基于水下超声成像分时复用数据采集系统的设计

利用压阻式水声传感器采集超声回波信号,通过行共用电源线,列共用信号线的方式将水声传感器组成成像阵列.使用MAX4617八选一高速模拟开关控制每个传感器与采集电路的通断,从而实现采集电路的分时复用功能.利用AD6655采集数据,FPGA作为模拟开关和采集电路的时序控制器,异步FIFO作为采集数据传送给EZ-USB的缓冲器,EZ-USB单片机负责任务的协调,并把数据打包上传给计算机.初步测试了传感器与采集通道的开关时延特性,以及分时采集样本与原始声信号吻合程度,实验结果证明系统能够完成水声传感阵列的实时数据采集任务.

Design of Time Division Data Acquisition System Based on Underwater Acoustic Imaging

This paper used piezoresistive underwater acoustic transducer for acquisition ultrasonic echo.It made up transducer array for imaging via sharing power line in horizontal row and signal line in vertical row.It used MAX4617 8×1 high speed analog switch for controlling open or close between transducer and acquisition circuit to realize the function of time division multiplexing.AD6655 was used for acquiring data.FPGA was used for controlling analog switch and acquisition circuit.FIFO was buffer between EZ-USB and AD6655.EZ-USB microprocessor assigned works and transmitted data to PC by package.The performance of the open and close between transducer and acquisition channel,and test agreement between original signal and data acquired by time division were tested.The results show that the system can achieve real-time acquisition of the acoustic signal by sonar array.