Techniques for transmitting global navigation satellite system (GNSS) correction data to a rover. GNSS signals are wirelessly received by a base station from one or more GNSS satellites. GNSS correction data is generated by the base station based on the GNSS signals. A beacon frame is formed by the base station to include a frame header, a frame body, and a frame check sequence (FCS). The frame body is formed to include the GNSS correction data. The beacon frame is wirelessly transmitted by the base station for receipt by the rover. The rover wirelessly receives the beacon frame. The GNSS correction data is extracted by the rover from the beacon frame. A geospatial position of the rover is calculated based on the GNSS correction data.

Base stations of a satellite navigation system have receivers Phase biases and instrumental and atmospheric errors, are determined and transmitted to navigation devices. Precise Point Positioning includes steps of: obtaining code and phase measurements which were performed on the satellite signals by the plurality of receivers at two or more frequencies, determining separate individual values for a plurality of phase ambiguities and a plurality of the errors based on the code and phase measurements, wherein the receivers are grouped into clusters, and in each cluster a determination of a single cluster solution is performed, in which satellite errors selected from the group of satellite position errors, satellite clock errors and satellite phase biases are determined based on the phase and code measurements performed by the receivers of the respective cluster; and a multi-cluster solution is performed, in which the single cluster solutions are adjusted.

The present disclosure discloses a charging station, an intelligent robot, and a charging system. The charging station includes a control chip, a charging apparatus, and a differential positioning apparatus. The charging apparatus is electrically connected to the control chip, and the differential positioning apparatus is communicatively connected to the control chip, where the control chip is configured to receive first observation information and position information of the charging station sent by the differential positioning apparatus, and send the first observation information and the position information to an intelligent robot, and configured to control the charging apparatus to charge the intelligent robot.

A system and method for timing synchronization of global navigation satellite system (GNSS) receivers is presented. An end point equipment (EPE) of a plurality of EPEs is matched to at least one control station at a predetermined distance, which are in a user satellite network. Relative positions are determined for each matched EPE and the at least one control station based on differencing of raw measurements and a plurality of relative positions is collected of the determined relative position of each match. An absolute clock offset is estimated based on clock information of the at least one control station and the plurality of relative positions. The absolute clock offset is used to cause a time synchronization in a first EPE of a plurality of EPEs.

Methods and systems disclosed herein may include receiving signals from a transmitter in a receiver; determine a bias of the transmitter and receiver; generating expected observations, based on the bias, corresponding to the received signals; and calculate a building height based on a power level of the received signals and a power level of the expected observations.

Described are methods, systems, and devices for determining position using Differential Global Navigation Satellite (DGNSS) measurements. Techniques described herein involve taking carrier phase measurements at a reference station or other GNSS receiver at a known location, and combining the carrier phase measurements with pseudorange measurements taken at the reference station to resolve carrier phase ambiguity and to, in combination with pseudorange measurements taken at a mobile device, obtain a differentially corrected measurement that can be used to estimate a position of the mobile device. The differentially corrected measurement can be a double differential measurement based on signals from a pair of GNSS satellites.

Among other things, an equipment for use on board a first ground transportation entity has (a) a receiver for information generated by a sensor of the environment of the first ground transportation entity, (b) a processor, and (c) a memory storing instructions executable by the processor to generate and send safety message information to a second ground transportation entity based on the information generated by the sensor.

A central location system provides an end-to-end high-accuracy positioning solution that provides navigation, geo-tagging, and general positioning data to receivers. The central location system does this by providing a cloud correction service and a robust positioning engine. For example, the central location system may provide single-frequency receivers with corrections for atmospheric delays and multipath throughout different geographic regions. The central location system computes corrections by leveraging location data from dual-frequency receivers. The central location system may also increase ionospheric delay coverage of portions of a geographic region. With increased ionospheric delay coverage, receivers can compute better location estimates. The central location system may also compute refined location estimates of single-frequency receivers and/or dual-frequency receivers for receivers with limited access to signals transmitted from satellites. The central location system may do this by estimating a receiver's location with respect to the location estimates of other receivers.

A device may use Precise Point Positioning (PPP) correction information to generate Real Time Kinematic (RTK) correction information that can be sent to other devices for RTK-based positioning. In particular, according to some embodiments, the first device having access to PPP correction information may obtain the PPP correction information and generate RTK correction information by determining a virtual RTK base station location and generating, based on the PPP correction information, a virtual Multi-Constellation Multi-Frequency (MCMF) measurement corresponding to the determined virtual RTK base station location. This virtual MCMF measurement (and/or data derived therefrom) can then be sent to other devices as RTK correction information.

Methods, apparatus, systems and articles of manufacture are disclosed to manage correction requests in a positioning system. Example apparatus disclosed herein includes accuracy determination circuitry to determine accuracy of a current position based on location data. The example apparatus includes correction request circuitry to request location correction data from a reference location when the accuracy does not satisfy a threshold. The example apparatus includes correction determination circuitry to adjust the location data with location correction data.