US6091359A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Portable dead reckoning system for extending GPS coverage
Assignee: Aumovio Systems Inc
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Filing: 1997-07-14
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Granted: 2000-07-18
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Expires: 2017-07-14
Abstract
Abstract This invention extends GPS coverage in an automotive environment without requiring direct interfaces to the vehicle's sensors in a unique and cost effective way. Since it removes all required vehicle interfaces (except power), it produces a virtually portable navigation system with no installation requirements beyond that of the GPS receiver itself. It also removes the necessary "customization" of the navigation system to each particular vehicle. Fundamentally, the position of a vehicle is obtained by GPS receiver data augmented with a low cost gyro whereby the gyro accurately tracks the heading changes of the vehicle (in the absence of sufficient GPS information), and the GPS receiver includes an innovative algorithm for deriving speed information from Doppler measurements from just one or two GPS satellites.
Inventors
- 👤 George Jeffrey Geier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:42
CPC Classifications
G; G01; G01C; G01C21/00; G01C21/26; G01C21/28; G01C21/20; G01S; G01S19/00; G01S19/38; G01S19/39; G01S19/42; G01S19/48; G01S19/49
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
123 words
A method for extending Global Positioning System (GPS) coverage of a movable vehicle in which a navigation system is installed, said navigation system comprised of a GPS receiver and a gyro, said method comprising the steps of: determining whether a sufficient number of GPS satellites are tracked to obtain a reliable position of said movable vehicle based upon GPS data; receiving heading information from said gyro; determining vehicle acceleration information of said movable vehicle from at least one GPS satellite; combining heading information from said gyro with said vehicle acceleration information; using said combined heading and vehicle acceleration information to obtain a position estimate of said movable vehicle; and determining whether an uncertainty level of said position estimate has exceeded a predetermined value.
Claim 2
Independent Claim
123 words
A method for extending Global Positioning System (GPS) coverage of a movable vehicle in which a navigation system is installed, said navigation system comprised of a GPS receiver and a gyro, said method comprising the steps of: determining whether a sufficient number of GPS satellites are tracked to obtain a reliable position of said movable vehicle based upon GPS data; receiving heading information from said gyro; determining vehicle acceleration information of said movable vehicle from at least one GPS satellite; combining heading information from said gyro with said vehicle acceleration information; using said combined heading and vehicle acceleration information to obtain a position estimate of said movable vehicle; and determining whether an uncertainty level of said position estimate has exceeded a predetermined value.
Claim 3
Dependent Claim
36 words
The method of claim 1 further including the steps of: receiving GPS velocity data when data from said sufficient number of GPS satellites are available; and using said received GPS velocity data to calibrate said gyro.
Claim 4
Dependent Claim
34 words
The method of claim 1 further including the steps of: estimating an error associated with said position estimate of said movable vehicle; and disregarding said position estimate when said error exceeds a predetermined value.
Claim 5
Dependent Claim
17 words
The method of claim 1 wherein said vehicle acceleration information is derived from two GPS Doppler measurements.
Claim 6
Dependent Claim
25 words
The method of claim 1 wherein said vehicle acceleration information is derived from a single GPS Doppler measurements augmented by a user clock error propagation.
Claim 7
Dependent Claim
23 words
The method of claim 1 wherein said vehicle acceleration information is determined through maximum acceleration constraints based upon said vehicle's maximum lateral acceleration.
Claim 8
Dependent Claim
15 words
The method of claim 1 wherein said vehicle acceleration information is assumed to be zero.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-07-18 | 2004-01-17 | 2004-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-07-18 | 2008-01-17 | 2008-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-07-18 | 2012-01-17 | 2012-07-18 | $7700.00 | Window Closed / Lapsed |