超声编码激励产生声辐射力的数值模拟

摘要

A coded excitation method in ultrasonic elastography, based on the spread spectrum technology, was proposed. A statistical model for the shear wave distribution in the ultrasound field was set up. The theoretical analysis as well as the computer simulation shows that using a coded excitation for the system resources it is more efficient than using a pulsed excitation. Combining the detection technology with coded pulses using different codes for sharewave excitation and the detection, a lower cross-correlation can be achieved so that both the duty cycle of the excitation and the signal-to-noise ratio of the detection can be improved for the whole system.%基于编码扩谱原理,在超声弹性成像技术中,提出用编码激励产生声辐射力的方法,分析其原理并建立了概率统计模型,研究编码激励在各向同性均匀介质中产生的超声剪切波的分布特性.数值仿真结果表明,用编码脉冲激励产生声辐射力的方法可提高系统的时间和频宽利用率,同时结合脉冲超声检测编码调制技术的支持,可减少对激励信号占空比的局限,提高声辐射的穿透力和回波信噪比.