Abstract: A unity power factor power supply includes a boost converter. The boost converter draws current in phase with the input voltage by operating as a current regulator having a current reference control signal which tracks the line voltage waveform. A sample and hold technique is utilized to accommodate single cycle step input compensation and to reduce harmonic distortion over a wide input frequency range.

Abstract: A method and apparatus for monitoring the performance of a liquid-crystal display driver is described. The monitoring apparatus includes an analog feedback stage comprising an array of analog switches including a single switch for each output of the display driver wherein the output of each switch is connected to a single feedback line. A control circuit selectably actuates any of the switches such that the corresponding display driver output line is connected to the feedback line. The signal at any selected display driver output line may be monitored to ensure proper functioning thereof. The performance of the display drivers and supporting circuitry may be thereby monitored.

Abstract: Provided are a method of and apparatus for applying a chemical to an agricultural field. A current position of chemical application equipment used to apply the chemical to the field is determined. A desired application rate for a first position a distance d ahead of the current position of the chemical application equipment is determined or retrieved from a data base containing a plurality of chemical application rates for the injector channels. The chemical application equipment is controlled, while the chemical application equipment is approximately at the current position, to change the chemical application rate from a current application rate to the desired application rate if the desired application rate is within a predetermined range, and to maintain the current application rate if the desired application rate is outside of the predetermined range, and for accurately recording chemical application rate and position data.

Abstract: A method of reducing jamming in a global positioning system (GPS) satellite receiving system includes the steps of: a) selecting an initial weight value corresponding to each antenna element; b) selecting a weight adjustment scheme for adjusting the weights; c) measuring a power output from the antenna array; d) obtaining navigational data representing the orientation of the array; e) calculating for a gain of the antenna array corresponding each of the GPS satellites, using the navigational data to provide an indication of the orientation of the array relative to each GPS satellite; f) estimating a power level of a received signal corresponding to each GPS satellite; g) solving for the signal to noise ratio for each GPS satellite, using the estimated power level corresponding to each GPS satellite; h) iteratively and continuously adjusting the weights to obtain a greatest value of the signal to noise ratio; and i) continuously repeating steps (c) through (h).

Abstract: A method for establishing simultaneous communications between nodes having neighboring nodes in a multi-hop network of transceiver nodes arranged in neighborhoods includes determining the quality of communication links between the nodes of a neighborhood and adjacent neighborhoods. A table of quality data is stored representing the quality of communication links between nodes of the neighborhood for each node. A set of performance criterion of desired service in the neighborhood is stored. A set of possible link assignments between ones of the nodes in the neighborhood is generated from the table of quality data based upon a maximized performance criterion of desired service in the neighborhood. Link assignments are then allocated between nodes of the neighborhood based upon the desired performance criterion.

Abstract: A transformer over-voltage protection circuit shuts down a resonant inverter when high voltages occur at the output of a transformer. The high voltages can be caused by a broken or removed display tube. The system is designed to be used in display system, such as, an active matrix liquid crystal display (AMLCD). The system senses the voltage at the output of the transformer by utilizing a tickler or a tertiary winding. The signal from the tertiary winding is rectified and compared to a threshold. If the signal from the tertiary winding is greater than the threshold, the inverter is shut down for a period of time.

Abstract: A swathing guidance display for accurately guiding and navigating an agricultural product application vehicle is described. The invention aids in precision guidance of the application of agricultural products such as fertilizers and herbicides to reduce application overlap. The invention further provides assistance in planting operations without requiring the use of traditional markers, provides parallel swath guidance of an agricultural product application vehicle, and provides an apparatus which providing a vector for navigating an agricultural product application vehicle to a desired application location. The swathing guidance device includes a circular display having a plurality of illuminating radial vectors to indicate the direction of the desired course and course correction. Both guidance and navigational functions are provided.

Abstract: A platform attitude determination can be made with a single receiver in a global positioning system (GPS). The receiver receives at least three sets of GPS signals from three antennas. Two of the GPS signals are delayed so that the receiver receives each GPS signal in separate time domain slots. In this way, the synchronization of separate GPS receivers does not have to be accomplished.

Abstract: A simplified system for integrating a distance measurement derived from an additional navigation system into an existing aircraft design by creation of a Distance integrator function that makes use of existing Distance Measuring Equipment to couple the additional navigation system into the aircraft's display and navigation systems.

Abstract: Illustrative embodiments of a method and apparatus are provided for determining azimuth for a system using signals from a constellation of satellites of the global navigation satellite system. The method includes the steps of identifying a direction of a selected satellite of the constellation of satellites and determining a azimuth by correlating the identified direction of the selected satellite with the location of the system.

Abstract: A global positioning system (GPS) receiver and high accuracy low power time source (HAL) are disclosed. The HAL provides a time source having an accuracy which is high enough for the receiver to achieve fast direct Y-code acquisition. The HAL includes an oscillator adapted to provide an uncompensated frequency signal at a desired frequency. Frequency conversion circuitry receives the uncompensated frequency signal and a control signal as inputs, and provides as an output a compensated frequency signal having an average compensated frequency which is closer to the desired frequency than is the average uncompensated frequency. A temperature sensor provides an output indicative of a temperature of the oscillator. Frequency error determining circuitry determines an error value, as a function of the temperature sensor output, which is indicative of a quantity of frequency error over time in the uncompensated frequency signal.

Abstract: A method and an apparatus for driving a passive liquid crystal display to obtain a high contrast ratio for both still image and video modes includes driving some or all of the row lines simultaneously. The row voltage wave forms are defined as a set of orthogonal functions and the column voltage wave forms are defined as a linear combination of the row voltages. The mean square voltage across each pixel and row is specified, and the corresponding column coefficient is calculated from which all coefficients in a column can be determined.

Abstract: A visual display format for a terrain situational awareness system comprising a horizontal terrain elevation view and a profile terrain elevation view of potential terrain hazards integrated onto a single display.

Abstract: A system for adaptively determining a bitwise weighting factor for coded binary data comprising a correction unit that provides an overall weighting factor representative of the sum of the products of the individual symbol probability factor times the bit value.

Abstract: A commercial vehicle fleet management system which integrates a vehicle on-board computer, a precise positioning system, and communication system to provide automated calculating and reporting of jurisdictional fuel taxes, road use taxes, vehicle registration fees, and the like. Also disclosed is an online mobile communication system and a system for monitoring carrier vehicle efficiency and vehicle and driver performance.

Abstract: A connected fiber optic electrical or avionics system is disclosed. The system includes a line replaceable unit (LRU), such as an avionics primary flight display LRU, adapted for insertion into a chassis such as an airframe. An LRU connector coupled to the LRU and adapted for mating with a chassis connector plug includes an active optoelectronic device mounted therein for operatively coupling to an optical termination in the chassis connector plug. Inclusion of the active optoelectronic device in the LRU connector eliminates the need for the active optoelectronic device to be mounted on a printed circuit board, as well as the need for a fiber pigtail connecting the connector and the printed circuit board.

Abstract: An automatic link establishment (ALE) method of establishing a link between two or more HF radios or stations, and an apparatus using the same, are disclosed. The invention provides a transmission protocol that allows HF radios to rapidly exchange call data to enable the first radio and second radio to have knowledge of the frequency propagating characteristics used for communication. The method includes transmitting 24 bit words from the first station to the second station and vice-a-versa in the CALL. The words include a three bit preamble, at least about 3 bits of data to be transmitted from the second station to the first station, and a compressed representation of three characters of the address of at least one of the stations. The number of words transmitted during the CALL, RESPONSE and ACKNOWLEDGE are greatly reduced from the protocol defined in MIL-STD-188-141A Notice 2.

Abstract: An aircraft entertainment system employing a hybrid video distribution system that permits distribution of direct broadcast satellite television programming to passengers of the aircraft. The aircraft entertainment system has a video control center 11, a plurality of groups of seat display units 40, and a plurality of audio and video processors 20 that control routing of programming to each seat display unit. A plurality of seat junction boxes 30 may be interposed between the audio and video processors 20 and the groups of seat display units 40. An antenna 12 is receives programming from a satellite, and a splitter 13 generates a plurality of channels of programming received by the antenna 12. A decoder 14 decodes the channels to provide video and audio signals, and an RF modulator 16 modulates the decoded audio and video signals for distribution.

Abstract: A control system for aiding the operator of a vehicle or platform, such as an aircraft. The system includes a receiver adapted to receive a voice command from a controller located remotely from the vehicle or platform. A speech recognition device is coupled to the receiver and adapted to compare the voice command to speech recognition templates of known voice commands. A match between the voice command and a speech recognition template is indicative of informational content of the voice command. A display device coupled to the speech recognition device displays to the operator of the vehicle or platform a visual representation of the informational content of the voice command.

Abstract: Disclosed are a backlight and a method of driving the same to provide a uniform low intensity source of light for a liquid crystal display. The fluorescent lamp includes a fluorescent lamp and a drive circuit coupled to the anode and to the cathode of the fluorescent lamp for supplying the fluorescent lamp with a drive current. First and second longitudinally extending substantially transparent conductor members are disposed externally along the length of the lamp. A radio frequency (RF) signal generator connected to each of the first and second longitudinally extending conductor members drives the first and second conductor members with an RF signal to generate a dynamic RF electric field within the glass tube.