A compact microstrip fed dual polarised multiband antenna for IEEE 802.11 a/b/g/n/ac/ax applications

A compact microstrip fed dual polarised multiband monopole antenna for IEEE 802.11 a/b/g/n/ac/ax communication based applications is presented. The antenna is circularly polarised in IEEE 802.11 b/g bands while linearly polarised in IEEE 802.11 a/n/ac/ax bands. The asymmetric U-shaped slot in the ground plane of proposed antenna is used to introduce the necessary 90° phase shift between two orthogonal electric field vectors necessary for circular polarisation. The Ω-shaped slot on patch is used to introduce a band elimination notch between the usable frequency bands. The radiation characteristics of the proposed antenna (at 2.4 GHz) can be changed from left hand circular polarisation (LHCP) to right hand circular polarisation (RHCP) by replacing asymmetric U-shaped slot with its mirror image on the opposite side of ground plane. The proposed antenna has a wide impedance bandwidth of 110.8% and can also be used in various applications including worldwide interoperability for microwave access (WiMAX) and IEEE 802.11p standard based V2V (Vehicle to Vehicle) communication.