Comparison of two field simulation models of two-dimensional ultrasound transducer arrays in time domain

Simulation experiments were designed to compare the segmented-element spatial impulse response model and the discrete point-matrix model for acoustic field calculation of two-dimensional transducer array e.g. xMATRIX transducer. Computation ac- curacy, efficiency, influential parameters and suitable application of the two models were analyzed and compared. The experimental results demonstrated that the segmented-element spatial impulse response model is fast and accurate, and it is sensitive to element size, pitch, focus depth and the ratio between height and width of elements. The segmented-element spatial impulse response model is a popular tool to simulate ultrasonic filed in homogeneous medium. The discrete point-matrix model is computed costly when applying to two-dimensional transducer array. Its accuracy is inferior to the segmented-element spatial impulse response model. The discrete point-matrix model depends heavily on the number of elements and their represented points. However, it is convenient to simulate the filed of arbitrarily shaped ultrasound transducer array in inhomogeneous medium. With the same array aperture and excited impulse, accuracy of the segmented-element spatial impulse response model is 6% higher than that of the discrete point-matrix model. Never- theless, its computation cost of two-dimensional and three-dimensional beam distribution is 20 and 1000 times lower than that of the discrete point-matrix model respectively.