Coordination group formation and scheme selection in the presence of multi-link devices

A control apparatus for controlling coordinated communication by a plurality of access points of a wireless communication system, comprising:

• an interface configured to receive a channel characteristic measured at each of a plurality of terminal devices from a plurality of access points;
• and
• circuitry configured to:
• determine, for each terminal device of the plurality of terminal devices and for one or more candidate groups of access points out of the plurality of access points for serving the terminal device, whether or not at least one backhaul link feature meets a requirement for coordinated communication, the requirement comprising at least one of:
• a requirement for multi-link operation which the circuitry is configured to test if at least one access point out of the candidate group of access points operates with multiple active links, or
• a requirement for a coordination scheme out of one or more coordination schemes applicable to the terminal device;
• select a candidate group out of the one or more candidate groups as a group of access points for serving the terminal device based on the determining;
• and
• control, via the interface, the selected group of access points to serve the terminal device in coordinated communication,
• wherein, if the circuitry determines, for a first candidate group of the one or more candidate groups, that the backhaul link feature does not meet the requirement for the coordination scheme, the circuitry is configured to increment a maximum allowed group size of the group of access points for the terminal device and form a second candidate group out of the plurality of candidate groups not larger than the incremented maximum allowed group size, and
• wherein, if the circuitry determines, for all of the plurality of terminal devices and for the first candidate group, that the at least one backhaul link feature meets the requirement for coordinated communication, the circuitry is configured to:
• determine whether a plurality of candidate groups comprising, for each of the plurality of terminal devices, the first candidate group, meets a group formation objective, and
• increment the maximum allowed group size for all of the plurality of terminal devices and form a third candidate group out of the plurality of candidate groups for each of the plurality of terminal devices if the circuitry determines that the plurality of candidate groups does not meet the group formation objective.