In recent years, the advantages of multi-sensor integration are gradually highlighted. In this paper, an integrated imaging system (IIS) of airborne synthetic aperture radar (SAR) and visible light camera (VLC) based on common aperture antenna is designed to meet the mission requirement of acquiring visible light and SAR images simultaneously. The IIS adopts the coaxial scheme, its structure is simple and compact, and is more suitable for airborne platform. In this paper, a parameter design method of IIS based on common aperture antenna is proposed. After the system parameters design, the imaging performance of IIS is analyzed by simulation. The results show that the system parameters are designed reasonably and the imaging performance meets the mission requirement. The designed IIS can realize the visible and Ka-band (30 GHz) dual-band imaging. Under the condition of 20 km altitude, the imaging resolutions of VLC and SAR are higher than 0.2 m and 0.3 m respectively, the field of view of VLC is 1.46°, and the swath length of SAR is greater than 870 m.

Metalenses have attracted much attention from researchers because they are thin, multifunctional and easy to integrate. However, due to the limitation of fabrication techniques and the influence of working wavelength, it is difficult to realize a large aperture. In this paper, we design and simulate polarization-insensitive, orthogonal linearly polarized and orthogonal circularly polarized synthetic aperture metalenses. We use a synthetic aperture to improve the cutoff frequency of the metalens and achieve an equivalent large-aperture metalens. We compare the modulation transfer function and focusing efficiency of synthetic aperture metalenses with different array structures. This work provides an effective solution to the needs of large-aperture metalenses, and metalenses with different polarizations can play an important role in polarization imaging.

The integrated imaging of LWIR cameras and SAR is one of the important directions of multi-sensor integration. In order to reduce the structural complexity of LWIR cameras and SAR-integrated imaging antenna, a dual-polarized metasurface-integrated antenna (MIA) is designed in this paper. It is composed of a microwave metasurface antenna and an optical metalens, and the metalens is embedded in the center of the metasurface antenna. The MIA uses the powerful electromagnetic wave control ability to simplify the optical and microwave signal transmission paths and reduce the number of devices. At the same time, in order to expand the function of the MIA, based on the principle of metasurface, the dual-linearly polarized and dual-circularly polarized MIAs are designed and simulated, respectively. The results show that the designed dual-polarized MIA has good performance. This paper provides a new scheme for the integrated imaging system of LWIR cameras and SAR with simple structure, diverse functions and easy integration.