THE APPLICATION OF K-SPACE IN PULSE-ECHO ULTRASOUND

K-space is a frequency domain description of imaging systems and targe ts that can be used to gain insight into image formation. Although ori ginally proposed in ultrasound for the analysis of experiments involvi ng anisotropic scattering and for the design of acoustic tomography sy stems, it is particularly useful for the analysis of pulse echo ultras onic imaging systems. This paper presents analytical and conceptual te chniques for estimating the k-space representation of pulse echo imagi ng systems with arbitrary transmit and receive array geometries and ap odizations. Simple graphical methods of estimating the first and secon d order statistics of speckle are presented. Examples are presented th at utilize k-space to gain insight regarding the performance of spatia l and frequency compounding and to describe the impact of synthetic re ceive aperture geometry on beamforming and speckle statistics. The Van Cittert-Zernike theorem is presented in k-space, and techniques for i mproving echo coherence are discussed.