EP0583972A1 - Verbesserungen in Bezug auf genaues Zielen - Google Patents

Verbesserungen in Bezug auf genaues Zielen Download PDF

Info

Publication number
EP0583972A1
EP0583972A1 EP93306477A EP93306477A EP0583972A1 EP 0583972 A1 EP0583972 A1 EP 0583972A1 EP 93306477 A EP93306477 A EP 93306477A EP 93306477 A EP93306477 A EP 93306477A EP 0583972 A1 EP0583972 A1 EP 0583972A1
Authority
EP
European Patent Office
Prior art keywords
target
gps
location
gps coordinates
aircraft
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.)
Withdrawn
Application number
EP93306477A
Other languages
English (en)
French (fr)
Inventor
Merrill J. Habbe
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.)
Texas Instruments Inc
Original Assignee
Texas Instruments 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 Texas Instruments Inc filed Critical Texas Instruments Inc
Publication of EP0583972A1 publication Critical patent/EP0583972A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41—WEAPONS
    • F41G—WEAPON SIGHTS; AIMING
    • F41G7/00—Direction control systems for self-propelled missiles
    • F41G7/34—Direction control systems for self-propelled missiles based on predetermined target position data
    • F41G7/346—Direction control systems for self-propelled missiles based on predetermined target position data using global navigation satellite systems, e.g. GPS, GALILEO, GLONASS
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41—WEAPONS
    • F41G—WEAPON SIGHTS; AIMING
    • F41G7/00—Direction control systems for self-propelled missiles
    • F41G7/007—Preparatory measures taken before the launching of the guided missiles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41—WEAPONS
    • F41G—WEAPON SIGHTS; AIMING
    • F41G7/00—Direction control systems for self-propelled missiles
    • F41G7/34—Direction control systems for self-propelled missiles based on predetermined target position data
    • F41G7/36—Direction control systems for self-propelled missiles based on predetermined target position data using inertial references

Definitions

  • This invention relates to a system and method for precision location of a target and precision delivery of a guided weapon to the located target under adverse as well as clear weather conditions.
  • a further concept is the use of a Global Positioning System (GPS) receiver within the guidance section of the weapon for steering to the target coordinates supplied by some on-board sensor. While this technique will operate in adverse weather conditions, techniques to accurately determine the target coordinates in a GPS reference frame are lacking.
  • GPS Global Positioning System
  • the most often discussed adverse weather technique for determining the target coordinates is with a high resolution radar using synthetic aperture radar (SAR) techniques, making range and monopulse measurements on the target and establishing the target location in GPS coordinates. While the range measurement is very accurate, the angle errors required to determine the position of the target in three dimensions are too inaccurate with radars on tactical aircraft. An angle error of one milliradian, one sigma, from distances of tens of kilometers causes target location errors of tens of meters.
  • SAR synthetic aperture radar
  • APG-70 which is used on the F-15 aircraft
  • APQ-164 which is used on the B-1B bomber
  • These images approach photographic quality and are presented to the pilot and/or weapon systems operator (WSO) using high resolution displays in the cockpit.
  • WSO weapon systems operator
  • the operator when presented the high resolution radar picture, can recognize the intended target on the display and can place a cursor (crosshairs) on the intended target.
  • the cursor location on the display designates to the weapons system computer the intended target whose location is to be determined.
  • the computer calculates the target position in a navigation reference system established by the aircraft inertial navigation system (INS).
  • INS aircraft inertial navigation system
  • an all weather target locating and weapon delivery system and method which provides the high precision required. This is accomplished by synergistically combining synthetic aperture radar (SAR) measurements and relative measurements from a Global Positioning System (GPS) tightly coupled to an Inertial Navigation System (INS) to precisely locate a target in GPS coordinates. Once the target location is precisely established, a weapon with a GPS Guidance Package, an Inertial Navigation System or a combination of the two is initialized with the target coordinates. Using standard guidance and control techniques, the weapon then guides to the target. This technique is capable of yielding homing accuracies equivalent to those achievable with present day precision guided smart weapons.
  • SAR synthetic aperture radar
  • GPS Global Positioning System
  • INS Inertial Navigation System
  • a high resolution SAR image of a target area is collected from a first location of the aircraft in space and presented to the pilot.
  • the pilot designates his target on the image.
  • the radar processor computes the location of the target using the radar measurements of range (R), azimuth angle ( ⁇ ) and elevation angle ( ⁇ ) and resolves the target coordinates into a local GPS reference frame.
  • the aircraft then flies to a second location and repeats the operation of generating the SAR image, designating the same target, and again computing the target location using the radar measurements of range, azimuth angle, and elevation angle.
  • the target location in a relative GPS frame of reference, is uniquely determined in the plane of measurements with accuracies of a few meters from a distance of up to about 50 kilometers.
  • a missile, glide bomb, or the like is then launched from the aircraft and guided to the target by a variety of means, including GPS guidance, inertial guidance or a combination of both.
  • Targets can be located and targeted in adverse weather conditions as well as clear weather conditions since the target location technique employs a radar and a GPS receiver integrated with an inertial navigation system, all of which can function in clear and adverse weather conditions.
  • weapon guidance is provided by a GPS receiver, an INS or a combination of both, all of which can function in clear and adverse weather conditions.
  • Weapon delivery accuracies of a few meters are achievable, equaling the precision weapon delivery of state of the art IR weapons with laser designation.
  • All of the information required to compute the target position is contained in a single set of radar measurements of range, azimuth angle, and elevation angle, in the absence of errors. However, measurement errors exist, so the computed target position is also in error. To reduce the error, an estimate of the target position is made using the radar measurements from each of a first aircraft position and a second aircraft position, given the GPS location of each aircraft position. When combined, these two measurement sets provide an estimate with smaller errors than that provided by either measurement set alone.
  • One common method referred to as the least squares method, selects a target location estimate such that the sum of the squared error between the estimated coordinates of the selected target and the measured values is minimized. If some measurement sets are more accurate than others, they can be weighted more heavily in the minimization process, resulting in a weighted least squares solution.
  • the small target location error requires very accurate knowledge of the position vector between the two aircraft positions.
  • the two aircraft positions along with the target position form a triangle in space.
  • Each side of the triangle is a measured quantity.
  • the two sides of the triangle that extend from the aircraft to the target are measured with accuracies of about 1 meter using the radar and the third side of the triangle is measured with an accuracy of a few centimeters by phase processing GPS signals from a set of GPS satellites.
  • the accuracy of the third side measurement, using the phase processing technique (cycle counting), when combined with the accurate radar range measurements, is the innovation that gives this weapon delivery concept its precision.
  • the technique for measuring the position vector between the two aircraft positions adds a cycle counting feature to a GPS receiver that is tightly coupled to an INS.
  • This is referred to in the literature as integrated navigation, or INAV.
  • INAV integrated navigation
  • GPS sensor data is integrated with data derived from inertial instruments.
  • inertial instruments if the output of the inertial unit is used to aid the GPS receiver tracking loops, very precise position and velocity information is achieved.
  • Conventional GPS uses information primarily from the GPS transmitted code to unambiguously obtain position information.
  • the GPS carrier frequency provides much more accurate relative position information, but it is ambiguous for relative position differences greater than its wavelength (19 centimeters in present practice).
  • a unique approach uses counts of GPS carrier cycles as a precision tape measure to obtain centimeter level accuracies and also to resolve the ambiguity.
  • the precision tape measure mode can be implemented in a moving platform.
  • the precision tape measure mode to measure distances between two points in space, is a relative measurement which is not degraded by any absolute position error of the GPS, provided these absolute errors remain correlated during the measurement interval in time and space.
  • a list of the correlated GPS errors and their respective correlation times or correlation distance are: Source Correlation Time or Distance Ionosphere/Troposphere 5-10 minutes Control/Space Segment 15-30 minutes Same Satellite Tracking 10-20 minutes Allowable Separation 50-75 miles
  • the absolute errors in the measured position vector between the two aircraft positions cancel.
  • the absolute errors using conventional GPS receivers, are on the order of fifteen to thirty meters. While this accuracy is sufficient for point to point navigation in most applications, it is not sufficient for precision weapon delivery.
  • the target location accuracy is established in a relative coordinate/frame of reference to a few centimeters.
  • Target location accuracies and weapon impact errors using the GPS-SAR precision targeting technique equal that of precision guided weapons at distances extending to 50 kilometers (KM). This distance is primarily determined by the range measurement accuracy which degrades as the range from the aircraft to the target increases. The range error is due to atmospheric uncertainties and the uncertainty of the speed of light through the atmosphere. The range extent is not regarded as a limitation of the concept because unpowered glide weapons have aerodynamic ranges well within this range. In addition, the accuracy of powered weapons from longer standoff ranges will only degrade slightly due to any increase in target location uncertainty.
  • the tape measure mode which is achieved through tight coupling between a GPS receiver with a carrier cycle counting feature and an INS. While this technique is exploited in the GPS-SAR precision targeting concept, it can also be applied to other problems. In particular, it can be used to sense aircraft motion during the synthetic aperture generation time for a SAR.
  • the aircraft trajectory must be known to a fraction of a wavelength to focus a high resolution radar image during a coherent data collection interval.
  • the wavelength is approximately 0.1 foot (about 3 cm) and a synthetic aperture length can exceed several miles.
  • the conventional approach is to measure the aircraft trajectory with a high quality INS. This approach limits the coherent data collection times because of uncorrected errors in inertial instrument biases and scale factors.
  • the aircraft position is calculated by a double integration of the accelerometer outputs. Because of the double integration, trajectory estimation errors grow as the square of the coherent data collection time, limiting map resolution unless some form of automatic focusing of the image is employed.
  • the GPS carrier cycle counting technique when applied to this problem, effectively bounds the position error across the synthetic aperture to approximately an inch. This dramatically reduces the reliance upon autofocus techniques.
  • FIGURE 1 there is shown an aircraft at a first position, L1, whereat the coordinates of the first position in a GPS are determined in standard manner from a set of at least four satellites, 3, of the GPS constellation.
  • the aircraft has a synthetic aperture radar (SAR) which images the target area, 4, therefrom to generate a SAR image, a target within the image then being designated by a cursor.
  • SAR synthetic aperture radar
  • the range, R1, and monopulse angles, ⁇ 1 and ⁇ 1, from position L1 to the target within the target area 4 are computed to establish the location of the target in GPS coordinates in three dimensions with associated errors in standard manner.
  • the aircraft 1 then flies to a second position L2.
  • the vector position of the aircraft at position L2 with respect to its previous position at L1 is measured.
  • the SAR obtains another high resolution SAR image of the same target area 5 and locates the designated target therein.
  • Coordinates of the second position in the GPS are again determined in three dimensions using the same satellite set 3 as discussed above. Again, the range, R2, and the monopulse angles, ⁇ 2 and ⁇ 2, from position L2 to the target within the target area 4 are computed to establish the location of the target in GPS coordinates in three dimensions with associated errors.
  • the precise location of the target is established at the aircraft position labeled L2 after collecting the radar measurements at points L1 and L2 and measuring the relative position difference between points L1 and L2 using the GPS cycle count method.
  • the computations to calculate the target position are as follows:
  • the position vector of the target with respect to point L1 be represented by the quantity P1
  • the position vector of the target with respect to point L2 be represented by the quantity P2
  • the vector difference between points L1 and L2 be represented by P2 -P 1.
  • a locally level frame such as North, East, and Down (NED).
  • the vectors P1 and P2 are computed using the radar range and monopulse angles, taken in an antenna reference frame, and a transformation matrix (A) that relates the antenna frame with the local level frame.
  • ⁇ P2> represents the best estimate of the location of the target with respect to the NED frame of the aircraft at point 2. This estimate is then extrapolated using the INAV on-board the aircraft and provided to the weapon 2 at release. At release, the weapon knows its present position and the position of the target.
  • a computer associated with the navigation system of the weapon which could be a GPS receiver only, an INS only, or a combined INAV, continues to calculate its present position relative to the target for the purpose of guiding the weapon to the target.
  • Any of several guidance laws commonly used in homing weapons can be used, such as 1) proportional guidance, 2) pursuit guidance or 3) a combination of the two with trajectory shaping.
  • Proportional guidance is the technique where the angle rates of the line of sight between the weapon and the target are determined and acceleration commands are sent to the control section of the weapon to drive the angle rates to zero. This places the weapon on a collision course with a target, even if the target is moving.
  • Pursuit guidance is another technique whereby the line of sight angles to the target are computed, rather than the angle rates, and acceleration commands are sent to the control section to drive the angles to zero. This points the velocity vector of the weapon directly at the present position of the target.
  • the best choice of guidance law consistent with this invention is one that shapes the trajectory of the weapon to impact the target at a steep vertical angle. The reason for this is to minimize the miss distance at impact.
  • the least accurate component of the position of the target is in the direction perpendicular to the plane containing the measurements. For most geometries, this will be in the near vertical direction.
  • Trajectory shaping is a simple matter with this technique because the on-board computer of the weapon can calculate range-to-go, since it knows its continually updated position and the position of the target.
  • Guidance sections of most currently operational seekers that employ electro-optical (EO) or infrared (IR) seekers have no range information and can only discern angles to the target.
  • pseudo and delta range measurements from a GPS receiver with carrier phase tracking loops are combined with the position, velocity and orientation INS data of the aircraft in a common Kalman filter.
  • the measurements from the GPS receiver are aided by code and carrier loop data. This forms a tightly coupled system that is optimum for calibrating the bias of the IMU and scale factor errors. It also allows for rate aiding of the code and carrier loops during aircraft dynamics.
  • the Kalman filter calibrates and aligns the data received therein from the INS and GPS and provides calibration and alignment information to the INS.
  • the INS than provides calibrated and aligned information to the weapon for guidance thereof to the target.
  • the GPS signal is modulated onto a 1.576 GHz, L band, carrier signal whose wavelength is 19 centimeters.
  • a GPS receiver Once a GPS receiver has established lock on a satellite signal, it can count the number of carrier cycles that have occurred in a finite interval of time. Since carrier tracking can be established under good signal conditions to an error of 5 degrees, one sigma, the accuracy of this count along the line of sight to a satellite is of the order of 0.26 centimeters. When resolved into a navigation frame of reference, this translates into a position increment of .84 centimeters, assuming a geometric dilution of precision of 3.14. The magnitude of this error is about 100 times less than that induced by code phase error, forming the basis of a highly accurate relative positioning system.
  • cycle slips are equivalent to missing or dropping the counts of the number of carrier cycles. This can happen for many reasons, the primary reason being satellite obscuration, such as aircraft wing shading or electronic obstruction, such as the temporary loss of signal by sudden antenna motion. In such cases, there will be a miscount of the number of cycles and thus a corresponding position error.
  • satellite obscuration such as aircraft wing shading or electronic obstruction, such as the temporary loss of signal by sudden antenna motion. In such cases, there will be a miscount of the number of cycles and thus a corresponding position error.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • General Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Position Fixing By Use Of Radio Waves (AREA)
  • Radar Systems Or Details Thereof (AREA)
EP93306477A 1992-08-17 1993-08-17 Verbesserungen in Bezug auf genaues Zielen Withdrawn EP0583972A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US93107892A 1992-08-17 1992-08-17
US931078 1992-08-17

Publications (1)

Publication Number Publication Date
EP0583972A1 true EP0583972A1 (de) 1994-02-23

Family

ID=25460191

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93306477A Withdrawn EP0583972A1 (de) 1992-08-17 1993-08-17 Verbesserungen in Bezug auf genaues Zielen

Country Status (1)

Country Link
EP (1) EP0583972A1 (de)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0649034A2 (de) * 1993-10-18 1995-04-19 Hughes Aircraft Company SAR/GPS inertielles Verfahren zur Distanzmessung
WO1996025641A2 (en) * 1995-02-14 1996-08-22 Bofors Ab Method and apparatus for radial thrust trajectory correction of a ballistic projectile
EP0747657A2 (de) * 1995-06-05 1996-12-11 Hughes Missile Systems Company Selbst-überwachende GPS gebrauchende Waffenlenkung
WO2000003193A1 (en) * 1998-07-09 2000-01-20 Raytheon Company Geographically limited missile
GB2341995A (en) * 1998-07-31 2000-03-29 Litton Systems Inc INS/GPS motion compensation for synthetic aperture radar
US6142411A (en) * 1997-06-26 2000-11-07 Cobleigh; Nelson E. Geographically limited missile
EP1480000A1 (de) * 2003-05-19 2004-11-24 Giat Industries Verfahren zur Lenkung der Flugbahn eines drehenden Geschosses
WO2005022070A2 (en) * 2003-05-23 2005-03-10 Raytheon Company Integrity bound situational awareness and weapon targeting
WO2005052491A3 (en) * 2003-05-23 2005-09-09 Raytheon Co Munition with integrity gated go/no-go decision
US7655062B2 (en) 2005-02-10 2010-02-02 Euro-Pro Operating, Llc Filter assembly for a vacuum cleaner
US7728264B2 (en) * 2005-10-05 2010-06-01 Raytheon Company Precision targeting
WO2010063844A1 (fr) * 2008-12-05 2010-06-10 Thales Procede de geo-localisation d'un objet par multitelemetrie
FR2939517A1 (fr) * 2008-12-05 2010-06-11 Thales Sa Procede de geo-localisation d'un objet par multitelemetrie
CN108919220A (zh) * 2018-07-06 2018-11-30 西安电子科技大学 基于嵌入式gpu的弹载sar前侧视成像方法
WO2019066698A1 (en) * 2017-09-29 2019-04-04 Saab Ab METHOD OF DETERMINING THE BASIC LINE OF SYNTHETIC OPENING OF A SAR USING A GNSS

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3145374A1 (de) * 1981-11-14 1983-06-01 Messerschmitt-Bölkow-Blohm GmbH, 8000 München Verfahren und einrichtung zur bekaempfung von bodenzielen mittels flugkoerper
DE3430888A1 (de) * 1984-08-22 1986-03-06 Messerschmitt-Bölkow-Blohm GmbH, 8012 Ottobrunn Einrichtung zur detektion und bekaempfung untergezogener bodenziele
DE3540808A1 (de) * 1984-08-22 1987-05-21 Messerschmitt Boelkow Blohm Einrichtung zur detektion und bekaempfung untergezogener bodenziele
US4741245A (en) * 1986-10-03 1988-05-03 Dkm Enterprises Method and apparatus for aiming artillery with GPS NAVSTAR
FR2670037A1 (fr) * 1990-12-04 1992-06-05 Thomson Csf Dispositif de designation d'objectif.
EP0547637A1 (de) * 1991-12-19 1993-06-23 Hughes Aircraft Company Autonomer Präzisionswaffenabschuss unter Verwendung eines Radars mit synthetischer Apertur

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3145374A1 (de) * 1981-11-14 1983-06-01 Messerschmitt-Bölkow-Blohm GmbH, 8000 München Verfahren und einrichtung zur bekaempfung von bodenzielen mittels flugkoerper
DE3430888A1 (de) * 1984-08-22 1986-03-06 Messerschmitt-Bölkow-Blohm GmbH, 8012 Ottobrunn Einrichtung zur detektion und bekaempfung untergezogener bodenziele
DE3540808A1 (de) * 1984-08-22 1987-05-21 Messerschmitt Boelkow Blohm Einrichtung zur detektion und bekaempfung untergezogener bodenziele
US4741245A (en) * 1986-10-03 1988-05-03 Dkm Enterprises Method and apparatus for aiming artillery with GPS NAVSTAR
FR2670037A1 (fr) * 1990-12-04 1992-06-05 Thomson Csf Dispositif de designation d'objectif.
EP0547637A1 (de) * 1991-12-19 1993-06-23 Hughes Aircraft Company Autonomer Präzisionswaffenabschuss unter Verwendung eines Radars mit synthetischer Apertur

Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0649034A3 (de) * 1993-10-18 1995-08-02 Hughes Aircraft Co SAR/GPS inertielles Verfahren zur Distanzmessung.
EP0649034A2 (de) * 1993-10-18 1995-04-19 Hughes Aircraft Company SAR/GPS inertielles Verfahren zur Distanzmessung
WO1996025641A2 (en) * 1995-02-14 1996-08-22 Bofors Ab Method and apparatus for radial thrust trajectory correction of a ballistic projectile
WO1996025641A3 (en) * 1995-02-14 1996-09-26 Bofors Ab Method and apparatus for radial thrust trajectory correction of a ballistic projectile
EP0747657A2 (de) * 1995-06-05 1996-12-11 Hughes Missile Systems Company Selbst-überwachende GPS gebrauchende Waffenlenkung
EP0747657A3 (de) * 1995-06-05 1998-12-02 Raytheon Company Selbst-überwachende GPS gebrauchende Waffenlenkung
US6142411A (en) * 1997-06-26 2000-11-07 Cobleigh; Nelson E. Geographically limited missile
WO2000003193A1 (en) * 1998-07-09 2000-01-20 Raytheon Company Geographically limited missile
AU740261B2 (en) * 1998-07-09 2001-11-01 Raytheon Company Geographically limited missile
GB2341995A (en) * 1998-07-31 2000-03-29 Litton Systems Inc INS/GPS motion compensation for synthetic aperture radar
GB2341995B (en) * 1998-07-31 2003-02-19 Litton Systems Inc Enhanced motion compensation technique in synthetic aperture radar systems
EP1480000A1 (de) * 2003-05-19 2004-11-24 Giat Industries Verfahren zur Lenkung der Flugbahn eines drehenden Geschosses
FR2855258A1 (fr) * 2003-05-19 2004-11-26 Giat Ind Sa Procede de controle de la trajectoire d'un projectile girant
US7105790B2 (en) 2003-05-19 2006-09-12 Giat Industries Process to control the trajectory of a spinning projectile
WO2005022070A3 (en) * 2003-05-23 2005-09-01 Raytheon Co Integrity bound situational awareness and weapon targeting
WO2005052491A3 (en) * 2003-05-23 2005-09-09 Raytheon Co Munition with integrity gated go/no-go decision
US6952001B2 (en) * 2003-05-23 2005-10-04 Raytheon Company Integrity bound situational awareness and weapon targeting
WO2005022070A2 (en) * 2003-05-23 2005-03-10 Raytheon Company Integrity bound situational awareness and weapon targeting
US7207517B2 (en) 2003-05-23 2007-04-24 Raytheon Company Munition with integrity gated go/no-go decision
US7367525B2 (en) 2003-05-23 2008-05-06 Raytheon Company Munition with integrity gated go/no-go decision
US7655062B2 (en) 2005-02-10 2010-02-02 Euro-Pro Operating, Llc Filter assembly for a vacuum cleaner
US7728264B2 (en) * 2005-10-05 2010-06-01 Raytheon Company Precision targeting
WO2010063844A1 (fr) * 2008-12-05 2010-06-10 Thales Procede de geo-localisation d'un objet par multitelemetrie
FR2939517A1 (fr) * 2008-12-05 2010-06-11 Thales Sa Procede de geo-localisation d'un objet par multitelemetrie
US8630804B2 (en) 2008-12-05 2014-01-14 Thales Method for geolocating an object by multitelemetry
WO2019066698A1 (en) * 2017-09-29 2019-04-04 Saab Ab METHOD OF DETERMINING THE BASIC LINE OF SYNTHETIC OPENING OF A SAR USING A GNSS
US10788587B2 (en) 2017-09-29 2020-09-29 Saab Ab Method for determining a synthetic aperture of a SAR using GNSS
CN108919220A (zh) * 2018-07-06 2018-11-30 西安电子科技大学 基于嵌入式gpu的弹载sar前侧视成像方法
CN108919220B (zh) * 2018-07-06 2022-05-17 西安电子科技大学 基于嵌入式gpu的弹载sar前侧视成像方法

Similar Documents

Publication Publication Date Title
KR960014821B1 (ko) 합성 어레이 레이다를 사용하는 자율 정밀도 무기 수송 시스템 및 방법
EP1949016B1 (de) Präzisions-targeting
JP2625360B2 (ja) 全体的位置決定システムを使用する相対的誘導方法
US4489322A (en) Radar calibration using direct measurement equipment and oblique photometry
US9110170B1 (en) Terrain aided navigation using multi-channel monopulse radar imaging
US6512976B1 (en) Method and system for terrain aided navigation
EP0583972A1 (de) Verbesserungen in Bezug auf genaues Zielen
EP0093603B1 (de) Feuerleiteinrichtung für bewegliche Ziele
JP2971806B2 (ja) 自己探索型相対ｇｐｓ武器誘導システム
USRE40801E1 (en) GPS airborne target geolocating method
US5969676A (en) Radio frequency interferometer and laser rangefinder/destination base targeting system
AU2003290935B2 (en) All-weather precision guidance and navigation system
EP1860456A1 (de) Verfahren und Systeme zur radarunterstützten Flugzeugpositionierung für Näherungen und Landungen
CN101010563A (zh) 组合激光系统和全球导航卫星系统
US6211816B1 (en) Process and apparatus for target or position reconnaissance
EP1117972B1 (de) Hochgenauer weitreichender optisch gestützter inertial gelenkter flugkörper
WO2001077704A2 (en) Self-calibration of an array of imaging sensors
US5373318A (en) Apparent size passive range method
RU2247921C2 (ru) Способ ориентирования на местности и устройство для его осуществления
Brown et al. Precision kinematic alignment using a low-cost GPS/INS system
US5367333A (en) Passive range measurement system
CN113137966B (zh) 一种利用惯组和激光测距的组合导航自主定位方法
US20240128993A1 (en) Coordinate Frame Projection Using Multiple Unique Signals Transmitted from a Localized Array of Spatially Distributed Antennas
Ioannidis et al. GPS exploitation for precision targeting a relative targeting system
Brown et al. Precision Targeting Using GPS/Inertial-Aided Sensors

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB IT

17P Request for examination filed

Effective date: 19940808

17Q First examination report despatched

Effective date: 19951228

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19960508