相控阵超声接收动态聚焦算法及其物理实现

Receiving dynamic depth focusing algorithm of phased array ultrasound imaging and its physical implementation scheme

本文提出一种新的相控阵接收动态聚焦的实现方案,在传统的单接收聚焦点接收的基础上,把各换能器单元接收信号的补偿位置计算出来,在各通道数据叠加前将数据动态补偿,实现各个采样点都接收动态聚焦。在工程上,实际检测深度有一定范围限制,补偿点数其实并不是太大,所以方法具有可实现的条件。并且在计算补偿点时,可以使用楔块折射后的声波传播路径,使在折射的条件下也可成功动态聚焦。本文提供了计算补偿点的方法,最后给出了计算机仿真对比和物理实现方案,仿真结果可以看出成像效果与传统单点聚焦相控阵对比有了显著提高。提出的动态聚焦的方法很大地改善了成像质量,方法具有实用价值。

A new scheme of dynamic depth focusing（ DDF） in phased array imaging is proposed in this paper. Based on the conventional process of transmitting and receiving with single depth focus,the echo signals each elements received are dynamically compensated in the special positions in order to focus in all depths. All the compensation positions can be calculated out and saved in an array. This paper provides the algorithm for calculating the compensation positions,which fits in all conditions including the situation of refraction at the interface. The computer simulation results show that the proposed scheme provides a significantly improved lateral resolution at all depths compared to the conventional one. The proposed scheme improved the resolution significantly. And it has practical value.