Abstract: An electromagnetic band gap checkerboard surface including a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant. The first and third quadrants each include a multiplicity of first dual-band electromagnetic band gap structures having a first resonant frequency and a second resonant frequency. The second and fourth quadrants each include a multiplicity of second dual-band electromagnetic band gap structure having a third resonant frequency and a fourth resonant frequency. The first quadrant is directly adjacent to the second quadrant and the fourth quadrant; the third quadrant is directly adjacent to the second quadrant and the fourth quadrant; the first quadrant and the third quadrant are diagonally juxtaposed; and the second quadrant and the fourth quadrant are diagonally juxtaposed.

Abstract: Antenna structure with a curvilinear radiating element and a circularly symmetric high impedance surface ground plane. The curvilinear radiating element has a first diameter in a plane of the curvilinear radiating element and the circularly symmetric high impedance surface ground plane has a second diameter in a plane of the circularly symmetric high impedance surface ground plane. The curvilinear radiating element is positioned proximate the circularly symmetric high impedance surface ground plane with the plane of the curvilinear radiating element parallel to the plane of the circularly symmetric high impedance surface ground plane. A surface of the curvilinear radiating element is separated from a surface of the circularly symmetric high impedance surface ground plane by a distance.

Abstract: An electromagnetic band gap checkerboard surface including a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant. The first and third quadrants each include a multiplicity of first dual-band electromagnetic band gap structures having a first resonant frequency and a second resonant frequency. The second and fourth quadrants each include a multiplicity of second dual-band electromagnetic band gap structure having a third resonant frequency and a fourth resonant frequency. The first quadrant is directly adjacent to the second quadrant and the fourth quadrant; the third quadrant is directly adjacent to the second quadrant and the fourth quadrant; the first quadrant and the third quadrant are diagonally juxtaposed; and the second quadrant and the fourth quadrant are diagonally juxtaposed.

Abstract: Antenna structure with a curvilinear radiating element and a circularly symmetric high impedance surface ground plane. The curvilinear radiating element has a first diameter in a plane of the curvilinear radiating element and the circularly symmetric high impedance surface ground plane has a second diameter in a plane of the circularly symmetric high impedance surface ground plane. The curvilinear radiating element is positioned proximate the circularly symmetric high impedance surface ground plane with the plane of the curvilinear radiating element parallel to the plane of the circularly symmetric high impedance surface ground plane. A surface of the curvilinear radiating element is separated from a surface of the circularly symmetric high impedance surface ground plane by a distance.