Compound Multiple Access Channels with Partial Cooperation

TL;DR

This paper characterizes the capacity regions of compound multiple access channels with partial cooperation, providing achievable rates and extending results to Gaussian models, highlighting potential gains from conferencing.

Contribution

It offers new capacity region characterizations for channels with partial cooperation, including special cases and extensions to Gaussian models, and compares different cooperation models.

Findings

Capacity regions are characterized for special cases.

Achievable rates are within a constant gap of the capacity boundary.

Numerical results illustrate potential gains from cooperation.

Abstract

A two-user discrete memoryless compound multiple access channel with a common message and conferencing decoders is considered. The capacity region is characterized in the special cases of physically degraded channels and unidirectional cooperation, and achievable rate regions are provided for the general case. The results are then extended to the corresponding Gaussian model. In the Gaussian setup, the provided achievable rates are shown to lie within some constant number of bits from the boundary of the capacity region in several special cases. An alternative model, in which the encoders are connected by conferencing links rather than having a common message, is studied as well, and the capacity region for this model is also determined for the cases of physically degraded channels and unidirectional cooperation. Numerical results are also provided to obtain insights about the potential gains of conferencing at the decoders and encoders.