Design of Modified U-Slot Multiband Circular Patch Antenna with Cylindrical Dielectric Resonator Antenna

Due to the advancement in the field of wireless communication single antenna operating in multiband frequency are required for wireless applications. In this paper a single circular patch antenna is designed by introducing a modified U- slot to operate at multiple frequencies i.e. 3.5GHz, 5GHz and 6.5GHz. The Slots are incorporated into the patch so that the antenna has its applications in WLAN, Extended WiMAX and International Mobile Communication Systems. However, the major drawback of the microstrip patch antenna is its low gain. To improve the gain a Cylindrical Dielectric Resonator Antenna (CDRA) is placed above multiband antenna. The CDRA is designed with Polypropylene material with dielectric constant 2.2, the radius of CDRA is 1.6cm, with height 9cm. The Modified U-Slot Multiband Circular Patch Antenna with cylindrical Dielectric Resonator Antenna has improved the gain, while maintaining the required return loss at its operating frequency. The structures are simulated using EM Flow solver HFSS and the fabricated structures are measured in anechoic chamber. There is very close agreement with these results.