Development of wideband orthomode transducers for FAST cryogenic receiver system
Journal article, 2020

This paper describes the design, construction, and performance of the wideband orthomode transducers (OMTs) for the L- (1.2-1.8 GHz), the S- (2-3 GHz) and the P- (0.56-1.12 GHz) band receiver systems of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). These OMTs operate at the cryogenic temperature of 70K to reduce their thermal noise contribution to the receiver chains. The development on the FAST L- and S-band quad-ridged waveguide (QRWG) OMTs is carried out based on the theoretical mode analysis. In view of the miniaturization of FAST cryogenic receiver system at P-band, a novel wideband compact bowtie dipole OMT is designed with an octave bandwidth as well as a length of only quarter wavelength. The proposed L-, S- and P-band OMTs are designed and optimized by using Ansys High Frequency Structure Simulator (HFSS), and then manufactured, tested at room temperature. Measurement of FAST cryogenic receiver system noise is also performed with the L-, S- and P-band OMTs installed. The measured results fully comply with the design specifications.

instruments

telescopes

FAST

Author

Jin Fan

Chinese Academy of Sciences

Kai Zhu

Chinese Academy of Sciences

Heng-Qian Gan

Chinese Academy of Sciences

Peng Jiang

Chinese Academy of Sciences

Jian Yang

Chalmers, Electrical Engineering, Communication, Antennas and Optical Networks

Yang Cao

Chinese Academy of Sciences

Hong-Fei Liu

Chinese Academy of Sciences

Hang Zhang

Chinese Academy of Sciences

Ming-Lei Guo

Chinese Academy of Sciences

Xiang-Wei Shi

Chinese Academy of Sciences

Research in Astronomy and Astrophysics

1674-4527 (ISSN)

Vol. 20 5 071

Subject Categories

Astronomy, Astrophysics and Cosmology

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1088/1674-4527/20/5/71

More information

Latest update

8/19/2020