Inertial GPS navigation system
US6721657B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 4, 2002 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Jul 10, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S19/44
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A receiver that uses a single processor to control a GPS sub-system and an inertial (“INS”) sub-system and, through software integration, shares GPS and INS position and covariance information between the sub-systems. The receiver time tags the INS measurement data using a counter that is slaved to GPS time, and the receiver then uses separate INS and GPS filters to produce GPS and INS position information that is synchronized in time. The GPS/INS receiver utilizes GPS position and associated covariance information in the updating of an INS Kalman filter, which provides updated system error information that is used in propagating inertial position, velocity and attitude. Whenever the receiver is stationary after initial movement, the INS sub-system performs “zero-velocity updates,” to more accurately compensate in the Kalman filter for component measurement biases and measurement noise. Further, if the receiver loses GPS satellite signals, the receiver utilizes the inertial position, velocity and covariance information provided by the Kalman filter in the GPS filters, to speed up GPS satellite signal re-acquisition and associated ambiguity resolution operati…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.