Patent US3630079A successfully refreshed from Google Patents.
US3630079A
Expired / Lapsed
US
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Navigation method and apparatus utilizing multiple sensors
Assignee: Texas Instruments Inc
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Filing: 1969-03-27
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Granted: 1971-12-28
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Expires: 1989-03-27
Abstract
Abstract The disclosure is directed to a navigation system for a vessel including a radio navigation system for generating signals representative of the absolute position of the vessel. A second independent system utilizing radio signals from an orbiting satellite also generates signals representative of the absolute position of the vessel. Other sensors including an acoustic doppler, navigation unit, a water speed indicator and a gyrocompass generate signals which can be combined to produce a signal representative of the position of the vessel relative to a reference location. A computer combines each of the signals according to certain weighting functions in order to generate a resultant output signal which to a minimum mean squared error sense provides extremely accurate and reliable position information for the vessel.
Inventors
- 👤 John Mark Hughes
- 👤 David Raynold Reinhartsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:35
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
109 words
A navigational system for a vehicle comprising: at least one sensing system for generating a signal indicative of the absolute position of the vehicle, at least one other sensing system for generating a signal representative of the position of the vehicle relative to a reference location, and means for applying optimum weighting coefficients to said signals to vary the amplitude thereof, said weighting coefficients being determined in accordance with measurement error statistics of the respective systems and statistics of position determination to generate a resultant navigational signal having a minimum mean squared error thereby locating the absolute position of said vessel within a significantly reduced circle of error probability.
Claim 2
Dependent Claim
109 words
A navigational system for a vehicle comprising: at least one sensing system for generating a signal indicative of the absolute position of the vehicle, at least one other sensing system for generating a signal representative of the position of the vehicle relative to a reference location, and means for applying optimum weighting coefficients to said signals to vary the amplitude thereof, said weighting coefficients being determined in accordance with measurement error statistics of the respective systems and statistics of position determination to generate a resultant navigational signal having a minimum mean squared error thereby locating the absolute position of said vessel within a significantly reduced circle of error probability.
Claim 3
Dependent Claim
22 words
The system of claim 1 wherein said one sensing system comprises receivers for intermittently receiving radio signals transmitted from an orbiting satellite.
Claim 4
Dependent Claim
24 words
The system of claim 2 and further comprising: radio navigation means for generating navigation data in response radio signals received from fixed transmitting stations.
Claim 5
Dependent Claim
34 words
The system of claim 3 and further comprising: gyrocompass means for generating substantially real time representations of the vessel position relative to a location determined by said radio signals transmitted from the orbiting satellite.
Claim 6
Dependent Claim
42 words
The system of claim 4 and further comprising: means for comparing the output signals from said radio navigation means and said gyrocompass means to generate an error signal, and means for correcting the resultant navigational signal in response to said error signal.
Claim 7
Dependent Claim
23 words
The system of claim 3 and further comprising: means for correcting the output of said radio navigation means according to predetermined diUrnal variations.
Claim 8
Dependent Claim
95 words
A navigation system comprising: means for generating position signals in response to reception of radio signals transmitted from known locations, said means including a satellite navigation system and a VLF radio navigation system, sensor means for generating speed and heading signals, means for combining said position signals and said speed and heading signals to produce a resultant navigational signal having a minimum mean squared error, means for comparing the position signals with said speed and heading signals to generate an error signal, and means responsive to said error signal for correcting said resultant navigation signal.
Claim 9
Dependent Claim
95 words
A navigation system comprising: means for generating position signals in response to reception of radio signals transmitted from known locations, said means including a satellite navigation system and a VLF radio navigation system, sensor means for generating speed and heading signals, means for combining said position signals and said speed and heading signals to produce a resultant navigational signal having a minimum mean squared error, means for comparing the position signals with said speed and heading signals to generate an error signal, and means responsive to said error signal for correcting said resultant navigation signal.
Claim 10
Dependent Claim
28 words
The navigation system of claim 7 wherein said means for generating speed and heading includes: means for generating indications of water speed, gyrocompass means, and doppler radar means.
Claim 11
Dependent Claim
30 words
The navigation system of claim 7 wherein the means for comparing signals determines varying weighting coefficients for each signal according to the sensed relative accuracy of said resultant navigation signal.
Claim 12
Dependent Claim
24 words
The navigation system of claim 7 wherein said means for combining the position signals with the speed and heading signals comprises a digital computer.
Claim 13
Dependent Claim
60 words
The navigation system of claim 7 wherein said position and speed and heading signals are varied by weighting coefficients having magnitudes determined by a minimum means square error function, said function being dependent upon the relative accuracy of said means for generating position signals, said means for generating speed and heading signals, and the time interval between satellite radio signals.
Claim 14
Dependent Claim
65 words
The navigation system of claim 7 and further comprising: first digital computer means responsive to the reception of radio signals from an orbiting satellite to generate digital signals representative of the absolute position of the vessel, and second digital computer means responsive to the output of said first digital computer means, said radio navigation means and said sensor means for generating said resultant navigation output.
Claim 15
Independent Claim
122 words
A method of navigation comprising: generating a first signal representative of the absolute position of a vehicle, generating a second signal representative of the position of the vehicle relative to a fixed known location, varying the magnitude of said first and second signals by applying weighting coefficients determined in accordance with preselected criteria including measurement error statistics associated with said first and second signals and statistics of position determination, and generating a minimum mean squared error resultant output navigation signal in response to the weighted first and second signals, said output navigational signal defining the absolute position of said vehicle in terms of latitude and longitude with a greater accuracy and reliability than either one of said first or second signals independently.
Claim 16
Independent Claim
122 words
A method of navigation comprising: generating a first signal representative of the absolute position of a vehicle, generating a second signal representative of the position of the vehicle relative to a fixed known location, varying the magnitude of said first and second signals by applying weighting coefficients determined in accordance with preselected criteria including measurement error statistics associated with said first and second signals and statistics of position determination, and generating a minimum mean squared error resultant output navigation signal in response to the weighted first and second signals, said output navigational signal defining the absolute position of said vehicle in terms of latitude and longitude with a greater accuracy and reliability than either one of said first or second signals independently.
Claim 17
Dependent Claim
46 words
The method of claim 13 wherein said preselected criteria is further characterized as comprising: a fixed relationship between the accuracy of said first and second signals, the speed of the vehicle, and the time intervals between new position fixes provided by said first and second signals.
Claim 18
Dependent Claim
21 words
The method of claim 14 wherein said first signal is generated in response to radio signals received from fixed remote locations.
Claim 19
Dependent Claim
21 words
The method of claim 14 wherein said second signal is generated in response to indications of the vehicle speed and heading.
Claim 20
Dependent Claim
31 words
The method of claim 14 and further comprising: sensing said first and second signals, and decreasing the weighting of said signals in case of inaccuracies or inconsistencies induced by external factors.
Claim 21
Dependent Claim
20 words
The method of claim 13 wherein said first signal is generated in response to signals received from an orbiting satellite.
Claim 22
Dependent Claim
137 words
An all weather navigational system for accurately plotting the absolute location of a vessEl comprising: a first sensing system for periodically receiving radio signals from an orbiting satellite to thereby accurately locate the absolute position of said vessel at a given point in time, a second sensing system including an EM log, gyrocompass, and VLF receivers to provide continuous navigation information during the interval between satellite signals, and means for combining signals from said first and second systems to provide a resultant minimum means squared error navigational signal that accurately plots a trajectory of the absolute position of the vessel between satellite signals, said combination of signals being effected by the determination of optimum weighting coefficients to be applied to each sensor output considering measurement error statistics of the respective sensors and statistics of the position determination.
Claim 23
Dependent Claim
137 words
An all weather navigational system for accurately plotting the absolute location of a vessEl comprising: a first sensing system for periodically receiving radio signals from an orbiting satellite to thereby accurately locate the absolute position of said vessel at a given point in time, a second sensing system including an EM log, gyrocompass, and VLF receivers to provide continuous navigation information during the interval between satellite signals, and means for combining signals from said first and second systems to provide a resultant minimum means squared error navigational signal that accurately plots a trajectory of the absolute position of the vessel between satellite signals, said combination of signals being effected by the determination of optimum weighting coefficients to be applied to each sensor output considering measurement error statistics of the respective sensors and statistics of the position determination.
Claim 24
Dependent Claim
79 words
A navigational system as set forth in claim 19 wherein said means for combining the signals from said first and second sensing systems include: a first digital computer responsive to the reception of radio signals from said orbiting satellite; a second digital computer responsive to the output of said first digital computer and said second sensing system, and formatting circuitry for translating the outputs of said first and second sensing systems to digital signals for inputs to said computers.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |