空军预警学院学报
空軍預警學院學報
공군예경학원학보
Journal of Air Force Radar Academy
2013年
3期
206-208
,共3页
相干斑%随机噪声SAR%线性调频SAR%幅度图像
相榦斑%隨機譟聲SAR%線性調頻SAR%幅度圖像
상간반%수궤조성SAR%선성조빈SAR%폭도도상
speckle%random noise SAR%linear frequency modulation SAR%amplitude image
针对不同信号对相干斑的影响,探讨了随机噪声(RN)SAR的相干斑。由于随机噪声信号的非周期性,从物理角度解释了随机噪声SAR的相干斑弱于通常的线性调频信号SAR的相干斑,然后利用拖尾Rayleigh分布,采用标准差和等效视数(ENL)指标对两幅SAR幅度图像的相干斑进行了评价。通过对同一场景的随机噪声SAR幅度图像和线性调频SAR幅度图像相干斑进行仿真分析,结果表明随机噪声SAR的相干斑弱于线性调频SAR的相干斑。
針對不同信號對相榦斑的影響,探討瞭隨機譟聲(RN)SAR的相榦斑。由于隨機譟聲信號的非週期性,從物理角度解釋瞭隨機譟聲SAR的相榦斑弱于通常的線性調頻信號SAR的相榦斑,然後利用拖尾Rayleigh分佈,採用標準差和等效視數(ENL)指標對兩幅SAR幅度圖像的相榦斑進行瞭評價。通過對同一場景的隨機譟聲SAR幅度圖像和線性調頻SAR幅度圖像相榦斑進行倣真分析,結果錶明隨機譟聲SAR的相榦斑弱于線性調頻SAR的相榦斑。
침대불동신호대상간반적영향,탐토료수궤조성(RN)SAR적상간반。유우수궤조성신호적비주기성,종물리각도해석료수궤조성SAR적상간반약우통상적선성조빈신호SAR적상간반,연후이용타미Rayleigh분포,채용표준차화등효시수(ENL)지표대량폭SAR폭도도상적상간반진행료평개。통과대동일장경적수궤조성SAR폭도도상화선성조빈SAR폭도도상상간반진행방진분석,결과표명수궤조성SAR적상간반약우선성조빈SAR적상간반。
Aimed at the impacts of various signals on speckles, the speckles of random noise SAR are studied in this paper. In view of non-periodicity of random noise signals, it is cleared that the speckles of random noise SAR are less than those of the common linear FM signal SAR in terms of physics, and then, by taking advantages of tailing Rayleigh distribution, the speckles of two SAR amplitude images are assessed by means of standard deviation and ENL indexes, and finally, the speckle analysis of random noise SAR amplitude image and linear FM SAR amplitude image in the same scene, by using the test data. Experimental results show that the speckles of random noise SAR are really weak, compared with those of linear FM SAR.