仿人体组织材料的超声背向散射系数测量研究

材料的背向散射系数是与声速、声衰减系数并列的重要声学参数,常被用于疾病诊断和材料设计.与声速、声衰减系数的测量相比,背向散射系数的测量装置和结果处理较为复杂,迄今国内外并没有统一的标准.本文以仿人体组织材料为研究对象,采用了仿人体组织的超声散射理论模型,建立了脉冲回波法的背向散射系数测量装置;实验研究了水浸聚焦探头焦点位置的选择与背向散射回波信号长度的选择对测量结果的影响.结果表明,探头在物体中的聚焦位置对测量结果影响较小;随着散射回波信号长度的增加,计算得出的散射系数会有所减小,但影响有限.

Measurement of Ultrasonic Backscatter Coefficient in Tissue-Mimicking Material

Backscatter coefficient is one of the important acoustic parameters with velocity and attenuation.It is often used in diagnosis and material design.Compared with velocity and attenuation measurement,backscatter coefficient measurement is more complicated both for equipment and computation.Unified method for backscatter coefficient measurement remains unsolved both in home and abroad.In this work,the author applies the ultrasonic backscatter model and sets up the measurement equipment based on pulse echo mode for a kind of tissue mimicking material.Influences of both ultrasonic focus position and data length on backscatter coefficient measurement are studied by experiments.Results show that the focus position and data length have minor impact on the backscatter coefficient measurement.