F-shaped monopole based MIMO antenna for WLAN applications

In this paper, A triple band multiple-input-multiple-output (MIMO) antenna array is proposed for a conveyable wireless device for WLAN applications (band 1: 2.4 - 2.484 GHz, band 2: 5.15 - 5.35 GHz, and band 3: 5.725 - 5.825 GHz). The proposed antenna array consists of two monopole antenna components which are separated by approximately one-tenth of the wavelength of the lower frequency band (2.45 GHz). In order to reduce the radiator size, it is designed in the shape of F and the two branches of F are responsible for producing the designated frequency bands. The resonance centered at 2.45 GHz is covering band 1 while the resonance centered at 5.4 GHz is covering band 2 and band 3. Both the elements are the mirror image of each other over a partial ground plane with FR-4 as substrate. Furthermore, the optimal coupling between two elements is achieved by cutting a dumbbell shaped cut-out within the ground plane between the antenna components. The measure of proposed antenna is only 35 × 40 × 1.6 mm3. In addition, the characteristic of small size, nearly omnidirectional coverage and good diversity performance make the proposed MIMO antenna suitable to the mobile WLAN applications.