The method to generate 8 pulse - width modulation waves with microprocessor software by mechanism of timesharing is proposed 提出了基于分時機制的8路pwm波軟件生成法。
This paper starts the research of the liquid floated pendulous accelerometer testing system according to the engineering . at first , this paper gives the brief introduction of the history and present status of accelerometer and its testing technology , the working principium and math model of the liquid floated pendu - lous accelerometer , and then , decides the binary width pulse force retrim loop as the design proposal of testing system , researches the transfer function of every part in the system emphasizly , analyses the stability of the whole accelerometer testing system from the angle of control theoretics by the open loop transfer function of system , and designed the correcting net , analyses the basal problems such as resolution , sampling restraint , precision and so on , designs the hardware testing circuits such as preamplification , band - pass filter , alternating amplifier , phase sensitive demodulatorn , pulse - width modulation , frequency scale circuit , moment current generator . finally , using the graphics program language labv - iew which is designed for testing field especially by ni accomplishes the solfware design of testing system , realized the testing functions 首先對加速度計及其測試技術的發展歷史和現狀,液浮擺式加速度計的工作原理和數學模型等作了簡要的介紹,然后確定了以二元調寬脈沖再平衡測試回路為設計方案,并從控制理論的角度進行了分析,著重研究了系統中各部分的傳遞函數,利用系統開環傳遞函數分析了系統的穩定性,同時設計了系統的校正網絡;分析了二元調寬脈沖再平衡測試回路的分辨率、采樣約束以及測試精度等基本問題,并按照系統分析的結果設計了包括前置放大、帶通濾波、交流放大、相敏解調、脈寬調制、頻標電路以及力矩電流發生器等測試系統各部分硬件電路,驗證了電路的正確性,最后按照測試系統的要求,采用了美國ni公司專為測試領域所開發的虛擬儀器工具? ? labview作為測試軟件開發工具,利用該圖形化編程語言完成了測試系統軟件部分的設計,實現了測試功能。
Two kinds method of design binary subwavelength diffractive microlenses are illustrated with emphasis . i obtained the result that the method of subwavelength pulse - width modulation is better than the method of linear approximation for continuous phase piece in designing binary subwavelength diffractive microlenses by comparing them 重點說明了二臺階亞波長衍射微透鏡的兩種設計方法,并對兩種方法作了比較,得出了亞波長結構的脈沖寬度調制法優于連續位相的線性進似法的結論。