AVTIS - a dual-mode imaging millimetre wave radar/radiometer for volcanological surveying

We present the design and preliminary results for an advanced mm-wave remote sensing instrument. AVTIS (AH Weather Volcano Topography Imaging Sensor) is a dual-mode passive imager and active radar operating at 94 GHz, designed to yield topographic and thermal maps of volcanic lava domes. The mechanically scanned imager uses a 0.5m Cassegrain antenna mounted on a pan & tilt gimbal. The radiometer is of the total power heterodyne type, and the radar operates in an FMCW mode. When images are collected from multiple viewpoints, it will be possible to construct a thermo-spatial 3D map of the lava dome. The project volcanologists will use this data to enhance the modeling of the growth and collapse mechanisms in lava domes, which may ultimately lead to improved hazard warning.