NTT in Japan is working to develop stand-off Gas detection using
a transceiver based upon SIS power detectors and source
generation by optical down conversion.
Dr Shimizu-san, who leads the development group, has recently
taken delivery of a broadband 220 to >500 GHz Multiplexer and
high gain (64dBi antenna feed)
The beam profiles at 7.5 Metres well match the simple Gaussian
Beam-Mode predictions, as can be seen below. The predicted
beamwidth value at this distance is some 155mm, compared
with the displayed measurement of 15 cm.