ONE FREQUENCY REPEATER FOR A DIGITAL MICROWAVE RADIO SYSTEM WITH CANCELLATION OF TRANSMITTER-TO-RECEIVER INTERFERENCE

摘要

Abstract of the DisclosureA digital microwave radio repeater using thesame carrier frequency for the transmitting and thereceiving carriers for improving the frequencyutilization efficiency. The transmitter-to-receiverinterference signal is cancelled by producing anestimated-interference signal of the interference signalfrom the digital baseband signal by the use of atransversal filter and by subtracting theestimated-interference signal from the received signal.The estimated-interference signal is also produced byfrequency shifting a digital modulated signal in thetransmitter. The transmitting carrier frequency islocked to the receiving carrier frequency by the use ofa phase-locking technique, so that the interferencesignal is reduced.