Quantizer Design for Turbo-code Channels
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چکیده
1 A preliminary version of this work has been presented in 1,2]. A more detailed version of this work is reported in 3]. Abstract A new method of combined source-channel coding using Turbo-code is presented. The corresponding system transmits a discrete time, continuous amplitude signal over an Additive White Gaussian Noise (AWGN) channel where a Turbo-code is used for error correction purposes. The proposed scheme takes advantage of the available reliability information (generated by the Turbo-code decoder) to improve the quality of the reconstructed signal. The design rules for a quantizer and reconstructor to minimize the overall mean square distortion are derived. Numerical results are presented showing up to 1 dB improvement in the end-to-end distortion with respect to a traditional channel optimized quantizer. This improvement is obtained at the price of a small increase in the system complexity.
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تاریخ انتشار 1999