A Newton Iteration Based WSN Localization System in Underground Tunnels
One of the main concerns in under construction tunnels is ensuring the safety of the workers and their equipment. Being aware of the real-time position of personnel in such harsh environment is challenging and usually requires a sophisticated localization system. With traditional Received Signal Strength Indicator (RSSII) failing to accurately estimate the distance between nodes due to multipath effect in such long and narrow space, Radio Frequency Time-of-Flight (RF-TOF) is proved to be an alternative method for more accurate distance estimation. To reduce the communication cost, a distributed localization system is proposed, where a simple Newton Iteration location estimation algorithm is embedded in the blind node. Linear least square estimation is used as the initial value to accelerate the convergence of the iteration. Experimental results show the effectiveness of the proposed system