Geographical Reference Correction of MTVZA-GYa Microwave Scanner/Probe Operating on Meteor-M No. 2-3 Satellite

Abstract—This paper is focused on georeferencing measurements of the MTVZA-GYa Russian scanner/probe installed on board the Meteor-M no. 2-3 spacecraft. The instrument was put into operation in August 2023 and continues operating normally. The failure of the satellite’s centimeter communication line in October 2023 has significantly reduced the coverage area of MTVZA-GYa measurements. Currently, they are limited to the line of sight of the satellite by ground receiving stations. The absence of all-season clear boundaries of the sea surface/land transition in the observation area makes it impossible to estimate the quality and adjust the georeferencing of MTVZA-GYa measurements. In this regard, in the presented study, the measurement data with global coverage accumulated by the instrument in August–September 2023 have been analyzed. Based on the positive experience of working with previous versions of MTVZA instruments, similar methods for assessing the quality of georeferencing and searching for angles that correct it have been used. At the same time, the existing design differences of the considered instrument (change in the scanning direction and change in the operating observation sectors) have required some adjustments to the georeferencing implementation algorithm. Studies have shown that the optical axes of the device corresponding to individual groups of frequency channels have different orientations. In this regard, the search for angles that correct the georeferencing has been performed for each group separately. When applying a differentiated approach to georeferencing different groups of frequency channels using the values of the correcting angles of roll, pitch, and yaw, we have managed to achieve the following accuracy indicators: (4.59 ± 8.22) km for the 10.6–23.8 GHz channel group, (5.51 ± 8.83) km for the 31.5–48.0 GHz channel group, and (8.03 ± 11.69) km for the 52–91.65 GHz channel group.