Abstract:For the phase difference measurement errors based on DFT(Discrete Fourier Transform) and DTFT (Discrete Time Fourier Transform) methods with negative frequency contribution under white noise background, the formulas for evaluating variance of phase difference measurement DFT and DTFT methods are presented by using error theory. Under the condition of negative frequency contribution, the calculations are carried out for different leakage error coefficients, sampling sequence lengths and signal-noise-ratios (SNR). The simulation results are coinciding with those calculated results using the presented formulas, which show the correctness of the phase measurement error analysis formula. The accuracy of DFT and DTFT based phase difference measurement methods with negative frequency contribution could be improved effectively by enhancing the frequency estimation accuracy, increasing the sampling sequence length, and improving the SNR. When the sampling sequence length is more than 2048 or SNR is greater than 5dB, the accuracy of phase difference measurement is improved limited. The DTFT based phase measurement method is more sensitive to frequency estimation accuracy.
涂亚庆,李 明,沈廷鳌,张海涛 . 计及负频率的DFT与DTFT相位差测量误差分析[J]. 振动与冲击, 2015, 34(20): 85-91.
TU Ya-qing,LI Ming,SHEN Ting-ao,ZHANG Hai-tao. Error analysis of DFT and DTFT based phase difference measurement with negative frequency contribution. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(20): 85-91.
[1] 刘灿涛,赵伟,袁俊. 基于数字相关原理的相位差测量新方法[J]. 计量学报, 2002, 23(3): 219-223.
LIU Can-tao, ZHAO Wei, YUAN Jun. A new method for phase difference measurement based on digital correlation theory[J]. Acta Metrologica Sinica, 2002, 23(3): 219-223.
[2] 郑胜峰,陈素明,狄金海,等. 一种基于多重互相关的相位差测量方法[J]. 宇航计测技术, 2012, 32(1): 34-40.
ZHENG Sheng-feng, CHEN Su-ming, DI Jin-hai, et al. Phase difference measurement of sinusoidal signal based on multi-layer cross-correlation[J]. Journal of Astronautic Metrology and Measurement, 2012, 32(1): 34-40.
[3] 江亚群,何怡刚. 基于加窗DFT的相位差高精度测量算法[J]. 电路与系统学报, 2005, 10(2): 112-116.
JIANG Ya-qun, HE Yi-gang. New algorithm for high- accuracy phase difference measurement based on windowed DFT[J]. Journal of Circuits and Systems,2005,10(2):112- 116.
[4] 陈孔阳. 一种基于改进DFT算法的相位差测量研究[J]. 微计算机信息, 2012, 28(4): 142-144.
CHEN Kong-yang. A research on phase difference measurement based on improved DFT algorithm[J]. Microcomputer Information, 2012, 28(4): 142-144.
[5] 张海涛,涂亚庆. 计及负频率影响的科里奥利质量流量计信号处理方法[J]. 仪器仪表学报, 2007, 3(3): 539-544.
ZHANG Hai-tao, TU Ya-qing. New signal processing method with negative frequency contribution for Coriolis mass flowmeter[J]. Chinese Journal of Scientific Instrument, 2007, 3(3): 539-544.
[6] 沈廷鳌,涂亚庆,张海涛,等. 科氏流量计的时变信号处理方法[J]. 重庆大学学报, 2013, 36(4): 93-98.
SHEN Ting-ao, TU Ya-qing, ZHANG Hai-tao, et al. A time- varying signal processing method for Coriolis Mass Flowmeter[J]. Journal of Chongqing University, 2013, 36(4): 93-98.
[7] 毛育文,涂亚庆,张海涛,等. 计及负频率影响的频谱分析方法及研究进展[J]. 电测与仪表, 2011, 48(5): 27-32.
MAO Yu-wen, TU Ya-qing, ZHANG Hai-tao,et al. Advances and trends in spectrum analysis methodology with negative frequency contribution[J]. Electrical Measurement & Instrumentation, 2011, 48(5): 27-32.
[8] 陈奎孚,张森文,郭幸福. 消除负频率影响的频谱校正[J]. 机械强度, 2004, 26(1): 25-28.
CHEN Kui-fu, ZHANG Sen-wen, GUO Xing-fu. Spectrum rectifying with negative frequency contribution eliminating[J]. Journal of Mechanical Strenth, 2004, 26(1): 25-28.
[9] 毛育文,涂亚庆,武建军. 基于小波和灰色关联度的消除负频率干涉方法[J]. 电子测量与仪器学报, 2012, 26(9): 805- 811.
MAO Yu-wen, TU Ya-qing, WU Jian-jun. New method to eliminate negative frequency interference based on wavelet transformation and grey correlation degree theory[J]. Journal of Electronic Measurement and Instrument, 2012, 26(9): 805- 811.
[10] 毛育文,涂亚庆,张海涛,等. 极低频信号的一种离散频谱校正新方法[J]. 振动工程学报,2012,25(4): 474-480.
MAO Yu-wen, TU Ya-qing, ZHANG Hai-tao, et al. A discrete spectrum correction metod for ultra low frequency signals[J].Journal of Vibration Engineering, 2012, 25(4): 474-480.
[11] 陈奎孚,王建立,张森文. 低频成份的频谱校正[J]. 振动工程学报, 2008, 21(1): 38-42.
CHEN Kui-fu, WANG Jian-li, ZHANG Sen-wen. Correction of frequency spectrum for low frequency components[J]. Journal of Vibration Engineering, 2008, 21(1): 38-42.
[12] 毛育文,涂亚庆,张海涛,等.计及负频率的极高频信号离散频谱校正新方法[J].振动、测试与诊断, 2012,32(3):477-482.
MAO Yu-wen, TU Ya-qing, ZHANG Hai-tao, et al. New discrete spectrum correction method with negative frequency contribution for ultra high frequency signals[J]. Journal of vibration, Measurement & Diagnosis. ,2012,32(3):477-482.
[13] 谭思炜,任志良,孙常存. 全相位FFT相位差频谱校正法改进[J]. 系统工程与电子技术, 2013, 35(1): 34-39.
TAN Si-wei, REN Zhi-liang, SUN Chang-cun. Improvement of phase difference correcting spectrum method based on all-phase FFT[J]. Systems Engineering and Electronics, 2013, 35(1): 34-39.
[14] 张海涛,涂亚庆. 基于FFT的一种计及负频率影响的相位差测量新方法[J]. 计量学报, 2008,29(2):168-171.
ZHANG Hai-tao, TU Ya-qing. A new method for phase difference measurement based on FFT with Negative frequency contribution[J]. Acta Metrologica Sinica, 2008, 29(2): 168-171.
[15] 张海涛,涂亚庆. 基于DTFT的一种低频振动信号相位差测量新方法[J]. 振动工程学报, 2007, 20(2): 180-184.
ZHANG Hai-tao, TU Ya-qing. A new phase difference measurement method for low-frequency vibration signals based on DTFT[J]. Journal of Vibration Engineering, 2007, 20(2): 180-184.
[16] 张海涛,涂亚庆,牛鹏辉. 相位差测量的FFT法和DTFT法误差分析[J]. 电子测量与仪器学报, 2007, 21(3):61-65.
ZHANG Hai-tao, TU Ya-qing, NIU Peng-hui. Error analysis of phase difference measurement using FFT-based method and DTFT-based method[J]. Journal of Electronic Measurement and Instrument. 2007, 21(3):61-65.
[17] 齐国清. 利用FFT相位差校正信号频率和初相估计的误差分析[J]. 数据采集与处理, 2003, 18(1):7-11.
QI Guo-qing. Error analysis of frequency and phase estimations based on phase difference of segmented FFTs[J]. Journal of Data Acquisition & Processing, 2003, 18(1):7-11.
[18] Kay S M. Fundamentals of statistical processing volume 1: estimation theory[M].New Jersey: A Simon & Schuster Company, 1993: 294-295.