Above 110 GHz, antenna scalar measurements have been performed using mm-wave sources, such as a Gunn oscillator, a Gunn followed by a Schottky-diode harmonic generator, a BWO or a carcinotron
, and video or bolometric detection.
In the UK, which had already provided the microwave industry with the cavity magnetron, Austrian emigre Rudolf Kompfner had stumbled on the travelling wave tube (TWT), while a French team under Oskar Doehler produced the first carcinotron
, opening the way to effective deception and barrage jamming techniques, respectively.
They would anticipate radar to survive next year's plasma noise sources even as it has CW magnetrons, carcinotrons
, TWT repeaters, light-weight chaff, absorbent materials and so on.