Multi-tone interference suppression in DSSS system based on the optimal frequency shift of undecimated wavelet packets

A new algorithm for narrowband interference suppression in Direct Sequence Spread Spectrum (DSSS) system is presented. The algorithm combines the optimum frequency shift and the Undecimated Wavelet Packet Transform (UWPT) to locate the interference energy in as little sub-band as possible. In addition, the adaptive algorithm is used to reduce the harm to the signal caused by eliminating the disturbed sub-band. Simulation results show that the proposed algorithm has a better performance than the traditional Undecimated Wavelet Packet Transform with frequency shift (SUWPT) algorithm in the suppression of the Multi-Tone Interference (MTI).