(四川大學測試技術(shù)與控制工程系,四川 成都 610065)
摘 要:高頻相位測量裝置是激光輪廓測量儀不可缺少的一部分,它完成的工作是對兩路被測信號進行相位測量。文中介紹了一種用混頻原理和鎖相環(huán)技術(shù)將高頻轉(zhuǎn)化為低頻,并且用相關(guān)計數(shù)法對低頻相位進行測量的方法。低頻部分主要是利用了單片機豐富的軟硬件資源和CPLD器件靈活多用功能來實現(xiàn)的。通過混頻電路和低頻相位測量電路的組合,能較高精度地完成此相位測量任務(wù)。
關(guān)鍵詞:混頻原理;鎖相環(huán)技術(shù);單片機;CPLD;相關(guān)計數(shù)
中圖分類號:TM933.3+12, TN249 文獻標識碼:A
文章編號:1672-4984(2008)01-0022-03
Measuring circuit design for high-frequency phase of laser profilometer
OU Wen-chu, XIE Chi
(Department of Testing Technology and Control Engineering,Sichuan University,Chengdu 610065,China)
Abstract: High-frequency phase measuring equipment is an indispensable part of the laser profilometer. Its work is to measure the phases of two measured signals. One measurement method using designed circuit to change high-frequency into low-frequency with the frequency mixing theory and phase locking technique, then using correlative counting method to measure low-frequency was introduced. The low-frequency part mainly used the ample resource of SCM and flexible functions of CPLD. With combination of frequency mixing circuit and low-frequency measurement circuit, the designed circuit can measure the phase more accurately.
Key words: Frequency mixing theory; Phase locking technique; SCM(single-chip computer); CPLD; Correlative counting method
Editor:liyan