The Data Acquisition and Analysis System of Grating Geophone Based on FPGA

The data acquisition system before is usually based on single chip, whose working frequency is low so that the data sampled is easy missing. And the data analysis system normal is based on electronic subdivision circuit, which is complex and unsteady. To improve the measuring precision and resolution of grating geophone, a data acquisition and analysis system based on FPGA is designed. The data acquisition unit, asynchronous FIFO memory which is used for storing moiré fringe signal sampled, data analysis unit and so on contained in this system are designed based on hardware description language Verilog. And two software analysis principles are introduced in this system. Amplitude-periods combined principle is used for picking out the shift point accurately and then the software subdivision principle is used for getting the exact information at the shift point in data analysis unit. In this way, the size of circuit board is reduced effectively and high speed acquisition system and high precision grating geophone can be realized.