Instantaneous Frequency Extraction in Dynamic Frequency Scanning Interferometry Based on a Frequency Shift Adaptive Wavelet

In dynamic frequency scanning interferometry, the interference signal frequency is modulated from the target so that the instantaneous interference signal frequency contains dynamic motion information about the target to be measured. Accurately extracting the instantaneous interference signal frequency is a crucial solution step for dynamic target measurement. To address the narrowband frequency modulation and wideband frequency modulation introduced by different degrees of vibration, we propose a method that combines orthogonal interference with a wideband frequency shift adaptive wavelet (WFS-AW) to extract instantaneous frequencies. In addition, this method corrects the quadrature phase error to ensure signal orthogonality. The simulation results verify the effectiveness and stability of the algorithm proposed in this article in accurately extracting the instantaneous interference signal frequency. The final experimental results show that this method achieves dynamic target measurement of broadband frequency modulation interference signals.