Speckle reduction in pulse-echo ultrasonic imaging using a two-dimensional receiving array

An experimental pulse-echo imager was developed for the purpose of reducing speckle in ultrasonic images. The system utilized a 64-element spherically focused segmented annuli array receiver with a common transmitter. Compounded images were formed using subapertures of varying size, shape, and overlap, and the speckle and resolution characteristics of the final images were observed. A pointlike scatterer was imaged to determine the resolution, point spread function, and sensitivity of the system along with a new measure called the resolution cell size. The response of the system was also simulated for comparisons. It was found that lateral resolution, and resolution cell sizes only gradually increased with a decrease in subaperture size and system sensitivity was not greatly diminished. Incoherent summation of signals from small groups of elements decreased the speckle noise by a factor of four while maintaining enough resolution to improve the image quality as measured by the CSR/d by a factor of almost two.<<ETX>>

[1]  S.W. Smith,et al.  The Maltese Cross Processor: Speckle Reduction for Circular Transducers , 1988, Ultrasonic imaging.

[2]  G E Trahey,et al.  A Quantitative Approach to Speckle Reduction via Frequency Compounding , 1986, Ultrasonic imaging.

[3]  O. T. von Ramm,et al.  Speckle Reduction In Medical Ultrasound Via Spatial Compounding , 1986, Other Conferences.

[4]  C. Meyer,et al.  Fast Envelope Detection for Thinned Display of Finely Digitized Ultrasound Scans , 1985, IEEE Transactions on Biomedical Engineering.

[5]  C.R. Meyer,et al.  Error Reduction in Through Transmission Tomography Using Large Receiving Arrays with Phase-Insensitive Signal Processing , 1984, IEEE Transactions on Sonics and Ultrasonics.

[6]  F. Foster,et al.  The Improvement and Quantitative Assessment of B-Mode Images Produced by an Annular Array/Cone Hybrid , 1983 .

[7]  R. F. Wagner,et al.  Statistics of Speckle in Ultrasound B-Scans , 1983, IEEE Transactions on Sonics and Ultrasonics.

[8]  O. V. von Ramm,et al.  Delay Quantization Error in Phased Array Images , 1981, IEEE Transactions on Sonics and Ultrasonics.

[9]  S.W. Smith,et al.  A multiple frequency array for improved diagnostic imaging , 1978, IEEE Transactions on Sonics and Ultrasonics.

[10]  Mauri Luukkala,et al.  The impulse response and pressure nearfield of a curved ultrasonic radiator , 1976 .

[11]  P. Stepanishen.  Transient Radiation from Pistons in an Infinite Planar Baffle , 1970 .

[12]  Paul L. Carson,et al.  Micromachining for improvement of integrated ultrasonic transducer sensitivity , 1990 .

[13]  R.L. Galloway,et al.  A frequency diversity process for speckle reduction in real-time ultrasonic images , 1988, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[14]  P. Carson,et al.  A Two-Dimensional Array Receiver for Reducing Refraction Artifacts in Ultrasonic Computed Tomography of Attenuation , 1987, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[15]  J.G. Miller,et al.  Phase-Insensitive Detection for Measurement of Backscattered Ultrasound , 1986, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[16]  S.W. Smith,et al.  Speckle Pattern Correlation with Lateral Aperture Translation: Experimental Results and Implications for Spatial Compounding , 1986, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[17]  P. Carson,et al.  Directivity and Sensitivity with Phase-Insensitive Arrays Used for Ultrasonic Measurements of Tissue Characteristics , 1986, IEEE 1986 Ultrasonics Symposium.

[18]  C. Burckhardt.  Speckle in ultrasound B-mode scans , 1978, IEEE Transactions on Sonics and Ultrasonics.

[19]  J. G. Abbott,et al.  Multi-Scan Processing in a Phased Array Imaging System , 1978 .