基于WIFI的无线声表面波传感器信号采集系统

将声表面波传感器与信号无线保真(WIFI)技术相结合,提出了一种基于WIFI的无线声表面波传感器信号采集系统.该系统由声表面波传感器、信号调理电路、处理器、WIFI模块和无线接收终端组成.声表面波传感器混频后的信号经过信号调理电路后,转换为处理器可计频的低频方波信号,并通过WIFI模块将采集到的信号无线发送到接收终端.通过一个输出信号范围在100 kHz~350 kHz声表面波传感器信号采集系统的实现,对该系统的结构、性能进行了验证和测试.实验结果表明,该系统可以实现测试范围内信号的采集、发送和无线接收,系统输入信号与无线接收终端接收信号之间的平均绝对误差为0.843 kHz,最大相对误差为0.51%,无障碍环境有效采集范围约为100 m,有障碍环境有效采集范围约为50 m.

Wireless SAW sensor signal acquisition system based on the WIFI

The signal wireless fidelity(WIFI)technology is incorporated into the surface acoustic wave(SAW)sen-sor,and the wireless SAW sensor signal acquisition system based on the WIFI is proposed. The system consists of the SAW sensor,the signal conditioning circuits,the processors,the WIFI module and the wireless receiver termi-nal. The mixed SAW sensor signal is converted into the low frequency square wave signal by the signal conditioning circuit. The low frequency square wave signal can be counted by the processor and the collected signal data is trans-mitted to the receiving terminal by the WIFI module wirelessly. The structure and performance of the SAW sensor signal acquisition system based on the WIFI is validated and tested by means of the SAW sensor signal acquisition system with the output frequency range from 100 kHz to 350 kHz. Experimental results show that the signal can be collected,transmitted and received wirelessly within the test range. The average absolute error with input signal and the received signal is about 0.843 kHz,and the maximum relative error is about 0.51%. The effective acquisition range is about 100 meters in the barrier-free environment and about 50 meters in the obstacle environment.