Time Delay Estimation by Bispectrum Interpolation

Time delay is an important parameter for the characterization of signal propagation of sensors. In order to improve the precision of time delay estimation, this article proposes an algorithm based on bispectrum interpolation. The algorithm first calculates the characteristic spectrum function on the basis of the bispectrum of the two signals. The frequency domain interpolation is done on the characteristic spectrum function. By conducting the inverse Fourier transform and the maxima seeking method, the calculation formula for the time delay of the two signals is deduced. The simulation test results show that compared with the bispectrum-based time delay estimation method, the bispectrum interpolation-based time delay estimation method has improved greatly in terms of the estimation precision and temporal resolution. The algorithm has the advantages of high precision, small error and strong ability to suppress the correlative Gaussian noise. [PUBLICATION ABSTRACT]