Methods for mobility operations based on lower-layer trigger conditions are provided herein. A method performed by a wireless transmit/receive unit (WTRU) may include receiving a configuration message from a network node associated with a serving cell. The message indicates a conditional reconfiguration which, when executed by the WTRU, causes the WTRU to perform a handover to a target cell for performing handover to a target cell. The message indicates a trigger condition which, when met, causes the WTRU to execute the conditional reconfiguration. The method may include sending a measurement report including one or more measurements associated with the target cell, receiving a message from the network node, and immediately executing the conditional reconfiguration and performing the handover to the target cell.

Aspects described herein relate to wireless communications. According to some aspects, a first base station may coordinate with a second base station to select beamforming codewords. The first base station may receive an index indicating beamforming codewords used by a second base station. The first base station may select a beamforming codeword for use in transmitting signals to a wireless device based on the beamforming codeword indicated by the second base station.

A system and a method for synchronization and link acquisition in cellular wireless systems with directional antennas are disclosed. In an embodiment a method for wireless communication includes synchronizing, by a first network controller, transmission of a first synchronization signal with transmission of a second synchronization signal from another network controller.

Certain aspects of the present disclosure provide techniques for supporting mobility management in a wireless communication system employing beams. A UE may receive, from a BS serving the UE, information regarding one or more reference beams and one or more event triggers associated with the one or more reference beams. The UE may detect one of the event triggers and may take one or more actions based, at least in part, on the detected event trigger.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a relay user equipment (UE) may detect a beam failure on an access link. The relay UE may transmit, to a network entity and responsive to the beam failure, information indicating that a UE, that uses the relay UE for relaying communications with the network entity, is to use a different relay UE. Numerous other aspects are described.

An electronic device may include: a plurality of antenna modules; a communication circuit connected to the plurality of antenna modules; and at least one processor configured to: receive a first message from a first base station, which is a serving base station of the electronic device; identify, from among the plurality of antenna modules, a first antenna module for forming a first reception beam; identify, from among the plurality of antenna modules, a second antenna module for forming a second reception beam; and perform handover from the first base station to a second base station on the basis of transmitting a second message including first information for indicating the quality of at least one first signal through the first reception beam and second information for indicating the quality of at least one second signal through the second reception beam.

[Object] To make it possible to further increase a possibility of a success in a handover.

[Solution] A first apparatus of the present invention includes: a first communication processing unit configured to transmit reference signals using beamforming; and a second communication processing unit configured to receive a handover message from a source base station of a handover of a terminal apparatus. The handover message includes beam related information related to a beam. The first communication processing unit is configured to receive an access signal of the terminal apparatus based on the beam related information.

Certain aspects of the present disclosure provide various techniques for beam recovery. For example, a method for wireless communication by a network entity may include providing configuration information to a user equipment (UE) indicating a sequence of target beams and timing information to try each target beam in the sequence, and attempting to communicate with the UE using one or more of the target beams according to the timing information, in response to a beam failure.

Methods and apparatuses for controlling a cluster for a terminal device served by a radio node are described. A 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.

According to one or more aspects, a serving base station may transmit a message to a target base station based on a handover decision for a wireless device. The message may include first measurement configuration parameters for the wireless device and/or an indication of a number of channel state information (CSI) processes supported by the wireless device. The serving base station may receive a response from the target base station indicating second measurement configuration parameters for use by the wireless device after handover. The serving base station may transmit a handover command to the wireless device including the second measurement configuration parameters.