Abstract: A method of controlling sidelobe distribution in an active electronically steered array, including electronically reshaping the array aperture so as to reduce sidelobes over a selected region of a coverage volume of the array. In one example, reshaping of the aperture is achieved by electronically turning on and/or off selected radiators in the array to vary the angle of edge discontinuities of the aperture, and thereby move the main sidelobes off the principal plane(s) of operation of the array.

Abstract: Described is a mobile radar system which provides both persistent surveillance and tracking of objects with adaptive measurement rates for both maneuvering and non-maneuvering objects. The mobile radar system includes a vehicle having mounted therein an active, electronically-steerable, phased array radar system movable between a stowed position and a deployed position and wherein the phased array radar system is operational in both the deployed and stored positions and also while the vehicle is either stationary or moving. Thus, the mobile radar system described herein provides for longer time on target and longer integration times, increased radar sensitivity and improved Doppler resolution and clutter rejection. This results in a highly mobile radar system appropriate for use in a battlefield environment and which supports single-integrated-air-picture metrics including but not limited to track purity, track completeness, and track continuity and thus improved radar performance in a battlefield.

Abstract: A feed network for an antenna subarray includes a first feed arrangement having an sum output, a second feed arrangement having an delta output, a fixed attenuator having a first port and a second port, the first port connected to the delta output of the second feed arrangement, a first power divider/combiner having a first and second port and a third port; the first port connected to the second port of the fixed attenuator, a variable phase shifter having a first port and a second port, the first port connected to the second port of the power divider/combiner, a variable attenuator having a first port and a second port, the first port connected to the second port of the variable phase shifter, a second power divider/combiner having a first and second port and a third port; the first port connected to the second port of the fixed attenuator, a first circulator having a first port, a second port and a third port, the first port connected to the sum output of the first feed arrangement, and a third power divide

Abstract: Methods and apparatus for an electrically steered array including a phased array aperture having a plurality of elements at a selected spacing, the aperture to provide up to four simultaneous, independent beam sets, wherein the elements are controlled by a single complex weight.

Abstract: Embodiments of the present apparatus and system are directed to a compact satellite communications on the move (SOTM) antenna system that maintains a communications link with a hybrid combination of mechanical and electronic beam steering. This hybrid system ensures that the antenna beamwidth in the plane of the geosynchronous satellites remains within internationally agreed to limits, independent of the location of the satellite with respect to the ground terminal. Systems constructed according to the principles presently disclosed also provide reduced antenna sidelobes in the satellite plane and minimize the electronic scan loss while simultaneously achieving controllable beamwidth, full field of view coverage, and low antenna height.

Abstract: Method and apparatus for a receive electronically steered array aperture including a plurality of radiators each having a single complex phase/amplitude control at a radiating phase center of the radiators to simultaneously receive up to four circularly polarized plane waves, each of the plane waves being arbitrarily of left hand circular polarization or right hand circular polarization, from spatially diverse sources.

Abstract: Described is a mobile radar system which provides both persistent surveillance and tracking of objects with adaptive measurement rates for both maneuvering and non-maneuvering objects. The mobile radar system includes a vehicle having mounted therein an active, electronically-steerable, phased array radar system movable between a stowed position and a deployed position and wherein the phased array radar system is operational in both the deployed and stored positions and also while the vehicle is either stationary or moving. Thus, the mobile radar system described herein provides for longer time on target and longer integration times, increased radar sensitivity and improved Doppler resolution and clutter rejection. This results in a highly mobile radar system appropriate for use in a battlefield environment and which supports single-integrated-air-picture metrics including but not limited to track purity, track completeness, and track continuity and thus improved radar performance in a battlefield.

Abstract: A method of controlling sidelobe distribution in an active electronically steered array, including electronically reshaping the array aperture so as to reduce sidelobes over a selected region of a coverage volume of the array. In one example, reshaping of the aperture is achieved by electronically turning on and/or off selected radiators in the array to vary the angle of edge discontinuities of the aperture, and thereby move the main sidelobes off the principal plane(s) of operation of the array.

Abstract: A motion compensation method and system is included in a radar antenna system mounted on a moving platform which is subject to pitch, yaw and roll. The radar antenna system includes a main array antenna, and an auxiliary antenna. The auxiliary channel associated with the auxiliary antenna utilizes roll, pitch and yaw angle motion compensations as its auxiliary antenna always steers a horizontal fan shape beam at the horizon to blank any surface (land or sea) based EM interferences. Such motion compensations are provided by a ship motion compensator component and process included within the antenna system. The ship motion compensator component in response to platform motion signals indicative of changes in platform motion angles generates new sets of values using an initial set of weighting coefficient values as a function of such angle motion changes.

Abstract: A motion compensation method and system is included in a radar antenna system mounted on a moving platform which is subject to pitch, yaw and roll. The radar antenna system includes a main array antenna, and an auxiliary antenna. The auxiliary channel associated with the auxiliary antenna utilizes roll, pitch and yaw angle motion compensations as its auxiliary antenna always steers a horizontal fan shape beam at the horizon to blank any surface (land or sea) based EM interferences. Such motion compensations are provided by a ship motion compensator component and process included within the antenna system. The ship motion compensator component in response to platform motion signals indicative of changes in platform motion angles generates new sets of values using an initial set of weighting coefficient values as a function of such angle motion changes.

Abstract: A feed network for an antenna subarray includes a first feed arrangement having an sum output, a second feed arrangement having an delta output, a fixed attenuator having a first port and a second port, the first port connected to the delta output of the second feed arrangement, a first power divider/combiner having a first and second port and a third port; the first port connected to the second port of the fixed attenuator, a variable phase shifter having a first port and a second port, the first port connected to the second port of the power divider/combiner, a variable attenuator having a first port and a second port, the first port connected to the second port of the variable phase shifter, a second power divider/combiner having a first and second port and a third port; the first port connected to the second port of the fixed attenuator, a first circulator having a first port, a second port and a third port, the first port connected to the sum output of the first feed arrangement, and a third power divide

Abstract: Method and apparatus for a receive electronically steered array aperture including a plurality of radiators each having a single complex phase/amplitude control at a radiating phase center of the radiators to simultaneously receive up to four circularly polarized plane waves, each of the plane waves being arbitrarily of left hand circular polarization or right hand circular polarization, from spatially diverse sources.

Abstract: Methods and apparatus for an electrically steered array including a phased array aperture having a plurality of elements at a selected spacing, the aperture to provide up to four simultaneous, independent beam sets, wherein the elements are controlled by a single complex weight.

Abstract: A method includes providing a single crystal wafer having MMIC chips. Each chip has an active device in a first surface portion of a semiconductor substrate provided by the wafer and an electrical interconnect having a first portion disposed on a second surface of the semiconductor substrate. The semiconductor substrate structure has a via therethrough, a second portion of the electrical interconnect passing though the via and being electrically connected to the active device. A multilayer interconnect structure is formed on the wafer providing a signal routing section on the second surface portion of a corresponding one of the chips. Each section has dielectric layers and an electrical conductor, such electrical conductor being electrically coupled to the active device to route an electrical signal to such active device. Each chip and the corresponding signal routing section are separated from the wafer.

Abstract: Estimating an angle-of-arrival of a signal includes receiving a signal sent from an emitter. The signal is received at a singly polarized antenna system associated with an antenna response model. An autocorrelation matrix having noise-related eigenvectors is generated in response to the signal. Polarization ratios are determined from projections of a noise-related eigenvector onto the antenna response model. A minimum polarization ratio variance is established for the polarization ratios. A polarization vector corresponding to the minimum polarization ratio variance is identified. An angle-of-arrival of the signal is estimated in accordance with the identified polarization vector.

Abstract: A transceiver having a transmit/receive switch. The transmit/receive switch includes: a common port adapted for coupling to an antenna element; a transmit port; a receive port and a matched port. The transceiver includes a second switch. The second switch has: a common port adapted for coupling to an input/output port through a gain/phase control unit; a transmit port; a receive port and a matched port. The transceiver includes a balanced amplifier. The balanced amplifier includes a pair of input ports. A first one of the pair of input ports is coupled to receive port of the transmit/receive switch, and a second one of the pair of input ports is coupled to the transmit port of the second switch. The balanced amplifier includes a pair of output ports. A first one of the pair of output ports is coupled to the transmit port of the transmit/receive switch and a second one of the pair of ports is coupled to the receive port of the second switch.

Abstract: Calibrating an antenna includes receiving a signal sent from a reference located within a region. The signal has a polarization within an expected polarization range. Polarization value sets are established in accordance with the expected polarization range. Polarization ratios are generated from the plurality of polarization value sets. A minimum polarization ratio variance for the plurality of polarization ratios is established. A polarization value set corresponding to the minimum polarization ratio variance is identified. A calibration correction is determined in accordance with the identified polarization value set.

Abstract: Estimating an antenna pointing error includes receiving a signal sent from a reference located within a region. A polarization ratio is evaluated over the region. A minimum polarization ratio variance for the polarization ratio is established. A location corresponding to the minimum polarization ratio variance is identified. An antenna pointing error is estimated from the identified location.

Abstract: A transceiver having a transmit/receive switch. The transmit/receive switch includes: a common port adapted for coupling to an antenna element; a transmit port; a receive port and a matched port. The transceiver includes a second switch. The second switch has: a common port adapted for coupling to an input/output port through a gain/phase control unit; a transmit port; a receive port and a matched port. The transceiver includes a balanced amplifier. The balanced amplifier includes a pair of input ports. A first one of the pair of input ports is coupled to receive port of the transmit/receive switch, and a second one of the pair of input ports is coupled to the transmit port of the second switch. The balanced amplifier includes a pair of output ports. A first one of the pair of output ports is coupled to the transmit port of the transmit/receive switch and a second one of the pair of ports is coupled to the receive port of the second switch.

Abstract: A technique is described which makes novel use of monopulse data to augment the normal CFAR detection processing by incorporating monopulse data in a computationally simple way into the detection decision process such that off-axis signals which are of sufficient strength to pass a CFAR detection threshold are effectively rejected by a second detection threshold. The signal compared to the second detection threshold is formed from all of the monopulse channels. Detection processing is thus a two step process, incorporating not only the information contained in the magnitude of the Sum channel, but information contained in all of the monopulse channels.