Broad beamwidth circular polarisation antenna: Microstrip-monopole antenna

A novel broad beamwidth circular polarisation antenna called a microstrip-monopole antenna (MMA) is proposed. By loading four cylinders which are perpendicular to the substrate of the microstrip antenna near the edge of a circular patch, broad beamwidth is achieved. Using this simple method, the MMA is invented. The 3 dB beamwidth of the MMA is about 156 at central frequency, which is 110 wider than the classical microstrip antenna. So the MMA is a good candidate as wide-angle scanning phased array. Measured and simulated results are demonstrated and good agreement is obtained.