A dual band polygon shaped CPW-fed planar monopole antenna with circular polarization and isolation enhancement for MIMO aplications

In this study, design and characteristics of a circularly-polarized (CP) CPW-fed monopole antenna is presented. This antenna operates in the ISM and WLAN bands. To improve isolation, a new configuration in microstrip antenna arrays is applied. The antenna has a compact aperture size of 20 × 20 mm
²
which is simulated on FR4 substrate with dielectric constant of 4.4 and thickness of 1 mm. Results indicate that the return loss of this antenna is lower than -10 dB in 2.2-8.0 GHZ band. In addition, the antenna with a 3-dB axial ratio has the bandwidths of 36% and 17% for lower (2150-3100MHz) and upper (5150-6100 MHz) bands, respectively. The results of this investigation can be used to optimize the design of multiple-input-multiple-output (MIMO) communications.