Bit error rate analysis of digital communications signal demodulation using wavelet denoising

Communications receiver performance obtained in conjunction with de-noising of digitally modulated communications signals using wavelet signal processing is described in this paper. The study includes both simulation results and the analytical characterization of the bit error rate (BER) performance obtained for BPSK and QPSK modulation schemes. The digital communications system consists of an MPSK modulator, an additive White Gaussian noise channel, and a receiver that employs a wavelet de-noising operation followed by a matched filter detector. Overall system performance for each modulation type considered is described by means of BER curves over a range of E_b/N₀ values. It has been found that the significant improvement in BER compared to systems wherein the matched filter detector is not preceded by a wavelet de-noising operation is due to the effective increase in pre-detection signal-to-noise ratio (SNR). Statistical analysis of the de-noised modulated signals is presented. The corresponding analytical evaluation of BER for receivers using wavelet de-noising is derived.