Ultra-wide band reflector antenna design by development of multiple object analytical regularization method

In today's wireless technologies, the transmission of ultra-wideband and short-pulse signals are gaining importance for civilian and military systems. For these types of systems, ultra-wideband performance of the radiator is crucial for transmitting signals over long distances without distortion and loss of information. In this thesis, single and dual reflector antennas are designed to achieve high gain and efficiency for ultra-wideband operation and impulse radiation. Besides, various types of UWB feeders are also developed to operate at different frequency bands. For this aim, a new numerical approach of Analytical Regularization Method (ARM) is developed for UWB analysis of electrically large multiple part reflector antennas. On this scope, the 2D Analytical Regularization Method for multiple objects scattering is newly introduced to simulate electrically large antennas which have multiple components. The developed method is convenient for UWB investigations of the reflector antennas. In order to refrain long simulation durations and high memory consumption at 3D EM simulators, this numerical method is proposed for fast and accurate pre-analysis of the antennas. As a single reflector type, a 90 cm offset UWB reflector antenna is created using TEM ridged horn antenna (TEM-RHA) feeder, which is a combination of Vivaldi TEM horn and ridged horn, to operate between 0.4 GHz and 15 GHz. With an excellent bandwidth ratio of 35:1, the designed offset antenna is suitable for impulse radiation. Furthermore, a 60 cm of diameter onset reflector antenna is utilized with ridged horn for higher frequencies with broadband from 1.6 GHz up to 20 GHz. The onset reflector design is capable of superior efficiency performance up to 61% for UWB operation. As a double reflector type, a highly efficient switchable axially displaced elliptical (ADE) dual reflector antenna is designed as an innovation for UWB applications. Two types of feeder, which can be manually switchable, are developed for same dual reflector structure. The first feeder, K-Vivaldi antenna, is appropriate for impulse radiation with 33:1 bandwidth that operates from 0.6 GHz to 20 GHz. Additionally, K-Vivaldi feeder is loaded with a partial dielectric to enhance its gain performance at higher frequencies. The second one, double ridged horn antenna, feeds the dual reflector geometry to achieve higher gain and efficiency performances with 12:1 operational bandwidth, which corresponds to 1.6 GHz and 20 GHz. The proposed dual reflector antenna has significant volume advantage compared to the single reflector designs. ADE structures with various curve functions and different focuses are investigated for better radiation performance. The antennas are designed by developed 2D multiple object ARM and parametrically optimized by 3D EM simulator to succeed better perfomance and then, produced and measured. Finally, obtained measurement results are compared to each other, and they are observed compatible with simulations.