IDD-BWMA channel estimation for W-CDMA reverse link using pilot symbols over fast Rayleigh-fading multipath channels

This paper presents channel estimation of an asynchronous W-CDMA reverse link using two interpolation algorithms in frequency-selective Rayleigh fading channels. The proposed algorithms are 2-point second-order interpolation and interpolated decision-directed (IDD) block-wise moving average (BWMA) algorithm. The 2-point second-order interpolation algorithm is to modify the 3-point Gaussian interpolation algorithm. The IDD-BWMA algorithm performs two-stage processes. The first stage performs data decision to make a virtual pilot channel by using a linear interpolation channel estimation scheme. Then, the second stage performs the channel estimation of the “block-wise moving average” type by using a virtual pilot channel obtained in the first stage. By using Monte-Carlo computer simulations, we show that two kinds of the channel estimator are superior to other estimation schemes such as the WMSA(K=1) and DD-RAKE at higher Doppler frequencies