Efficient Receive Diversity in Distributed Sensor Networks Using Selective Sample Forwarding
Muhammad Nabeel, Bastian Bloessl, Falko Dressler · IEEE Transactions on Green Communications and Networking · 2017
We study the potential of exploiting receive diversity in a distributed wireless sensor network (WSN). In contrast to other approaches, we fully rely on diversity combining on signal level by introducing selective sample forwarding to a centralized receiver. That way, we use the WSN as a distributed antenna array and still take the rather limited data rates between the sensor nodes into consideration. In particular, we consider a distributed ground network in the wild to track bats in their natural habitat. The bats are equipped with a sensor node of only 2 g, which limits the energy budget available for communication. The main challenges to be addressed are the limited bandwidth between nodes and the need for accurate time synchronization to combine signal copies constructively at a central node. We study the performance based on a GNU Radio implementation both in simulations as well as in laboratory experiments. Our results clearly indicate a substantial performance gain while keeping the data rate in the distributed sensor network in a feasible range.