Patent attributes
To reduce intercell interference, a method of coherently coordinated downlink transmission in a wireless network involves coordinating transmissions from a plurality of base stations to a plurality of wireless units, for coherent, reinforced reception of the transmitted signals at the wireless units. Thus, transmissions from the base stations are coordinated such that signals received at each wireless unit's particular location constructively add, but cancel out at other locations. The signals are generated based on a zero-forcing operation, e.g., by applying zero-forcing complex antenna weight vectors to data symbols designated for transmission to the wireless units. For fairness, the signals are transmitted at no less than a guaranteed common rate. A convex optimization problem (which incorporates a per-base station power constraint or a per-transmission antenna power constraint) is solved to maximize the guaranteed common rate. Dirty paper coding may also be employed.
