A MW and MMW Shared-Aperture Antenna by Reusing Electromagnetic Band-Gap Structure

A dual-band shared aperture antenna is proposed in this letter, based on the concept of electromagnetic band-gap (EBG) decoupling structure reuse, with two antennas separately operating from 4.8 GHz to 5 GHz and 28.5 GHz to 31.5 GHz. By properly adjusting the EBG dimension, the mutual coupling among two symmetrical planar inverted-F antenna (PIFA) elements operating in the microwave (MW) frequency band can be effectively reduced. Simultaneously, the EBG structure itself plays the role of millimeter-wave (MMW) antenna array, which realizing both excellent radiation performance and beam scanning ability with the help of MW antenna. The mutual coupling level of the E-coupled MW two-element antenna is decreased from -8.7 dB to -24.8 dB, and the MMW arrays can steer the beams from -30° to +30°.