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Design of an IF section for a Galactic Emission Mapping experiment

Miguel Bergano·Luis Cupido·Domingos Barbosa·Rui Fonseca·Dinis M. Santos·George Smoot
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Abstract

In the context of the Galactic Emission Mapping collaboration, a galactic survey at 5GHz is in preparation to properly characterize the galactic foreground to the Cosmic Microwave Background Radiation (CMBR). For the North sky survey, a new receiver is being developed. This 5GHz heterodyne polarimeter has a high gain IF (intermediate frequency) chain using the latest RF technology and microstrip design that we describe in the present article. Working at 600MHz central frequency, it consists of a pre-amplifier with an integral band-pass filter followed by an amplifier with digitally controlled gain and a frequency converter to zero-IF that feeds the ADC of a four channel digital correlator (outside the scope of the present article). This paper focuses the design options and constraints and presents the simulations and experimental results of a circuit prototype.

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Miguel Bergano, Luis Cupido, Domingos Barbosa, Rui Fonseca, Dinis M. Santos, George Smoot. 2007-02-23. Design of an IF section for a Galactic Emission Mapping experiment. https://arxiv.org/abs/astro-ph/0702629

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