【摘要】：轉(zhuǎn)速測(cè)量與工業(yè)生產(chǎn)、國(guó)防建設(shè)和科研等密切相關(guān)�；诳臻g濾波技術(shù)的轉(zhuǎn)速遙測(cè)系統(tǒng)具有結(jié)構(gòu)簡(jiǎn)單、非接觸、可以遙測(cè)的特點(diǎn),有良好的應(yīng)用前景。在空間濾波轉(zhuǎn)速遙測(cè)系統(tǒng)中,從差分空間濾波傳感器輸出的準(zhǔn)正弦信號(hào)中提取其中心頻率,再用中心頻率計(jì)算出轉(zhuǎn)速。從準(zhǔn)正弦信號(hào)中瞬時(shí)準(zhǔn)確地提取出中心頻率是該系統(tǒng)能準(zhǔn)確遙測(cè)瞬時(shí)轉(zhuǎn)速的關(guān)鍵。然而,空間濾波信號(hào)是窄帶非平穩(wěn)的,其幅度和相位都有一定的隨機(jī)性,這使得準(zhǔn)確提取空間濾波信號(hào)的瞬時(shí)中心頻率很困難。為解決該難題,根據(jù)準(zhǔn)正弦信號(hào)的特點(diǎn)和小波變換的時(shí)頻局部性,提出了基于復(fù)小波變換的中心頻率提取方法(WT方法)。在該方法中,先根據(jù)中心頻率的預(yù)測(cè)值構(gòu)造出有不同中心頻率的復(fù)小波,用復(fù)小波族對(duì)準(zhǔn)正弦信號(hào)進(jìn)行復(fù)小波變換并取其模值,以最大模值對(duì)應(yīng)的小波中心頻率作為信號(hào)的中心頻率。為簡(jiǎn)單有效地實(shí)現(xiàn)復(fù)小波變換,用高斯函數(shù)的m階和m+1階導(dǎo)數(shù)作為一對(duì)正交小波,用該對(duì)正交小波分別作為實(shí)部和虛部而構(gòu)成復(fù)母小波;用高斯函數(shù)任意階導(dǎo)數(shù)的頻譜經(jīng)離散傅里葉逆變換得到復(fù)小波的時(shí)域序列,以高效地構(gòu)建出復(fù)小波。用仿真實(shí)驗(yàn)和空間濾波器信號(hào),驗(yàn)證了所提出的中心頻率提取方法及其性能。在仿真實(shí)驗(yàn)中用WT方法提取已知頻率正弦信號(hào)的頻率,通過(guò)與快速傅里葉變換方法(FFT方法)、過(guò)零點(diǎn)周期方法(CZ方法)提取的正弦信號(hào)頻率比較,得出了WT方法能夠用于提取信號(hào)頻率的結(jié)論。在用實(shí)際空間濾波信號(hào)進(jìn)行的實(shí)驗(yàn)中,分別采用對(duì)稱實(shí)小波(包括奇、偶對(duì)稱實(shí)小波)和復(fù)小波進(jìn)行了中心頻率的提取,通過(guò)和FFT方法、CZ方法的實(shí)驗(yàn)結(jié)果比較,驗(yàn)證了采用實(shí)小波變換不能提取出空間濾波信號(hào)中心頻率,也驗(yàn)證了WT方法比常用的FFT方法、CZ方法瞬時(shí)性強(qiáng)、精度高的結(jié)論。這樣,本文有效的解決了瞬時(shí)、準(zhǔn)確的提取準(zhǔn)正弦信號(hào)中心頻率的難題。
[Abstract]:Rotational speed measurement is closely related to industrial production, national defense construction and scientific research. The rotational speed telemetry system based on spatial filtering technology has the characteristics of simple structure, non-contact, and can be telemetry, so it has a good application prospect. In the space filtering rotational speed telemetry system, the center frequency is extracted from the quasi sinusoidal signal output from the differential spatial filter sensor, and the rotational speed is calculated by the center frequency. Instantaneous and accurate extraction of center frequency from quasi-sinusoidal signal is the key to accurate telemetry of instantaneous rotational speed. However, the spatial filtering signal is nonstationary in narrow band, and its amplitude and phase are both random, which makes it difficult to accurately extract the instantaneous center frequency of the spatial filter signal. In order to solve this problem, according to the characteristics of quasi-sinusoidal signal and the time-frequency localization of wavelet transform, a method of center frequency extraction based on complex wavelet transform (WT method) is proposed. In this method, the complex wavelet with different central frequency is constructed according to the predicted value of the center frequency, and the complex wavelet transform is performed on the sinusoidal signal by using the complex wavelet family and the modulus of the complex wavelet transform is obtained. The wavelet center frequency corresponding to the maximum modulus value is taken as the central frequency of the signal. In order to realize complex wavelet transform simply and effectively, the m order and m 1 derivative of Gao Si function are used as a pair of orthogonal wavelets, and this pair of orthogonal wavelets are used as real part and imaginary part respectively to form complex mother wavelets. The time-domain sequence of complex wavelet is obtained by inverse discrete Fourier transform with the spectrum of arbitrary derivative of Gao Si function, and the complex wavelet is constructed efficiently. Simulation experiments and spatial filter signals are used to verify the proposed method and its performance. In the simulation experiment, the frequency of the known frequency sinusoidal signal is extracted by WT method. The frequency of the sinusoidal signal is compared with that extracted by the fast Fourier transform method (FFT method) and the zero-crossing period method (CZ method). It is concluded that the WT method can be used to extract the signal frequency. In the experiments using real spatial filtering signals, symmetric real wavelets (including odd and even symmetric real wavelets) and complex wavelets are used to extract the center frequencies respectively. The experimental results are compared with the experimental results of FFT method and CZ method. It is verified that the real wavelet transform can not extract the center frequency of the spatial filter signal, and the conclusion that WT method is more instantaneous and accurate than the usual FFT method is verified. In this way, the problem of instantaneous and accurate extraction of center frequency of quasi-sinusoidal signal is solved effectively in this paper.
【學(xué)位授予單位】：重慶理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2016
【分類號(hào)】：TN911.7

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 石忠衛(wèi);沈曉鵬;王洋;梁麗榮;張寧波;;基于Mathematica 6.0的空間濾波實(shí)驗(yàn)演示[J];物理實(shí)驗(yàn);2008年11期

2 少川;;空間濾波器及其應(yīng)用[J];激光與紅外;1975年09期

3 秦忠宇;空間濾波在雷達(dá)中的應(yīng)用[J];系統(tǒng)工程與電子技術(shù);1990年02期

4 鄭麗娜;;空間濾波測(cè)速的發(fā)展及濾波效應(yīng)研究[J];數(shù)字技術(shù)與應(yīng)用;2013年10期

5 陳城釗;;光學(xué)空間濾波實(shí)驗(yàn)的微機(jī)模擬演示[J];韓山師范學(xué)院學(xué)報(bào);2005年06期

6 林浩亮;劉南生;魏升;袁尤智;汪巖峰;;窗函數(shù)對(duì)光學(xué)空間濾波效果的影響分析[J];光學(xué)與光電技術(shù);2007年06期

7 侯蘭田;;相減技術(shù)及其在空間濾波上的應(yīng)用[J];激光與紅外;1978年11期

8 朱自強(qiáng) ,郭履容;一種方向性濾波與低頻濾波相結(jié)合的空間濾波方法[J];四川大學(xué)學(xué)報(bào)(自然科學(xué)版);1981年02期

9 張銘,楊萬(wàn)麟,李樂(lè)民;空間濾波預(yù)處理法及其在單次快攝陣處理中的應(yīng)用[J];電子科學(xué)學(xué)刊;1992年02期

10 李晶;趙海燕;;光柵空間濾波方法實(shí)現(xiàn)顯微光切片[J];生物醫(yī)學(xué)工程學(xué)雜志;2009年06期

相關(guān)會(huì)議論文 前2條

1 曹麗;尹朝征;劉杰;路加;;空間濾波測(cè)速的視頻方法[A];中國(guó)儀器儀表學(xué)會(huì)第三屆青年學(xué)術(shù)會(huì)議論文集（上）[C];2001年

2 李宏升;張敏;廖延彪;陳凡秀;王靜;;利用光學(xué)廣義傅里葉變換和空間濾波實(shí)現(xiàn)亞毫米結(jié)構(gòu)的三維形貌測(cè)量[A];2011西部光子學(xué)學(xué)術(shù)會(huì)議論文摘要集[C];2011年

相關(guān)碩士學(xué)位論文 前9條

1 王瑞敏;基于穩(wěn)態(tài)視覺(jué)誘發(fā)電位的腦機(jī)接口的研究[D];南京理工大學(xué);2015年

2 陳陽(yáng);自分度非接觸旋轉(zhuǎn)量傳感的方向辨識(shí)方法研究[D];重慶理工大學(xué);2015年

3 朱志雄;基于光電池線陣對(duì)的瞬時(shí)轉(zhuǎn)速遙測(cè)原理及特性研究[D];重慶理工大學(xué);2016年

4 陳閃閃;空間濾波轉(zhuǎn)速遙測(cè)系統(tǒng)的信號(hào)處理及其實(shí)現(xiàn)方法[D];重慶理工大學(xué);2016年

5 陳波;心臟磁場(chǎng)信號(hào)的空間濾波[D];同濟(jì)大學(xué);2007年

6 阿不力孜·阿布都艾尼;基于消激光散斑空間濾波實(shí)驗(yàn)儀的改進(jìn)研制[D];合肥工業(yè)大學(xué);2012年

7 林浩亮;強(qiáng)背景光的高頻目標(biāo)物頻譜分析及信息提取研究[D];南昌大學(xué);2007年

8 張登科;快速序列視覺(jué)呈現(xiàn)系統(tǒng)及相關(guān)處理算法研究[D];清華大學(xué);2012年

9 王仁杰;衍射光柵空間濾波理論與光柵設(shè)計(jì)、制作實(shí)驗(yàn)方法研究[D];東北師范大學(xué);2015年

，

本文編號(hào)：2295785