Modulation Diversity for Wireless Communications: Impact of Channel Estimation Errors and Doppler Effects on System Performance
The performance of wireless communications systems can be significantly improved using the modulation diversity technique which is, basically, based on the combination of a suitable choice of the reference angle of an MPSK constellation with independent interleaving of the symbol components. This technique presents good performance assuming the absence of estimation errors for channels characterized by flat fading. In this article, the performance of this recent technique is analyzed taking into account the effects of channel estimation errors. It is shown, by simulation, that the efficiency of this technique is maintained even under this assumption. Additionally, the impact of the Doppler effect on the system performance is treated and a trade-off between the interleaving depth and the error probability is achieved.
KeywordsFading Channel Channel Estimation Modulation Diversity Network Security Reference Constellation
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