Millimetre-wave measurement radars for 140 and 280 GHz

Radio modelling is used to carry out scaled radar trials under repeatable, controlled conditions. Such trials can provide a thorough knowledge of the radar scattering characteristics of a particular target by the use of precision metalized models which are made to a scale of typically 1/16 full size. The model is viewed by a measurement radar radiating at a frequency 16 times that of the comparable full-scale radar. Much of the modelling work is aimed at the development of mathematical models for which the individual echo sources must be determined first by measurements. The 'specification' for coherent measurement radars is discussed, and the block schematic of the 'coherent' radar is presented. The 140 GHz radar considered comprises a modulator trolley and an aerial trolley which houses the microwave head and receiver. The most of the 280 GHz radar is mounted in a large cabinet with the transmitter source, a 280 GHz carcinotron, in the lower half.