Abstract: In a mobile radio communications system comprising a control station and base stations, each base station is capable of sensing power levels of signals received on idle channels. In response to a polling signal periodically sent from the control station, each base station returns a signal indicating the detected power levels, the identifications of the idle channels, the identification of a busy channel or no-busy channel indication, and the identification of each of the base stations. The control station derives an interference table from the contents of the signals received from all base stations. The table defines interference coefficients between all pairs of base stations in matrix form according to the identifications of the idle and busy channels and the identifications of the base stations. From the interference coefficients a plurality of interference estimations are derived for all possible combinations of channels and base stations.

Abstract: A radio communication system comprises a plurality of subsystems each including a base station and a mobile station. A connection is to be allowed between the base and mobile stations in a subsystem by a first decision, when they have a first distance shorter than a predetermined distance therebetween. Then, the connection is finally allowed by a second decision, when the subsystem has a second distance longer than another predetermined distance therebetween from another subsystem. The first and second distances are detected in the base station by receipt levels of signals. The first distance may be changed dependent on the existence of an interference from outside subsystems.