A high resolution 2D omnidirectional synthetic aperture radar scanner at K band

In this paper a K-band 360° 2D imaging radar utilizing a synthetic aperture scanning principle is introduced. A small omnidirectional antenna is mounted on a rotating platform to create a circular synthetic aperture. Based on a broadband holographic reconstruction principle a high resolution 360° 2D image is calculated after each turn of the platform. The size of the synthetic aperture and thus the lateral resolution of the imaging system are determined by the diameter of the resulting circular antenna trajectory. In contrast to common radar scanner-concepts that utilize highly directional and thus bulky antennas, the proposed scanner concept has the advantage that it uses a small and lightweight omnidirectional antenna. This results in a much more compact radar system with notably relaxed requirements for the scanning mechanics. In addition it will be shown that the use of an omnidirectional antenna allows for very simple options to transfer energy to the radar on the rotation platform. The performance of the proposed SAR radar scanning method is illustrated with a 24 GHz FMCW radar sensor system.