Learn More
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(More)
We present the current status of the QUIJOTE (Q-U-I JOint TEnerife) CMB Experiment, a new instrument which will start operations early 2009 at Teide Observatory, with the aim of characterizing the polarization of the CMB and other processes of galactic and extragalactic emission in the frequency range 10-30 GHz and at large angular scales. QUIJOTE will be a(More)
A GaN high electron mobility transistor technology with a gate length of 0.25 μm has been used to design and fabricate a cascode broadband low noise amplifier (LNA). The two-stage monolithic microwave integrated circuit (MMIC) with feedback topology yields a bandwidth of 0.5-3 GHz at a constant gain of 35 dB and noise figures of less than 1.5 dB. A(More)
The stability of microwave amplifiers is normally analysed as a two port network. An amplifier has at least a third port for biasing that might be considered for stability. Bias line impedances can lead to oscillations in amplifiers. Full stability analysis of a millimetre wave MMIC amplifier has been carried out using a three port scattering parameter(More)
An investigation of metamorphic high electron mobility transistor stability at cryogenic temperature is presented in this paper. Unlike in the case of two-finger transistors, the measurements of cooled four-finger devices with large gate widths exhibit unstable behavior in the form of steps in the current-voltage characteristics, discontinuities in the(More)
The design of a broad-band monolithic cryogenic low-noise amplifier (MMIC LNA) in the Q band, aimed to be used in radio-astronomy receiver front-end modules is presented. A 70 nm gate-length GaAs mHEMT process from OMMIC foundry is used to manufacture the amplifier. An accurate model for the minimum noise bias point of the transistor has been obtained at(More)
We present low-noise amplifiers (LNA) that have been developed in the framework of two pre-qualification ESA projects for frequencies between 54 and 229 GHz for the METOP-SG satellite program. The main goal of these satellites is to provide data for operational weather forecast and climate change. Specifically temperature and water vapor measurements can be(More)
This paper presents preliminary polarization measurements and systematic-error characterization of the Thirty Gigahertz Instrument receiver developed for the QUIJOTE experiment. The instrument has been designed to measure the polarization of Cosmic Microwave Background radiation from the sky, obtaining the Q, U, and I Stokes parameters of the incoming(More)
Modern communication and radar systems show an increasing demand for robust ultra-broadband amplifiers for low-noise applications. A set of three different 0.5 GHz to 20 GHz MMIC LNAs using a GaN HEMT technology with a gate length of 0.25 μm was designed and fabricated, each with a noise figure between 3 dB and 7 dB over frequency. Two designs with(More)