Relay UE selection
Inter-alia, a method is disclosed comprising: determining a suitability to serve as a relay device for a relayed communication between a first device and a second device via one or more relay devices to be selected among one or more relay device candidates; transmitting a message as part of a relay discovery procedure, and with the apparatus acting as one of the one or more relay device candidates; and performing at least one of a transmit power adjustment and/or a radio resource selection for transmitting the message based, at least in part, on the determined suitability.
1 . An apparatus, comprising:
at least one processor; and
at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least perform:
obtaining a configuration by receiving the configuration from a mobile communication network;
receiving a communication request message transmitted by a first device;
determining a suitability to serve as a relay device for a relayed communication between the first device and a second device via one or more relay devices to be selected among one or more relay device candidates,
wherein the first device and the second device comprise user equipment, UE, and the relayed communication comprises a relayed sidelink, SL, UE-to-UE communication,
wherein the suitability is determined based on:
whether at least one service is to be provided via the relayed communication,
whether a service, application, or group identifier carried in the communication request message is included as a configured service of the obtained configuration,
a range between the apparatus and a prior-hop device along a discovery path from the first device to the second device through the apparatus,
a Reference Signal Received Power, RSRP of a reference signal transmitted by the prior-hop device, and
a Reference Signal Received Quality, RSRQ of a reference signal transmitted by the prior-hop device;
transmitting a message as part of a relay discovery procedure, and with the apparatus acting as one of the one or more relay device candidates,
wherein the message comprises control information indicative of a relay selection factor, RSF, which is adjustable by the apparatus prior to transmitting the message,
wherein the message is transmitted responsive to receiving the communication request message; and
performing a transmit power adjustment and a radio resource selection for transmitting the message based, at least in part, on the determined suitability,
wherein the performing is based on weighted criteria, the weighted criteria comprising:
a condition of a prior hop along a discovery path from the first device to the second device through the apparatus;
a resource availability:
a resource stability;
a relaying load of the apparatus; and
one or more Quality of Service, QoS, requirements of at least one service to be provided via the relayed communication,
wherein a respective weight of each weighted criterion of the weighted criteria is selected based on the following conditions:
considering a reason for establishing the relayed communication; and
considering a hop index of the apparatus along a discovery path from the first device to the second device through the apparatus,
wherein the radio resource via which the message is transmitted indicates SL Discontinuous Reception, DRX, information associated with the apparatus.