无线无源谐振式传感器读取单元的设计与研究

摘要

Based on mutual inductance coupling principle of LC resonant sensor, the novel readout unit on the basis of ASIC dedicated analog IC test module is researched and designed. The theoretical model of frequency readout method for wireless passive LC resonant sensor is expounded, the circuit structure for generating sweep frequency signal using the module is introduced, and the test method that combining digitized storage and PC post-processing is described in detail. The experimental results indicate that when the distance between sensor and readout antenna is 2. 5 cm, and the pressure range within 0 to 0. 3 MPa, the resonant frequency measured by the readout unit and the data read from impedance analyzer is consistent, the maximum relative error is 5. 36%, this provides possibility for applying wireless passive LC resonant sensor in practical engineering environment outside laboratories.%基于LC谐振传感器的互感耦合原理，研究并设计了一种基于ASIC的专用模拟集成电路测试模块的新颖读取单元。论述了无线无源LC谐振传感部分频率读取方法的理论模型，介绍了利用该模块产生扫频信号的电路结构，并详细阐述了数字化存储与PC后处理结合的测试方法。实验结果表明，传感器与读取天线的耦合距离为2.5 cm时，在0~0.3 MPa的压力范围内，使用该读取单元测得的传感器谐振频率与阻抗分析仪读取的数据表现出良好的一致性，最大相对误差为5.36%。该读取单元为无线无源LC谐振传感器应用于实验室以外的实际工程环境提供了可能。