The present disclosure relates to a communication method and system for converging a 5.sup.th-Generation (5G) communication system for supporting higher data rates beyond a 4.sup.th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. Embodiments of the present invention provide a method for RACH re-attempt, a user equipment and a base station. The method comprises the steps of: by a base station, determining system configuration information and transmitting the system configuration information to a user equipment; and then, by the user equipment, transmitting a preamble sequence to perform random access, and if the random access is failed, performing RACH attempt according to the received RACH re-attempt configuration information to perform random access until a preset decision condition is satisfied. The embodiment of the present invention is used for RACH re-attempt when random access fails.

The present disclosure relates to the prioritization of devices taking part in a multi-user random access wireless communication. Based on some known conditions, devices that comply with the conditions are given preferential treatment during the random access period. The preferential treatment may refer to the eligible devices being allowed to access more resource units during the random access, or it may also mean faster access to the medium during the random access. By taking advantage of the methods described in the present disclosure, it is possible to assign higher priority to selected frame types and/or device categories in a multi-user random access wireless communication system.

A method, performed by a UE, for handling a two-step Random Access Channel (RACH) procedure, in a wireless communications network is provided. When a Random Access (RA) event is triggered the UE obtains a Physical Random Access Channel (PRACH) preamble corresponding to the RA event and/or a desired grant size, by randomly select a preamble mapping to a table entry providing a required size of a Physical Uplink Shared Channel (PUSCH) resource for the triggered RA event. The UE then obtains a grant from the PUSCH resource table based on the obtained PRACH preamble, which grant includes an indication of a PUSCH resource to use for a Msg 3 transmission in uplink.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may identify a maximum permissible exposure (MPE) event associated with a beam, determine that a physical uplink control channel (PUCCH) resource for transmitting a scheduling request is unavailable based at least in part on the identification of the MPE event associated with the beam, and initiate, based at least in part on the determination that the PUCCH resource is unavailable, a physical random access channel (PRACH) procedure to transmit an uplink message. Numerous other aspects are provided.

An apparatus and a method of wireless communication are provided. The method by a first next generation radio access network (NG-RAN) includes performing, by the first NG-RAN, a non-public network (NPN) cell identification on an access stratum (AS) level for downlink (DL), wherein performing, by the first NG-RAN, the NPN cell identification includes at least one of the followings: wherein a synchronization sequence for NPN can be transmitted in one or more synchronization signal blocks (SSBs) on an initial bandwidth part (BWP) by an NPN cell, wherein in a broadcasting system information on a DL BWP, an NPN identifier (ID) is present in an NPN access related information information element (IE), wherein the DL BWP for NPN is used to transmit an SSB and related system information, or wherein an access class permission is transmitted in system information on the DL BWP for NPN access allowance.

Various embodiments include methods for managing uplink timing advance configuration of wireless devices by a base station. A wireless device may send an initial access signal to a base station, receive from the base station an initial timing advance value responsive to the initial access signal, and send to the base station a next signal comprising a Physical Random Access Channel (PRACH) waveform via uplink (UL) receive (Rx) points over two or more beams. The base station may receive the next signal including the PRACH waveform via the two or more UL Rx points, select a refined timing advance value based on the signal, and send the refined timing advance value to the wireless device. The wireless device may receive the refined timing advance value and send a further signal to the base station via one of the UL Rx points using the refined timing advance.

A method performed by a user equipment (UE) includes initiating a Small Data Transmission (SDT) procedure for transmitting a first set of data packets to a base station (BS) via an uplink (UL) transmission, determining, while the UE is in a Radio Resource Control (RRC) Inactive state, whether to prioritize the UL transmission over a sidelink (SL) transmission when there is a conflict between the UL transmission and the SL transmission during the SDT procedure, where the SL transmission is for transmitting a second set of data packets to another UE.

A base station transmits first random access parameters, associated with beam failure recovery, and second random access parameters. The base station may receive, in response to a beam failure on a primary cell and based on the first random access parameters, a first random access preamble on a first BWP of the primary cell. The base station may receive, based on the second random access parameters and for consistent LBT failure recovery, a second random access preamble on a second BWP of the primary cell. Receiving the second random access preamble may be in response to stopping of a first random access process and switching of an active BWP of the primary cell from the first BWP to a second BWP. The stopping and the switching may be based on consistent LBT failure for the primary cell.

A method and an apparatus for performing a random access procedure in a wireless communication system are disclosed. A method of performing a random access procedure according to an embodiment of the present disclosure may include receiving, from a base station, configuration information for providing information needed for the terminal to access the wireless communication system via a non-terrestrial network (NTN) including a satellite, wherein the configuration information includes first information for adjusting an orbit of the satellite and second information on common timing advance (TA); and determining a terminal-specific TA value for the terminal based on a location of the terminal and the configuration information; and transmitting, to the base station, a first message for the random access procedure at a timing determined based on the terminal-specific TA value and a common TA value derived from the second information.

Methods, systems, and devices for wireless communication are described. A communication device may receive control signaling indicating a first set of resources for random access channel (RACH) occasions (ROs) and a second set of resources for communicating one or more indications of interference (e.g., crosslink interference (CLI)) associated with the ROs. The communication device may receive a reference signal (e.g., a sounding reference signal (SRS)) over at least one resource of the second set of resources. The communication device may perform a RACH procedure during an RO. The RO may be associated with the at least one resource and may be based on a signal parameter associated with the received reference signal satisfying a threshold (e.g., reference signal strength indicator (RSSI)).