DE2111937A1 - Three-dimensional target display arrangement for radar systems - Google Patents

Description

Dip3 .-! Ng. Eepn Prinz , ·, _{Mä iq71}

Dr: Gertrud Hauser βοοο MDnchan 6o, «v.warz iyn

... Gottfried Leiser ^Ern5ber ° ^a "" ⁹

Patent Attorneys 2111937

Telegrams! labyrinth munich

Telephone: 83 15 10 Postal checking account: Munich 117078

Our reference: P 1204

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FLESSEY HAID) EL UICD INVESTMENTS AG
Gartenstrasse 2, 6300 Zug / Switzerland

Three-dimensional target display arrangement for Ea da rays te ms

The invention relates to radar systems, in particular on air surveillance radar systems.

With the known Rurdsicht display systems (PPI display systems), which are used in primary surveillance radars, air traffic is over a certain circular area of the earth's surface. There is no information from the radar device itself with respect to the altitude of the aircraft in the detection range of the radar device.

In some cases, elevation radars can be used to provide the elevation information, and that information can be displayed so that the height information is displayed by deflecting in the vertical direction on the display screen is expressed proportional to altitude, along with a left-to-right deflection, which is proportional to the distance.

In surveillance radar systems, it is also known to use a use polar or cartesian circular vision display device, in which the altitude information as well as an aircraft

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identifier in the form of alpha-numeric characters in the Representation can be inserted next to the information of the destination. The altitude information is provided by the aircraft itself determined, for example by range finders, and then to the radar station for display purposes transmitted on the all-round viewing device. Combinations the above solutions are also possible.

According to the invention contains a three-dimensional target display arrangement with a panoramic display device with a screen a device for tilting the depicted floor life of the panoramic view the screen to a desired angle of inclination and a device that sees a representation on the round visible display of the3 vertical distances3 of a target from the ground plane supplies.

The invention is particularly suitable for display in air surveillance radar systems in which the height of the Aircraft above ground level on the display screen can be displayed, for example, by the creation of substantially vertical bars that are between the target and the ground plane extend, being the length of the dash is an indication of the aircraft's altitude above ground level. Optionally or additionally you can also Calibration marks at different heights between the target shown on the screen and the ground level in vertical orientation with the target shown, so that the determination of the height of the Aircraft simply by counting the number of ele brands is facilitated.

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The display system according to the invention can therefore be used by the operator from a radar device simultaneously provides information on distance, lateral direction and altitude of an aircraft in the monitored space, the altitude information preferably being transmitted from the aircraft and identified with the individual ZMen that are on the display screen of the radar system.

It should be noted that targets for which no altitude information is available on the display screen so ass, ala whether they are at the height of the ground level found. This can be the case for tall buildings or the like near the radar station. Planes, for which no altitude information is received, or aircraft that are outside of the system selected, predetermined height range are, however, appear on the display as moving target points, since there is no vertical deflection at the location of this target height to indicate its height.

The Dars te 11 ungs system according to the invention results in a Real-time display, and although the tilting of the ground plane results in a normally circular one If the representation is deformed to an elliptical representation, it should be noted here that the empty areas between the ellipse and the boundary of the usually circular display screen by suitable adaptation of the system are included in the entire display area can be.

A further development of the invention consists in that the floor plane is rotated about its vertical central axis, so that the height separation of targets that are vertically one above the other on the display screen is facilitated, which can have the consequence that the height lines and / or the height calibration marks, which are assigned to these goals,

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overlap each other.

A special embodiment of the invention is that in addition to the three-dimensional representation, a separate height display is provided in which the target heights information are transferred from the three-dimensional representation to the separate representation, so that on the separate display vertical deflections are obtained which indicate the altitude, but with the position of these vertical distractions does not provide a true indication of the target range.

The invention is illustrated by way of example with reference to the drawing described. Show in it:

1 shows a diagram to explain the invention underlying principle,

2 shows a geometric representation to explain the Method of generating the panorama and elevation display in an air surveillance radar system;

3 is a schematic view of a radar display device showing two aircraft at different heights shows within the detection range of the radar device,

Fig * 4 timing diagrams to illustrate the generation of the Course of the signals for the vertical deflection to display the height,

5 shows the block diagram of a circuit arrangement for generation the height deflection signals of Figure 4,

6 shows the block diagram of a circuit arrangement for Generation of the height display video signal of the representation,

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Pig.7 the block diagram of an arrangement for generation of height gauges in the target height display arrangement,

Pig.8 a control arrangement for controlling the inclination the ground level of the round sees display device and the appropriate setting of the height deflection according to the selected angle of inclination and

Pig.9 the block diagram of a circuit arrangement for Completion of the three-dimensional representation in the areas between the perimeter of the elliptical floor plane and the edge of the usual round radar display noise,

Pig.1 of the drawing shows how a screen display for an air surveillance radar system according to the invention is a View corresponds to that of an observer 0 in space from an intermediate angle between the vertical position, that of the real top view (round sees the division) and the horizontal position. In Pig.1 is the Earth's surface is shown at E, and the segment AB represents the Y-axis of the elliptical area under consideration which has a larger X-axis (not shown). As can be seen, this gives a three-dimensional view for the observer O a simultaneous perception of the height, the lateral direction and the distance of each plug tool within his field of vision. With the invention, a three-dimensional radar display arrangement is created, which supplies the corresponding information for a plug-in tool in the detection area of the radar device.

Pig.2 shows a diagram similar to that of Pig.1, in which is a plug stuff at location K, the length of the route KL being proportional to the vertical height of the

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Aircraft is above the effective ground level GP. the Distance and the lateral direction of the aircraft herds indicated by point L on the elliptical sod plane.

So that this view would be seen on a display screen, the screen would have to be inserted between the ground plane GP and the observer 0, for example in the position MN, which is at right angles to the normal line of sight of the observer. The image that then appears is the same as that of a shira in the FQ position, except for a scale factor, and it is obviously just a projection of the original on this plane. This projection can be generated on the display screen in a very simple manner. The inclination of the ground plane GP can be generated by reducing the vertical deflection of the usual polar roundsiclit display (PPI display) until the desired viewing angle is achieved, making an elliptical one Shape is obtained. As can be seen immediately, the amplitude of this vertical deflection has the value ⁿ 1 "for the true round view representation, and it changes with the value cos θ (where θ is the angle of inclination against the vertical) until the value" O " for θ = 90 ° is achieved, which corresponds to a real side view in the normal line of sight. This can be achieved that the vertical deflection signal is fed to the usual deflection amplifier of the panoramic display device via a cosine potentiometer, so that the rotation of the potentiometer corresponds to the angle of inclination Correspondingly, the projected length of the contour line KL in the real panoramic view has the value "O", and it changes with the value sin Q until it is θ = 90 ° The value "1" is reached. This is achieved by feeding an additional deflection signal to the usual deflection amplifiers via a sine potentiometer, the setting of which

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spindle with that of the aforementioned cosine potentiometer is coupled, ensuring the correct proportions of the image at all angles of inclination of the ground plane GP to be obtained

.3 schematically shows a screen with a representation which corresponds to the view of FIG. There are two planes and their distances and lateral directions are derived directly from the range rings RR1, RR2, RR3 and recognizable from the lateral direction markings BM; likewise their heights are given by the lengths of the lines KL and PQ to recognize. Calibration marks can be provided along the lines KL and PQ. As can be seen, it is Representation elliptical, but the areas RK1 and RK2 be completed in a manner to be described later.

The aforementioned additional deflection signal for achieving the aircraft altitude deflection consists of a triangular one Height deflection signal TV /, which is shown in Fig.4.

At this point it is useful to refer to Fig.5, which is the block diagram of an arrangement shows, with which the height deflection signal TW shown in Figure 4 can be generated. The signal TW can be due to a Altitude information is generated, which is either transmitted by the aircraft itself or by an altitude radar station After suitable processing, this height information is fed to an amplifier A1, its output signal is input to a further amplifier A2 which is designed so that it can be selected according to the desired height range via height range selection connections S1, S2, S3 can be set. For example, the elevation ranges can be Q-8,000 feet, 0-16,000 feet, and 0-32 Foot can be selected · It can also be provided that the ground level is raised to a predetermined peak height,

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so that plug-stuffs that fly below this summit height, and thus altitude signals whose amplitude corresponds to an altitude below this peak altitude are discarded. For the purpose of rejecting the height pulses emitted by the amplifier A2 which correspond to heights outside the selected height range, the output pulses of the amplifier A2 are the inputs of two blocking circuits 11 and 12, those of the upper limit and the lower limit, respectively Limit of a selected height range are assigned and then deliver output signals when the amplitude the input pulses in a predetermined amplitude range which corresponds to the required height range. These output signals become an AND gate G1 supplied. The AND gate G1 is also shown in Depending on the application of a primary video signal or target echo signal, such as the VS signal from Pig.4 the input line PV controlled. After amplification in an amplifier A3, this signal goes through a signal delay arrangement D1, which creates a delay in order for that from amplifiers A1 and A2 and the blocking circuits 11 and 12 generated at the other input of the AND gate G1 Delay is taken into account. Another input signal for the Ünd gate G1 is via the line IX supplied when the plug stuff is in the required range of the radar system. Otherwise a blocking signal is applied to this line, which prevents the opening of the Ünd gate G1, so that this no Can emit output signal «

The output signal of the amplifier A2, which the! Aircraft altitude represents, two analog switches AN1 and AN2 fed by an assigned monostable tilting * circuit M0N1 or M0N2 can be controlled. If the AND gate G1 is opened, its output signal triggers the

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Bjonostable multivibrator M0N1 off, whereby the analog switch AN1 is opened so that it transmits a positive pulse P1 (Fig. 4) representing the aircraft height to a buffer amplifier 3F1, whose amplified output signal is fed to an integrating amplifier AI. At the end of the quas! Stable period the monostable multivibrator ΜΟΝΊ (e.g. 6 us) it returns to the idle state, which triggers the monostable multivibrator M0N2 so that it opens the analog switch AN2. The positive output pulse of the analog switch AN2 is fed to a buffer amplifier BF2, which inverts its input signal, so that a negative output pulse P2 (FIG. 4) is generated for the duration of the quasi-stable period of the monostable multivibrator M0N2. This negative pulse P2 is fed to the integrating amplifier AI following the pulse P1, and the integrating amplifier accordingly generates a triangular output signal, which is shown at TW in FIG. The duration of each of the successive pulses that are integrated to generate the triangular signal TW can be six microseconds, because this pulse duration is a reasonable compromise between the maximum achievable altitude deflection, which is determined by the writing speed of the display device ia%, and the resolution between two Flugzettgen in the same side direction, which is determined by the speed of propagation. The total function value of 12 microseconds gives a resolution of about 1 mile and a maximum elevation deflection of 20 ^ of the screen diameter in a particular case. This signal TW forms the height deflection signal for the height display in the three-dimensional representation of the system.

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The & rad, in which this height deflection signal appears on the presentation sohirra, determines the brightness of a figure indicating the vehicle height, which is practically a vertical line, since the leading edge and the trailing edge of the height deflection signal almost coincide in the representation. 6 shows a circuit arrangement for a selection and generation of the video height signals. The output signal of the AND gate G1 of FIG. 6 is fed to the inputs of three monostable multivibrators MONA, MONB and MONO via a trigger line TL. The raonostable multivibrators have control lines CLA, CLB and CLC, which are optionally energized to trigger the monostable multivibrators according to the height video signals to be displayed. If the entire triangular height deflection signal TW of FIG. 4 is to be displayed, the monostable multivibrator MONA is triggered, while the monostable multivibrator MONB is triggered for a partial display of the height deflection signal. If, on the other hand, only one marking for the height zero is required on the display, the monostable multivibrator MONO is triggered. The height deflection signal coming from the integrating amplifier AI (Fig.5) is transmitted over the line XP and entered in an analog switch AN6, which is opened so that the height signal can reach an amplifier A4 when a corresponding output signal from an OR gate G2 after the Triggering of the monostable multivibrator MONA or MONB is issued. Thus, the height deflection signal goes in whole or in part to the amplifier A4, depending on which of the monostable multivibrators MONA and MONB has been actuated. The output signal from amplifier A4 is fed to a further amplifier A5 via a gain control potentiometer GC1. The video height signal is derived from the output of amplifier A5.

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If only a zero height mark is needed, the monostable multivibrator MONO is triggered, and that The output of this circuit is amplified by the amplifier A6 before passing through a gain control potentiometer GG2 enters amplifier A5. In this case, the output of the amplifier A5 consists of one Pulse with a very small amplitude compared to the pulse height of the signal IW. This makes a very short vertical Line or practically a point is generated on the display.

The Au3gangssignal of the amplifier A5 is the round-view display device applied to the conventional Y-deflection passage, so that a vertical deflection is generated while the display screen during operation of the radar apparatus UUD radial angle is scanned for.

Pig.8 shows a control arrangement for the inclination of the Ground level. The usual Y-main deflection voltage of the usual all-round display circuit is used to tilt the floor level a potentiometer PT is supplied via the line YP, and a suitable fraction of this input voltage is after amplification in a buffer amplifier the Y-deflection system of the panoramic display device supplied. This reduction the Y deflection voltage creates the toggle. There the amplitude of the altitude map signal corresponding to the The angle of inclination also has to be reduced to scale, is that supplied by the amplifier A5 in FIG Height deflection signal sent via a potentiometer PK, before it reaches the Y auxiliary deflection input of the panoramic display device after amplification in a buffer amplifier. As can be seen without further ado, by actuation the switches SW1, SW2, SW3 and SW4 can be achieved that instead of the three-dimensional display, either a real panoramic display or a side view display is obtained if so desired.

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4Ji

In addition to the altitude deflection signal, altitude calibration marks can be superimposed on the altitude deflection signal to provide an indication of the aircraft altitude by one or more short, vertically superimposed bars, each mark corresponding, for example, to an altitude level of 2000 feet. These height mark signals are entered into the Y deflection input of the panoramic display device during the rising slope of the height deflection signal TW and for this purpose are fed from the line HM (I ¹ Ig.6) via a gain control potentiometer GC3 to the input of the amplifier A5 derived from the height marker generator shown in Bg7.

That derived from the integrating amplifier AI in Flg.5 Elevation deflection signal is transmitted over the HSL line and after amplification in a) buffer amplifier BF5, the inputs of several (for example 16) comparison circuits COM are jointly supplied. The comparison circuits COM are divided into two groups GOMA and COMB. A constant DC voltage generated by a circuit with a constant current source SC and a reference diode KD is derived, is sent via amplifiers A10 and A11 to a Resistance chain created, which is represented by the block RC. Taps along the resistance chain RC are connected to the inputs of the comparison circuits, and these have the task of reducing the voltage at altitude to compare the voltage drops across the chain of resistors and to generate a pulse-shaped digital output signal, which corresponds to the analog height deflection signal on the input line HSL · The digital output signal contains a series of positive pulses via delay circuits D2, D3, D4 and a gate circuit G10 to a monostable multivibrator M0N3 are faded out The monostable multivibrator M0N3 is triggered by every pulse in the pulse train,

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and the number of pulses depends on the amplitude of the altitude deflection signal applied to the line HSL. the Output pulses of the monostable multivibrator M0N3 are fed to an amplifier A12. So for relief the reading of the aircraft altitude by an operator along coarse and fine grains at intervals a number of calibration marks can be provided, is the measure in the illustrated embodiment taken that every second mark or every fifth mark is a coarse mark compared to the others Brands is thick. This is achieved in that every second or every fifth pulse in the output pulse train the comparison circuits GOM via a frequency divider DIV2 with the division factor 2 or a frequency divider DIV5 with the division factor 5 triggers a monostable multivibrator M0N4, depending on which of these Frequency divider is connected to the monostable multivibrator M0N4 by a switching arrangement SWD. The output of the one-shot multivibrator M0N4 is also fed to the amplifier A12.

The zero level mark is generated by a monostable multivibrator M0N5, which has the output signal at its input of the AND gate G1 of FIG. 5 so that they coincides in time with the beginning of the height deflection signal TW. The selection of the coarse height marks, the fine height marks and the zero height mark is made by appropriate actuation of switches CS and FS.

The output pulse of the amplifier A12 is fed to the amplifier A5 of Figure 6, the output signal as bereita has been described, is supplied to the tilt angle control arrangement of Figure 8 before it is input to the conventional Y-deflection path of the conventional round-view display device s.

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As can be seen from the illustration in FIG. 3, the ground plane is elliptical, so that the areas RK1 and RK2 remain unused when the radar system is in operation In this arrangement, the X and Y clock signals supplied by the block Z1 are fed to the rotation control arrangement 7.2 , the Y output signal of which is transmitted via the inclination angle control circuit AT1 to the Y range change amplifier YRCA. The X output 3 signal of the rotation control arrangement Z2 is fed directly to an X range change amplifier XRGA. The amplifiers XRCA and YRCA provide the X or. Y main output signals. The height deflection signal for the height deflection generation HS is transmitted via the inclination angle control switch AT2, whereby a Y auxiliary output signal is created for the panoramic display device.

From the above description it can be seen that the display arrangement according to the invention is isometric results in three-dimensional representation on the display screen, but can optionally also be a real perspective three-dimensional view can be obtained, with the removal rings, such as rings RR1, RR2 and RR3 in FIG. 3 are no longer exactly elliptical and also the lengths of the vertical ones representing the height signals Strokes decrease in size with increasing distance from the aircraft. Furthermore, the display arrangement is according to of the invention in connection with an air surveillance radar device has been described, but the described representations can also be ordered, for example, in the Mnrine apply to the depth of goals under the View sea level. This is done by reversing the height deflection signals, whereby depth deflection signals are obtained,

Claims 109840/1222

Claims (9)

Sponsorship claims Three-dimensional target display arrangement with a Rundaicht display device (PPI device) with a screen, characterized by a device for tilting the illustrated bottom plane of the round looks at representation the screen to a desired angle of inclination and by a device, which on the round view display a visible display of the vertical distance of a Target from ground level. 2. Three-dimensional target display arrangement according to claim 1, characterized by a device which is on the round ht display creates a vertical line that represents the indicates the vertical distance of a displayed target from the ground plane « 3. Three-dimensional target display arrangement according to claim 2, characterized by a device for generating a Number of height calibration marks depending on the Amplitude of a signal for generating the vertical line and for displaying the lift calibration marks the round looks representation along the vertical line. 4 «three-dimensional target display arrangement according to claim 2, characterized in that the length of the vertical bar indicates the altitude of an aircraft represented as a target on the screen and that the line is generated thereby, that to the Y-deflection circuit of the panoramic display device a signal supplied by an altitude video circuit is applied 5. Three-dimensional target display arrangement according to Anspru <'- characterized in that the height of the video chaos 109840/1222 supplied signal by a tilt angle control circuit is changed, which depends on the amplitude of the signal from the angle of inclination of the ground plane of the panoramic view changes « 6. Three-dimensional target display arrangement according to claim 3, characterized in that for generating the height calibration marks the signal for the generation of the vertical line is fed to a calibration mark generation circuit which contains comparison circuits which the amplitude of the signal with Compare reference values and a digital output signal supply, which consists of a number of pulses, which depends on the amplitude of the signal, and that this Pulses to the Y-deflection system of the panoramic display device are supplied in a suitable temporal relationship to the signal for generating the vertical line so that that a row of rakes is created along the vertical line. 7 three-dimensional target display arrangement according to claim 1, characterized in that the device for tilting the ground level contains a potentiometer, which is in the input circuit of the Y-deflection system of the all-round view display device is. 8. Three-dimensional target display arrangement according to claim 4, characterized in that the height video circuit is a triangular Height deflection signal is supplied, which is supplied by a height deflection generator, the height information receives via the aircraft displayed as targets on the screen 109840/1222 • 9 three-dimensional target display arrangement according to claim 8, characterized in that the height nable nkgeneisfcor blocking circuits contains which discard altitude information related to aircraft that are outside the Range of the radar device. Three-dimensional target display arrangement according to claim 9 or 9 »characterized in that the height deflection generator Contains blocking circuits which discard height information that relates to plug-in items that are outside a selected altitude range « 11. Three-dimensional target display arrangement according to claim 10, characterized in that the height range has a lower limit which is above the ground level " 12. Three-dimensional target display arrangement according to claim 4> characterized in that the height video circuit contains a number of circuits which can be selectively actuated so that the triangular height deflection signal is used as a video output signal in accordance with the level of brightness of the height display required in the display, in whole or in part. 13. Three-dimensional target display arrangement according to claim 12, characterized in that one of the circuits is adapted to display a short zero height mark causes which corresponds to the beginning of the triangular height deflection signal. 14. Three-dimensional target display arrangement according to one of the preceding claims, characterized by a device for expanding the area of the display in the! -direction 109840/1222 of the screen in such a way that the usual circular screen regardless of the tilting of the ground plane is fully exploited. 15. Three-dimensional target display arrangement according to a of the preceding claims, characterized by a device for rotating the floor plane about its vertical one Central axis for changing the angular position of targets on the screen. 9 6 ^ 0/122 / Blank page