Performance analyses of communications receivers employing wavelet-domain minimum mean-squared error equalizers

In this paper the strategy of Minimum Mean-Squared Error (MMSE) equalization of Discrete Wavelet Transform (DWT) coefficients of received signals is applied in communications receivers. Specifically, the performance of such wavelet-based receivers under a diverse range of conditions is systematically evaluated with the use of Monte Carlo simulations. To determine the robustness of this new type of receiver processing strategy multipath fading channels, four different wavelets, and 16-symbol Quadrature Amplitude Modulation (16-QAM) are used. All faded signals are corrupted with Additive White Gaussian Noise (AWGN). For each case the system performance is quantified by Symbol Error Rates (SERs) obtained from the Monte Carlo simulations. The resulting SER curves show that the performance of DWT-based MMSE equalization is similar to the method implemented in discrete time-domain. Hence, DWT-based MMSE equalization is an effective and practicable technique that can be used in communications receivers. In particular the method can be used in agile radio receivers built upon a wavelet-domain signal processing platform.