基于CPLD的高速光纤光栅解调仪研究
摘要
光纤Bragg光栅传感器对待测量采用波长编码,对光强的波动及光的偏振态不敏感,抗干扰能力强,测量方便,因此光纤光栅在传感方面的应用得到了国内外的广泛关注。目前已推出商用光纤光栅解调产品,但主要以有源解调方法为主,采样速度在几赫兹到几百赫兹左右,仅能满足静态或准静态测量的需要,不能满足振动、地质监测等动态环境所要求的高速采样。为了进一步满足动态测量的要求,需提高光纤光栅解调仪的采样和传输速度。本课题针对这一要求,设计了基于CPLD总线控制和边缘滤波器的高速光纤Bragg光栅解调仪。完成了解调仪的光路及电路设计,实现了光纤光栅解调系统的解调数据的高速传输及在计算机平台上的处理、显示和存储。
本论文的主要工作如下:
1、基于粗波分复用器(CWDM)设计了光路解调部分,利用可调谐激光器对CWDM进行测试,测得其可用工作区间为1535.4nm-1542nm,响应灵敏度可达15dB/nm,保证了解调系统的快响应速度和高分辨率。
2、以CPLD作为时序主控芯片,研制了控制总线传输的高速光栅解调仪的数据采集与USB传输硬件,包括AD采样以及USB接口控制部分。
3、使用Verilog语言设计完成了CPLD的主控程序,利用模块式编程方式完成了对同步传输对系统时钟的设计要求,实现了对整个解调电路及接口传输的时序控制,保障了数据的高速无重复传输。
4、完成了EZ-USB2.0接口芯片的固件驱动程序设计,经过对比研究,设计了同步批量半满传输的固件程序,通过对USB芯片的传输模式及控制命令的设计,实现了USB接口高速无重复传输数据。
5、建立实验系统,对解调系统的采样速度、传输性能、解调范围和波长分辨率进行了实验分析与研究。实验结果表明该解调系统的采样速度为240KHz,可解调20KHz以下的动态信号;深入研究了三种典型的光输入功率下对解调范围的影响,光功率大于或等于-14dbm时,解调范围为1535.4nm-1542nm;分辨率达到了18pm。
The measurement signal of Fiber Bragg Grating Sensors is wavelength encoded, is not sensitive to the intensity and the state of polarization,and has powerful anti-disturbing capability, that is why the application of the fiber Bragg grating in sensor field has been widespread concern at home and abroad. There are some demodulation products for fiber grating sensors, which are mostly based on passive demodulation technologies, and the samling rate is between several hertz to several hundred hertz or so, can only meet the needs of static or quasi-static measurement, but is not enough to achieve the geological monitoring in dynamic environment. In order to adapt the requirement of dynamic measurement, increasing the sampling and transmission speed of the fiber grating demodulation is needed. As a result, the design of the High Speed Fiber Bragg Grating Demodulation based on CPLD and the Thin Flim Filter technologies is proposed in this papper. The design of optical path and circuit board is completed in this papper; achieve the high-speed transmission of fiber grating demodulation, the date processing, display and store on computer.
1、The demodulation for wavelength code in optical path is designed based on Coarse Wavelength Division Multiplexing (CWDW). The performance test on CWDM is done, the experiment result shows that the effective interval is from 1535.4nm to 1542nm, and the sensitivity is arrived at 15dB/nm, which makes the response speed and wavelength differentiating rate high.
2、The Complex Programmable Logic Devic (CPLD) is used as the main chip in the design of the acquisition and data transmission hardware system for the high speed FBG demodulation, including the hardware circuit of the A/D chip and the interface control circuit of USB in the project.
3、The main control procedure is completed based on Verilog, and the clock of synchronous transmission is finished by Module Programming, which achieves the timing control for the demodulation circuit and the interface, and keeps the data transmitted with non-repetitive on high-speed.
4、The firmware program of USB interface chip CY7C68013 is designed; the design of half-full bulk transmission for firmware programming is done by contrast. The data is transmitted with non-repetitive on high-speed through the control command design on the USB chip.
5、The experiment system is build, to analyze and research sampling rate, transmission performance, wavelength range and resolution of the demodulation. The experiment results show that the samling rate is 240 KHz, and dynamic signals on 20 KHz can be de-emphasised well. What is more, the impact of demodulation under three typical input opt-power is researched, the demodulation range is from 1535.4nm~1542nm, the resolution is 18pm when the input power is greater than -14dBm.
本论文的主要工作如下:
1、基于粗波分复用器(CWDM)设计了光路解调部分,利用可调谐激光器对CWDM进行测试,测得其可用工作区间为1535.4nm-1542nm,响应灵敏度可达15dB/nm,保证了解调系统的快响应速度和高分辨率。
2、以CPLD作为时序主控芯片,研制了控制总线传输的高速光栅解调仪的数据采集与USB传输硬件,包括AD采样以及USB接口控制部分。
3、使用Verilog语言设计完成了CPLD的主控程序,利用模块式编程方式完成了对同步传输对系统时钟的设计要求,实现了对整个解调电路及接口传输的时序控制,保障了数据的高速无重复传输。
4、完成了EZ-USB2.0接口芯片的固件驱动程序设计,经过对比研究,设计了同步批量半满传输的固件程序,通过对USB芯片的传输模式及控制命令的设计,实现了USB接口高速无重复传输数据。
5、建立实验系统,对解调系统的采样速度、传输性能、解调范围和波长分辨率进行了实验分析与研究。实验结果表明该解调系统的采样速度为240KHz,可解调20KHz以下的动态信号;深入研究了三种典型的光输入功率下对解调范围的影响,光功率大于或等于-14dbm时,解调范围为1535.4nm-1542nm;分辨率达到了18pm。
The measurement signal of Fiber Bragg Grating Sensors is wavelength encoded, is not sensitive to the intensity and the state of polarization,and has powerful anti-disturbing capability, that is why the application of the fiber Bragg grating in sensor field has been widespread concern at home and abroad. There are some demodulation products for fiber grating sensors, which are mostly based on passive demodulation technologies, and the samling rate is between several hertz to several hundred hertz or so, can only meet the needs of static or quasi-static measurement, but is not enough to achieve the geological monitoring in dynamic environment. In order to adapt the requirement of dynamic measurement, increasing the sampling and transmission speed of the fiber grating demodulation is needed. As a result, the design of the High Speed Fiber Bragg Grating Demodulation based on CPLD and the Thin Flim Filter technologies is proposed in this papper. The design of optical path and circuit board is completed in this papper; achieve the high-speed transmission of fiber grating demodulation, the date processing, display and store on computer.
1、The demodulation for wavelength code in optical path is designed based on Coarse Wavelength Division Multiplexing (CWDW). The performance test on CWDM is done, the experiment result shows that the effective interval is from 1535.4nm to 1542nm, and the sensitivity is arrived at 15dB/nm, which makes the response speed and wavelength differentiating rate high.
2、The Complex Programmable Logic Devic (CPLD) is used as the main chip in the design of the acquisition and data transmission hardware system for the high speed FBG demodulation, including the hardware circuit of the A/D chip and the interface control circuit of USB in the project.
3、The main control procedure is completed based on Verilog, and the clock of synchronous transmission is finished by Module Programming, which achieves the timing control for the demodulation circuit and the interface, and keeps the data transmitted with non-repetitive on high-speed.
4、The firmware program of USB interface chip CY7C68013 is designed; the design of half-full bulk transmission for firmware programming is done by contrast. The data is transmitted with non-repetitive on high-speed through the control command design on the USB chip.
5、The experiment system is build, to analyze and research sampling rate, transmission performance, wavelength range and resolution of the demodulation. The experiment results show that the samling rate is 240 KHz, and dynamic signals on 20 KHz can be de-emphasised well. What is more, the impact of demodulation under three typical input opt-power is researched, the demodulation range is from 1535.4nm~1542nm, the resolution is 18pm when the input power is greater than -14dBm.
引文
[1] Kersey A D, Davis M D, Patrick HJ, et al. Fiber grating sensor[J] .IEEE Journal of Lightwave Technology ,1997 ,15 :144221463.
[2] Rao YJ In-fibre Bragg grating sensor[J] Measurement Science Technology ,1997 ,8 :3552375.
[3] Varnham M P,Barlow A J,Payne D N,et al. Polarimetric Strain Gauges Using High Birefringence Fibers. Electronics Letters,1983,19(17):699-700.
[4] Corke M,Kersey A D,Liu K,et al.Remote Temperature Sensing Using Polarization Preserving Fiber.Electronics Letters,1984,20(2):699-700.
[5] Dakin J P,Pratt D J,Bibby G W,et al. Distributed optical fiber Raman temperature sensor using a semiconductor light source and detector. Electron.Lett,1995, 21:569-570.
[6] Meltz G,Morey W W,Glenn W H,et al. In-fiber Bragg-grating temperature and strain sensors. Proceedings of the ISAAerospace Instrumentation Symposium,1988,34,239-242.
[7] Lee C E,Taylor H F. Interferometric optical fiber sensors using internal mirrors. Electronics Letters,1988,24(4):193-194.
[8] Valis T,Hogg D,Measures R M. Localized fiber optic sensors embedded in composite materials.SPIE 1170,1989,495-504.
[9] Valis T, Hogg D,Measures R M. Fiber-optic Fabry-Perot strain rosettes.Smart Materials and Structures,1992,1(3):227-228.
[10] Murphy KA,Gunther M F,Vengsarkar A M,Claus R O. Fabry-Perot fiber optic sensors in full-scale fatigue testing on an F-15 Aircraft. SPIE 1518, Fiber Optic Smart Structures and SkinsⅣ,134-144.
[11]王剑,基于单片机的光纤光栅解调仪的研制:[硕士学位论文],武汉:武汉理工大学,2006-05-01
[12] Kersey A D,Berkoff T A,Morey W W. High resolution fibre grating based strain sensor with interferometric wavelength shift detection[J] . Electron Lett ,1992. 23 :2362238.
[13] Flavin D A,McBride R,Jones J DC. Short optical path scan interferometric interrogation of a fibre Bragg grating embedded in a composite.Electron.Lett.,1997,33(4):319-321.
[14] Melle S M, Alavie A T, Karr S, et al. A Bragg grating-tuned fiber laser strain sensor system. IEEE Photonics Technology Letters, 1993, 5 (2):263– 266
[15] Geiger H,Xu M G,Dakin J P. Multiplexed measurements of strain using short and long gauge length sensors. SPIE 1995,2507:25-34.
[16] Davis M A,Kersey A D. All fiber Bragg grating strain-sensor demodulation technique using a wavelength division coupler. Electron.Lett, 1994, 30(1): 75-77.
[17] Chung S ,KimJ ,Bong Ahn Yu , et al.Afiber Bragg grating sensor demodulation technique using a polarization maintaining fiber loop mirror[J ] . IEEE Photonics Technol Lett ,2001 ,13(12) :134321345.
[18]宣海燕,基于USB总线的高速光纤Bragg光栅解调系统的研究:[硕士学位论文],天津:天津大学,2007-06
[19]王云新,便携式大量程光纤Bragg光栅解调系统的研究:[硕士学位论文],天津:天津大学,2006-01
[20]王颖,姚跃飞.基于CPLD扩展的嵌入式织机控制系统硬件结构设计[J].浙江理工大学学报, 2007,(02)
[21]谭月杰,在CPLD中实现高速异步串行通信[J]电子技术, 2005,(09) .
[22]王道宪. CPLD/FPGA可编程逻辑器件应用与开发,北京:国防工业出版社,2004,01,P60-68
[23] (美)Charles E.Spurgeon著,以太网技术入门与实现(张健袁晓辉苗沛荣等译),北京:机械工业出版社,1998
[24]陈婷婷,USB技术研究:[硕士学位论文],北京:北京交通大学,2006
[25]孙雪燕秦芳齐传兵,基于USB2.0的高速数据采集系统设计,高性能计算技术,2005(174):43~46
[26]王剑,基于单片机的光纤光栅解调仪的研制:[硕士学位论文],武汉:武汉理工大学,2006-05-01
[27]靳伟廖延彪张志鹏,导波光学传感器:原理与技术[M],北京:科学出版社,1998
[28]廖延彪,光纤光学,北京:清华大学出版社,2000年3月
[29]孙雨南王茜蒨,光纤技术理论基础与应用,北京:北京理工大学出版社,2006
[30] Melle S M,Liu K,Measures R M.Practical fiber optic Bragg grating strain gauge system,Applied Optics,1993,32(19):3601~3609
[31] Byron K C,sugden K,Bricheno T,et al. Fabrication of chirped bragg gratings in photosensitive fibre. Electronics Letters,1993,29(18):1658-1660.
[32] Davis M A,Kersey A D.All fiber Bragg grating strain-sensor demodulation technique using a wavelength division coupler.Electron.Lett,1994,30(1):75～77
[33]丁龙刚马虹,DWDM技术进展及光复用器,电力系统通信,2004(10):40~43
[34]林学煌编著,光无源器件,北京:人民邮电出版社,1998
[35]宣海燕,基于USB总线的高速光纤Bragg光栅解调系统的研究:[硕士学位论文],天津:天津大学,2007-06
[36]徐宁赵洪张剑张朝起,利用波分复用器实现FBG动态传感解调,哈尔滨理工大学学报,2006,11(2):127~134
[37]孙志平,USB2.0规范及EZ-USB FX2外设控制,计算机科学与技术,2004(5):56~60
[38]孙志平,USB2.0规范及EZ-USB FX2外设控制,计算机科学与技术,2004(5):56~60
[39]张国强,基于USB规范的交互式数据采集系统的设计与实现:[硕士学位论文],西南石油大学,2003
[40] Analog Devices,AD8304 Data Sheet,2002
[41]鲍黎波,艾勇左韬胡晟,无线激光通信系统USB接口的设计与调试,红外与激光工程,2004,33(5):473~476
[42]周立功,夏宇闻,单片机与CPLD综合应用技术,北京:北京航空航天大学出版社,2003,08,P94-99
[43] Maxim,MAX882 Data Sheet,1995
[44]周云峰孙书鹰王宏,基于USB2.0的高速同步数据采集系统设计,电子技术应用,2004(2):16~18
[45]钱峰,EZ-USB FX2单片机原理、编程及应用,北京:北京航空航天大学出版社,2006.3
[46]粱鸿翔王润田,基于USB2.0的同步高速数据采集器的设计,电子技术应用,2004(8):13~15
[47]张弘,USB接口设计,西安:西安电子科技大学出版社,2002
[48]万静,李忠民,USB2.0通用串行总线软件系统的设计,电子工程师,2004(5):55~58
[49]粱鸿翔王润田,基于USB2.0的同步高速数据采集器的设计,电子技术应用,2004(8):13~15
[50]万静李忠民,USB2.0通用串行总线软件系统的设计,电子工程师,2004(5):55~58
[51]武安河邰铭于洪涛,Windows 2000/XP WDM设备驱动程序开发,北京:电子工业出版社,2003
[52] Rizkalla S H,Mufti A A,Tadros G. Recent innovation for concrete highway bridges in Canada.Anaheim,CA,USA.International SAMPE Symposium and Exhibition, 1997, 42(1):281-287
[2] Rao YJ In-fibre Bragg grating sensor[J] Measurement Science Technology ,1997 ,8 :3552375.
[3] Varnham M P,Barlow A J,Payne D N,et al. Polarimetric Strain Gauges Using High Birefringence Fibers. Electronics Letters,1983,19(17):699-700.
[4] Corke M,Kersey A D,Liu K,et al.Remote Temperature Sensing Using Polarization Preserving Fiber.Electronics Letters,1984,20(2):699-700.
[5] Dakin J P,Pratt D J,Bibby G W,et al. Distributed optical fiber Raman temperature sensor using a semiconductor light source and detector. Electron.Lett,1995, 21:569-570.
[6] Meltz G,Morey W W,Glenn W H,et al. In-fiber Bragg-grating temperature and strain sensors. Proceedings of the ISAAerospace Instrumentation Symposium,1988,34,239-242.
[7] Lee C E,Taylor H F. Interferometric optical fiber sensors using internal mirrors. Electronics Letters,1988,24(4):193-194.
[8] Valis T,Hogg D,Measures R M. Localized fiber optic sensors embedded in composite materials.SPIE 1170,1989,495-504.
[9] Valis T, Hogg D,Measures R M. Fiber-optic Fabry-Perot strain rosettes.Smart Materials and Structures,1992,1(3):227-228.
[10] Murphy KA,Gunther M F,Vengsarkar A M,Claus R O. Fabry-Perot fiber optic sensors in full-scale fatigue testing on an F-15 Aircraft. SPIE 1518, Fiber Optic Smart Structures and SkinsⅣ,134-144.
[11]王剑,基于单片机的光纤光栅解调仪的研制:[硕士学位论文],武汉:武汉理工大学,2006-05-01
[12] Kersey A D,Berkoff T A,Morey W W. High resolution fibre grating based strain sensor with interferometric wavelength shift detection[J] . Electron Lett ,1992. 23 :2362238.
[13] Flavin D A,McBride R,Jones J DC. Short optical path scan interferometric interrogation of a fibre Bragg grating embedded in a composite.Electron.Lett.,1997,33(4):319-321.
[14] Melle S M, Alavie A T, Karr S, et al. A Bragg grating-tuned fiber laser strain sensor system. IEEE Photonics Technology Letters, 1993, 5 (2):263– 266
[15] Geiger H,Xu M G,Dakin J P. Multiplexed measurements of strain using short and long gauge length sensors. SPIE 1995,2507:25-34.
[16] Davis M A,Kersey A D. All fiber Bragg grating strain-sensor demodulation technique using a wavelength division coupler. Electron.Lett, 1994, 30(1): 75-77.
[17] Chung S ,KimJ ,Bong Ahn Yu , et al.Afiber Bragg grating sensor demodulation technique using a polarization maintaining fiber loop mirror[J ] . IEEE Photonics Technol Lett ,2001 ,13(12) :134321345.
[18]宣海燕,基于USB总线的高速光纤Bragg光栅解调系统的研究:[硕士学位论文],天津:天津大学,2007-06
[19]王云新,便携式大量程光纤Bragg光栅解调系统的研究:[硕士学位论文],天津:天津大学,2006-01
[20]王颖,姚跃飞.基于CPLD扩展的嵌入式织机控制系统硬件结构设计[J].浙江理工大学学报, 2007,(02)
[21]谭月杰,在CPLD中实现高速异步串行通信[J]电子技术, 2005,(09) .
[22]王道宪. CPLD/FPGA可编程逻辑器件应用与开发,北京:国防工业出版社,2004,01,P60-68
[23] (美)Charles E.Spurgeon著,以太网技术入门与实现(张健袁晓辉苗沛荣等译),北京:机械工业出版社,1998
[24]陈婷婷,USB技术研究:[硕士学位论文],北京:北京交通大学,2006
[25]孙雪燕秦芳齐传兵,基于USB2.0的高速数据采集系统设计,高性能计算技术,2005(174):43~46
[26]王剑,基于单片机的光纤光栅解调仪的研制:[硕士学位论文],武汉:武汉理工大学,2006-05-01
[27]靳伟廖延彪张志鹏,导波光学传感器:原理与技术[M],北京:科学出版社,1998
[28]廖延彪,光纤光学,北京:清华大学出版社,2000年3月
[29]孙雨南王茜蒨,光纤技术理论基础与应用,北京:北京理工大学出版社,2006
[30] Melle S M,Liu K,Measures R M.Practical fiber optic Bragg grating strain gauge system,Applied Optics,1993,32(19):3601~3609
[31] Byron K C,sugden K,Bricheno T,et al. Fabrication of chirped bragg gratings in photosensitive fibre. Electronics Letters,1993,29(18):1658-1660.
[32] Davis M A,Kersey A D.All fiber Bragg grating strain-sensor demodulation technique using a wavelength division coupler.Electron.Lett,1994,30(1):75～77
[33]丁龙刚马虹,DWDM技术进展及光复用器,电力系统通信,2004(10):40~43
[34]林学煌编著,光无源器件,北京:人民邮电出版社,1998
[35]宣海燕,基于USB总线的高速光纤Bragg光栅解调系统的研究:[硕士学位论文],天津:天津大学,2007-06
[36]徐宁赵洪张剑张朝起,利用波分复用器实现FBG动态传感解调,哈尔滨理工大学学报,2006,11(2):127~134
[37]孙志平,USB2.0规范及EZ-USB FX2外设控制,计算机科学与技术,2004(5):56~60
[38]孙志平,USB2.0规范及EZ-USB FX2外设控制,计算机科学与技术,2004(5):56~60
[39]张国强,基于USB规范的交互式数据采集系统的设计与实现:[硕士学位论文],西南石油大学,2003
[40] Analog Devices,AD8304 Data Sheet,2002
[41]鲍黎波,艾勇左韬胡晟,无线激光通信系统USB接口的设计与调试,红外与激光工程,2004,33(5):473~476
[42]周立功,夏宇闻,单片机与CPLD综合应用技术,北京:北京航空航天大学出版社,2003,08,P94-99
[43] Maxim,MAX882 Data Sheet,1995
[44]周云峰孙书鹰王宏,基于USB2.0的高速同步数据采集系统设计,电子技术应用,2004(2):16~18
[45]钱峰,EZ-USB FX2单片机原理、编程及应用,北京:北京航空航天大学出版社,2006.3
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