Employing LSF at Transmitter Eases MMSE Adaptation at Receiver in Asynchronous CDMA Systems

In this paper, the authors have presented an efficient structure employing two kinds of optimal FIR filters, respectively, at the transmitter and the receiver for asynchronous CDMA systems. They have demonstrated that the use of the LSF-code with an adaptive linear receiver yields significant reduction in adaptation-time. The study of autocorrelation properties has shown that the MMSE receiver with the LSF-code has similar correlation to the LSF-code itself in a wide range of scenarios, the average correlation of the MMSE receiver with a random code in asynchronous systems would roughly be identical to that of the LSF, and there is a notable difference between synchronous and asynchronous cases for the MMSE receiver.