Spaceborne HF/VHF-radar system for ionosphere sounding

Ionosphere sounding is of significant importance for compensating ionospheric effects on satellite communication, navigation and remote sensing systems at lower frequency, i.e. L-band, P-band etc.. A novel spaceborne HF/VHF-radar scheme is proposed for ionosphere sounding. Based on Frequency Division (FD) technique, the mode for large-scale ionospheric structure sounding can generate a two-dimensional (2D) topside electron density image. Based on synthetic aperture technique, the mode for small-scale ionospheric irregularities imaging can generate a 3D irregularities image. The effectiveness of the proposed SAR system was verified by means of computer simulations. The simulation results show that the resolution of large-scale sounding mode is as high as 0.49km, and the resolution of small-scale sounding mode is as high as range 0.9km, azimuth 0.27km and across-track 0.25°.