Optimal routing, link scheduling and power control in multihop wireless networks

TLDR

The study seeks to jointly optimize routing, link scheduling, and power control in broadband wireless multihop networks to achieve high data rates while minimizing average transmission power under rate and power constraints. The authors model multiaccess interference, apply a duality‑based optimization that yields optimal power and scheduling policies and their sensitivities, and exploit the convexity of total power to use shortest‑path algorithms for globally optimal routing. Experiments demonstrate that the algorithm can achieve data rates unattainable by conventional methods and that optimal allocations may avoid minimum‑energy paths.

Abstract

In this paper, we study the problem of joint routing, link scheduling and power control to support high data rates for broadband wireless multihop networks. We first address the problem of finding an optimal link scheduling and power control policy that minimizes the total average transmission power in the wireless multihop network, subject to given constraints regarding the minimum average data rate per link, as well as peak transmission power constraints per node. Multiaccess signal interference is explicitly modeled. We use a duality approach whereby, as a byproduct of finding the optimal policy, we find the sensitivity of the minimal total average power with respect to the average data rate for each link. Since the minimal total average power is a convex function of the required minimum average data rates, shortest path algorithms with the link weights set to the link sensitivities can be used to guide the search for a globally optimum routing. We present a few simple examples that show our algorithm can find policies that support data rates that are not possible with conventional approaches. Moreover, we find that optimum allocations do not necessarily route traffic over minimum energy paths.