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Match Document Document Title
7391369 Method of and apparatus for eliminating quadrature-generated signals in magnetic cross-loop antennas  
A technique for reducing radio frequency signal navigation errors in systems such as Loran-C and the like, comprising the use of an orthogonally crossed pair of antenna windings on a ferrite...
6928265 METHOD OF AND APPARATUS FOR IMPLEMENTING HIGH SPEED DATA COMMUNICATION BY PHASE (FREQUENCY) MODULATION OF LORAN-C NAVIGATION SYSTEM USING SOLID-STATE PULSE TRANSMITTERS AND HIGH-POWER SOLID STATE SWITCHING FOR DYNAMIC ANTENNA TUNING  
A frequency-hopping intrapulse frequency modulation Loran-C navigation pulse technique, preferably using a flat-topped pulse shape and a novel 16-ary phase hopping scheme, and a novel improved...
5796366 Method of and apparatus for position location and tracking of a vehicle or the like by the reception at the vehicle of pulsed radio navigation signals as of the Loran-OC type and the like, with an autonomous loop antenna-receiver  
This disclosure deals with processing radio-frequency navigation signals, particularly Loran-C signals, from crossed loop antennas (H-field antennas) by shifting the signal phase from two loops to...
5635940 Communication configurator and method for implementing same  
A method and apparatus for communication configuring in digital equipment based on the location of the equipment includes a mechanism determining the location of the digital equipment and a...
5563611 Method of and apparatus for integration of Loran-C and satellite navigation system (SNS) technologies for improved system accuracy, availability and integrity  
A method of apparatus for integrating Loran-C and satellite navigation system technologies in a manner in which the Loran-C navigation signal transmissions are further modulated to provide a...
5363112 Noise suppression processor for a carrier tracking loop  
A noise suppression processor maintains a carrier tracking loop in a receiver in lock in the presence of high noise levels to permit the receiver to measure range changes from a remote transmitter...
5311195 Combined relative and absolute positioning method and apparatus  
A navigation system comprising a relative positioning system (RPS) with dead reckoning and map matching and an absolute positioning system (APS) is provided and operated in such a manner that APS...
5278568 Method of and apparatus for two-way radio communication amongst fixed base and mobile terminal users employing meteor scatter signals for communications inbound from the mobile terminals and outbound from the base terminals via Loran communication signals  
A method of and apparatus for two-way radio meteor scatter communication amongst mobile transceiver-equipped terminals and fixed meteor scatter base terminal(s) that comprises communicating high...
5220333 Method and apparatus for determining universal coordinated time from Loran-C transmissions  
A method and apparatus for determining Universal Coordinated Time from Loran-C transmissions at at least two Group Repetition Intervals. With time known to within a few seconds of Universal...
5193215 Location signalling device for automatically placing a radio distress call  
A location signalling device sends a radio distress call giving the precise location coordinates of a person in distress automatically once it is activated without the need for anyone to operate...
5181041 Accurate location system using transponded and correlated LORAN signals  
An accurate location system 10 for use in locating the position of a tracked unit 16 having at least a first and a second transmitter 14, 22 for propagating at least first and second signals and a...
5173690 Passive ranging system utilizing range tone signals  
A passive ranging system for determining the slant range from a ground station to a drifting radiosonde. In one embodiment, the ground station receives meteorological data ranging and internal...
5105196 Loran-C alignment method  
An alignment procedure to insure the proper and faithful reproduction of the automatic control loop SERial DAta (SERDA) instructions issued by the Pulse Amplitude and Timing COntrol Unit (PATCO)....
5032845 Vehicle locating system with Loran-C  
The location of a vehicle having an assigned serial number is determined at a location remote from the vehicle with a system including a central master station and plural local networks, each...
4999638 Apparatus and method for synchronizing the signal averaging clock of a Loran C. receiver to the clock of a Loran C. transmitter  
Radio signals containing Loran C pulses from stations from a desired chain are amplified, filtered and ensembled averaged in an acquisition memory which is accessible by a controlling...
4959655 Method for the radiolocation of a vehicle carrying a receiving device, by measuring the differences between the times for receiving radio-frequency signals, and receiving device for carrying out this method  
A method and a device for the radiolocation of a vehicle carrying said device, wherein the radiolocation is performed by measuring the differences between the times for receiving radiofrequency...
4914436 Ground proximity approach warning system without landing flap input  
A ground proximity warning system is disclosed which can recognize when an aircraft is on a final approach to an airport without utilizing a landing flap signal input. Airports together with the...
4888594 Loran-C receiver module  
A Loran-C Receiver Module is provided which utilizes minimum rate sampling means as well as a homodyne receiver at the front end of the Receiver Module to mix down the Loran signal to base band....
4833477 Emergency vessel location system  
An omega, loran or satellite navigation receiver is provided with a speech synthesizer coupled to its latitude/longitude output which is in turn coupled to a transmitter which transmits the...
4821038 Method of and apparatus for Loran-C message communication with reduced skywave navigation location errors and the like  
A Loran-C communications technique and system are disclosed involving appropriate encoding of communication messages and logical multiplication and inversion of encoded signals prior to phase...
4814771 Apparatus and method for receiving and proessing Loran signals  
A radio signal containing Loran C pulses from stations of interest is received and periodically sampled to convert the input signal to sample data. The data is assigned to memory locations within...
4812851 Radio receiver with automatic interference cancellation  
Undesired, intefering narrow band received signals in a radio receiver are automatically cancelled by a cancellation system including a variable narrow band pass filter that separates a sample of...
4804964 Loran-C signal receiving apparatus  
A Loran-C signal receiving apparatus which achieves accurate measurement of the location of the apparatus without error due to a well-known cycle slip phenomenon. In the Loran-C signal receiving...
4800391 Method of and apparatus for message communication on Loran-C navigational signal broadcasts and the like with reduced navigation errors  
In a Loran-C message communication system a method of obviating errors in navigation locking caused by sampling reception at the conventional symmetrical pulse modulation time intervals in advance...
4791422 Methods of and apparatus for measuring time of arrival of remote Loran-C and related signals and effective time of transmission of local signals at transmitter sites  
A method of and apparatus for measuring time of arrival of remote Loran-C and related signals and effective time of transmission of local signals at Loran transmitter sites through use of a...
4774518 Loran-C signal phase tracking apparatus  
An apparatus receives Loran-C pulses and tracks the phase of each received Loran-C pulse received from master and secondary stations. The apparatus comprises: (a) a phase comparator (12) for...
4743912 Method of and apparatus for reducing cycle slippage errors in Loran-C and similar radio-frequency signal reception, particularly in vehicles undergoing acceleration  
Method and apparatus of obviating cycle-locking slippage errors in reception of Loran-C and similar radio-frequency signals covered by receiver location acceleration effects and other distortion...
4670759 Automatic Loran-C signal detecting apparatus  
An automatic Loran-C signal detecting apparatus samples a received signal at a constant high sampling frequency of which the Loran-C carrier frequency is a harmonic. The polarity of the sampled...
4651157 Security monitoring and tracking system  
A method and apparatus for positively indicating the position of a land-based vehicle, a marine vessel or an aircraft, utilizing a security system provided in the secured mode of transportation...
4633260 Loran-C signal receiving apparatus  
A system for detecting a particular cycle of a received Loran-C signal in a Loran-C receiving apparatus, recognizes the envelope of a carrier wave in each Loran-C pulse for a predetermined...
4631543 Method and apparatus for reducing the effects of impulse noise in Loran-C receivers  
The effects of impulse noise on the operation of a microprocessor-controlled Loran-C receiver are reduced by muting or attenuating the received signals in the front end of the receiver ahead of...
4595927 Loran C cycle slip reduction technique  
In accordance with the present invention, there is provided a Loran C cycle slip reduction technique that consists of sensing the signal to noise ratio and narrowing the phase locked loop...
4594594 Loran signal receiver  
A received signal containing a loran-C signal is periodically sampled. The sampled data values in two successive periods of the loran-C signal are stored in corresponding first and second period...
4584580 Apparatus for rejecting jamming waves  
A variable-narrow-band rejection filter is inserted in a reception signal path for rejecting a jamming wave. Signals at input and output terminals of the narrow-band rejection filter are picked up...
4539566 Automatic interference canceling apparatus  
An auto notch system which automatically "notch" filters up to four interference signals (interferers) in the band from 50 KHz to 150 KHz comprises a signal detector, an adjustable notch filter, a...
RE31962 LORAN-C navigation apparatus  
LORAN-C navigation apparatus is disclosed wherein digital circuitry and a microprocessor is are used to automatically identify LORAN transmitting stations and makes make standard hyberbolic...
4513378 High-accuracy navigating apparatus with step-driven projected chart  
A small fraction of the area shown in an ultraminiature color transparency of a standard navigating chart is projected onto a viewing screen, and the transparency is moved by a precision...
4468668 Method for processing signals in a navigation receiver  
A method for processing navigation signals received by a LORAN-C receiver to lessen the effects of noise on the navigation data provided to the receiver user. Time of signal arrival information...
4459667 Guidance method and system for an automotive vehicle  
A guidance method and system for an automotive vehicle which switches from an electronic navigational signal method to a dead reckoning method when any of the field strengths of three navigational...
4445223 Apparatus and method for determining the presence and frequency of a periodic signal  
An apparatus and method for determining the period and frequency of a signal intefering with a desired Loran C signal are provided. A sample of the interfering signal is generated at a time...
4435711 Radio telephone with position transmission capability  
A communications link having a position capability responsive to either a manual or remote control actuation. In one embodiment, a remote carrier has a navigation system for outputting signals...
4416017 Apparatus and method for attenuating interfering signals  
A method and apparatus for attenuating an interfering signal corrupting a desired Loran C signal is provided. An interfering signal sample is determined which occurs at the peak of the...
4392138 Apparatus and method for detecting and inhibiting signals interfering with a Loran C signal  
An interference rejection apparatus is provided which samples the Loran C signal at selected pulse tracking reference points. The Loran C samples are separated into even and odd groups by...
RE31254 Self calibration of a LORAN-C navigation receiver  
A method for self calibration of a LORAN-C navigation receiver utilizing a microprocessor is disclosed wherein the time difference of signal arrival of master station pulse trains from a LORAN-C...
4377866 Time multiplexed Loran signal processing apparatus  
Loran C signal processing apparatus is provided which employs a single signal channel or path to process and sample Loran C RF signals and envelope derived Loran C RF signals which in conventional...
4325067 Method and apparatus for removing noise in a LORAN-C navigation receiver  
Noise generated in the front end of a LORAN-C receiver that causes noise bias interfering with carrier cycle detection is effectively removed by periodically shifting the phase of all received...
4325068 Loran-C signal processor  
A Loran-C receiver signal processor is disclosed which processes radio frequency Loran-C signal pulses on a point-by-point, cycle-by-cycle basis to provide the ability to locate on each pulse a...
4300139 Loran-C navigation apparatus  
A Loran-C navigation receiver is disclosed wherein digital circuitry and a microprocessor is used to automatically identify Loran transmitting stations and makes standard hyberbolic navigation...
4214245 Loran receiving apparatus  
A Loran receiving apparatus is repeatedly switched by the actuation of a display mode changeover means between the state of displaying a plurality of measured time differences on a display in a...
4195299 Loran-C system monitor circuit  
A Loran-C antenna and coupling circuit therefor are disposed at a given site, the antenna and coupling circuit therefor being capable of both transmitting and receiving. A first circuit is...

Matches 1 - 50 out of 86 1 2 >