Technology is described for a slot antenna. The slot antenna can include a substrate having a metal layer on a first side of the substrate. A feed line can be located on a second side of the substrate. A first polygon shaped slot can be formed in the metal layer of a first side of the substrate. A second polygon shaped slot can also be formed in the metal layer of the first side of the substrate. The second polygon shaped slot can be recessed within a perimeter of the first polygon shaped slot and the second polygon shaped slot and first polygon shaped slot share a common side. Examples of the first and second polygon shapes may include square or diamond shapes.