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Efficient channel quality feedback schemes for adaptive modulation and coding of packet data

Adaptive modulation and coding (AMC) is a powerful technique to improve throughput especially of wireless packet-oriented channels. In general such link adaptation schemes rely on feedback from the receiver, which allows selecting the appropriate modulation and coding. In this paper we evaluate the performance of different channel quality feedback schemes and propose a general performance metric, that considers data throughput, energy efficiency, channel resource consumption, as well as control overhead. At the example of the high speed downlink packet access (HSDPA) channel for UMTS FDD, we show that channel quality feedback schemes that consider the burstiness of packet data are able to provide notably higher efficiency than the cyclic feedback currently standardized.