A Novel Circularly-Polarized Microstrip Antenna by Coupled Resonators

This paper proposes a circularly-polarized (CP) antenna through coupling effects. By orthogonally arranging the short-circuited (open-circuited) ends of two identical λ/4 short-circuited microstrip line (MS-L) resonators to each other, the CP radiation by magnetic(electric) coupling can be produced. Then, for improving the peak gain and the axial ratio bandwidth (ARBW), a binary array comprising of an electrically coupled (EC) pair and a magnetically coupled (MC) pair of resonators is presented. Then the array is fabricated, and an excellent agreement between the experiment and simulation results is validated.