A method and apparatus for accessing a NR cell in a mobile communication system are provided. Method for accessing a NR cell includes receiving in a first cell, by a terminal from a base station, a System Information Block1, monitoring, by the terminal, Physical Downlink Control Channel (PDCCH) for Random Access Response based at least in part on a specific ra-ResponseWindow and a specific ra-SearchSpace.

Terminal device receives a high-layer parameter and transmits a PRACH. The high-layer parameter indicates a set of PRACH occasions and a PRACH slot for transmission of the PRACH. In a case that a PRACH occasion in the set of PRACH occasions is allocated to a slot different from the PRACH slot, the PRACH occasion is dropped for transmission of the PRACH.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station, information that configures multiple random access channel (RACH) partitions, wherein the multiple RACH partitions are each associated with a respective combination of one or more RACH features. The UE may select, from the multiple RACH partitions, a RACH partition based at least in part on the UE satisfying one or more criteria for the combination of one or more RACH features associated with the RACH partition. The UE may transmit, to the base station, a preamble on physical RACH (PRACH) resources associated with the RACH partition to initiate a RACH procedure supporting the combination of one or more RACH features associated with the RACH partition. Numerous other aspects are described.

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.

Methods, systems, and devices for wireless communications are described. Generally, the described techniques provide for dynamically activating and deactivating random-access channel (RACH) occasions (ROs). A base station may configure one or more ROs on which a user equipment (UE) can transmit RACH messages. If higher priority signaling (e.g., downlink signaling or uplink signaling) overlaps in time with the ROs, the base station may deactivate one or more ROs to decrease the likelihood of self-interference or cross-link interference (e.g., if the UE or the base station are operating in full duplex mode). The base station may deactivate or activate ROs by indicating indices for one or more ROs, indices for one or more synchronization signal blocks (SSBs), a pattern of ROs, some or all ROs within a time period, some or all ROs until a next downlink signal updates the RO configuration or activates ROs, or any combination thereof.

Apparatuses, methods, and systems are disclosed for selecting a base unit in response to a handover condition being triggered. One method (1000) includes selecting (1002) a base unit of multiple base units for handover in response to at least one base unit of the multiple base units triggering a handover condition. The method (1000) includes transmitting (1004) a random access preamble to the base unit. The method (1000) includes performing (1006) a reestablishment procedure to establish communication with one base unit of the multiple base units in response to determining an inability to access each base unit of the multiple base units that meets the handover condition.

A method and an apparatus for maintenance of a bandwidth part. The method and apparatus resolve an issue of the prior art in which expiration of a bandwidth part deactivation timer during a random access process changes the bandwidth part to a default bandwidth part, such that data cannot be transmitted on an optimal bandwidth part, and may even cause an interruption of an ongoing data transmission, while also affecting an ongoing random access process. In embodiments of the present invention, a terminal keeps a current active bandwidth part unchanged during a random access process, and performs a restart operation of a bandwidth part deactivation timer after the random access process is successfully completed, such that a situation where a bandwidth part changes to a default bandwidth part does not occur during the random access process, thereby reducing interruption to ongoing data transmissions and reducing the impact on ongoing random access processes.

To avoid blocking node AC queues in the degraded MU EDCA mode due to regular OFDMA transmission of data from another AC queue in resource units provided by an AP, the present invention proposes to use a dedicated HEMUEDCATimer for each AC queue, in order for them to be able to exit the degraded MU EDCA mode independently of the other AC queues. In this respect, upon successfully transmitting data stored in two or more traffic queues, in each of one or more accessed resource units provided by the AP within one or more transmission opportunities, the node sets each traffic queue transmitting in the accessed resource unit in the degraded MU EDCA mode for a predetermined degrading duration counted down by a respective timer associated with the transmitting traffic queue. Next, upon expiry of any timer, the node switches back the associated traffic queue to the conventional EDCA mode.

A method and apparatus for sending uplink control information by a multi-mode wireless transmit/receive unit (WTRU) capable of operating on multiple component carriers of a plurality of radio access technologies (RATs) for multi-RAT operation are disclosed. The WTRU may generate uplink control information (UCI) pertaining to a first RAT and a second RAT, wherein the UCI may include a first plurality of hybrid automatic repeat request acknowledgements (HARQ-ACKs) pertaining to a plurality of downlink (DL) transmissions of the first RAT and a second plurality of HARQ-ACKs pertaining to a plurality of DL transmissions of the second RAT. The WTRU may multiplex at least part of the generated UCI pertaining to the first RAT and at least part of the generated UCI pertaining to the second RAT onto a physical channel on a component carrier of the second RAT.

A method and apparatus for cell update while in a Cell_FACH state are disclosed. After selecting a target cell, system information is read from the target cell including high speed downlink shared channel (HS-DSCH) common system information. A radio network temporary identity (RNTI) received in a source cell is cleared and a variable HS_DSCH_RECEPTION is set to TRUE. An HS-DSCH medium access control (MAC-hs) entity is configured based on the HS-DSCH common system information. High speed downlink packet access (HSDPA) transmission is then received in the target cell. A CELL UPDATE message is sent to notify of a cell change. The HSDPA transmission may be received using a common H-RNTI broadcast in the system information, a reserved H-RNTI as requested in a CELL UPDATE message, or a temporary identity which is a subset of a U-RNTI. The MAC-hs entity may be reset.