Çok Geniş Bantlı Doğrudan Beslenmiş Radomlu Çift Konik Anten Analiz ve Tasarımı

Abstract

A large number of available omnidirectional antennas are narrow band which causes difficulties such as the use of multiple antennas for different frequency bands. The widespread use of omnidirectional antennas in different frequency bands makes the design of broadband omnidirectional antennas a necessity. The biconical antenna is one of the best-known omnidirectional antennas that meets this necessity. In the literature, biconical antennas are divided into two categories as narrow angle and wide angle. Narrow angle biconical antenna shows similarities with dipole antenna. For this reason, the dipole antenna is intended to be used as a reference in verifying the function of biconical antennas. Impedance mismatch as one of the important problems in antenna design, is usually solved by an impedance matching circuit integrated into the antenna input. However, as a more practical solution, the antenna impedance can be matched to the impedance of the feed line during antenna design. This technique, called direct feed, is aimed at the use of biconical antenna. Radome protects the antenna from environmental factors. However, the radome must not affect the electromagnetic wave propagation while the antenna is protected from this environmental factors. Fulfilling these two requirements, makes radom design an engineering problem. The use of radomes designed as sandwich and monolithic, especially for antennas on the ground, is vital. In the first part of this thesis, it is aimed to design a wideband biconical antenna in accordance with the direct feed technique. In the second part, a radome design suitable for wideband applications is investigated. Following that, the antenna and radome are both manufactured after optimization process and the test results are included in the thesis.