On the Possibility of Failure Indication in the Operation of MTVZA-Series Russian Scanners–Probers Based on Georeferencing Quality Analysis

Abstract—In this paper, one consequence of a change in the normal operating mode of the MTVZA-GYa Russian microwave scanner/sounder—the significant decrease in the accuracy of georeferencing of this device measurements data that occurred April 2022—has been examined. Deterioration in accuracy during retrospective thematic processing of MTVZA-GYa data at the stage of visual analysis of the input data quality has been found. The displacement of radio thermal portraits relative to the real coastline is ~70 km. The analysis of described changes is carried out in two stages. At the first stage, during an manual review of measurement data from each half-orbit, it is possible to determine the time frame of the failure (from April 10 to May 25) and identify the main cause of the observed displacements: a change in the yaw angle of MTVZA-GYa. At the second stage, as a result of end-to-end machine processing of the daily composites formed by the instrument, an accurate value of the changed angle has been determined and amounts to (–2.64 ± 0.23)° (instead of (–0.84 ± 0.15)° used in normal mode). These studies have demonstrated the possibility of using the algorithm for determining MTVZA-GYa georeference-correcting angles as an indicator of failures in the operation of individual systems of this instrument. The potential possibility of adjusting the georeferencing of MTVZA-GYa measurements in the event of such failures has been also demonstrated. In particular, it is possible to reduce the georeferencing error by almost six times for the case considered in this study.