Performances of the H-ARQ Adaptive-QAM Transmissions over Multipath Mobile Channels
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چکیده
This paper presents the evaluation of the average spectral efficiencies provided by the adaptive employment of a set of LDPC-coded QAM modulations in an OFDMA downlink scheme over mobile radio channels, assuming a joint channelaccess method modeling. It discusses the selection of the set of coded modulations, the setting of the SINR domains where they are optimal and derives the average spectral efficiency provided by this approach in non-ARQ or H-ARQ environments. Index Terms ― LDPC-coded QAM constellations, average spectral efficiency, chunk-error rates, SINR thresholds.
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تاریخ انتشار 2007