Parallel Coplanar Waveguide-Fed Antenna Design for Full-Duplex Wireless Systems

This paper aims to construct a slot antenna using an inductive feeding structure in the Coplanar Waveguide (CPW) transmission line in the 24-GHz radar application with high isolation directional duplexer characteristics, in addition to the advantages of low loss and high efficiency of CPW transmission lines. The 180-degree phase difference between the two paths generates an electric field with a zero-point position symmetric to the feeding port. Therefore, the characteristics of the dual paths are designed to obtain full-duplex and high-isolation improvements. According to the proposed structure of the slot antenna with the CPW transmission lines, the antenna radiation efficiency and gain are over 80% and 7 dBi, respectively at 24 GHz. Moreover, for the antenna realization, the transition design of Coplanar Waveguide with Ground (CPWG) to CPW is implemented for this duplexing antenna measurement. At last, the electromagnetic simulation results are provided for optimization, including the geometric parameters to analyze the resonate frequency of the antenna design. Due to the inductive feed, the antenna has a compact size for the further assembly stage of the packaging.