Combined Image Subband Coding and Multilevel Modulation for Communication over Power- and Bandwidth-limited Channels
نویسندگان
چکیده
This paper presents a bandwidth-eecient, power-limited still image transmission system based on subband coding and 64-QAM. A new optimization procedure, based on the simulated annealing algorithm, is used to optimize the map-pings between quantized subband samples and the modulation signal constellation. The optimization criterion is the mean square error between the transmitted and the reconstructed quantized subband samples. Assuming an additive white Gaussian noise (AWGN) channel it is shown that the proposed image transmission system gives a signiicant improvement in image quality as compared to a system with random mappings.
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