Design considerations for a random access response for a two-step random access procedure

Abstract

The various forms of this application generally relate to wireless communication. A user equipment (UE) can transmit random access messages including a preamble and a payload. A base station can detect the preamble of the random access message. The base station may fail to decode or successfully decode the payload of the random access message. The base station can transmit a random access response, at least in part, based on the detection of the preamble and different decoding results for the payload. The random access response may include uplink group grants for multiple UEs sharing the same time-frequency timing and an indication of the type of uplink group grant. The UE can monitor the type and content of the uplink group grants and subsequently transmit data on the shared time-frequency resource set. Many other forms are provided.

Description

Technical Field

[0001] Aspects of the present disclosure generally relate to wireless communication and, more particularly, to techniques and apparatus for random access responses for a two-step random access procedure. Background Art

[0002] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcast. A typical wireless communication system may employ a multiple access technology capable of supporting communication with multiple user equipments (UEs) by sharing available system resources, such as bandwidth, transmission power, etc. 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, Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE / LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile service standard released by the 3rd Generation Partnership Project (3GPP).

[0003] A wireless communication network may include multiple base stations (BSs) capable of supporting communication with multiple user equipments (UEs). A user equipment (UE) may communicate with a base station (BS) via a downlink and an uplink. The downlink (or forward link) refers to the communication link from the BS to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail herein, a BS may be referred to as a Node B, gNB, access point (AP), radio head, transmission reception point (TRP), New Radio (NR) BS, 5G Node B, etc.

[0004] The above multiplex access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipments to communicate at the city, national, regional, or even global levels. New Radio (NR), which may also be referred to as 5G, is a set of enhancements to the LTE mobile service standard released by the 3rd Generation Partnership Project (3GPP). NR is designed to better support mobile broadband Internet access by improving spectral efficiency, reducing costs, enhancing services, utilizing new spectrums, and better integrating with other open standards by using Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) (CP-OFDM) on the downlink (DL), and CP-OFDM and / or SC-FDM (e.g., also referred to as Discrete Fourier Transform Spread OFDM (DFT-s-OFDM)) on the uplink (UL), as well as supporting beamforming, Multiple-Input Multiple-Output (MIMO) antenna technology, and carrier aggregation. However, with the increasing demand for mobile broadband access, there is a need for further improvement in LTE and NR technologies. Preferably, such improvements should be applicable to other multiplex access technologies and telecommunication standards using such technologies. Summary of the Invention

[0005] In some aspects, a method of wireless communication performed by a user equipment (UE) may include the steps of: transmitting a preamble signal and a payload of a random access message associated with a two-step random access procedure; receiving a random access response associated with the two-step random access procedure, the random access response including an uplink group grant for a plurality of UEs including the UE and an indication of the type of the uplink group grant; and transmitting uplink communication on a shared time-frequency resource set based at least in part on the uplink group grant.

[0006] In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: transmit a preamble signal and a payload of a random access message associated with a two-step random access procedure; receive a random access response associated with the two-step random access procedure, the random access response including an uplink group grant for a plurality of UEs including the UE and an indication of the type of the uplink group grant; and transmit uplink communication on a shared time-frequency resource set based at least in part on the uplink group grant.

[0007] In some aspects, a non-transitory computer-readable medium can store one or more instructions for wireless communication. When executed by one or more processors of a UE, the one or more instructions can cause the one or more processors to: transmit a preamble signal and a payload of a random access message associated with a two-step random access procedure; receive a random access response associated with the two-step random access procedure, the random access response including an uplink group grant for a plurality of UEs including the UE and an indication of a type of the uplink group grant; and transmit uplink communication on a shared time-frequency resource set based at least in part on the uplink group grant.

[0008] In some aspects, a device for wireless communication can include: means for transmitting a preamble signal and a payload of a random access message associated with a two-step random access procedure; means for receiving a random access response associated with the two-step random access procedure, the random access response including an uplink group grant for a plurality of devices including the device and an indication of a type of the uplink group grant; and means for transmitting uplink communication on a shared time-frequency resource set based at least in part on the uplink group grant.

[0009] In some aspects, a method of wireless communication performed by a base station can include the steps of: detecting a preamble signal of a random access message associated with a two-step random access procedure, wherein the random access message is received from a user equipment (UE); processing a payload of the random access message, wherein a result of processing the payload is successfully decoding the payload or failing to decode the payload; and transmitting a random access response associated with the two-step random access procedure based at least in part on detecting the preamble signal and the result of processing the payload, wherein the random access response includes an uplink group grant for a plurality of UEs including the UE and an indication of a type of the uplink group grant, wherein preamble signal transmissions of the plurality of UEs share a time-frequency opportunity.

[0010] In some aspects, a base station for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: detect a preamble signal of a random access message associated with a two-step random access procedure, wherein the random access message is received from a user equipment (UE); process a payload of the random access message, wherein a result of processing the payload is successfully decoding the payload or failing to decode the payload; and transmit a random access response associated with the two-step random access procedure based at least in part on detecting the preamble signal and the result of processing the payload, wherein the random access response includes an uplink group grant for a plurality of UEs including the UE and an indication of a type of the uplink group grant, wherein preamble signal transmissions of the plurality of UEs share a time-frequency opportunity.

[0011] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. When executed by one or more processors of a base station, the one or more instructions may cause the one or more processors to: detect a preamble signal of a random access message associated with a two-step random access procedure, wherein the random access message is received from a user equipment (UE); process a payload of the random access message, wherein a result of processing the payload is successfully decoding the payload or failing to decode the payload; and transmit a random access response associated with the two-step random access procedure based at least in part on detecting the preamble signal and the result of processing the payload, wherein the random access response includes an uplink group grant for a plurality of UEs including the UE and an indication of a type of the uplink group grant, wherein preamble signal transmissions of the plurality of UEs share a time-frequency opportunity.

[0012] In some aspects, a device for wireless communication may include: means for detecting a preamble signal of a random access message associated with a two-step random access procedure, wherein the random access message is received from a user equipment (UE); means for processing a payload of the random access message, wherein a result of processing the payload is successfully decoding the payload or failing to decode the payload; and means for transmitting a random access response associated with the two-step random access procedure based at least in part on detecting the preamble signal and the result of processing the payload, wherein the random access response includes an uplink group grant for a plurality of UEs including the UE and an indication of a type of the uplink group grant, wherein preamble signal transmissions of the plurality of UEs share a time-frequency opportunity.

[0013] In some aspects, a method of wireless communication performed by a base station may include the steps of: constructing an uplink group grant for a plurality of UEs performing a two-step random access procedure, wherein a preamble signal or payload of a random access message provided by the plurality of UEs has been detected by the base station; and transmitting a random access response associated with the two-step random access procedure, wherein the random access response includes the uplink group grant and an indication of the type of the uplink group grant.

[0014] In some aspects, a method of wireless communication performed by a UE may include the steps of: transmitting a preamble signal and a payload of a random access message associated with a two-step random access procedure; and receiving a random access response associated with the two-step random access procedure after transmitting the preamble signal and the payload of the random access message, wherein the random access response includes an uplink group grant for a plurality of UEs including the UE, and wherein the random access response includes an indication of the type of the uplink group grant.

[0015] In some aspects, a base station for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: construct an uplink group grant for a plurality of UEs performing a two-step random access procedure, wherein a preamble signal or payload of a random access message provided by the plurality of UEs has been detected by the base station; and transmit a random access response associated with the two-step random access procedure, wherein the random access response includes the uplink group grant and an indication of the type of the uplink group grant.

[0016] In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: transmit a preamble signal and a payload of a random access message associated with a two-step random access procedure; and receive a random access response associated with the two-step random access procedure after transmitting the preamble signal and the payload of the random access message, wherein the random access response includes an uplink group grant for a plurality of UEs including the UE, and wherein the random access response includes an indication of the type of the uplink group grant.

[0017] In some aspects, a non-transitory computer-readable medium can store one or more instructions for wireless communication. When executed by one or more processors of a base station, the one or more instructions can cause the one or more processors to: configure an uplink group grant for a plurality of UEs performing a two-step random access procedure, wherein a preamble signal or payload of a random access message provided by the plurality of UEs has been detected by the base station; and transmit a random access response associated with the two-step random access procedure, wherein the random access response includes the uplink group grant and an indication of the type of the uplink group grant.

[0018] In some aspects, a non-transitory computer-readable medium can store one or more instructions for wireless communication. When executed by one or more processors of a UE, the one or more instructions can cause the one or more processors to: transmit a preamble signal and a payload of a random access message associated with a two-step random access procedure; and receive a random access response associated with the two-step random access procedure after transmitting the preamble signal and the payload of the random access message, wherein the random access response includes an uplink group grant for a plurality of UEs including the UE, and wherein the random access response includes an indication of the type of the uplink group grant.

[0019] In some aspects, a device for wireless communication can include: means for configuring an uplink group grant for a plurality of UEs performing a two-step random access procedure, wherein a preamble signal or payload of a random access message provided by the plurality of UEs has been detected by the base station; and means for transmitting a random access response associated with the two-step random access procedure, wherein the random access response includes the uplink group grant and an indication of the type of the uplink group grant.

[0020] In some aspects, a device for wireless communication can include: means for transmitting a preamble signal and a payload of a random access message associated with a two-step random access procedure; and means for receiving a random access response associated with the two-step random access procedure after transmitting the preamble signal and the payload of the random access message, wherein the random access response includes an uplink group grant for a plurality of UEs including the device, and wherein the random access response includes an indication of the type of the uplink group grant.

[0021] Generally, each aspect can include a method, a device, a system, a computer program product, a non-transitory computer-readable medium, a user equipment, a base station, a wireless communication device, and a processing system as fully described herein with reference to the accompanying drawings and the description and as shown in the accompanying drawings and the description.

[0022] The features and technical advantages of the examples according to the content of the present case have been outlined quite extensively above, so that the subsequent detailed description can be better understood. Other features and advantages will be described below. The concepts and specific examples disclosed can be easily used as a basis for modifying or designing other structures for achieving the same purpose as the content of the present case. Such equivalent structures do not depart from the scope of the appended claims. When considered in conjunction with the accompanying drawings, the features of the concepts disclosed herein, its method of organization and operation, and the related advantages will be better understood. Each of the accompanying drawings is provided for purposes of illustration and description, and not as a definition of the limitations of the claims. Brief Description of the Drawings

[0023] To understand in detail the above features of the content of the present case, a more specific description of what was briefly outlined above can be obtained by referring to some of the aspects illustrated in the accompanying drawings. However, it should be noted that the drawings only illustrate some typical aspects of the content of the present case, and should not be considered as a limitation of its scope, as the description may allow other equivalent aspects. The same reference numerals in different drawings can identify the same or similar elements.

[0024] FIG. 1 is a block diagram conceptually illustrating an example of a wireless communication network according to various aspects of the content of the present case.

[0025] FIG. 2 is a block diagram conceptually illustrating an example of a base station communicating with a UE in a wireless communication network according to various aspects of the content of the present case.

[0026] FIGS. 3A - 3C are diagrams illustrating examples associated with a random access response for a two-step random access procedure according to various aspects of the content of the present case.

[0027] FIG. 4 is a diagram illustrating an exemplary process, such as performed by a base station, according to various aspects of the content of the present case.

[0028] FIG. 5 is a diagram illustrating an exemplary process, such as performed by a UE, according to various aspects of the content of the present case.

[0029] FIG. 6 is a diagram illustrating an exemplary process, such as performed by a base station, according to various aspects of the content of the present case.

[0030] FIG. 7 is a diagram illustrating an exemplary process, such as performed by a UE, according to various aspects of the content of the present case. Embodiments

[0031] The various aspects of the present disclosure are described more fully hereinafter with reference to the accompanying drawings. However, the present disclosure may be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout the present disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art. Based on the teachings herein, those skilled in the art should appreciate that the scope of the present disclosure is intended to cover any aspect of the present disclosure disclosed herein, whether implemented independently of or in combination with any other aspect of the present disclosure. For example, any number of the aspects described herein may be used to implement the apparatus or practice the method. Additionally, the scope of the present disclosure is intended to cover such apparatus or methods practiced using other structures, functions, or combinations of structures and functions in addition to or different from the various aspects of the present disclosure described herein. It should be understood that any aspect of the present disclosure disclosed herein may be embodied by one or more elements of a claim.

[0032] Several aspects of a telecommunications system will now be presented with reference to various devices and technologies. These devices and technologies will be described in detail below and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using hardware, software, or a combination thereof. Whether the elements are implemented as hardware or software depends on the particular application and design constraints imposed on the overall system.

[0033] It should be noted that although the present disclosure may use terms commonly associated with 3G and / or 4G wireless technologies to describe the various aspects, the aspects of the present disclosure may be applied to communication systems based on other generations, such as 5G and later, including NR technology.

[0034] FIG. 1 is a diagram of 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 or NR network. The wireless network 100 may include multiple 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 (UE) and may also be referred to as a base station, NR BS, Node B, gNB, 5G Node B (NB), access point, transmission reception point (TRP), etc. Each BS may provide communication coverage for a specific geographical area. In 3GPP, the term "cell" may represent the coverage area of a BS and / or the BS subsystem serving that coverage area, depending on the context in which the term is used.

[0035] The BS can provide communication coverage for macro cells, pico cells, femto cells, and / or other types of cells. A macro cell can cover a relatively large geographical area (e.g., with a radius of several kilometers) and can allow unrestricted access for UEs with a service subscription. A pico cell can cover a relatively small geographical area and can allow unrestricted access for UEs with a service subscription. A femto cell can cover a relatively small geographical area (e.g., a home) and can allow restricted access for UEs associated with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG)). The BS for a macro cell can be referred to as a macro BS. The BS for a pico cell can be referred to as a pico BS. The BS for a femto cell can be referred to as a femto BS or a home BS. In the example shown in FIG. 1, BS 110a can be a macro BS for macro cell 102a, BS 110b can be a pico BS for pico cell 102b, and BS 110c can be a femto BS for femto cell 102c. The BS can support one or more (e.g., three) cells. The terms “eNB”, “base station”, “NR BS”, “gNB”, “TRP”, “AP”, “Node B”, “5G NB”, and “cell” are used interchangeably herein.

[0036] In some aspects, the cell may not necessarily be stationary, and the geographical area of the cell can move according to the location of the mobile BS. In some aspects, the BSs can be interconnected with each other and / or interconnected to one or more other BSs or network nodes (not shown) in the access wireless network 100 via various types of backhaul interfaces such as direct physical connections, virtual networks, etc., using any suitable transmission network.

[0037] The wireless network 100 can also include relay stations. A relay station is an entity that can receive a data transmission from an upstream station (e.g., a BS or a UE) and transmit the data transmission to a downstream station (e.g., a UE or a BS). A relay station can also be a UE that can relay the transmissions of other UEs. In the example shown in FIG. 1, relay station 110d can communicate with macro BS 110a and UE 120d to facilitate communication between BS 110a and UE 120d. A relay station can also be referred to as a relay BS, a relay base station, a relay, etc.

[0038] The wireless network 100 can be a heterogeneous network including different types of BSs (e.g., macro BS, pico BS, femto BS, relay BS, etc.). These different types of BSs can have different transmission power levels, different coverage areas, and different impacts on interference in the wireless network 100. For example, a macro BS can have a high transmission power level (e.g., 5 to 40 watts), while pico BSs, femto BSs, and relay BSs can have lower transmission power levels (e.g., 0.1 to 2 watts).

[0039] The network controller 130 can be coupled to a group of BSs and provide coordination and control for these BSs. The network controller 130 can communicate with the BSs via a backhaul. The BSs can also communicate with each other directly or indirectly via a wireless or wired backhaul.

[0040] UEs 120 (e.g., 120a, 120b, 120c) can be distributed throughout the wireless network 100, and each UE can be stationary or mobile. UEs can also be referred to as access terminals, terminals, mobile stations, user units, stations, etc. A UE can 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 wireless phone, a wireless local loop (WLL) station, a tablet computer, a camera, a gaming device, a netbook, a smart computer, an ultrabook, a medical device or apparatus, a biometric sensor / device, a wearable device (smart watch, smart clothing, smart glasses, smart bracelet, smart jewelry (e.g., smart ring, smart bracelet, etc.)), an entertainment device (e.g., a music or video device, or a satellite radio device), a vehicle component or sensor, a smart meter / sensor, an industrial manufacturing device, a global positioning system device, or any other suitable device configured to communicate via a wireless or wired medium.

[0041] Some UEs can be considered machine type communication (MTC) or evolved or enhanced machine type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., which can communicate with a base station, another device (e.g., a remote device), or some other entity. A wireless node can provide a connection to or from a network (e.g., a wide area network such as the Internet or a cellular network) via a wired or wireless communication link. Some UEs can be considered Internet of Things (IoT) devices and / or can be implemented as narrowband IoT (NB-IoT) devices. Some UEs can be considered customer premise equipment (CPE). The UE 120 can be included within a housing that houses the components of the UE 120, such as a processor component, a memory component, etc.

[0042] Generally, any number of wireless networks can be deployed in a given geographical area. Each wireless network can support a specific RAT and can operate on one or more frequencies. The RAT can also be referred to as radio technology, air interface, etc. The frequency can also be referred to as carrier, frequency channel, etc. Each frequency can support a single RAT in a given geographical area to avoid interference between wireless networks of different RATs. In some cases, an NR or 5G RAT network can be deployed.

[0043] In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) can communicate directly using one or more sidelink channels (e.g., communicate with each other without using the base station 110 as an intermediary). For example, the UE 120 can use peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocols (e.g., which can include vehicle-to-vehicle (V2V) protocol, vehicle-to-infrastructure (V2I) protocol, etc.), mesh network, etc. to communicate. In such cases, the UE 120 can perform scheduling operations, resource selection operations, and / or other operations described elsewhere in this document as being performed by the base station 110.

[0044] As previously mentioned, FIG. 1 is provided as an example. Other examples may be different from the examples described with respect to FIG. 1.

[0045] FIG. 2 illustrates a block diagram of a design 200 of the base station 110 and the UE 120, which can be one of the base stations and one of the UEs in FIG. 1. The base station 110 can be equipped with T antennas 234a to 234t, and the UE 120 can be equipped with R antennas 252a to 252r, where generally T≥1 and R≥1.

[0046] At base station 110, transmission processor 220 may receive data from data sources 212 of one or more UEs, select one or more modulation and coding schemes (MCSs) for each UE based at least in part on a channel quality indicator (CQI) 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. Transmission processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI), etc.) and control information (e.g., CQI requests, grants, upper layer signaling, etc.) and provide administrative burden symbols and control symbols. Processor 220 may also generate reference symbols for reference signals (e.g., cell-specific reference signal (CRS)) and synchronization signals (e.g., primary synchronization signal (PSS) and secondary synchronization signal (SSS)). Transmission (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, control symbols, administrative burden symbols, and / or reference symbols (if applicable), and may provide T output symbol streams to T modulators (MOD) 232a through 232t. Each modulator 232 may process the corresponding output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The 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, a synchronization signal may be generated using position coding to convey additional information.

[0047] At the UE 120, antennas 252a through 252r may receive downlink signals from the base station 110 and / or other base stations, and may provide the received signals to demodulators (DEMOD) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, down-convert, and digitize) the received signal to obtain an input sample. Each demodulator 254 may further process the input sample (e.g., for OFDM, etc.) to obtain a received symbol. The MIMO detector 256 may obtain the received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols (if applicable), and provide the detected symbols. The receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for the UE 120 to the data sink 260, and provide decoded control information and system information to the controller / processor 280. The channel processor may determine a reference signal received power (RSRP), received signal strength indicator (RSSI), reference signal received quality (RSRQ), channel quality indicator (CQI), etc. In some aspects, one or more components of the UE 120 may be included in a housing.

[0048] On the uplink, at the UE 120, the transmit processor 264 may receive and process data from the data source 262 and control information from the controller / processor 280 (e.g., for reporting including RSRP, RSSI, RSRQ, CQI, etc.). The transmit processor 264 may also generate reference symbols for one or more reference signals. Symbols from the transmit processor 264 may be precoded (if applicable) by the TX MIMO processor 266, further processed (e.g., for DFT-s-OFDM, CP-OFDM, etc.) by the modulators 252a through 254r, and transmitted to the base station 110. At the base station 110, uplink signals from the UE 120 and other UEs may be received by the antenna 234, processed by the demodulator 232, detected (if applicable) by the MIMO detector 236, and further processed by the receive processor 238 to obtain decoded data and control information transmitted by the UE 120. The receive processor 238 may provide the decoded data to the data sink 239 and provide the decoded control information to the controller / processor 240. The base station 110 may include a communication unit 244 and communicate with the network controller 130 via the communication unit 244. The network controller 130 may include a communication unit 294, a controller / processor 290, and a memory 292.

[0049] The controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, and / or any other element of FIG. 2 may perform one or more techniques for a random access response for a two-step random access procedure, as described in more detail elsewhere herein. For example, the controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, and / or any other element of FIG. 2 may perform or direct the operations of, for example, process 400 of FIG. 4, process 500 of FIG. 5, and / or other processes described herein. Memories 242 and 282 may store data and code for the base station 110 and the UE 120, respectively. Scheduler 246 may schedule data transmission for the UE on the downlink and / or uplink.

[0050] In some aspects, the base station 110 may include: means for detecting a preamble signal of a random access message associated with a two-step random access procedure, wherein the random access message is received from the UE 120; means for processing the payload of the random access message, wherein the result of processing the payload is successfully decoding the payload or failing to decode the payload; and means for transmitting a random access response associated with the two-step random access procedure, at least in part based on detecting the preamble signal and the result of processing the payload, wherein the random access response includes uplink group grants for a plurality of UEs including the UE 120 and an indication of the type of uplink group grant, wherein the preamble signal transmissions of the plurality of UEs share a time-frequency opportunity; and so on. In some aspects, the above means may include one or more elements of the base station 110 described in connection with FIG. 2.

[0051] In some aspects, the base station 110 may include: means for constructing uplink group grants for a plurality of UEs 120 performing a two-step random access procedure, wherein a preamble signal or payload of a random access message provided by the plurality of UEs 120 has been detected by the base station; and means for transmitting a random access response associated with the two-step random access procedure, wherein the random access response includes the uplink group grant and an indication of the type of uplink group grant; and so on. In some aspects, the above means may include one or more elements of the base station 110 described in connection with FIG. 2.

[0052] In some aspects, the UE 120 may include: components for transmitting a preamble signal and a payload of a random access message associated with a two-step random access procedure; components for receiving a random access response associated with the two-step random access procedure, the random access response including an uplink group grant for a plurality of UEs including the UE 120 and an indication of the type of the uplink group grant; and components for transmitting uplink communication on a shared time-frequency resource set based at least in part on the uplink group grant; and so on. In some aspects, the above components may include one or more elements of the UE 120 described in connection with FIG. 2.

[0053] In some aspects, the UE 120 may include: components for transmitting a preamble signal and a payload of a random access message associated with a two-step random access procedure; and components for receiving a random access response associated with the two-step random access procedure after transmitting the preamble signal and the payload of the random access message, wherein the random access response includes an uplink group grant for a plurality of UEs including the UE, and wherein the random access response includes an indication of the type of the uplink group grant; and so on. In some aspects, the above components may include one or more elements of the UE 120 described in connection with FIG. 2.

[0054] As described above, FIG. 2 is provided as an example. Other examples may be different from the examples described with respect to FIG. 2.

[0055] The two-step random access channel (RACH) procedure includes two steps (instead of four steps in the traditional four-step RACH procedure). In the two-step RACH procedure, the UE transmits a random access message (referred to as msgA), which includes a preamble signal (e.g., randomly selected) and a payload (e.g., a physical uplink shared channel (PUSCH) payload). Ideally, the base station successfully detects the preamble signal and successfully decodes the payload, and transmits a random access response (referred to as msgB) to the UE. The random access response includes physical downlink control channel (PDCCH) communication and a physical downlink shared channel (PDSCH) payload, where the PDCCH communication identifies the resources of the PDSCH payload carrying information for the UE. The PDSCH payload may include, for example, contention resolution information for the UE, a cell radio network temporary identifier (C-RNTI) for the UE, a timing advance (TA) command for the UE, and so on. In such an ideal case (i.e., when the base station detects the msgA preamble signal and decodes the msgA payload), the random access response associated with the two-step RACH procedure is referred to herein as a SuccessRAR (Success Random Access Response).

[0056] However, in some cases, the base station may not detect the preamble signal of the random access message and / or may fail to decode the payload of the random access message. Such a situation may occur due to, for example, channel impairments, contention-based multiplexing access, etc. Therefore, to improve the reliability of the two-step RACH procedure, transmission of a fallback to another random access message (e.g., a message similar to msg3 in the traditional four-step RACH procedure) and / or retransmission of the random access message (e.g., retransmission of msgA) can be supported.

[0057] In the case where the base station successfully detects the preamble signal of the random access message but fails to decode the payload of the random access message, the base station may send a random access response including the following: a random access preamble identifier (RAPID) associated with the detected preamble signal, an uplink grant for the UE, a TA command for the UE, and a temporary C-RNTI (TC-RNTI) for the UE. The random access response associated with the two-step RACH procedure in the case of detecting the preamble signal but not successfully decoding the payload is referred to herein as a fallback random access response (FallbackRAR). Generally, when a UE executing the two-step RACH procedure receives the fallback random access response, the UE falls back to the four-step RACH procedure and, based on the received fallback random access response, transmits another random access message (e.g., msg3). Here, the content of the another random access message may be similar to or different from the content of the payload of the random access message transmitted by the UE during the two-step RACH attempt. It should be noted that the UE does not need to transmit the preamble signal together with the another random access message because the base station has already detected the preamble signal. In the case where the base station does not detect the preamble signal of the random access message, the base station may send fallback indication information in the random access response medium access control (MAC) sub-header (e.g., such that the UE can retransmit the random access message at a later time).

[0058] As described above, in the conventional two-step RACH procedure, the base station includes an uplink grant for the UE (e.g., a single-UE uplink grant) in a given fallback random access response, but does not include any uplink grant in the successful random access response. Such an uplink grant design for the two-step RACH may lead to inefficiencies in aspects such as spectral efficiency, power consumption, and signal delivery management burden.

[0059] Some aspects described herein provide uplink grant design improvements for two-step RACH procedures. For example, in some aspects, the uplink grant included in the shifted random access response can be an uplink group grant for a plurality of UEs (e.g., to allow a plurality of UEs to share uplink resources for further uplink transmissions). As another example, in some aspects, an uplink grant can be included in a successful random access response (e.g., to allow a UE to send additional uplink data without requesting uplink resources). Here, the uplink grant can be a single-UE grant, or can be an uplink group grant for a plurality of UEs. As yet another example, the uplink group grant can be used by UEs that obtain different random access message processing results (e.g., for a certain UE, decoding of the payload of msgA fails, while for a second UE, decoding of the payload of msgA succeeds, where the second UE needs to transmit additional uplink data). As described below, various aspects of the uplink grant design described herein provide higher spectral efficiency and reduced power consumption, while reducing the signaling management burden.

[0060] Figures 3A - 3C are diagrams illustrating examples associated with random access responses for two-step random access procedures according to various aspects of the present disclosure. For the purposes of the examples shown in Figures 3A - 3C, a UE (e.g., UE 120) is configured to use a two-step RACH procedure associated with a base station (e.g., base station 110).

[0061] Figure 3A is a diagram of example 300, where the uplink grant included in the shifted random access response is an uplink group grant associated with a plurality of UEs including the UE. As shown in Figure 3A and by reference numerals 302 and 304, the UE can transmit a preamble signal of a random access message (msgA preamble signal) associated with the two-step RACH procedure and a payload of the random access message (msgA payload) associated with the two-step RACH procedure.

[0062] As shown by reference numeral 306, the base station detects the preamble signal of the random access message. However, as shown by reference numeral 308, the base station fails to decode the payload of the random access message.

[0063] As shown by element symbol 310, at least in part based on detecting a preamble signal and failing to decode the payload, the base station may transmit a random access response associated with a two-step random access procedure, the random access response including uplink group grants for a plurality of UEs including the UE. In other words, the base station may transmit a msgB with a shifted random access response, the shifted random access response including uplink group grants. In some aspects, the shifted random access response may include a set of K (K≥1) RAPIDs, each RAPID associated with a corresponding one of the K UEs, where preamble signals were detected for the K UEs but the payloads were not successfully decoded.

[0064] An uplink group grant is an uplink grant for a plurality of UEs, which means that the plurality of UEs may share the resources of the uplink grant associated with an additional uplink transmission. In some aspects, the uplink group grant may indicate a resource set and a modulation and coding scheme (MCS) (e.g., the resource set and MCS to be used by the UEs for transmitting msg3) to be used by the plurality of UEs for transmitting other random access messages.

[0065] In some aspects, the demodulation reference signal (DMRS) resource configuration (e.g., ports and / or sequences) for the plurality of UEs may be explicitly indicated in the uplink group grant. Alternatively, the DMRS resource configuration for the plurality of UEs may be implicitly indicated via a mapping rule (e.g., a mapping rule between a preamble signal resource index and a DMRS resource index configured by the base station for the plurality of UEs, where the preamble signal resource index may include both a random access channel (RACH) occasion (RO) and a sequence, and the DMRS resource index may include both an antenna port and a sequence).

[0066] In some aspects, the base station may transmit a timing advance (TA) command associated with the UE, and a temporary cell radio network temporary identifier (TC-RNTI) associated with the UE, separately from the uplink group grant (e.g., such that each of the plurality of UEs may receive a corresponding TA command and TC-RNTI).

[0067] In some aspects, the uplink group grant may be the only uplink group grant included in the random access response. In other words, in some cases, the random access response transmitted by the base station may include a single uplink group grant for a plurality of UEs.

[0068] Alternatively, in some aspects, the random access response may include multiple uplink group grants. For example, the uplink group grant may be a first uplink group grant, and the plurality of UEs may be a first plurality of UEs for which a preamble signal was detected but the payload was not successfully decoded. In this instance, the random access response may also include a second uplink group grant associated with a second plurality of UEs (e.g., a separate uplink group grant for another plurality of UEs for which a preamble signal was detected but the payload was not successfully decoded). In some aspects, the base station may partition the group of UEs into the first plurality of UEs and the second plurality of UEs based at least in part on, for example, the proximity of the timing offset associated with a group of UEs or the UE state associated with the group of UEs (e.g., derived from rules for msgA preamble signals, RO selection, etc.).

[0069] In some aspects, the random access response may also include a single-UE uplink grant for another UE. For example, the random access response may include uplink group grants for a plurality of UEs and may also include a single-UE grant for another UE (e.g., a UE not included in the plurality of UEs).

[0070] As shown in FIG. 3A and further indicated by reference numeral 312, a UE may receive a random access response that includes uplink group grants for a plurality of UEs and may transmit uplink communications (e.g., msg3) based at least in part on the uplink group grants. Here, the UE may adjust the timing offset independently (e.g., based on a TA command associated with the UE) and scramble the PUSCH bits independently, but may use the resource set and MCS indicated by the uplink group grant (i.e., the same resource set and the same MCS as used by other UEs in the plurality of UEs).

[0071] Here, the use of uplink group grants improves spectral efficiency because multiple UEs may use the same resource set and MCS associated with transmitting uplink communications during a two-step RACH procedure. In addition, by using uplink group grants (instead of multiple single-UE grants), the power consumption at the base station is reduced and the signaling management burden is reduced.

[0072] FIG. 3B is a diagram of Example 320, where uplink grant is included in a successful random access response. As shown in FIG. 3B and by reference numerals 322 and 324, a UE may transmit a preamble signal (msgA preamble) of a random access message associated with a two-step RACH procedure and a payload (msgA payload) of the random access message associated with the two-step RACH procedure. As indicated by reference numeral 324, the payload of the random access message may include an indication that the UE needs to transmit additional uplink data (e.g., in addition to the uplink data included in the payload, the UE also has uplink data ready for transmission). In some aspects, the indication may be in the form of a buffer status report (BSR) included in the payload of the random access message, a scheduling request (SR) included in the payload of the random access message, etc.

[0073] As shown by reference numeral 326, the base station detects the preamble signal of the random access message. As shown by reference numeral 328, the base station decodes the payload of the random access message. As further shown by reference numeral 328, the base station may determine that the UE needs to transmit additional uplink data. In some aspects, the base station may determine that the UE needs to transmit additional uplink data based at least in part on an indication in the payload of the random access message.

[0074] As shown by reference numeral 330, based at least in part on the determination that the UE needs to transmit additional uplink data, the base station may transmit a random access response associated with the two-step random access procedure, the random access response including an uplink grant for the UE. In other words, the base station may transmit a successful random access response including an uplink grant.

[0075] In some aspects, the uplink grant may be a single-UE uplink grant for the UE (e.g., an uplink grant dedicated to the UE). In this case, in some aspects, the random access response may further include an uplink group grant for a plurality of UEs other than the UE (e.g., for a plurality of other UEs whose payloads are successfully decoded, where each UE in the plurality of UEs needs to transmit additional uplink data).

[0076] In some aspects, the uplink grant may be an uplink group grant for a plurality of UEs including the UE (e.g., for a plurality of UEs for which payload decoding is successful, where each UE in the plurality of UEs needs to transmit additional uplink data). In some aspects, the classification of the plurality of UEs may be at least partially based on reference signal received power (RSRP) measurements, channel state information (CSI) reports, beam management, quality of service (QoS) handling, positioning-related measurements, etc. In other words, in some aspects, the base station may classify the UEs as being associated with a given uplink group grant at least partially based on one or more measurements and / or characteristics determined from the payload of the random access message transmitted by each UE. The information carried and / or indicated by the uplink group grant is similar to the information described above in connection with FIG. 3A. In some aspects, the uplink group grant may be the only uplink group grant included in the random access response, or may be one of a plurality of uplink group grants included in the random access response. Additionally, in some aspects, in the case where the uplink grant is an uplink group grant, the random access response may further include a single UE uplink grant for another UE.

[0077] As further shown in FIG. 3B by element symbol 332, the UE may receive a random access response including an uplink grant for the UE and may transmit uplink communication (e.g., including additional uplink data) at least partially based on the uplink grant. Here, if the uplink grant is an uplink group grant, the UE may independently adjust the timing offset (e.g., based on a TA command associated with the UE) and scramble the PUSCH bits, but may use the resource set and MCS indicated by the uplink group grant (i.e., the same resource set and the same MCS as other UEs in the plurality of UEs).

[0078] Here, the use of the uplink grant in the successful random access response may improve spectral efficiency because multiple UEs may use the same resource set and MCS associated with transmitting uplink communication. Additionally, by providing the uplink grant in the successful random access response (instead of waiting for the UE to provide an explicit request for uplink resources), the power consumption at the UE and the base station is reduced, and the signaling management burden is decreased.

[0079] FIG. 3C is a diagram of Example 340, where the uplink grant included in the shifted random access response is an uplink group grant associated with a plurality of UEs, the plurality of UEs including UEs with decoding failures for the payloads of their random access messages and UEs with decoding successes for the payloads of their random access messages.

[0080] In some aspects, the base station can identify a plurality of UEs to which an uplink group grant is to be transmitted, associated with a two-step random access procedure, where the plurality of UEs includes a first UE with a decoding failure for the payload of its first random access message and a second UE with a decoding success for the payload of its second random access message.

[0081] For example, as shown by reference numerals 342 and 344, a first UE (UE1) can transmit a preamble signal of a first random access message and the payload of the first random access message. As shown by reference numeral 346, the base station detects the preamble signal of the first random access message. However, as shown by reference numeral 348, the base station fails to decode the payload of the first random access message. In addition, as shown by reference numerals 350 and 352, a second UE (UE2) can transmit a preamble signal of a second random access message and the payload of the second random access message. As shown by reference numeral 354, the base station detects the preamble signal of the second random access message, and as shown by reference numeral 356, successfully decodes the payload of the second random access message. In this example, the base station has identified a plurality of UEs to which an uplink group grant is to be transmitted, associated with a two-step random access procedure, where the plurality of UEs includes the first UE (e.g., UE1 with a decoding failure for the payload of its first random access message) and the second UE (e.g., UE2 with a decoding success for the payload of its second random access message).

[0082] As shown by reference numeral 358, at least in part based on identifying the plurality of UEs, the base station can transmit a random access response associated with a two-step random access procedure, the random access response including an uplink group grant for a plurality of UEs including the first UE and the second UE. It is noted that in such a case, the uplink group grant will be shared by a plurality of UEs with different msgA processing results. In other words, the uplink group grant can be shared by a first UE with a decoding failure for its payload (e.g., in order to transmit msg3) and a second UE with a decoding success for its payload (e.g., in order to transmit additional uplink communications). Here, a single uplink group grant is needed, rather than multiple independent uplink grants in the shifted random access response and the successful random access response.

[0083] In some aspects, the base station may transmit a random access response in a resource set that is unrelated to the resources corresponding to the shifted random access response and the resources corresponding to the successful random access response, and a plurality of UEs may receive the random access response. Alternatively, in some aspects, the base station may transmit an uplink group grant in a resource set shared by the shifted random access response and the successful random access response, and a plurality of UEs may receive the uplink group grant.

[0084] In some aspects, the information carried and / or indicated by the uplink group grant may be similar to the information described above in connection with FIG. 3A. In some aspects, the uplink group grant may be the only uplink group grant included in the random access response, or may be one of a plurality of uplink group grants included in the random access response. Additionally, in some aspects, the random access response may also include a single-UE uplink grant for another UE.

[0085] Similar to the above manner, the first UE and the second UE may receive a random access response including an uplink group grant, and may transmit their respective uplink communications (e.g., including msg3 and additional uplink data) at least partially based on the uplink group grant.

[0086] Here, the use of the uplink group grant improves spectral efficiency because multiple UEs can use the same resource set and MCS associated with transmitting uplink communications during the two-step RACH procedure. Additionally, by using the uplink group grant (instead of multiple single-UE grants), the power consumption at the base station is reduced, and the signaling management burden is reduced. Further, by providing the uplink group grant in the random access response to the UE that successfully decoded its payload (instead of waiting for the UE to provide an explicit request for uplink resources), the power consumption at the UE and the base station is reduced, and the signaling management burden is reduced.

[0087] As indicated in the above examples, the base station may construct one or more uplink group grants for two-step RACH UEs for which it has detected their preamble or payload. In some aspects, the status of the uplink group grant included in the random access response (e.g., msgB) may include information identifying the number of group grants, information identifying the type of group grant, an indication of the type of group grant, etc. In some aspects, the indication of the type of group grant may be at least partially based on a bitmap.

[0088] In some aspects, the random access response may include a random access response PDCCH (e.g., msgB PDCCH) and a random access response PDSCH (e.g., msgB PDSCH) (including DMRS).

[0089] In some aspects, the random access response PDCCH may include downlink control information (DCI) with a cyclic redundancy check (CRC) attached. In some aspects, the CRC may be masked with a group RNTI such as RA-RNTI. In some aspects, the random access response PDCCH may be configured in a common search space that will be monitored by a set of two-step RACH UEs sharing the same RACH occasion used for the transmission of random access messages (e.g., msgA). In some aspects, the DCI may carry resource allocation for the random access response PDSCH. In some aspects, the DCI may carry an early indication of the type of uplink group allowed, such as uplink group allowance in FallbackRAR, uplink group allowance in SuccessRAR, shared uplink group allowance, etc.

[0090] In some aspects, the random access response PDSCH may include a MAC packet data unit (PDU). In some aspects, the MAC PDU may carry at least FallbackRAR and SuccessRAR, where the uplink group allowance may be included in one or more other fields of FallbackRAR, SuccessRAR, or the MAC PDU. In some aspects, the uplink group allowance field may at least include the common time-frequency resource allocation for subsequent uplink transmissions (e.g., PUSCH transmissions). In some aspects, the uplink group allowance field also includes MCS, PUSCH jump flag, DMRS resource configuration, and / or common information for power control and beam management.

[0091] As described above, FIGS. 3A - 3C are provided as examples. Other examples may be different from the examples described with respect to FIGS. 3A - 3C.

[0092] FIG. 4 is a diagram illustrating an exemplary process 400, such as may be performed by a base station, in accordance with various aspects of the present disclosure. Exemplary process 400 is an example in which a base station (e.g., base station 110, etc.) performs operations associated with a random access response for a two-step RACH procedure.

[0093] As shown in FIG. 4, in some aspects, process 400 may include detecting a preamble signal of a random access message associated with a two-step random access procedure (block 410). For example, as described above, a base station (e.g., using receive processor 238, controller / processor 240, memory 242, etc.) may detect a preamble signal of a random access message associated with a two-step random access procedure. In some aspects, the random access message is received from a UE (e.g., UE 120).

[0094] As further shown in FIG. 4, in some aspects, process 400 may include processing the payload of the random access message, where the result of processing the payload is successfully decoding the payload or failing to decode the payload (block 420). For example, as described above, a base station (e.g., using receive processor 238, controller / processor 240, memory 242, etc.) may process the payload of the random access message. In some aspects, the result of processing the payload is successfully decoding the payload or failing to decode the payload.

[0095] As further shown in FIG. 4, in some aspects, process 400 may include transmitting a random access response associated with the two-step random access procedure based at least in part on detecting the preamble signal and the result of processing the payload, where the random access response includes an uplink group grant for a plurality of UEs including the UE and an indication of the type of the uplink group grant (block 430). For example, as described above, a base station (e.g., using transmit processor 220, receive processor 238, controller / processor 240, memory 242, etc.) may transmit a random access response associated with the two-step random access procedure based at least in part on detecting the preamble signal and the result of processing the payload. In some aspects, the random access response includes an uplink group grant for a plurality of UEs including the UE and an indication of the type of the uplink group grant. In some aspects, the preamble signal transmissions of the plurality of UEs share a time-frequency opportunity.

[0096] Process 400 may include additional aspects, such as any single aspect described below and / or in combination with one or more other process descriptions elsewhere in this document, or any combination of such aspects.

[0097] In a first aspect, when the result of processing the payload of the random access message is failing to decode the payload, an uplink group grant is included in the random access response based at least in part on the failure to decode the payload.

[0098] In a second aspect, alone or in combination with the first aspect, the uplink group grant is included in the shifted random access response.

[0099] In a third aspect, alone or in combination with one or more of the first and second aspects, the UE is included in the plurality of UEs at least in part based on a timing offset associated with the UE or the UE state of the UE. For example, the group of UEs can be divided into two or more groups of the plurality of UEs including the plurality of UEs therein at least in part based on the proximity of the timing offset associated with a group of UEs or the UE state associated with the group of UEs.

[0100] In a fourth aspect, alone or in combination with one or more of the first to third aspects, the uplink group grant indicates a shared set of time-frequency resources, a modulation and coding scheme (MCS), shared information for power control or beam management, and a physical uplink shared channel (PUSCH) jump flag to be used by the plurality of UEs for transmitting other random access messages.

[0101] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, a demodulation reference signal (DMRS) resource configuration for the plurality of UEs is explicitly indicated in the uplink group grant.

[0102] In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, a demodulation reference signal (DMRS) resource configuration for the plurality of UEs is implicitly indicated via a mapping rule associated with a preamble signal resource index and a DMRS resource index configured by the base station for the plurality of UEs.

[0103] In a seventh aspect, alone or in combination with one or more of the first to sixth aspects, a timing advance (TA) command associated with the UE and a temporary cell radio network temporary identifier (TC-RNTI) associated with the UE are transmitted separately from the uplink group grant.

[0104] In an eighth aspect, alone or in combination with one or more of the first to seventh aspects, the uplink group grant is the only uplink group grant included in the random access response.

[0105] In a ninth aspect, alone or in combination with one or more of the first to eighth aspects, the uplink group grant is one of the plurality of uplink group grants included in the random access response.

[0106] In a tenth aspect, either alone or in combination with one or more of the first to ninth aspects, the random access response also includes a single UE uplink grant for another UE.

[0107] In an eleventh aspect, either alone or in combination with one or more of the first to tenth aspects, the result of processing the payload of the random access message is successful decoding of the payload. Here, the base station can determine that the UE needs to transmit additional uplink data based at least in part on an indication in the payload.

[0108] In a twelfth aspect, either alone or in combination with one or more of the first to eleventh aspects, an uplink group grant is included in the successful random access response.

[0109] In a thirteenth aspect, either alone or in combination with one or more of the first to twelfth aspects, the indication is provided via a buffer status report (BSR).

[0110] In a fourteenth aspect, either alone or in combination with one or more of the first to thirteenth aspects, the indication is provided via a scheduling request (SR).

[0111] In a fifteenth aspect, either alone or in combination with one or more of the first to fourteenth aspects, the UE is classified into the plurality of UEs based at least in part on at least one of the following: reference signal received power (RSRP) measurement, channel state information (CSI) report, beam management, quality of service (QoS) handling, or positioning-related measurement.

[0112] In a sixteenth aspect, either alone or in combination with one or more of the first to fifteenth aspects, the uplink group grant is transmitted in a resource independent of the resources corresponding to the shifted random access response and the resources corresponding to the successful random access response.

[0113] In a seventeenth aspect, either alone or in combination with one or more of the first to sixteenth aspects, the uplink group grant is transmitted in a resource set shared by the shifted random access response and the successful random access response.

[0114] In an eighteenth aspect, either alone or in combination with one or more of the first to seventeenth aspects, an indication of the type of the uplink group grant is transmitted in a downlink control information (DCI) field of a physical downlink control channel (PDCCH) of the random access response entity.

[0115] In a nineteenth aspect, alone or in combination with one or more of the first to eighteenth aspects, the indication of the type of uplink group allowed is at least partially based on a bit map.

[0116] In a twentieth aspect, alone or in combination with one or more of the first to nineteenth aspects, DCI is associated with a cyclic redundancy check (CRC). Here, the CRC can be masked by a group radio network temporary identifier (RNTI).

[0117] In a twenty - first aspect, alone or in combination with one or more of the first to twentieth aspects, a random access response PDCCH is transmitted in a common search space.

[0118] Although FIG. 4 illustrates exemplary blocks of process 400, in some aspects, process 400 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks compared to those shown in FIG. 4. Additionally or alternatively, two or more blocks of process 400 may be executed concurrently.

[0119] FIG. 5 is a diagram illustrating an exemplary process 500, such as may be performed by a UE, in accordance with various aspects of the present disclosure. Exemplary process 500 is an example in which a UE (e.g., UE 120, etc.) performs operations associated with a random access response for a two - step RACH procedure.

[0120] As shown in FIG. 5, in some aspects, process 500 may include transmitting a preamble signal and a payload of a random access message associated with a two - step random access procedure (block 510). For example, as described above, a UE (e.g., using a transmission processor 264, a controller / processor 280, a memory 282, etc.) may transmit a preamble signal and a payload of a random access message associated with a two - step random access procedure.

[0121] As further shown in FIG. 5, in some aspects, process 500 may include receiving a random access response associated with a two-step random access procedure, the random access response including an uplink group grant for a plurality of UEs including the UE and an indication of the type of the uplink group grant (block 520). For example, as described above, a UE (e.g., using receive processor 258, controller / processor 280, memory 282, etc.) may receive a random access response associated with a two-step random access procedure, the random access response including an uplink group grant for a plurality of UEs including the UE and an indication of the type of the uplink group grant.

[0122] As further shown in FIG. 5, in some aspects, process 500 may include transmitting uplink communication on a shared time-frequency resource set based at least in part on the uplink group grant (block 530). For example, as described above, a UE (e.g., using transmit processor 264, controller / processor 280, memory 282, etc.) may transmit uplink communication on a shared time-frequency resource set based at least in part on the uplink group grant.

[0123] Process 500 may include additional aspects, such as any single aspect described below and / or in combination with one or more other processes described elsewhere in this document, or any combination of such aspects.

[0124] In a first aspect, the uplink group grant is included in the random access response at least in part based on the base station's failure to decode the payload.

[0125] In a second aspect, alone or in combination with the first aspect, the uplink group grant is included in a shifted random access response.

[0126] In a third aspect, alone or in combination with one or more of the first and second aspects, the UE is included in the plurality of UEs at least in part based on a timing offset associated with the UE or the UE state of the UE.

[0127] In a fourth aspect, alone or in combination with one or more of the first to third aspects, the uplink group grant indicates a shared set of time-frequency resources, a modulation and coding scheme (MCS), shared information for power control or beam management, and a physical uplink shared channel (PUSCH) jump flag to be used by the plurality of UEs for transmitting other random access messages.

[0128] In a fifth aspect, either alone or in combination with one or more of the first to fourth aspects, a demodulation reference signal (DMRS) resource configuration for the plurality of UEs is explicitly indicated in the uplink group grant.

[0129] In a sixth aspect, either alone or in combination with one or more of the first to fifth aspects, a demodulation reference signal (DMRS) resource configuration for the plurality of UEs is implicitly indicated via a mapping rule associated with a preamble signal resource index and a DMRS resource index configured by the base station for the plurality of UEs.

[0130] In a seventh aspect, either alone or in combination with one or more of the first to sixth aspects, a timing advance (TA) command associated with a UE and a temporary cell radio network temporary identifier (TC-RNTI) associated with the UE are received separately from the uplink group grant.

[0131] In an eighth aspect, either alone or in combination with one or more of the first to seventh aspects, the uplink group grant is the only uplink group grant included in the random access response.

[0132] In a ninth aspect, either alone or in combination with one or more of the first to eighth aspects, the uplink group grant is one of a plurality of uplink group grants included in the random access response.

[0133] In a tenth aspect, either alone or in combination with one or more of the first to ninth aspects, the random access response also includes a single-UE uplink grant for another UE.

[0134] In an eleventh aspect, either alone or in combination with one or more of the first to tenth aspects, an indication that the UE needs to transmit additional uplink data is included in the payload.

[0135] In a twelfth aspect, either alone or in combination with one or more of the first to eleventh aspects, the uplink group grant is included in a successful random access response.

[0136] In a thirteenth aspect, either alone or in combination with one or more of the first to twelfth aspects, the indication is provided via a buffer status report (BSR).

[0137] In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the indication is provided via a scheduling request (SR).

[0138] In a fifteenth aspect, alone or in combination with one or more of the first through fourteenth aspects, the UE is classified into the plurality of UEs based at least in part on at least one of the following: reference signal received power (RSRP) measurements, channel state information (CSI) reports, beam management, quality of service (QoS) handling, or positioning-related measurements.

[0139] In a sixteenth aspect, alone or in combination with one or more of the first through fifteenth aspects, an uplink group grant is received in a resource independent of the resources corresponding to a shifted random access response and the resources corresponding to a successful random access response.

[0140] In a seventeenth aspect, alone or in combination with one or more of the first through sixteenth aspects, an uplink group grant is received in a resource set shared by a shifted random access response and a successful random access response.

[0141] In an eighteenth aspect, alone or in combination with one or more of the first through seventeenth aspects, an indication of the type of uplink group grant is received in a downlink control information (DCI) field of a random access response physical downlink control channel (PDCCH) based at least in part on monitoring of the random access response PDCCH.

[0142] In a nineteenth aspect, alone or in combination with one or more of the first through eighteenth aspects, the DCI is associated with a cyclic redundancy check (CRC). Here, a group radio network temporary identifier (RNTI) can be used to unmask the CRC.

[0143] In a twentieth aspect, alone or in combination with one or more of the first through nineteenth aspects, the DCI is decoded to determine a resource allocation for a random access response physical downlink shared channel (PDSCH). Here, an indication of the type of uplink group grant can be carried in the random access response PDSCH.

[0144] In a twenty-first aspect, alone or in combination with one or more of the first through twentieth aspects, the random access response and the uplink group grant are decoded.

[0145] In a twenty-second aspect, alone or in combination with one or more of the first to twenty-first aspects, timing advance (TA), modulation and coding scheme (MCS), power control, beam management, and time-frequency resource allocation are applied in connection with transmitting uplink communications.

[0146] Although FIG. 5 illustrates exemplary blocks of process 500, in some aspects, process 500 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks compared to those shown in FIG. 5. Additionally or alternatively, two or more blocks of process 500 may be executed concurrently.

[0147] FIG. 6 is a diagram illustrating an exemplary process 600, such as may be performed by a base station, in accordance with various aspects of the present disclosure. Exemplary process 600 is an example in which a base station (e.g., base station 110, etc.) performs operations associated with design considerations for a random access response for a two-step random access procedure.

[0148] As shown in FIG. 6, in some aspects, process 600 may include constructing an uplink group grant for a plurality of UEs performing a two-step random access procedure, where a preamble signal or payload of a random access message provided by the plurality of UEs has been detected by the base station (block 610). For example, as described above, a base station (e.g., using transmission processor 220, reception processor 238, controller / processor 240, memory 242, etc.) may construct an uplink group grant for a plurality of UEs (e.g., UE 120) performing a two-step random access procedure. In some aspects, the base station has detected a preamble signal or payload of a random access message provided by the plurality of UEs.

[0149] As further shown in FIG. 6, in some aspects, process 600 may include transmitting a random access response associated with a two-step random access procedure, where the random access response includes an uplink group grant and an indication of the type of uplink grant (block 620). For example, as described above, a base station (e.g., using transmission processor 220, controller / processor 240, memory 242, etc.) may transmit a random access response associated with a two-step random access procedure. In some aspects, the random access response includes an uplink group grant and an indication of the type of uplink group grant.

[0150] Process 600 may include additional aspects, such as any single aspect described below and / or in combination with one or more of the other process descriptions elsewhere in this document, or any combination of such aspects.

[0151] In a first aspect, the random access response includes an uplink group grant status that includes information identifying the number of uplink group grants included in the random access response, or an indication of the type of uplink group grant, or at least one of them.

[0152] In a second aspect, alone or in combination with the first aspect, an indication of the type of uplink group grant is transmitted in a DCI field of a random access response PDCCH.

[0153] In a third aspect, alone or in combination with one or more of the first and second aspects, the indication of the type of uplink group grant is at least partially based on a bit map.

[0154] In a fourth aspect, alone or in combination with one or more of the first to third aspects, a DCI is associated with a CRC, and the CRC is masked by a group RNTI.

[0155] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, a random access response PDCCH is transmitted in a common search space.

[0156] Although FIG. 6 illustrates exemplary blocks of process 600, in some aspects, process 600 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks compared to those shown in FIG. 6. Additionally or alternatively, two or more blocks of process 600 may be executed concurrently.

[0157] FIG. 7 is a diagram illustrating an exemplary process 700, such as may be performed by a UE, in accordance with various aspects of the present disclosure. Exemplary process 700 is an example in which a UE (e.g., UE 120, etc.) performs operations associated with design considerations for a random access response for a two-step random access procedure.

[0158] As shown in FIG. 7, in some aspects, process 700 may include transmitting a preamble signal and a payload of a random access message associated with a two-step random access procedure (block 710). For example, as described above, a UE (e.g., using a transmission processor 264, a controller / processor 280, a memory 282, etc.) may transmit a preamble signal and a payload of a random access message associated with a two-step random access procedure.

[0159] As further shown in FIG. 7, in some aspects, process 700 may include receiving a random access response associated with a two-step random access procedure after transmitting a preamble signal and payload of a random access message, where the random access response includes uplink group grants for a plurality of UEs including the UE, and where the random access response includes an indication of the type of uplink group grant (block 720). For example, as described above, a UE (e.g., using receive processor 258, controller / processor 280, memory 282, etc.) may receive a random access response associated with a two-step random access procedure after transmitting a preamble signal and payload of a random access message. In some aspects, the random access response includes uplink group grants for a plurality of UEs including the UE, and where the random access response includes an indication of the type of uplink group grant.

[0160] Process 700 may include additional aspects, such as any single aspect described below and / or in combination with one or more other process descriptions elsewhere in this document, or any combination of such aspects.

[0161] In a first aspect, the random access response includes a status of the uplink group grant, the status including information identifying the number of uplink group grants included in the random access response, or at least one of an indication of the type of uplink group grant.

[0162] In a second aspect, alone or in combination with the first aspect, an indication of the type of uplink group grant is received in a DCI field of a random access response PDCCH.

[0163] In a third aspect, alone or in combination with one or more of the first and second aspects, the indication of the type of uplink group grant is at least partially based on a bit map.

[0164] In a fourth aspect, alone or in combination with one or more of the first to third aspects, where the DCI is associated with a CRC, and where the CRC is masked by a group RNTI.

[0165] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, the random access response PDCCH is received in a common search space.

[0166] Although FIG. 7 illustrates exemplary blocks of process 700, in some aspects, process 700 may include additional blocks, fewer blocks, different blocks, or blocks arranged differently compared to those shown in FIG. 7. Additionally or alternatively, two or more blocks of process 700 may execute concurrently.

[0167] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit aspects to the precise forms disclosed. Modifications and variations are possible in light of the above disclosure, or may be acquired from practice of such aspects.

[0168] As used herein, the term "element" is intended to be broadly construed as hardware, firmware, and / or a combination of hardware and software. As used herein, a processor is implemented as hardware, firmware, and / or a combination of hardware and software.

[0169] As used herein, depending on context, meeting a threshold may mean that a value is greater than a threshold, greater than or equal to a threshold, less than a threshold, less than or equal to a threshold, equal to a threshold, not equal to a threshold, and so forth.

[0170] It will be apparent that the systems and / or methods described herein may be implemented in different forms of hardware, firmware, and / or combinations of hardware and software. The actual special control hardware or software code used to implement such systems and / or methods does not limit such aspects. Thus, the operations and behaviors of the systems and / or methods are described herein without reference to specific software code - it should be understood that software and hardware can be designed to implement the systems and / or methods at least in part based on the description herein.

[0171] Although specific combinations of features are recited in the claims and / or disclosed in the specification, such combinations are not intended to limit the disclosure of possible aspects. In fact, many such 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 each aspect includes the combination of each dependent claim with every other claim in the set of claims. The phrase "at least one" in reference to a list of items refers to any combination of those items, including a single member. 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).

[0172] None of the elements, acts, or instructions used herein should be construed as critical or essential unless expressly stated as such. Additionally, 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." Further, as used herein, the terms "set" and "group" are intended to include one or more items (e.g., related items, unrelated items, combinations of related and unrelated items, etc.) and may be used interchangeably with "one or more." Where only one item is intended, the phrase "only one" or similar language is used. Additionally, as used herein, the terms "has," "have," "having," etc. are intended to be open-ended terms. Further, unless expressly stated otherwise, the phrase "based on" is intended to mean "at least partially based on."

[0173] 100: Wireless network 102a: Macrophage 102b: Pico cell 102c: Femto cell 110: BS 110a: BS 110b: BS 110c: BS 110d: Relay station 120: UE 120a: UE 120b: UE 120c: UE 120d: UE 120e: UE 130: Network controller 200: Design 212: Data source 220: Transmission processor 230: Transmission (TX) multiple-input multiple-output (MIMO) processor 232a: Modulator / demodulator 232t: Modulator / demodulator 234a: Antenna 234t: Antenna 236: MIMO detector 238: Reception processor 239: Data slot 240: Controller / processor 242: Memory 244: Communication unit 246: Scheduler 252a: Antenna 252r: Antenna 254a: Demodulator / Modulator 254r: Demodulator / Modulator 256: MIMO Detector 258: Receiver Processor 260: Data Slot 262: Data Source 264: Transmission Processor 266: TX MIMO Processor 280: Controller / Processor 282: Memory 290: Controller / Processor 292: Memory 294: Communication unit 300: Instance 302: Component Symbol 304: Component Symbol 306: Component Symbol 308: Component Symbol 310: Component Symbol 312: Component Symbol 320: Instance 322: Component Symbol 324: Component Symbol 326: Component Symbol 328: Component Symbol 330: Component Symbol 332: Component Symbol 340: Instance 342: Component Symbol 344: Component Symbol 346: Component Symbol 348: Component Symbol 350: Component Symbol 352: Component Symbol 354: Component Symbol 356: Component Symbol 358: Component Symbol 400: Process 410: Block 420: Block 430: Block 500: Process 510: Block 520: Block 530: Block 600: Process 610: Block 620: Block 700: Process 710: Block 720: Block

[0174] Domestic deposit information (Please note in the order of deposit institution, date, and number) None Foreign deposit information (Please note in the order of deposit country, institution, date, and number) None

Claims

1. A method for wireless communication at a user equipment (UE), comprising the steps of: transmitting a preamble signal and a payload of a random access message associated with a two-step random access procedure; receiving a random access response associated with the two-step random access procedure, the random access response comprising: The uplink permission is defined for a plurality of UEs including the UE, a state of the uplink permission, and an indication of a type of the uplink permission, wherein the state includes: information identifying a number of uplink permissions included in the random access response, wherein the indication of the type of the uplink permission may indicate that the uplink permission is used for one of the following: a shifted random access response, a successful random access response, or a shared uplink permission, wherein the uplink permission is transmitted in a resource set shared by the shifted random access response and the successful random access response; and at least in part based on the uplink permission, an uplink communication is transmitted on a shared time-frequency resource set.

2. The method as described in claim 1, including the uplink permission indication in the random access response indicating that a network entity failed to decode the payload.

3. The method as described in claim 2, wherein the uplink permission is included in the shifted random access response.

4. The method as described in claim 2, wherein the UE is included among the plurality of UEs based at least in part on a timing offset associated with the UE or a UE state of the UE.

5. The method as described in claim 1, wherein the uplink permission indication is comprised of a common set of time-frequency resources used by the plurality of UEs for transmitting other random access messages, a modulation and coding scheme (MCS), common information for power control or beam management, and a physical uplink shared channel (PUSCH) transition flag.

6. The method as described in claim 1, wherein a demodulation reference signal (DMRS) resource configuration for the plurality of UEs is explicitly indicated in the uplink permission.

7. The method as described in claim 1, wherein a demodulation reference signal (DMRS) resource configuration for the plurality of UEs is implicitly indicated via a mapping rule associated with a preceding signal resource index and a DMRS resource index configured by a network entity for the plurality of UEs.

8. The method as described in claim 1, wherein a timing advance (TA) command associated with the UE and a temporary cellular radio network temporary identifier (TC-RNTI) associated with the UE are received separately from the uplink permission.

9. The method as described in claim 1, wherein the uplink permission is a single uplink permission included in the random access response.

10. The method as described in claim 1, wherein the uplink permission is one of a plurality of uplink permissions included in the random access response.

11. The method as described in claim 1, wherein the random access response also includes: Uplink permission is granted for a single UE on another UE.

12. The method as described in claim 1, wherein the payload of the random access message includes an indication that the UE needs to transmit additional uplink data.

13. The method as described in request item 11, wherein the uplink permission is included in the successful random access response.

14. The method as described in claim 11, wherein the indication of the type permitted for the uplink is provided via a buffer status report (BSR).

15. The method as described in request item 11, wherein the indication of the type permitted for that uplink is provided via a scheduling request (SR).

16. The method as described in claim 11, wherein the UE is classified into the plurality of UEs based at least in part on at least one of the following: a reference signal received power (RSRP) measurement, a channel state information (CSI) report, beam management, quality of service (QoS) processing, or a location-related measurement.

17. A user equipment (UE) for wireless communication, comprising: One memory; and one or more processors coupled to the memory, which can operate individually or in any combination such that the UE: transmits a preamble signal and a payload of a random access message associated with a two-step random access procedure; receives a random access response associated with the two-step random access procedure, the random access response including: an uplink grant for a plurality of UEs including the UE, a state of the uplink grant, and an indication of a type of the uplink grant, wherein the state includes: information identifying a number of uplink grants included in the random access response, wherein the indication of the type of the uplink grant may indicate that the uplink grant is used for one of: a shifted random access response or a successful random access response, and wherein the uplink grant is transmitted in a resource set shared by the shifted random access response and the successful random access response; and transmits uplink communication on a shared time-frequency resource set at least in part based on the uplink grant.

18. The UE as described in request item 17, including the uplink permission indication in the random access response indicating that a network entity failed to decode the payload.

19. The UE as described in request item 17, wherein the uplink permission is included in the successful random access response.

20. A network entity for wireless communication, comprising: One memory; and one or more processors coupled to the memory, capable of operating individually or in any combination, such that the network entity: detects a preamble to a random access message associated with a two-step random access procedure, wherein the random access message is received from a user equipment (UE); processes a payload of the random access message, wherein a result of processing the payload is successful decoding of the payload or failure to decode the payload; and, at least in part based on the detection of the preamble and the result of processing the payload, transmits a random access response associated with the two-step random access procedure, wherein the random access response includes: an uplink permission for a plurality of UEs, including the UE, a state of the uplink permission, and an indication of a type of the uplink permission, wherein the state includes information identifying a number of uplink permissions included in the random access response. The indication of the type of uplink permission may indicate that the uplink permission is used for one of the following: a shifted random access response or a successful random access response, wherein the preceding signaling transmissions of the plurality of UEs share a time-frequency timing, and wherein the uplink permission is transmitted in a resource set shared by the shifted random access response and the successful random access response.

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