On the Design of a Multiband Microstrip Patch Antenna by Introducing a Defected Ground Structure

A rectangular inset-fed microstrip patch antenna with a defected ground structure to operate at the 2.4 GHz (ISM band), 5.7 GHz (WLAN band), and 6.9 and 8.5 GHz (WBAN band) is presented here. The antenna was first designed only for the ISM band, and later, the same antenna was improvised by imposing specific defects as various slots in the reference plane of the antenna to use for multiband applications at WLAN and WBAN bands. The proposed model was designed in a full-wave simulation tool and has been verified through measurements of return loss and radiation patterns of a fabricated prototype that showed reasonable agreements between simulated and measured values.