D.D. Gabrielyan1, V.I. Demchenko2, A.O. Kasyanov3, A.A. Kosogor4

1-4 FSUE “Rostov-on-Don Research Institute of Radio Communication” (Rostov-on-Don, Russia)

1 d.gabrielijan2011@yandex.ru; 3 kasyanovao@sfedu.ru

In the previous paper of the authors, an indicator of the effectiveness of the use of an onboard radar complex of space-based remote sensing of the Earth is proposed in the form of a weighted multiplicative function of target characteristics, such as the area of sensing per unit time, resolution on the ground, radiometric sensitivity and resolution. The proposed indicator and the results obtained are largely of a methodological nature, illustrating a possible approach to assessing the effectiveness of the use of an onboard radar complex of space-based remote sensing of the Earth. This paper further develops these issues and proposes an extended indicator of the effectiveness of using the onboard radar complex for remote sensing of the Earth from a spacecraft, taking into account the system's resource limitations, particularly the maximum level of radiated power and the size of the antenna's radiating aperture in the transverse direction.

The performed studies have shown that the angular-altitude dependences of the target functions in the range of heights of 300-2500 km and angles of 10... 46,5°, taking into account the levels of limitations on the resources of the on-board radar complex, have a monotonously increasing character for target functions that do not depend on the energy potential of the on-board radar complex, for example, the sensing area per unit time, and for target functions that are clearly time-dependent, for example, radiometric sensitivity and resolution, may have two sections, on the first of which the values of the target characteristics remain unchanged, and on the second their deterioration is observed, leading to a decrease in the expanded generalized indicator of the effectiveness of the on-board radar complex.

The angular-altitude dependencies of the extended indicator of the effectiveness of using the onboard radar complex of the spacecraft in the aperture synthesis mode in the same ranges of altitudes and angles, depending on the weight of each of the target functions, may have one to three sections:

Section 1: at small angles of deviation of the beam from the nadir direction and a high level of energy potential, there is only one section of monotonic increase;

Section 2: with an increase in the beam deviation angle, it is possible for three sections to appear in the considered dependence, the second of which is caused by a predominant decrease in radiometric parameters over an increase in the probing area per unit time, and the third – by a predominant increase in the probing area per unit time over a decrease in radiometric parameters;

Section 3: with a decrease in the energy potential of the onboard radar complex for both small and large angles, with an increase in altitude, a section appears to decrease the extended indicator of the effectiveness of the use of the onboard radar complex of the spacecraft, which is caused by a predominant decrease in radiometric parameters over an increase in the probing area per unit time.

The clear relationship between the target characteristics and the altitude-angle parameters of Earth remote sensing obtained during the analytical study allows us to identify the most significant patterns of behavior of the generalized indicator of the effectiveness of using an onboard radar system.

Gabrielyan D.D., Demchenko V.I., Kasyanov A.O., Kosogor A.A. A generalized efficiency index of the spacecraft radar use to solve the remote sensing of Earth problems by synthesizing the aperture Part 2. Optimization with constrains for generalized efficiency index. Radiotekhnika. 2025. V. 89. № 11. P. 31−42. DOI: https://doi.org/10.18127/j00338486-202511-03 (In Russian)

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