A positioning apparatus, including: positioning calculation devices for positioning for a plural antenna, to acquire positioning results indicating the antennas positions and accuracy indices indicating accuracies of the positions, the antennas receiving GPS satellites signals and having a known distance between each antennas; and a determination device including: a determination unit performing first determination whether accuracies indicated by the accuracy indices of two antennas out of the plural antenna is higher than a first threshold and second determination whether a difference between a measured distance between the two antennas based on a difference between positioning results of the antennas and an actual distance therebetween is smaller than a second threshold, to thereby acquire a reliability index (RI) and a final positioning result (FPR) based on the two determinations; and an output signal generation unit for generating positioning information for controlling a human interface (HI) to notify a result based on the (FPR) and (RI).

For operating a correction service system for a satellite-based navigation system that is configured to determine a position of user devices, where the correction service system includes a plurality of reference stations having known and fixed coordinates and a plurality of receivers, a method includes operating a first group of the reference stations and the plurality of receivers, ascertaining a first correction value based on the satellite signals received by the first group of reference stations and their coordinates, ascertaining a second correction value based on the signals received by the plurality of receivers, ascertaining, based on the first and second correction values, a third correction value that is provided to the user devices.

Systems and methods for performing spoofing detection and rejection including receiving, at a Global Navigation Satellite System (GNSS) device having an antenna, a set of signals, identifying a questionable signal in the set of signals, and in accordance with a determination that the set of signals includes a subset of valid GNSS satellite signals, where the subset satisfies a minimum number of valid GNSS satellite signals and does not include the questionable signal, calculating an approximate position of the GNSS device based on the subset of valid GNSS satellite signals.

A method of positioning a device includes: receiving satellite signals corresponding to at least 5 satellites in a global navigation satellite system (GNSS); determining whether there is one of the satellite signals has a wrong bit edge from at least navigation data of the satellite signals; and in response to a determination that there is one of the satellite signals has a wrong bit edge, finding out a wrong satellite signal among the satellite signals, and using the navigation data of the other satellite signals to obtain a position of the device.

A surveying system includes a first subsystem having a GNSS base station and an optical base station. The optical base station includes an optical sensor, a laser module, and one or more motors configured to reposition the optical sensor. The GNSS base station and the optical base station are configured to be coupleable in a first predefined configuration. The system further includes a second subsystem comprising a GNSS rover communicatively coupled to the GNSS base station and an optical rover comprising a visual pattern. The GNSS rover and the optical rover are configured to be coupleable in a second predefined configuration.

An electronic device equipped with a communication device which is a GPS communication module is provided with a calculator, a specifying portion, and a display controller. The calculator calculates a position by Doppler positioning. The specifying portion specifies a time zone based on the position calculated by the calculator. The display controller causes a display device to display the time according to the time zone specified by the specifying portion.

The invention discloses an improved GNSS receiver which determines a location of the receiver by combining a first location determined either from the standard PVT of a multi-frequency receiver and/or from a positioning aid like a map matching algorithm, inertial navigation system, WiFi localization system or other, and a second location determined by integrating the velocity from the standard PVT. The combination is based on a duty cycle or a combination of the duty cycle with a weighting of the error budgets of the first position and the second location. The improved receiver is preferably based on a standard receiver with an add-on software module which receives and processes data transmitted from the standard receiver by, for example, NMEA messages. The improved receiver allows a determination of a more precise and smoother trajectory in a simple way.

There is provided a positioning system that comprises a GPS device including a GPS receiver arranged to receive GPS satellite signals from a plurality of GPS satellites and an attenuation device arranged to attenuate GPS satellite signals such that when a GPS satellite is located in a first portion of sky the GPS satellite signals received by the GPS receiver from said GPS satellite are attenuated. A storage is provided to store satellite location information for the plurality of GPS satellites over time at a location of the GPS receiver, and a controller is provided to determine location information of the GPS device based on received GPS information from the GPS device, wherein the received GPS information comprises information on signal strengths of the GPS satellite signals received by the GPS receiver. If a signal strength for a first GPS satellite is lower than a threshold signal strength at a point in time then the controller is arranged to determine that the first GPS satellite is in the first portion of the sky and determine angle information of the GPS device relative to earth's normal and/or orientation information of the GPS device in a horizontal plane using the stored satellite location information.

A method of receiving and decoding non-legacy GNSS signals and re-transmitting these in real-time as legacy GPS (L1-C/A) signals decoding into standard PVT/PNT information then re-encoding using a real-time GPS simulator as legacy GPS code signals, and outputting as a legacy GPS antenna signal. A navigational apparatus for performing the method may further include an Inertial Measurement Unit, Inertial Navigation System (IMU/INS) module and oscillator coupled to the GPS simulator for providing an inertial location signal supplementing the GNSS signal to the GPS simulator, wherein the GPS simulator encodes the RF simulated GPS signal based at least in part on the inertial location signal for a period when at least one of the GNSS signal or the PVT/PNT signal is not available.

A method for determining the position of a vehicle is disclosed. GNSS signals from a global satellite navigation system are received by a receiving device). A vehicle velocity is detected; and a check is carried out as to whether the detected vehicle velocity falls below or exceeds a threshold value. After the vehicle velocity falls below the threshold value, the position of the vehicle is determined on the basis of a first calculation method. After the vehicle velocity exceeds the threshold value, the position of the vehicle is determined on the basis of a second calculation method. Both calculation methods include filtering the GNSS signals by a fusion algorithm. The calculation methods differing by input variables of the fusion algorithm.