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arXiv · 2406.17476

Pre-Decoder Processing Functions for a DMC with Mismatched Decoding

Abstract

This paper analyzes the effect of adding a pre-decoder processing function to a receiver that contains a fixed mismatched decoder at the output of a discrete memoryless channel. We study properties of the symbolwise pre-processing function and show that it is a simple yet very powerful tool which enables to obtain reliable transmission at a positive rate for almost every metric. We present lower and upper bounds on the capacity of a channel with mismatched decoding and symbolwise(scalar-to-scalar) pre-processing, and show that the optimal pre-processing function for random coding is deterministic. We also characterize achievable error exponents. Finally, we prove that a separation principle holds for vectorwise(vector-to-vector) pre-processing functions and further, that deterministic functions maximize the reliably transmitted rate in this case.

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BibTeXRIS

Jonathan Solel, Anelia Somekh-Baruch. 2024-06-25. Pre-Decoder Processing Functions for a DMC with Mismatched Decoding. https://arxiv.org/abs/2406.17476

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