海陆交界非平稳场景星载ScanSAR扇贝效应抑制方法

扫描式合成孔径雷达(ScanSAR)因不受光线、天气影响,能够提供宽测绘带图像而被广泛应用在海洋监测领域。但ScanSAR图像的扇贝效应(Scalloping)和子带拼接效应(Inter-Scan Banding,ISB)严重地降低图像质量,尤其在海陆相接一类的非平稳场景下,干扰更为严重,影响图像的应用效能。针对上述问题,文章给出了一种基于图像分层和卡尔曼滤波的ScanSAR图像扇贝效应和子带拼接效应的抑制方法。针对非平稳场景,先进行图像分层处理使其满足线性卡尔曼滤波需求;然后,利用加性二维周期函数对子图层的扇贝效应和子带拼接效应进行建模;再将卡尔曼滤波器应用于条纹抑制;最后,对真实ScanSAR图像数据的有效处理结果验证了算法的有效性。

Suppression of Scalloping Effects in Spaceborne ScanSAR Images for Non-Stationary Scene of Coastal Area Monitoring

Scan synthetic aperture radar (ScanSAR) cannot be affected by weather or light, so it is widely used in maritimemonitoring and detection. However, the scalloping and inter-scan banding (ISB) are two effects of ScanSAR images whichseriously degrade the picture quality. Some non-stationary scenery such as coastal area can further increase the difficultyof ScanSAR image post-processing. In this paper, an algorithm was proposed to suppress scalloping and ISB in ScanSARimages by image segmentation and Kalman filter. Based on ScanSAR working model and mechanism of scalloping, firstlythe scalloping and ISB were regarded as an additive two-dimensional periodic function, and then the noise stripes weresuppressed by Kalman filter. For the non-stationary scene, image segmentation was applied to make the picture satisfy theKalman filtering requirement. Finally, the validity of the algorithm was verified by the results obtained after processing re.al ScanSAR image data.