Gain Enhancement of Horn Antenna Using Novel Metal Lens

Description

In wireless communications, the antenna is the front end that directly affects the quality of signal transmission and reception. In general, power loss in the air can be reduced by increasing the antenna gain, which can be achieved by using lenses. Practically, most communication systems provide only a limited space to accommodate the antenna, therefore a compact, high-performance lens is highly desired. To obtain a wider bandwidth and a faster data speed, the use of millimeter-wave (mm-wave) systems has been more extensive than ever. This frequency band will be included in this project. The horn antenna has been widely found in communication systems due to its simple structure, ease of excitation, and stable radiation pattern. Thus far, the metasurface and dielectric lens have been commonly used to increase the gain of a horn antenna. These designs suffer from either the need of an antireflection coating or a limited operating bandwidth. However, not much attention has been paid to the metal lens to increase the gain of the horn antenna. Compared with the dielectric lens, the metal lens has a lower cost and can handle much higher power. With the advancement of 3D-printing technology, metal lenses of different shapes can be integrated with a horn antenna easily, and the entire integrated design can be fabricated in one go. In this project, a novel metal lens is proposed for the first time to increase the horn antenna gain. It can be compactly integrated with the horn antenna. The shape of the metal lens will be studied to optimize the antenna size and performance. Also, a modified metal lens will be investigated to reduce the profile of the first design. Next, a compact, wideband circularly polarized (CP) mm-wave horn antenna will be designed with the proposed metal lens. To generate a CP wave, it needs two orthogonal E-fields which are in phase quadrature. This project will deploy two metal lenses for the two E-fields, making it challenging to obtain a compact, wideband design. The difficulty will be overcome in this project. Today, the microwave system is still extensively used due to its mature technology, lower cost, and larger signal coverage. In this project, a dual-frequency antenna integrated with the proposed lens will be investigated for microwave and mm-wave applications. In each part, a guideline will be given to facilitate the antenna design.