Design and simulation based studies of a dual band u-slot patch antenna for WLAN application

Three different designs of a dual band patch antenna have been investigated in this paper. By using u-slot patch geometry dual band operation has been obtained. The patch antenna has been designed and simulated in CST Microwave Studio. By studying the antenna parametrically, it has been observed in CST Microwave Studio how the antenna characteristics vary with the variation of its different parameters. This observation has provided us sufficient insight to optimize the antenna parameters to meet the design requirements. The proposed designs of the antenna operate in 3.65 GHz band which is common to all three designs but the second operating band is different. By varying the u-slot broadness the second frequency band can be shifted from 5.25 GHz to 5.76 GHz. Moreover, it can be brought to 2.45 GHz band by carefully adjusting the parameters of the antenna. The gain and directivity in 3.65 GHz band of one of the three designs have been improved in other two designs. The gain has been improved from 3.73 dB to 6.6 dB and the directivity from 6.44 dBi to 7.55 dBi in 3.65 GHz band. The operating frequencies of the proposed designs fall in IEEE802.11a (5.20 GHz and 5.775 GHz), IEEE802.11b (2.45 GHz) and IEEE802.11y (3.675 GHz) standards which would allow WLAN operation. This patch antenna has been intended to be used in portable devices that demand miniaturized constituent parts.