CB-CPW fed compact dual band antenna for WLAN applications

A low profile microstrip dual band antenna with conductor backed coplanar waveguide (CBCPW) feed is proposed for wireless local area network (WLAN) applications. In conventional CPW feeding, the upper surface of the antenna substrate has a centre strip conductor with semi-infinite ground planes on either side. The CBCPW fed antenna has an additional metallic coating at the back side of the substrate. The extra coating not only provides mechanical support to the substrate, but also works as a heat exchanger for electronic circuits with active devices. The antenna is designed on a flame retardant woven glass reinforced epoxy resin (FR4) substrate having permittivity 4.4 and loss tangent 0.02. The proposed design has achieved dual band operation with a compact size of 20×20×1.6 mm³. The IE3D software simulation results show that the proposed antenna has a good bandwidth efficiency at 2.59/5.38 GHz and it meets the necessities of IEEE 802.11 standard.