DIGITALLY IMPLEMENTED ADAPTIVE LMS SUPPRESSION FILTER FOR DIRECT SEQUENCE SPREAD SPECTRUM COMMUNICATIONS.

Least-mean-squared (LMS) adaptive filtering is a useful technique for suppressing narrowband jammers in a direct sequence spread spectrum receiver. This paper describes a digital LMS adaptive filter which implements the Widrow-Hoff LMS algorithm using a burst processing technique to reduce the multiplier count. In addition, this filter is used to suppress tone and narrowband Gaussian jammers in a 31-chip pseudonoise (PN) spread spectrum system. Experimental bit error rate (BER) results are presented which compare performance of the adaptive receiver with a nonadaptive receiver.