方差譜 的英文怎麼說
中文拼音 [fāngchāpǔ]
方差譜
英文
variance spectrum-
And then facing the problem of the channel estimation of the adaptive modulation system, we conclude out the channel estimation algorithms on maximum likelihood ( ml ) estimation and maximum a posteriori ( map ) estimation under the condition of flat fading channel and selective fading channel in detail. to meet flat fading channel, we simulate the relationship of the ratio between the error covariance in map estimation and ml estimation and pilot symbol message length. the conclusion can be drawn from these results
接著，對自適應調制系統中的通道估計問題難點，詳細推導了平衰落通道條件下和選擇性衰落通道條件下最大似然（ ml ）估計和最大后驗概率（ map ）估計演算法，針對平衰落通道，我們模擬了map估計和ml估計的方差與導頻符號長度的關系，模擬結果表明，錯誤方差受多譜勒頻率的變化影響最大，並且對實際的自適應調制系統，導頻符號長度的取值超過20個符號長度時， map通道估計明顯優于ml通道估計。And understanding and studying the spectral features and variation rules of geo - targets in the experimental area, raising that it is the basis of geo - targets information collection with imaging spectrometer data to understand spectral features and variation rules of geo - targets, realizing that in a great extent spectral - integrated - form - based classification method can remove the phenomenon of " different spectrum with same objects " resulted from reflection ratio curve translation because of the angle change among sensor, targets and observation direction, and the average and variance images can be introduced to solve the problem of two kinds of geo - target with similar spectral forms and much different values of whole reflection ratio. it is suggested that " red edge " range bands of vegetation, which has close relationship with vegetation cover and biomass, is the main characteristic bands and important basis for careful vegetation classification and quantitative retrieval, and pixel - based derivative spectral analysis is very useful for removing the effects of soil background values and quantitatively retrieving vegetation biomass and cover. the remote sense quantitative retrieval model is developed for main appraisable factors of desertification monitoring assessment with imaging spectrometer data and then the applicability of model is analyzed
研究結果如下：首先針對荒漠化地區的地物特徵，對高光譜數據不同波段的數據質量、波段組合進行了評價，提出了適用於荒漠化監測的基本波段選擇集；初步了解和掌握了研究地區的地物光譜特性及變異規律，進一步明確了掌握地物光譜特徵和變異規律是用成像光譜儀數據提取地物信息的基礎；發現了基於光譜整體形狀的分類方法在很大程度上能夠消除由於傳感器、地物目標觀測方向之間的角度變化引起的反射率曲線整體平移的「同物異譜」現象，對于譜形相似而整體反射率的值相差較大的兩類地物，通過引入均值和方差圖像參與分類得到解決；研究還表明在植被「紅邊」范圍內的波段是進行荒漠化監測的主要特徵波段，這些波段與植被生物量和蓋度都有密切的關系，是開展精細植被分類研究和植被定量反演的重要基礎；像元的導數光譜分析可以消除土壤背景的影響，是進行植被生物量和蓋度定量反演的有力工具；建立了荒漠化監測主要評價因子的定量反演模型，並分析了模型的適用性。Space spectrum estimation technology has a comprehensive perspective in the military and civilian applications, the estimation method based on higher - order statistics has better performance than that based on covariance. firstly, the thesis introduces the definitions and the attributes of the higher - order statistics
空間譜估計技術在軍用和民用方面都有著廣泛的應用情景，將高階統計量應用於空間譜估計，所得到的性能要好於基於協方差的空間譜估計。If the covariance stationary processes are one dimension, for given data, covariance function and spectral density function can be estimated, and there is no need to select kernel function and its parameters
如果協方差平穩隨機過程的狀態是一維的，對給定的樣本點，給出了協方差函數的估計和其對應譜（密度）函數估計，而不必選擇核函數及其參數。For the given sample points, and matrix formed by covariance function with sample points as parameters, when the number of sample points approaches infinite, it is proven that this matrix spectrum will approach the spectral approach theorem for positive - definite kernel of integral equation
對給定的樣本點，由樣本點為變量的協方差函數構成的矩陣，當樣本點個數趨于無窮大時，證明此矩陣譜逼近於積分方程正定核的譜逼近定理。The equations of the mean value functions and the covariance functions are established for dynamical systems whose inputs are fuzzy stochastic processes. an existence and uniqueness theorem of ito fuzzy stochastic differential equations is proved, some explicit representations of solutions and the equations of statistical characteristics are deduced for linear fuzzy stochastic differential equations, and numerical methods to nonlinear fuzzy stochastic differential equations are proposed, the conditions for stability and observability of fuzzy linear systems are derived. the kalman filter algorithms of linear fuzzy stochastic systems are brought forward
主要成果包括：提出了模糊隨機變量協方差和反向協方差的概念；研究了二階模糊隨機變量的均方收斂性，並在此基礎上得到了均方模糊隨機分析、平穩模糊隨機過程及其譜分解的若干定理；根據均方模糊隨機分析理論，得到了輸入為模糊隨機過程的線性系統的輸出輸入統計特徵關系方程；證明了ito型模糊隨機微分方程解的存在唯一性，並給出了ito型線性模糊隨機微分方程解的表達式，統計特徵方程以及非線性模糊隨機微分方程的數值解法；得到了模糊線性系統的穩定性和可觀性條件、線性模糊隨機系統統計特徵方程和線性模糊隨機系統的kalman濾波演算法；研究了當觀測值是模糊數據時，線性回歸模型的建立。The relationship of the spca, pca and kpca are established. according to the covariance stationary processes, spca arithmetic also has certain stability and convergent similar to pca arithmetic
由協方差平穩過程，得到譜主成分分析演算法也有類似於主成分分析演算法的穩定性和收斂性。In this thesis, based on principal component analysis ( pca ), covariance stationary processes and spectral analysis theory of linear operator, spectral principal component analysis ( spca ) is put forward
在主成分分析的基礎上，基於協方差平穩過程理論和線性運算元譜分析理論，本文提出了譜主成分分析。The signal process function of the software include these function : digital filter, windowing, auto - correlation function and cross - correlation function, mean and variance, probability density function and probability distribution function statistic ; auto - power spectrum, cross - power spectrum, frequency response function, coherence function, cepstrum analysis based on fft ( fast fourier transfer ) ; joint time - frequency analysis based on stft ( short - time fourier transfer )
軟體的處理功能包括：數字濾波、時域加窗、自相關與互相關處理、均值和方差計算、概率密度和概率分佈函數計算；在快速傅立葉變換（ fft ）基礎上計算自功率譜、互功率譜、頻率響應函數、相干函數、倒頻譜分析；基於短時傅立葉變換（ stft ）的聯合時頻分析等。Tricepstrum equalization algorithm ( btea ) and super - exponential ( se ) algorithm based on block data estimation is studied, and these algorithms use hos explicitly. their performance, such as estimation variance and bias, is analyzed. a kind of sparse cross cumulant and sparse equalizer is proposed to simplify the se algorithm, and the simulating results show efficient reduction in complication
?研究了幾種直接使用高階統計量的演算法，包括基於數據段估計的倒三譜演算法和超指數演算法，分析了演算法的估計方差和偏差等性能；由於超指數演算法計算量較大，不利於實時均衡，利用水聲通道的稀疏性，提出了一種基於稀疏互四階累積量和稀疏權的演算法，有效降低了超指數演算法的計算量。Then the periodic properties of geocenter motion in the x, y, z components are summarized. considering the statistical precision of the gps observations, the geometrical distribution of gps stations and their physical stablility, a new method to determine the parameters of geocenter motion is studied and analyzed. in order to have a better understanding of its effect on the height datum origin, the rule of geocenter motion in the horizontal and vertical components are also analyzed and some useful conclusions are drawn
提出了將譜分析與抗差估計相結合的抗差譜分析方法，並用該方法分析了地心運動時間序列的主要周期特性；為合理地確定地心運動參數，詳細研究與分析了一種新的定權方法對求解地心運動參數的作用，該方法充分利用了gps觀測量的統計精度、點位的幾何分佈以及物理穩定性；為了明確地心運動導致的高程基準的變化，分析了地心運動對地面點的水平分量和垂直分量的影響規律。The ga ( genetic algorithm ) is applied to solve the optimal parameters of the mtmd appended in cabin in frequency - domain. 4. the dynamic responses of the cabin with different mtmd are compared under different wind speed
以基於davenport風速譜的位移諧響應根方差為目標函數，應用遺傳演算法，在頻域上獲得了mtmd的最優參數值。There are mainly two type of algorithms used for spatial spectrum estimation : one is those based on bayesian maximum likelihood method, like the ml ( maximum likelihood ) algorithm, maximum entropy method and etc., the others are based on the spatial decomposition or projection of correlation matrix, this kind of algorithm include vector characterization method, music ( multiple signal classification ) algorithm, projection matrix method, etc. music is a classical spatial spectrum estimation algorithm that has a super high resolution and is widely used today, however, it cannot estimate doa of signals that are correlated
空間譜估計的演算法大致分兩大類:一是基於極大似然估計和最大后驗概率估計統計理論的演算法，包括:極大似然估計法（ ml ） 、最大熵法等;另一類是基於對協方差矩陣進行子空間分解或投影的演算法，包括:矢量特徵法、多重信號分類法（ music ） 、投影矩陣法等。其中， music法是一種經典的空間譜估計主流演算法，具有超強的分辨性能，但它無法實現對相干信號進行測向分辨。The statistic of wavelet transform coefficient algorithm can solve the periodic noise, high - energy noise and some non - gauss noise simply and effectively ; bi - spectrum can acquire more information from the original signal than power - spectrum, detect more information except from range and restrain the gauss noise. short - time speech signal can be considered as stationary and with periodic non - gauss signal, so we can make use of bi - spectrum to obtain the speech character and separate the speech and noise and detect morse telegraph signal ; complex number spectrum variance algorithm is put forward based on the deeply observing speech data, it is a new algorithm, experiment show that it is simple, effective
統計演算法在解決周期信號、高能噪聲和高斯信號方面有獨特之處，能簡單有效提取以上噪聲的特徵;雙譜能夠提供比功率譜更多的有用信息，有效地檢測信號幅度之外的其它信息，並能有效抑制高斯噪聲，短時語音信號一般認為是平穩且有一定的周期性的非高斯信號，因而可以利用雙譜來提取語音信號特性並實現信噪分離;復數譜方差演算法是在對語音信號進行深入觀察和分析的基礎上而提出來的一種全新的語音特徵提取方法，此方法簡單而有效的提取了語音、噪聲的特徵以及檢測莫爾斯信號，基於實驗表明，該演算法取得了很好的效果。Studies have been made on arithmetic realization of apsd estimate in a high - speed detect system, since the way of calculating cpsd is only a little different from that of calculating apsd
鑒于互功率譜密度估計演算法只需將自功率譜密度估計演算法中的自協方差函數換成互協方差函數，本文僅研究和討論了自功率譜密度估計演算法及其實現。First, the thesis introduces the definitions and the attributes of the higher - order statistics. it is insensitive to additive gaussian noise ( white or colored ), which is what we base on to doa problems. then two doa estimation algorithms based on higher - order statistics are presented, one is that forming cumulant matrix pencil used in esprit to estimate doa problems, the other is spectrum estimation method for doa estimation based on the eigenstructure analysis of the fourth - order cumulant, and comparing the effects of the estimation to conventional covariance - based doa algorithms "
論文首先對高階統計量的定義和性質作了介紹，特別指出了高階統計量對加性高斯噪聲（白色或有色）不敏感，這是我們利用它進行波達方向估計的理論依據，然後文中提出了兩種基於高階統計量的波達方向估計方法，一種是利用子空間旋轉不變技術構造四階累積量矩陣進行估計的方法，另一種是基於四階累積量陣特徵分解的空間譜估計測向方法，並將它們的估計效果與傳統協方差方法的效果進行比較。Through the i 、 q component of ipix radar sea clutter data " s histogram analyses and by skewness and kurtosis computed, it is been shown that sea clutter amplitude is not rayleigh distribution ; through the comparison of amplitude histogram and distributed models with the same parameters, it is been shown that hh polarization clutter is lognormal distribution, whereas vv polarization is k - distribution ; at the same time the correlation function and power spectrum density are been analyzed, at last the correlation compound k - distribution stochastic sequences whose covariance matrix is been given are been generated through sirp algorithm
文中先介紹了海雜波幅度的有關模型，通過對ipix雷達海雜波數據的i 、 q分量的直方圖以及傾斜度和峰度進行了分析和計算，證明了海雜波幅度不服從瑞利分佈;使用幅度直方圖和相同參數下的各種分佈模型進行比較，得出hh極化符合對數正態分佈，而vv極化服從k -分佈的結論;同時對海雜波的相關函數和功率譜進行了分析，最後使用sirp演算法產生了給定協方差矩陣的相關復合k -分佈隨機序列。In chapter 3 we analyze a useful statistical method - projection pursuit ( pp ), including its basic theory and application. we put out definitions of projection index and projection pursuit, then prove that pca is a special case of pp with sample variance as projection index and list some indices often used. in section 3. 3 we apply pp with information divergence index to hyperspectral image, and demonstrate the advanced ability of it by the comparison between it and pca
第三章圍繞一種新興的統計降維方法? ?投影尋蹤展開討論，概述投影尋蹤的一般理論，定義了投影指標和投影尋蹤的概念，證明了傳統的主成分分析方法是投影尋蹤的一個特例，證明了正態性與friedman指標為0的等價性；第三節針對高光譜圖像處理問題，從實例和理論兩個方面，論證了以信息散度為指標的投影尋蹤方法在提取信息的能力上優于以方差大小作為衡量信息量多少標準的主成分分析方法。Since the effects of turbulent atmosphere is prominent, this thesis concentrates on the effects of the turbulent atmosphere on the laser beam propagation in the atmosphere. the atmosphere refractive index model, especially refractive index fluctuation, power spectrum, phase spatial structure constant are introduced in the following and the specific structure function is achieved
根據大氣折射率模型，以及折射率起伏功率譜密度和相位空間結構常數，得到具體的結構函數；通過長程情況下的馬爾科夫近似，得到了互相關函數，對數振幅和相位協方差函數。Spca arithmetic has smaller number of spectral principal components and greater variance contribution than pca by choosing proper kernel functions and parameters
當選取合適的核函數和參數時，譜主成分的個數比主成分的個數要小且累積方差貢獻率要大。分享友人