Methods, systems, and apparatuses are provided for listen-before-talk (LBT) mode for random access response (RAR) in a wireless communication system so that RAR indication of channel access type and cyclic prefix (CP) extension can be more efficient. A method of a User Equipment (UE) can comprise initiating a random access procedure, receiving a RAR, wherein the RAR comprises a channel access type indication, and determining whether to perform LBT for a Msg3 based on the channel access type indication in RAR.

A random access method, a base station, an UE and a device with a storage function are disclosed. The random access method includes: the base station receiving a first message transmitted by the UE, the first message including a preamble message and a signal message; decoding the preamble message and the signal message respectively; if the decoding of preamble message is succeeded, but the decoding of signal message fails, the base station transmits a second message to the UE, and storing the signal message of decoding failure, the second message configured to request the UE to retransmit the signal message; receiving the third message transmitted by the UE, the third message including the signal message; using a chase combine mechanism to decode the third message according to the stored signal message in the first message. The present disclosure save time and improve the efficiency of random access.

Provided are a method of adjusting uplink timing in a wireless communication system and an apparatus therefor. Specifically, a method for a user equipment to adjust uplink timing in a wireless communication system includes transmitting, to a base station, an uplink signal, receiving, from the base station, a timing advance (TA) command configured based on the uplink signal, and performing uplink transmission to the base station by applying a timing advance (TA) indicated by the TA command. The TA command may be interpreted based on subcarrier spacing of at least one frequency resource region to which the TA is to be applied.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive, from a base station, an indication of a monitoring window used by the base station to monitor for uplink transmissions from the UE. The UE may receive a control signal scheduling uplink resources for an uplink transmission by the UE on at least a first component carrier, the first component carrier in a first radio frequency spectrum band. The UE may reconfigure, in response to the received control signal, a first transmit chain of the UE from a second component carrier in a second radio frequency spectrum band to the first component carrier in the first radio frequency spectrum band for the uplink transmission. The UE may transmit, based at least in part on the indicated monitoring window and using at least the reconfigured first transmit chain, the uplink transmission on the first component carrier using the scheduled uplink resources.

Methods, systems, and devices for wireless communications are described. The described techniques may enhance coverage by supporting repetitions of a random access request. A user equipment (UE) may receive, from a network entity, a synchronization signal block (SSB) message. The UE may measure the SSB message in order to determine signal metric, such as reference signal received power (RSRP). Based on the RSRP of the SSB, the UE may determine to transmit a set of repetitions of a random access request. The UE may then monitor a resource of a downlink control channel for a random access response from the network entity.

In response to initiating a two-step random access (RA) procedure, a wireless device selects a first radio resource for transmission of a first message of the two-step RA procedure. Based on the first radio resource being invalid for the transmission of the first message, the wireless device switches from the two-step RA procedure to a four-step RA procedure and transmits, via a second radio resource, a preamble for the four-step RA procedure.

Embodiments of apparatus and method for random access are disclosed. In an example, a user equipment can include at least one processor and at least one memory including computer program code. The at least one memory and the computer program code can be configured to, with the at least one processor, cause the user equipment at least to send a trigger message and unique identifier in a first message from the user equipment to a network node. The at least one memory and the computer program code can also be configured to, with the at least one processor, cause the user equipment at least to receive an acknowledgement at the user equipment in a second message from the network node using the user equipment's unique identifier. Contention resolution for the user equipment can be concluded with only the first message and the second message.

Disclosed is a random access method and apparatus for a reduced capability user equipment in a wireless communication system. A method of performing random access by a UE in a wireless communication system according to an embodiment of the disclosure may include an operation of receiving random access-related configuration information from a base station; an operation of determining at least one of a RACH occasion (RO) group related to random access preamble transmission, one or more ROs, and a random access preamble group based on at least one of the random access-related configuration information, a UE type, and a repetition level; and an operation of transmitting one or more random access preambles in each of the one or more ROs.

An electronic device may transmit a communication request to a base station having an indication of a number of its receive branches and an indication of whether the communication request is designated as an urgent service fulfillment. The base station may delay a denial of the communication request until receiving the indication of whether the communication request is designated as using the urgent service fulfillment to reduce a likelihood of prematurely rejecting the communication request. The base station may also handover the communication request to a base station that supports the urgent service fulfillment. The base station may also be barred from transferring the user equipment to a frequency layer preferred by the base station when the communication request of the user equipment is designated as an urgent service fulfillment.

An RO indication method and apparatus, an RO determination method and apparatus, a storage medium, a base station and a terminal are provided. The RO indication method includes: determining RO configuration information which includes at least one of followings: an association relation between ROs and corresponding frequency resources where the ROs are located respectively, and an association relation between ROs and corresponding available preambles; and transmitting the RO configuration information to a UE. By the embodiments of the present disclosure, a network is able to determine an RO of a UE without considering influence caused by a maximum difference time of RTT and increasing an average waiting time for the UE to transmit a preamble.