Artificial Magnetic Conductors on Wideband Patch Antenna

The use of Artificial Magnetic Conductor (AMC) as a reflector in a printed antenna is known to improve the antenna's radiation characteristics. This work investigates the implementation of AMC as a reflector on a wideband planar monopole antenna. The investigation is confined to a basic square unit cell of AMC with four possible variations. The AMC structures are constructed with square cells which have either similar square cells or a Perfect Electric Conductor (PEC) as the back plane. These same structures are also fabricated with vias. The impedance bandwidth, gain and power pattern are simulated and measured over the measured -10 dB impedance bandwidth of 3 GHz to 10 GHz. The outcome of the investigation is that, for the antenna element and AMC structures considered in this study, a gain enhancement of up to 6 dB can be achieved with the AMC structures. In addition, introduction of vias is observed not to influence gain, though it improves cross-polarization levels by 3 dB to 5 dB for AMC constructed of squares backed by PEC.