This paper proposes an optimal maximum a posteriori probability decoder for variable-length encoded sources over binary symmetric channels that uses a novel state-space to deal with the problem of variable-length source codes in the decoder. This sequential, finite-delay, joint source-channel decoder delivers substantial improvements over the conventional decoder and also over a system that use...

|We propose the new Group Metric (GM) decoder for convolutionally coded synchronous multiple-access channels. The GM decoder makes decoding decisions for one user, but incorporates multiuser information in its metrics. This decoder will have a reduced complexity which is exponential in the sum of encoder memory and the number of users. The soft-decision maximum-likelihood (ML) joint decoder can...

Consider the following information theoretic setup wherein independent codebooks of N correlated random variables are generated according to their respective marginals. The problem of determining the conditions on the rates of codebooks to ensure the existence of at least one codeword tuple which is jointly typical with respect to a given joint density (called the multivariate covering lemma) h...

We present a simple, effective iterative structure for joint source-channel decoding using global iterations between a source and channel decoder. The source decoder uses the Sequence Based Approximate Minimum Mean Square Error (SAMMSE) algorithm. The iterative structure is tested using both LDPC and turbo channel codes and simulations show significant performance gains over non-iterative syste...

Digital communications systems commonly use compression (source coding) and error control (channel coding) to allow efficient and robust transmission of data over noisy channels. When compression is imperfect, some residual redundancy remains in the transmitted data and can be exploited at the decoder to improve the decoder’s probability-of-error performance. A new approach to joint source-chan...

A popular view in contemporary Boltzmannian statistical mechanics is to interpret the measures as typicality measures. In measuretheoretic dynamical systems theory measures can similarly be interpreted as typicality measures. However, a justification why these measures are a good choice of typicality measures is missing, and the paper attempts to fill this gap. The paper first argues that Pitow...

An approach to joint equalization and decoding for vector quantization over a Gaussian channel with intersymbol interference is presented. The decoder is based on a Hadamard transform representation of the vector quantizer. This gives the decoder a structure that allows the decoding to be based on estimates of the transmitted bits in an efficient manner. The decoder is soft in the sense that so...

In regards to turbo codes, to the author's knowledge, previous literature has treated decoder assisted frame synchronization and channel estimation as separate processes. Here a joint decoder assisted process of channel estimation and frame synchronization is proposed. In brief, the method entails using a sync word (SW) embedded mid-packet for both channel estimation and frame synchronization. ...

Because of their excellent error-correcting performance, low-density parity-check (LDPC) codes have recently attracted a lot of attention. In this paper, we are interested in the practical LDPC code decoder hardware implementations. The direct fully parallel decoder implementation usually incurs too high hardware complexity for many real applications, thus partly parallel decoder design approac...

In this work, we study a distributed source coding problem with multiple encoders, a central decoder and a joint distortion criterion. The encoders observe correlated sources which they quantize and communicate to a central decoder through a rate constrained, noiseless channel. The objective is to minimize the distortion as measured by a joint distortion criterion that depends on the sources an...