Abstract: Various methods, apparatuses and/or articles of manufacture are provided which may be implemented to perform and/or otherwise support collaborative navigation between a plurality of mobile devices. In one example, a first mobile device, in response to a determination that at least a second mobile device is located within a threshold distance of the first mobile device, may obtain a navigation parameter indicative of an initial position and/or movement of the second mobile device which was determined based, at least in part, on a measurement from a sensor at the second mobile device. The first mobile device then affect a determined position and/or movement of the first mobile device based, at least in part, on the navigation parameter.

Abstract: An apparatus and method is provided for indoor/outdoor transition detection of devices to improve selection of the navigation algorithms. To determine whether an outdoor-to-indoor transition has occurred, a mobile device can determine whether a difference between an indoor position determined using indoor position information and outdoor position determined using outdoor position information is less than a threshold and can conclude that the mobile device transitioned from outdoor to indoor of the structure, if the difference is less than the threshold. Also, to determine whether an indoor-to-outdoor transition has occurred, the mobile device can determine whether an indoor position survey area exists, determine whether an outdoor position determined based on outdoor position information is outside of the survey area, and determine whether a signal strength associated with the outdoor position location information is greater than a threshold.

Abstract: A receiver receiving global positioning data from one or more satellites above the Earth's surface detects a change in at least one parameter associated with the receiver and determines if the change is to be treated as erroneous. As a result of determining if the change in the at least one parameter is to be treated as erroneous, a further action may be performed. Determining if the change is to be treated as erroneous may include, for example, detecting changes in more than one parameter and determining if the changes are coincident. Detecting the change may also enable the receiver to predict the presence and magnitude of multipath components of signals, predict changes in an environment local to the receiver, predict large errors in position estimates determined by the receiver and modify an acquisition and tracking strategy used by the receiver.

Abstract: A method for locating a transmitter using a receiver which include, but are not limited to the steps of transmitting a plurality of distinctive and orthogonally polarized signals from a transmitter; receiving the transmitted signals at a pair of separated antennas; demodulating the distinctive orthogonal signals received at each of the pair of separated antennas; and determining a direction to the transmitter from the signals received at the pair of antennas.

Abstract: A low noise amplifier (LNA) assembly comprising a filter circuit for receiving signals from a Mobile Satellite Service (MSS) band and a Radio Navigation Satellite Service (RNSS) band; and an alternative filter circuit configured to filter out a jammer signal.

Abstract: An apparatus comprising a plurality of radiating elements and a plurality of surface wave feeds. Each radiating element in the plurality of radiating elements comprises a number of surface wave channels in which each of the number of surface wave channels is configured to constrain a path of a surface wave. A surface wave feed in the plurality of surface wave feeds is configured to couple a surface wave channel in the number of surface wave channels of a radiating element in the plurality of radiating elements to a transmission line configured to carry a radio frequency signal.

Abstract: A method for determining the integrity risk at an alert limit of a position solution determined with a satellite navigation system involves calculating a first integrity risk at the alert limit assuming that one satellite j of the satellites is faulty. A first position solution is determined with the signals from all of the satellites and a second position solution is determined with the signals from all of the satellites except for the signal received from the satellite j. A difference between the first and the second position solution is identified and subtracted from the alert limit to create a reduced alert limit. A second integrity risk at the reduced alert limit is calculated with the signals received from all satellites except the signal received from the satellite j. The integrity risk at the alert limit is determined using the minimum of the first and second integrity risks.

Abstract: System and method for determining the roll rate and roll angle of a spinning platform. The IQ amplitude and/or phase characteristics of GPS signals received at a single receiver antenna are measured using the signals output directly by a correlator that is driven at the satellite tracking frequency used for forming the navigation solution. The roll rate and roll angle are determined in real time by a Roll filter, which is preferably an Extended Kalman Filter (EKF) employing probabilistic data association, whose inputs include the measured IQ characteristics and the navigation solution. Data from non-GPS measurement sources is optionally provided to update the navigation and/or roll solution.

Abstract: A method of detecting an unknown signal and estimating a source location of the unknown signal using aircraft based on an automatic dependent surveillance-broadcast (ADS-B) system is provided. The method includes a first step (S100) for obtaining from a plurality of airborne aircrafts provided with a network system, aircraft signals transmitted to an air traffic control (ATC) and a second step (S200) for detecting, by the ATC, a presence of an unknown signal in the aircraft signals based on one of a time difference of arrival (TDOA) method, a time of arrival (TOA) method, and an angle of arrival (AOA) method. The method further includes a third step (S300) for estimating the source location of the unknown signal and a fourth step (S400) for transmitting unknown signal generation information associated with the unknown signal and the source location of the unknown signal to neighboring aircraft and the ATC.

Abstract: System and apparatus embodiments are provided for beam-steering. In an embodiment, an apparatus includes a first hybrid splitter/combiner connected to a 0-th phase-mode feed of an array of antenna elements, a second hybrid splitter/combiner, a first pair of variable phase shifters connecting the first hybrid splitter/combiner to the second hybrid splitter/combiner, wherein the first pair of variable phase shifters control a steering direction of a main output beam radial with respect to an array axis by adjustments of respective phases of the variable phase shifters, and wherein the array axis is perpendicular to a plane of the array, and a third variable phase shifter connecting a 1-st phase-mode feed of an array of elements to an input of the first hybrid splitter/combiner, wherein the third variable phase shifter is configured to independently control a direction of the main output beam in a direction circumferential with respect to the array axis.

Abstract: GPS receivers obtain GPS navigation data from acquired GPS satellites and determine a position of the GPS receiver. However, the GPS receivers may not always be in view of the GPS satellites or may receive GPS signals that are too weak to decode. Moreover, assisted GPS techniques rely on the ability of the GPS receivers to connect to auxiliary channels to receive navigation data, which might not always be possible. Functionality for powerline-aided GPS can be implemented to provide the navigation data, with varying levels of accuracy via a powerline network, when the GPS satellites are not in view of the GPS receiver. Moreover, the GPS receiver can use the navigation data to determine the position of the GPS receiver and/or to synchronize a local clock in the GPS receiver. Receiving the navigation data can ensure that the GPS receiver has a fast time to first fix.

Abstract: The invention relates to a method for calibrating an antenna of a receiver of signals (s1, . . . , sN) originating from a plurality of sources, said receiver comprising a plurality of sensors (c1, . . . , cM), characterized in that it comprises the following steps: measurement of a phase shift (dm,n measure) for each of the sensors (c1, . . . , cM) on each of the signals (s1, . . . , sN), determination of at least one attitude value of the antenna, said attitude being defined by a set of coordinates, calculation, for each of the sensors on each of the signals, of a theoretical phase shift (dm,n theoretical) as a function of the attitude of the antenna, from the directions of arrival of the signals, calculation of a bias (?1 sensor m) for each of the sensors from the measured phase shifts (dm,n measure) and from the theoretical phase shifts (dm,n theoretical) of the sensor.

Abstract: Provided is an apparatus and method for generating a satellite navigation signal, the method including: extracting, navigation data that is a parameter required to generate a navigation message; verifying visible satellites at a current position of a receiver based on a position of the receiver and positions of satellites calculated based on navigation data; calculating a pseudo distance from each visible satellite and a Doppler of each visible satellite; calculating, as a Doppler period, a duration of time corresponding to a Doppler displacement capable of being processed at the receiver; generating a navigation message frame to generate a satellite navigation signal, based on navigation data and a TOW; and generating a satellite navigation signal of a digitized IF for each visible satellite based on the navigation message frame, the pseudo distance for each visible satellite, and the Doppler for each visible satellite during the Doppler period.

Abstract: In one implementation, a minimum metric function with an output representing a metric of a satisfaction of transmission requirements for a satellite communications system configured to produce at least two beams may be generated. The minimum metric function may be a function of beam weight parameters including a first and second set of beam weight parameters representing output signals of high power amplifiers used to form a first and second beam, respectively. An output value of the minimum metric function may be calculated using initial values for the beam weight parameters. A direction to modify the values of the beam weight parameters may be determined based on the calculated output value. Updated values of the beam weight parameters may be determined based on maximizing the output value of the minimum metric function by moving the values of the beam weight parameters in the determined direction.

Abstract: Methods of testing GNSS-based positioning systems in obstructed environments may include specifying a required accuracy threshold for use in determining a reference trajectory. One or more difficult areas of relatively poor or missing GNSS availability may be located within the obstructed environment. Positioning information may be established for first reference points outside the difficult areas. Subsequently, by surveying with respect to the first reference points, positioning information may be established for second reference points within the difficult areas. The first and second reference points may then be used to determine a true path associated with the reference trajectory.

Abstract: An ultra wideband (UWB) or short-pulse RF system is disclosed that can be used to precisely locate or track objects (such as personnel, equipment, assets, etc.) in real-time in an arbitrarily large, physically connected or disconnected, multipath and/or noisy environment. A system implementation includes multiple zones or groups of receivers that receives RF signals transmitted by one or more timing reference tags and one or more objects having associated object tags. Each zone or group may share a common receiver. By combining a multiple reference tag system with a virtual group of receivers, i.e., a zoning technique or system, a cost-effective system can be provided that offers scalability and flexibility to monitor a significantly expanded coverage area.

Abstract: A mobile communications device uses a method for determining position that involves a positioning filter, such as a Kalman filter, which is initialized with measurements from reference stations such as satellite vehicles and/or base stations which may be acquired during different epochs. Accordingly, the positioning filter may be used for position estimation without the need to first acquire at least three different signals during the same measurement epoch.

Abstract: Various methods, apparatuses, and systems for providing a delayed geotag using GPS devices are described. The GPS device includes a wireless receiver configured to receive satellite state data and satellite range measurements from a plurality of satellites, a communications interface in communication with a media device, and a position engine configured to calculate a geotag. The GPS device can be configured to receive satellite range measurements from one or more satellites at a first point in time when the satellite state data for a minimum number of the satellites is unavailable, and to calculate the satellite state data at that time using satellite state data received at a second, later point in time. The satellite state information at the first point in time is calculated using an algorithm to extrapolate the satellite state data back to the first point in time when the satellite range measurements were made.

Abstract: GNSS receivers and methods of determining a current receiver state of a GNSS receiver are provided. The method includes receiving positioning signals from a plurality of satellites; generating a plurality of correlation grids from the received positioning signals, where each correlation grid is associated with a respective one of the plurality of satellites; estimating a probability distribution of the current receiver state from the plurality of correlation grids; and determining a maximum likelihood estimate of the current receiver state from the estimated probability distribution.

Abstract: A system and method for determining the location of a mobile device in a communications network having one or more proximity sensors. A request to locate the mobile device may be received and at least one of the proximity sensors tasked to receive a signal transmission from the mobile device. One or more signal characteristics of the signal transmission from the mobile device may be measured by each tasked proximity sensor, and a location of the mobile device determined as a function of the measured characteristics. This may be accomplished by associating a fixed location with each tasked proximity sensor, and then determining the location of the mobile device as a function of one of the associated fixed locations.