Limb sounding radiometers determine the concentrations of atmospheric constituents by measuring thermal emission from the atmospheric limb along a tangent path. A number of critical technologies are needed to build a microwave limb sounding radiometer. The basic components include optics, mixers, local oscillators, IF amplifiers and spectrometers. Designs for all these components exist, but further development would improve performance particularly at frequencies of a few hundred gigahertz and above. The most critical item is the mixer. With no RF amplification, the dominant source of receiver noise is from this device. Mixer noise temperatures are listed together with the radiometer noise temperatures after making allowance for pre-mixer losses and IF amplifier noise.
|Title of host publication||Proceedings of SPIE - The International Society for Optical Engineering|
|Number of pages||3|
|Publication status||Published - 1993|
|Event||Proceedings of the 18th International Conference on Infrared and Millimeter Waves - Colchester, Engl|
Duration: 6 Sep 1993 → 10 Sep 1993
|Conference||Proceedings of the 18th International Conference on Infrared and Millimeter Waves|
|Period||6/09/93 → 10/09/93|