Blind multi-user linear detection of CDMA signals in frequency selective channels
David Gesbert, Arogyaswami J. Paulraj · 2002
This paper addresses the problem of multi-user detection in the context of cellular CDMA and frequency selective channels. Structures and algorithms are proposed for the receiver design, that combat both strong multiple access interference (MAI) and inter-chip interference (ICI) in possibly asynchronous networks. Two novel receiver structures are proposed. The first one allows for the estimation of the channel characteristics for one or multiple users before signal detection. The second approach is simpler and directly acquires the coefficients of several multi-user detectors with multiple delays. These methods are blind in the sense that no pilot sequences are used to estimate the coefficients of the receiver. Only the knowledge of the spreading code for the user(s) of interest is exploited here. The proposed technique is shown to outperform existing comparable receiver estimation procedures.