Astronomy and Computing?(?IF?1.927?)?Pub Date?:?2022-03-23?, DOI:?10.1016/j.ascom.2022.100568
Y. Wang, Z. Zhang, H. Zhang, W. Zhu, D. Li, P. Wang
射頻干擾（Radio Frequency Interference，RFI）是目前高靈敏度射電望遠(yuǎn)鏡面臨的普遍問題，隨著其他人造無線電業(yè)務(wù)的發(fā)展，該問題越來越嚴(yán)重?？臻g過濾技術(shù)是由 Kocz 等人開發(fā)的。（2010b）從多波束接收器獲取的數(shù)據(jù)中濾除常見的 RFI。在本文中，我們描述了一種基于空間濾波的 RFI 緩解管道，該管道采用非對稱重加權(quán)懲罰最小二乘平滑 (ArPLS) 算法 (Baek et al., 2015)，并將其應(yīng)用于使用 500 米孔徑球形采集的數(shù)據(jù)射電望遠(yuǎn)鏡 (FAST) 19 光束接收器。首先，我們使用 ArPLS 從每個光束的輸入數(shù)據(jù)中估計和移除基線。其次，我們用 RFI 投影矩陣構(gòu)造空間濾波器。第三，我們用優(yōu)化的閾值標(biāo)記受污染的數(shù)據(jù)。最后，將結(jié)果封裝在一個掩碼文件中，這是一種用于 RFI 掩碼的格式磷R乙小號噸○. PSR J0528+2200 的數(shù)據(jù)證實了我們方法的有效性。Radio Frequency Interference (RFI) is currently a common problem faced by radio telescopes with high sensitivity, and it is getting worse with the development of other man-made radio services. Spatial filtering techniques are developed by Kocz et al. (2010b) to filter out the common RFI from the data taken by a multi-beam receiver. In this paper, we describe a spatial filtering based RFI mitigation pipeline with the Asymmetrically reweighted Penalized Least Squares smoothing (ArPLS) algorithm (Baek et al., 2015), and apply it to the data taken with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) 19-beam receiver. Firstly, we use ArPLS to estimate and remove the baseline from the input data for each beam. Secondly, we construct the spatial filter with the RFI projection matrices. Thirdly, we flag the contaminated data with an optimized threshold. In the end, the results are encapsulated in a mask file, a format for RFI masks in?PRESTO. The effectiveness of our method has been confirmed by the PSR J0528+2200’s data. Our method outperforms?rfifind?on true positive rate, it also supports parallelization and GPU acceleration. Our method is used to mitigate RFI in some FAST pulsar survey programs.
