Design of Triple Band Slot-Patch Antenna with Improved Gain Using Triple Band Artificial Magnetic Conductor

A CPW-fed triple band slot-patch antenna is designed to resonate at 3.60 GHz, 5.86 GHz and 8.53 GHz. The structure makes use of two types of radiators. A slot structure is made which behaves like a half wave dipole at 3.60 GHz. The other two resonating frequencies are generated by two metallic structures inserted within the slot. All the three resonant frequencies are independent of each other. Moreover, to achieve better gain, a triple band artificial magnetic conductor (AMC) is designed and placed at a certain distance below the antenna structure. The AMC shows zero reflection phase at all the three resonating frequencies of the antenna. A detailed analysis of the AMC is presented. Significant improvement in gain is obtained at all the three resonating frequencies. Radiation patterns of the antenna are stable with considerably low cross polarization in both E and H planes in all the three frequencies. A prototype of the triple band antenna with AMC is fabricated and the measured results are in good agreement with the simulated results.