An axial-ratio beamwidth enhancement of patch antenna with digonal slot and square ring

摘要

A novel circularly polarized (CP) antenna with wide angular coverage is presented. The proposed antenna is formed by a 45 degrees slot cut in the center of a rectangular patch antenna and a square ring around it. It can achieve an impedance bandwidth of 110MHz and a 3dB axial ratio bandwidth of 25MHz. For this design, very stable and symmetrical radiation patterns are obtained. The 3dB axial ratio beamwidth for the antenna is 160 degrees, compared with the antenna that without the metal square ring, the antenna with square ring has 19 degrees more 3dB axial ratio beamwidth. This antenna has been successfully applied on passive keyless entry system on door lock. (c) 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:672-675, 2016