Satellite Spread Spectrum Communication System Interference Suppression Technology Research

The spread spectrum communication technique, one of the most significant and primary technique of current and further wireless communication, is applied in wide and various fields. However, generally in the practical spread spectrum system, the influence of signal interference caused by numerous and various reasons is serious and critical. The main interference sources in spread spectrum communication are inter-symbol interference, multi-access interference and narrow-band interference which influenced most. Since the frequency of Compass (BeiDou) signal is close to the general frequency-band, the diverse interference seriously affects the signal receiving and timing applications.Recently, the interference of Compass (BeiDou) is classified as inband interference of digital intermediate frequency, which is one of the narrow-band interference.The main objective of this paper is resolving the interference of the Compass (BeiDou) signal. Aiming at narrow-band interference, the interference suppression algorithm based on frequency domain is proposed. The earlier studies accomplished the simulation on Matlab, which is under a spread spectrum system with narrow-band interference, to reconstruct the signal by the phase spectrum of the receiving signal after FFT processing and processed amplitude spectrum to reduce the power of the interference signal and achieve the interference suppression.In this paper, the interference suppression algorithm is a mature algorithm. Furthermore the several adjustments of this algorithm based on the analysis of the amplitude and frequency features of practical signal and the Matlab simulation are proposed which is extremely effective in the practical applications of this algorithm.