A Miniaturized Phase Mode Antenna Based on a Radial SSPPs Structure and Its 1-D Linear Arrays

A miniaturized dual-port phase mode antenna (PMA) based on radial spoof surface plasmon polariton (SSPPs) structure with continuous scanning pattern and two kinds of 1-D linear extended arrays of it are proposed. The proposed PMA is composed of a vertical PCB (
$0.28\lambda \times 0.27\lambda $
) printing the SSPPs scatterer and the feeding loop of two isolated ports and a metal ground. Two independent equivalent current vectors are excited on the aperture by the two ports and summed up to be a current with rotating direction, which is controlled by the phase difference between the ports. The rotating current triggers a rotating pattern of the PMA and introduces the continuous phase mode-scanning characteristic of it. The PMA is extended to a wide range 2-D scanning and gain overlapping futures of two 1-D arrays with two directions of arraying based on the generalized principle of pattern multiplication (PPM). A beam scanning range
$- 81^{\circ }\lt \theta _{\mathrm {m}} \lt 81^{\circ }$
(
yoz
) with a peak gain of 12.3 dBi of the
$1\times 4$
2-D scanning array is achieved, and that
$- 77^{\circ }~\lt \theta _{\mathrm {m}} \lt 76^{\circ }$
(
xoz
) of the gain overlaying array with the same scale is realized with a 3.3 dB scanning gain fluctuation. The suppression of first sidelobe and other advantages introduced by the proposed PMA in generalized array are demonstrated.