Non-Linear Effects in Interference Contaminated Adaptive Equalization

The presence of non-linear effects in adaptive filtering was observed previously in a wide sense stationary equalization scenario with narrowband interference. The influence of a variety of parameters on the magnitude of such non-linear effects was also investigated. While the adaptive filter appears to exhibit behavior that one would expect in a wide sense stationary scenario, we show here that the adaptive filter is actually tracking a time-varying target solution. It is the latter property that is responsible for the performance improvement of the adaptive filter over the performance of the corresponding Wiener filter.