Radiometer equation for noise comparison radiometers

A complete radiometer equation is derived and used to develop better corrections and uncertainty estimates. I believe it to be the first thorough analysis of radiometers with unisolated front ends. We show that a corrected unisolated radiometer can have an accuracy similar to that of a well-isolated radiometer. The radiometer error is insignificant for radiometers with 40-dB isolation. However, for high-temperature applications (such as sources and standards above 3000 K), isolation is usually unnecessary