A broadband reflectometer based on high speed IMPATT oscillators has been developed. The reflectometer is capable of sweeping a bandwidth of 26.5-110 GHz in a time of 1.25mS. The operating frequency range is divided into five subbands. Each subband has an associated polarizer and custom broadband antenna. The description of one subband is detailed in Figure 1.
D. R. Vizard, D. R. Vizard,
"High speed millimetre wave reflectometry", Proc. SPIE 1576, 16th International Conference on Infrared and Millimeter Waves, 15765I (1 October 1991); doi: 10.1117/12.2297911; https://doi.org/10.1117/12.2297911