Very low-noise differential radiometer at 30 GHz for the PLANCK LFI

• Published in: IEEE transactions on microwave theory and techniques Vol. 53; no. 6; pp. 2050 - 2062
• Main Authors: Aja, B., Artal, E., de la Fuente, L., Pascual, J.P., Mediavilla, A., Roddis, N., Kettle, D., Winder, W.F., Cara, L.Pi, de Paco, P.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2005; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Assembly; Circuit properties; Cosmic microwave background; Cosmic microwave background (CMB); cryogenic; Cryogenics; Electric, optical and optoelectronic circuits; Electronics; European Space Agency; Exact sciences and technology; Finite element method; Instruments; low-noise amplifier (LNA); Mathematical models; Microwave antenna arrays; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; microwave radiometer; Microwave radiometry; Microwaves; Modules; Noise temperature; Observatories; PLANCK low-frequency instrument (LFI); Radiometers; Space missions; Temperature; Testing; Testing, measurement, noise and reliability; Wideband; Cosmic microwave background (CMB); System architecture; Low noise circuit; Microwave radiometer; Cosmic background radiation; Differential circuit; System design; PLANCK low-frequency instrument (LFI); Cryogenic circuit; low-noise amplifier (LNA); Measuring system; cryogenic; Performance analysis
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/TMTT.2005.848815

The PLANCK mission of the European Space Agency is devoted to produce sky maps of the cosmic microwave background radiation. The low-frequency instrument is a wide-band cryogenic microwave radiometer array operating at 30, 44, and 70 GHz. The design, test techniques, and performance of the complete differential radiometer at 30 GHz are presented. This elegant breadboard 30-GHz radiometer is composed of a front-end module (FEM) assembled at the Jodrell Bank Observatory, Cheshire, U.K., and a back-end module assembled at the Universidad de Cantabria, Cantabria, Spain, and Telecomunicacio/spl acute/, Universitat Polite/spl acute/cnica de Catalunya, Barcelona, Spain. The system noise temperature was excellent, mainly due to the very low noise performance of the FEM amplifiers, which achieved an average noise temperature of 9.4 K.