A Phase Compensation Beam Switching Antenna Based on Frequency Selective Surface

In this letter, the phase compensation method is used to analyze and design the cylindrical frequency selective surface (FSS), and a beam switching antenna is proposed to verify the correctness of this method. The proposed antenna includes an omnidirectional dipole and a phase adjustable active frequency selective surface around it. To steer and gather the pattern of the dipole, each FSS structure is embedded varactors with an orderly bias voltage under the guidance of the phased compensation method. The proposed antenna achieves the characteristic of a high gain of 13.3 dBi at 2.45 GHz while satisfying the beam switching with a 20° step. The measured results of the fabricated prototype are in good agreement with the simulated ones. This antenna can be widely used to improve the signal distribution and the quality of wireless communication systems.

I. Introduction

The omnidirectional coverage characteristics of indoor terminal antennas can ensure that there is sufficient signal coverage in every corner of the room. When people's activity area is fixed or more people gather in a certain area, there will be problems of signal energy waste and insufficient capacity. The indoor signal distribution, as required, is needed to be improved [1]. In this case, the antenna design with flexible characteristics and high quality of transmission plays an important role. Therefore, the beam switching antenna (BSA) has aroused great interest. Some other notable features of BSA, such as reconfiguration and multipath attenuation reduction, make it applicable to military, satellite networks, and point-to-multipoint links of base stations [2], [3].