Abstract:In order to improve the imaging quality and efficiency of synthetic aperture focusing technique (SAFT), a frequency domain SAFT ultrasonic imaging algorithm based on phase circular statistics vector (PCSV) is proposed. Firstly, the Hilbert transform and Euler′s formula are used to extract the instantaneous phase of the signals in wave field record. Secondly, the real part and imaginary part of the instantaneous phase are regarded as the PCSVs distributed in circular complex plane, and through wave field extrapolation, the phase coherence factor used for frequency domain SAFT weighting is constructed. Finally, the high quality frequency domain SAFTPCSV image is obtained through weighting processing. The imaging results show that the frequencydomain SAFTPCSV imaging algorithm effectively enhances the image resolution and signaltonoise ratio. Under the same test conditions, the operational time and occupied memory space of the frequencydomain SAFTPCSV imaging algorithm are less than 1/46, and 1/47 of those of traditional timedomain SAFT algorithm, respectively.