Abstract: An impedance measurement system rapidly determines impedance of a sinusoidal signal at a known frequency. The sinusoidal signal can represent a forward voltage, a reflected voltage, a voltage, or a current on a transmission line. The impedance calculation is made by receiving two samples of a signal representing forward voltage and reflected voltage or two samples each of current and voltage. The samples are used to determine an amplitude value and a phase value for the signal. The amplitude and phase value are utilized to calculate the impedance.

Abstract: A system of utilizing a single radio receiver with continuously broadcast GPS signals in order to determine precise relative positioning between two arbitrary positions or to determine current position. The invention includes utilizing changes in the carrier signal as detected by the GPS receiver occurring as a result of the movement from a first position to a second position.

Abstract: An FMS with the capability of automatically adjusting the view of the flight path as the flight progresses while maintaining a set viewing direction. The vertical dimension of the flight path display chosen to fill the display and provide increased readability.

Abstract: A global positioning system (GPS) and auxiliary receiver receive limited range position signals broadcasted from telemetry transmitters when in an urban canyon environment. The limited range receivers preferably are implemented as part of the lighting infrastructure of the environment. The limited range receivers derive power from light from the lighting infrastructure. The receivers can also include a transmitter for retransmitting the receive position data and an ID code to a central processing center.

Abstract: Disclosed are global navigation satellite system (GNSS) receivers, including digital spatial nulling arrays, and a method of providing antenna pattern outputs using the same. The digital spatial nulling array receives multiple antenna element inputs. A fast Fourier transform (FFT) is applied to the multiple antenna element inputs to obtain frequency domain representations of the multiple antenna element inputs. The antenna pattern outputs are provided by the spatial nulling array as a function of the frequency domain representations of the multiple antenna element inputs.

Abstract: A lightning protection element is incorporated into the portion of an aircraft signal distribution system which connects an antenna to flight critical equipment. The lightning protection element rejects surge currents associated with direct lightning strikes on the antenna, or its surrounding radome, while passing communication signals without significant interference with those signals. In a preferred embodiment, the lightning protection element comprises an optical fiber isolator element. A segment of optical fiber in the isolator prevents surge currents associated with the lightning strikes from reaching the equipment while passing communications signals transmitted on the signal distribution system.

Abstract: The disclosure describes a moving receiver station capable of receiving broadcast entertainment signals from a first geostationary satellite associated with a first program provider, or from a second geostationary satellite associated with a second program provider. The receiver station is part of an aircraft and includes a tracking antenna and switching and control system that locks the tracking antenna on either the first or second satellite. The switching and control system receives position information, program attribute information and satellite coverage area information to determine when the aircraft is leaving one coverage area and entering another. The switching and control system switches the antenna to the second satellite when the aircraft enters the second coverage area, and limits the availability of received programming based on whether the aircraft is leaving the first coverage area or entering the second coverage area.

Abstract: A method and apparatus for correlating outputs of a plurality of environmental sensor signals to determine a situation. The method includes the steps of dividing a coherent light beam across a diameter of the light beam into a plurality of information transmission zones and modulating a portion of the light beam within at least some of the information transmission zones with a corresponding number of signals of the plurality of environmental sensor signals. The method further includes the steps of deflecting the modulated light beams of the at least some information transmission zones within a holographic memory to provide at least some correlated outputs among the plurality of environmental sensor signals and determining the situation based upon the at least some correlated outputs of the holographic memory.

Abstract: An infinitely adjustable position sensor is provided. The position sensor can be used as a head position switch which generates an output indicative of a position of a harvesting head of a harvesting vehicle, or in similar applications with other types of equipment. The sensor includes a body attachment mechanism for coupling the sensor to the body of the vehicle or other equipment, and a head attachment mechanism for coupling the sensor to the feeder house which supports the harvesting head. For adjustment of the sensor, particularly prior to operation, visual feedback is provided by an LED ring in order to inform the operator of the state or position of the sensor.

Abstract: A programmable divider or prescaler divides an input signal by a divisor of two raised to the m.sup.th -power plus one, (2.sup.m +1), where m is an integer, and n is a value between zero and two raised to the m.sup.th -power minus one, (2.sup.m -1). When m is equal to 3, the duty cycle is between 44% and 56%. The divider can be utilized in communication applications for providing radio frequency source signals. The duty cycle is maintained around 50% for use with balanced mixers.

Abstract: A display apparatus adapted for viewing by a person wearing linearly polarized lenses, such as sunglasses, is disclosed. The display apparatus includes a display device, such as an LCD or a filtered TFEL display, which displays information by providing as an output linearly polarized light travelling toward the person viewing the display apparatus. A quarter-wave plate is positioned between the display device and the linearly polarized lenses of the sunglasses. The quarter-wave plate receives the linearly polarized light from the display device as an input and provides as an output circularly polarized light which passes through the linearly polarized lenses of the sunglasses substantially without attenuation.

Abstract: A novel dielectric heater including a RF source having a first impedance, a parallel plate mold having a second impedance, and an impedance network, matching the first impedance to the second impedance, connected to the RF source and the parallel plate mold. The impedance network may be connected in series with the RF source and the parallel plate mold. The RF source may include a RF terminal and a common terminal, the impedance network may include a first terminal, connected to the RF terminal, and a second terminal, and the parallel plate mold may include a first plate, connected to the second terminal of the impedance network, and a second plate, connected to the common terminal of the RF source. In an alternative embodiment the novel dielectric heater includes parallel plates divided into a number of series-connected cells. The series cells lower the capacitive component, and may be configured such that an impedance of the parallel plate mold approximates an impedance of the RF source.

Abstract: A global navigation satellite system (GNSS) receiver for use in an aircraft is disclosed. The GNSS receiver includes receiver circuitry for receiving satellite signals containing satellite data from a multiple GNSS satellites. The receiver circuitry generates a first navigation solution for the aircraft as function of the satellite data. A first GNSS receiver output couples to an inertial reference system (IRS) and provides the satellite data to the IRS. The IRS generates a second navigation solution for the aircraft as a function of the satellite data and as a function of IRS position data. A first GNSS receiver input couples to the IRS and receives the second navigation solution from the IRS. The GNSS receiver provides at a second output aircraft position information as a function of the second navigation solution.

Abstract: A programmable data port interface adapter for a mobile data terminal is disclosed which provides selectable configuration of an external device data port connector for accommodating multiple types of data port devices. An RS-232 type data port may be configured to a J1708 type data port such that the mobile data terminal may communicate with RS-232 type devices in addition to J1708 type devices. Data port configuration and control is implemented by software thereby eliminating the need to upgrade of modify data port hardware to accommodate multiple data port type devices. Multiple data port connectors may be utilized in a multiple programmable combinations and configurations. Configuration information may be received by the mobile data terminal or through remote communications such as an RF or cellular network.

Abstract: A selector assembly for use in avionic multifunctional displays to perform quadrature and push button functions is described herein. The selector assembly utilizes two sensors and a cylindrical band with an encoder pattern having three distinct zones to sense either direction of rotation (quadrature) of a knob or its push motion. The pattern can include regions that are absorptive and reflective to infrared (IR) energy. The selector assembly uses the two sensors to sense a pattern rotation or a push motion of the pattern, thereby reducing the number of mechanical and sensing components and simplifying the wiring associated with the assembly. The encoder pattern is molded either directly on the inside of the knob or on a label that is adhered to the interior surface of the knob. The physical components and the sensors of the encoder mechanism are also placed within the knob of the selector assembly, thereby optimizing the useable glass surface area available for avionic displays.

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: 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: 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 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.