Title of Paper: HAMSR - The High Altitude MMIC Sounding Radiometer


Principal Author: Mr. Bjorn Lambrigtsen


Abstract: The High Altitude MMIC Sounding Radiometer (HAMSR), recently developed under ESTO sponsorship, represents the next generation of microwave atmospheric sounders. It is the world’s first sounder to use Monolithic Microwave Integrated Circuit (MMIC) receivers and incorporates other miniature solid state components as well. HAMSR is therefore lightweight, compact and sensitive. It combines, in a single package, functionality previously requiring several separate instruments, and provides temperature, humidity and cloud liquid water sounding, with a common field of view. It also implements dual-band temperature sounding, which makes it possible to determine scattering and estimate rain rates – important for investigation of storms and severe weather. Due to miniaturization it can be accommodated on even small platforms, such as pilot-less aircraft. HAMSR is intended to demonstrate and validate the new technology and other advanced design concepts as well as to support scientific missions, such as field experiments and satellite validation campaigns. It has been selected for participation in the August-September 2001 CAMEX-4 field campaign, which is part of a multi-agency effort to investigate hurricanes and the "land-fall" problem. On that mission HAMSR will be flown on the NASA ER-2 high altitude aircraft and will provide fundamental atmospheric parameters to CAMEX science investigators. HAMSR is essentially an implementation of the microwave segment of IMAS, a proposed next-generation infrared-microwave sounding system, and uses technology and components developed under that program. The HAMSR measurement characteristics are very similar to those of ATMS, a next-generation satellite microwave sounder also derived from IMAS and currently under development. HAMSR is therefore well suited as a technology testbed and validation system for ATMS as well as similar future developments.