The existence of regularly spaced scatterers in the range cell of an ultrasonic imaging system results in speckle with a nonuniform phase distribution. Characteristic phase distributions occur at those particular demodulator frequencies at which the spacing is a multiple of one-quarter wavelength. A demodulator frequency sweeping technique for scatterer spacing estimation has been developed that uses parametric expressions of the phase statistics to detect and to identify scatterers with regular spacings. Changes in these parameters separately identify the mean scatterer spacing when it is an even and an odd multiple of the quarter wavelength of the demodulator frequency. This technique has good tolerance for variations in mean scatterer spacing, and has real-time implementation capability.
|ジャーナル||IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control|
|出版ステータス||Published - 1992 5|
ASJC Scopus subject areas
- Acoustics and Ultrasonics
- Electrical and Electronic Engineering