EP1386179A1 - Radar system for obstacle warning and imaging of the surface of the earth - Google Patents

Radar system for obstacle warning and imaging of the surface of the earth

Info

Publication number
EP1386179A1
EP1386179A1 EP02732400A EP02732400A EP1386179A1 EP 1386179 A1 EP1386179 A1 EP 1386179A1 EP 02732400 A EP02732400 A EP 02732400A EP 02732400 A EP02732400 A EP 02732400A EP 1386179 A1 EP1386179 A1 EP 1386179A1
Authority
EP
European Patent Office
Prior art keywords
radar system
antenna elements
radar
missile
antenna
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Withdrawn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
EP02732400A
Other languages
German (de)
French (fr)
Inventor
Helmut Klausing
Horst Kaltschmidt
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.)
Airbus Defence and Space GmbH
Original Assignee
EADS Deutschland GmbH
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 EADS Deutschland GmbH filed Critical EADS Deutschland GmbH
Publication of EP1386179A1 publication Critical patent/EP1386179A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • 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
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
    • G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
    • G01S13/904—SAR modes
    • G01S13/9043—Forward-looking SAR
    • 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
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
    • G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
    • G01S13/904—SAR modes

Definitions

  • the invention relates to a radar system for obstacle warning and imaging of the earth's surface according to the preamble of claim 1.
  • a radar system for obstacle warning and imaging of the earth's surface is known from DE 40 07 612 C1.
  • a forward light radar is described there, which is attached to the bow of a missile and depicts the sector area in front in two dimensions.
  • the forward-looking radar described here comprises an antenna consisting of a plurality of antenna elements arranged next to one another for transmitting and receiving.
  • a synthetic aperture is generated by successively actuating and scanning the individual antenna elements, as is known from the SAR principle.
  • the radar signals are evaluated in such a way that each antenna element is evaluated individually, with digital processing being carried out for each angular range by correlating a specific, predetermined reference function.
  • One disadvantage is the poor angular resolution. Further evaluation methods are from Fan, Z.F.
  • the radar system known from DE 40 07 612 C1 proves to be disadvantageous in that it can only represent the sector area in front. Areas adjacent to the side must be mapped using additionally installed antenna systems. This means a considerable installation effort. In addition, complicated evaluation procedures are necessary in order to be able to depict the various sector areas in a pictorial manner.
  • the object underlying the invention is therefore to specify a single radar system with which a side view is possible in addition to the forward view.
  • the antenna elements are attached to the missile along the curved missile contour, a SAR processor being present which evaluates the information obtained from the antenna elements and displays them as processed radar images on board the missile in a virtual cockpit.
  • the antenna elements can now advantageously be controlled according to the sector area to be imaged.
  • the information obtained from the respective antenna elements can advantageously be evaluated using the linear SAR method or the ROSAR method.
  • the synthetic aperture known in the conventional SAR method is not generated in the proposed radar system by e.g. the missile moves relative to the target object, but rather the individual antenna elements, which are arranged adjacent to one another, are electronically controlled and scanned in succession. Also in the evaluation according to the ROSAR method, the rotating antenna movement is simulated by actuating and scanning adjacent antenna elements at different times.
  • the antenna elements are spatially arranged to generate a three-dimensional radar system.
  • the antenna elements are combined into two-dimensional antenna arrays, which, adapted to the curved contour of the missile, are attached to the missile.
  • An advantage of this spatial arrangement of the two-dimensional antenna array on the contour of the missile is that the scanning plane of the antenna elements is decoupled from the flight plane of the missile. This means that the scanning plane can be kept constant regardless of the flight plane. In particular in the event of strong air turbulence or when cornering, the object to be imaged may disappear from the field of view of the radar. This is prevented with the two-dimensional antenna array which is advantageously arranged along the contour of the missile.
  • the radar system according to the invention can advantageously also be used on combat and / or reconnaissance drones or ships. It can be used as an all-weather system and allows e.g. Missiles can land and take off safely in any weather, even on airfields that are not specially equipped.
  • FIG. 1 shows an embodiment of the installation of the antenna elements in the area of a radar nose of a missile in a schematic representation
  • FIG. 1 shows an embodiment of an electrical block diagram according to FIG. 1,
  • FIG. 3 shows a diagram with respect to the sequence of transmit and receive signals according to the exemplary embodiment according to FIG. 1,
  • FIG. 5 shows a schematic diagram relating to an exemplary embodiment for an antenna arrangement based on the ROSAR principle and the linear SAR principle.
  • Fig. 6 shows an embodiment of a planar arrangement of the antenna elements in the region of a radar nose of a missile in a schematic representation.
  • Fig. 1 shows a schematic representation of a first embodiment of the arrangement of the antenna elements along the contour of the missile.
  • Transmitting and receiving antenna elements A are mounted in the area of the radar nose RN at a distance ⁇ b on a curve that corresponds to the contour K, e.g. Missile corresponds.
  • ⁇ b is e.g. ⁇ / 2, where ⁇ is the wavelength of the transmission signal.
  • FIG. 4 shows two further exemplary arrangements of the antenna elements, the bottom view of a missile being shown as an example. Of course, this arrangement can also be transferred to the top or side view of the missile.
  • the antenna elements A are arranged along the contour of the missile towards the tip of the radar nose RN of the missile.
  • the arrangement of the antenna elements A along the contour of the missile can take place as any curve.
  • FIG. 4 shows a further exemplary arrangement possibility of the antenna elements A along the contour of the missile.
  • the arrangement of antenna elements A appears as a circle, although in reality antenna elements A are arranged along a curved curve that adapts to the contour of the missile.
  • FIG. 2 shows in a block diagram the electrical connection of an exemplary embodiment according to FIG. 1.
  • the transmitting and receiving antenna elements A are each connected to a phase-stable HF transmitter S during a time ⁇ t and then to a receiver E during the time ⁇ t.
  • the continuous, rotational movement of the antennas is electronically controlled by ten of the RF transmitter S from one antenna element A to the next.
  • a reflection point to be imaged on the runway (not shown) or a point (not shown) in its vicinity receives a transmission signal which changes in time in phase.
  • the receiver E In the receiving phase, the receiver E then also receives a signal that has changed in phase.
  • a positive time-varying Doppler shift occurs as long as the antenna scan moves towards the reflex point.
  • the reflection of a reflection point is determined by cross-correlation of the received signal mixture with the reference signal of this reflection point, which is taken from the reference signal memory RS, carried out in a correlator K.
  • the individual reference signals - apart from special cases - differ for a range ring only by the angular position, so that a separate reference signal does not have to be stored and correlated for each reflection point.
  • the problem with the radar system proposed here is that the distance changes quickly due to the high airspeed, which causes image distortion.
  • the electrical scanning offers an extreme shortening of the entire scanning cycle, so that the effect of the distance change leads to negligible image distortion. This saves computational image correction.
  • FIG. 3 shows an exemplary embodiment for a course of transmit and receive signals with their "send” and “receive” intervals.
  • the repeating chronological course of the activation of adjacent antenna elements is shown on the abscissa.
  • the first antenna element transmits the short transmission pulse S1 during the time ⁇ t s .
  • the first antenna element receives the transmission signal El.
  • the ordinate plots the amplitude of the transmission and reception signal without units.
  • pilot visual equipment be available in which the radar information obtained can be displayed.
  • a virtual cockpit in which e.g. a three-dimensional computer image of the surroundings is imaged.
  • a current obstacle display in the virtual cockpit can significantly increase the efficiency of computer-oriented flight guidance.
  • the virtual cockpit requires current location information through GPS. Because of the necessary position accuracy, the more suitable "differential GPS" is proposed for this. If there is a need to transmit position or obstacle data efficiently, either an HFA RF data link or mobile communication via GSM or satellite network is suggested.
  • the use of mobile communication enables two-way communication, i.e. Full duplex operation and group communication.
  • the advantage of HF / VHF communication is the independence of available infrastructures. Self-sufficient communication options are particularly necessary for military operations in partially unknown areas.
  • FIG. 5 shows a further exemplary embodiment of the radar system according to the invention.
  • the section through the nose of a missile is shown schematically.
  • the radar information of the antenna elements of that section KA of the antenna Arrays on the circular bow, for example, are advantageously evaluated using the ROSAR method.
  • the section LA of the antenna array which adjoins this section KA is advantageously evaluated according to the linear SAR method.
  • a radar view is possible with the radar system according to the invention without, for example, a "squint mode" would be required, with which losses in the resolution or an increased signal processing outlay would be connected due to the oblique antenna viewing angle.
  • FIG. 6 shows a further exemplary embodiment of the radar system according to the invention.
  • the radar nose RN of a missile is shown in a schematic representation in a side view.
  • the antenna elements A are arranged flat according to the contour K of the missile.
  • the antenna elements A are combined to form antenna arrays, which are not shown for reasons of clarity.
  • the arrangement of the antenna elements A shown is only an example. A different arrangement of the antenna elements A is of course also possible.

Abstract

The invention relates to a radar system for active obstacle warning and imaging of the surface of the earth, working in the pulse frequency or FM-CW range and may be applied to online operation in real-time, comprising a number of antenna elements, for transmission and receiving of radar signals, arranged on the fuselage of an aircraft and which may be operated sequentially, thus generating a synthetic aperture by means of periodic transmission and receiving from the antenna elements. The antenna elements are arranged along the curved surface of the aircraft contour, an SAR processor is provided to analyse the information obtained from the antenna elements and displayed as processed radar images on board the aircraft in a virtual cockpit.

Description

Radarsystem zur Hinderniswarnung und Abbildung der ErdoberflächeRadar system for obstacle warning and imaging of the earth's surface
Die Erfindung betrifft ein Radarsystem zur Hinderniswarnung und Abbildung der Erdoberfläche gemäß dem Oberbegriff des Patentanspruchs 1.The invention relates to a radar system for obstacle warning and imaging of the earth's surface according to the preamble of claim 1.
Ein Radarsystem zur Hinderniswarnung und Abbildung der Erdoberfläche ist aus DE 40 07 612 C1 bekannt. Dort wird ein Vorwärtsicht-Radar beschrieben, welches am Bug eines Flugkörpers angebracht ist und den vorausliegenden Sektorbereich zwei- dimensional abbildet. Das beschriebene Vorwärtssicht-Radar umfaßt dabei eine An- tenne bestehend aus mehreren nebeneinander angeordneten Antennenelementen zum Senden und Empfangen. Mittel eines zeitlich nacheinander erfolgenden An- steuerung und Abtastung der einzelnen Antennenelemente wird eine synthetische Apertur erzeugt, wie sie aus dem SAR-Prinzip bekannt ist. Die Auswertung der Radarsignale erfolgt dabei derart, dass jedes Antennenelement einzeln ausgewertet wird, wobei durch Korrelation einer speziellen, vorgegebenen Referenzfunktion für jeden Winkelbereich eine digitale Verarbeitung durchgeführt wird. Ein Nachteil dabei ist die schlechte Winkelauflösung. Weitere Auswerteverfahren sind von Fan, Z.F. et.al in „High Resolution Imaging of Objects at Ka Band"; IEEE Trans, on Aerospace and Electronic Systems ,1995, Vol.31 , Heft 4, S.1348-1352 und Li, H.-J. et.al in „Nonuniformly Spaced Array Imaging"; IEEE Trans, on Antennas and Propagation, 1993, Vol.41 , Heft 3, Seite 278-286 bekannt.A radar system for obstacle warning and imaging of the earth's surface is known from DE 40 07 612 C1. A forward light radar is described there, which is attached to the bow of a missile and depicts the sector area in front in two dimensions. The forward-looking radar described here comprises an antenna consisting of a plurality of antenna elements arranged next to one another for transmitting and receiving. A synthetic aperture is generated by successively actuating and scanning the individual antenna elements, as is known from the SAR principle. The radar signals are evaluated in such a way that each antenna element is evaluated individually, with digital processing being carried out for each angular range by correlating a specific, predetermined reference function. One disadvantage is the poor angular resolution. Further evaluation methods are from Fan, Z.F. et.al in "High Resolution Imaging of Objects at Ka Band"; IEEE Trans, on Aerospace and Electronic Systems, 1995, Vol.31, Issue 4, pp. 1348-1352 and Li, H.-J. et.al in "Nonuniformly Spaced Array Imaging"; IEEE Trans, on Antennas and Propagation, 1993, Vol.41, Issue 3, pages 278-286.
Das aus DE 40 07 612 C1 bekannte Radarsystem erweist sich insofern als nachteilhaft, da es lediglich den vorausliegenden Sektorbereich abbilden kann. Seitlich be- nachbarte Gebiete müssen mittels zusätzlich installierter Antennensysteme abgebildet werden. Dies bedeutet einen erheblichen Installationsaufwand. Außerdem sind komplizierte Auswerteverfahren nötig, um die verschiedenen Sektorbereiche bildhaft darstellen zu können. Der Erfindung zugrundeliegenden Aufgabe ist es daher, ein einziges Radarsystem anzugeben, mit dem neben der Vorwärtsicht auch eine Seitensicht möglich ist.The radar system known from DE 40 07 612 C1 proves to be disadvantageous in that it can only represent the sector area in front. Areas adjacent to the side must be mapped using additionally installed antenna systems. This means a considerable installation effort. In addition, complicated evaluation procedures are necessary in order to be able to depict the various sector areas in a pictorial manner. The object underlying the invention is therefore to specify a single radar system with which a side view is possible in addition to the forward view.
Diese Aufgabe wird mit dem Radarsystem gemäß Patentanspruch 1 gelöst. Vorteil- hafte Ausführungen der Erfindung sind Gegenstand von Unteransprüchen.This object is achieved with the radar system according to claim 1. Advantageous embodiments of the invention are the subject of dependent claims.
Gemäß der Erfindung sind die Antennenelemente entlang der gekrümmten Flugkörperkontur am Flugkörper angebracht, wobei ein SAR-Prozessor vorhanden ist, der die von den Antennenelementen gewonnenen Informationen ausgewertet und als prozessierte Radarbilder an Bord des Flugkörpers in einem virtuellen Cockpit darstellt.According to the invention, the antenna elements are attached to the missile along the curved missile contour, a SAR processor being present which evaluates the information obtained from the antenna elements and displays them as processed radar images on board the missile in a virtual cockpit.
Die Antennenelemente können nun vorteilhaft entsprechend des abzubildenden Sektorbereichs angesteuert werden. Die dabei von den jeweiligen Antennenelemen- ten gewonnenen Informationen können vorteilhaft nach dem linearen SAR-Verfahren oder nach dem ROSAR-Verfahren ausgewertet werden.The antenna elements can now advantageously be controlled according to the sector area to be imaged. The information obtained from the respective antenna elements can advantageously be evaluated using the linear SAR method or the ROSAR method.
Die beim herkömmlichen SAR-Verfahren bekannte synthetische Apertur wird in dem vorgeschlagenen Radarsystem nicht dadurch erzeugt, dass sich z.B. der Flugkörper relativ gegenüber dem Zielobjekt bewegt, sondern die einzelnen, zueinander benachbart angeordneten Antennenelemente werden zeitlich nacheinander elektronisch angesteuert und abgetastet. Auch bei der Auswertung nach dem ROSAR-Verfahren wird die rotierende Antennenbewegung durch das zeitlich versetzte Ansteuern und Abtasten benachbarter Antennenelemente simuliert.The synthetic aperture known in the conventional SAR method is not generated in the proposed radar system by e.g. the missile moves relative to the target object, but rather the individual antenna elements, which are arranged adjacent to one another, are electronically controlled and scanned in succession. Also in the evaluation according to the ROSAR method, the rotating antenna movement is simulated by actuating and scanning adjacent antenna elements at different times.
In einer vorteilhaften Ausführung der Erfindung sind die Antennenelemente zur Erzeugung eines dreidimensionalen Radarsystems räumlich angeordnet. Die Antennenelemente sind dabei zu zweidimensionalen Antennenarrays zusammengefaßt, welche, an die gekrümmte Kontur des Flugkörpers angepaßt, am Flugkörper ange- bracht sind. Ein Vorteil dieser räumlichen Anordnung des zweidimensionalen Antennenarrays an die Kontur des Flugkörpers ist, dass die Abtastebene der Antennenelemente von der Flugebene des Flugkörpers entkoppelt ist. Dies bedeutet, dass die Abtastebene unabhängig von der Flugebene konstant gehalten werden kann. Insbesondere bei starken Luftturbulenzen oder beim Kurvenflug kann es vorkommen, dass das abzubildende Objekt aus dem Sichtbereich des Radars verschwindet. Mit dem vorteilhaft entlang der Kontur des Flugkörpers angeordneten zweidimensionalen Antennenarray wird dies verhindert.In an advantageous embodiment of the invention, the antenna elements are spatially arranged to generate a three-dimensional radar system. The antenna elements are combined into two-dimensional antenna arrays, which, adapted to the curved contour of the missile, are attached to the missile. An advantage of this spatial arrangement of the two-dimensional antenna array on the contour of the missile is that the scanning plane of the antenna elements is decoupled from the flight plane of the missile. This means that the scanning plane can be kept constant regardless of the flight plane. In particular in the event of strong air turbulence or when cornering, the object to be imaged may disappear from the field of view of the radar. This is prevented with the two-dimensional antenna array which is advantageously arranged along the contour of the missile.
Das erfindungsgemäße Radarsystem ist vorteilhaft auch auf Kampf- und/oder Aufklärungsdrohnen oder Schiffen einsetzbar. Es ist dabei jeweils als Allwettersichtsystem anwendbar und erlaubt z.B. Flugkörpern auch auf nicht speziell ausgerüsteten Flugplätzen ein sicheres Landen und Starten bei jedem Wetter.The radar system according to the invention can advantageously also be used on combat and / or reconnaissance drones or ships. It can be used as an all-weather system and allows e.g. Missiles can land and take off safely in any weather, even on airfields that are not specially equipped.
Die Erfindung sowie weitere vorteilhafte Ausgestaltungen werden im weiteren anhand von Zeichnungen näher erläutert. Es zeigen:The invention and further advantageous embodiments are explained in more detail below with reference to drawings. Show it:
Fig.1 ein Ausführungsbeispiel für den Einbau der Antennenelemente in den Be- reich einer Radarnase eines Flugkörpers in schematischer Darstellung,1 shows an embodiment of the installation of the antenna elements in the area of a radar nose of a missile in a schematic representation,
Fig. 2 ein Ausführungsbeispiel eines elektrischen Blockschaltbildes gemäß Fig.1 ,2 shows an embodiment of an electrical block diagram according to FIG. 1,
Fig. 3 ein Diagramm bezüglich der Aufeinanderfolge von Sende- und Empfangs- Signalen gemäß dem Ausführungsbeispiel nach Fig.1 ,3 shows a diagram with respect to the sequence of transmit and receive signals according to the exemplary embodiment according to FIG. 1,
Fig. 4 Ausführungsbeispiele der Anordnung von Antennenelementen in verschieden geformte Radarnasen,4 embodiments of the arrangement of antenna elements in differently shaped radar noses,
Fig. 5 ein Schemabild bezüglich eines Ausführungsbeispiels für eine Antennenanordnung nach dem ROSAR-Prinzip und dem linearen SAR-Prinzip. Fig. 6 ein Ausführungsbeispiel für eine flächenhafte Anordnung der Antennenelemente im Bereich einer Radarnase eines Flugkörpers in schematischer Darstellung.5 shows a schematic diagram relating to an exemplary embodiment for an antenna arrangement based on the ROSAR principle and the linear SAR principle. Fig. 6 shows an embodiment of a planar arrangement of the antenna elements in the region of a radar nose of a missile in a schematic representation.
Fig. 1 zeigt in einer schematischen Darstellung ein erstes Ausführungsbeispiel der Anordnung der Antennenelemente entlang der Kontur des Flugkörpers. Sende- und Empfangsantennenelemente A werden im Bereich der Radarnase RN in einem Ab- stand Δb auf einer Kurve montiert, die der Kontur K, des z.B. Flugkörpers entspricht. Δb beträgt dabei z.B. λ/2, wobei λ die Wellenlänge des Sendesignals ist.Fig. 1 shows a schematic representation of a first embodiment of the arrangement of the antenna elements along the contour of the missile. Transmitting and receiving antenna elements A are mounted in the area of the radar nose RN at a distance Δb on a curve that corresponds to the contour K, e.g. Missile corresponds. Δb is e.g. λ / 2, where λ is the wavelength of the transmission signal.
Fig. 4 zeigt zwei weitere beispielhafte Anordnungen der Antennenelemente, wobei jeweils beispielhaft die Unteransicht eines Flugkörpers abgebildet ist. Selbstverständ- lieh kann diese Anordnung auch auf die Ober- oder Seitenansicht des Flugkörpers übertragen werden.FIG. 4 shows two further exemplary arrangements of the antenna elements, the bottom view of a missile being shown as an example. Of course, this arrangement can also be transferred to the top or side view of the missile.
In der linken Anordnung sind die Antennenelemente A entlang der Kontur des Flugkörpers hin zu der Spitze der Radarnase RN des Flugkörpers angeordnet. Die Anordnung der Antennenelemente A entlang der Kontur des Flugkörpers kann dabei als beliebige Kurve erfolgen.In the left arrangement, the antenna elements A are arranged along the contour of the missile towards the tip of the radar nose RN of the missile. The arrangement of the antenna elements A along the contour of the missile can take place as any curve.
Die rechte Darstellung in Fig. 4 zeigt eine weitere beispielhafte Anordnungsmöglichkeit der Antennenelemente A entlang der Kontur des Flugkörpers. Aus Gründen der Darstellung erscheint die Anordnung der Antennenelemente A dabei als Kreis, obwohl die Antennenelemente A in Realität entlang einer gekrümmten Kurve, die sich an die Kontur des Flugkörpers anpaßt, angeordnet sind.The right-hand illustration in FIG. 4 shows a further exemplary arrangement possibility of the antenna elements A along the contour of the missile. For the sake of illustration, the arrangement of antenna elements A appears as a circle, although in reality antenna elements A are arranged along a curved curve that adapts to the contour of the missile.
Fig. 2 zeigt in einem Blockschaltbild die elektrische Verschaltung eines Ausführungsbeispiels gemäß Fig. 1. Die Sende- und Empfangsantennenelemente A jeweils während einer Zeit Δt an einen phasenstabilen HF-Sender S und danach während der Zeit Δt an einen Empfänger E geschaltet. Die z.B. beim ROSAR-Prinzip kontinuierliche, rotatorische Bewegung der Antennen wird hier elektronisch durch Weiterschal- ten des HF-Senders S von einem Antennenelement A zum nächsten ausgeführt. Dabei erhält ein abzubildender Reflexpunkt auf der Landebahn (nicht dargestellt) oder ein Punkt (nicht dargestellt) in ihrer Umgebung ein in der Phase zeitverändertes Sendesignal. In der Empfangsphase erhält dann der Empfänger E ebenfalls ein in der Phase verändertes Signal. Eine positive zeitveränderliche Dopplerverschiebung tritt auf, solange sich die Antennenabtastung auf den Reflexpunkt zu bewegt.FIG. 2 shows in a block diagram the electrical connection of an exemplary embodiment according to FIG. 1. The transmitting and receiving antenna elements A are each connected to a phase-stable HF transmitter S during a time Δt and then to a receiver E during the time Δt. The continuous, rotational movement of the antennas, for example with the ROSAR principle, is electronically controlled by ten of the RF transmitter S from one antenna element A to the next. In this case, a reflection point to be imaged on the runway (not shown) or a point (not shown) in its vicinity receives a transmission signal which changes in time in phase. In the receiving phase, the receiver E then also receives a signal that has changed in phase. A positive time-varying Doppler shift occurs as long as the antenna scan moves towards the reflex point.
Sobald sich die Antennenabtastung vom Reflexpunkt weg bewegt, wird eine zeitveränderliche negative Dopplerverschiebung erzeugt. Die Aufprägung der Dopplerhisto- e bzw. der Phasenhistorie auf das ursprüngliche Sendesignal mit konstanter Frequenz ist, wie z.B. beim ROSAR-Standardverfahren bei Hubschraubern, für jede laterale Position eines Reflexpunktes - jedoch unter Einbeziehung der Fluggeschwindigkeit - berechnet.As soon as the antenna scan moves away from the reflex point, a time-varying negative Doppler shift is generated. The impression of the Doppler history or the phase history on the original transmission signal at a constant frequency is, e.g. in the ROSAR standard procedure for helicopters, for each lateral position of a reflex point - but taking the airspeed into account.
Wie beim Standardverfahren wird die Reflexion eines Reflexionspunktes, der ein Bildpunkt der abzubildenden Szene ist, durch eine in einem Korrelator K durchgeführte Kreuzkorrelation des empfangenen Signalgemisches mit dem Referenzsignal dieses Reflexionspunktes, welches aus dem Referenzsignalspeicher RS entnommen ist, ermittelt. Auch im hier vorliegenden Fall unterscheiden sich die einzelnen Refe- renzsignale - von Sonderfällen abgesehen - für einen Entfernungsring nur durch die Winkellage, so dass nicht für jeden Reflexionspunkt ein eigenes Referenzsignal abgespeichert und korreliert werden muß.As with the standard method, the reflection of a reflection point, which is an image point of the scene to be imaged, is determined by cross-correlation of the received signal mixture with the reference signal of this reflection point, which is taken from the reference signal memory RS, carried out in a correlator K. In the present case, too, the individual reference signals - apart from special cases - differ for a range ring only by the angular position, so that a separate reference signal does not have to be stored and correlated for each reflection point.
Im Gegensatz zum einem ROSAR-Radarsystem, bei dem der Hubschrauber als ru- hend angenommen wird, tritt aber bei dem hier vorgeschlagenen Radarsystem das Problem der schnellen Abstandsänderung durch die hohe Fluggeschwindigkeit auf, die eine Bildverzerrung bewirkt. Neben der Möglichkeit, das gesamte Bewegungsgeschehen zu modellieren und somit in alle Berechnungen insbesondere in die Bildentzerrung einbeziehen zu können, bietet sich aufgrund der elektrischen Abtastung eine extreme Verkürzung des gesamten Abtastzyklus an, so dass der Effekt der Abstand- sänderung zu einer vernachlässigenden Bildverzerrung führt. Dadurch wird eine rechenaufwendige Bildentzerrung eingespart.In contrast to a ROSAR radar system, in which the helicopter is assumed to be dormant, the problem with the radar system proposed here is that the distance changes quickly due to the high airspeed, which causes image distortion. In addition to the possibility of modeling the entire movement process and thus being able to include it in all calculations, in particular in the image equalization, the electrical scanning offers an extreme shortening of the entire scanning cycle, so that the effect of the distance change leads to negligible image distortion. This saves computational image correction.
Die Fig. 3 zeigt ein Ausführungsbeispiel für einen Verlauf von Sende- und Empfangs- Signalen mit ihren Intervallen "Senden" und "Empfangen". Auf der Abzisse ist der sich wiederholende zeitliche Verlauf der Ansteuerung benachbarter Antennenelemente dargestellt. Das erste Antennenelement sendet während der Zeit Δts den kurzen Sendeimpuls S1. In der daran anschließenden Zeitspanne Δte empfängt das erste Anntennenelement das Sendesignal El Auf der Ordinate ist einheitenlos die Ampli- tude des Sende- und Empfangssignals aufgetragen.FIG. 3 shows an exemplary embodiment for a course of transmit and receive signals with their "send" and "receive" intervals. The repeating chronological course of the activation of adjacent antenna elements is shown on the abscissa. The first antenna element transmits the short transmission pulse S1 during the time Δt s . In the subsequent time period .DELTA.t e , the first antenna element receives the transmission signal El. The ordinate plots the amplitude of the transmission and reception signal without units.
Weiterhin wird vorgeschlagen, dass eine Piloten-Sichtausstattung vorhanden ist, in der die gewonnenen Radar-Informationen eingeblendet werden können. So kann z.B ein virtuelles Cockpit vorhanden sein, in dem z.B. ein dreidimensionales Computer- bild der Umgebung abgebildet wird.It is also proposed that pilot visual equipment be available in which the radar information obtained can be displayed. For example, there can be a virtual cockpit in which e.g. a three-dimensional computer image of the surroundings is imaged.
Durch eine aktuelle Hinderniseinblendung in das virtuelle Cockpit ist eine wesentliche Steigerung der Effizienz computerorientierter Flugführung erzielbar. Das virtuelle Cockpit erfordert eine aktuelle Ortsinformation durch GPS. Wegen der notwendigen Positionsgenauigkeit wird hierfür das besser geeignete "Differential-GPS" vorgeschlagen. Falls die Notwendigkeit besteht, Positions- oder Hindernisdaten effizient zu übertragen, wird entweder ein HFA HF-Datenlink oder Mobilkommunikation über GSM- oder Satellitennetz vorgeschlagen. Der Einsatz der Mobilkommunikation ermöglicht eine beidseitige Kommunikation, d.h. Vollduplexbetrieb und Gruppen- Kommunikation. Der Vorteil der HF/VHF-Kommunikation liegt in der Unabhängigkeit on verfügbaren Infrastrukturen. Autarke Kommunikationsmöglichkeiten sind besonders bei militärischen Einsätzen in teilweise unbekannten Gebieten erforderlich.A current obstacle display in the virtual cockpit can significantly increase the efficiency of computer-oriented flight guidance. The virtual cockpit requires current location information through GPS. Because of the necessary position accuracy, the more suitable "differential GPS" is proposed for this. If there is a need to transmit position or obstacle data efficiently, either an HFA RF data link or mobile communication via GSM or satellite network is suggested. The use of mobile communication enables two-way communication, i.e. Full duplex operation and group communication. The advantage of HF / VHF communication is the independence of available infrastructures. Self-sufficient communication options are particularly necessary for military operations in partially unknown areas.
Fig. 5 zeigt ein weiteres Ausführungsbeispiel des erfindungsgemäßen Radarsystems. Dabei ist schematisch der Schnitt durch den Bug eines Flugkörpers gezeigt. Die Radarinformationen der Antennenelemente desjenigen Ausschnitts KA des Antennen- arrays an dem beispielhaft kreisförmigen Bug wird vorteilhaft nach dem ROSAR- Verfahren ausgewertet.5 shows a further exemplary embodiment of the radar system according to the invention. The section through the nose of a missile is shown schematically. The radar information of the antenna elements of that section KA of the antenna Arrays on the circular bow, for example, are advantageously evaluated using the ROSAR method.
Der sich an diesen Ausschnitt KA anschließende Ausschnitt LA des Antennenarrays wird vorteilhaft nach dem linearen SAR-Verfahren ausgewertet. Durch dieser vorteilhafte Kombination der beiden Auswerteverfahren ist mit dem erfindungsgemäßen Radarsystem eine Rundsicht möglich, ohne dass z.B. ein "Squint- Mode" erforderlich wäre, mit dem Verluste in der Auflösung bzw. ein erhöhter Signalverarbeitungsaufwand durch den schrägen Antennenblickwinkel verbunden wären.The section LA of the antenna array which adjoins this section KA is advantageously evaluated according to the linear SAR method. Through this advantageous combination of the two evaluation methods, a radar view is possible with the radar system according to the invention without, for example, a "squint mode" would be required, with which losses in the resolution or an increased signal processing outlay would be connected due to the oblique antenna viewing angle.
In Fig. 6 ist ein weiteres Ausführungsbeispiel des erfindungsgemäßen Radarsystems dargestellt. Dabei ist in schematischer Darstellung die Radarnase RN eines Flugkörpers in Seitenansicht dargestellt. Die Antennenelemente A sind entsprechend der Kontur K des Flugkörpers flächig angeordnet. Die Antennenelemente A sind dabei zu Antennenarrays zusammengefaßt, welche aus Gründen der Übersichtlichkeit nicht eingezeichnet sind.6 shows a further exemplary embodiment of the radar system according to the invention. The radar nose RN of a missile is shown in a schematic representation in a side view. The antenna elements A are arranged flat according to the contour K of the missile. The antenna elements A are combined to form antenna arrays, which are not shown for reasons of clarity.
Die dargestellte Anordnung der Antennenelemente A ist dabei lediglich beispielhaft. Selbstverständlich ist auch eine andere Anordnung der Antennenelemente A möglich. The arrangement of the antenna elements A shown is only an example. A different arrangement of the antenna elements A is of course also possible.

Claims

Patentansprüche claims
1. Radarsystem zur aktiven Hinderniswarnung und Abbildung der Erdoberfläche, das pulsfrequent oder im FM-CW-Bereich arbeitet und in Echtzeit im Online- Betrieb einsetzbar ist, umfassend eine Vielzahl von Antennenelemente zum1. Radar system for active obstacle warning and imaging of the earth's surface, which operates at pulse frequency or in the FM-CW range and can be used in real time in online operation, comprising a large number of antenna elements for
Senden und Empfangen von Radarsignalen, welche am Rumpf eines Flugkörpers angeordnet sind und welche zeitlich nacheinander ansteuerbar und abtastbar sind, wobei durch periodisches Senden und Empfangen der Antennenelemente eine synthetische Apertur erzeugt werden kann, dadurch gekennzeich- net, dass die Antennenelemente entlang der gekrümmten Flugkörperkontur amTransmitting and receiving radar signals, which are arranged on the fuselage of a missile and which can be controlled and scanned one after the other in time, wherein a periodic transmission and reception of the antenna elements can produce a synthetic aperture, characterized in that the antenna elements along the curved missile contour on
Flugkörper angebracht sind, wobei ein SAR-Prozessor vorhanden ist, der die von den Antennenelementen gewonnenen Informationen ausgewertet und als prozessierte Radarbilder an Bord des Flugkörpers in einem virtuellen Cockpit darstellt.Missiles are attached, a SAR processor being present, which evaluates the information obtained from the antenna elements and displays them as processed radar images on board the missile in a virtual cockpit.
2. Radarsystem nach Anspruch 1 , dadurch gekennzeichnet, dass die von einem vorgebbaren Ausschnitt der Antennenelemente erzeugte synthetische Apertur nach dem linearen SAR-Verfahren verarbeitet wird.2. Radar system according to claim 1, characterized in that the synthetic aperture generated by a predeterminable section of the antenna elements is processed according to the linear SAR method.
3. Radarsystem nach einem der Ansprüche 1 oder 2, dadurch gekennzeichnet, dass die von einem weiteren vorgebbaren Ausschnitt der Antennenelemente er- zeugte synthetische Apertur nach dem ROSAR-Verfahren verarbeitet wird.3. Radar system according to one of claims 1 or 2, characterized in that the synthetic aperture generated by a further predeterminable section of the antenna elements is processed according to the ROSAR method.
4. Radarsystem nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass die Zeit für einen Abtastzyklus so gewählt wird, dass trotz der Flugzeugbewegung keine Verzerrung des Bildes der abzubildenden Außenszene entsteht, was auch als Verschmierung von Bildpunkten bezeichnet wird.4. Radar system according to one of the preceding claims, characterized in that the time for a scanning cycle is selected such that despite the aircraft movement there is no distortion of the image of the exterior scene to be imaged, which is also referred to as smearing of pixels.
5. Radarsystem nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass die Berechnung von Referenzsignalen für wichtige Bildpunkte der Außenszene gemäß dem bekannten ROSAR-Verfahren erfolgt, jedoch unter zusätzlicher Berücksichtigung der Fluggeschwindigkeit.5. Radar system according to one of the preceding claims, characterized in that the calculation of reference signals for important pixels the outside scene takes place in accordance with the known ROSAR process, but with additional consideration of the flight speed.
6. Radarsystem nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass zur Bildung eines dreidimensionalen Radarsystems die zu An- tennenarrays zusammengefaßten Antennenelemente entsprechend räumlich angeordnet bzw. positioniert sind.6. Radar system according to one of the preceding claims, characterized in that in order to form a three-dimensional radar system, the antenna elements combined into antenna arrays are arranged or positioned correspondingly in space.
7. Radarsystem nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass die gewonnenen Informationen als dreidimensionales Computer- Bild der Umgebung in dem virtuellen Cockpit darstellbar sind.7. Radar system according to one of the preceding claims, characterized in that the information obtained can be represented as a three-dimensional computer image of the environment in the virtual cockpit.
8. Radarsystem nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass zur Effizienzsteigerung einer computerorientierten Flugführung die aktuellen Hindemisse in das virtuelle Cockpit einblendbar sind.8. Radar system according to one of the preceding claims, characterized in that in order to increase the efficiency of a computer-oriented flight guidance, the current obstacles can be faded into the virtual cockpit.
9. Radarsystem nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass dem virtuellen Cockpit die aktuelle Ortsinformation durch GPS oder Differential-GPS eingebbar ist.9. Radar system according to one of the preceding claims, characterized in that the virtual cockpit, the current location information can be entered by GPS or differential GPS.
10. Radarsystem nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass ein HF/VHF-Datenlink vorhanden ist, mit dem ein effiziente Übertragung der Positions- und Hindernisdaten mittels Mobilkommunikation über GSM oder Satellitennetz möglich ist.10. Radar system according to one of the preceding claims, characterized in that an HF / VHF data link is present, with which an efficient transmission of the position and obstacle data is possible by means of mobile communication via GSM or satellite network.
11. Radarsystem nach einem der vorangehenden Ansprüche zur Verwendung auf Kampf- und/oder Aufklärungsdrohnen. 11. Radar system according to one of the preceding claims for use on combat and / or reconnaissance drones.
EP02732400A 2001-04-26 2002-04-24 Radar system for obstacle warning and imaging of the surface of the earth Withdrawn EP1386179A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10120536A DE10120536C2 (en) 2001-04-26 2001-04-26 Radar system for active obstacle warning and imaging of the earth's surface
DE10120536 2001-04-26
PCT/DE2002/001496 WO2002088771A1 (en) 2001-04-26 2002-04-24 Radar system for obstacle warning and imaging of the surface of the earth

Publications (1)

Publication Number Publication Date
EP1386179A1 true EP1386179A1 (en) 2004-02-04

Family

ID=7682856

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02732400A Withdrawn EP1386179A1 (en) 2001-04-26 2002-04-24 Radar system for obstacle warning and imaging of the surface of the earth

Country Status (5)

Country Link
US (1) US7023375B2 (en)
EP (1) EP1386179A1 (en)
JP (1) JP2004532412A (en)
DE (1) DE10120536C2 (en)
WO (1) WO2002088771A1 (en)

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10306922B4 (en) * 2003-02-19 2006-04-13 Eads Deutschland Gmbh Device for monitoring an airport area
DE10335216B4 (en) * 2003-08-01 2005-07-14 Eads Deutschland Gmbh In the area of an outer surface of an aircraft arranged phased array antenna
US8130222B1 (en) 2004-10-19 2012-03-06 Rockwell Collins Simulation And Training Solutions Llc System and method for resolving visual priority among coincident primitives
DE102004061486B4 (en) * 2004-12-21 2007-04-05 Eads Deutschland Gmbh A method for signal data processing of an aircraft-borne synthetic aperture radar and apparatus therefor
ATE407368T1 (en) * 2005-07-23 2008-09-15 Deutsch Zentr Luft & Raumfahrt SYNTHETIC APERTURE RADAR (SAR) SYSTEM
JP4769596B2 (en) * 2006-02-27 2011-09-07 株式会社デンソーアイティーラボラトリ Electronic scanning radar equipment
DE102007003615B4 (en) 2007-01-18 2011-03-10 Eads Deutschland Gmbh Method and device for recognizing objects
US8049644B1 (en) 2007-04-17 2011-11-01 Rcokwell Collins, Inc. Method for TAWS depiction on SVS perspective displays
US7609200B1 (en) * 2007-05-29 2009-10-27 Rockwell Collins, Inc. Radar derived perspective display system
US9733349B1 (en) 2007-09-06 2017-08-15 Rockwell Collins, Inc. System for and method of radar data processing for low visibility landing applications
US9354633B1 (en) 2008-10-31 2016-05-31 Rockwell Collins, Inc. System and method for ground navigation
US8977491B1 (en) 2007-09-06 2015-03-10 Rockwell Collins, Inc. System and method for verifying displayed terrain information
US9939526B2 (en) 2007-09-06 2018-04-10 Rockwell Collins, Inc. Display system and method using weather radar sensing
US8466874B1 (en) 2009-02-10 2013-06-18 Rockwell Collins, Inc. System and method for graphical rendering of point primitives
US9118112B1 (en) * 2013-03-14 2015-08-25 Rockwell Collins, Inc. Multi-sensor system and method for vehicles
US9262932B1 (en) 2013-04-05 2016-02-16 Rockwell Collins, Inc. Extended runway centerline systems and methods
US10928510B1 (en) 2014-09-10 2021-02-23 Rockwell Collins, Inc. System for and method of image processing for low visibility landing applications
US10705201B1 (en) 2015-08-31 2020-07-07 Rockwell Collins, Inc. Radar beam sharpening system and method
US10228460B1 (en) 2016-05-26 2019-03-12 Rockwell Collins, Inc. Weather radar enabled low visibility operation system and method
US10353068B1 (en) 2016-07-28 2019-07-16 Rockwell Collins, Inc. Weather radar enabled offshore operation system and method
CN115639553B (en) * 2022-12-15 2023-03-21 北京航空航天大学 Optical SAR integrated satellite detection system based on photoelectric path coupling

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3922086C1 (en) * 1989-07-05 1990-10-18 Messerschmitt-Boelkow-Blohm Gmbh, 8012 Ottobrunn, De
DE4007612C1 (en) * 1990-03-09 1991-05-16 Deutsche Forschungsanstalt Fuer Luft- Und Raumfahrt Ev, 5300 Bonn, De
DE4323511C1 (en) * 1993-07-14 1995-01-26 Deutsche Aerospace Radar device for obstacle warning
DE4328573C2 (en) * 1993-08-25 1995-12-14 Daimler Benz Aerospace Ag All-weather vision system for helicopters
GB2317086A (en) 1996-09-05 1998-03-11 Secr Defence Virtual reality system
SE507919C2 (en) * 1997-06-18 1998-07-27 Foersvarets Forskningsanstalt Ways to produce a three-dimensional image of a land area using a SAR radar
DE19731262A1 (en) * 1997-07-21 1999-02-11 Deutsch Zentr Luft & Raumfahrt Aircraft avionic system using onboard radar
JP3586569B2 (en) * 1998-07-31 2004-11-10 日本電気株式会社 Image synthesizing method using a plurality of reflected radar waves and image radar apparatus mounted on an aircraft using the same
US6054947A (en) * 1998-08-28 2000-04-25 Kosowsky; Lester H. Helicopter rotorblade radar system
US6885340B2 (en) * 2000-02-29 2005-04-26 Rannoch Corporation Correlation of flight track data with other data sources
DE19945791C1 (en) * 1999-09-24 2001-05-17 Daimler Chrysler Ag Helicopter-borne radar system
DE10015164A1 (en) * 2000-03-27 2001-10-11 Helmut Klausing ROSAR communication method for obstacle detection in helicopter, involves merging heliradar laser-radar sensor data with registered data of on-board-intrinsic database for display of flight path and landing location
US6795590B1 (en) * 2000-09-22 2004-09-21 Hrl Laboratories, Llc SAR and FLIR image registration method

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO02088771A1 *

Also Published As

Publication number Publication date
US20040201513A1 (en) 2004-10-14
JP2004532412A (en) 2004-10-21
US7023375B2 (en) 2006-04-04
DE10120536C2 (en) 2003-12-24
WO2002088771A1 (en) 2002-11-07
DE10120536A1 (en) 2002-11-21

Similar Documents

Publication Publication Date Title
EP1386179A1 (en) Radar system for obstacle warning and imaging of the surface of the earth
DE4244001A1 (en)
EP0550073B1 (en) System for locating multiple objects and obstacles and for detecting and determining the rolling state of moving objects, such as aircraft, ground vehicles, etc.
EP0634669A1 (en) Method for classifying an object and application thereof
EP1381879B1 (en) Method for recognizing and identifying objects
EP1746437B1 (en) Synthetic Aperture Radar System (SAR)
EP0445795B1 (en) Forward looking radar
DE4007612C1 (en)
EP1674884B1 (en) Method of signal processing in an airborne radar with synthetic aperture and device therefor
WO2004075139A1 (en) System for monitoring airport areas
EP1515159A1 (en) Method for reducing the doppler centroid for coherent pulsed radar system
DE10015164A1 (en) ROSAR communication method for obstacle detection in helicopter, involves merging heliradar laser-radar sensor data with registered data of on-board-intrinsic database for display of flight path and landing location
WO2010034297A1 (en) Aircraft-based detection system
DE19818426C2 (en) Remote reconnaissance and targeting procedures
DE69826860T2 (en) METHOD AND DEVICE FOR OBTAINING VISION THROUGH VIRTUAL PICTURES
DE102010035601B4 (en) Method and apparatus for radar imaging a scene in anticipation of a moving platform
DE102012006784B4 (en) Device and method for locating radio signals by means of Doppler effect on board flying platforms
EP3564708B1 (en) Synthetic aperture radar method for remote sensing of the earth´s surface and synthetic aperture radar device
DE4210823A1 (en) Microwave aircraft landing procedure for poor visibility conditions - using EM beam provided by satellite and reflected from ground surface in direction of approaching aircraft
WO1999005541A1 (en) Avionic system intended for use in aircrafts and involving use of an on-board radar equipment
DE19731262A1 (en) Aircraft avionic system using onboard radar
EP0690316A1 (en) Low visibility imaging radar system
DE19731263A1 (en) Aircraft avionic system using onboard radar
DE19731169A1 (en) Aircraft avionic system using onboard radar
DE102018120383A1 (en) Radar system with a synthetic antenna aperture

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

17P Request for examination filed

Effective date: 20030814

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

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: 20071031