Second Order Polynomial Receiver Window for Narrowband Interference Suppression in IEEE802.11a System

Orthogonal frequency division multiplexing (OFDM) has been adopted as the physical layer transmission technology in IEEE802.11a standard, where the Fourier transform is used in demodulation. Because of the effect of spectral leakage in discrete Fourier transform, narrowband interference is spreaded in spectrum domain to impact adjacent subcarriers. Receiver window function was previously proposed to suppress narrowband interference in OFDM systems. In this paper, we propose a novel Nyquist window for OFDM receiver and we also choose several other Nyquist windows for analysis and simulation in IEEE802.11a system based on the indoor wireless environment. The results of analysis and simulation show the receiver window can suppress NBI and reduce the BER, especially in the case of the novel Nyquist window adopted.