프레넬 영역 내에서 평면파를 발생하는 도파관 혼 어레이 안테나의 급전부 설계 연구

Abstract

This thesis describes the 6-way power divider to be used as a feeding structure of the waveguide array antenna generating plane wave at the near distance. The SMA connector has been connected at the center of the power divider in order to feed the radiating element. The six output ports made of waveguide are positioned on the peripheral of the divider. This thesis proposes the method utilizing the inductive post in order to decrease the return loss. The height of the feeding pin, the diameter of the inductive post, and the distance between the feeding pin and inductive post have been investigated, and, as a result, the power divider has been optimized. The simulated and measured results show the low return loss of about -40 dB. The calculated and measured transmission coefficients are -7.78 dB and -8.06 dB, respectively. The output power of the six waveguide port show equal-amplitude and equal-phase distribution. For good impedance matching over a broad frequency band, a metallic wall with an inductive component is positioned on the side of the output waveguide. Simulated and measured results indicate low return loss and low insertion loss. Compared to a waveguide divider with an inductive post, the proposed divider offers a much broader bandwidth of 9.4 % and 14.8 % from the simulation and measurement results. Since the power divider proposed in this thesis can be expanded to the divider having several output ports, it could be easily applied to the various array antennas.