基于FFT频谱分析算法的虚拟示波器的研制
|
摘要
测试技术几乎涉及所有的工程技术领域,测试技术已经成为生产效率和制造能力的重要标志。多年来,为了提高生产效率和产品性能,各国大力发展自动测试系统及其相关技术。而我国对自动测试系统的研究较晚,尚不成熟,大部分精密测试设备都依靠进口且价格昂贵。如今虚拟仪器技术的出现,又给了我们新的发展契机。
本文融合DSP技术和虚拟仪器技术,构建了测试信号处理分析系统,研制完成直升机自动测试系统中的虚拟示波器模块。不同于当前主流虚拟示波器结构“数据采集卡+上位机数据处理系统”,本文利用下位机DSP模块完成了数据采集功能和数据处理功能,避免了海量数据传输的问题,提高了系统实时性。上位机模块负责调度自动测试系统的各个模块的测试程序集。
本文重点研究数字信号处理分析的相关理论及其在DSP模块上的实现。在数字滤波方面,应用MATLAB工具对Kaiser窗FIR低通滤波器进行了参数优化和仿真验证,使窗函数旁瓣引起的吉布斯现象对采样信号信息的影响降至最低。在频谱分析方面,分析了FFT频谱分析算法能量泄露的原因,并应用加Hanning窗的方法对FFT算法的能量泄露进行了抑制,但实验表明频谱分析误差仍较大。为进一步减小频谱分析误差,研究了由加Hanning窗FFT算法与窗的谱函数之间的关系推导出的Hanning窗比值法,并对加Hanning窗FFT频谱结果进行校正,实验结果表明比值校正法明显提高了FFT频谱分析的精度。研究了以提高频率分辨率为目的的FT频谱细化算法,对FFT离散频谱连续化的实验结果进行了分析,并与比值校正法的实验结果进行比较,分析了两算法校正结果的差异以及两者仍然存在误差的原因。在信号分析算法实现方面,采用IQ数据格式使定点DSP完成了高精度的浮点运算,且提高了系统的实时性。
本文应用DSP模块对变频异步电机的电流信号进行了测试,测试结果表明DSP模块在强干扰的环境下,依然能够保持很高的测量精度,取得了良好的效果。
Testing technology has been applied to most areas of engineering, which has become an important indicator of productive efficiency and manufacturing capabilities. In order to improve productive efficiency and product performance, lots of countries strived to develop automated testing techniques. But the research on the automatic test system is late in our country, so most of sophisticated testing equipments are imported. Today, the emergence of virtual instrumentation gives us a new opportunity for development.
This paper has used DSP technology and virtual instrument technology to construct the signal processing and analysis system. It is the virtual oscilloscope module of helicopter automatic test system. The structure this paper has applied is different from the common structure of virtual oscilloscope. To avoid problems with large data transmission, the DSP module completed both data acquisition function and data processing function. It also improved real-time performance of the system.
This paper focuses on digital signal processing and analysis theoretics, and their implementation on the DSP module. On the aspect of digital filtering, MATLAB tools are applied to design Kaiser window FIR low-pass filter, and optimize the parameters to reduce the Gibbs phenomenon, in order to obtain accurate information on the sampling signal. On the aspect of spectrum analysis, the causes of the energy leaking problem for FFT analysis are analyzed. The method of additional Hanning window FFT algorithm is applied to suppress the energy leakage, but experiments show that the error is still large. In order to rectify the results of the FFT spectrum, many methods are studied, such as interpolation correcting method and FFT+FT method. Both experimental results were analyzed and compared, and the difference of the two algorithms was studied. The reasons of error by the two algorithms are also given out. On the aspect of the realization for signal analysis algorithms, IQ data format is used to complete a high-precision floating-point operations on the fixed-point DSP.
In this paper, DSP module is applied to test the current signal of the motor. Test results show that the DSP module was still able to maintain high accuracy in the environment of strong electromagnetic interference.
本文融合DSP技术和虚拟仪器技术,构建了测试信号处理分析系统,研制完成直升机自动测试系统中的虚拟示波器模块。不同于当前主流虚拟示波器结构“数据采集卡+上位机数据处理系统”,本文利用下位机DSP模块完成了数据采集功能和数据处理功能,避免了海量数据传输的问题,提高了系统实时性。上位机模块负责调度自动测试系统的各个模块的测试程序集。
本文重点研究数字信号处理分析的相关理论及其在DSP模块上的实现。在数字滤波方面,应用MATLAB工具对Kaiser窗FIR低通滤波器进行了参数优化和仿真验证,使窗函数旁瓣引起的吉布斯现象对采样信号信息的影响降至最低。在频谱分析方面,分析了FFT频谱分析算法能量泄露的原因,并应用加Hanning窗的方法对FFT算法的能量泄露进行了抑制,但实验表明频谱分析误差仍较大。为进一步减小频谱分析误差,研究了由加Hanning窗FFT算法与窗的谱函数之间的关系推导出的Hanning窗比值法,并对加Hanning窗FFT频谱结果进行校正,实验结果表明比值校正法明显提高了FFT频谱分析的精度。研究了以提高频率分辨率为目的的FT频谱细化算法,对FFT离散频谱连续化的实验结果进行了分析,并与比值校正法的实验结果进行比较,分析了两算法校正结果的差异以及两者仍然存在误差的原因。在信号分析算法实现方面,采用IQ数据格式使定点DSP完成了高精度的浮点运算,且提高了系统的实时性。
本文应用DSP模块对变频异步电机的电流信号进行了测试,测试结果表明DSP模块在强干扰的环境下,依然能够保持很高的测量精度,取得了良好的效果。
Testing technology has been applied to most areas of engineering, which has become an important indicator of productive efficiency and manufacturing capabilities. In order to improve productive efficiency and product performance, lots of countries strived to develop automated testing techniques. But the research on the automatic test system is late in our country, so most of sophisticated testing equipments are imported. Today, the emergence of virtual instrumentation gives us a new opportunity for development.
This paper has used DSP technology and virtual instrument technology to construct the signal processing and analysis system. It is the virtual oscilloscope module of helicopter automatic test system. The structure this paper has applied is different from the common structure of virtual oscilloscope. To avoid problems with large data transmission, the DSP module completed both data acquisition function and data processing function. It also improved real-time performance of the system.
This paper focuses on digital signal processing and analysis theoretics, and their implementation on the DSP module. On the aspect of digital filtering, MATLAB tools are applied to design Kaiser window FIR low-pass filter, and optimize the parameters to reduce the Gibbs phenomenon, in order to obtain accurate information on the sampling signal. On the aspect of spectrum analysis, the causes of the energy leaking problem for FFT analysis are analyzed. The method of additional Hanning window FFT algorithm is applied to suppress the energy leakage, but experiments show that the error is still large. In order to rectify the results of the FFT spectrum, many methods are studied, such as interpolation correcting method and FFT+FT method. Both experimental results were analyzed and compared, and the difference of the two algorithms was studied. The reasons of error by the two algorithms are also given out. On the aspect of the realization for signal analysis algorithms, IQ data format is used to complete a high-precision floating-point operations on the fixed-point DSP.
In this paper, DSP module is applied to test the current signal of the motor. Test results show that the DSP module was still able to maintain high accuracy in the environment of strong electromagnetic interference.
引文
1郑玉航,于海燕,孟飞.通用测控技术及其在军事领域中的应用.国防技术基础.2005(4):5~6
2李行善,于劲松.ATS自动测试系统及ATE技术.电子产品世界.2002(3):30~31
3周箭.虚拟仪器及其技术研究.浙江大学学报(工学版).2000(11):686~689
4李扬.高性能虚拟示波器的研究.工业仪表与自动化装置.1999(02):3~5
5王志辉.数字示波表控制电路及GUI的设计与实现.电子科技大学硕士论文.2003:10~12
6郭峻岭.基于DSP的信号采集与处理系统的设计与实现.武汉理工大学硕士论文.2009:5~10
7李晓琴.2Gsps数字存储示波器数据采集控制和数据处理软件设计.电子科技大学硕士论文.2005:4~8
8阎波,李广军.基于DSP+FPGA结构的嵌入式便携数字存储示波表.电测与仪表.2005,(11):31~33
9吕向阳.嵌入式数字存储示波器.仪表技术.2005,(1):36~38
10程言奎,李英.基于ARM9的嵌入式数字示波器参数测量模块的设计.计算机测量与控制.2008,16(12):1822~1825
11朱明武,李永新,卜雄洙.测试信号处理技术与分析.北京航空航天大学出版社,2006:68~89
12胡广书.数字信号处理—理论算法与实现.清华大学出版社,1997:115~167
13 D Kodak.Design of optimal finite wordlength FIR digital filters with linear phase.IEEE Trans on Assp.1980,28(3):304~308
14 Y C Lin,S P Parker.FIR filter design over a discrete power-of-two co-efficient space.IEEE Trans on Assp.1983,31(3):583~591
15 Kennedy J,Eberhart R C.Particle swarm optimizationA.Proc IEEE Int Conf on Neural NetworkC.Perth Australia IEEE,1995:1942~1948
16 Widrow B,Stearns S D.Adaptive Signal Processing.Englewood Cliffs, NJ:Prentice-Hall.1985:141~253
17 Haykin S S . Adaptive Filter Theory (3rd ed) . Englewood Cliffs , NJ :Prentice-Hall.1996:23~56
18丁康,张晓飞.频谱校正理论的发展.振动工程学报.2000,13(1):14~22
19丁康,陈建林,苏向荣.平稳和非平稳振动信号的若干处理方法及发展.振动工程学报.2003,16(1):1~10
20 Burgess J C.On digital spectrum analysis of periodic signals.Acoust.1975,58(3):556~567
21 Grandke T.Interpolation algorithms for discrete Fourier transofrms of weighted signals.IEEE Trans Instrum Meas.1983,32(2):350~355
22 Offelli C,Petri D.The influence of windowing on the accuracy of multifrequency signal parameter estimation.IEEE Trans Instum Meas.1992,41(2):256~261
23 Xie M,Ding K.Correction for the frequency anplirude and phase in FFT of harmonic sigial.Mechanical Systems and Signal Processing.1996,10(2):211~221
24谢明,丁康,莫克斌.频谱校正时谱线干涉的影响和判定方法.振动工程学报.1998,11(1):22~28
25谢明,丁康.频谱分析的校正方法.振动工程学报.1994,7(2):47~54
26 Huang D H.Phase error in fast Fourier transform analysis.Mechanical Systems and Signal Processing.1995,9(2):113~118
27余佳兵,史铁林,杨叔子.窗谱校正方法的实用峰值搜索算法研究.振动工程学报.1997,10(2):12~16
28丁康,谢明.提高FFT和谱分析速度和精度的方法.重庆大学学报.1992,15(2):51~57
29朱利民,熊有伦.一个通用的频谱误差校正快速算法.振动工程学报.2001,14(2):166~171
30丁康,江利旗.离散频谱的能量重心校正法.振动工程学报.2001,14(3):354~358
31焦新涛,丁康.加窗频谱分析的恢复系数及其求法.汕头大学学报,2003,18(3):42~47
32陈奎孚,焦群英,高小蓉.提高FFT谱质量的一种新方法.振动测试与诊断.1998,8(3):216~232
33 McMahon D T A,Brrett RF.An efficient method for the estimation of the frequency of a single tone in noise form the phase of discrete Fourier thansforms.Signal Process.1986 (11):169~177
34 Santamria I,Pantaleon C,Ibanez J.A comparative study of high-accuracy frequency estimation methods.Mechanical Systems and Signal Processing.2000,14(5):819~834
35 Ding K,Luo J K,Xie M.Timing-shifting correcting method of phase differencediscrete spectum.Applied Methematics and Mechanics.2002,23(7):819~827
36祁才君.数字信号处理技术的算法分析与应用.机械工业出版社,2005:13~89
37宗孔德,胡书广.数字信号处理.清华大学出版社,1998:56~81
38 (美)奥本海姆等,离散时间信号处理.刘树堂,黄建国.西安交通大学出版社,2001:34~39
39季虎,夏胜平,郁文贤.快速傅立叶变换算法概述.现在电子技术.2001,15(6):11~14
40陈建平,陆建新,李蕴华.快速傅立叶变换在数字信号处理器上的实现研究.南通工学院学报.2003,17(1):4~9
41 Danthez J M,Giroussens C,Aquilina R.The autocoherent spectrum:a useful spectral estimator for vibration analysis of rotating mathinery accurate setimation snd cancellation of pure tones.Mechanical Systems and Signal Processing.1998,12(6):753~768
42钱克矛,李川奇.频谱校正的线性调频变换方法,振动工程学报.2000,13(4):628~632
43 Borkowski.LIDFT-The DFT linear interpolation method.IEEE Trans Instrum Meas.2000,49(4):741~745
44 Mishra D K.ADC testing using inerpolated fasr Fourier transform (IFFT) technique.International Journal of Electronics.2003,90(7):459~469
45 Agrez D.Weighted multipoint interpolated DFT to improve amplitude estimation of multifrequency signal,IEEE Trans Instrum Meas.2002,51(2):287~292
46 Zhang R,Tjhung T T,Hu H H,et al.Window function and interpolation algorithm for OFDM frequency-offset correction . IEEE Transaction on Vehicular Technology.2003,52(3):654~670
47 Shi D F,Qu L S,Gindy N N.General interpolated fast Fourier transform:a new tool for diagnosing large rotating machinery . Journal of Vibration and Acoustics-Transactions of the ASME.2005,127(4):351~361
48 Texas Instruments.TMS320F2812 Digital Signal Prosessor Data Manual.2010.
49 Texas Instruments . TMS320x281x DSP Analog-to-Digital Converter (ADC) Reference Guide.2005.
50张春花.CAN总线简介及其应用研究.山西科技.2004,(1):15~17
51冯鹄.浅谈CAN总线的特点及应用.机械与电子.2009,(17):47~48
52方岚.印制电路板抗干扰设计浅析.集成电路通讯.2008,26(1):19~24
53周晗晓,袁慧梅.单片机系统的印制板设计与抗干扰技术.电子工艺技术.2004,26(6):261~265
54董强,倪健,刘云等.PCB板的布线设计及抗干扰设计.舰船科学技术.2006,28(2):57~63
55肖麟芬.印制电路板的抗干扰设计.电子工程师.2005,31(3):20~22
2李行善,于劲松.ATS自动测试系统及ATE技术.电子产品世界.2002(3):30~31
3周箭.虚拟仪器及其技术研究.浙江大学学报(工学版).2000(11):686~689
4李扬.高性能虚拟示波器的研究.工业仪表与自动化装置.1999(02):3~5
5王志辉.数字示波表控制电路及GUI的设计与实现.电子科技大学硕士论文.2003:10~12
6郭峻岭.基于DSP的信号采集与处理系统的设计与实现.武汉理工大学硕士论文.2009:5~10
7李晓琴.2Gsps数字存储示波器数据采集控制和数据处理软件设计.电子科技大学硕士论文.2005:4~8
8阎波,李广军.基于DSP+FPGA结构的嵌入式便携数字存储示波表.电测与仪表.2005,(11):31~33
9吕向阳.嵌入式数字存储示波器.仪表技术.2005,(1):36~38
10程言奎,李英.基于ARM9的嵌入式数字示波器参数测量模块的设计.计算机测量与控制.2008,16(12):1822~1825
11朱明武,李永新,卜雄洙.测试信号处理技术与分析.北京航空航天大学出版社,2006:68~89
12胡广书.数字信号处理—理论算法与实现.清华大学出版社,1997:115~167
13 D Kodak.Design of optimal finite wordlength FIR digital filters with linear phase.IEEE Trans on Assp.1980,28(3):304~308
14 Y C Lin,S P Parker.FIR filter design over a discrete power-of-two co-efficient space.IEEE Trans on Assp.1983,31(3):583~591
15 Kennedy J,Eberhart R C.Particle swarm optimizationA.Proc IEEE Int Conf on Neural NetworkC.Perth Australia IEEE,1995:1942~1948
16 Widrow B,Stearns S D.Adaptive Signal Processing.Englewood Cliffs, NJ:Prentice-Hall.1985:141~253
17 Haykin S S . Adaptive Filter Theory (3rd ed) . Englewood Cliffs , NJ :Prentice-Hall.1996:23~56
18丁康,张晓飞.频谱校正理论的发展.振动工程学报.2000,13(1):14~22
19丁康,陈建林,苏向荣.平稳和非平稳振动信号的若干处理方法及发展.振动工程学报.2003,16(1):1~10
20 Burgess J C.On digital spectrum analysis of periodic signals.Acoust.1975,58(3):556~567
21 Grandke T.Interpolation algorithms for discrete Fourier transofrms of weighted signals.IEEE Trans Instrum Meas.1983,32(2):350~355
22 Offelli C,Petri D.The influence of windowing on the accuracy of multifrequency signal parameter estimation.IEEE Trans Instum Meas.1992,41(2):256~261
23 Xie M,Ding K.Correction for the frequency anplirude and phase in FFT of harmonic sigial.Mechanical Systems and Signal Processing.1996,10(2):211~221
24谢明,丁康,莫克斌.频谱校正时谱线干涉的影响和判定方法.振动工程学报.1998,11(1):22~28
25谢明,丁康.频谱分析的校正方法.振动工程学报.1994,7(2):47~54
26 Huang D H.Phase error in fast Fourier transform analysis.Mechanical Systems and Signal Processing.1995,9(2):113~118
27余佳兵,史铁林,杨叔子.窗谱校正方法的实用峰值搜索算法研究.振动工程学报.1997,10(2):12~16
28丁康,谢明.提高FFT和谱分析速度和精度的方法.重庆大学学报.1992,15(2):51~57
29朱利民,熊有伦.一个通用的频谱误差校正快速算法.振动工程学报.2001,14(2):166~171
30丁康,江利旗.离散频谱的能量重心校正法.振动工程学报.2001,14(3):354~358
31焦新涛,丁康.加窗频谱分析的恢复系数及其求法.汕头大学学报,2003,18(3):42~47
32陈奎孚,焦群英,高小蓉.提高FFT谱质量的一种新方法.振动测试与诊断.1998,8(3):216~232
33 McMahon D T A,Brrett RF.An efficient method for the estimation of the frequency of a single tone in noise form the phase of discrete Fourier thansforms.Signal Process.1986 (11):169~177
34 Santamria I,Pantaleon C,Ibanez J.A comparative study of high-accuracy frequency estimation methods.Mechanical Systems and Signal Processing.2000,14(5):819~834
35 Ding K,Luo J K,Xie M.Timing-shifting correcting method of phase differencediscrete spectum.Applied Methematics and Mechanics.2002,23(7):819~827
36祁才君.数字信号处理技术的算法分析与应用.机械工业出版社,2005:13~89
37宗孔德,胡书广.数字信号处理.清华大学出版社,1998:56~81
38 (美)奥本海姆等,离散时间信号处理.刘树堂,黄建国.西安交通大学出版社,2001:34~39
39季虎,夏胜平,郁文贤.快速傅立叶变换算法概述.现在电子技术.2001,15(6):11~14
40陈建平,陆建新,李蕴华.快速傅立叶变换在数字信号处理器上的实现研究.南通工学院学报.2003,17(1):4~9
41 Danthez J M,Giroussens C,Aquilina R.The autocoherent spectrum:a useful spectral estimator for vibration analysis of rotating mathinery accurate setimation snd cancellation of pure tones.Mechanical Systems and Signal Processing.1998,12(6):753~768
42钱克矛,李川奇.频谱校正的线性调频变换方法,振动工程学报.2000,13(4):628~632
43 Borkowski.LIDFT-The DFT linear interpolation method.IEEE Trans Instrum Meas.2000,49(4):741~745
44 Mishra D K.ADC testing using inerpolated fasr Fourier transform (IFFT) technique.International Journal of Electronics.2003,90(7):459~469
45 Agrez D.Weighted multipoint interpolated DFT to improve amplitude estimation of multifrequency signal,IEEE Trans Instrum Meas.2002,51(2):287~292
46 Zhang R,Tjhung T T,Hu H H,et al.Window function and interpolation algorithm for OFDM frequency-offset correction . IEEE Transaction on Vehicular Technology.2003,52(3):654~670
47 Shi D F,Qu L S,Gindy N N.General interpolated fast Fourier transform:a new tool for diagnosing large rotating machinery . Journal of Vibration and Acoustics-Transactions of the ASME.2005,127(4):351~361
48 Texas Instruments.TMS320F2812 Digital Signal Prosessor Data Manual.2010.
49 Texas Instruments . TMS320x281x DSP Analog-to-Digital Converter (ADC) Reference Guide.2005.
50张春花.CAN总线简介及其应用研究.山西科技.2004,(1):15~17
51冯鹄.浅谈CAN总线的特点及应用.机械与电子.2009,(17):47~48
52方岚.印制电路板抗干扰设计浅析.集成电路通讯.2008,26(1):19~24
53周晗晓,袁慧梅.单片机系统的印制板设计与抗干扰技术.电子工艺技术.2004,26(6):261~265
54董强,倪健,刘云等.PCB板的布线设计及抗干扰设计.舰船科学技术.2006,28(2):57~63
55肖麟芬.印制电路板的抗干扰设计.电子工程师.2005,31(3):20~22