An Fpga-based System for the Measurement of Frequency Noise and Resolution of Qcm Sensors

−− The use of Quartz Crystal Oscillators (QCM) as high accuracy microbalance sensors is limited by the frequency noise present in the circuit. This work deals with the design and implementation of an FPGA-based system for the real-time measurement of the frequency noise and resolution of QCM sensors. This reconfigurable system integrates the frequency measurement and the mass resolution computation in a single FPGA chip. Parallel processing, pipeline stages and prediction techniques are combined in order to accelerate the computations maintaining a low hardware complexity. By this way, a reconfigurable and low cost QCM sensor system working as a standalone measurement platform with communication capabilities is obtained. The implemented system was validated with a Xilinx Virtex-4 FPGA and a QCM sensor operating in damping media for electrochemical applications. Keywords−−FPGA, QCM, SoC, DSP, Frequency Noise, Mass Resolution, Allan Deviation.