چكيده به لاتين
In this thesis, a novel approach, called Rays Inserted Method (RIM), is introduced to design dielectric microwave and optical devices with arbitrary shape and exciting source. In this approach, some rays are inserted between two ends of desired device and then the refractive index of the points along the route of rays are obtained. So inhomogeneous refractive index of device is resulted. The designed structures are matched to the source antennas and environment refractive index, resulting in an acceptable voltage standing wave ratio (VSWR). Search and track radars are two main kind of radars witch vastly used in defense systems. Wide angle search are required in some of the modern radar and satellite systems operating at millimeter wave and microwave frequency bands such as weather radars, tracking systems and remote sensing applications. Elliptical lens is used in search radars must radiate fan-beam radiation pattern. In this thesis, broad band inhomogeneous elliptical lenses are presented based on RIM approach and transformation optics theory to result special fan beam radiation patterns. Vertical and horizontal plane of these fan beam radiation patterns can be controlled separately. The proposed structures are validated using software of COMSOL MULTYPHYSICS and CST. A type of hemispherical lens has been fabricated. The results of experiment indicate good performances of realized lens in a wide frequency bandwidth. Comparing with other hemispherical lenses like classical half Maxwell fish-eye, the improvements in the gain, side lobe levels, and input matching are achieved by using RIM.
