When is Noisy State Information at the Encoder as Useless as No Information or as Good as Noise-Free State?

Rui Xu; Jun Chen; Tsachy Weissman; Jian-Kang Zhang

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arXiv · 1611.00270

When is Noisy State Information at the Encoder as Useless as No Information or as Good as Noise-Free State?

Rui Xu·Jun Chen·Tsachy Weissman·Jian-Kang Zhang

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Abstract

For any binary-input channel with perfect state information at the decoder, if the mutual information between the noisy state observation at the encoder and the true channel state is below a positive threshold determined solely by the state distribution, then the capacity is the same as that with no encoder side information. A complementary phenomenon is revealed for the generalized probing capacity. Extensions beyond binary-input channels are developed.

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Rui Xu, Jun Chen, Tsachy Weissman, Jian-Kang Zhang. 2016-11-01. When is Noisy State Information at the Encoder as Useless as No Information or as Good as Noise-Free State?. https://arxiv.org/abs/1611.00270

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