Study and design of compact quasi optical beam forming lens antennas in a parallel plate waveguide technology for on boards satellite constellation missions

Abstract

The activities presented in this Ph. D thesis focus on the design of Quasi Optical Beam Forming (QOBF) antennas in a parallel plate waveguide (PPW) technology and find applications in satellite constellation missions. The antenna technology that has been investigated is the graded index Gutman lens antenna in a PPW technology. In the first part of the thesis the all-metal Gutman lens with focal arc f=R/2 has been analysed, designed, manufactured and experimentally tested. Besides, a more compact all-metal GRIN Gutman lens with smaller focal arc equal to f=R/2.85 has been designed. Both all-metal Gutman lenses operate at Ku-band and have been compared to the all-metal GRIN Luneburg lens. Next, the equivalent dielectric lenses, Luneburg lens, Gutman lens with focal arc f=R/2 and Gutman lens with focal arc f=R/2.85 have been designed using non-dispersive dielectric layers. A comparison between all-metal and dielectric lenses has been presented. The last part of the thesis focus on the optimization of the all-metal continuous delay line lens antenna in a PPW technology. A design methodology of the transversal ridge of the lens has been proposed based on the axis inversion of the ellipse together with a multiobjective optimization technique. The optimized lens antenna provides an isoflux envelope mask and has a wide field of view.