Decision Directed Coherent Detection in Multicarrier Systems on Rayleigh Fading Channels
نویسندگان
چکیده
Novel coherent detectors for DQPSK and-DQPSK on Rayleigh fading channels are presented. The detectors are based on decision feedback and minimum mean square error (MMSE) channel estimation. The proposed detectors may be used in both single carrier and multicarrier systems. Analytical results in form of expressions for channel estimation error variance and bit error probability, both with and without diversity, are derived. The MMSE based detector has a significantly lower irreducible bit error probability floor compared to a conventional differential detector. For most practical applications the error floor of the MMSE based detector is negligible. Simulated results are presented to verify the analysis and to justify the approximations made.
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