On the Enhanced Ranging Performance for IEEE 802.15.4 Compliant WSN Devices

In the wireless sensor networks (WSNs) context, accurate and efficient ranging is an important factor to consider in order to enhance the demand of future emerging location aware applications. To enhance ranging accuracy, processing a large number of ranging samples to reach a true average range estimate is a common strategy at the cost of extra computation. At the same time, due to the noisy background and interference, there is a chance that some packets or acknowledgments (ACKs) will get corrupted on air and not be received, hence corrupting the ranging samples and degrading the ranging accuracy. This paper evaluates the impact of a noisy channel on time-of-flight (ToF) and received signal strength (RSS) ranging performance. The motivation behind this is not only to enhance the ranging accuracy but also to keep the energy consumption as low as possible by processing the minimum successful ranging polls to comply with the WSNs constraints. A series of experiments were conducted in two different environments to ascertain which system parameters lead to improved performance and successful ranging polls.