the received signal, and provides the extracted information to the processing system 1314, specifically the reception component 1208. In addition, the transceiver 1310 receives information from the processing system 1314, specifically the transmission component 1204, and based on the received information, generates a signal to be applied to the one or more antennas 1320. The processing system 1314 includes a processor 1304 coupled to a computer-readable medium /memory 1306. The processor 1304 is responsible for general processing, including the execution of software stored on the computer-readable medium /memory 1306. The software, when executed by the processor 1304, causes the processing system 1314 to perform the various functions described supra for any particular apparatus. The computer-readable medium /memory 1306 may also be used for storing data that is manipulated by the processor 1304 when executing software. The processing system 1314 further includes at least one of the

components

1204, 1206 and 1208. The components may be software components running in the processor 1304, resident/stored in the computer readable medium /memory 1306, one or more hardware components coupled to the processor 1304, or some combination thereof. The processing system 1314 may be a component of the UE 120 of FIG. 2 and may include the memory 282, and/or at least one of the TX processor 264, the RX processor 258, and the controller/processor 280.

In one configuration, the apparatus 1202 (e.g., a UE) for wireless communication includes means for identifying a set of random access channel (RACH) opportunities (ROs) over which to transmit a preamble associated with a RACH procedure, means for selecting a first preamble sequence group from among a plurality of preamble sequence groups associated with the identified set of ROs based on a repetition level preference for an uplink message on one or more physical uplink shared channel (PUSCH) opportunities (POs) , wherein each of the plurality of preamble sequence groups is associated with a different repetition level for the uplink message, means for transmitting the preamble on the identified set of ROs, and means for transmitting, before a response to the preamble is received, the uplink message on a first set of POs associated with the selected preamble sequence group, wherein the first set of POs corresponds to a first repetition level associated with the selected preamble sequence group. The aforementioned means may be one or more of the aforementioned components of the apparatus 1202 and/or the processing system 1314 of the apparatus 1202 configured to perform the functions recited by the aforementioned means. As described supra, the processing system 1314 may include the TX processor 264, the RX processor 258, and the controller/processor 280.

FIG. 14 is a diagram 1400 illustrating an example of a hardware implementation for an apparatus 1280 employing a processing system 1414. The processing system 1414 may be implemented with a bus architecture, represented generally by the bus 1424. The bus 1424 may include any number of interconnecting buses and bridges depending on the specific application of the processing system 1414 and the overall design constraints. The bus 1424 links together various circuits including one or more processors and/or hardware components, represented by the processor 1404, the

components

1282, 1284 and 1286, and the computer-readable medium /memory 1406. The bus 1424 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further.

The processing system 1414 may be coupled to a transceiver 1410. The transceiver 1410 is coupled to one or more antennas 1420. The transceiver 1410 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 1410 receives a signal from the one or more antennas 1420, extracts information from the received signal, and provides the extracted information to the processing system 1414, specifically the reception component 1282. In addition, the transceiver 1410 receives information from the processing system 1414, specifically the transmission component 1286, and based on the received information, generates a signal to be applied to the one or more antennas 1420. The processing system 1414 includes a processor 1404 coupled to a computer-readable medium /memory 1406. The processor 1404 is responsible for general processing, including the execution of software stored on the computer-readable medium /memory 1406. The software, when executed by the processor 1404, causes the processing system 1414 to perform the various functions described supra for any particular apparatus. The computer-readable medium /memory 1406 may also be used for storing data that is manipulated by the processor 1404 when executing software. The processing system 1414 further includes at least one of the

components

1282, 1284 and 1286. The components may be software components running in the processor 1404, resident/stored in the computer readable medium /memory 1406, one or more hardware components coupled to the processor 1404, or some combination thereof. The processing system 1414 may be a component of the BS 110 of FIG. 2 and may include the memory 242, and/or at least one of the TX processor 220, the RX processor 238, and the controller/processor 240.

In one configuration, the apparatus 1280 (e.g., a BS) for wireless communication includes means for receiving, from a UE, a preamble associated with a RACH procedure over one of a plurality of sets of ROs, wherein the set of ROs over which the preamble is received is associated with one of a plurality of preamble sequence groups, wherein each of the plurality of preamble sequence groups is associated with a different repetition level for an uplink message associated with the RACH procedure on one or more POs, means for identifying a first set of POs for the uplink message based on the preamble sequence group associated with the set of ROs over which the preamble is received, wherein the first set of POs corresponds to the repetition level for the associated preamble sequence group, and means for receiving, from the UE before a response to the preamble is transmitted, the uplink message on the first set of POs in accordance with the corresponding repetition level. The aforementioned means may be one or more of the aforementioned components of the apparatus 1280 and/or the processing system 1114 of the apparatus 1280 configured to perform the functions recited by the aforementioned means. As described supra, the processing system 1414 may include the TX processor 220, the RX processor 238, and the controller/processor 240.

As used herein, the term “component” is intended to be broadly construed as hardware, firmware, and/or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, and/or a combination of hardware and software.

As used herein, satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.

It will be apparent that systems and/or methods described herein may be implemented in different forms of hardware, firmware, and/or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described herein without reference to specific software code-it being understood that software and hardware can be designed to implement the systems and/or methods based, at least in part, on the description herein.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like) , and may be used interchangeably with “one or more. ” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” and/or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.

Claims

A method of operating a user equipment (UE) , comprising:

identifying a set of random access channel (RACH) opportunities (ROs) over which to transmit a preamble associated with a RACH procedure;

selecting a first preamble sequence group from among a plurality of preamble sequence groups associated with the identified set of ROs based on a repetition level preference for an uplink message on one or more physical uplink shared channel (PUSCH) opportunities (POs) , wherein each of the plurality of preamble sequence groups is associated with a different repetition level for the uplink message;

transmitting the preamble on the identified set of ROs; and

transmitting, before a response to the preamble is received, the uplink message on a first set of POs associated with the selected preamble sequence group, wherein the first set of POs corresponds to a first repetition level associated with the selected preamble sequence group.
The method of claim 1, wherein the first set of POs correspond to inter-slot PUSCH repetitions.
The method of claim 1, wherein configurations of the set of ROs and the first set of POs are configured via radio resource control (RRC) signaling or remaining minimum system information (RMSI) signaling.
The method of claim 1, wherein each of the plurality of sets of ROs is associated with a different preamble format.
The method of claim 1,

wherein the RACH procedure is a 2-Step Physical (RACH) (PRACH) procedure, and

wherein the preamble and the uplink message collectively correspond to Msg-Aof the 2-Step PRACH procedure.
The method of claim 1,

wherein the plurality of preamble sequence groups includes a second preamble sequence group that is associated with a second repetition level for the uplink message, and

wherein the second preamble sequence is associated with a second set of POs corresponding to the second repetition level, and

wherein the first set of POs and the second set of POs are multiplexed in accordance with a frequency divisional multiplex (FDM) scheme, or

wherein the first set of POs and the second set of POs are multiplexed in accordance with a time divisional multiplex (TDM) scheme, or

wherein the first set of POs and the second set of POs are multiplexed in accordance with a non-orthogonal or overlapping multiplexing scheme.
The method of claim 6,

wherein the first set of POs and the second set of POs are multiplexed in accordance with the non-orthogonal or overlapping multiplexing scheme,

wherein the first set of POs is associated with a first demodulation reference signal (DMRS) resource, and the second set of POs is associated with a second DMRS resource, and

wherein the first DMRS resource and the second DMRS resource are orthogonal with each other or comprise a cross-correlation with each other that is below a threshold.
The method of claim 6,

wherein the identified set of ROs and a set of ROs associated with the second preamble sequence group are orthogonal to each other, or

wherein the identified set of ROs and the set of ROs associated with the second preamble sequence group are the same set of ROs.
The method of claim 1, wherein the repetition level preference is based on one or more of:

a transmission power associated with the UE,

a number of transmission antennas associated with the UE,

a PUSCH payload size associated with the first set of POs,

a power offset from the preamble transmission to the PUSCH-based uplink message transmission.
The method of claim 9, wherein the power offset is configured via radio resource control (RRC) signaling or remaining minimum system information (RMSI) signaling.
A method of operating a base station, comprising:

receiving, from a user equipment (UE) , a preamble associated with a random access channel (RACH) procedure over one of a plurality of sets of RACH opportunities (ROs) , wherein the set of ROs over which the preamble is received is associated with one of a plurality of preamble sequence groups, wherein each of the plurality of preamble sequence groups is associated with a different repetition level for an uplink message associated with the RACH procedure on one or more physical uplink shared channel (PUSCH) opportunities (POs) ;

identifying a first set of POs for the uplink message based on the preamble sequence group associated with the set of ROs over which the preamble is received, wherein the first set of POs corresponds to the repetition level for the associated preamble sequence group; and

receiving, from the UE before a response to the preamble is transmitted, the uplink message on the first set of POs in accordance with the corresponding repetition level.
The method of claim 11,

wherein the identified set of ROs includes a plurality of ROs, and

wherein the identified set of ROs includes a single RO.
The method of claim 11, wherein the first set of POs correspond to inter-slot PUSCH repetitions.
The method of claim 13, wherein configurations of the set of ROs and the first set of POs are configured via radio resource control (RRC) signaling or remaining minimum system information (RMSI) signaling.
The method of claim 11, wherein each of the plurality of sets of ROs is associated with a different preamble format.
The method of claim 11,

wherein the RACH procedure is a 2-Step Physical (RACH) (PRACH) procedure, and

wherein the preamble and the uplink message collectively correspond to Msg-Aof the 2-Step PRACH procedure.
The method of claim 11,

wherein the plurality of preamble sequence groups includes a second preamble sequence group that is associated with a second repetition level for the uplink message, and

wherein the second preamble sequence is associated with a second set of POs corresponding to the second repetition level, and

wherein the first set of POs and the second set of POs are multiplexed in accordance with a frequency divisional multiplex (FDM) scheme, or

wherein the first set of POs and the second set of POs are multiplexed in accordance with a time divisional multiplex (TDM) scheme, or

wherein the first set of POs and the second set of POs are multiplexed in accordance with a non-orthogonal or overlapping multiplexing scheme.
The method of claim 17,

wherein the first set of POs and the second set of POs are multiplexed in accordance with the non-orthogonal or overlapping multiplexing scheme,

wherein the first set of POs is associated with a first demodulation reference signal (DMRS) resource, and the second set of POs is associated with a second DMRS resource, and

wherein the first DMRS resource and the second DMRS resource are orthogonal with each other or comprise a cross-correlation with each other that is below a threshold.
The method of claim 11,

wherein the identified set of ROs and a set of ROs associated with the second preamble sequence group are orthogonal to each other, or

wherein the identified set of ROs and the set of ROs associated with the second preamble sequence group are the same set of ROs.
The method of claim 11, wherein the repetition level preference is based on one or more of:

a transmission power associated with the UE,

a number of transmission antennas associated with the UE,

a PUSCH payload size associated with the first set of POs,

a power offset from the preamble transmission to the PUSCH-based uplink message transmission.
The method of claim 21, wherein the power offset is configured via radio resource control (RRC) signaling or remaining minimum system information (RMSI) signaling.
A user equipment (UE) , comprising:

means for identifying a set of random access channel (RACH) opportunities (ROs) over which to transmit a preamble associated with a RACH procedure;

means for selecting a first preamble sequence group from among a plurality of preamble sequence groups associated with the identified set of ROs based on a repetition level preference for an uplink message on one or more physical uplink shared channel (PUSCH) opportunities (POs) , wherein each of the plurality of preamble sequence groups is associated with a different repetition level for the uplink message;

means for transmitting the preamble on the identified set of ROs; and

means for transmitting, before a response to the preamble is received, the uplink message on a first set of POs associated with the selected preamble sequence group, wherein the first set of POs corresponds to a first repetition level associated with the selected preamble sequence group.
A base station, comprising:

means for receiving, from a user equipment (UE) , a preamble associated with a random access channel (RACH) procedure over one of a plurality of sets of RACH opportunities (ROs) , wherein the set of ROs over which the preamble is received is associated with one of a plurality of preamble sequence groups, wherein each of the plurality of preamble sequence groups is associated with a different repetition level for an uplink message associated with the RACH procedure on one or more physical uplink shared channel (PUSCH) opportunities (POs) ;

means for identifying a first set of POs for the uplink message based on the preamble sequence group associated with the set of ROs over which the preamble is received, wherein the first set of POs corresponds to the repetition level for the associated preamble sequence group; and

means for receiving, from the UE before a response to the preamble is transmitted, the uplink message on the first set of POs in accordance with the corresponding repetition level.
A user equipment (UE) , comprising:

a memory; and

at least one processor coupled to the memory and configured to:

identify a set of random access channel (RACH) opportunities (ROs) over which to transmit a preamble associated with a RACH procedure;

select a first preamble sequence group from among a plurality of preamble sequence groups associated with the identified set of ROs based on a repetition level preference for an uplink message on one or more physical uplink shared channel (PUSCH) opportunities (POs) , wherein each of the plurality of preamble sequence groups is associated with a different repetition level for the uplink message;

transmit the preamble on the identified set of ROs; and

transmit, before a response to the preamble is received, the uplink message on a first set of POs associated with the selected preamble sequence group, wherein the first set of POs corresponds to a first repetition level associated with the selected preamble sequence group.
A base station, comprising:

a memory; and

at least one processor coupled to the memory and configured to:

receive, from a user equipment (UE) , a preamble associated with a random access channel (RACH) procedure over one of a plurality of sets of RACH opportunities (ROs) , wherein the set of ROs over which the preamble is received is associated with one of a plurality of preamble sequence groups, wherein each of the plurality of preamble sequence groups is associated with a different repetition level for an uplink message associated with the RACH procedure on one or more physical uplink shared channel (PUSCH) opportunities (POs) ;

identify a first set of POs for the uplink message based on the preamble sequence group associated with the set of ROs over which the preamble is received, wherein the first set of POs corresponds to the repetition level for the associated preamble sequence group; and

receive, from the UE before a response to the preamble is transmitted, the uplink message on the first set of POs in accordance with the corresponding repetition level.
A non-transitory computer-readable medium containing instructions stored thereon, for causing at least one processor in a user equipment (UE) to:

identify a set of random access channel (RACH) opportunities (ROs) over which to transmit a preamble associated with a RACH procedure;

select a first preamble sequence group from among a plurality of preamble sequence groups associated with the identified set of ROs based on a repetition level preference for an uplink message on one or more physical uplink shared channel (PUSCH) opportunities (POs) , wherein each of the plurality of preamble sequence groups is associated with a different repetition level for the uplink message;

transmit the preamble on the identified set of ROs; and

transmit, before a response to the preamble is received, the uplink message on a first set of POs associated with the selected preamble sequence group, wherein the first set of POs corresponds to a first repetition level associated with the selected preamble sequence group.
A non-transitory computer-readable medium containing instructions stored thereon, for causing at least one processor in a base station to:

receive, from a user equipment (UE) , a preamble associated with a random access channel (RACH) procedure over one of a plurality of sets of RACH opportunities (ROs) , wherein the set of ROs over which the preamble is received is associated with one of a plurality of preamble sequence groups, wherein each of the plurality of preamble sequence groups is associated with a different repetition level for an uplink message associated with the RACH procedure on one or more physical uplink shared channel (PUSCH) opportunities (POs) ;

identify a first set of POs for the uplink message based on the preamble sequence group associated with the set of ROs over which the preamble is received, wherein the first set of POs corresponds to the repetition level for the associated preamble sequence group; and

receive, from the UE before a response to the preamble is transmitted, the uplink message on the first set of POs in accordance with the corresponding repetition level.