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arXiv · 1502.02735

A Compact Filter-Bank Waveguide Spectrometer for Millimeter Wavelengths

Sean Bryan·George Che·Christopher Groppi·Philip Mauskopf·Matthew Underhill
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Abstract

We present the design and measurements of a 90GHz prototype of a millimeter-wave channelizing spectrometer realized in rectangular waveguide for astronomical instrumentation. The device was fabricated using conventional high-precision metal machining, and the spectrometer can be tiled into a 2D array to fill the focal plane of a telescope. Measurements of the fabricated five-channel device matched well with electromagnetic simulations using HFSS and a cascaded S-matrix approach. This motivated the design of a 54-channel R=200 spectrometer that fills the single-moded passband of rectangular waveguide in the 130-175 GHz and 190-250 GHz atmospheric windows for millimeter-wave spectroscopic mapping and multi-object spectroscopy.

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Sean Bryan, George Che, Christopher Groppi, Philip Mauskopf, Matthew Underhill. 2015-02-09. A Compact Filter-Bank Waveguide Spectrometer for Millimeter Wavelengths. https://doi.org/10.1109/tthz.2015.2433919

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