2016/12/20 by Sergey Loyka, Loyka, Sergey, Charalambos D. Charalambous +1
Computer Science · Engineering · #Distributed Sensor Networks and Detection Algorithms #Energy Harvesting in Wireless Networks #FOS: Computer and information sciences #Information Theory (cs.IT) #Wireless Communication Security Techniques
paper · pdf · doi:10.48550/arxiv.1612.06900
openalex publication_date 2016/12/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A discrete compound channel with memory is considered, where no stationarity,\nergodicity or information stability is required, and where the uncertainty set\ncan be arbitrary. When the discrete noise is additive but otherwise arbitrary\nand there is no cost constraint on the input, it is shown that the causal\nfeedback does not increase the capacity. This extends the earlier result\nobtained for general single-state channels with full transmitter (Tx) channel\nstate information (CSI) to the compound setting. It is further shown that, for\nthis compound setting and under a mild technical condition on the additive\nnoise, the addition of the full Tx CSI does not increase the capacity either,\nso that the worst-case and compound channel capacities are the same. This can\nalso be expressed as a saddle-point in the information-theoretic game between\nthe transmitter (who selects the input distribution) and the nature (who\nselects the channel state), even though the objective function (the\ninf-information rate) is not convex/concave in the right way. Cases where the\nTx CSI does increase the capacity are identified.\n Conditions under which the strong converse holds for this channel are\nstudied. The ergodic behaviour of the worst-case noise in otherwise\ninformation-unstable channel is shown to be both sufficient and necessary for\nthe strong converse to hold, including feedback and no feedback cases.\n