The paper presents a method of calculation of position deviations from a theoretical, nominally rectilinear trajectory for a SAR imaging system installed on board of UAV. The UAV on-board system consists of a radar sensor, an antenna system, a SAR processor and a navigation system. The main task of the navigation part is to determine the vector of differences between the theoretical and the measured trajectories of UAV center of gravity. The paper includes chosen results of experiments obtained during ground and flight tests.

In order to obtain good quality radar terrain images using an aerial-based synthetic aperture radar, a motion compensation procedure must be applied. This procedure can use a precise navigation system in order to determine the aircraft’s position and velocity. A major challenge is to design a motion compensation procedure that can operate in real time, which is crucial to ensure convenient data for a human analyst. The article discusses a possibility of Inertial Measurement System (INS)/Global Positioning System (GPS) navigation system usage in such a radar imaging system. A Kalman filter algorithm designed for this system is described herein, and its modifications introduced by the authors allow the use of navigational data not aligned in time and captured with different frequencies. The presented navigation system was tested using measured data. Radar images obtained with the INS/GPS-based motion compensation system were compared to the INS-only results and images obtained without navigation corrections. The evaluation results presented in the paper show that the INS/GPS system allows for better reduction of geometric distortions in images compared to the INS-based approach, which makes it more suitable for typical applications.

The article presents a navigation system used to improve the quality of terrain images obtained from a Synthetic Aperture Radar (SAR) installed on a miniature unmanned aerial vehicle. An inertial navigation system is used to determine the flight path deviations from an assumed straight line. Calculated position corrections are used to correct the phase of the received echo signal in order to get a focused SAR image. The paper describes chosen results of in-flight experiments, presenting the influence of navigation correction on SAR images.

The paper presents a method of calculation of motion correction parameters for a Synthetic Aperture Radar (SAR) installed on an Unmanned Aerial Vehicle (UAV). The UAV on-board system consists of a Radar Sensor, an Antenna System, a SAR Processor and a Navigation System. The main task of the navigation part is to determine the vector of difference between a theoretical and a real trajectory of the UAV's center of gravity. The paper includes chosen results of experiments obtained during ground tests.

No abstract