Trimble Navigation Limited

Trimble Inc.

David G Bird

James M Janky

Harold L Longaker

Ann Ciganer

Dennis Connor

Nicholas Charles Talbot

Shawn D Weisenburger

Curt A Conquest

Frances W Miller

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 station transmission of GNSS correction data via beacon frame

This application discloses a GNSS reference apparatus having a vector error generator and a reference data server. The vector error generator generates one or more sequences of keyed intentional errors made confidential with confidential error keys, and then combines the sequences to generate a sequence of reference erroneous positions. The reference data server issues GNSS position-determination reference data based on the reference erroneous positions where the keyed intentional errors for at least one of the confidential sequences are reversible with confidential access to the corresponding confidential error key for determining a GNSS-based position.

GNSS reference for subscribed precisions

This application discloses a GNSS rover having a data receiver, a position processor and a vector error reverser. The data receiver receives GNSS position-determination reference data based on a reference erroneous position having one or more keyed intentional errors made confidential with confidential error keys. The position processor uses the GNSS position-determination reference data to determine a rover erroneous position corresponding to the reference erroneous position. The vector error reverser uses confidential access to at least one confidential error key to reverse the corresponding confidential keyed intentional error in the rover erroneous position to determine a subscribed rover position.

GNSS rover having subscribed precision

A computer apparatus for post positioning with a selected precision. The apparatus includes a GNSS post processor to post process reference GNSS carrier phases from a reference system and rover GNSS carrier phases from a rover receiver to compute a secure position for the rover receiver not available to a user. The apparatus includes a random process generator to generate a sequence of offset vectors to dither the secure position according to a computed dither level to provide the selected precision for a user-available position for the rover receiver.

GNSS post positioning with elongated dither sequence

A computer apparatus for post positioning with a selected precision. The apparatus includes a GNSS post processor to post process reference GNSS carrier phases from a reference system and rover GNSS carrier phases from a rover receiver to compute a secure position for the rover receiver not available to a user. The apparatus includes a vector offset generator to use the selected precision to compute a dither level for offset vectors to degrade an intrinsic precision of the secure position to provide a user-available position for the rover receiver at the selected precision.

GNSS post positioning with selected precision

A method and apparatus for geofencing mobile transmissions. The method includes determining a geographic location of a mobile transmitter. Then, a geographic interference contour of the mobile transmitter is determined. The mobile transmitter is operating over a specific frequency at the geographic location. A neighboring service contour is then determined. The neighboring service contour is associated with an FCC license that allows transmissions over a specific channel that includes the specific frequency. The interference geographic contour and the service contour are compared to determine if there is overlapping. Thereafter, transmissions from the mobile transmitter are controlled in order to comply with FCC regulations.

Method and apparatus for GPS geofencing of mobile transmissions

A GPS information service system for providing supplemental GPS correction and signal acquisition information to subscribers. A GPS information server broadcasts GPS aiding information encrypted with subscription keys. A remote GPS subscription unit receives the key enablers for the subscription keys in service activation (SAM) messages for the services for which they have subscribed and then uses the subscription keys to decrypt the GPS aiding information. In order to prevent unauthorized access to the information, unsymmetrical signature generation and authentication algorithms are used for generating and authenticating signatures for the SAM messages.

Remote subscription unit for GNSS information

A positioning system or synthetic phase processor or rover station for providing high integrity positions with graduated accuracies. The positioning system includes one or more real time kinematic (RTK) reference stations for receiving GPS signals at established reference positions and measuring reference phases. The positioning system or the rover station selects a synthetic offset vector and uses the synthetic offset vector for inferring synthetic reference phases to a synthetic position. The rover station uses the synthetic reference phases with actual or virtual reference positions for determining a rover position having an added positional error controlled by the synthetic offset vector. For another embodiment a positioning system or a secure rover station dithers a secure position with a synthetic offset vector for providing an unsecure rover position having the added positional error.

GPS rover station providing a high integrity position with a selected error

A positioning system or synthetic phase processor or rover station for providing high integrity positions with graduated accuracies. The positioning system includes one or more real time kinematic (RTK) reference stations for receiving GPS signals at established reference positions and measuring reference phases. The positioning system or the rover station selects a synthetic offset vector and uses the synthetic offset vector for inferring synthetic reference phases to a synthetic position. The rover station uses the synthetic reference phases with actual or virtual reference positions for determining a rover position having an added positional error controlled by the synthetic offset vector. For another embodiment a secure rover station dithers a secure position with a synthetic offset vector for providing an unsecure rover position having the added positional error.

Synthetic phase processor for controlling accuracy of high integrity GPS positions

GPS reference system providing synthetic reference phases for controlling accuracy of high integrity positions

GPS rover station having position dithering for controlling accuracy of secure positions

GPS reference system providing a synthetic offset vector for dithering a rover station position

Remote subscription unit for GPS information

A GPS information service system for providing supplemental GPS location correction and signal acquisition information to subscribers. A GPS information server broadcasts GPS information encrypted with subscription keys. Remote GPS subscription unit receive the key enablers for the subscription keys in service activation (SAM) messages for the services for which they have subscribed and then use the subscription keys to decrypt the GPS information. In order to prevent unauthorized use, the SAM messages have signatures derived from identifications of the remote GPS subscription units using an unsymmetrical signature algorithm.

Growing community of inventors

Thornton, CO, United States of America

David G Bird