A smart time-frequency exciser for spread spectrum communications

A smart adaptive time-frequency (ATF) excision algorithm is proposed to perform interference suppression in spread spectrum communications. The ATF exciser has the intelligence of deciding the domain of the excision. Additionally, adaptive subband transforms are utilized for frequency domain excision in order to track the spectral variations of the incoming signal. This adaptive transform approach brings significant performance improvements in spectral resolution. Bit error rate (EER) performance of the novel ATF exciser-based direct sequence spread spectrum (DSSS) system receiver is compared with other existing transform domain-based DSSS receivers. Time localized or frequency-localized interferer types and additive white Gaussian noise (AWGN) channels are considered in the study. In all cases, the smart ATF exciser-based DSSS receiver drastically outperforms the existing competitors. Its robust performance against the variations of the interferers is verified