Spatio-temporal blind adaptive multiuser detection

We propose blind multiuser detection schemes with antenna arrays, which is based on signal subspace estimation, They are a multichannel extension of t he decorrelating and minimum mean-square-error detectors, and therefore the y share their immunity to near-far effects. The blind scheme may be seen as an extension of the results in of Wang and Poor. However it is seen that c ompared with the latter results when spatial diversity is considered, the p roposed spatio-temporal detectors offer, with little attendant increase in computational complexity, a better performance. A blind adaptive implementa tion based on a new orthogonal PAST (projection approximation subspace trac king) algorithm, which is shown to be efficient for subspace tracking, is p roposed. Also, we develop a blind estimation of spatial signature based on the orthogonality between noise and signal subspaces, It is seen that the b lind adaptive multiuser detection and blind spatio temporal signature estim ation can be integrated jointly.