I. O. Kolachev1
1 Baltic State Technical University “VOENMEH” named after D.F. Ustinov (St. Petersburg, Russia)

1 kolachev_io@voenmeh.ru

Modern high-resolution radar systems are highly informative measurement systems for remote sensing of the Earth. A promising tool for calibrating such systems is the use of active repeaters (transponders), which form virtual objects on radar images. The scattering characteristics and location of these virtual objects can be controlled electronically. Due to the multi-channel nature of modern digital systems, a single transponder can potentially replace a full-fledged calibration radar polygon. However, this is hindered by the fact that the radar images of virtual objects far from the real location of the transponder are often not point-based, but group-based due to image defocusing.

The purpose of the article is to improve the method of forming virtual objects for high-resolution radars using active transponders, developed by a team including the author of this article. To achieve this goal, the objective has been set to conduct research to enable a significant expansion of the permissible offset values of the formed virtual objects relative to the transponder, at which they could be used to solve applied problems.

The method for forming virtual objects for high-resolution radars using active transponders has been improved, which has been confirmed by the results of mathematical modeling. The limitations of the method and the requirements for the accuracy of determining the quantitative values of the used parameters have been evaluated. A modified transponder structure implementing the enhanced capabilities of this method has been proposed.

The results obtained can be used to improve the quality of information extracted from the radar, which will increase the efficiency of Earth remote sensing systems.

Kolachev I.O. Advanced method for forming virtual objects for high-resolution radars using active repeaters. Antennas. 2026. № 2. P. 60–70. DOI: https://doi.org/10.18127/j03209601-202602-06 (in Russian)

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