A High-Gain Dual-Band Multibeam Antenna System for MIMO Wi-Fi Application

A compact dual-band multibeam antenna system with high gain is presented for multiple-input-multiple-output (MIMO) wireless fidelity (Wi-Fi) application. The antenna system is composed of four rotationally symmetric antenna panels occupying a compact size of $60\times 200\times7.2$ mm ³ . Two series-fed microstrip patch antenna (MPA) arrays are proposed to operate at the 5-GHz band. They are fed with ±90° phase difference signals for two directional radiation patterns with about 45° horizontal 3-dB beamwidth and distinct radiation directions. Two dual-function metasurface based on periodically loaded parallel lines is designed and compactly placed between the two MPA arrays. The metasurface works as a 2.4-GHz antenna with about 90° 3-dB beamwidth in the azimuth. Besides, the application of metasurface improves the gains at the 5-GHz band. Then, four antenna panels are placed in a rotating arrangement with an electric size of $0.59\lambda _{\mathrm {L}} \times 0.59\lambda _{\mathrm {L}} \times 1.57\lambda _{\mathrm {L}}$ ( $\lambda _{\mathrm {L}}$ is the free-space wavelength at the lowest operating frequency). The antenna system was manufactured and demonstrated the characteristics of 360° pattern coverage in azimuth and high gain. The measured average gains are, respectively, higher than 8 and 12 dB at the 2.4- and 5-GHz bands.