Two results on the permuting mailbox channel

Two problems of information transmission on the permuting mailbox (or relay) channel are considered. Such a channel is characterized by the cardinality epsilon of the alphabet and the number b of letters in the mailbox. In the case b=1, an upper bound is obtained on the achievable rate in the jamming situation. In the case epsilon =2, it is proven that time-sharing is not always the best solution when both main users wish to transmit information to a third user.<
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