The cloud and precipitation airborne radiometer - Populating the international sub-millimetre airborne radiometer

An upgrade funded by the European Space Agency to the Met Office ISMAR instrument as a risk reduction for potential future spaceborne radiometers is described. This adds four channels between 118GHz and 664GHz, to measure cloud, precipitation, and cirrus cloud. The receivers are all heterodyne based, with multiplied local oscillators and sub-harmonic mixers. The manufacturing of the receivers is underway and testing of the overall channels is starting. This will be followed by integration of all the channels onto ISMAR. The integrated instrument is to have its test flight on the FAAM aircraft in November 2012 and the project is to conclude in early 2013.