A circularly polarized connected-slot antenna configured to receive radiation at global navigation satellite system, GNSS, frequencies, comprising: a dielectric substrate; a circular patch overlying the dielectric substrate; and a first conductive ring surrounding the circular patch and overlying the dielectric substrate, the first conductive ring separated from the circular patch by a first connected slot; characterized by at least four impedance transformers overlying the dielectric substrate, each of the at least four impedance transformers including a microstrip and a ground pad that are separated by a first dielectric, each microstrip coupled to a first feed from a coaxial cable at an input and coupled to the circular patch at an output, and each ground pad coupled to a ground from the coaxial cable and coupled to the first conductive ring, wherein the output associated with each microstrip is spaced from adjacent outputs associated with other microstrips by approximately equal angular intervals; and a metamaterial ground plane comprising: a plurality of conductive patches arranged along a first plane and separated from the circular patch, the first conductive ring, and the at least four impedance transformers by at least the dielectric substrate, each conductive patch separated from others of the conductive patches; a ground plane arranged along a second plane, the ground plane electrically coupled to at least a first portion of the plurality of conductive patches; and a conductive fence extending at least from the first plane to the second plane and extending around a perimeter of the plurality of conductive patches and around a perimeter of the ground plane, wherein one or more of the plurality of conductive patches, the ground plane, and the conductive fence are coupled to ground. a dielectric substrate; a circular patch overlying the dielectric substrate; and a first conductive ring surrounding the circular patch and overlying the dielectric substrate, the first conductive ring separated from the circular patch by a first connected slot; characterized by at least four impedance transformers overlying the dielectric substrate, each of the at least four impedance transformers including a microstrip and a ground pad that are separated by a first dielectric, each microstrip coupled to a first feed from a coaxial cable at an input and coupled to the circular patch at an output, and each ground pad coupled to a ground from the coaxial cable and coupled to the first conductive ring, wherein the output associated with each microstrip is spaced from adjacent outputs associated with other microstrips by approximately equal angular intervals; and a metamaterial ground plane comprising: a plurality of conductive patches arranged along a first plane and separated from the circular patch, the first conductive ring, and the at least four impedance transformers by at least the dielectric substrate, each conductive patch separated from others of the conductive patches; a ground plane arranged along a second plane, the ground plane electrically coupled to at least a first portion of the plurality of conductive patches; and a conductive fence extending at least from the first plane to the second plane and extending around a perimeter of the plurality of conductive patches and around a perimeter of the ground plane, wherein one or more of the plurality of conductive patches, the ground plane, and the conductive fence are coupled to ground. a plurality of conductive patches arranged along a first plane and separated from the circular patch, the first conductive ring, and the at least four impedance transformers by at least the dielectric substrate, each conductive patch separated from others of the conductive patches; a ground plane arranged along a second plane, the ground plane electrically coupled to at least a first portion of the plurality of conductive patches; and a conductive fence extending at least from the first plane to the second plane and extending around a perimeter of the plurality of conductive patches and around a perimeter of the ground plane, wherein one or more of the plurality of conductive patches, the ground plane, and the conductive fence are coupled to ground.