A new adaptive co-site broadband interference cancellation method with auxiliary channel

Abstract

With the boom of the communication systems on some independent platforms (such as satellites, space stations, airplanes, vessels), co-site interference is becoming prominent. The adaptive interference cancellation method has been adopted to solve the co-site interference problem. But the broadband interference cancellation performance of traditional Adaptive Co-site Interference Cancellation System (ACICS) with large delay mismatching and antenna sway is relatively poor. This study put forward an Adaptive Co-site Broadband Interference Cancellation System With Two Auxiliary Channels (ACBICS-2A). The system model was established, and the steady state weights and Interference Cancellation Ratio (ICR) were deduced by solving a time-varying differential equation. The relationship of ICR, system gain, modulation factor, interference signal bandwidth and delay mismatching degree was acquired through an in-depth analysis. Compared with traditional adaptive interference cancellation system, the proposed ACBICS-2A can improve broadband interference cancellation ability remarkably with large delay mismatching and antenna sway for the effect of auxiliary channel. The maximum improved ICR is more than 25dB. Finally, the theoretical and simulation results were verified by experiments.