A Broadband Multimode Antenna With Enhanced Gain and High Efficiency by Employing Metasurface for WLAN and Car-to-Car Application

Abstract

A multimode resonance patch antenna with the attractive radiation gain and efficiency is investigated in this paper. A driven patch with both sides shorted similar to the cavity model is presented to generate TM03 and TM11 modes. TM21 mode is also excited by inserting five shorting parasitic patches on both sides of the radiation aperture to extended the impedance bandwidth and no additional feeding structure is required. Meanwhile, a novel metasurface with the positive gradient of the reflection phase is placed directly above the proposed multimode antenna. Then the characteristics of high gain and better front-to-back ratio (FBR) are acquired. The measured results show that the characteristics of 20.7% impedance bandwidth from 5.08 GHz to 6.25 GHz, stable gain of up to 12.34 dBi, high radiation efficiency of up to 89% and cross-polarization level below −20 dB are obtained. These characteristics all imply that the proposed antenna can be applied to WLAN and Car-to-Car (C2C) communications.

Keywords

• Multimode
• patch antenna
• shorting parasitic patch
• metasurface
• front-to-back ratio
• radiation efficiency