Broadband acoustooptic spectrometer used as backend for remote sensing of trace gases in the atmosphere

摘要

A broad-band acoustooptical spectrometer was used as a backend of a millimeter wave heterodyne receiver to detect the rotational transition of ozone at 142.175 GHz. The AOS has a total bandwidth of 1.07 GHz covered with 1728 channels with 1.2 MHz resolution bandwidth each. The influence of the instrumental filter characteristic, linearity in power, stability in power and frequency, to the measurements and subsequent retrieval of atmospheric ozone profiles have been analyzed. Estimation of a linear slope and an offset brightness temperature has been included in the inversion process using the optimal estimation method.