Adaptive channel estimation in DS-CDMA systems

Abstract

The accuracy of channel estimation (CE) significantly affects the performance of the coherent rake receiver in DS-CDMA systems. It is desirable to employ a CE scheme that can provide good estimation performance and fast tracking the channel fading with reduced complexity. Such a CE scheme needs to employ a so-called channel estimation filter (CEF) that can effectively reduce the noise effect according to the channel condition. In this paper, we consider the use of adaptive channel estimators that employ a moving average (MA) FIR filter as the CEF. Numerical results show that the use of adaptive MA FIR CEF for pilot based and hybrid CE schemes can provide a performance similar to the use of Wiener CEF, while significantly reducing the implementation complexity.