range vt. 1.排列;整理(頭發(fā)等)。 2.使歸類[班、行、隊];把…分類。 3.〔用被動形或反身形〕加入,站住…的一邊 ( with against)。 4.〔古、詩〕在…徘徊,在…走來走去,到處尋找;【航?!垦策?沿岸等)。 5.(用槍、望遠鏡等)對準(目標);瞄準;(炮術(shù))試(炮),試(射程)。 range books on a shelf 把書排列在書架上。 range the forest for game 在森林中跑來跑去獵取獵物。 be ranged according to size 按大小順序排列。 be ranged against 站在…的反對方向[…的一伙內(nèi)]。 range oneself 1. (放蕩后因結(jié)婚而)改過自新。 2. 得到固定職業(yè)。 range oneself on the side of 做…的伙伴。 range oneself with 做…的伙伴,與…做伙伴。 vi. 1.開列,進行;成直線 (with) (山脈等)相連,連綿;(動植物等)分布,蔓延,散布 (from... to) (子彈)能打到,達到。 2.加入,站在…的一邊 (with against) 與…為伍 (with)。 3.徘徊,走來走去,跋涉 (in over through) 【航?!垦埠健?4.(思想、研究等)到達,涉及。 5.【軍事】測距,試射測距;射程為。 6.(在某范圍內(nèi))變動,升降 (betweenfrom...to ...)。 range north and south 綿亙南北。 The gun ranges 3 miles. 這炮能打三英里遠。 The thermometer ranges from 45° to 50°. 溫度表的升降幅度是從45度到50度。 ranging fancy 動搖的愛情,水性楊花。 n. 1.(山脈、房屋等的)排列;連續(xù);綿亙。 2.(同種物的)一批,一套,一堆。 3.方向;范圍,區(qū)域;(動植物的)分布區(qū)域;生存期間;放牧區(qū)域,牧場;知識范圍;音域;幅度,差度;限度,極限;【數(shù)學】變程,量程;值域;全距。 4.作用[有效]半徑,距離;射程;靶子場,射擊場。 5.等級,類別,種類,部類。 6.徜徉,徘徊。 7.(能同時利用余熱燒水、烤面包的)多用鐵灶;火格子;梯級。 8.〔美國〕公地測量中相距六英里的兩子午線間的一排市鎮(zhèn)。 a range of buildings 一排房子。 the range of politics 政界。 a high [lower] range 大[小]比例,大[小]刻度。 the range of a thermometer 溫度表的(升降)幅度。 the range of one's voice 音域;聲音所能達到的范圍。 the effective range 有效射程。 foul the range finding (放煙幕)擾亂測距工作。 a projectile [proving, rocket] range 炮兵[軍用、火箭]靶場。 a range boss 〔美國〕(在某一地段內(nèi))看守放牧牲畜的人。 a range rider 〔美國〕牧童;山村看守人。 range cattle 放牧的牲畜。 a range forecast 【商業(yè)】(棉花的)收成估計。 a range of the cable 拋錨時所必需的一定長度的錨鏈。 an electronic range 電子爐。 a low range of prices 低檔價錢。 at long [short] range 在遠距離[近距離]。 go over the range 〔美國〕死。 in range with 和…開排著;和…同一方向。 in the range of 在…范圍內(nèi)。 out of one's range 能力達不到的;在知識以外的,不能辦到的。 out of [within] range 在射程外[內(nèi)]。 within the range of 在…的射程內(nèi),…能力達得到的,…所能的。
Second , it introduces an additive phase component which induces defocus in cross - range 二是引入了附加的相位分量,在方位向造成散焦。
So the match - filter function may be constituted to realize the cross - range compress 根據(jù)其調(diào)頻斜率,構(gòu)造方位向匹配濾波函數(shù)可實現(xiàn)方位向匹配壓縮。
Therefore , the compensation in range and cross - range towards the complex movement becomes a crucial step of isar imaging 對于目標的運動補償是isar成像中的關(guān)鍵技術(shù)。
The united signal for the isar signal processing is called the cross - range dimension signal . the cross - range dimension signal of the target with nearly tangent motion is a linear frequency modulated signal 由推導(dǎo)的準切向運動目標的方位向信號的相位表示式可以看出,此信號近似為線性調(diào)頻信號。
Isar transmits wide bandwidth signals to obtain high range resolution . the cross - range resolution is obtained by the doppler frequency information of the target ’ s rotation 逆合成孔徑雷達通過發(fā)射大帶寬信號獲得好的距離分辨率,利用目標相對于雷達的轉(zhuǎn)動產(chǎn)生多普勒頻率梯度來獲取好的方位向分辨力。
The former does not contribute to the imaging and is harmful . it influences isar imaging in two aspects : first , it causes the range misalignment of the range profiles which makes the processing in cross - range impossible 它對isar成像的影響有兩個方面:一是使相鄰的一維距離像在距離向錯開,無法進行方位向分辨。
They mainly work hard at softwares to accomplish special processing systems . the imaging quality has become better and better and now the range and cross - range resolution can be very high 系統(tǒng)設(shè)計者紛紛采用數(shù)字信號處理技術(shù),在軟件上多下功夫,做出專用處理設(shè)備,成像質(zhì)量不斷提高,其距離和方位向已達到了很高的分辨力。
Because of the limited cross - range resolution , high frequency ( hf ) over - the - horizon ( oth ) radar has the poor ability to determine the number of group targets and identify the large warship such as aircraft carrier in engineering applications 我國的高頻雷達已進入工程化應(yīng)用階段,但由于受分辨能力的限制,在群組目標的個數(shù)分辨及大型船只的識別等方面仍有不足之處。
To improve this ability , a higher cross - range resolution is needed . an inverse synthetic aperture radar ( isar ) achieves high resolution in the cross - range dimension by taking advantage of the motion between radar and targets to synthesize the effect of a larger antenna aperture 逆合成孔徑雷達( inversesyntheticapertureradar ,簡稱isar )信號處理對接收到的運動目標的回波信號進行相干處理,等價成一個大口徑天線,很大程度上提高了方位向距離分辨力。
Due to the short distance among the planes which fly in a group , the conventional low resolution radar can not distinguish them in both distance and azimuth ? if we use the technology of isar to resolve the difference among doppler frequency of the targets and obtain a fine resolution cross - cross image , we may separate them , but a long time of coherent processing is needed < , for the formation targets , it can be approximately divided to rigid body and nonrigid body , so for the formation targets , that can be regarded as rigid which has a relative position and an identical movement , can be approximately considered as a large target , and be compensated by translational phase with the rule of minimum entropy , but for the most those cannot accord with the approximation of rigid , being the doppler - frequency of the aim is linear changed , by the relax method with short data , increases the resolving performance of multiple target to the aim in the frequency domain , since cross - range resolution is based on the accumulative time , so it is greatly improve the resolution to formation targets by the instant cross - range image which produced by radon - wigner transformation 低分辨isan成像及干涉技術(shù)應(yīng)用研究一因此直接無法分辨編隊目標的架數(shù),我們借鑒isar的技術(shù),通過較長時間的相干積累,在多普勒頻域上對目標進行分辨。而對于編隊目標,可分為近似剛性的多目標和非剛性的多目標,所以對于可以近似為剛體的編隊目標相對位置固定,運動方式一致,可以近似看作一個大目標,采用最小墑準則對平動相位的進行補償,但是大多數(shù)并不滿足剛體近似的編隊目標,由于目標在相干積累時間的多普勒頻率近似呈線性變化,通過對較短數(shù)據(jù)利用relax的時頻分析方法,提高了頻率域上目標分辨的性能。由于橫向分辨率取塊于橫向積累時間,所以利用radnwigner變換得到瞬時的一維橫向距離像大大提高了對編隊目標的分辨,對仿真和實測數(shù)據(jù)的大量分析結(jié)果表明此方法的有效性和可行。