Multipath delay acquisition in asynchronous doubly-selective DS/CDMA fading channels

In this letter, we investigate the problem of estimating the multipath signal delays in an asynchronous direct-sequence/code-division-multiple-access (DS/CDMA) system operating over a doubly-selective fading channel. A novel blind estimation procedure is proposed which only requires knowledge of the spreading code of the user of interest, but no prior information as to the transmitted data symbols and the structure of the multiaccess interference. Numerical examples are provided to assess the performance of the proposed algorithm.