Architecture to support network-wide multiple-in-multiple-out wireless communication over a downlink

A method of coordinated downlink transmission from a plurality of base stations to at least one mobile unit, the method being implemented in a first base station that is one of the plurality of base stations and comprising:

• providing, to a control plane entity and from the first base station, channel state information for at least one wireless communication channel between at least one antenna associated with the first base station and at least one antenna associated with said at least one mobile unit and queue state information indicative of a status of queues for data to be transmitted over the downlink to said at least one mobile unit;
• receiving, from the control plane entity and at the first base station, transmission formats for synchronized downlink transmissions from the first base station to said at least one mobile unit, the transmission formats being determined by the control plane entity for the plurality of base stations based on the channel state information and the queue state information transmitted to the control plane entity and additional channel state information and queue state information provided to the control plane entity by at least one second base station from the plurality of base stations;
• and
• transmitting data over the downlink in coordination with the plurality of base stations using the received transmission formats so that synchronized downlink transmissions from the plurality of base stations combine coherently and constructively at said at least one mobile unit.

A method of coordinating downlink transmissions from a plurality of base stations to at least one mobile unit, the method being implemented in a control plane entity and comprising:

• receiving, at the control plane entity and from each of the plurality of base stations, channel state information for a plurality of wireless communication channels between the plurality of base stations and said at least one mobile unit;
• dynamically determining, at the control plane entity, relative time delays between legs of backhaul links between the control plane entity and antennas associated with the plurality of base stations, wherein dynamically determining the relative time delays comprises transmitting a timing signal from the control plane entity to the plurality of antennas and receiving echoes of the timing signal at the control plane entity from the plurality of antennas;
• determining, at the control plane entity and based on the channel state information, transmission formats for downlink transmissions from the plurality of base stations to said at least one mobile unit so that said downlink transmissions combine coherently and constructively at said at least one mobile unit, wherein determining the transmission formats comprises determining the transmission formats based on the relative time delays;
• and
• providing the transmission formats to the plurality of base stations.