光电工程
光電工程
광전공정
OPTO-ELECTRONIC ENGINEERING
2010年
4期
53-59
,共7页
脉冲激光测距%时间数字转换%延迟线插入法%FPGA
脈遲激光測距%時間數字轉換%延遲線插入法%FPGA
맥충격광측거%시간수자전환%연지선삽입법%FPGA
pulsed laser ranging%time-to-digital conversion%interpolation method of delay-line%FPGA
为了提高系统的集成度,同时兼顾精度,介绍用FPGA延迟线插入法采实现较高精度的脉冲激光测时、测距的原理和技术途径.FPGA延迟线插入法是在直接计数法的基础上,采用FPGA内部延时单元将时间间隔转化为数字量,经高速锁存器锁存后得到代表延时信息的温度计编码值来实现高分辨率的时间测量.提出了一种实用的高速时钟下(400 MHz)延迟线延时信息的锁存方法,并设计了FPGA时间数字转换电路及其延迟单元时间测量电路.测试结果表明,FPGA延迟线插入法可以将单点时间分辨率提高到80 ps,多次测量可达40 ps,对应距离分辨率为毫米级.将其应用于脉冲激光测距系统,进行了测距实验研究,给出了实验数据和测量误差分析,最终得到±10 cm的测距精度.
為瞭提高繫統的集成度,同時兼顧精度,介紹用FPGA延遲線插入法採實現較高精度的脈遲激光測時、測距的原理和技術途徑.FPGA延遲線插入法是在直接計數法的基礎上,採用FPGA內部延時單元將時間間隔轉化為數字量,經高速鎖存器鎖存後得到代錶延時信息的溫度計編碼值來實現高分辨率的時間測量.提齣瞭一種實用的高速時鐘下(400 MHz)延遲線延時信息的鎖存方法,併設計瞭FPGA時間數字轉換電路及其延遲單元時間測量電路.測試結果錶明,FPGA延遲線插入法可以將單點時間分辨率提高到80 ps,多次測量可達40 ps,對應距離分辨率為毫米級.將其應用于脈遲激光測距繫統,進行瞭測距實驗研究,給齣瞭實驗數據和測量誤差分析,最終得到±10 cm的測距精度.
위료제고계통적집성도,동시겸고정도,개소용FPGA연지선삽입법채실현교고정도적맥충격광측시、측거적원리화기술도경.FPGA연지선삽입법시재직접계수법적기출상,채용FPGA내부연시단원장시간간격전화위수자량,경고속쇄존기쇄존후득도대표연시신식적온도계편마치래실현고분변솔적시간측량.제출료일충실용적고속시종하(400 MHz)연지선연시신식적쇄존방법,병설계료FPGA시간수자전환전로급기연지단원시간측량전로.측시결과표명,FPGA연지선삽입법가이장단점시간분변솔제고도80 ps,다차측량가체40 ps,대응거리분변솔위호미급.장기응용우맥충격광측거계통,진행료측거실험연구,급출료실험수거화측량오차분석,최종득도±10 cm적측거정도.
In order to improve the system density of integration and maintain the precision simultaneously, Field Programmable Gate Array (FPGA) delay-line interpolator is introduced to realize pulsed laser ranging with high time resolution and precision. The method is based on clock circle dived principle. The time errors in direct digital counting method are converted to digital flash-code by latching the output of FPGA delay cells. Then a latch method for latching the delay cell signals was proposed based on the high frequency clock (400 MHz). The corresponding time-to-digital interpolation converter and delay cell time measurement were also designed. The measurement shows that single-shot resolution can be improved to 80ps, and average resolution can reach 40ps (ram level). Applied in pulsed laser range finder, the distance results are given and the error of FPGA interpolation method is analyzed in theory. Finally, the precision of ± 10 centimeter level is achieved.
