A Scheme to Compensate Time Drift in Time Difference of Arrival Localization Among Non-Synchronized Sensor Nodes

Ranging and localization are some of the key applications in a wireless sensor network. Good accuracy can be obtained if the signals captured are of good qualities. In a practical scenario, crystal clock timing drift in the devices in a wireless sensor network will greatly influence the ranging and localization accuracy. In this paper, we shall use Time Difference of Arrival technique to determine the locations of the devices. In particular, we will highlight the importance of time drift in affecting the accuracy of location determinations and proposed a scheme to overcome time drift when performing Time Difference of Arrival localization. In addition, we will also estimate the devices transmit time offset so that we can compensate this value from the range information. In this way, there is no requirement for the sensor nodes to be synchronized initially.