目標反射波 的英文怎麼說
中文拼音 [mùbiāofǎnshèbō]
目標反射波
英文
target return- 目 : Ⅰ名詞1 (眼睛) eye 2 (大項中再分的小項) item 3 [生物學] (把同一綱的生物按彼此相似的特徵分為幾...
- 標 : Ⅰ名詞1 [書面語] (樹梢) treetop; the tip of a tree2 (枝節或表面) symptom; outside appearance; ...
- 反 : Ⅰ名詞1 (方向相背) reverse side 2 (造反) rebellion 3 (指反革命、反動派) counterrevolutionari...
- 射 : Ⅰ動詞1 (用推力或彈力送出) shoot; fire 2 (液體受到壓力迅速擠出) discharge in a jet 3 (放出) ...
- 波 : Ⅰ名詞1 (波浪) wave 2 [物理學] (振動傳播的過程) wave 3 (意外變化) an unexpected turn of even...
- 目標 : 1. (對象) target; objective 2. (目的) goal; aim; destination
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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。Exposure ratios between spectral bands are determined from in situ reflectance spectra of objects in scene.
光譜波段之間的曝光量比值,可以根據景物中目標的就地測定的反射光譜確定。The major job is manufactured a transmitter, which has three upmixer channels. its function is to up convert the signals from c - band to ka - band. the input local oscillator is provided by a low frequency crystal oscillator which has a good performance of phase noise, through 512 times multiply to ka band. this sysetem is used in the laboratory as transmitter source of the fuze, for the multidimensional objects in practise, which lead to the complexity of the reflect signal, so the amplitude, frequency and the phase of the transmit signals both have a key role in dealing with the reflection signals. therefore, this system requires for both the coherence of the single channel ’ s amplitude, phase and multi channels
本文的主要工作是應用戶要求製作一具有三發射通道的上變頻系統,可以將c波段的微波信號上變頻到ka波段的毫米波信號。系統的本振輸入基頻由一相位噪聲非常好的低頻率晶振提供,經過512次的倍頻放大至ka波段。本系統作為實驗室中引信的發射源,由於目標反射信號具有時變的多維性,反射信號變得極為復雜,在信號處理時,不僅信號幅值、頻率有決定意義而且相位關系也很有決定意義。In this paper, the target radiate characteristics and waveband selection of the infrared system reviewed briefly ; the suppression of the stray radiation in the infrared sub - system is discussed ; the material selection, the support structure and optimization of the primary mirror in the infrared sub - system of the theodolite, every factor which will affect the surface figure of the mirror is discussed in detail and get the result that in the circumstance of shooting range, the primary factor which affects the surface figure of the mirror in the infrared sub - system is temperature changing, this ca n be resolved by using material of low expansion coefficient and using same material in the mirror and the mirror seat
本文將對紅外系統的目標輻射特徵分析和波段選擇進行簡要回顧,討論紅外系統中雜散輻射的抑制,並詳盡分析經緯儀紅外光學系統設計中所涉及到的反射鏡的材料、支撐、結構和優化設計等問題,認真討論和分析影響主鏡的面形精度的各種可能因素。並指出:在靶場環境下影響經緯儀紅外分系統主鏡面形精度的主要原因是溫度的變化,這種情況可通過選擇低線膨脹系數的材料並且使鏡座和反射鏡採用相同的材料予以解決。Depending on the nature of the reflecting objects, the intensity of the reflected beam will vary.
隨著反射目標的性質不同,反射回來的波束強度也就不同。Beam riding systems use a target tracker whose purpose is to maintain the antenna boresight pointing at the centre of the reflecting area of the target.
波束制導系統使用一個目標跟蹤裝置,它的目的是保持天線視軸指向目標反射的中心。The mine - hunting sonar system is produced in such a condition, and it defines the torpedo ' s position by use of sound wave emit by the sonar array which is installed on the bottom of the ship
獵雷聲納就是在這樣的情況下誕生的。它是利用安裝在船底部聲納基陣腔內的聲納發射的聲波,經目標反射后成像在顯示屏上,從而確定水雷的存在及位置。The second part brings forward a new ar - model - based arm detection method based on features of arm and characteristics of velocity and acceleration of the radar echoes. by establishing two - order ar models, this new detection method computes the poles of models representing different targets, thus estimates the acceleration of the targets so as to determine the nature of the targets. furthermore, this method can not only be applied when the arm is being tracked by radar, but also be put into use in radar ’ s seeking and scanning times
第二部分則是根據反輻射導彈( arm )的特點及其雷達回波信號中速度、加速度等特徵,提出了一種新的基於ar模型的arm檢測演算法,該方法通過建立二階ar模型、估計代表不同目標的模型極點,並由此估算目標加速度來判斷目標性質,該方法不僅可以在雷達已跟蹤上arm后採用,而且適用於雷達搜索掃描時使用,模擬結果表明該方法具有解析度高,對雷達脈沖重復頻率( pulserepetitionfrequency , prf )及積累脈沖數要求不高的特點,在低的prf及少的積累脈沖下,利用該方法仍可有效地識別檢測arm 。At this moment, both the direct signal and the reflected one impinge into the array, and make the amplitude and phase of the echo change, which cannot be separated from the direct one, thus cause server errors of elevation ’ s estimation, even the failure of tracking
此時直達信號與反射信號同時進入天線,造成回波幅度與相位的變化,並且這種變化不能從直達信號中分離出來,從而造成目標仰角估計的嚴重誤差,甚至引起跟蹤的失效。The land clutter is useless signals for target detection caused by land terrain. the multipath effect is some kind of interference which is caused by wave reflection on terrain. the diffraction effect is the phenomenon of wave propagation into shadow region
地雜波是由地面散射引起的對目標探測無用的信號;多路徑是由電磁波在地面反射所引起的干涉;衍射則是電波繞射傳播到遮蔽區的現象。From this method we can obtain a better signal to clutter ratio, and improve the resolution, so we can position the target accurately
對實際探測數據的分析表明,這種方法不僅可有效的抑制雜波,還可獲得目標反射時間的準確信息,為進一步確定目標深度提供條件。The polarimetric information in the target scattering signal has great potential on target detection, enhancement, filtering and recognition. some novel techniques can be proffered for detecting concealed targets, weakening the influences of adverse em environments, confronting active jamming and recognizing targets. basic theory of radar polarization is studied firstly
雷達目標散射信號中的極化信息在目標檢測、增強、濾波及識別中有著巨大的應用潛力,為雷達系統在反隱身、削弱惡劣電磁環境的影響、對抗有源干擾和識別目標等方面提供了新的技術途徑。This paper presents a method that uses many independent backscattering units to replace the whole object, which reflects the geological characteristics of objects on ground to some extent. 2
在對回波信號的模擬中本文提出了將目標表面分成許多獨立散射單元來代替整個面目標的實現方法,在一定程度上反映了地物目標的幾何特性。In this paper applications of wavelet packet analysis, higher order cumulant method and some image processing method in the processing of gpr data acquired from subsurface target backscattering are presented, which includes the following contents : methods to denoise and suppress background clutter for target detection ; to improve the time resolution for target position ; target recognition
本文討論了小波包分析、高階累積量分析及圖象處理方法在沖擊脈沖探地雷達淺層反射信號處理中的若干應用,包括對目標去噪、確定目標時間位置及進行目標識別方法的研究。The main works and results are as follows : 1. by use of one order multiple scattering theory, light scattering and reflection by a single coating layer is analyzed. the variance of radiation intensity, bidirectional reflection distribution function ( brdf ) and laser radar scattering cross section with coating layer parameters is given, with the effect of rough contrast on bidirectional reflection distribution function
本文主要研究了單層和多層塗層結構介質的光散射特性,以及近場條件下復雜目標對激光波束的散射,其主要工作如下: 1 、採用一階多重散射近似理論分析單層塗層對光波的散射和反射,計算並討論了輻射強度、雙向反射分佈函數和單位面積激光雷達散射截面隨塗層結構參數的變化規律,數值分析了粗糙基底對雙向反射分佈函數的影響。分享友人