Iterative PIC Detection and Channel Estimation for Satellite DS-CDMA Communications

This paper presents a Turbo Multiuser De- tector for Turbo-Coded DS-CDMA systems, based on the utilization of a PIC and a bank of turbo decoders, in which the PIC performs interference cancellation after each con- stituent decoder of the turbo decoding scheme. Moreover, the soft output of turbo decoders are used iteratively to improve the updating step of the channel parameter es- timation which is formally equivalent to one step of the expection-maximization algorithm. By means of computer simulations, we will show that the proposed receiver achieves performance comparable with systems which suppose perfect channel parameters knowl- edge for medium to high system loads, in AWGN channel. These results are obtained also in satellite channel, for dif- ferent values of the elevation angle.