Abstract: A computer system for angle of arrival estimation receives one or more snapshots from a circular array of antennas. The computer system processes the one or more snapshots for amplitude and/or phase-based direction finding using two cascaded algorithms. The first algorithm of the two cascaded algorithms is configured to identify a target subregion from which a signal arrives. The second algorithm of the two cascaded algorithms is configured to identify a direction of the signal within the target subregion.

Abstract: In various implementations, a quasi-monostatic STAR antenna system comprises a parabolic reflector antenna for transmission (TX) and a receiving (RX) antenna mounted back-to-back with the reflector feed. The physical size of the RX antenna can be comparable to or smaller than that of the TX feed, in order to prevent additional reflector blockage. To increase the system isolation both the TX feed and the RX antenna are CP. In one implementation, for example, to achieve same TX and RX polarization (i.e. no polarization multiplexing) the TX feed is LHCP and the RX antenna is RHCP. The LHCP fields from the TX feed undergo polarization reversal after bouncing back from the reflector. Thereby, the TX and RX operate in the same polarization, as illustrated in FIG. 1.

Abstract: Various implementations of combined antenna are provided. In one implementation, for example, a combined antenna comprises a transverse electromagnetic (TEM) horn antenna element and a loop antenna element coupled to the TEM horn antenna element, wherein the loop antenna element comprises at least one slot disposed in the loop antenna element.

Abstract: In various implementations, designs of relatively simple ultra-wideband STAR front-end systems are provided. For example, such systems may include implementations utilizing a plurality of antenna arms in which a first portion of the arms is configured to transmit and a second portion of the arms is configured to receive. In one implementation, for example, a co-channel simultaneous transmit and receive (STAR) monostatic aperture configuration includes a single-polarized multi-port monostatic co-channel simultaneous transmit and receive (c-STAR) spiral antenna aperture. Other examples are also provided.