Active coordination set for mobility management

A user equipment (UE) comprising:

• one or more radio frequency (RF) transceivers;
• a processor and memory system to implement an active coordination set (ACS) manager application configured to:
• evaluate a measurement of a link quality parameter for one or more base stations;
• determine to include at least a first base station of the one or more base stations in an ACS;
• send, using the one or more RF transceivers, a message to an ACS Server, the message including an indication to add the at least the first base station to the ACS, the message causing the ACS Server to:
• store the ACS for the user equipment, the stored ACS including the indication of the at least the first base station;
• and
• send a copy of the stored ACS to a master base station;
• store the ACS including the added at least the first base station;
• communicate, using the one or more RF transceivers, via one or more of the base stations included in the ACS;
• determine that one or more of the base stations in the ACS has fallen below a threshold for the link quality parameter;
• transmit an uplink ACS sounding signal that is effective to cause candidate base stations to receive and decode the uplink ACS sounding signal;
• receive decoding results for the uplink ACS sounding signal from the candidate base stations;
• determine, using the decoding results, which of the candidate base stations to include in the ACS;
• send a message to the ACS Server including an indication of which candidate base stations to include in the ACS;
• and
• jointly communicate with one or more of the base stations included in the ACS.

An Active Coordination Set (ACS) Server device comprising:

• a network interface;
• one or more processors;
• and
• memory comprising instructions executable by the one or more processors to configure the ACS Server device to:
• receive, using the network interface and via a master base station, an ACS-Modify message from a user equipment (UE);
• retrieve, from the memory, a stored copy of an ACS associated with the UE;
• modify the retrieved copy of the ACS based on the received ACS-Modify message;
• store the modified copy of the ACS in the memory;
• if there is no stored copy of the ACS associated with the UE:
• create an ACS for the UE;
• modify the created ACS based on the received ACS-Modify message;
• and
• store the modified ACS in the memory;
• and
• send, using the network interface, a copy of the modified ACS to the master base station that is effective to cause the master base station to allocate air interface resources for communication between the UE and base stations in the ACS and schedule joint communications for the UE and the base stations in the ACS.

An Active Coordination Set (ACS) Server device comprising:

• a network interface;
• one or more processors;
• and
• memory comprising instructions executable by the one or more processors to configure the ACS Server device to:
• receive, using the network interface and via a master base station, an ACS-Modify message from a user equipment (UE);
• receive, using the network interface, a query for an ACS associated with the UE;
• retrieve, from the memory, a stored copy of the ACS associated with the UE;
• modify the retrieved copy of the ACS based on the received ACS-Modify message;
• store the modified copy of the ACS in the memory;
• send the stored copy of the ACS to the UE, via the master base station;
• and
• send, using the network interface, the stored copy of the ACS to the master base station that is effective to cause the master base station to allocate air interface resources for communication between the UE and base stations in the ACS and schedule joint communications for the UE and base stations in the ACS.