Abstract: Provided herein are various enhancements for antenna systems and directed radio frequency energy structures. In one example, an apparatus includes an antenna array comprising a plurality of antenna elements formed by waveguide structures embedded within a substrate and positioned about a longitudinal axis of the substrate to form at least two concentric ring arrangements of antenna elements. Apertures of the waveguide structures are configured to emit or receive radio frequency (RF) energy generally along the longitudinal axis. Feed elements are coupled to each of the waveguide structures on an end opposite of the apertures, and configured to couple the RF energy for the antenna array.

Abstract: A reflector antenna includes a reflector having a curved reflecting surface that extends around a longitudinal center axis, wherein the curved reflecting surface is defined by rotating a concave curve around the longitudinal center axis and wherein one end of the concave curve defines an apex on the longitudinal center axis. The reflector antenna may further include a ground plane extension having a flat reflecting surface abutting an edge of the reflector and extending radially away from the longitudinal center axis. A phased array feed may be arranged spaced apart from and opposite to the reflecting surfaces of the reflector and the ground plane extension. A tapered collar may be arranged adjacent to the phased array feed, wherein the tapered collar tapers outward away from the phased array feed and towards the reflector, and wherein the tapered collar comprises an inner reflective surface facing the reflector.

Abstract: Distributed gain equalization circuits for use with radio frequency (RF) devices are provided. The distributed gain equalization circuits include a substrate layer, multiple transverse electromagnetic (TEM) line circuits disposed on the substrate layer and multiple traces disposed on the substrate layer, each trace connected to one or more of the TEM line circuits. The traces and TEM line circuits are configured to provide resistances, inductances and capacitances to eliminate the need for lumped or packaged resistors, inductors and capacitors. The distributed gain equalization circuit operates at millimeter wave frequencies and provides a compensating gain slope to counteract a negative gain slope of the RF device. Methods of manufacturing distributed gain equalization circuits are also provided.

Abstract: An antenna element includes a radiator element, a plurality of feed circuits and a multiplexing interface. The radiator element can transceive radio-frequency (RF) signals. The feed circuits, which include impedance and multiplexing features, are realized on multiple feed locations of the radiating element feed slot. The multiplexing interface is electrically coupled to the plurality of feed circuits and can multiplex a number of sub-band signals associated with the feed circuits. The multiplexing interface can provide a high isolation between the feed circuits.