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arXiv · 1708.08521

The cloverleaf antenna: A compact wide-bandwidth dual-polarization feed for CHIME

Meiling Deng·Duncan Campbell-Wilson
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Abstract

We have developed a compact, wide-bandwidth, dual-polarization cloverleaf-shaped antenna to feed the CHIME radio telescope. The antenna has been tuned using CST to have smaller than -10dB s11 for over an octave of bandwidth, covering the full CHIME band from 400MHz to 800MHz and this performance has been confirmed by measurement. The antennas are made of conventional low loss circuit boards and can be mass produced economically, which is important because CHIME requires 1280 feeds. They are compact enough to be placed 30cm apart in a linear array at any azimuthal rotation.

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Meiling Deng, Duncan Campbell-Wilson. 2017-08-28. The cloverleaf antenna: A compact wide-bandwidth dual-polarization feed for CHIME. https://doi.org/10.1109/antem.2014.6887670

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