Described are methods, systems, and devices for correcting ionospheric error. In some aspects, a mobile device equipped with a Global Navigation Satellite System (GNSS) receiver is configured to determine a positioning measurement of a GNSS signal. The mobile device is further configured to receive augmentation data from an augmentation system. When augmentation data for a current measurement period is unavailable, the mobile device can obtain augmentation data associated with Total Electron Content (TEC) values (e.g., vertical TEC values) during one or more prior measurement periods. Based on the augmentation data associated with TEC values during one or more prior measurement periods and a pierce point of the received GNSS signal, an ionospheric error in the positioning measurement of the GNSS signal can be determined and corrected.

Several examples of a navigation disruption device and methods of using the same are described herein that use real-time, low-cost computation to generate conflicting/competing signals to actual Global Navigation Satellite System (GNSS) signals. For example, the novel, hand-held navigation disruption devices described herein (1) generate signals from a simulated satellite constellation, wherein the signals from the simulated satellite constellation conflict/compete with signals from one or more actual satellite constellations, and (2) transmit the signals from the simulated satellite constellation(s) towards an unmanned vehicle. The signals from the simulated satellite constellation(s) cause the unmanned vehicle to compute an incorrect position, which in turn disrupts its ability to navigate and operate effectively.

A system and method of identifying and responding to a GPS denial of service includes: configuring a mode S transponder for transmitting a GPS time-of-day message as a downlink format message using a BDS register, and configuring an aircraft surveillance system for receiving one or more GPS time-of-day messages transmitted as a downlink format message. The surveillance system compares the received time-of-day message(s) from the aircraft to a comparison time of day, and validates reception of authentic GPS signals by the aircraft when the received time-of-day message is within a threshold amount of the comparison time of day. The comparison time of day may be the GPS time of day of one of a plurality of aircraft in the surveillance volume or may be the GPS time of day determined by the aircraft surveillance system. An indicator on the transponder indicates counterfeit GPS signals, permitting mitigation od induced navigation error.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first user equipment (UE) may transmit, to a second UE, a system information block (SIB) that includes first timing information. The UE may transmit, to the second UE, second timing information associated with an update to the first timing information. Numerous other aspects are described.

An apparatus and a method for providing a global localization output are provided. When the apparatus receives navigation signals, the apparatus processes the signals to determine, based on a fixed earth-centered, earth-fixed (ECEF) reference pose of a reference point in an ECEF coordinate, a new ECEF pose, and to convert the fixed ECEF reference pose to an east-north-up (ENU) reference pose in an ENU coordinate. When the apparatus determines that a jump occurs in the new ECEF pose based on a pose change between the new ECEF pose and a previous ECEF pose, the apparatus calculates a reference shift of the ENU reference pose based on the pose change to absorb the jump in the ENU coordinate, and updates the ENU reference pose based on the reference shift. Thus, a new ENU local pose may be obtained using the ENU reference pose.

A navigation processing system includes at least one processor configured to execute operational instructions that cause the at least one processor to perform operations that include generating navigation data. A data stream is generated based on the navigation data and a data channel spreading sequence. A pilot stream is generated based on a pilot channel spreading sequence. A navigation signal is generated based on applying a bandwidth-efficient modulation scheme to the data stream and the pilot stream. The navigation is signal is broadcast via a navigation signal transmitter for receipt by at least one client device.

A method for maintaining timing accuracy in a mobile device includes: obtaining a range estimate using a signal received from a timing information source via a communication unit of the mobile device; obtaining position and velocity estimate information for the mobile device from a source of position and velocity information separate from the timing information source, the position and velocity estimate information being obtained from at least one sensor of the mobile device, or via a communication unit of the mobile device using a Vehicle-to-Everything wireless communication protocol, or a combination thereof; determining estimated clock parameters based on the position and velocity estimate information and the range estimate; and adjusting a clock of the mobile device based on the estimated clock parameters in response to a position-and-velocity-assisted timing uncertainty corresponding to the estimated clock parameters being below a timing uncertainty threshold.

Provided is a method and apparatus for selecting an airborne position reference node. A weight center coordinate of the repeaters is calculated by using position coordinates of repeaters, a plane having a vector connecting the weight center coordinate and a position coordinate of a user as a normal vector is determined, and the position coordinates of the repeaters are orthographically projected onto the plane. A certain number of repeaters located farthest from the weight center coordinate of the repeaters are selected to be airborne position reference nodes, on the basis of the orthographically projected coordinates of the repeaters and the weight center coordinate.

Outdoor positioning for a plurality of mobile terminals is performed using an indoor positioning system including a plurality of base stations, by (a) installing the plurality of base stations on respective outdoor locations in an outdoor area, where the base stations are configured to use a predetermined communications link for indoor positioning at indoor locations, (b) performing independent precise positioning at each of the plurality of base stations using a plurality of GNSS signals, thereby determining a precise position of the outdoor location of each base station without surveying or measuring the installed location thereof, and (c) performing outdoor positioning of the plurality of mobile terminals in the outdoor area using the determined precise position of each of the plurality of base stations in a same manner as the indoor positioning, by receiving, at the plurality of base stations, signals from the respective mobile terminals via the predetermined communications link.

Outdoor positioning for a plurality of mobile terminals is performed using an indoor positioning system including a plurality of base stations, by (a) installing the plurality of base stations on respective outdoor locations in an outdoor area, where the base stations are configured to use a predetermined communications link for indoor positioning at indoor locations, (b) performing independent precise positioning at each of the plurality of base stations using a plurality of GNSS signals, thereby determining a precise position of the outdoor location of each base station without surveying or measuring the installed location thereof, and (c) performing outdoor positioning of the plurality of mobile terminals in the outdoor area using the determined precise position of each of the plurality of base stations in a same manner as the indoor positioning, by receiving, at the plurality of base stations, signals from the respective mobile terminals via the predetermined communications link.