A Novel Imaging Method Based on Reweighted Total Variation for an Interferometer Array on Lunar Orbit  

作　　者：Xiaocheng Yang Mengna Wang Lin Wu Jingye Yan Junbao Zheng Li Deng 

机构地区：[1]School of Computer Science and Technology,Zhejiang Sci-Tech University,Hangzhou 310018,China [2]Sate Key Laboratory of Space Weather,Chinese Academy of Sciences,Beijing 100190,China [3]National Space Science Center,Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Research in Astronomy and Astrophysics》2023年第12期204-214,共11页天文和天体物理学研究（英文版）

基　　金：supported by the Specialized Research Fund for State Key Laboratories under Grant 202217;the Key Laboratory of Solar Activity and Space Weather(NSSC)under Grant E26600021S。

摘　　要：Ground-based radio observations below 30 MHz are susceptible to the ionosphere of the Earth and the radio frequency interference.Compared with other space mission concepts,making low frequency observations using an interferometer array on lunar orbit is one of the most feasible ones due to a number of technical and economic advantages.Different from traditional interferometer arrays,the interferometer array on lunar orbit faces some complications such as the three-dimensional distribution of baselines and the changing sky blockage by the Moon.Although the brute-force method based on the linear mapping relationship between the visibilities and the sky temperature can produce satisfactory results in general,there are still large residual errors on account of the loss of the edge information.To obtain the full-sky maps with higher accuracy,in this paper we propose a novel imaging method based on reweighted total variation(RTV)for a lunar orbit interferometer array.Meanwhile,a split Bregman iteration method is introduced to optimize the proposed RTV model so as to decrease the computation time.The simulation results show that,compared with the traditional brute-force method,the RTV regularization method can effectively reduce the reconstruction errors and obtain more accurate sky maps,which proves the effectiveness of the proposed method.

关 键 词：methods data analysis-instrumentation interferometers-techniques interferometric-space vehicles instruments-(cosmology:)dark ages-reionization-first stars 

分 类 号：P184.5[天文地球—天文学]