Subjects: Astronomy >> Astrophysical processes submitted time 2022-11-17 Cooperative journals: 《天文研究与技术》
Abstract： Shadowing effects is one of the main consideration factors in designing complex system with multiple antennas. There will be 373 sets of antennas in Mingantu Station, after completing the construction of the program Meridian II equipment of National Major Science and Technology Infrastructure. Limited by test site, model complexity and computation, shadowing effect is usually hard to measure and to predict especially for electrically large-size structures. The observed solar radio data on S/C/X bands between 2017 and 2020 by MST (Mingantu Solar Radio Telescope), present the shadowing effect with the 20m antenna and remote hills as obstacles. The observed data with shadowing effect can be divided into antenna area, atmosphere area and hills area with different shadowing characteristics. Based on the prediction method of single knife-edge diffraction loss recommended by ITU-R P.526-15, a model of 20m antenna reflector is built, the shadowing effects on S/C/X-bands are simulated, and the results show agreement with those of observation. From simulation and observing results, shadowing effects are related with wavelength, obstacle character, distance and angle among obstacle, source and receiving antenna, the receiving antenna’s beam, and dynamic range of receiving system, etc.
Subjects: Astronomy >> Astrophysical processes submitted time 2019-05-07 Cooperative journals: 《天文研究与技术》
Abstract：射频干扰（Radio Frequency Interference, RFI）是射电天文观测设备无法回避的问题。国家天文台（内蒙古）明安图观测基地多台各具特色的射电观测设备、各类电磁辐射源及其传播路径共同组成了其复杂的电磁环境。现有超宽带高分辨太阳射电成像观测设备－明安图射电频谱日像仪，以及即将建设的子午二期工程的太阳行星际监测系统，包括米波-十米波射电日像仪、行星际闪烁望远镜和超宽带射电频谱仪等，全部频率覆盖1MHz－15GHz，观测结果用于太阳物理、空间天气监测和预报的关键问题研究，也对电磁环境提出了更高要求。介绍了明安图观测基地的观测设备及其地理环境，给出了方位频率功率谱、立体方向图、时间频率功率谱等展示的RFI初步监测结果，讨论RFI预防、消减及RFI自监测方案。
Subjects: Astronomy >> Astrophysical processes submitted time 2017-09-26 Cooperative journals: 《天文研究与技术》
Abstract：明安图射电频谱日像仪(Mingantu Ultrawide SpEctral Radioheliograph, MUSER)已经完成硬件建设，与之配套的数据处理系统也初步开发完成。为提高用户操作的可用性，简化操作难度，数据处理系统在提供传统的命令行用户界面的同时，也提供了网络交互方式。简单介绍了Web.py的基本概念和内部组件交互流程，讨论了基于Web.py进行网络开发的方法和流程，并利用 Web.py框架实现了数据处理系统的网络界面交互。成果已经应用，提高了日像仪数据处理系统的可用性，也为其它天文软件系统的开发提供了一定的借鉴与参考价值。
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