Asymptotic design and analysis of linear detectors for CDMA systems

The asymptotic performance of the linear MMSE detector for any finite observation window and any symbol impinging the observed signal is derived for asynchronous but chip synchronous CDMA systems with random spreading. Additionally, a multistage detector that does not suffer from windowing effects and performs as well as the correspondent detector in synchronous systems is proposed. In contrast to the synchronous case, considering a sufficient large delay, the proposed multistage detector can even outperform the full rank linear MMSE detector constrained to a finite fixed observation window.