Design of a Thin, Electrically Small, Two-Element Parasitic Array With Circular Polarization

A circularly polarized, electrically small, two-element parasitic array antenna is proposed. Circular polarization is created through the use of a single feed in crossed-dipole array elements. Miniaturization is achieved with a top-loading structure. Multiple folds are implemented to boost the reduced radiation resistance that results from the small size of the antenna and close spacing between the driver and director. The total volume of the antenna is 0.263λ × 0.263λ × 0.030λ, and the electrical size, kr, is 0.84. The realized gain of the antenna in the forward direction is 5.0 dBic at 146 MHz. The axial ratio is less than 3 dB across the entire VHF orbiting satellite carrying amateur radio band (145.8-146 MHz).