測頻擴展法 的英文怎麼說
中文拼音 [cèbīnkuòzhǎnfǎ]
測頻擴展法
英文
frequency range expanding method-
Backed up by the soplat theory based on particle kinematics, the second chapter of this paper presents with analysis and simulation of several single observer passive measurement models, which uses such relative movement parameters as bearings changing rates and centrifugal acceleration information on the basis of bearings measurements. in the third chapter, the observability of location respectively using bearings and its changing rates information and centrifugal acceleration information is analyzed, and its observable condition is got. the fourth chapter puts forward the modified covariance extended kalman filtering ( mvekf ) against the defect of traditional extended kalman filtering ( ekf ), whose performance is simultaneously compared in the chapter with the performance of ususal tracking algorithm such as ekf, mgekf, iekf by computer simulation
在近年來提出的基於質點運動學原理的單站無源定位理論基礎上，本文第二章提出了幾種在角度測量的基礎上增加角度變化率及相對運動的離心加速度等運動學參數的單站無源測量模型，並對它們進行了分析和模擬；第三章分別對利用角度及其變化率信息定位和利用離心加速度信息定位的可觀測性進行分析並得到了相應的可觀測條件；第四章針對傳統擴展卡爾曼（ ekf ）方法的缺點，提出了一種修正協方差的擴展卡爾曼濾波（ mvefk ）方法，並將其和ekf 、 mgekf 、 iekf等常用的單站無源定位濾波方法進行了性能模擬比較；第五章通過引入雷達機動目標跟蹤方法和模型，提出了利用角度及其變化率對機動輻射源跟蹤的多級噪聲自適應方法和imm方法；第六章主要對角度變化率和離心加速度參數的獲取技術進行了研究，提出了幾種高精度測量脈沖序列多普勒頻率變化率的方法。According to the guidline, two nd : yag lasers have been designed and set up, one is end - pumped by lower output power ld using a selfoc micro lens, and the other is end - pumped by high output power ld using a pair of lenses are designed, and the characteristics such as output power and power stabilization of both solid - state lasers are investigated. thirdly, when an empty liquid crystal cell is inserted in the cavity of the nd : yag laser pumped by high power ld, the laser can operates in single axial mode. finally, according to the relationship between the laser output power and the longnitudinal a ld - end - pumped nd : yag laser sensor for displacement measurement has been investigated theoretically and demonstrated experimently, the results indicate that when the mean radius of pumping inside the laser cavity is far less than that of the oscilating laser mode, the exponential of the output power is a gauss function of the longitudinal positon of focused spot of ld pumping beam, both the measurement range and the sensitivity are dependent on the incident pumping power, as the incident pumping power is increased, the measurement range is enlarged and the sensitivity is improve d
本文首先介紹了ld泵浦nd ： yag激光器的發展狀況、主要特性及其應用，從四能級速率方程出發，推導了ld泵浦nd ： yag激光器的閾值、輸出功率和斜效率的表達式，並簡述了激光器的工作原理、結構型式和倍頻方法；其次，以空間相關的速率方程為基礎，提出了ld端面泵浦nd ： yag激光器的設計方法，給出了一定泵浦耦合方式下，振蕩光模尺寸、最佳輸出耦合率、泵浦光模尺寸、泵浦光焦斑位置等參數的選取依據，以此為依據，設計了自聚焦透鏡耦合小功率ld泵浦nd ： yag激光器和透鏡組耦合高功率ld泵浦nd ： yag激光器，對激光器的輸出功率和功率穩定性等特性進行了實驗研究；再次，在帶尾纖輸出的高功率ld泵浦nd ： yag激光腔內插入一隻空液晶盒，觀察到了激光器以單縱模運轉；最後，根據泵浦光焦斑端面位置對激光輸出功率的影響規律，提出了ld端面泵浦nd ： yag激光位移傳感新方法，並進行了理論和實驗研究，研究結果表明：當激光晶體內泵浦光平均光斑半徑遠小於振西安理工大學碩士學位論文蕩光束腰半徑時，激光輸出功率的自然指數與泵浦光焦斑的縱向位置成高斯變化規律，測量范圍和靈敏度依賴于泵浦功率，隨著泵浦功率的增加，測量范圍擴大，靈敏度提高，當端面泵浦功率為7 . 24w （最大輸出功率為1 . 926w ）時，激光位移傳感器的測量范圍和靈敏度分別是13 . 045mm和0 . 148mw / pm 。The author accomplished this dissertation through taking part in the project. the main contents of this dissertation are : based on the national capacitance standard, the principle and the measurement method for capacitance metrology are studied, and the frequency response of a four - terminal - pair ( 4tp ) capacitor acted as the capacitance standard is measured in the extended frequency range
本文研究的主要內容是:在國家「電容基準」的基礎上，選用四端對電容器作為標準器，研究電容量值擴展頻段的計量原理及方法，測定其頻率響應，建立國家的擴展頻段電容標準;以擴展頻段的電容標準為量值標準，進行測量四端對電阻器和校準單埠電容器頻率響應的研究。In the text, direct sequence spread spectrum signal ( dsss signal ) is the main object, and some nonlinear methods based on chaotic theory, used in the prediction of signal and detection of signal is studied
本文以保密通信中廣泛使用的直接序列擴展頻譜信號（ dsss信號）為主要對象，研究了一些基於混沌理論的非線性的方法在信號預測和信號檢測中的應用。Thirdly, a modified extended chirp scaling ( ecs ) algorithm is presented, which solves the problem of producding fine focused images in the class of chirp scaling ( cs ) algorithm. lt can be used for uwb - sar imaging effectively. the phas e error produced by cs operation are analyzed. a windowed process in two dimension frequency domain before cs operation are proposed. it can improve the quality of image and widen the effectively swath and increase the peak to sidelobe ratio ( pslr )
然後針對chirpscaling （ cs ）類演算法不能對參考點精確聚焦的問題，提出了一種改進的擴展cs （ ecs ）演算法，實現了對uwb - sar的高效成像；分析了cs操作產生的相位誤差，提出在cs操作之前在二維頻率域對信號加窗，除有效提高信號的峰值旁瓣比（ pslr ）外，還可以提高圖像質量，增加有效測繪帶寬度。( 2 ) because of t he variability of rock subjected to outside action, three new conceptions : postive damage basic damage and negative damage, are suggested, which can deal with the condition that rock density became large. ( 3 ) the present damage variables based on ct number mostly include ct average number of the rock without damage, which is difficult to measure, so a new damage variable, which includes the average ct number is proposed, on the other hand, strain equal theory is generalized because the one put foreword by lemaitre is not good enough to use. ( 4 ) a axial damage constitutive equation is proposed and testified. ( 5 ) with the circle times, the damage propagation laws of two different rocks, subjected to circle of freezing and thawing, are studied, and in the analysis process, traditional analysis method including average ct number and is used, some important conclusions are reached : inner damage of soft rock containing a large mount of apertures is largely propagating with the time increasement of circle, however, at the preliminary time, the hard rock containing a small mount of aperture is a little propagating, at late time, the influence become large ; ( 6 ) zone separation and statistics frequency put forward is used to analysized the three different damage propagation in the open circumstance, when they are subjected to the different circle times of freezing and thawing, in which the temperature variability is linear, different freezing rate, and different freezing temperature, and no water is supplied during the test
在研究過程中本文主要做了以下工作： （ 1 ）針對巖石損傷變化較小時，運用ct均值和方差分析不方便的缺陷，本文提出運用對ct數范圍劃分區段的方法，根據各區段統計頻率的變化規律來分析損傷擴展狀況； （ 2 ）針對巖石受到外部作用的多變性，本文提出了基準損傷，正損傷，負損傷的概念，在某種程度上考慮了巖石受到外部作用時的壓密情況； （ 3 ）現有的基於ct數的損傷變量大多需要用到巖石基體的ct均值，這實際上是很難觀測到的，因此本文建議了一個可運用巖石初始狀態ct均值的損傷變量，由於現有的勒邁特教授應變等價原理使用上的不便，本文在其基礎上進行了推廣； （ 4 ）建議了一個可用巖石初始狀態ct數和彈性模量的單軸損傷本構方程，並用算例進行了驗證； （ 5 ）對兩種不同巖石在開放環境下受到凍融循環作用且融化過程中補水時，內部損傷隨凍融循環次數增加的擴展規律進行了探討，主要運用了常規的ct均值和ct方差的分析方法進行分析，試驗發現：對于孔隙率和含水率較高，密度和強度較低的軟弱巖石，凍融循環次數對損傷結構的擴展有明顯的影響，而對于孔隙率和含水率較低，密度和強度較高的硬巖，凍融循環次數對其損傷結構擴展初期由於含水率低的原因，影響不是太大，而後期由於水補給后，含水率較高的原因，凍融影響逐漸增大； （ 6 ）運用了本文提出的區段劃分和統計頻率的方法，深入地分析了開放環境下的線性溫度變化的凍融循環次數，凍結溫度，凍結速度不同巖石作用時，其內部損傷隨凍融循環次數，凍結速度和凍結溫度變化的擴展規律，需要指出的是除了在試驗前飽水外，凍融過程中沒有補水。Firstly, according to the characteristic that the doppler frequency shift signal can be approximated as a single sinusoid signal, the extended sinusoid signal retrieval ( pisarenko and esprit ) methods are presented and signal state and measurement formulations are developed, so the kalman filter recursive method is got. the brief introduction of low velocity moving target doppler frequency shift signal wigner - ville transformation and wavelet transformation expression are presented in this paper. secondly, because the clutter is gaussian distribution, cumement and high - order spectrum based methods are presented and the simulation results prove their good performance to suppress gaussian clutter in low velocity moving target doppler frequency shift signal processing
一個方面是根據低速目標的多普勒信號可簡化為單一正弦波形式這一特點，得到了擴展的高斯色噪聲背景下的諧波恢復演算法，即高斯色噪聲中的pisarenko諧波恢復法和旋轉因子不變法（ esprit ） ；並推導了信號的狀態方程和觀測方程，進而得到基於卡爾曼濾波的遞推演算法對信號進行提取；本文還簡單的介紹了低速運動目標的多普勒頻移信號的wigner - ville變換與小波變換；另一個方面是針對雜波服從高斯分佈這一特點，提出了對接收信號求累積量和高階譜來對高斯雜波進行抑制。Since the energy of 18 - information track signal is concentrated around upper frequency and lower frequency, the frequency of the modulation signal is low, and it must have high resolution, we use zfft to detect it. as the energy of um - 71 signal is more concentrated, we use extreme value method to detect the frequency of modulation signal in frequency domain, which can satisfy the frequency resolution
針對18信息軌道信號能量集中在上、下邊頻附近且低頻信息頻率低的情況，提出了用zoom - fft （ zoom指頻率擴展或細化，簡稱zfft ）演算法進行信號的局部放大檢測低頻信息，以提高信號的頻率解析度，而um - 71軌道信號能量集中在載頻附近，在頻域上採用極值法檢測低頻信息，即可滿足信號頻率解析度的要求。The emphasis is on improving the method of intrusion detection and the negative selection algorithm. the primary works of the dissertation are as follows : ( 1 ) the statistical data indicates that there are high - frequency connections in lan, and these connections is sparse. based on the statistical data and its characters, the method of the negative detection is improved
本文在研究hofmeyr提出的基於免疫原理的分散式網路入侵檢測模型的基礎上，對其檢測方法和否定選擇演算法在實際應用中存在的局限性進行了詳細分析，並作了有益擴展和改進，主要工作如下： （ 1 ）在局域網中，使用統計分析的方法，得出了存在高頻連接的結論；利用這一結論及高頻連接的特點對該模型中的檢測方法進行了改進。Following is specific work : a novel algorithm for fractal video sequence coding based on the extended quadtree video partition with the circular prediction mapping and the noncontractive mapping is proposed
提出了在擴展的四叉樹視頻壓縮的基礎上，利用環形預測映射和幀間非壓縮映射相結合的視頻序列分形編碼方法。In this paper, the control system of rectifying strip steel deviation based on ppf control algorithm is designed, and a way of detecting the deviation signal of strip steel is introduced, which adopted redundancy control that involves capacitance sensor and highfrequency photoelectricity sensor, and improved reliability of the system. the system includes : siemens s7 200 programmabled logic controller, em235 analog signal module expanded, td200 for manipulating and displaying
本文設計了基於ppf控制演算法的帶鋼糾偏控制系統，並提出採用電容傳感器與高頻光電傳感器冗餘檢測帶鋼偏移信號的方法，增加了系統的可靠性。系統採用siemenss7 - 200plc控制，擴展了em235模擬模塊， td200用於操作及顯示。It follows that the description of characteristics of g programming language in labview and the process of building virtual instruments. the paper provides a new spectrum analyzing method of the combination of spread spectrum with fft. at last it gives the arithmetic realization and programming diagram of every part of spectrum monitoring and signal searching
介紹了labview下如何通過計算機介面獲取數據的過程，數據採集過程中各個參數的演算法選擇；同時闡述了labview平臺下g語言的特點及構建虛擬儀器的過程，然後介紹了信號分析處理部分採用的頻率擴展與fft相結合的頻域分析方法；頻譜監測部分各個模塊的演算法實現；最後給出了信號搜索部分的演算法實現及其原理框圖。According to the review and comparison of today ' s adsl test instruments, the author finds the lack of the traditional test methods and indicates that easy to use, versatility and extensible are crucial aspects to design an adsl test instruments. the author also bring up a new method, the adaptive test method which can be used to test the adsl ' s transmission characters on the whole band dynamically
通過對國內外現有adsl檢測設備的特點進行總結和比較之後，找出了傳統測試方法的不足之處，指出易用性、通用性和可擴展性是設計adsl測試儀表的關鍵，提出了新的adsl線路傳輸特性的檢測方案? ?使用自適應演算法實現對adsl整個頻段的衰減情況動態測量，並且在matlab上進行了模擬。分享友人