Advanced pseudo-correlation radiometers for the Planck-LFI instrument

A. Mennella; M. Bersanelli; R. C. Butler; D. Maino; N. Mandolesi; G. Morgante; L. Valenziano; F. Villa; T. Gaier; M. Seiffert; S. Levin; C. Lawrence; P. Meinhold; P. Lubin; J. Tuovinen; J. Varis; T. Karttaavi; N. Hughes; P. Jukkala; P. Sjman; P. Kangaslahti; N. Roddis; D. Kettle; F. Winder; E. Blackhurst; R. Davis; A. Wilkinson; C. Castelli; B. Aja; E. Artal; L. de la Fuente; A. Mediavilla; J. P. Pascual; J. Gallegos; E. Martinez-Gonzalez; P. de Paco; L. Pradell

arXiv · astro-ph/0307116

Advanced pseudo-correlation radiometers for the Planck-LFI instrument

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Abstract

The LFI (Low Frequency Instrument) on board the ESA Planck satellite is constituted by an array of radiometric detectors actively cooled at 20 K in the 30-70 GHz frequency range in the focal plane of the Planck telescope. In this paper we present an overview of the LFI instrument, with a particular focus on the radiometer design. The adopted pseudo-correlation scheme uses a software balancing technique (with a tunable parameter called gain modulation factor) which is effective in reducing the radiometer susceptibility to amplifier instabilities also in presence of small non-idealities in the radiometric chain components, provided that the gain modulation factor is estimated with an accuracy of the order of 0.2%. These results have been recently confirmed by experimental laboratory measurements conducted on the LFI prototype radiometers at 30, 70 and 100 GHz.

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A. Mennella, M. Bersanelli, R. C. Butler, D. Maino, N. Mandolesi, G. Morgante, L. Valenziano, F. Villa, T. Gaier, M. Seiffert, S. Levin, C. Lawrence, P. Meinhold, P. Lubin, J. Tuovinen, J. Varis, T. Karttaavi, N. Hughes, P. Jukkala, P. Sjman, P. Kangaslahti, N. Roddis, D. Kettle, F. Winder, E. Blackhurst, R. Davis, A. Wilkinson, C. Castelli, B. Aja, E. Artal, L. de la Fuente, A. Mediavilla, J. P. Pascual, J. Gallegos, E. Martinez-Gonzalez, P. de Paco, L. Pradell. 2003-07-07. Advanced pseudo-correlation radiometers for the Planck-LFI instrument. https://arxiv.org/abs/astro-ph/0307116

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