激光测距系统整形模块和低通滤波模块优化设计
|
摘要
由于减小相位式激光测距系统的鉴相误差可提高测距精度,本文对鉴相器前置整形模块和后置滤波模块进行了优化设计,以提高鉴相精度。针对整形模块,引入了迟滞比较器,克服了传统开环比较电路在实际噪声条件下存在的多重触发缺陷,解决了鉴相器输出方波高电平宽度不稳定的问题。针对滤波模块,介绍了基于MC4044鉴相芯片的两种典型放大/滤波电路及其缺陷,使用FilterPro软件设计了4阶有源低通滤波器,并说明了它相对于典型设计的优势。实验结果表明:相比于开环比较器,本文设计的迟滞比较器避免了接地(GND)噪声引起的多重跳变现象,输出方波的上升沿时间由1.66μs下降为108ns;与基于MC4044的两种典型放大/滤波模块设计相比,本文设计的低通滤波电路克服了输出DC电平值非线性变化的缺陷线性度(R2)值由0.908 3提高至0.999 9)和灵敏度较低的缺陷(转化增益常量提高了96.5%),而输出DC电平上的干扰信号峰峰值则由50～230mV下降至10～20mV,有效减少了后级的A/D采样误差,提高了鉴相精度。
As the phase discrimination error of a phase laser ranging system effects its ranging accuracy,this paper optimizes the designs of a preceding stage(shaping circuit)and a subsequent stage(low-pass filter)in the phase detector.For the shaping circuit,a comparator with hysteresis was designed to avoid the multiple-triggered phenomenon caused by the noise on GND for open loop filters,and stabilizes the output of phase detector.For the low-pass filter,two typical amplifier/filter circuits based on MC4044 and their defects were introduced,a 4th-order low-pass filter was designed by using FilterPro,and its advantages were presented.Experimental results indicate that the multiple-triggered phenomenon is eliminated by using the hysteresis comparator designed,and the rise-time of output square wave falls to 108ns from 1.66μs as compared with that of a traditional opened-loop comparator.Furthermore,the 4th-order filter designed in this paper improves the linearity and sensitivity of the DC output,the linearity(R2)increases from 0.908 3 to 0.999 9,and the convention gain improves by 96.5%as compared with that of the typical designs of amplifier/filter circuits.Moreover,the peak-to-peak value of the interference signal on a Low Pass Filter(LPF)DC output decreases from 50-230mV to 10-20mV,which reduces the phase detection error effectively.
As the phase discrimination error of a phase laser ranging system effects its ranging accuracy,this paper optimizes the designs of a preceding stage(shaping circuit)and a subsequent stage(low-pass filter)in the phase detector.For the shaping circuit,a comparator with hysteresis was designed to avoid the multiple-triggered phenomenon caused by the noise on GND for open loop filters,and stabilizes the output of phase detector.For the low-pass filter,two typical amplifier/filter circuits based on MC4044 and their defects were introduced,a 4th-order low-pass filter was designed by using FilterPro,and its advantages were presented.Experimental results indicate that the multiple-triggered phenomenon is eliminated by using the hysteresis comparator designed,and the rise-time of output square wave falls to 108ns from 1.66μs as compared with that of a traditional opened-loop comparator.Furthermore,the 4th-order filter designed in this paper improves the linearity and sensitivity of the DC output,the linearity(R2)increases from 0.908 3 to 0.999 9,and the convention gain improves by 96.5%as compared with that of the typical designs of amplifier/filter circuits.Moreover,the peak-to-peak value of the interference signal on a Low Pass Filter(LPF)DC output decreases from 50-230mV to 10-20mV,which reduces the phase detection error effectively.
引文
[1]刘秉琦,周斌,武东生,等.双通道激光主动探测系统[J].光学精密工程,2012,20(2):241-246.LIU B Q,ZHOU B,WU D SH,et al..Dual-channel active laser detection system[J].Opt.Precision Eng.,2012,20(2):241-246.(in Chinese)
[2]张雏,周冰,沈学举,等.精确校正激光测距仪三光轴平行的理论计算方法研究[J].光学精密工程,2002,10(6):650-654.ZHANG CH,ZHOU B,SHEN X J,et al..Study of the calculation method for accurately adjusting laser range finder′s three optic axes to parallel to each other[J].Opt.Precision Eng.,2002,10(6):650-654.(in Chinese)
[3]贾方秀,丁振良,袁锋.相位法激光测距接收系统[J].光学精密工程,2009,17(10):2377-2384.JIA F X,DING ZH L,YUAN F.Phase-shift laser range finder receiver system[J].Opt.Precision Eng.,2009,17(10):2377-2384.(in Chinese)
[4]王选钢,缑宁祎,张珂殊.相位式激光测距谱分析鉴相的无偏改进[J].光学精密工程,2012,20(4):888-895.WANG X G,GOU N Y,ZHANG K SH.Unbiased improvement of spectrum analysis phase discrimination for phase-shift laser range finder[J].Opt.Precision Eng.,2012,20(4):888-895.(in Chinese)
[5]李烨,董秀珍,刘锐岗,等.生物磁感应成像中的高精度鉴相方法研究[J].北京生物医学工程,2006,25(4):351-354.LI Y,DONG X ZH,LIU R G,et al..The study of high resolution phase detecting method in biological magnetic induction imaging[J].Beijing Biomedical Engineering,2006,25(4):351-354.(in Chinese)
[6]胡宗恺,饶志宏.高精度数字鉴相技术的FPGA实现[J].通信技术,2010,12(43):177-179.LIU Z K,RAO ZH H.FPGA realization of high precise digital phase discrimination technology[J].Communications Technology,2010,12(43):177-179.(in Chinese)
[7]唐姗姗.用于地震检波的高精度A/D转换器设计[D].济南:山东大学,2010.TANG SH SH.Design of high-resolution A/D converter in seismometer[D].Jinan:Shandong University,2010.(in Chinese)
[8]刘黎辉,吴志海,汪道辉,等.高速迟滞比较电路研究及实验[J].电子测量技术,2007,30(2):46-49.LIU L H,WU ZH H,WANG D H,et al..Research and experiment of high-speed comparing circuit with hysteresis[J].Electronic Measurement Technology,2007,30(2):46-49.(in Chinese)
[9]尤政.光外差干涉相位检测技术[J].计量技术,1995,5:2-4.YOU ZH.Phase detection using heterodyne interference technology[J].Measurement Technology,1995,5:2-4.(in Chinese)
[10]刘振余,宋鸿霞,夏仲英.MC4044数字鉴相器的分析及应用[J].无线电通信技术,1982,4:20-29.LIU ZH Y,SONG H X,XIA ZH Y.Analysis and application of MC4044digital phase detector[J].Radio Communication Technology,1982,4:20-29.(in Chinese)
[11]SUN G F,GU Q T,LIU X B.Principle and implementation of an MC4044-based phase locked loop for constant speed control[J].Tsinghua Science and Technology,2000,5(4):409-413.
[12]赵洪志,赵洋,王佳,等.一种宽量程光外差干涉信号的处理方法[J].光学精密工程,1996,4(4):130 -133.ZHAO H ZH,ZHAO Y,WANG J,et al..A wide-range processing method for optical heterodyne interference signal[J].Opt.Precision Eng.,1996,4(4):130-133.(in Chinese)
[2]张雏,周冰,沈学举,等.精确校正激光测距仪三光轴平行的理论计算方法研究[J].光学精密工程,2002,10(6):650-654.ZHANG CH,ZHOU B,SHEN X J,et al..Study of the calculation method for accurately adjusting laser range finder′s three optic axes to parallel to each other[J].Opt.Precision Eng.,2002,10(6):650-654.(in Chinese)
[3]贾方秀,丁振良,袁锋.相位法激光测距接收系统[J].光学精密工程,2009,17(10):2377-2384.JIA F X,DING ZH L,YUAN F.Phase-shift laser range finder receiver system[J].Opt.Precision Eng.,2009,17(10):2377-2384.(in Chinese)
[4]王选钢,缑宁祎,张珂殊.相位式激光测距谱分析鉴相的无偏改进[J].光学精密工程,2012,20(4):888-895.WANG X G,GOU N Y,ZHANG K SH.Unbiased improvement of spectrum analysis phase discrimination for phase-shift laser range finder[J].Opt.Precision Eng.,2012,20(4):888-895.(in Chinese)
[5]李烨,董秀珍,刘锐岗,等.生物磁感应成像中的高精度鉴相方法研究[J].北京生物医学工程,2006,25(4):351-354.LI Y,DONG X ZH,LIU R G,et al..The study of high resolution phase detecting method in biological magnetic induction imaging[J].Beijing Biomedical Engineering,2006,25(4):351-354.(in Chinese)
[6]胡宗恺,饶志宏.高精度数字鉴相技术的FPGA实现[J].通信技术,2010,12(43):177-179.LIU Z K,RAO ZH H.FPGA realization of high precise digital phase discrimination technology[J].Communications Technology,2010,12(43):177-179.(in Chinese)
[7]唐姗姗.用于地震检波的高精度A/D转换器设计[D].济南:山东大学,2010.TANG SH SH.Design of high-resolution A/D converter in seismometer[D].Jinan:Shandong University,2010.(in Chinese)
[8]刘黎辉,吴志海,汪道辉,等.高速迟滞比较电路研究及实验[J].电子测量技术,2007,30(2):46-49.LIU L H,WU ZH H,WANG D H,et al..Research and experiment of high-speed comparing circuit with hysteresis[J].Electronic Measurement Technology,2007,30(2):46-49.(in Chinese)
[9]尤政.光外差干涉相位检测技术[J].计量技术,1995,5:2-4.YOU ZH.Phase detection using heterodyne interference technology[J].Measurement Technology,1995,5:2-4.(in Chinese)
[10]刘振余,宋鸿霞,夏仲英.MC4044数字鉴相器的分析及应用[J].无线电通信技术,1982,4:20-29.LIU ZH Y,SONG H X,XIA ZH Y.Analysis and application of MC4044digital phase detector[J].Radio Communication Technology,1982,4:20-29.(in Chinese)
[11]SUN G F,GU Q T,LIU X B.Principle and implementation of an MC4044-based phase locked loop for constant speed control[J].Tsinghua Science and Technology,2000,5(4):409-413.
[12]赵洪志,赵洋,王佳,等.一种宽量程光外差干涉信号的处理方法[J].光学精密工程,1996,4(4):130 -133.ZHAO H ZH,ZHAO Y,WANG J,et al..A wide-range processing method for optical heterodyne interference signal[J].Opt.Precision Eng.,1996,4(4):130-133.(in Chinese)
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心