Blind adaptive algorithm for demodulation of DS/CDMA signals with mismatch

摘要

The minimum mean-squared error (MMSE) linear detector is known to be a near-far resistant strategy for direct-sequence code-division multiple access systems. The MMSE linear detector can be implemented adaptively by the MOE adaptation algorithm or the Griffiths (1969) adaptation algorithm, which utilises the desired signal vector for initial adaptation instead of training sequences. The performance loss caused by the imprecise knowledge of the desired signal vector is investigated. A new blind adaptive algorithm is presented to mitigate the effect of the mismatch caused by the timing error in acquisition. Several numerical results show that the new algorithm can provide a resistance to the effect of mismatch compared to the MOE and Griffiths algorithms.