Improved adaptive STBC-TD in low-to-high mobility environments

Abstract

Our recently proposed adaptive space-time block coded transmit diversity (STBC-TD) jointly used with frequency-domain equalization and decision-feedback linear prediction (DFLP) provides a good bit-error rate (BER) performance in a high-mobility environment. However, in a low-mobility environment, the achievable BER performance degrades. In this paper, we propose an improved adaptive STBC-TD, in which the use of DFLP is adaptively decided based on the minimum mean square error (MMSE) criterion of the soft-decision symbol output. Computer simulation results show that the improved adaptive STBC-TD achieves a good BER performance over wide ranges of the transmit symbol energy-to-noise power spectrum density ratio (E_s/N₀) and the normalized maximum Doppler frequency (f_DT).