Investigation of methods to extract TDOA from UWB-IR waveforms

By using the Time-Difference-of-Arrival (TDOA) of UWB-IR waveforms at multiple antennas, the position of a transmitting tag can be accurately estimated for high precision positioning applications. Several methods can be used to obtain the TDOA information based on the knowledge of the received waveforms at the antennas. The performance of the various methods however depend on the quality of the received signals. In this paper, the performance of some of the methods (peak detection, leading edge detection, envelope detection, cross correlation detection and use of template waveforms) are experimentally evaluated by using them to derive the TDOA information from the measured waveforms. The derived TDOA information is compared with the actual TDOA and from there, the strengths and weaknesses of each method are discussed.