Blind joint equalization of multiple synchronous mobile users using oversampling and/or multiple antennas

• Published in: Proceedings of 1994 28th Asilomar Conference on Signals, Systems and Computers Vol. 2; pp. 1154 - 1158 vol.2
• Main Author: Slock, D.T.M.
• Format: Conference Proceeding
• Language: English
• Published: IEEE Comput. Soc. Press 1994
• Subjects: Additive noise; Blind equalizers; Chirp modulation; Digital modulation; Equations; Finite impulse response filter; Mobile antennas; Mobile communication; Noise cancellation; Receiving antennas
• ISBN: 0818664053; 9780818664052
• ISSN: 1058-6393
• DOI: 10.1109/ACSSC.1994.471640

We consider multiple (p) users that operate on the same carrier frequency and use the same linear digital modulation format. We consider m>p antennas receiving mixtures of these signals through multipath propagation (equivalently, oversampling of the received signals of a smaller number of antenna signals could be used). We consider conditions on the matrix channel response for the existence of a zero-forcing equalizer (ZFE) (which cancels intersymbol and inter-user interference). In the noise free case, we show how a ZFE can be obtained from linear prediction and the channel matrix itself can also be determined as a byproduct. The problem is one of signal and noise subspaces and we show a convenient way of solving the deterministic maximum likelihood problem using a minimal linear parameterization of the noise subspace. This parameterization is found as a byproduct in the linear prediction problem.< >