Abstract: An eLORAN receiver may include an antenna and eLORAN receiver circuitry coupled to the antenna. The antenna may have a ferromagnetic core including a ferromagnetic medial portion and ferromagnetic arms extending outwardly from the ferromagnetic medial portion, a respective electrically conductive winding surrounding each of the ferromagnetic arms, and an electrically conductive patch element adjacent the ferromagnetic core.

Abstract: An adjustable high resolution timer (100) for synchronizing a local clock to an external reference clock includes frequency offset acquisition and compensation unit (110) configured to acquire a frequency offset difference between the local and external reference clock and to generate frequency adjustment signals based on the frequency offset difference; a time drift tracking and adjustment unit (120) configured to continuously monitor the local and external reference clocks for phase offset differences therebetween and to generate timing adjustment signals based on the phase offset difference; a nanosecond timer core unit (140) configured to generate a frequency and phase adjusted nanosecond timer output signal in response to the frequency adjustment signals and timing adjustment signals; and a pulse generation unit (130) for generating a plurality of output pulse signals that are synchronized with the external reference clock in response to the frequency and phase adjusted nanosecond timer output signal.

Abstract: A system and method involve using sferic signals to synchronize clocks and/or determine relative receiver positions within a communications network. A sferic signal is detected, encoded, and then identified. A time-difference-of-arrival (TDOA) for the sferic signal is then calculated. A clock error estimate is determined from the TDOA. The clock error estimate is then used to synchronize clocks and/or determine relative receiver positions.

Abstract: A method and system are provided for converting an enhanced Long Range Navigational (eLORAN) signal to a Precision Time Protocol (PTP) signal. Network devices can be located within buildings and not have access to a GPS signal directly from a GPS satellite. Network devices may also be located in a line of sight of a GPS satellite but may lose the GPS signal. An adapter is provided that takes an eLORAN signal, when a GPS signal is lost or not available, and converts the signal into a PTP and other signals to act as timing, synchronization, and syntonization inputs into the network devices. In some cases, the network devices can have a PTP client to receive the PTP signal, one pulse per second signal, and a ten (10) megahertz frequency signal. In other cases, the network devices do not have a PTP client, but can receive a time of day message, one pulse per second signal, and the 10 megahertz frequency signal.

Abstract: Methods and systems are disclosed for radio positioning of a vehicle using a virtual positioning reference established by logging a known position of the vehicle together with a local time that a first instance of a predictably repeated code word is received from an opportunistic terrestrial radio transmitter. During movement of the vehicle to a second, unknown position, a local clock is used to determine the time difference between when the virtual positioning reference is predicted to receive a second instance of the code word and when the vehicle actually receives the second instance of the code word, thereby providing positioning information when traditional navigation signals such as GPS are not available. The radio positioning information is then used to initiate an action such as recording the location information for future retrieval by a user, and/or controlling the movements of an autonomous vehicle.

Abstract: An arrangement for modifying a printed circuit antenna of the type used in mobile communication devices includes introducing one or more discontinuities into a printed circuit pattern of the antenna so that it is not activated at undesired frequencies. Examples of discontinuities include localized narrowing the printed circuit strip, localized widening of the printed circuit strip and localized changing of the shape of the printed circuit strip.

Abstract: A variable-delay-time control system for a motor is provided. The system includes a control unit, a driving unit, and a motor. The control unit is used to output at least one control signal according to at least one predetermined signal, and the control signal has a variable delay time. The driving unit is connected to the control unit, and is used to receive the control signal and generate a driving signal. The motor is connected to the driving unit, and conduction time of the motor is controlled according to the driving signal and the variable delay time. With the variable-delay-time control system of the present invention, the delay time of the control signal is variable, so the motor can operate at a high efficiency (for example, at a reduced current). Moreover, as the variable-delay time can be adjusted according to the predetermined signal, the motor can operate at a high efficiency in different operating states, thus improving the overall efficiency of the motor.

Abstract: Location systems and methods are implemented using a variety of arrangements and methods. Using one such system location information is provided in response to a utility-line arrangement propagating signals that represent a wireless radio-frequency (RF) communication originating from one or more remote transmitters. The system includes a receiver circuit communicatively coupled and responsive to the utility-line arrangement. The system also includes a signal-processing logic circuit, communicatively coupled and responsive to the utility-line arrangement. The signal processing logic circuit is arranged to derive location information from characteristics of the signals that are indicative of a location of the receiver circuit relative to the remote transmitters.

Abstract: Apparatuses are described and disclosed which operate in a first mode to receive non-position signals, for example FM radio signals, and in a second mode of operation to receive land-based position signals, for example LORAN signals.

Abstract: A method and device is provided for transmitting location-based text messages between electronic devices. A mobile electronic device can determine a device's location, create a map of that location, create a text message, embed the map in the text message and transmit the text message to a recipient. The device can also transmit or create navigational directions and update the map and the directions in real time.

Abstract: A system is provided for underground mapping, location determination and communications utilizing existing LORAN transmitters and a subterranean H-field antenna coupled to a conventional LORAN receiver. The result is an underground LORAN grid from which mapping and location can be ascertained as well as terrestrial-to-subterranean communications using the LORAN bit streams. Subterranean-to-terrestrial communication is established by a low-frequency handheld transmitter using repeat processing to transmit digital data from the subterranean location to the surface of the earth using modulated H-field waves.

Abstract: A method and radio navigation system compass apparatus for determining true north or azimuth or orientation of a vehicle or the like by the use of integrated Loran and satellite radio navigation receivers employing crossed-loop H-field antennas for the Loran reception, or the use of at least three Loran type transmitter, or two Loran type transmitter and a synchronized clock for determining both position and azimuth.

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: A method and apparatus for increasing the potential digital bit data rate potential for communication-to-be-added to Loran-C radio-frequency pulse navigation transmitters and the like without affecting the navigation capability and integrity of the system, involving frequency-sweeping the pulse carrier frequency between critical lower and upper limits with respect to the pulse carrier frequency during the parts of each pulse following the initial part used for navigation timing.

Abstract: A signal handling device enables a data transmission between a plurality of position measuring devices and a master unit. The signal handling device includes a main communications port for communicating with a master unit via a data bus and a measurement port for communicating with a position measuring device. The signal handling device also includes an extension port for connection to an intelligent slave unit so as to enable communication with a plurality of position measuring devices via the said slave unit. In addition, the signal handling device also includes a data processing unit which is capable of managing data traffic between the main communications port, the measurement port and the extension port.

Abstract: Apparatus is provided in an aircraft to convert signals from a Universal Navigation System such as LORAN to signals compatible with the standard Omni Bearing Selector (OBS) in the aircraft. The apparatus allows a visual bearing to any destination to be provided for the navigator.

Abstract: A method is disclosed for encoding signals for transmission to provide signals which simultaneously have specifiable autocorrelation properties and low predictability. To enhance the accuracy of time of arrival measurements in the presence of either noise or multipath due to skywaves in systems such as LORAN, the coding method provides for low autocorrelation function values at time offsets approximately equal to the expected delay between direct waves and skywaves. This is accomplished by constructing the codeword which is used to encode the signal, from an Nth difference constant ratio codeword, where the expected time delay is equal to N-bits. The constant ratio codewords and the transmitted codewords are both pseudo-randomly generated, resulting in a transmitted signal having very low predictability to an unintended recipient, thereby considerably reducing the effectiveness of attempts at jamming or other electronic countermeasures attacks.

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: A low cost electronic navigation system including a Loran receiver and a marine radar unit adapted to receive vessel position information from the Loran. A computer within the radar unit uses successive Loran outputs to display vessel heading and the bearing of objects of interest such as other vessels or waypoints in graphic and numeric form. The navigator may accurately determine the bearing of such objects of interest in magnetic or true form. Other modes are of particular use when the navigator is interested in using the system to maintain a desired course, to avoid obstacles, or to determine if and by how much he must change his present course to return to the desired course.

Abstract: A method for detecting lightning as an electrical atmospheric disturbance and for providing an indication of the geographic position of that disturbance includes the stationing of at least three receivers at known geographic locations in spaced relationship to each other. Signals are encoded at each of the receivers representative of the time of arrival of an electrical indication of an emission from the lightning strike, in relation to a common timing source. All of the encoded signals are transmitted to a central facility and thereafter processed for deriving the position of the lightning strike irrespective of whether the position of the lightning occurred within or outside the perimeter bounded by the three receivers. The system is synchronized with the U.S. Coast Guard LORAN navigation network, and includes various features which permit a more accurate analysis of lightning position.

Abstract: A stolen object location system having a base station, a location network and an object unit which is associated with the object to be located. The location system is capable of operating in a plurality of different location modes ranging from simple triangulation to LORAN. The base station, upon being notified that the object has been stolen, will transmit a locate request message to the object unit specifying the location mode to be used and the transmission frequency of the object unit's transmitter. An electronic control in the object unit will control the operation of the object unit's receiver and transmitter in accordance with the location mode and transmission frequency specified in the locate request message.