Robust TDOA/FDOA estimation from emitter signals for hybrid localization using UAVs

Abstract

This paper considers the time difference of arrival (TDOA) and frequency difference of arrival (FDOA) estimation problem for joint localization using unmanned aerial vehicles (UAVs), involving range migration (RM) and Doppler ambiguity within observation interval. A robust estimation method based on interpolation and resampling is proposed. Specifically, the interpolation artificially increases the pulse repetition frequency (PRF). After that, the resampling eliminates the coupling between range frequency and slow time. Finally, a coherent integration step based on inverse discrete Fourier transform (IDFT) is used to achieve parameter estimation and suppress the grating lobes caused by interpolation. The proposed method could be efficiently implemented by fast Fourier transform (FFT), inverse FFT (IFFT) and non-uniform FFT (NUFFT) without parameter searching procedures. Numerical experiments indicate that the proposed method has nearly optimal anti-noise performance but much lower computational complexity than the maximum likelihood estimator, which makes it more competitive in practical applications.

Keywords

• TDOA
• FDOA
• Parameter estimation
• Doppler ambiguity
• Hybrid localization