用带有平滑约束的CLEAN算法恢复日像仪图像

Heliography Image Reconstruction Using Smooth CLEAN Algorithm

为了解决CLEAN算法处理展源时存在的迭代抖动、收敛不稳定的弊端,借鉴最大熵算法的平滑约束概念,通过修正CLEAN算法迭代过程中的脏束,提出了带有平滑约束的CLEAN算法。通过对国家天文台拟建日像仪图像恢复仿真,验证了该改进算法在图像恢复质量和分辨率两个方面的性能均较CLEAN算法有所提高。

CLEAN algorithm has the limitation of iterative dithering and convergence instability when it was applied to extend sources processing. Inspired by the ability of Maximum Entropy Method to proceed the extend sources, the paper proposed a CLEAN algorithm with smooth constraint by modifying the dirty beam. Finally the simulation was conducted of radio heliography solar image reconstruction in China National Astronomical Observatories. Results show superiority of the improved algorithm in both image quality and resolution.