Abstract: A system for receiving a radionavigation signal, notably in a jammed medium, emitted by a satellite of a satellite positioning system, includes: at least one first multi-correlator and at least one second multi-correlator disposed in parallel and operating respectively at a frequency; filtering means, disposed upstream of said multi-correlators; a delay line, disposed on the branch, between the filtering means and the second multi-correlator; means for sub-sampling at the frequency adapted for sub-sampling the signal transmitted directly and by branching with delay by the filtering means; and demodulation means eliminating the Doppler effect, disposed between the sub-sampling means and the first and second multi-correlators.

Abstract: The present invention discloses a smart antenna system for a portable device. The smart antenna system includes a plurality of directional antennas, disposed at a plurality of positions of the portable device, having a plurality of directional radiation patterns corresponding to a plurality of areas; wherein all of the plurality of directional radiation patterns substantially form an omni directional radiation pattern.

Abstract: A method of measuring the direction of arrival ? of radio signals in the HF band received by a crossed loop antenna includes, in a preparatory calibration phase, acquiring and recording the measurements made by the antenna of a calibration signal which varies in its frequency and bearing angle; and in a measurement phase in which the bearing angle or angles of arrival of signals detected by the antenna is or are determined, acquiring the signals detected in at least one frequency channel, and then, for each frequency channel fi, correlating the acquired signals with the recordings having frequencies close to fi, resulting from the calibration, and determining the direction of arrival of the signals by finding the bearing angle ? for which the maximum correlation is reached.

Abstract: In an example embodiment, there is disclosed herein, an apparatus comprising an interface and location determination logic coupled with the interface. The location determination logic receives data representative of measured signal strengths for a wireless device from a plurality of receiving devices at known locations via the interface. The location determination logic determines an estimated location based on the measured signal strengths and a first transmit power for the wireless device. The location determination logic determines a revised transmit power for the wireless device based on the measured signal strengths from the plurality of devices at known locations and the estimated location. The location determination logic determines a revised estimated location based on the measured signal strengths and the revised transmit power for the wireless device.

Abstract: A method for jointly determining the azimuth angle ? and the elevation angle ? of the wave vectors of P waves in a system comprising an array of sensors, a number of waves out of the P waves being propagated along coherent or substantially coherent paths between a source and said sensors, includes at least the following steps: selecting a subset of sensors from said sensors to form a linear subarray of sensors; applying, to the signals from the chosen subarray, an algorithm according to a single dimension to decorrelate the sources of the P waves; determining a first component w of said wave vectors by applying, to the signals observed on the sensors of the chosen subarray, a goniometry algorithm according to the single dimension w; determining a second component u of said wave vectors by applying a goniometry algorithm according to the single dimension u to the signals from the entire array of sensors; determining ? and ? from w and u.

Abstract: A system and method for improving acquisition sensitivity and tracking performance of a GPS receiver using multiple antennas is provided. In an embodiment, the acquisition sensitivity can be improved by determining the correlation weight of each received path signal path associated with one antenna form a plurality of antennas and then combining the path signals based on their respective correlation weight. In another embodiment, carrier offset correction information of each path signal is individually determined and then summed together to be used for tracking the code phase in a code phase tracking loop. The code phase tracking loop generates an early code and a late code that are used to determine the code phase error. The system includes notch and bandpass filters to mitigate narrowband and broadband noises of a received GPS signal, wherein the digital adaptive filters are switched on periodically or by external events.

Abstract: In embodiments of sync feedback for time to first fix (TTFF), satellite data signals are received from which a geographic position of a positioning-system device can be determined. The satellite data signals each include a time reference and ephemeris data that indicates an orbital position of a satellite. A sync feedback is generated that includes a time-free position fix determined from a satellite data signal before bit sync and/or frame sync of the satellite data signal are obtained. The sync feedback is then utilized as a feedback input to determine the bit sync and/or the frame sync of the satellite data signal.

Abstract: An emergency rescue system and a rescue-information judgment method are disclosed. The emergency rescue system includes a plurality of fixed nodes, a dynamic node and a back-end processing platform. Each fixed node has its own fixed node identification. The dynamic node can be a portable device with an emergency illumination module. If the dynamic node is manipulated to broadcast a mayday signal, at least one of the fixed nodes senses the mayday signal. Each fixed node which senses the mayday signal sends the fixed node identification thereof and signal strength of the sensed mayday signal to the back-end processing platform. Thereby, the back-end processing platform calculates and determines a rescue location relative to the dynamic node.

Abstract: Embodiments order observed beacons based on relative signal strength to create a correspondence between beacon sets and positions. A computing device such as a mobile device provides a positioned observation including a plurality of observed beacons and a position of the mobile device during observation. The observed beacons are ordered based on quality indicators such as signal strength relative to each other. A set of the beacons are selected based on the ordering (e.g., the beacons with the strongest signal strength are selected in order). The position of the observing mobile device is associated with the beacon set to enable location inference for other devices providing observations including the same beacon set.

Abstract: A system and method for providing improved correction information to navigation receivers includes receiving, from a plurality of reference stations at known locations, a plurality of satellite navigation measurements of signals from a plurality of global navigation satellites. A state of the plurality of global navigation satellites is computed based on the received satellite navigation measurements. Baselines, each corresponding to a pair of the reference stations, are identified. For each identified baseline, computing floating and integer values for a double-differenced integer ambiguity. Double-differenced integer ambiguities that satisfy a set of predefined conditions are identified, and the computed state of the plurality of global navigation satellites is adjusted in accordance with an integer value constraint applied to each double-differenced integer ambiguity that satisfies the set of predefined conditions.

Abstract: In one of its aspects the technology concerns a method of determining a position of a wireless terminal in a radio access network using information of the travel time of radio waves between a base station and the wireless terminal, the travel time information being retrieved in a way consistent with SUPL positioning. The method comprises performing, at the wireless terminal, a time of arrival measurement for a respective downlink radio frame received from a node associated with a cell of a radio access network. The method thereafter uses the time of arrival measurement and an estimated time of downlink transmission from the node to make a determination of a distance between the wireless terminal and the node. The distance so determined can be used to generate an ellipsoid arc for describing a round trip time positioning of the wireless terminal.

Abstract: Systems and methods are described for determining position of a receiver. The positioning system comprises a transmitter network including transmitters that broadcast positioning signals. The positioning system comprises a remote receiver that acquires and tracks the positioning signals and/or satellite signals. The satellite signals are signals of a satellite-based positioning system. A first mode of the remote receiver uses terminal-based positioning in which the remote receiver computes a position using the positioning signals and/or the satellite signals. The positioning system comprises a server coupled to the remote receiver. A second operating mode of the remote receiver comprises network-based positioning in which the server computes a position of the remote receiver from the positioning signals and/or satellite signals, where the remote receiver receives and transfers to the server the positioning signals and/or satellite signals.

Abstract: A system and method for determining the location of a wireless device. A boundary for an approximate area in which the wireless device is located is determined and a plurality of satellites may be determined as a function of the boundary. Assistance data is transmitted to the device which includes information from the plurality of satellites, and the location of the wireless device may be determined from the information. In one embodiment, if the number of the plurality of satellites is greater than a predetermined threshold then the number of satellites may be reduced as a function of one or more of the elevation of each satellite above the horizon, a distance between each satellite to one or more other satellites, and an altitude of each satellite.

Abstract: A GNSS enabled mobile device receives GNSS assistance data in a determined format from a central processing station communicatively coupled to a wide area reference network (WARN). The WARN comprises a first plurality of GNSS tracking stations from which usable signals are received by the central processing station, and a second plurality of GNSS tracking stations from which unusable or no signals are received by the central processing station. The central processing station generates the GNSS assistance data using a complete set of GNSS reference feeds of the WARN. The complete set of GNSS reference feeds comprises actual GNSS reference feeds from the first plurality of GNSS tracking stations and virtual GNSS reference feeds derived for the second plurality of GNSS tracking stations from processed actual GNSS reference feeds. The generated GNSS assistance data is reformatted into a determined format and is communicated to the GNSS enabled mobile device, accordingly.

Abstract: Systems and methods are described for determining position of a receiver. The positioning system comprises a transmitter network including transmitters that broadcast positioning signals. The positioning system comprises a remote receiver that acquires and tracks the positioning signals and/or satellite signals. The satellite signals are signals of a satellite-based positioning system. A first mode of the remote receiver uses terminal-based positioning in which the remote receiver computes a position using the positioning signals and/or the satellite signals. The positioning system comprises a server coupled to the remote receiver. A second operating mode of the remote receiver comprises network-based positioning in which the server computes a position of the remote receiver from the positioning signals and/or satellite signals, where the remote receiver receives and transfers to the server the positioning signals and/or satellite signals.

Abstract: Phase shift values between signals received at a plurality of receiving antennas are determined to orient one or more receiving antennas of the plurality of receiving antennas during signal location. Subsequent signals are received utilizing the oriented receiving antennas. Candidate angle of arrival (AOA) values are computed based on the determined phase shift values during the signal location so as to adaptively orient the receiving antennas. Each of the candidate AOA values is iteratively selected one at a time to adaptively orient the receiving antennas. The receiving antennas may be adaptively oriented according to the computed receive signal power levels. The determined phase shift values may be rounded to nearest discrete phase shift values. In this regard, one candidate AOA value is selected for each of the receiving antennas based on the corresponding rounded phase shift values such that the receiving antennas may be adaptively oriented during the signal location.

Abstract: In a method of Global Navigation Satellite System (GNSS) reference station integrity monitoring, network Real Time Kinematic (RTK) information is accessed for a location associated with a GNSS reference station. At least one aspect of GNSS information local to the location of the GNSS reference station is compared with a corresponding aspect of the network RTK information. The results of the comparing are monitored for indication of occurrence of compromise to operational integrity of the GNSS reference station.

Abstract: A method for detecting hidden objects by means of electromagnetic millimeter waves is provided, in which a test object is irradiated with millimeter waves and the millimeter waves that are reflected from the test object are evaluated. The millimeter waves are focused on different depth layers of the test object during the irradiation thereof.

Abstract: A communication device is described comprising an antenna arrangement, an orientation determining device configured to determine the orientation of the antenna arrangement, and a controller configured to control the directivity of the antenna arrangement based on the determined orientation of the antenna arrangement.

Abstract: A method of calculating two position fixes, using satellite positioning. The method comprises: using an RF front-end (12), receiving satellite positioning signals; using an analogue-to-digital converter (18), sampling the received signals to generate signal samples; using a processor (20), processing a first set of the samples as they are generated, to calculate a first position fix; storing information associated with the calculation in a memory (22); storing a second set of the samples, or ranging measurements derived from the second set of samples, in the memory (22) for later processing to calculate a second position fix; and later, processing the second set of samples to calculate the second position fix, wherein the calculation of the second position fix is assisted by the information associated with the calculation of the first position fix. Also disclosed are other related methods and apparatus.