CA2175945A1 - Integrated GPS/Inertial Navigation Apparatus Providing Improved Heading Estimates - Google Patents

Integrated GPS/Inertial Navigation Apparatus Providing Improved Heading Estimates

Info

Publication number
CA2175945A1
CA2175945A1 CA2175945A CA2175945A CA2175945A1 CA 2175945 A1 CA2175945 A1 CA 2175945A1 CA 2175945 A CA2175945 A CA 2175945A CA 2175945 A CA2175945 A CA 2175945A CA 2175945 A1 CA2175945 A1 CA 2175945A1
Authority
CA
Canada
Prior art keywords
phase
inertial navigation
time period
navigation system
component signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA2175945A
Other languages
French (fr)
Other versions
CA2175945C (en
Inventor
Robert E. Ebner
Ronald A. Brown
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Northrop Grumman Guidance and Electronics Co Inc
Original Assignee
Litton Systems Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Litton Systems Inc filed Critical Litton Systems Inc
Publication of CA2175945A1 publication Critical patent/CA2175945A1/en
Application granted granted Critical
Publication of CA2175945C publication Critical patent/CA2175945C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
    • G01C21/10—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration
    • G01C21/12—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning
    • G01C21/16—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/38—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system
    • G01S19/39—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/53—Determining attitude
    • G01S19/54—Determining attitude using carrier phase measurements; using long or short baseline interferometry
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
    • G01C21/10—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration
    • G01C21/12—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning
    • G01C21/16—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
    • G01C21/165—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation combined with non-inertial navigation instruments
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/32—Multimode operation in a single same satellite system, e.g. GPS L1/L2

Abstract

The integrated GPS/inertial navigation apparatus utilizes satellite signals received with two spatially-separated antennas to achieve improved heading estimates for a mobile platform. Each satellite signal comprises one or more component signals with each component signal having a different carrier frequency. The integrated GPS/inertial navigation apparatus consists of a receiver and an inertial navigation system. The receiver measures the carrier phase of each of one or more component signals of one or more satellite signals received by each of the two antennas during successive time periods of duration Tp. Phase measured during a Tp time period is called Tp-phase. Only one component signal of one satellite signal received by one antenna is measured during any Tp time period. The receiver utilizes the Tp-phases of each component signal obtained during a Tk time period to estimate the phase of the component signal at the end of the Tk time period, the estimated phase at the end of the Tk time period being called the Tk-phase. The inertial navigation system, comprising inertial sensors and a digital processor, utilizes the Tk-phases in determining the heading of the vehicle and the displacement of each of the two antennas from the inertial sensors of the inertial navigation system. The measured phase of a component signal is subject to error as a result of the satellite signal traversing the ionosphere.
The inertial navigation system achieves more accurate estimates of heading and antenna displacements by utilizing the Tk-phases in determining ionospheric corrections to phase.
CA002175945A 1995-08-07 1996-05-07 Integrated gps/inertial navigation apparatus providing improved heading estimates Expired - Fee Related CA2175945C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US08/511965 1995-08-07
US08/511,965 US5657025A (en) 1995-08-07 1995-08-07 Integrated GPS/inertial navigation apparatus providing improved heading estimates

Publications (2)

Publication Number Publication Date
CA2175945A1 true CA2175945A1 (en) 1997-02-08
CA2175945C CA2175945C (en) 1998-12-22

Family

ID=24037146

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002175945A Expired - Fee Related CA2175945C (en) 1995-08-07 1996-05-07 Integrated gps/inertial navigation apparatus providing improved heading estimates

Country Status (6)

Country Link
US (1) US5657025A (en)
EP (1) EP0763749A1 (en)
JP (1) JPH09178508A (en)
KR (1) KR970012260A (en)
CA (1) CA2175945C (en)
IL (1) IL118144A (en)

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Also Published As

Publication number Publication date
KR970012260A (en) 1997-03-29
IL118144A (en) 1998-08-16
JPH09178508A (en) 1997-07-11
IL118144A0 (en) 1996-09-12
EP0763749A1 (en) 1997-03-19
CA2175945C (en) 1998-12-22
US5657025A (en) 1997-08-12

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