摘要
利用时间反转法对相控阵高强聚焦超声系统进行自适应聚焦,需要计算出各阵元的初始发射相位。锁相环电路初始工作时频率有震荡,用常规计算相位差的方法当截取数据的时间段不同时计算出的相位差不相同。提出一种计算相位差的方法,可以实时显示相位差的变化,将稳定后的相位差作为相控阵聚焦系统各发射阵元的初始相位。实验结果表明,用此方法计算的相位差进行聚焦可以在一定空间范围内得到较好的声场分布。
When time reversal technique is used in phased array high intensity focused ultrasound system to obtain self-adaptive focusing, it is needed to calculate the initial phase of the sources. Because of the frequency shifting when the phase lock loop is initiated, different results are gotten in different segments using conventional methods. A new method of calculating the phase difference is presented. Because it can display the changes of phase difference in real-time, the steady phase differences can be regarded as the initial phase of the sources. The experimental results show that using the phase difference obtained by this method can get a better distribution of sound field in some spatial extent.
出处
《声学学报》
EI
CSCD
北大核心
2010年第3期303-308,共6页
Acta Acustica
基金
国家自然科学基金(60970136)
中国科学院知识创新工程重要方向(KGCX2-YW-914)资助项目
