Quasi-optical sensors for investigation of acousto-electromagnetic phenomena of Popocatepetl volcano

This article focuses on meteorological electronics based on the space resea rch of acoustic-electromagnetic phenomena caused by Popocatepetl volcano (M exico). The main purpose is to present two different types of quasi-optical sensors, one of them is formed by a modulator based on a surface oriented p,i,n structure with "deep" junctions; and by a silicon detector (avalanche photodiode with separated regions of absorption and multiplication: APDSAM ). This system guarantee both good sensibility and wide range of sensing, s ub-millimeter and millimeter range, This sensor has the advantage that can be realized as a planar array. On the other hand, for the remote measuremen t of basic meteorological parameters and chemical state by means of radiobr ightness temperatures (radiometer systems) a low noise receiver on the base of dielectric waveguide and Schottky diodes cooled by means of cryoelectro nic element is used.