Development of cellular repeater system with multiple radio echo suppresser

We designed a cellular repeater system with a function of suppressing radio echoes that occur between antennas set in the direction of base station and mobile stations. The designed system can automatically detect and suppress radio echoes due to reflected waves from surrounding structures as well as that due to direct antenna coupling. Based on the designed system, we developed a 2-GHz band repeater applicable to the cdma2000 system, and we confirmed through field trials that the repeater can operate at a gain of more than 80 dB when antennas set in the direction of a base station and mobile stations are mounted on the same pole, when a multiple radio echo suppresser is activated.