A New Achievable Rate-Distortion Region for Distributed Source Coding

作     者：Shirani, Farhad Pradhan, S. Sandeep 

作者机构：North Dakota State Univ Elect & Comp Engn Dept Fargo ND 58103 USA Univ Michigan Elect Engn & Comp Sci Dept Ann Arbor MI 48109 USA 

出 版 物：《IEEE TRANSACTIONS ON INFORMATION THEORY》 (IEEE信息论汇刊)

年 卷 期：2021年第67卷第7期

页      面：4485-4503页

核心收录：

学科分类：0808[工学-电气工程] 08[工学] 0701[理学-数学] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：NSF [CCF 1422284  CCF 1717299] 

主　　题：Encoding Correlation Rate-distortion Decoding Markov processes Source coding Quantization (signal) Distributed source coding data compression common information finite block-length coding 

摘      要：In this work, lossy distributed compression of a pair of correlated sources is considered. Conventionally, Shannon s random coding arguments - using randomly generated unstructured codebooks whose blocklength is taken to be asymptotically large - are used to derive achievability results. However, in some multi-terminal communications scenarios, using random codes with constant finite blocklength in certain coding architectures leads to improved achievable regions compared to the conventional approach. In other words, in some network communication scenarios, there is a finite optimal value in the blocklength of the randomly generated code used for distributed processing of information sources. Motivated by this, a coding scheme is proposed which consists of two codebook layers: i) the primary codebook which has constant finite blocklength, and ii) the secondary codebook whose blocklength is taken to be asymptotically large. The achievable performance is analyzed in two steps. In the first step, a characterization of an inner bound to the achievable region is derived in terms information measures which are functions of multi-letter probability distributions. In the next step, a computable single-letter inner-bound to the achievable region is extracted. It is shown through an example that the resulting rate-distortion region is strictly larger than the Berger-Tung achievable region.