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arXiv · 1107.1157

W-band prototype of platelet feed-horn array for CMB polarisation measurements

Francesco Del Torto·Marco Bersanelli·Francesco Cavaliere·Adriano De Rosa·Ocleto D'Arcangelo·Cristian Franceschet·Massimo Gervasi·Aniello Mennella·Enrico Pagana·Alessandro Simonetto·Andrea Tartari·Fabrizio Villa·Mario Zannoni
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Abstract

We present the design and performance of a 2x2 prototype array of corrugated feed-horns in W-band. The module is fabricated using a so-called "platelet" technique by milling Aluminum plates. This technique is suitable for low-cost and scalable high performance applications. Room temperature Return Loss measurements show a low (<-30 dB) reflection over a 30% bandwidth with a maximum matching of -42 dB at 100 GHz for all four antennas. Beam pattern measurements indicate good repeatability and a low (-25 dB) sidelobe and crosspolarisation levels. This work is particularly relevant for future Cosmic Microwave Background polarisation measurements, which require large microwave cryogenic detector arrays coupled to high performance corrugated feed horns.

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Francesco Del Torto, Marco Bersanelli, Francesco Cavaliere, Adriano De Rosa, Ocleto D'Arcangelo, Cristian Franceschet, Massimo Gervasi, Aniello Mennella, Enrico Pagana, Alessandro Simonetto, Andrea Tartari, Fabrizio Villa, Mario Zannoni. 2011-07-06. W-band prototype of platelet feed-horn array for CMB polarisation measurements. https://doi.org/10.1088/1748-0221/6/06/p06009

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