A wireless device receives one or more radio resource control (RRC) messages indicating a handover from a first cell to a second cell and a synchronization signal block (SSB), of the second cell, for receiving a downlink control information (DCI) from the second cell. The wireless device receives, from the second cell and based on a demodulation reference signal (DMRS) antenna port being quasi co-located with the SSB, the DCI scheduling an uplink transmission, wherein the uplink transmission is an initial uplink transmission, to the second cell, after receiving the one or more RRC messages indicating the handover. The wireless device transmits, to the second cell and based on the SSB indicated by the one or more RRC messages, the uplink transmission.

The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4th-Generation (4G) communication system such as Long Term Evolution (LTE). The present invention provides a method for supporting handover, comprising the steps of: informing, by a source base station, a core network whether a direct data forwarding path is available; deciding, by the core network, whether to use direct data forwarding or indirect data forwarding; informing, by the core network, a target base station of information about the direct data forwarding or indirect data forwarding; allocating, by the target base station, data forwarding tunnel information, the target base station allocating the data forwarding tunnel information according to the received information about the direct data forwarding or indirect data forwarding; transmitting, by the target base station, the allocated data forwarding tunnel information to the core network; and informing, by the core network, the source base station of the data forwarding tunnel information. With the present invention, different data forwarding methods are supported to prevent data loss and ensure service continuity.

This disclosure relates to performing beam failure recovery during an inter-cell connection involving a UE in communication with one or more base stations in a cellular communication system. In various embodiments, a user equipment determines one or more beam failures by monitoring one or more reference signals transmitted by one or more base stations, where the UE is connected to the one or more base stations. The UE further performs candidate beam detection by monitoring at least one candidate reference signal that is transmitted by one or more candidate base stations, where at least one candidate base station (a first candidate base station) is different from the one or more base stations to which the UE was previously communicating. The UE selects the first candidate base station based on the candidate beam detection, and transmits a beam failure recovery request (BFRQ) message to the first candidate base station based on the selection.

Techniques for beam-based relay node switch. An example method of wireless communication by a first wireless node generally includes relaying wireless communications between a user equipment (UE) (120, 120a-y) and a network entity; transmitting, to one or more second wireless nodes, relay request signals via a plurality of beams (402a-d, 602a-d, 604a-b, 706a-b) at relay request signal occasions (1, 2, 3), wherein each of the relay request signals indicates a request to switch relay services of the UE (120, 120a-y) from the first wireless node to the one or more second wireless nodes; and switching the relay services of the UE (120, 120a-y) to at least one of the one or more second wireless nodes.

Embodiments of the present disclosure relate to lower layer triggered mobility. In an aspect, a terminal device receives a radio resource control signaling including a transmission configuration indicator from a first network device. The transmission configuration indicator state is configured for beam-only-switching. The terminal device performs beam-only switching based on the transmission configuration indicator state and a first switching command, then configuration switching based on the first switching command or a second switching command. As such, a solution for enhanced lower layer triggered mobility is provided, thereby reducing the interruption time.

The present disclosure relates to a method used in a cluster manager controlling a cluster for a terminal device served by a radio node, and to the associated cluster manager. The cluster manager is under control of a control node and the cluster includes the radio node. The method includes: receiving Layer 1 (L1)/Layer 2 (L2) measurements of the terminal device on the radio node and one or more neighboring radio nodes of the radio node; determining a target radio node, to which the terminal device is to be handed over, based on the L1/L2 measurements; determining whether the target radio node is within the cluster; and if it is determined that the target radio node is within the cluster, determining whether the terminal device is to perform handover from a beam of the radio node to a beam of the target radio node.

A method for handover in a wireless communication system includes: when a received signal strength difference between a serving beam from a serving base station used for communication by a terminal and a target beam of a neighboring base station is equal to or greater than a first threshold value, and a received signal strength difference between an active beam and the target beam is equal to or greater than a second threshold value, determining a handover to the target beam; and transmitting a message to initiate the handover.

A system that incorporates the subject disclosure may include, for example, a circuit for determining a magnitude difference between a first signal supplied to an antenna and a second signal radiated by the antenna, determining a phase difference between the first signal supplied to the antenna and the second signal radiated by the antenna, measuring a change in reactance of an antenna, detecting an offset in an operating frequency of the antenna based on one of the magnitude difference, the phase difference, the change in reactance, or any combination thereof, and adjusting a resonant frequency of the antenna to mitigate the offset in the operating frequency of the antenna. Other embodiments are disclosed.

The present invention is designed to enable quick beam recovery. A user terminal according to the present invention has a receiving section that receives a downlink (DL) signal, and a control section that controls a beam that is used to transmit and/or receive the DL signal, and the control section controls transmission of an uplink (UL) signal that requests switching of the beam, based on the received power and/or the received quality of a plurality of mobility measurement signals that are respectively associated with a plurality of beams.

Embodiments of the present application relate to a method and apparatus for implementing high-frequency communication. The method includes: receiving, by a high-frequency base station, a scan request message sent by a base station originally connected to user equipment (UE); sending, by the high-frequency base station, a scan acknowledgment message to the base station originally connected to the UE, receiving, by the high-frequency base station, information about the UE sent by the base station originally connected to the UE; and scanning the UE, by the high-frequency base station, according to the information about the UE, so as to re-establish a high-frequency connection between the UE and the high-frequency base station.