Interference Cancellation of AM Narrowband Interference Signals

In this paper, we consider an overlay system where narrowband AM signals interfere with a broadband multicarrier system (M. Schnell et al., 2004). To reduce the effect of the AM narrowband interference on the multicarrier system, we propose a low complexity algorithm to estimate AM narrowband interference. We derive analytical expressions for the performance of the estimator and verify the results with simulations. The proposed estimator is able to produce accurate estimates of the frequencies, and track the time-varying amplitudes of the AM signals. The estimator can reduce the power of the AM signal to a level that is approximately 20 dB lower than the multicarrier power, independent of the AM signal power.