Narrowband Interference Rejection in PN Spread Spectrum Communication Systems using Decision Feedback Filters

In this paper. the performance of direct sequence (DS) spread spectrum systems using decision feedback interference suppression filters is analyzed. Analytical expressions for the filter output powers are obtainied, and their parameter dependence is quantified. In addition, under the assumption of perfect decision feedback. analytical expressions for the bit-error rates are developed and compared to simulation results. Finally, a comparison of two different decision feedback filter realizations shows the advantage of filtering the interference and noise only, excluding the desired signal.