超声相控阵检测是通过控制超声波的相位延时实现声束偏转聚焦，继而完成探测被测试件内部缺陷的技术，因此相位延时精度是此技术的关键所在。因现场可编程门阵列(FPGA)芯片具有复杂而强大的时序功能，故系统的设计基于FPGA芯片，利用锁相环的倍频和移相技术，采用同步和等延时设计，最终实现了1 ns的阵元发射延时精度。同时，设计使用嵌入式处理器，实现延时时间、激励信号的周期及重复频率的可重配置功能。Modelsim软件的仿真结果，验证了设计的可行性和正确性。

By controlling the phase delay of ultrasound，ultrasonic phased array inspection technology achieves beam deflection and focus, then detects internal defects. So the phase delay accuracy is the key to this technology. The FPGA chip has complex and powerful timing functions and meets ultrasonic phased array delay control needs. Through a phase-locked loop frequency multiplier and phase shift, the system adopts synchronization and latency design, and reaches 1 ns delay resolution. Simultaneously, processor achieves parameters reconfiguration function, and those parameters are the delay time and cycle and repetition frequency of the excitation signal. Modelsim software simulation results verify the feasibility and correctness of the design.