A method for narrowband interference mitigation in OFDM by minimizing spectral leakage

Current generation narrowband power-line communication systems are OFDM based. They are especially susceptible to narrowband interference (NBI) which is generated by switching power supplies and legacy communication systems. In this paper we propose a novel method for mitigating the effect of NBI. The method exploits a well-known characteristic of NBI spectral leakage in that it is frequency dependent. The method involves intentionally introducing inter-carrier interference at the receiver in a controlled manner in order to mitigate the NBI effect with low computational complexity. A simple NBI frequency estimator is also proposed. The combined receiver solution is shown to be within 0.5 dB of the AWGN performance bound for the current G3-FCC standard in the presence of a single NBI.