An improved transform domain adaptive narrowband interference suppression technique

To suppress the strong narrowband interference (NBI) in the direct sequence spread spectrum (DSSS), a simplified method of the NBI suppression based on wavelet package transform (WPT) is presented in this paper. Based on the power spectrum density (PSD) of the spread spectrum signal and the criterion of energy compaction measure (ECM), this method can track the change of the input signal spectrum and locate the interference in the spread spectrum signal efficiently and quickly, and then change the tap weight adaptively to suppress the strong or weak NBI separately. The simulation results show that the adaptive interference suppression method can eliminate the fast time change strong NBI and decrease the useful information loss during the processing. So the anti-interference performance of the system will be improved.