Evaluation of a Low-Cost IEEE 802.11n MIMO Testbed

This paper presents and evaluates a configurable and inexpensive MIMO mesh network platform based on IEEE 802.11n and open source software for research purposes. The requirements on such a research testbed are twofold. On the one hand a highly configurable solution is desirable where the researcher is able to make modifications on each layer of the hardand software solution. On the other hand to make sound conclusions on the performance of protocols for mesh networks a large-scale testbed consisting of hundreds of nodes is necessary. Therefore, a single mesh node has to be inexpensive. Thus a tradeoff between these two opposed targets has to be made. The proposed solution is based on off-the-shelf 802.11n hardware using Atheros WiFi chips together with the open source WiFi driver ath9k and the Click Router API. This solution represents a good tradeoff where the procurement cost for a network node is below 100 $ while still allowing a variety of adjustments to be made due to the used open-source driver and a highly configurable WiFi hardware. With the help of measurements, the suitability of the platform is evaluated.