A Robust Transform Domain Narrowband Interference Suppression Technique in Wireless Communications

In this paper, we propose a robust narrowband interference excision technique in wireless communications based on modulated lapped biorthogonal transform (MLBT), including the Malvar´s MLBT and the MLBT constructed by Matviyenko´s optimized window. First, we study the bit error rate (BER) performance of the MLBT-based exciser in direct sequence spread spectrum (DSSS) system theoretically. Then we study the application of MLBT to narrowband interference suppression in orthogonal frequency division multiplexing spread spectrum (OFDM-SS) and multiband (MB)-OFDM-based ultra wideband (UWB) communications by simulations. Simulation results show that the Matviyenko-MLBT-based narrowband excision technique has the improved BER performance and increased robustness with respect to the interference frequency offset relative to the modulated lapped transform (MLT)-based technique in DSSS. It is also superior to the fast Fourier transform (FFT) and the MLT-based interference suppression technique in OFDM-SS and MB-OFDM-based UWB communications.