Two step UWB TOA estimation method for WSN ranging

Jointing energy detection and match-filter method can speed up the estimation process and perform accurate estimation.In first step,obtained a rough TOA by non-coherent low-rate energy samples.Then,in the second step,estimated a precise TOA of the direct-path(DP)by correlation match-filter within energy sample periods obtained in anterior step.In proposed algorithm,the parameters such as energy sample period and normalized thresholds play important role.So,discussed and modeled their effects based on maximum-to-minimum energy ratio and noise statistics.Simulation results in IEEE 802.15.4a channel demonstrate that the proposed method outperforms the non-coherent energy-detection method,and decreases the computation-quantity comparing to match-filter.So,the proposed method is more appreciate to WSN node.