Full coverage millimetre wave primary noise standards for 18-170 GHz

Conventional noise diode transfer standards used in the calibration of sensitive radiometers and other low noise components or instruments can produce large errors due to limitations of frequency coverage and absolute accuracy. The Cryogenic Noise Calibration Standard described features interchangeable waveguide based horn antennas allowing full frequency coverage from 18-170 GHz and beyond. The state-of-art design of the vessel and its temperature profile allows the effects of stray radiation to be controlled within the required accuracy specifications.