Improved multi-beam unit layout and orthomode transducers for FAST
YU Jinglong1,2, LIU Hongfei1,2, GAN Hengqian1, CAO Yang1
1. National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100101, China; 2. University of Chinese Academy of Sciences, Beijing 100049, China
Abstract：Five-hundred-meter aperture spherical radio telescope (FAST) is a multi-disciplinary basic research platform that is used for a wide range of astronomy research. The L band 19 beam receiver is mainly used for large sky surveys and pulsar searches. The receiver plays an important role in the discovery of new pulsars and the study of fast radio burst (FRB). The design of the multi-beam feed front-end was analyzed to improve the multi-beam feed system layout and the orthogonal mode coupler. This paper describes the improvements and the corresponding test results. These design methods provide design and technical guidelines for the design and upgrading of large aperture antenna feed systems.
于京龙, 刘鸿飞, 甘恒谦, 曹洋. FAST多波束单元布局及正交模耦合器改进设计[J]. 清华大学学报（自然科学版）, 2022, 62(11): 1803-1808.
YU Jinglong, LIU Hongfei, GAN Hengqian, CAO Yang. Improved multi-beam unit layout and orthomode transducers for FAST. Journal of Tsinghua University(Science and Technology), 2022, 62(11): 1803-1808.
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2022, Vol. 62 
