The Research Of Signal Acquisition And Processing For A Digital Micromirror Spectrometer Based On ARM

In this thesis, the signal acquisition and processing system based on ARM isstudied, which is the key technology of the digital micromirror spectrometer prototypeprevious builded in our laboratory, which is for food safety monitoring. The embeddeddesign scheme of the spectrometer puts the functions such as detection, acquisition,display, analysis all in one and the overall system is fixed, which allows monitoringfood safety on-line and out laboratory. That’s useful to solve food safety problems andpromote the development of food safety monitoring. The main research works are asfollows:①Analyze the current situation of signal acquisition system and informationprocessing method of the digital micromirror spectrometer at home and abroad,andsummarize the main problems of various solutions. Then combine with the digitalmicromirror spectrometer prototype of our laboratory to determine the main researchcontents of this thesis;②Analyze several popular processors, operating systems and developmentenvironments, and select the proper scheme of the digital micromirror spectrometerprototype of our laboratory. Determine the overall design scheme of signal acquisitionand processing based on ARM;③Determine the signal acquisition program of the digital micromirrorspectrometer based on ARM; Study the ADC conversion principle and then determinethe parameters in order to meet the requirements of the OK6410development board andthe spectrometer; Meanwhile, design ADC bottom drive, interrupt control andconditioning circuit;④A complementary S matrix encoding algorithm is proposed to improve thetraditional Hadamard transform signal processing algorithm. Through modeling analysis,the improvements of noise and energy based on the complementary S matrix is studied;⑤Design the software for the digital micromirror spectrometer;Develope the filesbasic operation module,coordinate of graphic display module, spectral preprocessingmodule, Hadamard transform module, spectral calibration modules and so on.Throughtesting software, all of the modules can meet the design requirements;⑥Set up the experimental platform，and test the signal conditioning circuit andOK6410development board acquisition module. The result shows that achieve the phase-locked chopper function and synchronous trigger signal acquisition function, andthe sampling rate is478SPS, which meets the design requirements. The experimentsprove that the SNR can be increased about2.05times than S-template and energy canbe increased about2times;...