Abstract: A high-throughput communications channel is encoded using transmit waveforms which satisfy a variety of technical constraints deemed desirable for effective radar operations and signal processing. This enables new cooperative spectrum sharing modalities for radar and communications systems.

Abstract: A high-throughput communications channel is encoded using transmit waveforms which satisfy a variety of technical constraints deemed desirable for effective radar operations and signal processing. This enables new cooperative spectrum sharing modalities for radar and communications systems.

Abstract: An iterative clutter calibration method comprises measuring an average of a sidelobe power in a range-Doppler image for a plurality of ranges. A determined value of an objective function is responsive to an average of the sidelobe clutter power. A plurality of beamformer weights is modified and the step of determining the value of the objective function is repeated until a maximum value of the objective function is determined. Each beamformer weight determines a gain and phase of a respective antenna element in an antenna system.

Abstract: Described is a method of modifying an antenna pattern for a phased array antenna having at least one failed antenna element. A number of proximate beamformers in a proximate angular region about a beamformer at an angle of interest are determined. Each of the proximate beamformers has a proximate beamformer weight vector. A corrected beamformer weight vector is determined for the angle of interest as a linear combination of the proximate beamformer weight vectors. Each element of the corrected beamformer weight vector that corresponds to one of the failed antenna elements has a value of zero. The method enables computation of low spatial sidelobe antenna patterns without requiring a recalibration of the antenna thereby enabling uninterrupted operation of systems that employ phased array antennas. The method can also be used to control taper loss or sidelobe level for phased array antennas that have no failed antenna elements.

Abstract: An iterative clutter calibration method comprises measuring an average of a sidelobe power in a range-Doppler image for a plurality of ranges. A determined value of an objective function is responsive to an average of the sidelobe clutter power. A plurality of beamformer weights is modified and the step of determining the value of the objective function is repeated until a maximum value of the objective function is determined. Each beamformer weight determines a gain and phase of a respective antenna element in an antenna system.

Abstract: Described is a method of modifying an antenna pattern for a phased array antenna having at least one failed antenna element. A number of proximate beamformers in a proximate angular region about a beamformer at an angle of interest are determined. Each of the proximate beamformers has a proximate beamformer weight vector. A corrected beamformer weight vector is determined for the angle of interest as a linear combination of the proximate beamformer weight vectors. Each element of the corrected beamformer weight vector that corresponds to one of the failed antenna elements has a value of zero. The method enables computation of low spatial sidelobe antenna patterns without requiring a recalibration of the antenna thereby enabling uninterrupted operation of systems that employ phased array antennas. The method can also be used to control taper loss or sidelobe level for phased array antennas that have no failed antenna elements.