Rejection of narrow-band interference in PN spread spectrum system using adaptive QC-LMSE filter

A method for rejection of narrowband interference in pseudonoise spread-spectrum systems is proposed. The method is based on the quadratically constrained least-mean-square-error (QC-LMSE) filtering. It is shown that perfect rejection of the single-tone interference can be achieved through appropriate choice of the constraint parameters. This method does not require any a priori knowledge about the frequency and the amplitude of the interference, and hence the filter can be made adaptive. An adaptive algorithm is developed and its learning characteristics are discussed with simulations on computer.<
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