Cyclostationarity-based filtering for narrowband interference suppression in direct-sequence spread-spectrum systems

This paper addresses the problem of narrowband interference suppression in direct-sequence spread-spectrum (DS/SS) techniques, which have been adopted in the last decade to implement code divsion multiple access (CDMA) system s for wireless mobile communications. The recently developed theory of cycl ic Wiener filtering, based on the cyclostationarity assumption for the sign als involved in the reception problem, is applied to design single-channel adaptive frequency-shift filters which exploit both temporal and spectral c orrelation properties, i.e., the correlation between time- and frequency-sh ifted versions of the received signal. The numerical results show that rece iving structures based on the proposed cyclostationarity-based interference suppression schemes largely outperform receivers that utilize conventional linear time-invariant suppressors, when they operate in highly contaminate d interference environments.