Remote microwave wavelength spectrometry using an infrared fibre optic telecommunication network Original Research Article

Reported is the first experimental demonstration of remote microwave spectroscopy of an absorbing gas over a fibre optic link [J.F. Alder, J.G. Baker, Quantitive Millimetre Wavelength Spectrometry, Royal Society of Chemistry, Cambridge, 2002]. Using a high speed telecommunication network and a 12 GHz YIG source, a microwave modulated infrared carrier has been transmitted down 1 km of optical fibre. Absorption lines as weak as 2.83×10−5 m−1 have been observed by coupling the recovered microwave signal through a 2 m Stark modulated absorption cell.