Turbo Detection in Rayleigh flat fading channel with unknown statistics

The turbo detection of turbo coded symbols over correlated Rayleigh flat fading channels generated according to Jakes’ model is considered in this paper. We propose a method to estimate the channel signal-to-noise ratio (SNR) and the maximum Doppler frequency. These statistics are required by the linear minimum mean squared error (LMMSE) channel estimator. To improve the system convergence, we redefine the channel reliability factor by taking into account the channel estimation error statistics. Simulation results for rate 1=3 turbo code and two dierent normalized fading rates show that the use of the new reliability factor greatly improves the performance. The improvement is more substantial when channel statistics are unknown.

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