Turbo Decoding of Hidden Markov
نویسندگان
چکیده
We describe techniques for joint source-channel coding of hidden Markov sources using a modiied turbo decoding algorithm. This avoids the need to perform any explicit source coding prior to transmission, and instead allows the decoder to utilize the a priori structure due to the hidden Markov source. In addition, we present methods that allow the decoder to estimate the parameters of the Markov model. In combination, these techniques allow the decoder to identify, estimate, and exploit the source structure. The estimation does not degrade the performance of the system, i.e. the joint estimation/decoding allows convergence at the same noise levels as a system in which the decoder has perfect a priori knowledge of the source parameters.
منابع مشابه
Simplified Methods for Combining Hidden Markov Models and Turbo Codes
AND TURBO CODES Javier Garcia-Frias and John D. Villasenor Electrical Engineering Department University of California, Los Angeles Abstract|Hidden Markov models have been widely used to statistically characterize sources and channels in communication systems. In this paper we will consider their application in the context of turbo codes. We will describe simpli ed techniques for modifying a dec...
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