Rockwell Collins, Inc.

Other

Gary A McGraw

Patrick Y Hwang

Bernard A Schnaufer

Robert J Frank

Huan T Phan

Michael J Armatys

James H Doty

Vladislav Gavrilets

David A Anderson

Steven E Koenck

Dana J Jensen

Douglas A Bell

Scott J Zogg

Shih-Yih Young

Richard S Haendel

Scott J F Zogg

Guolin Peng

Brad A Walker

Gina M Reyes

Kenneth M Peterson

John R Bader

Jason H Timmerman

Patrick A Hwang

A system and for determining precision navigation solutions decorrelates GPS carrier-phase ambiguities derived from multiple-source GPS information via Least-squares AMBiguity Decorrelation Adjustment (LAMBDA) algorithms. The set of decorrelated floating-point ambiguities is used to compute protection levels and the probability of almost fix (PAF), or the probability that the partial almost-fix solution corresponding to the decorrelated ambiguities is within the region of correctly-fixed or low-error almost-fixed ambiguities. While the PAF remains below threshold and the protection levels remain below alert levels, the optimal navigation solution (floating-point, partial almost-fix, or fully fixed) is generated by fixing the decorrelated ambiguities are one at a time in the LAMBDA domain and replacing the appropriate carrier-phase ambiguities with the corresponding fixed ambiguities, reverting to the last solution if PAF reaches the threshold or if protection levels reach the alert levels.

System for determining high-integrity navigation solutions via optimal partial fixing of floating-point integer ambiguities

A system and related method for determining precision navigation solutions is disclosed. The system decorrelates GPS carrier-phase ambiguities derived from multiple-source GPS information via Least-squares AMBiguity Decorrelation Adjustment (LAMBDA) algorithms. The set of decorrelated floating-point ambiguities is used to compute protection levels and the probability of almost fix (PAF), or the probability that the partial almost-fix solution corresponding to the decorrelated ambiguities is within the region of correctly-fixed or low-error almost-fixed ambiguities. While the PAF remains below threshold and the protection levels remain below alert levels, the optimal navigation solution (floating-point, partial almost-fix, or fully fixed) is generated by fixing the decorrelated ambiguities are one at a time in the LAMBDA domain and replacing the appropriate carrier-phase ambiguities with the corresponding fixed ambiguities, reverting to the last solution if PAF reaches the threshold or if protection levels reach the alert levels.

High integrity partial almost-fix solution

A system and related methods for determining precision navigation solutions decorrelates GPS carrier-phase ambiguities derived from multiple-source GPS information via Least-squares AMBiguity Decorrelation Adjustment (LAMBDA) algorithms, and fixes a subset of the decorrelated integer ambiguities within the LAMBDA domain. To maintain high accuracy, a partial almost fix solution is generated using the subset of the decorrelated ambiguities to be fixed in the LAMBDA domain. The subset of decorrelated ambiguities is used to compute protection levels and the probability of almost fix (PAF), or that the navigation solution corresponding to the decorrelated ambiguities is within the region of correctly-fixed or low-error almost-fixed ambiguities. The partial list of fixed ambiguities is used to generate the optimal navigation solution (floating-point, partial almost-fix, or fully fixed) while maintaining protection levels within alert limits and PAF above the desired threshold.

High integrity partial almost fix solution

A system and related method for navigation and orientation determination in an indoor or GPS-denied environment mounts a static reference transceiver (SRT) at a known, fixed position within the environment, the fixed position referenced by a coordinate reference frame (CRF) of the SRT. The SRT communicates its position to mobile dismounted units within the environment, determining a range and orientation angle of each mobile unit relative to the SRT CRF based on response signals received from the mobile units. The SRT provides the determined SRT-CRF-referenced ranges and orientation angles to the mobile units, which may share orientation data with each other or relay the SRT-referenced location data to other mobile units not within line of sight of the SRT.

Indoor navigation and orientation determination system

Systems and methods for navigation of a vehicle may carry out one or more operations including, but not limited to: obtaining coordinates of a vector connecting two points in space using carrier phase measurements from global navigation system satellites (GNSS); setting the vector as an intended path of a vehicle; storing carrier phase signals from a GNSS receiver received at a first position of the vehicle; receiving carrier phase signals from a GNSS receiver at a second position of the vehicle; and determining a position of the vehicle relative to the intended path from one or more carrier phase signals received at the second position and one or more stored carrier phase signals received at the first position.

GPS carrier-phase based relative navigation

Systems and related methods for simultaneous high precision synchronization and syntonization of multiple sensors or clocks utilize a precision estimator that receives clock signals and time mark signals from both sensors (a reference sensor and a clock to be measured against the reference sensor). A precision time and frequency estimator determines a time offset, frequency offset, and phase offset of the measured sensor relative to the reference sensor. Associated systems can additionally determine the propagation delay between two remote subsystems connected by a communications channel. The communications channel may be a bidirectional duplexed or multiplexed channel allowing for mutual exchange of timing information along a single non-dedicated cable between sensors. Sensors may be synchronized to within 10 ps of each other without the need for THz clocks or fiber-optic cabling.

Picosecond clock synchronization technique for communication and navigation platform equipment

A method for providing collaborative PNT for a plurality of nodes in a distributed sensing system is disclosed. The method may include receiving carrier phase and pseudorange measurements from a first node and a second node of the plurality of nodes; providing a process model for each node, where the process model for each node is configured for modeling error characteristics associated with that node; determining an error covariance between the first node and the second node; and estimating a PNT solution for the first node and a PNT solution for the second node based on: the carrier phase and pseudorange measurements received from the first node, the carrier phase and pseudorange measurements received from the second node, the process model for the first node, the process model for the second node, and the error covariance between the first node and the second node.

Collaborative positioning, navigation and timing

The present invention is a geolocation system for providing coordinated sensing and precision geolocation of a target emitter. The system may include a Quint Networking Technology (QNT) subsystem which may be configured receiving, detecting and identifying a target emitter signal. The QNT subsystem may be further configured for extracting a carrier phase of the signal. The system may further include a Real Time Kinematic Global Positioning System (RTK GPS) subsystem for determining a position of the geolocation system relative to a position of a second geolocation system. Further, the system may be configured for communicating with the second geolocation system via a QNT communication data link for: determining a QNT time difference via signal carrier phase differencing for calculating a time difference between the geolocation systems and geolocating the target emitter based on both the relative position information of the geolocation systems and the calculated time difference between the geolocation systems.

Coordinated sensing and precision geolocation of target emitter

The present invention is directed to accurate GPS (global positioning system)-free relative navigation between an unmanned aerial vehicle (UAV) and a tanker aircraft. The UAV transmits a signal which is received by an antenna array at the tanker aircraft. Horizontal relative position of the UAV is determined by calculating range and bearing based on time and phase differences in the received signal. Vertical relative position of the UAV is determined by comparing the altitude of the UAV with the altitude of the tanker aircraft. The tanker aircraft then transmits a navigation solution based on the relative position of the UAV which is received by the UAV. The UAV may utilize the navigation solution transmitted by the tanker aircraft as a backup to a GPS determined navigation solution, in a GPS denied scenario, or in combination with an INS (inertial navigation system) determined navigation solution.

Frequency hopping data link approach to autonomous GPS denied relative navigation determination

A method and apparatus for improving differential navigation accuracy uses time transfer over a two-way communications link. The communications link transmits an overall time offset between a differential reference station and a remote user. A differential navigation position solution is modified at the remote user with the overall time offset to improve the differential navigation accuracy. A first time offset between a first communications device and a first navigation receiver at the remote user is determined. A second time offset between the first communications device at the remote user and a second communications device at the differential reference station is determined. A third time offset between the second communications device and a second navigation receiver at the differential reference station is determined. An overall time offset from the first time offset, the second time offset, and the third time offset is computed and used to improve the differential navigation accuracy.

Communications link time transfer to improve navigation system accuracy

A method of generating differentially-corrected smoothed pseudorange data in a differential global positioning system (DGPS) includes generating, at a base station, non-mode specific pseudorange and carrier phase correction data. The non-mode specific pseudorange and carrier phase correction data is then provided to a remote receiver. At the remote receiver, one of a plurality of specific smoothing modes of operation is selected for use in generating differentially-corrected smoothed pseudorange and carrier phase data. The differentially-corrected smoothed pseudorange and carrier phase data is then generated by the remote receiver using the selected one of the plurality of specific smoothing modes of operation, and as a function of the non-mode specific pseudorange and carrier phase correction data received from the base station.

Generalized divergence-free carrier smoothing and dual frequency differential GPS architecture implementing the same

A follower aircraft is guided to a lead aircraft using a datalink that determines range between the two. The lead aircraft has an antenna array and processing system for determining azimuth/elevation of the follower aircraft. The lead aircraft transmits a ranging message to the follower aircraft and stores a lead aircraft time of transmit (TOT) time. The ranging message is received at the follower aircraft and a follower aircraft time of reception (TOR) time is stored. A second ranging message is transmitted from the follower aircraft to the lead aircraft and a follower aircraft TOT time is stored. The second ranging message is received at the lead aircraft and a lead aircraft TOR is stored. A message is sent from the follower aircraft when follower aircraft TOT and TOR. The range and time offset is determined by the lead aircraft using follower aircraft TOT/TOR and stored lead aircraft TOT/TOR.

Relative navigation for precision rendezvous and station keeping using datalink signals

Communication link time transfer to improve navigation system accuracy

A new Fault Detection and Exclusion (FDE) approach for tightly integrated GPS/inertial sensors that combines a normalized solution separation for fault detection and a residual monitoring scheme for fault exclusion is described. The computation of the detection threshold, the horizontal protection level and the horizontal uncertainty level are also presented. This new FDE algorithm is designed to enable the tightly integrated GPS/inertial sensor to be used as a primary means of navigation sensor for civil aviation.

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Cedar Rapids, IA, United States of America

Gary A McGraw