Patent ID: 6539226
Filing Date: 2003-03-25
Classification: H04W

Abstract:
A base station transmission power control system in a code division multi access cellular mobile radio communication system comprising a plurality of base stations respectively announcing unique pilot signals and a mobile station which is capable of simultaneously establishing connection with a soft hand over base station group consisted of some base stations out of said base stations in the system, whereinsaid mobile station detecting a communication reception quality and a primary base station among sad base stations, reception level of pilot signal of which becomes maximum among pilot signals received from respective base stations in said soft hand over base station group, notifying a base station number of said primary base station as a transmission power control signal for respective of said base stations in said soft hand over base station group when said communication reception quality is lower than a desired quality, and notifying a number other than the base station number of the base stations in said soft hand over bases group when said communication reception quality is in excess of said desired quality; and each base station in said soft hand over base station group receiving said transmission power control signal and being restricted a transmission power when a content of said transmission power control signal identifies number other than own base station number; wherein each base station in said soft hand over base station group manages two transmission power values including a first transmission power value and a second transmission power value, deceases said first transmission power value when the content of said transmission power control signal identifies number other than said base station number in said soft hand over base station group, increases said first transmission power value when the content of said transmission power control signal identifies any one of said base station number in said soft hand over base station group, selectively sets one of said first transmission power value and a minimum transmission power value as said second transmission power value, sets said first transmission power value as said second transmission power value when the content of said transmission power control signal identifies own base station number, sets said minimum transmission power value as said second transmission power value when the content of said transmission power control signal identifies said base station number in said soft hand over base station group other than own base station number, sets said first transmission power value as said second transmission power value when the content of said transmission power control signal identifies other than base station number in said soft hand over base station group and when said first transmission power value is set as said second transmission power value in the preceding time, sets said minimum power value as said second transmission power value when the content of said transmission power control signal identifies base station number other than the base station number in said soft hand over base station group and said minimum transmission power value is set as said second transmission power value in the preceding time, and takes said second transmission power value as an output value of a transmission amplifier device.