Chen Quan, Gerig Anthony L, Techavipoo Udomchai, Zagzebski James A, Varghese Tomy
Department of Medical Physics, The University of Wisconsin-Madison, Madison, WI-53706, USA.
IEEE Trans Ultrason Ferroelectr Freq Control. 2005 Jun;52(6):961-70. doi: 10.1109/tuffc.2005.1504018.
A theoretical analysis of the correlation between radio-frequency (RF) echo signal data acquired from the same location but at different angles is presented. The accuracy of the theoretical results is verified with computer simulations. Refinements to previous analyses of the correlation of RF signals originating from the same spatial location at different angular positions are made. We extend the analysis to study correlation of RF signals coming from different spatial locations and eventually correlation of RF signal segments that intersect at the same spatial location. The theory predicts a faster decorrelation with a change in the insonification angle for longer RF echo signal segments. As the RF signal segment becomes shorter, the decorrelation rate with angle is slower and approaches the limit corresponding to the correlation of RF signals originating from the same spatial location. Theoretical results provide a clear understanding of angular compounding techniques used to improve the signal-to-noise ratio in ultrasonic parametric imaging and in elastography.
本文对从同一位置但不同角度获取的射频（RF）回波信号数据之间的相关性进行了理论分析。通过计算机模拟验证了理论结果的准确性。对先前关于在不同角位置源自同一空间位置的RF信号相关性分析进行了改进。我们扩展了分析范围，以研究来自不同空间位置的RF信号的相关性，最终研究在同一空间位置相交的RF信号段的相关性。该理论预测，对于较长的RF回波信号段，随着声束入射角的变化，去相关速度会更快。随着RF信号段变短，角度去相关速率变慢，并接近源自同一空间位置的RF信号相关性对应的极限。理论结果为用于改善超声参数成像和弹性成像中信噪比的角度复合技术提供了清晰的理解。
