Study Of Surface Acoustic Wave Sensor And Interface Design

Surface acoustic wave (SAW) technology has been applied in many areas, such as electronic communication, wireless remote sensing, and sensor detection. As a multi-function sensor, SAW sensor is widely used in sensitive detection of physical, chemical and biological measurands, having advantages of high sensitivity, small volume and low power consumption. SAW sensing detection technique has good future applications..This dissertation begins with acoustic principle of SAW, and gives a brief introduction of SAW sensing mechanics. Materials and fabrication technology of SAW sensor are also involved.. More attention is paid to analysis of SAW IDT simulation, including δ function model, equivalent circuit model and Coupling-of-Modes model, and perturbation effect theory on sensor surface as well. Depending on these theories and research, we develop a dual channel shear-horizontal surface acoustic wave (SH-SAW) sensor based on 36°-YX LiTaO₃ substrate with 52 MHz and 104 MHz center frequency, and describe the SAW senor interface circuit design in detail. Finally, a network analyzer, Agilent 4395A, is used as a test tool. The results show that the design of SAW sensor and interface circuit reached our expectation. The integration of both SAW sensor and interface circuit is advanced design technique at home, which makes them work in good function and stability.The research work above lays solid foundation for approaches both in frequency stability and spreading and application of SAW sensor in the future.