A multiband circular-annular ring patch antenna for wireless applications

A circular annular-ring microstrip patch antenna with perturbed circular patch and L-shaped orthogonal strips, used for multiband applications is proposed. FR4 is the substrate material used with dielectric constant of 3.68 and the antenna is feed using 50Ω coaxial probe. Meandering techniques and modified orthogonal L-shaped strips are utilized to give resonator effects. The proposed antenna offers multiband response at resonant frequencies of 2.4 GHz, 5.95 GHz, 7 GHz, 9.55 GHz and 11.35 GHz. The simulated results show good performance with a minimum reflection loss of −25 dB, gain within the range of 3–5 dB and VSWR<2 at desired frequencies.