Substrate integrated waveguide cavity-backed dual-polarized multi-band antenna
An antenna is provided that includes a dielectric-filled cavity having a bottom surface, a top surface, and a rectangular perimeter. A round metal layer faces the bottom surface whereas a resonator metal layer faces the top surface. A plurality of metallic vias is arranged about the rectangular perimeter to couple a perimeter of resonator layer to the ground layer. An opening divides the resonator layer into a first pair of resonators and into a second pair of resonators. Within each pair of resonators, one resonator is configured for operation according to a first linear polarization whereas a second resonator is configured for operation according to a second linear polarization that is orthogonal to the first linear polarization.
1. An antenna assembly, comprising:
a dielectric-filled cavity having a bottom surface, a top surface, and a rectangular perimeter having a first side that extends from a first corner to a fourth corner, a second side that extends from the fourth corner to a second corner, a third side that extends from the second corner to a third corner, and a fourth side that extends from the third corner to the first corner, and wherein the first corner is opposite to the second corner and the third corner is opposite to the fourth corner;
a first ground metal layer adjacent the bottom surface;
a resonator metal layer adjacent the top surface;
a plurality of metallic vias disposed along the rectangular perimeter and coupled to the first ground metal layer and to the resonator metal layer; and
an asymmetric x-shaped opening dividing the resonator metal layer into a first right-angled triangular resonator, a second right-angled triangular resonator, a third right-angled triangular resonator, and a fourth right-angled triangular resonator, wherein the first right-angled triangular resonator and the second triangular right-angled resonator are each of a first size that is greater than a second size of each of the third right-angled triangular resonator and the fourth right-angled triangular resonator, and wherein a hypotenuse of the first right-angled triangular extends along the fourth side from a first end aligned with the third corner to a second end that is spaced apart from the first corner by a first distance, and wherein a hypotenuse of the second right-angled triangular resonator extends along the first side from a first end aligned with the fourth corner to a second end that is spaced apart from the first corner by the first distance.
2. The antenna assembly of claim 1 , wherein a hypotenuse of the third right-angled triangular resonator extends along the second side from a first end spaced apart from the second corner by the first distance to a second end spaced apart from the fourth corner by a second distance that is greater than the first distance, and wherein a hypotenuse of the fourth right-angled triangular resonator extends along the third side from a first end spaced apart from the second corner by the first distance to a second end spaced apart from the third corner by the second distance.
3. The antenna assembly of claim 1 , wherein the rectangular perimeter is a square perimeter.
4. The antenna assembly of claim 1 , wherein the first triangular resonator and the third triangular resonator are each configured to radiate according to a first linear polarization, and wherein the second triangular resonator and the fourth triangular resonator are each configured to radiate according to a second linear polarization that is orthogonal to the first linear polarization.
5. The antenna assembly of claim 1 , further comprising:
a second ground metal layer below the first ground metal layer;
a stripline metal layer intervening between the first ground metal layer and the second ground metal layer;
a first probe coupled to the first right-angled triangular resonator and extending through a first opening in the first ground metal layer to the stripline metal layer; and
a second probe coupled to the second right-angled triangular resonator and extending through a second opening in the first ground metal layer to the stripline metal layer, wherein the stripline metal layer is configured into stripline conductors coupled to the first probe and the second probe.
6. The antenna assembly of claim 5 , further comprising:
a substrate coupled to a bottom surface of the second ground metal layer.
7. The antenna assembly of claim 6 , wherein the substrate is a semiconductor substrate.
8. The antenna assembly of claim 6 , wherein the substrate is a circuit board substrate.
9. The antenna assembly of claim 5 , wherein the first probe is capacitively coupled to the first right-angled triangular resonator and wherein the second probe is capacitively coupled to the second right-angled triangular resonator.
10. The antenna assembly of claim 5 , wherein the first probe is directly coupled to the first right-angled triangular resonator and wherein the second probe is directly coupled to the second right-angled triangular resonator.
11. The antenna assembly of claim 1 , wherein the antenna assembly is in proximity to an edge of a cellular telephone such that a boresight of the antenna assembly faces out of the edge.