Patents Represented by Attorney, Agent or Law Firm Wanda K. Denson-Low
  • Patent number: 5717405
    Abstract: A four-port transmission line device that processes two incoming RF signals of arbitrary phase and amplitude to output two corresponding RF signals of equal phase and amplitude. Two sets each of two quarter-wave transmission line segments are connected in series between corresponding input and output ports. A short circuit interconnect shorts together the junctions of the two series connected line segments. A resistive element is connected across the two input ports, and another resistive element is connected across the two output ports. The short circuit interconnection forces the combination of the two input signals into one resultant signal at the short circuited junction. Out-of-phase components of the resultant signal are absorbed in the resistor across the input ports. The remaining in-phase components are divided into two outputs signals of equal phase and amplitude.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: February 10, 1998
    Assignee: Hughes Electronics
    Inventor: Clifton Quan
  • Patent number: 5715094
    Abstract: A helmet/head mounted display including a display image source and a reflective visor for each eye. The image source includes a fiber optic cover plate with a planar input surface and a curved output surface which has curvature providing the correct curvature. The image source further includes a self-emitting device such as a field electrode display or electroluminescent device, or a polymer dispersed liquid crystal (PDLC) sandwiched between a thin, sharply tapered fiber optic plate and the fiber optic cover plate. For the PDLC image source, back light illumination is introduced through the tapered fiber optic plate, passes through or is scattered by the PDLC and then through the fiber optic face plate to the visor, for reflection to the observer's eye. The fiber optic face plate is constructed with a very low numerical aperture. The fibers of the cover plate are oriented toward the eye as seen in the reflection from the visor to reduce undesirable reflected light.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: February 3, 1998
    Assignee: Hughes Electronics
    Inventors: David A. Ansley, Chungte W. Chen, Ronald G. Hegg
  • Patent number: 5711196
    Abstract: A tooling apparatus and method for machining a blank having a first surface portion with a first spin center and a second surface portion with a second spin center offset from the first spin center. The improved tooling apparatus includes a turning fixture connectable to a rotatable spindle in one of a first position and a second position. The first spin center of the blank aligns with the axis of rotation of the spindle when the turning fixture is in its first position and the second spin center of the blank aligns with the axis of rotation when the turning fixture is in its second position. In the preferred embodiment, the rotatable spindle includes a dowel cooperative with first and second bores formed in the turning fixture to position the turning fixture relative to the spindle. The first and second bores are separated a distance equal to the distance between the first spin center and the second spin center of the blank.
    Type: Grant
    Filed: April 25, 1996
    Date of Patent: January 27, 1998
    Assignee: Hughes Electronics
    Inventors: John Reid, Conrad Stenton
  • Patent number: 5712642
    Abstract: An array antenna (10) that can form and sweep a predicted radiation beam pattern in different directions by using a subharmonic frequency signal from each voltage controlled oscillator (VCO) (20) to control the array phasing. Each VCO (20) generates a radio frequency carrier signal that drives an antenna element (16). A subharmonic signal is generated from a portion of the signal from the VCO (20). The subharmonic signal is mixed with a constant frequency signal to produce an intermediate frequency (IF) signal. The frequency of the IF signal is compared to the frequency of a variable frequency signal in a phase locked loop (PLL) (40). Since the phase of a signal is dependent on its frequency, the variable frequency signal is generated to have a frequency corresponding to a certain phase. The PLL (40) generates an error signal as a function of the difference in frequencies between these two signals. In response to the error signal, the VCO (20) changes the frequency of the carrier output signal.
    Type: Grant
    Filed: February 5, 1996
    Date of Patent: January 27, 1998
    Assignee: Hughes Missile Systems Company
    Inventor: Garry N. Hulderman
  • Patent number: 5710625
    Abstract: A device for holding and positioning a sample (22) during spectral analysis, having an optical cell (41) comprised of a base member (42), a glass cell (44), and being filled with oil (46) having substantially the same index of refraction as the glass cell (44). The device further includes a rotary stage device (48) attached to the optical cell (41) and a sample holder (50) attached to the rotary stage device (48) such that a sample (22) may be rotated over a range of angles relative to a projected beam (32) to provide a spectral analysis of the sample (22) over the range of angles.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: January 20, 1998
    Assignee: Hughes Electronics
    Inventors: Margarete Neumann, Robert Pursel
  • Patent number: 5710661
    Abstract: An optical apparatus monitors the entire panorama in low resolution and simultaneously monitors a selected portion of the panorama in high resolution. For the panoramic portion of the apparatus, a mirror having a convex surface of revolution with a hole therein is used. The higher resolution part of the apparatus uses a pointing mirror positioned above this hole. The panoramic and higher resolution views are imaged through lenses or optical components onto a detector. The panoramic view is imaged onto the detector as an annulus of light in which either higher or lower elevational angles of the panorama are imaged further away from the detector's center depending upon how the convex mirror is configured. In this way, the resolution of that portion of panorama that is imaged further away from the detector's center is enhanced. The higher resolution view is imaged to the center of the annulus.
    Type: Grant
    Filed: June 27, 1996
    Date of Patent: January 20, 1998
    Assignee: Hughes Electronics
    Inventor: Lacy G. Cook
  • Patent number: 5707128
    Abstract: An alignment system and method for maintaining the alignment of a target projector with another image projector in a simulator system. The target projector system includes a slewable fold mirror to move the target image in azimuth and elevation. A two position beam splitter is arranged so that in a projector operating mode, the beam splitter is positioned out of the target projector image light path, and in a projector maintenance mode, the beam splitter is positioned in the image light path. A photo-sensitive array is positioned relative to the beam splitter such that light from the display screen is redirected from the light path onto the array. During the maintenance mode, reference light points are generated on the display screen, and the target projector is precisely aligned by use of processing the images captured by the array to calculate an error signal representing the distance between the light point image and the center of the array.
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: January 13, 1998
    Assignee: Hughes Electronics
    Inventor: Jon Dugdale
  • Patent number: 5708442
    Abstract: A passive imaging system that uses an antenna having two antenna elements. The system cross-correlates received signals with a reference function to achieve high resolution. The antenna elements are rectangular with their long dimensions oriented normal to the longitudinal axis of a carrying vehicle and the elements are separated by a distance consistent with image resolution requirements. Additionally, the antenna elements are frequency scanned in the cross-track dimension. The channel for the forward antenna element has a time delay relative to that of the rear antenna element. This time delay achieves pointing of the antenna at a particular forward angle relative to the normal to the velocity vector. Outputs of IF filters of the antenna elements are synchronously detected to provide in-phase and quadrature (I/Q) components of their phase modulated product.
    Type: Grant
    Filed: April 24, 1996
    Date of Patent: January 13, 1998
    Assignee: Hughes Electronics
    Inventors: David A. Whelan, Henry L. McCord
  • Patent number: 5708336
    Abstract: The present invention is a temperature control system for a motor coupled to a power source. The motor has at least one winding which serves as a heater and temperature sensor as well as producing torque during normal operation. The mathematical relationship between temperature and resistance in the motor winding is used to determine the winding temperature. The actual winding temperature is then compared to a desired operating temperature, and the current to the motor winding is controlled so as to keep the motor temperature within a desired range.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: January 13, 1998
    Assignee: Hughes Electronics
    Inventors: Bruce N. Eyerly, Peter L. Conley
  • Patent number: 5708380
    Abstract: A flip-flop circuit that includes a first NAND gate (11) responsive to a D input to the flip-flop circuit and a first mode control signal for providing a first NAND gate output; a second NAND gate (12) responsive to a serial scan input to the flip-flop circuit and a second mode control signal for providing a second NAND gate output; an inverter (21) responsive to the first NAND gate output for providing an inverter output; a first transmission gate responsive to the first NAND gate output and the second NAND gate output for providing a first transmission gate output, the first transmission gate output being a replica of the inverter output when the first mode control signal is of a first logical state and the second mode control signal is of a second logical state, and the first transmission gate output being of high impedance when the first mode control signal is of the second logical state and the second mode control signal is of the first logical state; a second transmission gate (32) responsive to the fir
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: January 13, 1998
    Assignee: Hughes Electronics
    Inventor: William D. Farwell
  • Patent number: 5708835
    Abstract: A dual-directional parallel processor. The inventive processor (10) includes an array (20) of processing elements (30). Each processing element has a first circuit (31) for inputting and outputting data, a second circuit (32) for inputting and outputting data; and a third circuit (33, 34) for setting the first circuit (31) in an input mode and for setting the second circuit (32) in an output mode in response to a first mode control signal. The third circuit (33, 34) also sets the first circuit (31) in an output mode and the second circuit (32) in an input mode in response to a second mode control signal. In the illustrative embodiment, data is communicated between the first and the second circuits (31, 32) and the processor further includes a fifth circuit (12) for inputting data to the array and a sixth circuit (14) for outputting data from the array.
    Type: Grant
    Filed: March 27, 1995
    Date of Patent: January 13, 1998
    Assignee: Hughes Electronics
    Inventor: Robert W. Burnett
  • Patent number: 5708573
    Abstract: A DC to DC converter including a resonant switching circuit (13, 51 , 115, 151, 125, 153); an impedance matching circuit (53) responsive to the resonant switching circuit; a rectifier circuit (55) responsive to the impedance matching circuit; an output filter circuit (57) responsive to rectifier circuit for providing a filtered DC to DC converter voltage output; and a varactor diode circuit (27, 29, 31, 61) responsive to the filtered DC to DC converter voltage output for controlling the impedance matching circuit such that the filtered DC to DC converter output voltage is substantially constant.
    Type: Grant
    Filed: February 1, 1996
    Date of Patent: January 13, 1998
    Assignee: Hughes Electronics
    Inventors: David M. Lusher, Wilbur E. Hong, William B. Hwang
  • Patent number: 5705962
    Abstract: Microwave apparatus, such as microwave power dividers or combiners, having an adjustable terminating resistor. The present invention allows adjusting or trimming of the resistor and pretesting of substrates on which the apparatus is formed prior to installation of expensive integrated circuit components. The microwave power divider or combiner has a central contact disposed at a midpoint of the terminating resistor. This central contact is thus disposed at the midpoint of the terminating resistor and is coupled to a test point. Outer edges of the central contact are constructed to be parallel to inner edges of impedance paths or traces over which the terminating resistor lies so that each section of the terminating resistor has substantially the same resistance value.
    Type: Grant
    Filed: December 31, 1996
    Date of Patent: January 6, 1998
    Assignee: Hughes Electronics
    Inventors: Robert G. Fleeger, Alan L. Kovacs
  • Patent number: 5706011
    Abstract: A method that enables an aircraft to determine an optimal terrain following, terrain avoidance, or threat avoidance trajectory over terrain, thereby reducing its exposure and increasing its survivability. A grid of discrete terrain points corresponding to the terrain above which the aircraft is to fly is formed. Each point has a cost that is function of predetermined criteria. A cost is assigned to each of the points that is representative of the cost to get to the point based upon the predetermined criteria. A terminal point is selected that is a point that must be flown through at the end of the trajectory over the terrain, or in order to clear an obstacle in the flight path of the aircraft. A series of paths is computed through the terrain points to a selected terminal point, taking into account the aircraft's maneuvering capability and current attitude.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 6, 1998
    Assignee: Hughes Electronics
    Inventors: Ronald E. Huss, Mark A. Pumar
  • Patent number: 5706457
    Abstract: A system 10 and methods for acquiring and archiving images derived from multiple sources with minimal operator interaction and understanding of the archiving computer 11. The system 10 and methods provide for reception of digitized images via modem 24 from a remote source, and the input of images from local sources including a digital photographic image source 25 such as a digital camera or 35 millimeter digitizing camera data back, an optical scanner 23, and digitized images previously stored on magneto-optical disk or digital audio tape. The system 10 also archives and distributes image and document data to multiple destinations, including a magneto-optical drive 22, digital or hard disk drive 15, and to laser or photographic quality continuous tone printers 26, 27.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 6, 1998
    Assignee: Hughes Electronics
    Inventors: Douglas A. Dwyer, James E. Handy, Paul E. Curry, Rick E. Pflugshaupt, Kevin B. Grant
  • Patent number: 5705283
    Abstract: A rocket engine component is formed as a tungsten-copper composite substrate, and a functionally-gradient material coating overlying and contacting the substrate. The functionally-gradient material coating has a composition that varies nonlinearly through a thickness of the coating so as to minimize thermal stresses through the coating, and such that the functionally-gradient material coating is tungsten adjacent to the substrate and is rhenium remote from the substrate. In a preferred form, the functionally-gradient material coating includes a tungsten sublayer overlying and contacting the substrate, a tungsten-rhenium sublayer overlying and contacting the tungsten sublayer; and a rhenium sublayer overlying and contacting the tungsten-rhenium sublayer. The functionally-gradient material coating is preferably applied by a low-temperature deposition technique such as plasma enhanced chemical vapor deposition.
    Type: Grant
    Filed: June 13, 1996
    Date of Patent: January 6, 1998
    Assignee: Hughes Electronics
    Inventor: Kamleshwar Upadhya
  • Patent number: 5706107
    Abstract: A holographic viewing apparatus for allowing an operator of a bus to view a portion of a blind spot region located in front of the bus and below the windshield of the bus. The holographic viewing apparatus includes a volume transmission holographic grating attached to a lower edge of the windshield of the bus for transmissively diffracting light from a portion of the blind spot region such that an operator of the bus sees an image of the portion of the blind spot region superimposed on a scene that is directly and non-diffractingly observed through the holographic transmission grating.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: January 6, 1998
    Assignee: Hughes Electronics
    Inventor: Ronald T. Smith
  • Patent number: 5703599
    Abstract: An offset RF interconnect structure for interconnecting an active array radiating aperture to a transmit/receive (T/R) module sub-array, wherein the corresponding input/output (I/O) ports lie on different lattices. The interconnect structure employs dielectric-filled slabline transmission line, which includes a center conductor wire conductor bent to form the offset interconnection between two ports misaligned in two dimensions. The structure includes a dielectric housing that is formed by injection molding about the center slabline wire conductor. The offset interconnect structure can be integrated with an in-line coaxial interconnect structure.
    Type: Grant
    Filed: February 26, 1996
    Date of Patent: December 30, 1997
    Assignee: Hughes Electronics
    Inventors: Clifton Quan, Peter Holbrook, Bill Batterton, Pat Fitzgerald, Dan Roper, Min Takaki
  • Patent number: 5703538
    Abstract: A phase lock acquisition control circuit for the local oscillator (LO) of a radar exciter. The control circuit includes a programmable logic array, a microsequencer and a counter employed as a divide-by-eight circuit which supplies a clock reference for the control circuit. The counter in turn is clocked by a crystal based oscillator also used as the reference for the exciter phase lock loop. The marker filter and zero beat detector provide frequency location information to the control circuit. The control circuit controls a ramp generator circuit which in turn can drive the phase lock loop VCO during acquisition.
    Type: Grant
    Filed: September 18, 1996
    Date of Patent: December 30, 1997
    Assignee: Hughes Electronics
    Inventors: Chester K. C. Lo, Paul I. Tanaka
  • Patent number: 5703590
    Abstract: A method wherein the scan rate of an active emitter is simultaneously estimated by a tracking receiver and a radar system and are then compared to correlate tracks generated by the tracking receiver and the radar system. The output produced by the present method provides for data that is more accurately indicative of the locations and identifications of emitters tracked by the tracking receiver and the radar system. More specifically, the method comprises the following steps. An active emitter having a scanning antenna is simultaneously tracked using a tracking receiver and a radar system. The location of the emitter is estimated using the tracking receiver by processing measurements of the electromagnetic signals generated by the emitter. The scan rate of the emitter is estimated using the tracking receiver by detecting strobing of the main lobe of the signals generated the emitter. The scan rate of the emitter is estimated using the radar system.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: December 30, 1997
    Assignee: Hughes Electronics
    Inventors: Steve Roth, Thomas A. Kennedy