A review on analysis and design of high-gain patch antenna under high-order-mode operation

Abstract

Compared with the fundamental-mode patch antennas, high-order-mode patch antennas inherently possess much larger radiating size, so they are good candidates for high-gain radiation. However, these antennas usually suffer from several drawbacks, such as high sidelobe level, narrow bandwidth and so on. This paper analyzes three reported techniques for sidelobe suppression of the high-order-mode patch antennas, such as high dielectric constant substrate, filed superposition from parasitic patch, and slot loading on patch. As for bandwidth enhancement, dual-band and wideband high-order-mode patch antennas proposed in recent years are reviewed in detail, and it is demonstrated that the multi-mode technique and filtering antenna theory are effective for wideband design. Finally, the design challenges for future high-order-mode patch antennas in terms of narrow impedance bandwidth and antenna adjacent mode suppression are discussed.