西安电子科技大学学报(自然科学版)
西安電子科技大學學報(自然科學版)
서안전자과기대학학보(자연과학판)
JOURNAL OF XIDIAN UNIVERSITY(NATURAL SCIENCE)
2015年
2期
28-34
,共7页
邵鹏%邢孟道%李学仕%李亚超
邵鵬%邢孟道%李學仕%李亞超
소붕%형맹도%리학사%리아초
步进频信号%大斜视%频域带宽合成%相位跃变%斜距误差
步進頻信號%大斜視%頻域帶寬閤成%相位躍變%斜距誤差
보진빈신호%대사시%빈역대관합성%상위약변%사거오차
stepped frequency signal%high squinted%frequency bandwidth synthetic%phase discontinuity%slant-range error
针对步进频信号带宽合成存在相位跃变的问题,提出一种新的频域带宽合成方法。由于雷达与目标相对运动是导致合成频谱相位跃变的主要原因,因此,该方法根据雷达与目标相对运动的斜距形式对各个子脉冲引入的相位误差进行补偿。文中采用了改进的步进频数据处理方法,首先对子频带进行脉冲压缩,然后进行带宽合成、二次距离压缩及徙动校正,从而避免了子频带进行徙动校正后对带宽合成的影响。在完成带宽合成后,采用调频变标(Chirp Scaling,CS)算法得到了斜视二维高分辨合成孔径雷达(Synthetic Aperture Radar,SAR)图像。为了证明该方法的有效性,给出了仿真及实测数据的处理结果。由理论仿真与实测数据的对比分析可知,该方法有效地实现了窄带步进频信号合成宽带信号。
針對步進頻信號帶寬閤成存在相位躍變的問題,提齣一種新的頻域帶寬閤成方法。由于雷達與目標相對運動是導緻閤成頻譜相位躍變的主要原因,因此,該方法根據雷達與目標相對運動的斜距形式對各箇子脈遲引入的相位誤差進行補償。文中採用瞭改進的步進頻數據處理方法,首先對子頻帶進行脈遲壓縮,然後進行帶寬閤成、二次距離壓縮及徙動校正,從而避免瞭子頻帶進行徙動校正後對帶寬閤成的影響。在完成帶寬閤成後,採用調頻變標(Chirp Scaling,CS)算法得到瞭斜視二維高分辨閤成孔徑雷達(Synthetic Aperture Radar,SAR)圖像。為瞭證明該方法的有效性,給齣瞭倣真及實測數據的處理結果。由理論倣真與實測數據的對比分析可知,該方法有效地實現瞭窄帶步進頻信號閤成寬帶信號。
침대보진빈신호대관합성존재상위약변적문제,제출일충신적빈역대관합성방법。유우뢰체여목표상대운동시도치합성빈보상위약변적주요원인,인차,해방법근거뢰체여목표상대운동적사거형식대각개자맥충인입적상위오차진행보상。문중채용료개진적보진빈수거처리방법,수선대자빈대진행맥충압축,연후진행대관합성、이차거리압축급사동교정,종이피면료자빈대진행사동교정후대대관합성적영향。재완성대관합성후,채용조빈변표(Chirp Scaling,CS)산법득도료사시이유고분변합성공경뢰체(Synthetic Aperture Radar,SAR)도상。위료증명해방법적유효성,급출료방진급실측수거적처리결과。유이론방진여실측수거적대비분석가지,해방법유효지실현료착대보진빈신호합성관대신호。
Due to the problem of high grating-lobe caused by phase discontinuity for frequency bandwidth synthetic,a new method of frequency synthetic bandwidth is proposed.The cause for phase discontinuity of frequency spectrum is the relative motion between radar and scatterers.The phase error for every sub-pulse according to different forms of the slant range between radar and scatterers is compensated by this method. A new approach is put forward for step frequency signal processing after the frequency band is synthesized. First,the pulse is compressed and frequency band is synthesized.After the frequency band is synthesized, the second range compression and the range migration correction are implemented. Then, phase discontinuity due to the corrected range migration correction is avoided.Finally,Chirp Scaling is applied to obtain the squint two-dimension high resolution SAR(Synthetic Aperture Radar,SAR)image.In order to identify the availability of this method,simulation results are shown in the paper.Experiments on raw data and simulation show that the wide-band signal could be synthesized by the narrow-band stepped signal.