FPGA硅微谐振式加速度计测频电路设计+电路图+程序
毕业论文关键词 频率测量 锁相环 FPGA MATLAB
Title The Frequency Measurement Circuit of Micromechanical Silicon Resonant Accelerometer
Abstract The micromechanical silicon resonant accelerometer can transform the measured acceleration into frequency shift which is stable and reliable，so the accelerometer may get better performance．Of course, this also simplifies processing circuit of the application system . This will take the full advantages of small size for MEMS sensors. So to make a frequency measurement circuit of high precision and high reliability is crucial. So the paper discussed the design of the data acquisition system for the micromechanical silicon resonant accelerometer．The design target is that the system can acquire the differential frequency signals of the resonant accelerometer with the resolution of 0.01 Hz, corresponding to 0.125mg on condition that the resonant accelerometer has a normal frequency of 23 KHz, a scale factor of 80 Hz/g，and a measuring range of±15g. In this paper ,new frequency measurement method based on PLL(Phase-locked loop) is adopted. Phase-locked loop consists of phase discriminator, loop filter and the voltage-controlled oscillator of three parts. Divide the functions of different modules first, and then find the theory and method to implement it, finally, various modules patchwork into frequency measuring circuit. In this design, to determine the design scheme, use MATLAB to do the simulation, finally on the FPGA using Verilog HDL language programming to achieve the function of frequency measurement. At the end of the experiment, the frequency measurement circuit completely meet the requirements, and resolution is 0.08 mHz, so this kind of frequency measurement method can be applied to the micromechanical silicon resonant accelerometer.
Keywords Frequency Measurement Phase-Locked Loop MATLAB FPGA
目 次
1．绪论. 1
1.1 微机电系统与硅微加速度计简介 1
1.1.1微机电系统概述 1
1.1.2硅微加速度计概述 . 2
1.1.3硅微谐振式加速度计工作原理 2
1.3 论文的主要内容.. 4
2．硅微谐振式加速度计数据采集方案.. 5
2.1频率测量的基本方法 . 5