A Mote-in-the-Loop Approach for Exploring Communication Strategies for Sensor Networks

Sensor networks are being deployed in a range of different environments, such as industry plants, rainforests and offices. Each environment has its own characteristics and the appropriate communication strategy will differ accordingly – packet sizes, retransmission schemes, error correcting codes, etc. It is, however, difficult to investigate the most appropriate communication strategies for the environment of an intended deployment. On the one hand, simulations are seldom realistic enough as they do not model the environment in every intricate detail. On the other hand, real-world experiments with deployed nodes are important but time-consuming, difficult to repeat, and to some extent dependent on hardware and software. For example, a bug in the software might make measurements collected during an extensive time useless. We need an easier way of testing which still captures realistic communication environments and provides repeatability. We propose a new approach to investigate communication strategies. Our approach uses a combination of on-site radio channel and interference measurements, real sensor network hardware as well as a signal analyser and a signal generator. The advantage of our approach is that once the channel measurements are made, we have a deterministic and repeatable way of investigating the most suitable communication strategy in the lab and for different sensor node hardware. Additionally, we can quickly test new hardware and new implementations by simply recording new packets.