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arXiv · 2101.06337

Design and implementation of a noise temperature measurement system for the Hydrogen Intensity and Real-time Analysis eXperiment (HIRAX)

Emily R. Kuhn·Benjamin R. B. Saliwanchik·Maile Harris·Moumita Aich·Kevin Bandura·Tzu-Ching Chang·H. Cynthia Chiang·Devin Crichton·Aaron Ewall-Wice·Austin A. Gumba·N. Gupta·Kabelo Calvin Kesebonye·Jean-Paul Kneib·Martin Kunz·Kavilan Moodley·Laura B. Newburgh·Viraj Nistane·Warren Naidoo·Deniz Ölçek·Jeffrey B. Peterson·Alexandre Refregier·Jonathan L. Sievers·Corrie Ungerer·Alireza Vafaei Sadr·Jacques van Dyk·Amanda Weltman·Dallas Wulf
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Abstract

This paper describes the design, implementation, and verification of a test-bed for determining the noise temperature of radio antennas operating between 400-800MHz. The requirements for this test-bed were driven by the HIRAX experiment, which uses antennas with embedded amplification, making system noise characterization difficult in the laboratory. The test-bed consists of two large cylindrical cavities, each containing radio-frequency (RF) absorber held at different temperatures (300K and 77K), allowing a measurement of system noise temperature through the well-known 'Y-factor' method. The apparatus has been constructed at Yale, and over the course of the past year has undergone detailed verification measurements. To date, three preliminary noise temperature measurement sets have been conducted using the system, putting us on track to make the first noise temperature measurements of the HIRAX feed and perform the first analysis of feed repeatability.

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Emily R. Kuhn, Benjamin R. B. Saliwanchik, Maile Harris, Moumita Aich, Kevin Bandura, Tzu-Ching Chang, H. Cynthia Chiang, Devin Crichton, Aaron Ewall-Wice, Austin A. Gumba, N. Gupta, Kabelo Calvin Kesebonye, Jean-Paul Kneib, Martin Kunz, Kavilan Moodley, Laura B. Newburgh, Viraj Nistane, Warren Naidoo, Deniz Ölçek, Jeffrey B. Peterson, Alexandre Refregier, Jonathan L. Sievers, Corrie Ungerer, Alireza Vafaei Sadr, Jacques van Dyk, Amanda Weltman, Dallas Wulf. 2021-01-16. Design and implementation of a noise temperature measurement system for the Hydrogen Intensity and Real-time Analysis eXperiment (HIRAX). https://doi.org/10.1117/12.2560270

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