Optimization of Delay Diversity for Fading ISI Channels
نویسندگان
چکیده
In this paper, we propose an optimized delay diversity (ODD) scheme for fading intersymbol interference (ISI) channels. We derive a cost function for optimization of the ODD transmit filters and we provide a steepest descent algorithm for iterative calculation of the filter coefficients. In addition, an upper bound on the cost function is derived and employed to prove the asymptotic optimality of the generalized DD (GDD) scheme in [1] for very high signal–to–noise (SNR) ratios and transmit filters of maximum length. However, for SNRs of practical interest and reasonable filter lengths the novel ODD scheme significantly outperforms GDD for both optimum and suboptimum equalization.
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