Patent ID: 7430397

Claim:
A radio repeater, comprising: at least first and second relay systems, each including a reception antenna configured to receive a radio signal; a loop interference suppressor, connected to the reception antenna, configured to suppress a loop interference signal in the received radio signal from said reception antenna; an amplifier configured to amplify the loop interference-suppressed radio signal from the loop interference suppressor; and a transmission antenna having a polarization characteristic, which is orthogonal to a polarization characteristic of said reception antenna, configured to transmit an output of said amplifier, wherein the polarization characteristics of the reception antennas of said first and second relay systems are orthogonal to each other, the polarization characteristics of the transmission antennas of said first and second relay systems are orthogonal to each other, and the loop interference suppressor in each one of said first and second relay systems is configured to produce a suppression signal from the radio signal to be transmitted from the other one of said first and second relay systems and to suppress the loop interference signal in the received radio signal from the reception antenna of said one of the first and second relay systems.