Abstract: Provided herein are various improvements to antenna stabilization systems, such as employed on confocal phased array reflector antenna arrangements. In one example, a system includes a feed structure for a main reflector, the feed structure comprising an electronically scanned array (ESA) feed and a sub-reflector. The sub-reflector is configured to propagate a signal between the ESA feed and the main reflector. The system also includes a star tracker element coupled to the feed structure and configured to determine orientation information relative to star alignment, and laser distancing elements coupled to the feed structure and configured to determine distance measurements relative to the main reflector. A control system is configured to determine pointing errors of the main reflector based at least on the orientation information and the distance measurements, and these pointing errors can be used by the ESA feed to adjust steering of a signal towards a target.

Abstract: A Reconfigurable, Flexible Multi-User (RFMU) electronically steered antenna (ESA) includes a top panel and a number of side panels that enable many contacts simultaneously with varying gain requirements from a single, in situ, installation. The top panel includes multiple subarrays and can communicate with flyover satellites, and the side panels can communicate with satellites flying past a side of the ESA. The top panel and the side panels can achieve a beam steering that covers a full or partial, variable gain, hemispheric field-of-view (FoV). The RFMU ESA terminal top and side panels are scalable using flexible modular building blocks. This enables increased contacts, increased gain or a combination thereof sized to meet desired performance.

Abstract: A multisegment array-fed reflector antenna includes a feed array consisting of a number of subarrays and a multisegment reflector to reflect multiple beams of the feed array into a number of elevation angles. A support structure couples the multisegment reflector to the feed array. The multisegment reflector includes two or more ring-focus parabolic segments, and each ring-focus parabolic segment is a parabolic surface extending along a circle around the support structure.

Abstract: A multisegment array-fed reflector antenna includes a feed array consisting of a number of subarrays and a multisegment reflector to reflect multiple beams of the feed array into a number of elevation angles. A support structure couples the multisegment reflector to the feed array. The multisegment reflector includes two or more ring-focus parabolic segments, and each ring-focus parabolic segment is a parabolic surface extending along a circle around the support structure.

Abstract: A multisegment array-fed reflector antenna includes a feed array consisting of a number of subarrays and a multisegment reflector to reflect multiple beams of the feed array into a number of elevation angles. A support structure couples the multisegment reflector to the feed array. The multisegment reflector includes two or more ring-focus parabolic segments, and each ring-focus parabolic segment is a parabolic surface extending along a circle around the support structure.

Abstract: A Reconfigurable, Flexible Multi-User (RFMU) electronically steered antenna (ESA) includes a top panel and a number of side panels that enable many contacts simultaneously with varying gain requirements from a single, in situ, installation. The top panel includes multiple subarrays and can communicate with flyover satellites, and the side panels can communicate with satellites flying past a side of the ESA. The top panel and the side panels can achieve a beam steering that covers a full or partial, variable gain, hemispheric field-of-view (FoV). The RFMU ESA terminal top and side panels are scalable using flexible modular building blocks. This enables increased contacts, increased gain or a combination thereof sized to meet desired performance.

Abstract: A high data rate distribution network for low-earth orbit (LEO) satellite constellations is described. The high data rate distribution network includes multiple LEO constellations, each constellation including a number of LEO spacecraft orbiting in a LEO plane that are all connected together by by-directional free space optical links. The distribution network further includes geostationary earth orbit (GEO) spacecraft in communication with a number of ground gateways. The GEO spacecraft can receive forward communication traffic including radio-frequency (RF) and/or optical data streams uplinked from the ground gateways and can convert the received forward communication traffic into a forward aggregated traffic. The GEO spacecraft can further optically downlink the forward aggregated traffic to LEO spacecraft in a LEO constellation that is in line of sight of the GEO spacecraft. The forward aggregated traffic is then disaggregated among and received by the LEO spacecraft in the LEO constellation.

Abstract: A hybrid electronic/mechanical scanning array antenna including an outer housing and a cold plate rotatable therein. A waveguide aperture including an array of antenna elements is mounted to a top surface of the cold plate and a multi-layer circuit board is mounted to a bottom surface of the cold plate. A plurality of amplifier modules are mounted to the cold plate, where the circuit board includes a plurality of openings that allow the amplifier modules to be directly mounted to the cold plate, and the cold plate includes a plurality of RF signal channels that allow RF signals from the amplifier modules to travel through the cold plate. The amplifier modules are controlled to provide phase-weighting for electronic signal scanning in an elevation direction and rotation of the cold plate allows signal scanning in an azimuth direction.

Abstract: A hybrid electronic/mechanical scanning array antenna including an outer housing and a cold plate rotatable therein. A waveguide aperture including an array of antenna elements is mounted to a top surface of the cold plate and a multi-layer circuit board is mounted to a bottom surface of the cold plate. A plurality of amplifier modules are mounted to the cold plate, where the circuit board includes a plurality of openings that allow the amplifier modules to be directly mounted to the cold plate, and the cold plate includes a plurality of RF signal channels that allow RF signals from the amplifier modules to travel through the cold plate. The amplifier modules are controlled to provide phase-weighting for electronic signal scanning in an elevation direction and rotation of the cold plate allows signal scanning in an azimuth direction.

Abstract: An apparatus in one example comprises a differential amplifier and a differential mixer. The differential amplifier is configured to receive a multi-octave differential input signal and output an amplified multi-octave differential output signal. The differential amplifier is also configured to substantially reduce second order harmonic distortion of the amplified multi-octave differential output signal through common mode rejection. The differential mixer configured to multiply the amplified multi-octave differential output signal with a local oscillator input signal and output an up-converted sub-octave differential output signal. The multi-octave differential input signal and the up-converted sub-octave differential output signal comprise a substantially same bandwidth.

Abstract: A low-profile, electronically scanned antenna that can scan a hemisphere is comprised of three, phased array radiators. Each radiator face has an azimuth and elevation scan angle equal to 120 degrees. The three radiator faces are arranged in a truncated 3 sided pyramid such that they prove continuous hemispherical coverage. The three radiators are mounted to cooled panels of a truncated pyramid-shaped frame such that the radiators enable a full hemisphere to be scanned by radar.

Abstract: An apparatus in one example comprises a differential amplifier and a differential mixer. The differential amplifier is configured to receive a multi-octave differential input signal and output an amplified multi-octave differential output signal. The differential amplifier is also configured to substantially reduce second order harmonic distortion of the amplified multi-octave differential output signal through common mode rejection. The differential mixer configured to multiply the amplified multi-octave differential output signal with a local oscillator input signal and output an up-converted sub-octave differential output signal. The multi-octave differential input signal and the up-converted sub-octave differential output signal comprise a substantially same bandwidth.

Abstract: Methods and apparatus are provided for determining aperture phase distributions for use in radiating signals with an active phased array antenna having multiple beams and multiple carriers. Distinct initial phase distributions corresponding to the carriers are allocated. The initial phase distributions are modified for each of the carriers to generate respective radiation patterns that substantially correspond to respective coverage areas in accordance with amplification and radiation of signals having the initial phase distributions. The modified phase distributions are optimized to simultaneously increase carrier-signal power and reduce an intermodulation product radiated in the respective coverage areas in accordance with amplification and radiation of signals having the modified phase distributions.

Abstract: An automatic network analyzer that measures continuous wave radio microwave driven transfer characteristics of nonlinear devices and simultaneously calculates and displays corresponding noise driven transfer characteristics and noise power ratio data. This automatic network analyzer employs software or firmware that uses closed-form equations to exactly calculate noise parameters. This is done in real-time as CW measurements are taken.

Abstract: A dual polarized horn antenna that increases the efficiency of a square or rectangular aperture which may be used in situations where a high efficiency aperture is needed in a constrained space. The antenna has a body that is tapered from a first end to a second end, wherein the first end is smaller in cross section than the second end. A flange is formed around the periphery of the body adjacent to the first end. An opening is formed in the first end of the body. A tuning iris is preferably disposed in the opening that provides for impedance matching. An insert is disposed in the central tapered opening 16 adjacent to the second end that has a central cross-shaped tapered member. The central cross-shaped tapered member extends into the central tapered opening and forms a plurality waveguide passages that form a corresponding plurality of quadrants. A plurality of cross-shaped members are respectively disposed in the quadrants and extend a short distance into the central tapered opening.