Codeword or noise? Exact random coding exponents for slotted asynchronism

Neri Merhav

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arXiv · 1308.4572

Codeword or noise? Exact random coding exponents for slotted asynchronism

Neri Merhav

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Abstract

We consider the problem of slotted asynchronous coded communication, where in each time frame (slot), the transmitter is either silent or transmits a codeword from a given (randomly selected) codebook. The task of the decoder is to decide whether transmission has taken place, and if so, to decode the message. We derive the optimum detection/decoding rule in the sense of the best trade-off among the probabilities of decoding error, false alarm, and misdetection. For this detection/decoding rule, we then derive single-letter characterizations of the exact exponential rates of these three probabilities for the average code in the ensemble.

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Neri Merhav. 2013-08-21. Codeword or noise? Exact random coding exponents for slotted asynchronism. https://arxiv.org/abs/1308.4572

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