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This work addresses the cooperation facilitator (CF) model, in which network nodes coordinate through a rate limited communication device. For multiple-access channel (MAC) encoders, the CF model is known to show significant rate benefits, even when the rate of cooperation is negligible. Specifically, the benefit in MAC sum-rate, as a function of the cooperation rate C_{CF}, sometimes has an infinite slope at C_{CF} = 0 when the CF enables transmitter dependence where none was possible otherwise. This work asks whether cooperation through a CF can yield similar infinite-slope benefits when dependence among MAC transmitters has no benefit or when it can be established without the help of the CF. Specifically, this work studies the CF model when applied to relay nodes of a single-source, single-terminal, diamond network comprising a broadcast channel followed by a MAC. In the relay channel with orthogonal receiver components, careful generalization of the partial-decode-forward/compress-forward lower bound to the CF model yields sufficient conditions for an infinite-slope benefit. Additional results include derivation of a family of diamond networks for which the infinite-slope rate-benefit derives directly from the properties of the corresponding MAC studied in isolation.
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Authenticated Partial Correction Over AV-MACs: Toward Characterization and Coding
In this paper we study $$\gamma$$ partial correction over a $$t$$-user arbitrarily varying multiple-access channel (AV-MAC). We first present necessary channel conditions for the $$\gamma$$ partially correcting authentication capacity region to have nonempty interior. We then give a block length extension scheme which preserves positive rate tuples from a short code with zero probability of $$\gamma$$ partial correction error, noting that the flexibility of $$\gamma$$ partial correction prevents pure codeword concatenation from being successful. Finally, we offer a case study of a particular AV-MAC satisfying the necessary conditions for partial correction.
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- Award ID(s):
- 2107488
- PAR ID:
- 10638833
- Publisher / Repository:
- IEEE
- Date Published:
- ISSN:
- 2836-4503
- Page Range / eLocation ID:
- 1 to 8
- Subject(s) / Keyword(s):
- arbitrarily varying multiple-access channel, capacity region, authentication, partial correction
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/Allerton63246.2024.10735304
