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arXiv · astro-ph/0509671

A broadband FFT spectrometer for radio and millimeter astronomy

Arnold O. Benz·Paolo C. Grigis·V. Hungerbuhler·Hansueli Meyer·Cristian Monstein·Bruno Stuber·D. Zardet
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Abstract

The core architecture, tests in the lab and first results of a Fast Fourier Transform (FFT) spectrometer are described. It is based on a commercially available fast digital sampler (AC240) with an on-board Field Programmable Gate Array (FPGA). The spectrometer works continuously and has a remarkable total bandwidth of 1 GHz, resolved into 16384 channels. The data is sampled with 8 bits, yielding a dynamic range of 48 dB. An Allan time of more than 2000 s and an SFDR of 37 dB were measured. First light observations with the KOSMA telescope show a perfect spectrum without internal or external spurious signals.

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Arnold O. Benz, Paolo C. Grigis, V. Hungerbuhler, Hansueli Meyer, Cristian Monstein, Bruno Stuber, D. Zardet. 2005-09-22. A broadband FFT spectrometer for radio and millimeter astronomy. https://doi.org/10.1051/0004-6361%3A20053568

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