Design of the Dielectric Resonator Antenna Operating at Dual Microwave/Millimeter-wave Frequencies for Wireless Communications

Description

As compared with the third-generation (3G) mobile communication, the fourth-generation (4G) system provides a much higher data rate and hence better enjoyments of mobile devices. However, with the rapid developments of mobile internet network and internet of things, it is anticipated that much faster data rates will be needed in the foreseeable future. To meet the need, the fifth-generation (5G) system is being actively developed and would be available around year 2020. While the 4G system is operated in the microwave (MW) band, it is almost certain that the 5G network will be operated in the millimeter wave (MMW) band. Thus, to obtain a smooth transition, the 5G system should also support the existing MW 4G system. As a result, it will require dual-frequency wireless systems that can be operated in both MW and MMW bands. Existing dual-frequency MW/MMW antennas were designed on planar (2-D) structures such as patch/reflectarray antennas. Since the design flexibility of 2-D structure is limited, the MW/MMW antennas have been obtained by just putting two separate MW and MMW antennas together, with no integration or optimization to reduce the antenna size and weight. In this project, the three-dimensional (3-D) dielectric resonator antenna (DRA) is used to provide one more degree of freedom for the design. Other advantages of DRA include its small size, low loss, ease of excitation, and relatively wide bandwidth as compared with the microstrip antenna. For the first time, the MW DRA will be integrated with MMW antennas to obtain very compact hybrid MW/MMW antennas. In this project, both high- and low-gain MMW antennas will be used to meet different needs of MMW systems. In the former, the high-gain resonant cavity antenna (RCA) obtained from a hollow DRA will be used. Also, the circularly polarized hybrid DRA/RCA antenna will be investigated in the project. For the latter, the low-gain Fabry-Perot resonator antenna (FRPA) fabricated from the U-shaped DRA will be used. The hybrid DRA/FPRA design will be extended to obtain dualband/wideband characteristics for each of the MW and MMW bands. The hybrid antennas will be designed using Ansoft HFSS and substantiated by measurements. Systematic parametric studies will be carried out, and design guidelines will be given to facilitate designs of the hybrid antennas