Feedback cancellation method based on the convex combination algorithm for T-DMB Repeaters

Abstract

This paper presents a feedback cancellation method (FCM) for T-DMB repeaters. The conventional FCM applicable to T-DMB repeaters has a good feedback cancellation performance but may distort the out-band spectrum. This distortion is a crucial obstacle for commercializing T-DMB repeaters. The FCM with prewhitening filters (PWFs) could be considered to compensate the out-band spectrum distortion. However the severe performance degradation occurs when the feedback channel varies rapidly with Doppler effects. To compensate the outband spectrum distortion and cope with the variation of feedback channel, we propose an FCM based on the convex combination algorithm (CCA). Simulation results show thatthe proposed FCM not only removes the out-band spectrum distortion of the recovered signal but also improves the feedback cancellation performance.