Design And Simulation Of Surface Acoustic Wave(SAW) Gas Sensor Integrated System

Using surface acoustic wave propagation and signal processing technology is called surface acoustic wave technology.As a developing technology,surface acoustic wave technology is the combination of acoustics,electronics and materials,and it has been widely used in electronic communication,radar communication,mobile communications,radio frequency identification,and many kinds of sensor systems,which are involved in aviation,aerospace,military and civilian fields.In this paper,design and simulation of the dual channels SAW gas sensor system is done based on the detection principle of SAW gas sensor,and design and simulation of function module circuit of the system is also made in detail,which includes analog circuit and digital circuit.In the research of the analog circuit,we designed oscillation circuits for resonance frequency of 318 MHz commercial SAW device and the frequency of 300 MHz SAW device which we made,and also design the band-pass filter circuit?low pass filter circuit?mixing circuit of the analog signal processing circuit.The digital circuit part includes analog-to-digital conversion circuit design and simulation,based on FPGA digital frequency meter module design and synthesis.Each function module of this system has been made the detailed introduction,design and simulation,and it has reached the design requirements of the system by the results.Finally,integrated design and simulation on the analog function modules of two kinds of sensing systems were done,and the analog circuit of the resonant mode integration circuit was designed with discrete device method,and the SAW gas sensor system analog circuit part of the integrated circuit principle diagram were obtained,which will give the stable foundation for self-excited SAW gas sensor integrated system.The SAW device has high sensitivity and good stability,and it's also easy for miniaturization and integration,and so it has been widely used in many kind of sensor systems with the developing application of internet technology.Surface acoustic wave sensors are being applied for a wide range of applications for its unique advantages,and so this research on the SAW gas sensor system function module integration is significant for the practical application of this kind of sensors.