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Hybrid-panel-based new design idea for large reflector antenna

Science China(Technological Sciences) 2023年第1期66卷 115-126页

作者： LIAN PeiYuan YAN YueFei WANG CongSi QIN Long XUE Song WANG Na XU Qian ZHAO WuLin ZHENG YuanPeng School of Mechano-Electronic Engineering Xidian UniversityXi'an 710071China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 8300llChina China Electronics Technology Group Corporation No.39 Research Institute Xi'an 710065China China Electronics Technology Group Corporation No.54 Research Institute Shijiazhuang 050081China

Large reflector antennas are widely used as radio telescopes and active main reflectors are generally applied to improve the surface accuracy. Considering that the high cost has been one important problem in engineering, it is worth discussing whether it is necessary to install actuators on all the panels. Thus, in this paper, a hybrid-panel-based new design idea for large reflector antenna is proposed. Assuming that the actuators are installed only in the region of the reflector with large deformations and there are no actuators in other region to reduce the actuator number, the surface accuracies and the corresponding electromagnetic(EM) performances calculated by three different panel adjustment strategies are compared. The most effective method is that the deformed reflector should be first preadjusted to reduce the gravity deformation and then the panels equipped with actuators should be adjusted to the locations determined by the best fitting reflector(BFR) derived by the deformed reflector with no actuators. A 35 m reflector antenna is adopted as an example to calculate the surface accuracy and EM performance when parts of the panels are equipped with actuators. The simulation results show that there is no need to install actuators on all panels and the presented method can greatly reduce the number of actuators with guaranteed surface accuracy. Thus, during the antenna structural design phase, once the surface accuracy requirement is given, the number of actuators can be minimized to reduce the manufacturing and maintenance costs as much as possible. This paper can provide valuable guidance for the design of an active main reflector with hybrid panels.

关键词： reflector antenna hybrid panel actuator distribution adjustment strategy surface accuracy power pattern

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Far-Field pattern Tolerance Analysis of Reflector Antenna with Random or System Error Based on Interval Arithmetic

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Chinese Journal of Electronics 2018年第3期27卷 641-647页

作者： LI Peng LI Na XU Wanye WANG Wei Key Laboratory of Electronic Equipment Structure Design Ministry of Education Xidian University

A novel analytic approach for the research of effect on electromagnetic performance of reflector antennas with deformation, including random processing error and system error caused by external loads(such as wind,gravity, and solar radiation), in panels of the reflector surface is proposed. The deformations are modeled as error intervals, and their impact on the electromagnetic performance, including radiation power pattern and some main electromagnetic characteristics(such as side lobe level,peak power, and half-power beamwidth), are efficiently estimated by Interval analysis(IA). The closed-form equations indicate the relationship between the error interval and the bounds(upper and lower bounds) of the radiated power pattern interval by exploiting the rules of interval arithmetic. Two kinds of surface errors(random and system error) and two shapes of deformation area(bump-like and sector) are taken into account in the numerical examples to assess the validation and effectiveness of the proposed approach. The results of the examples show that the proposed IA-based approach has great capability and effectiveness regarding the traditional statistical method(such as Monte-Carlo method).

关键词： Reflector antenna Interval analysis Random error System error power pattern

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中东权力格局转换对阿以和平进程的影响

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国际政治 2010年第5期

作者：赵葆珉

冷战结束后，以色列维持了在中东政治和阿以和平进程中的强势地位，这种地位是冷战后美国在中东独霸地位的单极格局所决定的。全球金融危机的蔓延与伊拉克和阿富汗问题久拖不决消耗了美国霸权赖以生存的硬实力与软实力，奥巴马政府不得... 详细信息

冷战结束后，以色列维持了在中东政治和阿以和平进程中的强势地位，这种地位是冷战后美国在中东独霸地位的单极格局所决定的。全球金融危机的蔓延与伊拉克和阿富汗问题久拖不决消耗了美国霸权赖以生存的硬实力与软实力，奥巴马政府不得不调整政策，转而在阿以之间寻求更加平衡的中东政策，以色列自“9·11”以来的战略优势期恐将终结。随着中东格局由美国单极独霸格局向美、欧、俄、中、印以及伊朗、以色列、沙特、埃及、土耳其等地区大国构成的多元权力格局的演化，政治优势开始向阿拉伯—伊斯兰世界倾斜。在此背景下，以色列、巴勒斯坦和其他阿拉伯国家需转换安全观念，争取在联合国决议的基础上以更加积极的姿态参与阿以和平进程，实现中东持久和平。

关键词：中东和平进程权力格局美国中东政策阿以关系 Middle East Peace Process power pattern US Middle East Policy Arab-Israeli Relations

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