English title

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In this paper, a SIW horn antenna is designed using Luneburg lens in order to enhance the gain. Using a transition printed on the same substrate, both the matching performance and the front to back ratio was improved. In addition, this transition structure allows the antenna to be planar. The proposed antenna operates at 14.5 GHz and can be used for Ku band application.An antenna prototype was fabricated and tested, showing an agreement between simulation and measurement.

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The present work applies the holographic technique to develop a leaky-wave antenna based on spoof surface plasmon polariton with circular polarization. For the first time, an impedance surface (hologram) with an anisotropic unit cell (with a hollow metallic cross-bars shape) without a ground plane is implemented to control the radiation polarization of the leaky wave structure. We used a combination of optical conversion relations and a particle swarm optimization algorithm to estimate the anisotropy of the proposed unit cell. By changing the dimensions of the cross's two arms and rotation angle, the required components of the surface impedance tensor are determined to realize the hologram. The realized gain, radiation efficiency, sidelobe level, and axial ratio bandwidth are 15.3dBi, 82%, -11dB, and 11.8%, respectively. The maximum scanning angle of was obtained when the frequency varies from f = 16 GHz to f = 18 GHz. The simulations were performed in MATLAB and CST Microwave Studio.