Signal Detecting And Processing Circuit For FBAR Sensors Based On FPGA

As a mass sensor, film bulk acoustic wave resonator (FBAR) has been widely usedin biochemical detection for the characteristics such as label-free, high resolution, smallvolume. FBAR has high inherent frequency(0.5-20GHz). It is mostly used to analyzethe performance of FBAR with the bulky expensive network analyzer. But consideredits size and cost, it’s still difficult to make FBAR sensors get a wide application. Soresearch on a signal detection and processing circuit for the FBAR sensor independentof network analyzer have great significance to expand its scope of application.This paper carries out research on a GHz band signal detection and processingcircuit according to the requirement of FBAR sensors. The paper completes the logicdesign with FPGA as the core device and the hardware design of the signal detectionand processing circuit based on platform of Quartus II and Altium Designer6.0. Themain work of this paper including:①Based on the analysis of structure and working principle of FBAR sensors, thesignal of the sensors has charateristic of high frequency, and according to the structureof network analyzer, the overall design of the FBAR sensor signal detection andprocessing circuit based on FPGA is put forward;②According to theoretical calculation, simulation and optimization for the keymodules, the design of the FBAR sensor signal detection and processing circuit iscompleted. And the PCB design of the circuit is completed in accordance with the EMCtheory;③According to the output signal characteristic of the FBAR sensor signaldetection and processing circuit, the signal acquisition system is completed based on theFPGA, it communicated with PC by USB interface. And its feasibility is verified by thefunction simulation;④Set up the experiment platform and realize the test of duplexer. The resonantfrequency of duplexer transmitter is1.81GHz, which is consistent with the result by thenetwork analyzer measured. And the relative error is1.1%.