Channel State Information Reference Signal (CSI-RS) for Layer-3 (L3) Mobility

A method for communicating a channel state information reference signal (CSI-RS) in a communication network, the method comprising:

• receiving, by a user equipment (UE), an indication from a serving base station, the indication identifying a CSI-RS configuration of a neighboring base station;
• receiving, by the UE, one or more beamformed synchronization signal (SS) blocks from the neighboring base station;
• and
• monitoring, by the UE, one or more downlink channels for beamformed CSI-RSs of the neighboring base station in accordance with a subset of CSI-RS antenna ports, the subset of CSI-RS antenna ports being selected from a set of CSI-RS antenna ports based on the one or more beamformed SS blocks and the CSI-RS configuration of the neighboring base station.

A user equipment (UE) comprising:

• a processor;
• and
• a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:
• receive an indication from a serving base station, the indication identifying a CSI-RS configuration of a neighboring base station;
• receive one or more beamformed synchronization signal (SS) blocks from the neighboring base station;
• and
• monitor one or more downlink channels for beamformed CSI-RSs of the neighboring base station in accordance with a subset of CSI-RS antenna ports, the subset of CSI-RS antenna ports being selected from a set of CSI-RS antenna ports based on the one or more beamformed SS blocks and the CSI-RS configuration of the neighboring base station.

A method for notifying users of channel state information reference signal (CSI-RS) configurations of neighboring cells in a communication network, the method comprising:

• receiving, by a target base station, an indication from a serving base station that a served UE has received a synchronization signal (SS) block from the target base station;
• configuring CSI-RS antenna ports of the target base station based on a coarse beam direction used to transmit the detected SS block;
• and
• transmitting CSI-RS symbols over the CSI-RS antenna ports, the CSI-RS antenna ports being quasi-co-located (QCL'd) with an antenna port used to transmit the SS block.