Fig. 1. Comparison of perpendicular-orbit circular scanning sensor with pushbroom sensor imaging mode

Fig. 2. Schematic diagram of dual-camera imaging

Fig. 3. Comparison of instantaneous image coordinate system between vertical orbit ring scanning sensor and pushbroom sensor

Fig. 4. Schematic principle for back project calculation

Fig. 5. Curves of back project calculation

Fig. 6. Flow chart of back project calculation and improved algorithm

Fig. 7. Interface of simulation image software

Fig. 8. Schematic diagram of image range

Fig. 9. Invalid points of back project calculation

Fig. 10. Histogram of back project calculation error

Fig. 11. Vector diagram of back project calculation error

Fig. 12. Error of RFM in different widths