Interference cancellation for multimedia satellite communication systems employing superposed transmission

摘要

This paper proposes an interference cancellation scheme for multimedia satellite communication systems, and presents results of hardware experiments on the scheme. In order to achieve higher frequency utilization efficiency, the high-speed TDM forward link signal and the low-speed spread spectrum FDMA return link signals are superposed. The conventional interference cancellation scheme utilizes a replica signal whose amplitude, phase and timing are fixed. It is virtually impossible to adjust them properly because factors such as equipment performance and propagation conditions vary irregularly. The proposed scheme is able to generate an accurate replica by utilizing a delay variation compensator and an adaptive filter.