Research of TDOA Based Self-localization Approach in Wireless Sensor Network

Sensor network, which has integrated wireless communication, date collection and information processing capacities, is a booming technique in information collecting. With the development of research on wireless sensor networks (WSNs), localization in the WSNs has become a very important research point. At present, there are mainly two kinds of approaches, range-based approach and range-free approach. Localization precision of range-based approach is higher than the range-free approach. In the range-based approach, time difference of arrival (TDOA) method needs less requirements for time synchronization. This paper proposes a self-localization approach based on TDOA, which utilizes average value of time difference by rolling average to decrease the measurement error, and adopts unconstrained least squares (LS) estimator to achieve the accurate localization. Simulation results and error analysis prove its validity