双通道结构SAW压力传感器测量电路设计  

Design of measuring circuit of SAW pressure sensor with dual channel structure

作　　者：蒋建伟 蒋华[1] 郭兴龙[1] Jiang Jianwei;Jiang Hua;Guo Xinglong(School of Information Science and Technology,Nantong University,Nantong 226019,China)

机构地区：[1]南通大学信息科学技术学院,南通226019

出　　处：《国外电子测量技术》2022年第8期181-187,共7页Foreign Electronic Measurement Technology

基　　金：国家自然科学基金(62074086)项目资助。

摘　　要：针对声表面波(SAW)传感器输出的模拟信号难以准确变换和处理的问题,提出了延迟线型SAW压力传感器等效电路模型,设计了一种双通道结构模数混合测量电路,包括改进的SAW振荡器、混频器、低通滤波器、整形器、单片机等。通过ADS和Multisim仿真验证了测量电路的功能,其中改进的SAW振荡器中心频率为40MHz,采用双通道结构混频后,经过低通滤波器输出频率为1kHz的正弦波,再经过整形器将正弦波转换成频率为1kHz的方波。相对于单通道高频振荡信号,该测量电路不仅输出频率更准确,而且将高频模拟信号转换为低频数字信号更易于采用单片机处理。In order to solve the problem that it is difficult to accurately transform and process the analog signal output by surface acoustic wave(SAW) sensor. The equivalent circuit model of delay line SAW pressure sensor is proposed, and a dual channel analog-to-digital hybrid measurement circuit is designed, including improved SAW oscillator, mixer, low-pass filter, shaper, single chip microcomputer and so on. The function of the measuring circuit is verified by ADS and Multisim simulation. The center frequency of the improved SAW oscillator is 40 MHz. After mixing with the dual channel structure, the sine wave with the frequency of 1 kHz is output through the low-pass filter, and then the sine wave is converted into a square wave with the frequency of 1 kHz through the shaper. Compared with the single channel high-frequency oscillation signal, the measuring circuit not only outputs the frequency more accurately, but also converts the high-frequency analog signal into low-frequency digital signal, which is easier to be processed by single chip microcomputer.

关 键 词：SAW振荡器 SAW压力传感器 双通道结构 测量电路 

分 类 号：TP212.6[自动化与计算机技术—检测技术与自动化装置]