A 110 GHz ozone radiometer with a cryogenically cooled planar Schottky mixer

A total power radiometer for monitoring the stratospheric ozone spectral line at 110 GHz is presented. Special features such as a cooled planar Schottky mixer as the front end and efficient reduction of standing waves in the quasi-optics are discussed in detail. The noise temperature of the receiver is 500 K (single sideband), and the total bandwidth of the receiver is 1 GHz. A dual acoustooptical spectrometer is used for the signal detection.<>