Asymmetrical coplanar waveguide zeroth-order resonant antenna with extended bandwidth

This paper presents the design and analysis of a compact coplanar waveguide (CPW)-fed zeroth-order resonant (ZOR) antenna with extended bandwidth. Two new resonant frequencies are obtained by adding two stubs between the main patch and the CPW ground. With the combination of the ZOR frequency and the two new resonant frequencies, a wide bandwidth is achievable and increased up to 58.4%. The efficiency of the antenna is higher than 85% in the entire band from 3.7 GHz to 6.75 GHz. The proposed antenna has a compact size of 21mm×19mm and an omnidirectional radiation pattern, which is applicable in wireless applications at C-band.