Turbo Equalization for Channels with High Memory Using a List-Sequential (LISS) Equalizer
نویسندگان
چکیده
For multipath channels with a high number of taps and signal constellation points the APP (BCJR) soft-in/soft-out detector in a turboscheme has a prohibitively high number of states. We replace it by a novel list-sequential stack (LISS) algorithm using augmented paths and an auxiliary stack for a length dependent bias term. For BERs lower than 10 the turbo system with a LISS equalizer has almost the same performance as the turbo system with an APP equalizer, yet with much smaller complexity. Furthermore, our method still works with 10 or 20 taps and has a controllable complexity determined by the used stack sizes.
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