Pre-Decoder Processing Functions for a DMC with Mismatched Decoding
<|reference_start|>Pre-Decoder Processing Functions for a DMC with Mismatched Decoding: 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.<|reference_end|>
@article{solel2024pre-decoder,
    title={Pre-Decoder Processing Functions for a DMC with Mismatched Decoding},
    author={Jonathan Solel, Anelia Somekh-Baruch},
    journal={arXiv preprint arXiv:2406.17476},
    year={2024},
    archivePrefix={arXiv},
    eprint={2406.17476},
    primaryClass={cs.IT math.IT}
}