Design of a Wideband Omnidirectional Antenna With Characteristic Mode Analysis

A low-profile horizontally polarized (HP) omnidirectional metasurface-inspired antenna is presented. To realize HP omnidirectional radiation pattern, the theory of characteristic mode is utilized to facilitate the analysis of three antenna structures. Then, by properly exciting the desired characteristic mode, the antenna with a wide bandwidth and good omnidirectionality, which is based on the modification of the standard patch antenna, is obtained. The simulated results show that the proposed antenna not only can obtain a low profile of 0.06λ0 (where λ0 is the free-space wavelength at 5.2 GHz), but also has a wide operating bandwidth of 16.6%. Finally, the metasurface-inspired antenna is manufactured and the error analysis between the simulated and measured results is also provided. The antenna can be applied to 5G wireless local area network systems.