FM jammer excision by using time-varying AR filter in spread spectrum communication systems

The time varying jammer signal degrades the performance of spreading spectrum communication systems. In this paper, time-varying autoregressive (TV-AR) modelling is used to represent nonstationary jammer signals. The modelling approach leads to an effective technique for jammer excision. In this work, jammer components parameterized by their instantaneous frequencies (IF) are effectively removed using the TV-AR filtering. The approach results in a minimum distortion to the desired DS/SS signals in communications. In order to reduce the computation complexity, orthogonal polynomials are used for the basis function of TV-AR model.