TDMA Scheduling in Long-Distance WiFi Networks

In the last few years, long-distance WiFi networks have been used to provide Internet connectivity in rural areas. The strong requirement to support real-time applications in these settings leads us to consider TDMA link scheduling. In this paper, we consider the FRACTEL architecture for long-distance mesh networks. We propose a novel angular interference model, which is not only practical, but also makes the problem of TDMA scheduling tractable. We then consider delay-bounded scheduling and present an algorithm which uses at most 1/3rd more time-slots than the optimal number of slots required without the delay bound. Our evaluation on various network topologies shows that the algorithm is practical, and more efficient in practice than its worst-case bound.