Airborne Radar ELDORA/ASTRAIA

The ELDORA (Electra Doppler Radar) / ASTRAIA (Analyse Stereoscopique par Radar Aeroporte Sur Electra) is an X-band (9.3–9.8 GHz) dual-beam airborne Doppler radar, jointly developed by the National Center for Atmospheric Research (Boulder, USA) and the French Centre National de la Recherche Scientifique (CNRS) in Paris. Designed for high-resolution measurements of air motion and rainfall characteristics in large or remote storms, it employs a fore-aft scanning technique with two independent radar systems to collect dual Doppler information in flight. This enables the generation of two-dimensional wind fields from observation surfaces passing through storms, utilizing a complex transmitted waveform with four distinct frequencies and a peak power of 35–40 kW. The system features two 35 kW traveling wave tube amplifiers driven by a common synthesizer, with transmitted signals passing through a dual-channel rotary joint to separate fore and aft antennas mounted in a rotodome, which spin at 20–40 rpm to provide the necessary scanning motion.

radartutorial.eu: https://www.radartutorial.eu/19.kartei/08.airborne/karte009.en.html