A communication method and system for converging a fifth generation (5G) communication system for supporting higher data rates beyond a fourth generation (4G) system with a technology for internet of things (IoT) are provided. The communication method and system includes 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. A method by a terminal for transmitting a random access (RA) preamble is provided. The method includes receiving configuration information on RA resources associated with synchronization signal (SS) blocks from a base station, receiving one or more SS blocks from the base station, determining whether there is at least one suitable SS block for which contention free RA resources are configured amongst the one or more SS blocks based on the configuration information, selecting a suitable SS block for which contention free RA resources are configured if there is at least one suitable SS block for which contention free RA resources are configured amongst the one or more SS blocks, selecting a first RA preamble corresponding to the selected suitable SS block, and transmitting the first RA preamble to the base station.

A method performed by a wireless communication device for reducing handover delay, wherein the wireless communication device is arranged to operate in a cellular communication system and to operate in a cell using unlicensed spectrum. The method includes receiving a downlink, DL, signal from network node operating a neighbouring cell operating in the unlicensed spectrum, wherein the DL signal includes a discovery reference signal, DRS, subframe, storing data associated with the DRS subframe, receiving a handover command from a network node operating a serving cell where the neighbouring cell is a target cell, and performing a random access procedure for handover to the target cell. A device performing the method and a computer program for implementing the method are also disclosed.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may connect to a set of source cell groups (CGs). The UE may receive a target cell group setup information, the target cell group setup information being associated with a set of target CGs. The UE may connect to the set of target CGs based at least in part on the target cell group setup information during a handover from the set of source CGs to the set of target CGs. The UE may disconnect from the set of source CGs after connecting to the set of target CGs. Numerous other aspects are provided.

The present disclosure provides a cell handover method, a cell handover processing method, a terminal, and a network device, and the method includes: receiving a handover command sent by a first network node, where the handover command includes first slice information, the first slice information is used to indicate N slices, and N is a positive integer; and sending a random access request to a target slice of a target cell, where the target slice is one of the N slices.

The present application relates to devices and components including apparatus, systems, and methods to perform a switch of a TCI state from a serving cell to a neighbor cell. A UE determines whether the state of the neighbor cell is known or unknown and whether the neighbor cell’s TCI state is known or unknown. The total delay time to perform the TCI state switch can impacted by this the known/unknown statuses. Other factors can also contribute to the total delay time. The UE may also signal its capability to monitor the TCI state of the neighbor cell and its capability to switch to such a TCI state.

This disclosure provides systems, methods, and apparatus for wireless communications that support fast user equipment (UE) handover between base stations. A UE may receive, from a source base station, a configuration for reference signal transmission at a set of uplink transmit power levels. The UE may transmit multiple uplink reference signal repetitions based on the configuration. The source base station may transmit a request message to a target base station to measure the multiple uplink reference signal repetitions. The target base station may select an uplink reference signal and measure a transmit power correction. The target base station may transmit an indication to the source base station of the selection and transmit power correction. The source base station may evaluate the indications and select the target base station. The source base station may forward to the indicated contents, and the UE may switch and synchronize with the target base station.

A terminal in a wireless communication system is provided. The terminal includes a transceiver, and at least one processor configured to receive, from BS, a RRC reconfiguration message including a reconfiguration with synchronization, transmit, to the BS, a first message including a PRACH, a PUSCH, and a C-RNTI MAC CE based on the reconfiguration with synchronization, control the transceiver to receive, from the BS, a first PDCCH and a PDSCH, wherein: for the case when the BS receives the PRACH and does not receive the PUSCH, the first PDCCH is a PDCCH addressed to RA-RNTI and the PDSCH includes a fallback RAR; and for the case when the BS receives the PUSCH, the first PDCCH is a PDCCH addressed to a C-RNTI corresponding to the C-RNTI MAC CE and the PDSCH includes an absolute timing advance command MAC CE, determine that a RAR reception is successful based on the at least one of the fallback RAR or the PDSCH, when a DRX is configured for the terminal via a RRC signalling, determine that active time for the DRX includes a time while a second PDCCH indicating new transmission addressed to a C-RNTI corresponding to the C-RNTI MAC CE has not been received after determining that the RAR reception is successful, and monitor the second PDCCH during the active time.

Systems and methods for facilitating handover reduction in satellite systems are disclosed. A system may include a processor and a memory storing instructions, which when executed by the processor, may cause the processor to detect a user terminal that is selected for a handover procedure. The handover procedure may facilitate a switch from a source beam to a target beam. Based on input data, the processor may evaluate an ideal time value pertaining to a pre-defined time instance at which a scheduled handover is to be performed. The scheduled handover may correspond to at least one of a scheduled change in operating frequency within same beam or a scheduled feeder link handover due to a change in gateway communicating with the satellite. Based on the evaluation and the input data, the processor may estimate an optimized time value that pertains to an optimized time instance associated with an expected handover reduction.

This application discloses a connection establishment method, apparatus, device, and storage medium. The method includes: receiving, by user equipment UE camp on or connected to a single frequency network SFN cell group, access-related information sent by a network-side device; and establishing a connection with a target cell based on the access-related information, where the target cell is a cell/TRP layer specific cell or transmission reception point.

A transmission control method includes sending or receiving, by a first device, first data to or from a second device through a first communication connection, detecting, by the first device when sending or receiving the first data to or from the second device through the first communication connection, that an error has occurred on the first communication connection, and sending, by the first device, error information of the first communication connection to the second device through a second communication connection, where the second communication connection is different from the first communication connection, and the error information indicates that the error has occurred on the first communication connection.