On the use of multiple emitters to improve the TDOA source localization accuracy in the presence of random sensor position errors

Abstract

It is known that random sensor position errors can significantly degrade the TDOA source localization accuracy. In this thesis, we conduct a systematic study on using the calibration emitters to mitigate the effect of random sensor position errors. Four localization scenarios are considered. They are (i) locating a single source with a calibration emitter at accurate location; (ii) locating a single source with calibration emitters at inaccurate locations; (iii) locating multiple disjoint sources in the presence of random sensor position errors; and (iv) tracking a single moving source while simultaneously calibrating sensor positions. Note that scenario (iii) includes the problem of locating a source with calibration emitters at completely unknown locations as a special case. Moreover, scenario (iv) can be viewed as the extension of scenario (iii) in the sense that the unknown source positions are now generated by a moving source. For each localization scenario, we investigate the amount of performance improvement in terms of TDOA source localization accuracy brought by the use of the calibration emitters via deriving the corresponding CRLB of the source positions. More importantly, we propose novel source localization algorithms that can explore the TDOA measurements from the calibration emitters to reduce the effect of random sensor position errors. Theoretical performance analysis is conducted to show that the proposed localization algorithms are all able to reach the CRLB accuracy under mild conditions. Extensive simulation results are provided to corroborate the theoretical developments.