Abstract: A dual-polarization common aperture antenna having fully populated common aperture dual polarized arrays. The inventive antenna includes a first and second arrays of radiating slots disposed in a faceplate. The second array is generally orthogonal and therefor cross-polarized relative to the first array. The first array is waveguide fed and the second array is stripline fed. In the illustrative implementation, the first array and the second array share a common aperture. The common aperture is fully populated and each array uses the aperture in its entirety. The first and second arrays of slots are arranged for four-way symmetry. Each slot in the first array is a vertically oriented, iris-excited shunt slot fed by a rectangular waveguide and centered on a broad wall thereof. The second array is a standing wave array in which each slot is an air cavity backed slot fed by an inverted micro-stripline offset from a center thereof.

Abstract: A programmable interface. The inventive interface is designed to be used with an interface controller and includes a first circuit for selecting one or more components from a plurality of components in response to at least one first control signal. A second circuit selectively connects the components in response to at least one second control signal. A third circuit selects a serial output mode or a parallel output mode of said components in response to at least one third control signal. In an illustrative implementation, the inventive interface is used as part of an IEEE 1149.1 bus architecture and includes a plurality of stages. At least one of the stages is associated with each of the components under test and includes circuitry for selecting an associated component. The second circuit includes circuitry within each stage for selectively connecting an associated component to a second component by outputting the output of an associated component or the output a previous stage as the output of the stage.

Abstract: A first MEM is mounted on a substrate having a first contact and a second contact is mounted on a substrate. A PA power cell is thermally connected to the substrate using a thermal bump. The power cell is electrically insulated from the substrate. The power cell has a first power cell bump and a second power cell bump as pathways for I/O functions. A first insulator is mounted on the substrate supporting a second MEM above the substrate. The second MEM has a first connection and a second connection The first connection and the second connection are located on a bottom surface of the second MEM. A first conductive via vertically traverses the first insulator and is connected to the first connection from the second MEM. This first conductive via is further connected to a first conductor. The first conductor is insulated from substrate by a first insulating layer. The first conductor is further connected to the first power cell bump.

Abstract: A chemical sensing system and method. The system (10) includes a transmitter having a laser for providing a collimated beam of electromagnetic energy at a first frequency and a Q switch in optical alignment with the beam. The system further includes a crystal for shifting the frequency of the beam from the first frequency to a second frequency. A mechanism is included for shifting the beam from the second frequency to a third frequency in the range of 8-12 microns. The system includes a mechanism for switching the polarization state of the second beam and providing third and fourth beams therefrom. The third beam has a first polarization and the fourth beam has a second polarization. The second polarization is orthogonal relative to the first polarization. The frequency shifted third and fourth beams are combined to provide an output beam in the range of 8-12 microns. The output beam is transmitted and a return signal is detected by a receiver in the illustrative chemical sensing application.

Abstract: An integrated module for an active antenna assembly is disclosed. The integrated module is switchable between a receive mode and a transmit mode and includes active components and a dual input wideband balun. The active components includes amplifiers and micro electro-mechanical system (MEMS) switches. The integrated module is adapted for positioning directly behind a radiator of an antenna array.

Abstract: Techniques for maintaining beam pointing for an Electronically Scanned Antenna (ESA) as its frequency is varied over a wide frequency bandwidth. A technique uses discrete phase shifters, a number of stored states, and a control methodology for rapidly switching among the states.

Abstract: An improved sigma-delta modulator is disclosed. The sigma-delta modulator utilizes Micro Electro Mechanical System (MEMS) technology coupled with on-chip LC networks. MEMS switches are used to switch capacitors and inductors in and out of the network to alter the center frequency and tuning range of the sigma-delta modulator, thus eliminating active components in each LC network. Furthermore, the use of MEMS switches improves the Q of each LC network relative to previous on-chip sigma-delta modulator designs. The increased Q of each LC network reduces or eliminates the need for active Q-enhancement circuitry and improves the inherent filter shape within the loop of the sigma-delta modulator. In addition, the distortion of active components with the loop of the sigma-delta modulator also is improved. The addition of a decimator to the chip presents a complete single chip LC sigma-delta analog-to-digital converter.

Abstract: A method is provided for improving edge terminations in a semiconductor device while maintaining breakdown voltage of said semiconductor device at or near its theoretical limit. The method comprises: employing ion-implantation to create a compensated region around the semiconductor device, followed by wet chemical etching to form a mesa on the order of 0.2 to 0.3 &mgr;m. The method provides a simple but novel approach to fabricate edge terminations in semiconductor devices in general and in devices employing p-n junctions such as in a GaAs heterojunction bipolar transistor (HBT) to achieve near-ideal electrical characteristics at the device edge. Instead of traditional edge beveling techniques such as those involving grinding, sandblasting, or mesa-etching using masks, the technique disclosed herein utilizes ion-implantation to create a compensated region around the device and wet chemical etching to make a shallow mesa.

Abstract: A microwave transmitter circuit including a divider series feed signal line, collector series feed signal line, a plurality of parallel solid state amplifier coupler circuits connected between the divider series feed line and the collector series feed line, and phase shifting circuitry distributed along the collector series feed line for compensating phase tracking error between the divider series feed line and the collector series feed line.

Abstract: A microelectromechanical system (MEMS) steerable electronically scanned lens array (ESA) antenna and method of frequency scanning are disclosed. The MEMS ESA antenna includes a MEMS E-plane steerable lens array and a MEMS H-plane steerable linear array. The MEMS E-plane steerable lens array includes first and second arrays of wide band radiating elements, and an array of MEMS E-plane phase shifter modules disposed between the first and second arrays of radiating elements. The MEMS H-plane steerable linear array includes a continuous transverse stub (CTS) feed array and an array of MEMS H-plane phase shifter modules at an input of the CTS feed array. The MEMS H-plane steerable linear array is disposed adjacent the first array of radiating elements of the MEMS E-plane steerable lens array for providing a planar wave front in the near field.

Abstract: Signal processing methods useful in single-antenna multiple-pass interferometric synthetic aperture radars. The signal processing methods compute an initial elevation estimate from the phase difference between a pair of images (A0, A1) with a relatively small elevation angle difference (i.e., a short interferometric baseline) and uses it to initialize the elevation estimation process for pairs of images (A0, A2) with longer interferometric baselines. The method may be used to process images that are coherent, or not necessarily mutually coherent. The outputs of the methods comprise a terrain elevation map that mitigates for atmospheric error and a turbulence map.

Abstract: Differential heating is avoided by a digital to analog converter for generating analog cyclical waveforms having a period. The cyclical waveforms are generated by conversion of a sequence of step wise linearly incrementing digital phase words presented during the period for conversion. The digital to analog converter has a clock for operating conversion timing within the digital to analog converter. The clock generates a clock pulse for conversion of each of the digital phase words by said digital to analog converter while generating the cyclical waveform. A lookup read only memory for converting each of the incrementing digital phase words within the period into a plurality of ON commands to be used by a plurality of current sources. The plurality of ON commands are timed to generate the cyclical waveforms and have nearly equal time duration approximating a 50 percent duty cycle. The cyclical waveform has one or more non-linear portions reflected in the content of the read only memory.

Abstract: A switched loop RF radiator circuit, comprising a radiator element, a RF input/output (I/O) port, and a balun coupled between the radiator element and the (I/O) port. The balun includes a 180° switched loop circuit having transmission line legs coupled to a balun transition to provide a selectable phase shift, and a microelectromechanically machined (MEM) switch Many radiator circuits can be deployed in an electronically scanned antenna array.

Abstract: A system (100) and method for focal plane array calibration using an internal non-uniform calibration source (30). In the illustrative embodiment, the system (100) includes a first mechanism (16) for calculating a relative gain of each detector element in the focal plane array (20) relative to at least one reference element, a second mechanism (17) for obtaining the absolute gain of the reference element, and a third mechanism (18) for calculating the absolute gains for all other detector elements using the relative gains in conjunction with the absolute gain of the reference element. The relative response of each pixel is calculated from measurements of the response of each pixel using an internal calibration source (30) at two or more different source positions, and two illumination intensities at each position. Measurements using a pair of source positions separated by k pixels establishes the relative response of the ith pixel with respect to the (i+k)th pixel.

Abstract: Techniques for converting input data from a multiplicity of sources that are mutually asynchronous, to a single, common synchronous format for local processing by an information processor. Logical operations are described which control first-in-first-out (“FIFO”) buffers to align all inputs to a predetermined point in the data flow or processing sequence, and which maintain clock-by-clock alignment of the input data sequences for an indefinite period of time thereafter.

Abstract: A system and method for efficient phase error correction in range migration algorithm (RMA) for synthetic aperture radar (SAR) systems implemented by making proper shifts for each position dependent phase history so that phase correction can readily be performed using the aligned phase history data during batch processing. In its simplest form, the invention (44) is comprised of two main parts. First (60), alignment of the phase error profile is achieved by proper phase adjustment in the spatial (or image) domain using a quadratic phase function. Second (62), the common phase error can be corrected using autofocus algorithms. Two alternative embodiments of the invention are described. The first embodiment (44a) adds padded zeros to the range compressed data in order to avoid the wrap around effect introduced by the FFT (Fast Fourier Transform). This embodiment requires a third step (64): the target dependent signal support needs to be shifted back to the initial position after phase correction.

Abstract: A mixed technology microcircuit including a first circuit fabricated on a first layer with a first technology and a second circuit fabricated on a second layer with a second technology. In the illustrative embodiment, the first circuit is fabricated with silicon germanium (SiGe) technology and the second circuit is fabricated with complementary metal-oxide semiconductor (CMOS) technology. In an illustrative application, the first circuit includes a high-speed data receiver and a high-speed data transmitter. In the illustrative implementation, the data receiver includes a line receiver, a data and clock recovery circuit, and a demultiplexer and the data transmitter includes a multiplexer, a data and clock encoding circuit, and a line driver.

Abstract: A cancellation technique embodied in a system and a radar signal processing method that is employed to detect near-range targets. The present invention uses a frequency-modulation continuous-wave (FMCW) or stepped frequency waveform and is capable of detecting near-range targets that would normally be obscured by transmitter leakage and internal reflections. This cancellation technique works by transmitting one or more reference ramp signals and then subtracting the coherent average of the transmitted reference ramp signals from a group of succeeding transmitted and received ramp return -signals. The resulting group of FM ramp return signals is noncoherently integrated to achieve more stable target detection statistics. More particularly, the present technique implements the following processing steps. Generating a predetermined number of reference ramp signals. Coherently averaging target return signals corresponding to transmitted reference ramp signals to produce a reference average signal.

Abstract: An electrical joint that couples electric signals and current between objects that move relative to one another. A conductive slurry is disposed upon a first object and a conductor extends from a second object to engage the conductive slurry. The slurry comprises conductive particle suspended in a fluid carrying agent, such as oil. A non-conductive gel may be disposed upon the exposed surface of the conductive slurry to retain and protect it. The conductive slurry and non-conductive gel may be disposed within a channel on the object's surface so as to define their position and retain them in the desired area. The position of the conductive slurry is oriented and aligned to maintain continuous contact with the conductor as movement occurs. Linear, planar, circular and other movements are contemplated. The electrical joint can be readily adapted to printed circuit and printed wire technology.

Abstract: A system and method (44) for focusing an image oriented in an arbitrary direction when the collected synthetic aperture radar (SAR) data is processed using range migration algorithm (RMA). In accordance with the teachings of the present invention, first (60) the data is skewed so that the direction of smearing in the image is aligned with one of the spatial frequency axes of the image. In the illustrative embodiment, the smearing is aligned in the vertical direction. This is done through a phase adjustment that was derived from the requirements for proper shift in the spatial frequency domain. Next (62), the signal support areas from all targets are aligned by proper phase adjustment in the spatial (or image) domain. Finally (64), the common phase error can be corrected using autofocus algorithms.