Analysis of spatial/polarization diversity using a broadband slot-coupled patch antenna for the WLAN 802.11A/B/G/N access point

A broad dual-band slot-coupled patch antenna is proposed for the wireless local area network band. The basic antenna element consists of two radiators on three layers. To enhance the bandwidth, a coupled feeding was used in the first radiator, and a parasitic patch was used in the second radiator. The peak gain of the single antenna element was more than 6 dBi at 2.4 GHz and more than 8 dBi at 5 GHz. We simulated and measured the extended antenna to four elements using a common reflector, and the spatial and polarization diversity of the proposed antenna were analyzed according to the isolation and the diversity gain. The isolation is below -15 dB at the operating frequency when the distance between the proposed antennas is more than 0.67λ (80 mm). The orthogonal polarization of the proposed antenna obviously improves the performance of the diversity antenna system.