Abstract:
A reception unit receives global positioning system signals transmitted by a plurality of satellites to obtain satellite information. A determination unit determines whether or not a state in which the reception unit receives the global positioning system signals is a predetermined reception state. A positional calculation unit calculates a current position based on ephemeris information and almanac information when the reception state is the predetermined reception state, the ephemeris information including at least six orbital elements and being obtained from satellite information of first and second satellites among satellite information of three satellites, and the almanac information including at least six orbital elements on a general orbit of a third satellite of the three satellites.
Abstract:
Methods, systems and computer program products for determining a location of a device based on location information are described. In some implementations, location assist information may be requested so as to determine a location of sufficient quality to satisfy a requesting application. Upon receiving the location assist information, empherides from one or more visible sources may be requested. The location assist information may be used to determine the location of the device until the device has received and decoded the empherides.
Abstract:
A method of predicting a location of a satellite is provided wherein the GPS device, based on previously received information about the position of a satellite, such as an ephemeris, generates a correction acceleration of the satellite that can be used to predict the position of the satellite outside of the time frame in which the previously received information was valid. The calculations can be performed entirely on the GPS device, and do not require assistance from a server. However, if assistance from a server is available to the GPS device, the assistance information can be used to increase the accuracy of the predicted position.
Abstract:
A system for positioning an object provided with a receiver, which includes a set of pseudolites transmitting positioning signals and distributed in a constrained area, assistance means capable of communicating with said receiver and calculating a position of the object, and a server capable of dynamically configuring the set of pseudolites, the pseudolites each further having a spreading code corresponding to that of a satellite belonging to a satellite constellation in a satellite navigation system, the dynamic configuration of the pseudolites by the server is such that the spreading codes of said pseudolites correspond to spreading codes of satellites of the satellite constellation not visible to the receiver of the object, wherein the assistance means is configured to communicate to said receiver a list of spreading codes meant to be those of the satellites visible to said receiver but actually corresponds to the spreading codes of the set of pseudolites so as to deceive the receiver that can acquire the positioning signals transmitted by the pseudolites and communicate with the assistance means so that the assistance means calculates the position of the object.
Abstract:
A protocol independent interface for processing, within a mobile device, protocol aiding data received at a call processor with a Global Positioning System (“GPS”) interface, where the protocol aiding data is produced according to a Geolocation Server Station protocol is disclosed. The protocol independent interface may include a means for receiving, at the GPS interface, the protocol aiding data received at the call processor, means for converting the received protocol aiding data to interface data that is transparent to the Geolocation Server Station protocol, and means for passing the interface data to a GPS module.
Abstract:
Method and apparatus for locating position of a remote receiver is described. In one example, long term satellite tracking data is obtained at a remote receiver. Satellite positioning system (SPS) satellites are detected. Pseudoranges are determined from the remote receiver to the detected SPS satellites. Position of the remote receiver is computed using the pseudoranges and the long term satellite tracking data. SPS satellites may be detected using at least one of acquisition assistance data computed using a previously computed position and a blind search. Use of long term satellite tracking data obviates the need for the remote receiver to decode ephemeris from the satellites. In addition, position of the remote receiver is computed without obtaining an initial position estimate from a server or network.
Abstract:
Methods and apparatus are described for processing a set of GNSS signal data derived from code observations and carrier-phase observations at multiple receivers of GNSS signals of multiple satellites over multiple epochs, the GNSS signals having at least two carrier frequencies, comprising: forming an MW (Melbourne-Wübbena) combination per receiver-satellite pairing at each epoch to obtain a MW data set per epoch, and estimating from the MW data set per epoch an MW bias per satellite which may vary from epoch to epoch, and a set of WL (widelane) ambiguities, each WL ambiguity corresponding to one of a receiver-satellite link and a satellite-receiver-satellite link, wherein the MW bias per satellite is modeled as one of (i) a single estimation parameter and (ii) an estimated offset plus harmonic variations with estimated amplitudes.
Abstract:
A device can access scaled values and scaling factors, which are used to convert the scaled values into coefficients and residuals. The coefficients and residuals can in turn be used with time-dependent functions to reconstruct predicted ephemeris data, including clock correction data, for satellite navigation system satellites. Ephemeris data that is broadcast from any of the satellites can be used to update the calculated ephemeris data.
Abstract:
A method and apparatus for distributing satellite navigation data is described. In one example, satellite signals are processed at each of a plurality of reference stations to receive a respective plurality of satellite navigation data streams. Packets are formed in response to said plurality of satellite navigation data streams to generate a plurality of packetized satellite navigation data streams. The packetized satellite navigation data streams are sent to a processing system. The processing system removes duplicate packets within said plurality of packetized satellite navigation data streams to generate a combined packet stream. The combined packet stream is then sent into a communication network.
Abstract:
A handheld electronic device, such as a GPS-enabled wireless communications device with an embedded camera, a GPS-enabled camera-phone or a GPS-enabled digital camera, determines whether ephemeris data needs to be obtained for geotagging digital photos taken with the device. By monitoring user activity with respect to the camera, such as activation of the camera, the device can begin pre-acquisition of a GPS position fix by obtaining needed ephemeris data before the photograph is actually taken. This GPS pre-acquisition improves the likelihood that a position fix (GPS lock) is achieved by the time the photo is taken (to enable immediate geotagging). Alternatively, the photo can be geotagged retroactively by appending the current location to the metadata tag associated with the digital photo. An optional acquisition status indicator can be displayed on a user interface of the device to indicate that a position fix is being obtained.