Abstract: A method and system for radio communications between mobile units and base stations geographically distributed through a substantial geographic area described. The system automatically finds and engages broadcast frequency for each geographic region. The engagement is confirmed at both the mobile unit and network so that both can begin data transmission and reception between each other as well as keep track of the status of one another. The system also verifies the correct base station has been engaged as well as automatically terminates communications once the mobile unit passes out of coverage for that base station.

Abstract: A dual filament fluorescent lamp where the individual filaments are disposed along diameter lines of a fluorescent tube and are disposed on differing planes at differing heights within the tube with a predetermined separation between the tube filaments and the filaments being disposed in a perpendicular fashion when viewed from above. The primary filament is disposed above the secondary filament and it has a larger diameter that the secondary filament.

Abstract: A system for customizing the ramp voltage pulses used to drive an active matrix liquid crystal display. The customized ramp voltage compensates for brightness problems associated with any number of parameters. The V (ramp) also can allow for customized dimming of portions of the display. The standard V (ramp) is replaced with a variable wave form correlated to the timing of the driving of the LCD. The wave form can compensate for changes in brightness caused by off axis viewing angle or can compensate for brightness changes caused by temperature. Also, the system is directed to spatially modulating brightness of pixels for an active matrix LCD to correct color or brightness problems. A driving voltage wave form, which is varied as a function of location on LCD and grey scale is generated to cause selected sets of pixels to be adjusted from an instructed grey scale.

Abstract: An improved autopilot system of the type which uses pitch commands to control airspeed with an improvement of including a temporary pitch hold command being issued if thrust changes would oppose the autopilot pitch command. The temporary pitch hold command would end when the airspeed reaches a calculated airspeed capture point.

Abstract: An arrangement for generating a digital, downconverted complex baseband signal from a bandpass signal comprises a signal source for providing first and second clock signals at first and second clocking rates, respectively. The first clocking rate is at four times the expected center frequency of the bandpass signal, and the second clocking rate is at an exact subharmonic frequency of the bandpass frequency. The bandpass signal is sampled by a composite sampling event of two sampling pulses which occur once during each period of the second clocking signals and which are time-spaced from each other by the inverse of the first clocking rate. The complex baseband samples are ready as an A/D converter output, with no requirement for DSP processing to complete the downconversion to zero-IF.

Abstract: An apparatus and method for improving the performance of a satellite communications modem is disclosed. The invention is particularly applicable to mobile satellite receivers, and includes a variable-gain automatic frequency controlled (AFC) loop, the gain of which is controlled adaptively, based on the AFC lock status and the lock status of the modem's inner loop, in addition to other parameters determined by the invention.

Abstract: A magnetically variable inductor for high power, high frequency applications which includes a solenoid with a magnetic core therein, disposed coaxially around a conductor for carrying the high power, high frequency signal and a variable current source coupled with the solenoid so that a manipulation of the current through the solenoid results in a variable inductance for said conductor. Also disclosed are additional features of ferrite rings disposed around each end of the magnetic core, a shield disposed between the core and the solenoid, and a sheath disposed around the solenoid.

Abstract: A regulated and constrained current source is used to drive the cathodes of a hot cathode gas discharge lamp to provide heating during lamp operation. In one embodiment, the regulated current source is time shared between the lamp cathodes and the lamp arc.

Abstract: A transceiver which operates in separate transmit and receive bands has a first conversion stage for generating a first IF signal translation of a receive signal, which first conversion stage also functions as a first and final, hence, single conversion stage for generating a transmit signal at its transmission frequency. A modulated transmit signal component used in the single conversion to the transmission frequency of the transmission signal has harmonics which lie outside the transmission band and is of a frequency which permits a substantial overlap of transmit and receive injection frequencies generated by a first numerically controlled signal generator which are applied to a first mixer of the first conversion stage during respective transmit and receive mode operations.

Abstract: A railroad in-cab signaling system which includes transceivers disposed at signals where various transceivers are operating on different frequencies and addresses so as to provide for easy identification and highly secure communication to the signal transceiver and a tunable transceiver disposed on the locomotive, the locomotive transceiver being coupled to an interrogator which interrogates transponders disposed in the tracks, the transponders providing a message containing the predetermined frequency and address of the signal transceiver thereby allowing the locomotive transceiver to tune to the appropriate frequency and established a connection for the signal which it is approaching. The locomotive transceiver and the signal transceiver are then capable of exchanging information along the entire distance from the transponder to the signal.

Abstract: An active ring laser gyroscope having two optical amplifier diodes therein which are switched in such a fashion that the two counter propagating light pulses in the ring are never in an activated optical amplifier diode at the same time.

Abstract: An electronic library system cabinet having a ring bus architecture with a high reliability backplane wherein the electronic library system includes a plurality of slots for receiving a plurality of modules therein. The modules capability of determining whether the adjacent slot is occupied by a module and alternately directing output information from the module onto a return bus if the adjacent slot is unoccupied or onto an intermodule connection line if the adjacent slot is occupied by a module.

Abstract: An avionics line replaceable unit (LRU), of the type having numerous electronic circuit cards disposed therein in a parallel fashion. The cards being securely held in place when the cover of the LRU is screwed on thereby actuating a spring which transfers force to the circuit cards.

Abstract: A system for monitoring, reporting, encouraging and rewarding proper operation of a vehicle from a fixed location including the appropriate selection of speed sensor, tacometer, fuel flow sensor, gear shift position sensor and brake pedal pressure sensor coupled to a performance monitor which compares the information from the sensors with predetermined acceptable ranges and issues an excess report when the sensed signals exceed the predetermined ranges, a receiver/transmitter for transmitting the excess report to the fixed location where a decision regarding whether to issue a driver bonus reward is made and communicated back to the receiver/transmitter which is coupled to a printer, display/keyboard on board the vehicle for printing a bonus check or notification reward in response to the determination received from the fixed location.

Abstract: A automated miniature fluorescent lamp processing station is disclosed which is used to fabricate miniature fluorescent lamps. The system includes: flow-through gas processing to enhance buffer gas purity, monitoring of the temperature of every lamp in a batch during processing to permit accurate determination of required bus buffer gas fill pressures, real-time determination of target filled pressure at the lamp temperature processing by use of a gas law algorithm and use of microprocessor interfaced sensors and transducers to effect the high level of automation typically required to fabricate avionics grade lamps.

Abstract: An apparatus and method for improving the capture performance of frequency and phase locked loops. The invention permits improved capture performance while, at the same time, maintaining the signal-to-noise ratio performance of the loop while the loop is tracking. The invention estimates the transient response of an automatic control loop. This estimate is used to control elements added to a PLL to accelerate acquisition, and eliminate the noise contribution of those added elements while the loop is tracking. The system uses the variation in the gradient of the loop transient response to derive an estimate of the loop's distance from lock. The system then uses this estimate to control loop parameters which affect the loop's acquisition.

Abstract: A system and method for monitoring and recording the mileage a truck travels within a particular state including a GPS receiver, an odometer, and a memory device which contains state boundary information and a processor for determining on a continual basis whether the positioned information received from the GPS receiver is in a particular state boundary and for recording mileage of the truck when the position and state boundary comparison determines that a change in state boundaries has occurred. Additionally, a storage device for storing the data output by the processor which includes the desired mileage within a particular state information is included.

Abstract: An improved flight control system with an enhanced unified graphic mistrim indicator where the flight control computer provides signals to a single mistrim indicator wherein the signals represent the status of the control surfaces of the aircraft and the mistrim indicator displays a single movable reference marker, which is caused to be translated vertically in the event of pitch mistrim, is caused to be rotated right or left in the case of roll mistrim conditions, is caused to be translated right or left in the case of yaw mistrim conditions or is caused to be moved in a combination of ways either translating vertically, horizontally or rotating in order to represent a combination of pitch, roll or yaw mistrim.

Abstract: A method and apparatus for uniform application of a coating of fluorescent phosphors to tubes that have been bent into a serpentine shape, which includes dragging a hose and phosphor spray nozzle through the bends of the serpentine tube, thereby depositing a phosphor layer throughout the serpentine tube.

Abstract: A liquid crystal display having enhanced viewing brightness and brightness uniformity which utilizes a sculptured diffuser having a varied thickness characteristic where the thickness of the diffuser is reduced in areas where brightness of the display device is desired.