K.V. Kamenskiy1

1 Moscow Aviation Institute (National Research University) (Moscow, Russia)

Background. The backprojection method is used to obtain radar images of superior quality in synthetic aperture radar signal processing, however, this method makes high demands on computational performance. Range-Doppler algorithm can be used as a faster alternative which by using the same track signal model makes assumptions that allow to simplify processing for the computer in exchange for possible worsening of radar image quality, including those caused by track instabilities influence. This algorithm requires extensions that bring obtained radar image quality closer to the quality of radar images got by the backprojection method. Radar carrier motion compensation methods and range cell migration correction methods belong to such extentions.

Aim. The aim is to develop solutions for two important operations of the Range-Doppler algorithm, namely, radar carrier motion compensation and range cell migration correction. The track signal processed is assumed to belong to a side-looking stripmap continuous wave radar with non-symmetrical periodic linear-frequency modulation.

Results. The track signal model fundamental for the Range-Doppler algorithm was examined. The Range-Doppler algorithm was described with this model in general terms, as well as the point of its primary operations was explained. A new method of motion compensation and a new algorithm for range cell migration correction were developed. Numerical experiments were conducted where the developed methods were compared to the methods known before. Advantages and disadvantages of the developed methods were identified.

Practical value. The developed motion compensation and range cell migration correction methods can be used in Range-Doppler algorithm implementations for synthetic aperture radars placed on board of unmanned aerial vehicles.

Kamenskiy K.V. Motion compensation and range cell migration correction in track signal processing in continuous wave synthetic
aperture radar. Radiotekhnika. 2022. V. 86. № 7. P. 121−141. DOI: https://doi.org/10.18127/j00338486-202207-19 (In Russian)

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