Miniaturized Poincaré Sphere Source Antenna Loaded by a Pair of Lumped Inductors

A miniaturized design of a Poincaré sphere source antenna is proposed. A non-uniform square loop, two lumped inductors, and a diagonally fed dipole launcher compose the antenna. As experimentally verified at 2.45GHz-band, the overall antenna size can be reduced by 35% compared to conventional Poincaré sphere source antennas under a pair of even-modes resonance. The miniaturized prototype shows an impedance bandwidth of 8.2% for reflection coefficient lower than -10dB, and an AR bandwidth of 4.9% smaller than 3dB.