Development work of a 119 GHz compact antenna test range (CATR), based on a 2.4 m 2.0 m hologram and its application on the Odin telescope tests are described. The hologram element comprises seven parts, which are fabricated using silk-screen printing techniques. Comparison between the theoretical and the measured quiet-zone fields of the hologram CATR is made, which demonstrates the correctness of the analysis method and also the importance of high quality physical joints between the hologram parts. The CATR has been successfully used in the measurement of a 1.1-m offset reflector antenna onboard the Odin spacecraft. The measured and calculated antenna radiation patterns are in good agreement in the main beam region. The effects of the imperfections in the quiet-zone field and in the aperture field of the antenna on the measurement results are simulated.Index Terms-Holographic interferometry, millimeter wave antennas, radio astronomy, submillimeter wave antennas.

An 89 GHz waveguide coupled direct detector based on a low-barrier Schottky diode is presented. The main focus is to reduce white and 1/f noise to achieve high signal-to-noise ratio values above 35 dB. The design also addresses the Schottky barrier height deviation over temperature and its compensation within the RF circuit. The fabricated detector is characterised and compared with simulation results, proving a high accuracy level of the design and fabrication process, as well as good knowledge of the applied Schottky diode. The results prove the suitability of the detector to be considered for the second European meteorological operational satellite programme (MetOp-SG).

ESA's Soil Moisture and Ocean Salinity (SMOS) mission was launched 2 Nov 2009 and, to date, is still in good health, providing valuable L-band observations of the Earth surface [1]. A number of products are obtained from these, including thin sea ice [2], frost/thaw soils [3], high winds [4], ocean surface wind [5] and Sun brightness temperature [6], besides the main mission measurements of soil moisture and sea surface salinity [7][8]. This paper deals with the description and early results of some technology activities conducted by ESA applying the lessons learnt by SMOS and in preparation of an advanced L-band radiometer mission.

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