Dual-Band Monopole Antenna Using Substrate-Integrated Suspended Line Technology for WLAN Application

In this letter, a substrate-integrated suspended line high-efficiency monopole antenna designed for 2.4/5.2 GHz wireless local area network (WLAN) application is proposed. The proposed antenna is composed of five stacked substrate layers with two embedded air cavities. Compared with the conventional monopole antennas, more metal surfaces of the proposed antenna can be used for radiation and impedance matching, which provides more flexibility for multiband antenna design. By utilizing the embedded air cavities, the loss of the whole structure is significantly decreased, thus efficiency of higher than 95% is achieved. Moreover, the stable omnidirectional radiation patterns are obtained in the two operating frequency bands of 2.25-2.90 and 4.95-5.94 GHz, which cover corresponding WLAN operation frequency bands.