Abstract: One embodiment of the invention relates to an antenna system, which comprises an antenna array and a calibration system adapted to calibrate the antenna array. The calibration system can calibrate the antenna array in transmit mode, in receive mode, or in both transmit and receive mode. The antenna array includes a plurality of antenna elements and an antenna beamforming system, and the calibration system includes a plurality of calibration probes integrated with the plurality of antenna elements. The calibration probes may be transmit calibration probes, receive calibration probes, or both. In addition, the calibration system includes a calibration processing system adapted to calibrate the antenna array utilizing the interleaved calibration probes. In one embodiment, the calibration processing systems calibrates the antenna array by performing control circuit encoding (CCE) calibration on the antenna array.

Abstract: A phased array antenna design that is modular and scaleable in terms of beam quantity, coverage area, and receive sensitivity/transmit EIRP.

Abstract: A modular phased array antenna provides a reduction in the error signals that are introduced into beam signals by electromagnetic coupling that is inexpensive and does not cause an increase in weight or in power consumption. A modular phased array antenna has irregular or random connections of beam signals to beam ports of each modular antenna assembly so as to provide improved beam-to-beam isolation. A modular phased array antenna comprises a plurality of modular antenna assemblies, each modular antenna assembly having a plurality of beam ports, each beam port of a modular antenna assembly connected to a different beam signal, wherein the beam signals are irregularly connected to the beam ports relative to the modular antenna assemblies. The beam signals may be randomly connected to the beam ports relative to the modular antenna assemblies.

Abstract: A partially deployed antenna array system that provides many beams per array and also reduces the amount of expensive advanced high density packaging that is required. The beamforming circuitry is located on the spacecraft bus, while the frequency converters, amplifiers, and antenna elements are deployed. The antenna array system for a spacecraft comprises a deployed antenna comprising a plurality of antenna elements operable to transmit or receive a radio frequency signal, a beamformer mounted in the body of the spacecraft operable to process a radio frequency signal or an intermediate frequency signal, and a transmission medium operable to communicate the radio frequency signal or the intermediate frequency signal between the beamformer and the deployed antenna. The transmission medium may comprise a fiber-optic link or alternatively may comprise a coaxial cable. The deployed antenna may comprise a plurality of antenna tiles.

Abstract: A phased array antenna design that is modular and scaleable in terms of beam quantity, coverage area, and receive sensitivity/transmit EIRP.

Abstract: An apparatus, method, and computer program product for assigning communication resources in a beam-hopping cellular communication system. The satellite has a multiple beam antenna that covers a number of cells that is greater than the number of available beams In a preferred embodiment, the method includes the steps of selecting a frequency for each beam, computing a dwell time for each cell based on the traffic estimates for each cell and the number of available beams, and selecting a cell hopping sequence for each beam based on the dwell times and predicted inter-beam interference.

Abstract: The invention relates to a switchable bidirectional phase shift network exhibiting a desired differential insertion phase suitable for use as a phase bit in a multi-bit phase shifter. The design is economical in its use of components--six field effect transistors, three inductors and no capacitors, and provides in one switching state a band pass network of low insertion phase and in the other switching state a low pass network of high insertion phase. The rate of change of insertion phase over a range of operating frequencies is substantially equal for the two states.

Abstract: An electronically reconfigurable digital pad attenuator is disclosed using selectively controlled segmented field effect transistors in a passive, non-gain state as the principal impedance elements. The attenuator may be fabricated in the monolithic microwave integrated circuit (MMIC) format with a segmented gate field effect transistor being connected in each of the separate branches of a Pi pad, Tee pad, or Bridged Tee pad attenuator configuration. The individual FET segments are maintained in a high admittance "ON" state or a low admittance "OFF" state in accordance with the binary control potentials applied to the gate of each segment, the principal electrodes being maintained at a zero potential difference. The attenuation then becomes a function of the binary gate potentials applied to each segment and assumes one of a set of well-defined discrete values. The attenuator consumes minimum power, provides attenuation steps that are independent of GaAs MMIC fabrication process tolerances, i.e.

Abstract: The invention relates to a matching network which may be serially inserted in the path between a transmitter power amplifier and/or a receiver low noise amplifier and an element of a steerable array antenna to compensate for mismatching occurring when the antenna is steered away from bore sight or tuned to off resonant frequencies. The invention permits computer controlled digital setting of the matching network in accordance with the known impedance characteristics of the antenna element, to restore VSWRs which in an exemplary case may have a maximum design value of 3.0 when uncompensated to a VSWR of 1.6 with a simple matching network, or to a VSWR of 1.22 with a more highly corrected matching network.

Abstract: The invention relates to a low noise amplifier for use at microwave frequencies which may be fabricated using integrated circuit techniques. In accordance with the invention, critical components are made adjustable so as to simplify the design process and manufacturability of the amplifier. A two stage low noise amplifier is disclosed in which TEE networks are used as input and output networks in each stage, and in which one element of each TEE includes an adjustable spiral inductor. The value of each adjustable spiral inductor may be adjusted by removal of one or more air bridges disposed along the inner turn of the inductor. This permits one to "tune" the amplifier and optimize its performance.