Radiation Properties Enhancement of a GSM/WLAN Microstrip Antenna Using a Dual Band Circularly Symmetric EBG Substrate

This communication presents a dual band circular patch antenna with improved radiation properties at GSM and WLAN frequency bands, i.e., 1.8 and 2.4 GHz. The improvement has been achieved using a dual band circularly symmetric EBG (CS-EBG) structure. The structure has been simulated, fabricated and measured demonstrating notable enhancement in antenna radiation patterns at both frequency bands. Results show 5 dB and 7 dB improvement in front to back ratio at design frequencies of 1.8 GHz and 2.4 GHz respectively. In addition, measurement results demonstrate 0.8 dB increase in antenna gain and significant reduction in cross polarization level at both frequency bands.