Analog Codes on Graphs

Nandakishore Santhi; Alexander Vardy

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Analog Codes on Graphs

Nandakishore Santhi·Alexander Vardy

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Abstract

We consider the problem of transmission of a sequence of real data produced by a Nyquist sampled band-limited analog source over a band-limited analog channel, which introduces an additive white Gaussian noise. An analog coding scheme is described, which can achieve a mean-squared error distortion proportional to $(1+SNR)^{-B}$ for a bandwidth expansion factor of $B/R$, where $0 < R < 1$ is the rate of individual component binary codes used in the construction and $B \geq 1$ is an integer. Thus, over a wide range of SNR values, the proposed code performs much better than any single previously known analog coding system.

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Nandakishore Santhi, Alexander Vardy. 2006-08-22. Analog Codes on Graphs. https://arxiv.org/abs/cs/0608086

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