On the Unicast Capacity of Stationary Multi-channel Multi-radio Wireless Networks: Separability and Multi-channel Routing

TL;DR

This paper investigates the capacity of stationary multi-channel multi-radio wireless networks, analyzing when capacities are additive across channels and how multi-channel routing influences overall network capacity.

Contribution

It establishes conditions under which the unicast capacity is separable and shows the equivalence of routing schemes when the number of radios equals channels.

Findings

Separable capacity holds when radios equal channels.

Multi-channel routing does not always increase capacity.

Capacity equivalence under routing schemes when radios equal channels.

Abstract

The first result is on the separability of the unicast capacity of stationary multi-channel multi-radio wireless networks, i.e., whether the capacity of such a network is equal to the sum of the capacities of the corresponding single-channel single-radio wireless networks. For both the Arbitrary Network model and the Random Network model, given a channel assignment, the separability property does not always hold. However, if the number of radio interfaces at each node is equal to the number of channels, the separability property holds. The second result is on the impact of multi-channel routing (i.e., routing a bit through multiple channels as opposed to through a single channel) on the network capacity. For both network models, the network capacities conditioned on a channel assignment under the two routing schemes are not always equal, but if again the number of radio interfaces at each node is equal to the number of channels, the two routing schemes yield equal network capacities.