Millimeter wave detection of mesospheric ozone using a high resolution chirp transform spectrometer backend

The diurnal variation of mesospheric ozone can be measured by groundbased millimeter wave radiometry. Due to the narrow linewidth of the millimeter wave emissions of ozone from the upper mesosphere not only a low noise radiometer frontend, but also a high resolution spectrometer backend is required. Since end of 1992 the authors are monitoring the 142 GHz ozone line using a chirp transform spectrometer (CTS) backend. During this time they made the experience that the CTS is a very reliable and accurate instrument and they obtained a data set of high quality. An instrument description is given and spectra of mesospheric ozone are presented