The embodiment of the invention provides a method, device and
system for frequency resource sharing, relates to the field of communication, and is used for improving the
frequency sharing efficiency between equipment. The method comprises the steps as follows: a second
base station receives first
base station user information sent by first
base station users; whether null space having no interference with first
station users exists in the airspace of the second base
station or not is determined according to the first base
station user information; if the fact that null space having no interference with first station users exists in the airspace of the second base station is determined, the null space is used as a
signal emission subspace of the second base station, and the second base station signals are transmitted with any transmission power less than or equal to the greatest transmission power of the second base station; if no existence of null space in the airspace of the second base station is determined, under the premise of interference and restriction on the first base station users, a
signal channel subspace and the transmission power which enable the
throughput of the second base station to be the most are chosen, and the second base station signals are transmitted with the chosen the transmission power in the chosen
signal channel subspace.