Wavelet packet domain LMS based multi-user detection

An improved wavelet packet domain least mean square (IWPD-LMS) based adaptive multi-user detection algorithm is proposed. The algorithm employs the wavelet packet transform to re-whiten the input data, and chooses the best wavelet packet basis according to a novel convergence contribution function rather than the conventional Shannon entropy. The theoretic analyses show that the inadequacy of the eigenvalue spread of the tap-input correlation matrix is ameliorated, thus the convergence performance is improved greatly. The simulation result of convergence performance and bit error rate (BER) performance as a function of the signal power to noise power ratio (SNR) are presented finally to prove the validity of the proposed algorithm.