A 75-110 GHz millimeter-wave spectrometer for pollution studies

A multisensor approach is being developed at the University of Texas at Arlington (UTA) to improve upon current capabilities in environmental monitoring. The sensors consist of an FIR for operation in the near to thermal infrared regions of the spectrum, a long-path UV (LPUV) spectrometer, and an active/passive millimeter-wave (MMW) spectrometer that will operate over the 75-110 GHz (W-band) atmospheric window. There are advantages and disadvantages to using each of these three spectral regions and it appears that better qualification and quantification of pollutants can be achieved by a combined use of these instruments. This is discussed briefly. During 1993 the authors presented the unique features in the preliminary design for the MMW instrument. It is now being tested in the laboratory and in mid-1994 outdoor testing is scheduled to begin. Shortly thereafter instrument performance testing at selected pollution sites is planned, when it is used in conjunction with the FTIR and LPUV. This paper discusses the final instrument design, and results of laboratory and field tests.<<ETX>>