Abstract: An apparatus for satellite communication may include a reflector configured to redirect electromagnetic energy. Each of multiple feeds may be positioned at a predetermined location with respect to the reflector. A feed-switching mechanism may be configured to selectively activate for use at least one of the multiple feeds. A steering mechanism may be configured to steer the reflector such that a focal point of the reflector approximately coincides with a position of an activated feed of the multiple feeds. The reflector may be mechanically independent of the plurality of feeds and the feed-switching mechanism.

Abstract: A compact photonic radio frequency front end receiver system including a laser chip source, radio frequency and LO inputs, an optical modulator chip coupled to the laser source and the radio frequency and LO inputs, a millimeter scale optical radio frequency multi-pole filter coupled to the optical modulator, an optical switch array chip coupled to the optical radio frequency multi-pole filter, and a detector chip coupled to the optical switch array, all with micro-optic coupling, heterodyne signal recovery, and wavelength locking.

Abstract: In determining an angle for a phase modulation scheme, a key is generated from a prescribed set of bits contained in a symbol. The symbols have an in-phase (I) data word and a quadrature phase (Q) data word that identify coordinates of the symbols in a complex number plane. An angle is retrieved from a memory table from a storage location identified by the key. Each angle in the memory table is established in accordance with constraints under which the memory table was populated so as to be mapped to a phase angle identifying other coordinates in the complex number plane that are within a specified neighborhood about the coordinates of each of the symbols. A signal is generated to convey the symbols as phase differentials at each sample time between a reference phase and the phase angle.

Abstract: A dual rate transmitter may include a modulator circuit configured to modulate orthogonal signals to generate a quadrature modulated signal. An amplifier may be configured to amplify the quadrature modulated signal to produce an amplified signal. A quadrature partial response (QPR) filter may be configured to process the amplified signal to generate an output signal. The QPR filter may allow for full rate QPR and half rate QPSK operation of the transmitter device. The output signal may be transmitted via an antenna. This transmitter approach provides a bandwidth efficiency improvement, as the QPR signal may be operated at twice the rate within the same bandwidth as the quadrature modulated signal using a common saturated transmitter implementation, reducing quantity of components and the resulting mass and cost reduction for a space transmitter solution. Additionally, this approach of using QPR signaling provides greater power efficiency.

Abstract: An apparatus for satellite communication may include a reflector configured to redirect electromagnetic energy. Each of multiple feeds may be positioned at a predetermined location with respect to the reflector. A feed-switching mechanism may be configured to selectively activate for use at least one of the multiple feeds. A steering mechanism may be configured to steer the reflector such that a focal point of the reflector approximately coincides with a position of an activated feed of the multiple feeds. The reflector may be mechanically independent of the plurality of feeds and the feed-switching mechanism.

Abstract: A antenna system for generating and distributing power among a plurality of non-focused beams is provided The system comprises a reflector having a focal plane and a non-parabolic curvature configured to form the defocused beams. The curvature is configured to create a symmetrical quadratic phase-front in an aperture plane of the reflector. The system further comprises a plurality of feed antennas disposed in the focal plane of the reflector and configured to illuminate the reflector. Each feed antenna is configured to contribute power toward each of the defocused beams. The system further comprises a plurality of fixed-amplitude amplifiers, at least one of which corresponds to each feed antenna.

Abstract: A method of fabricating a solid state power amplifier (SSPA) having variable output power is provided. The method includes coupling a first transistor device to a second transistor device and biasing a drain input of each of the first and second transistor device. Further, the method includes biasing a gate input of each of the first and second transistor device varying a drain to source current of each of the first and second transistor device to enable the SSPA to maintain high power added efficiency (PAE) and consistent linearity over a range of output power levels.

Abstract: A radio frequency (RF) communication device may include an RF 90-degree hybrid combiner having stable phase and loss characteristics over greater than one octave of bandwidth, while providing a high degree of isolation between input and isolated port. The structure may include a first element and a second element. The first element includes a first port, a first section for phasing matching, a second section for conductive-layer inversion, a third section for phase-matching section, and a third port. The second element includes a fourth port, a fourth section for phasing matching, a fifth section for conductive-layer inversion, a sixth section for phase-matching, and a second port. In one example, the second and fifth sections are utilized for signal coupling. In another example, the first, third, fourth, and sixth sections are utilized for signal coupling. Different ports may have matched phase differences.

Abstract: A antenna system for generating and distributing power among a plurality of non-focused beams is provided The system comprises a reflector having a focal plane and a non-parabolic curvature configured to form the defocused beams. The curvature is configured to create a symmetrical quadratic phase-front in an aperture plane of the reflector. The system further comprises a plurality of feed antennas disposed in the focal plane of the reflector and configured to illuminate the reflector. Each feed antenna is configured to contribute power toward each of the defocused beams. The system further comprises a plurality of fixed-amplitude amplifiers, at least one of which corresponds to each feed antenna.

Abstract: A true time delay (“TTD”) system with wideband passive amplitude compensation is provided. The TTD system includes an input switch, an output switch, a reference delay line disposed between the input switch and the output switch, and time delay lines disposed between the input switch and the output switch. Each time delay line (“TDL”) has a different line length, and includes a center conductor between two corresponding ground planes. Each center conductor has a width and is separated from the two corresponding ground planes by a gap space. For each TDL, the width of the center conductor is configured such that a loss of the TDL is substantially the same as a loss of every other TDL over a range of operating frequencies. For each TDL, the gap space is configured such that an impedance of the TDL is substantially the same as an impedance of every other TDL.

Abstract: An illuminating-reflector system is provided for transmitting a frequency band in an dispersed beam and a substantially collimated beam. The system includes a secondary reflector configured to transmit a first portion of the frequency band to form the dispersed beam and to reflect a second portion of the frequency band; and a primary reflector configured to receive the second portion of the frequency band reflected from the secondary reflector and to reflect the second portion of the frequency band to form the substantially collimated beam.

Abstract: An illuminating reflector system is provided for transmitting first and second frequency bands for satellite and terrestrial communications. The illuminating reflector includes a first reflector configured to transmit a first portion of the first frequency band in an dispersed beam, to reflect a second portion of the first frequency band, and to transmit the second frequency band; a second reflector configured to reflect the second frequency band received from the first reflector; and a primary reflector configured to receive the second portion of the first frequency band reflected from the first reflector, to receive the second frequency band reflected from the second reflector, and to reflect the second portion of the first frequency band and the second frequency band in a substantially collimated beam.