Abstract: An RF PNT system may include LORAN stations. Each LORAN station may include a LORAN antenna, and a LORAN transmitter coupled to the LORAN antenna and configured to transmit a series of LORAN PNT RF pulses having a time spacing between adjacent LORAN PNT RF pulses. One or more of the LORAN stations may include a message embedding generator coupled to the LORAN transmitter and configured to generate message RF bursts based upon an input message, and with each message RF burst being in the time spacing between respective adjacent LORAN PNT RF pulses.

Abstract: A LORAN device may include a housing, and an electrically short LORAN antenna carried by the housing. The LORAN device may have a LORAN receiver carried by the housing and coupled to the electrically short LORAN antenna, and an RF crystal resonator coupled to the electrically short LORAN antenna so that the electrically short LORAN antenna is forced to a resonant condition for a LORAN receive signal.

Abstract: A sonar transmit array (11), comprising: a plurality of transmitters configured to generate an acoustic sonar signal, wherein at least one of the transmitters is a polyvinylidene difluoride, PVDF, piezoelectric device configured to generate at least part of the acoustic sonar signal. Some embodiments, include a receive array (12) and the associated receive array circuitry (14).

Abstract: An enhanced LOng RAnge Navigation (eLORAN) system may include a plurality of eLORAN transmitter stations, each configured to transmit respective eLORAN signals at different frequencies. An eLORAN receiver device may be configured to receive the respective eLORAN signals at different frequencies from each of the eLORAN transmitter stations, determine a correction factor based upon the received respective eLORAN signals, and apply the correction factor to determine a geographical position of the eLORAN receiver device.

Abstract: A method for determining an instantaneous phase difference between time bases of at least two location anchors for a desired point in time (t), each of the location anchors having transmitting and receiving access to a joint broadcast transmission medium and a respective time base for measuring time, wherein a first of the location anchors broadcasts a first broadcast message at least twice; the first location anchor and at least a second of the location anchors receive the first broadcast messages; the second location anchor broadcasting a second broadcast message at least twice; and the second location anchor and at least the first location anchor receive the second broadcast messages. The location server calculates the instantaneous phase difference from a determined first and second clock model functions and from a time elapsed between a reference point in time and the desired point in time t.

Abstract: A display device includes a display panel, a sensing circuit, and a compensation circuit. The sensing circuit senses a current generated by a pixel of the display panel. The sensing circuit includes an integrator circuit, a comparator, and a counter. The integrator circuit is initialized to have a first reference voltage as an output. The output of the integrator circuit changes with a rate according to the sensed current. The comparator compares the output of the integrator circuit to a second reference voltage. The counter determines a time for the output of the integrator circuit to reach the second reference voltage from the first reference voltage. The compensation circuit receives the determined time and determines a compensation amount from the received time. The compensating circuit further compensates a display voltage for the pixel by the determined compensation amount in a subsequent display frame of the display device.

Abstract: A radar apparatus includes: a radar transmitter transmitting a radar signal; and a radar receiver receiving a reflection wave signal being a reflection of the radar signal on a target. The radar transmitter includes: a radar transmission signal generator that generates the radar signal composed of a transmission code with each sub-pulse given a predetermined phase shift; and a transmission radio unit that transmits the radar signal generated by the radar transmission signal generator in a predetermined transmission cycle. In radar signals transmitted by the transmission radio unit in a predetermined number of transmission cycles, code imbalances of transmission codes are included in all of four quadrants of the IQ plane. Each of the code imbalances is an imbalance between the positions where a plurality of sub-pulses constituting a transmission code included in a radar signal transmitted in each of the transmission cycles are mapped on the IQ plane.

Abstract: Aspects of the present disclosure relate generally to systems and methods for assessing validity of a map using image data collected by a laser sensor along a vehicle path. The method may compile image data received from the laser sensor. The map subject to assessment may define an area prohibiting entry by a vehicle.

Abstract: Based upon the present location and historical usage at that location, the technologies disclosed herein select a wireless peripheral device (e.g., a printer, monitor, keyboard) for wireless connection with a portable device (e.g., a laptop computer or tablet). This Abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: A timer unit to counts a current date and time, a current position acquisition unit to acquire a current position, a determination unit to determine a time zone in which the acquired current position is included, and a local time acquisition unit to calculate local time corresponding to a time difference of the time zone determined by the determination unit are included. When a boundary line of the time zone is along a coastline, the determination unit changes the boundary line from the coastline to a side of a sea in a predetermined distance range and determines a time zone.

Abstract: Systems and methods utilize a distributed server network to allow for the optimization of the upload of a data stream from a computing device. Performance metrics are estimated for different network paths from the computing device to a variety of entry servers in the distributed server network. Based on the estimated performance metrics, one or more entry servers are then selected to receive the data stream from the computing device. As a result, the systems and methods described herein allow for high quality upload performance which addresses the first mile vulnerability issues of the data stream. The distributed server network can then transmit copies of the data stream in real-time to other computing devices.

Abstract: In an embodiments a method of providing a local access number to a subscriber may include receiving subscriber locale information indicating a location of a subscriber, mapping the subscriber locale information to one or more local access numbers, identifying, from the one or more local access numbers, a local access number corresponding to the subscriber locale information and transmitting the identified local access number to the subscriber's mobile device.

Abstract: A mobile communication device receiver for receiving a communication signal of a base station via a carrier includes a filter, a scanner and a first controller. The scanner is configured to scan a frequency range in order to determine a spectral distribution of interference within and/or adjacent to the carrier. The first controller is configured to adapt a passband characteristic of the filter based on the spectral distribution.

Abstract: 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 cross, tuned to the carrier radio frequency to generate from the received signals both in-phase and quadrature circulating current components, and providing for the eliminating only of the quadrature current components.

Abstract: 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 high-power solid-state switch for dynamic antenna modulation tuning.

Abstract: 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 be in quadrature with respect to each other and adding them together to achieve omnidirectivity of the antenna pattern during the acquisition mode; using the stronger signal of the two during the cycle selection mode to determine the polarity of the received signals; and calculating the relative bearing angles on transmitting stations to determine, with measured bearing, the orientation of the loop antenna with respect to these stations.

Abstract: 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 mechanism configuring a communication channel of the equipment based on the location. The location may be determined using a Global Positioning System, Global Paging System, or similar wireless communication system, or by connection to a wired network. User input may also be used in determining, in part or in whole, the location of the digital equipment. Once the location of the digital equipment has been determined, the communication channel for the digital equipment is configured based upon the location using configuration data stored with the digital equipment.

Abstract: 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 communications signal and a supplemental navigation signal, timed to provide additional position information, and used to smooth user position and velocity data between augmentation data messages and between adding and deleting or losing satellite contributing signals.

Abstract: 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 in noisy environments. The noise suppression processor is connected in the carrier tracking loop between the phase detector which produces the loop error signal and the loop filter. The noise suppression processor has a cubic-limiter transfer function to provide nonlinear amplification of the loop error signal while limiting the amplified error signal to predetermined maximum and minimum values.

Abstract: 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 position information is used for updating RPS position and contour of equal probability (CEP) information as required. The APS may comprise a Loran-C or a global positioning system (GPS). Different criteria are used for resetting the RPS depending on whether or not the navigation system comprises a Loran-C or a GPS due to the different levels of precision of the Loran-C and the GPS. When the RPS is reset or updated, it is updated to the current APS position with its offset, if any. Its contour of equal probability (CEP) may also be adjusted.

Abstract: 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 volume point-to-point inbound information from the mobile terminals to the base terminal(s) and outbound information from the base terminal(s) to particular mobile terminals by radio meteor scatter, and broadcasting outbound information from the base terminal(s) to many mobile terminals by supplemental Loran communications short messages modulated upon Loran radio positional and navigation transmissions.

Abstract: 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 Coordinated Time, and position known to within approximately five miles, the present invention permits time transfer substantially to Universal Coordinated Time by receiving first and second Loran-C transmissions at first and second Group Repetition Intervals. Then, a coincidence interval between the two Group Repetition Intervals is calculated, and time is transferred to coincide substantially with Universal Coordinated Time based on the calculated coincidence interval.

Abstract: 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 an associated radio transmitter. The device includes a microprocessor controller, a digital location data input, a keyboard, a voice input, an LCD display, a clock/timer, a digital memory, and a voice synthesizer output which provides the distress call in audio voice signals to the microphone input of the radio transmitter when an activating switch is pressed.

Abstract: 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 master station 12 for receiving and storing the first and second signals, respectively. The tracked unit 16 receives and operates on the first and second signals from the first and second transmitters 14, 22, respectively, for providing third and fourth signals which are transponded to the master station 12. A correlation detector 40 located within the master station 12 receives and cross-correlates the transponded third and fourth signals with the stored first and second signals within the master station for determining the additional times of flight (.tau.) of the third and fourth signals transponded to the master station. The locus of points of constant (.tau.

Abstract: 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 temperature signals from the radiosonde. The data signals are read out as ambient conditions of the atmosphere and the range signal is phase-compared to a reference signal at periodic intervals. Changes in frequency due to temperature fluctuations in the radiosonde components are factored into the phase-comparison, and the resultant change in phase represents movement of the radiosonde. In another embodiment the range tone from a remote broadcast station is retransmitted by the radiosonde and received at the ground station simultaneously with the same tone directly from the broadcast station. The phase lag is measured and coupled with measurements of direction from the ground station to the radiosonde, and with the distance between the ground station and the broadcast station for determining the slant range.

Abstract: An effusion source for epitaxial deposition plants wherein molecular vapor beams are directed towards a substrate to be grown in ultrahigh vacuum environment, which has a first tube, which is airtightly closed at one end by flanges allowing the passage of vapor inlet tubes and is equipped at the the other end with baffle plates and a nozzle for mixing vapors and shaping the molecular beam. A second tube, coaxially joined to the first tube, allows an interstice at ambient pressure and temperature to be obtained in the zone of the vapor mixing and molecular beam shaping, wherein a heating can be located.

Abstract: 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). This reproduction takes place during high level, multipulsed, radio frequency energy transfer to the antenna system. The precise reproduction of the low level digital pulse shape and timing instructions will insure that the transmitter set is operating within the constraints of the International Telecommunications Union for radio transmissions and the specifications which govern the original design during "automatic operation" at a specified Envelope to Cycle Difference (ECD). The alignment procedure once accomplished allows for a simplified monitoring technique, to insure continued proper operation. This monitoring and correction routine can be accomplished using personnel of less technical expertise and test equipments of less complexity and cost.

Abstract: 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 having a local master station in a bi-directional communication link with the central master station. Each vehicle includes a receiver for Loran-C emissions, a transmitter for modulating a first carrier having a frequency much higher than the Loran-C emissions with pulses having time positions corresponding with and synchronized with Loran-C pulses as the received Loran-C emissions, and a receiver for a second carrier having a frequency much higher than the Loran-C emissions. The first carrier is modulated by vehicle serial number signals. The carriers are transmitted via radio links between the local master station and vehicle. The local master station responds to the first carrier to detect the time difference between pulses modulating the first carrier to determine vehicle position.

Abstract: 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 microprocessor. By staggering the ensemble averaging of the first four pulses in a station pulse group in time with respect to the last four pulses of the same pulse group, cross correlating the composite pulses formed by averaging the first four and last four pulses of the station pulse group with the help of the microprocessor provides time skew information which is used to adjust the receiver's master clock to align it with the clock of the transmitter. By varying the amount of time stagger, an ever finer resolution adjustment range is achieved. When the staggered averaging cycle times would exceed the time between successive ensemble averaging cycles without stagger, then successive ensemble averaging cycle time is employed for master clock adjustment.

Abstract: 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 signals transmitted by two transmitting stations geographically far away from each other, of at least one group of stations, each group comprising at least two transmitting stations including one master transmitter-forming station and at least one slave transmitter-forming station controlled by the master transmitter, each station transmitting a series of close electric pulses which are time-shifted in a predetermined way with respect to the series of pulses transmitted by the other stations, during a predetermined period of time, the method being characterized in that the acquisition of the signals and the measurement of the difference between the times for receiving the signals transmitted by transmitting stations of two different groups are performed in a unique receiving channel by performing the acquisitions and m

Abstract: 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 surrounding terrain topography are modeled by a simple geometric shape, such as, an inverted truncated cone, and stored on-board the aircraft. The system uses navigational data to determine the distance of the aircraft from the geometric model. Once the aircraft is determined to be within the area defined by the geometric model, the system provides an enabling envelope indicative that the aircraft is on a final approach for enabling various ground proximity warning systems. Also disclosed is a system for altering the enabling envelope as a function of the aircraft's alignment with a particular runway.

Abstract: 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. Once the frequency of the Loran signal is reduced, it is much easier and more economical to perform various functions such as filtering, digitizing, etc. . . . , on the signal.

Abstract: 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 latitude and longitude along with a "mayday" indication on an emergency channel when an emergency button is depressed on the unit. The emergency button turns the power on for the navigation unit and bypasses all functions except those relating to the production of a lat./lon. signal. The emergency button also activates the synthesizer after determining that the navigation unit has obtained lock. Upon the obtaining of lock a repeat timer produces repeated dump pulses to the speech synthesizer which modulates the transmitter to transmit the "mayday" indication plus an indication of the latitude and longitude of the vessel. As an option, the vessel name, type and color may be entered into a memory for the speech synthesizer so that the identity of the vessel and its type and color may be ascertained.

Abstract: 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 modulation of the Loran-C pulses, with novel bit-flip connections for producing complementary plus and minus modulation position shifts in the first and third and second and fourth, etc., of the Loran-C pulse groups, and with perfect balance irrespective of the nature of the raw data and irrespective of skywave interference.

Abstract: 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 an acquisition memory at positions in the memory which correspond to specific times within the group repetition interval (GRI) of the Loran chain of interest. A GRI counter assigns the locations in the memory to which the data are written and cycles the memory after the completion of each GRI so that new data corresponding to a new set of pulses from the master and secondary stations of the Loran C chain will be assigned to essentially the same memory locations as data acquired during a previous GRI. The new data is ensemble averaged with the old data contained in the memory locations and the averaged data stored back in the memory.

Abstract: 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 the undersired signals from the total received signal, reverses phase of the sample and combines it with the total received signal, substantially cancelling the undesired signals therein. In a Loran-C receiver, desired beacon signals in the band 90 to 110 KHz are received aling with narrow band interfering (undesired) signals. During a "cancel mode," a narrow band of the total received signal is sampled by a variable narrow band pass filter and the narrow band sample is reversed in phase and then combined with the total received signal to cancel the undersired signals therein.

Abstract: 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 apparatus, a pulse tracking a particular cycle of a carrier wave of the received Loran-C signal is generated, a frequency at which the tracking pulse is generated by a pulse generator (in a PLL circuitry) is monitored and when a frequency error of the generator is derived on the basis of a tracking error of the tracking pulse with respect to the received Loran-C signal, the frequency of the pulse generator is corrected on the basis of the derived frequency error. The apparatus can thus assure a phase tracking of the received Loran-C signal and assure accurate measurement of the location.

Abstract: 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 of and in delay from the normal transmission interval, through rendering the pulse modulation assymetrical to a degree that compensates for different cycle amplitudes at sampling points above and below the desired sixth zero crossing used for navigation position determination.

Abstract: 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 simulated Loran signal locally generated and coupled into the receiving antenna system that receives the remote signals in a time slot not occupied by the local transmitted signal.

Abstract: 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 comparing the phase of the Loran-C pulse received from each transmitting station with that of a comparison signal; (b) a phase locked loop circuitry (16) for generating the comparison signal at a given integral multiple of the repetition rate of the Loran-C signal; (c) an S/N ratio detection circuit (14) for measuring the signal-to-noise ratio of the received signal; (d) a loop filter (13) for correcting the timing at which the comparison signal is generated toward coincidence with the phase of the received Loran-C pulse when a given number of phase comparisons by the phase comparator (12) produce results of the same polarity; and (e) a sample number control circuit (15) for adjusting at least one of the given integral multiple and the given number according to the measured signal-to-noise ratio.

Abstract: 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 effects simulating the same, that comprises, receiving the radio-frequency signals and producing data by sampling and tracking the cycles of the signal with a time-constant filter sufficiently fast to accommodate for the largest acceleration to be experienced by the receiver location to avoid cycle slippage in locating a predetermined cycle zero crossing, and independently post-filtering sufficiently slowly to smooth the data and without interaction with said sampling.

Abstract: 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 signal at each sampling frequency cycle is stored in a corresponding memory cell for every two successive periods of the Loran-C signal. All of memory cells are previously loaded with a value m. A control unit determines whether the polarity of the sampled signal is positive or negative and adds +1 to the value m of the memory cell when the sampled signal is positive and adds -1 to the value m of the memory cell when the sampled signal is non-positive. After a given number of Loran-C signal cycles, the accumulated polarity totals are compared to a range around the original value m to detect which memory cells, i.e. which sampling times, coincide with Loran-C pulses. The polarity of the Loran-C pulses thus detected can then be checked to identify the sending station of each group of Loran-C pulses.

Abstract: 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 monitored by a central station. Navigational information transmitted by LORAN-C transmitters or satellite transmitters are received and then retransmitted to the central station which determines the exact latitude/longitude coordinates of the secured mode of transportation. The secured mode of transportation also includes a security panel for monitoring the condition of various parameters. An interface is connected to the security panel and the navigational receiver for coordinating the transmission of information relating to the conditions monitored by the security panel as well as the information received by the navigational receiver before they are sent to a radio for transmission to the central station.

Abstract: 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 duration after the onset of the Loran-C pulse. The system compares the detected envelope to reference envelope data so as to identify where on the actual Loran-C envelope the measured envelope lies in order to identify the particular cycle of the received Loran-C pulse.

Abstract: 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 the receiver gain during a time period which preceeds the start time of the pulses being tracked. The attenuation is selectively removed after the start time of each pulse being tracked to permit the receiver to perform its time difference of pulse arrival measurements in the normal manner. The attenuation is also selectively removed during those time periods in which the receiver performs its envelope slope, skywave/groundwave and other such samplings. The attenuation is provided by a muting circuit which is controlled by a time gate signal that derives from the microprocessor of the receiver.