Turbo detection for mobile MIMO underwater acoustic communications

Turbo detection for mobile transceivers is proposed for high data-rate single-carrier multiple-input, multiple-output (MIMO) underwater acoustic (UWA) communications. The proposed detection scheme employs a MIMO Doppler preprocessor and a low-complexity MIMO turbo linear equalizer (LE). The Doppler preprocessor estimates the motion-induced Doppler shift and compensates it via symbol resampling. The preprocessed signal is then detected by the MIMO turbo LE that utilizes soft-decision minimum mean square error (MMSE) linear equalization with maximum a posteriori probability (MAP) channel decoding, thus improving the detection performance iteratively while maintaining low complexity. The proposed turbo detection scheme has been tested by field trial data collected by the SPACE08 experiment near Martha´s Vineyard, Edgartown, MA, in 2008. Excellent detection results are achieved for 2-by-8 MIMO with mobile speed around 3 knots.