JPH05172937A - Flying object monitoring device - Google Patents

Abstract

PURPOSE:To obtain a flying object monitoring device when can measure the altitude of a flying object with high accuracy without relying on an airborne transponder. CONSTITUTION:By forming fan-shaped beam surfaces intersecting each other at right angles and respectively oscillating the surfaces in orthogonal directions, slant ranges are respectively found from a time difference between transmitted pulse signals and the reflected pulse signals of the transmitted pulse signals from a target flying object at the moment the reflected pulse signals are received and, in addition, the deviated angle of each antenna beam is found at the same moment. Then the altitude and ground range of the target flying object is calculated by respectively assuming circular arcs having radii equal to slant ranges on the beam surfaces of a first and second antennas 1 and 2 based on the information and finding the intersection of both arcs. The calculated height and ground range are displayed on a display 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flying body monitoring apparatus capable of highly accurately measuring the altitude of an object flying in space such as an aircraft.

[0002]

2. Description of the Related Art Conventionally, when an aircraft is monitored from a control tower, a mode C of SSR (secondary surveillance radar) is used to send an inquiry signal to a target aircraft and receive a response signal from a transponder onboard the aircraft. And obtains altitude information measured on the aircraft side.

However, the altitude information measured on the aircraft side is converted from atmospheric pressure information, and the minimum unit is 1
The accuracy is low at around 00 feet. Further, since it depends on the on-board transponder, it is not possible to deal with a transponder failure or a machine without a transponder.

[0004]

As described above, conventionally, the altitude information is obtained from the atmospheric pressure-altitude conversion information on board the aircraft by using the transponder response signal mounted on the flying vehicle in the mode C of the SSR. Therefore, the accuracy is low, and it is not possible to deal with a transponder failure or a machine without a transponder.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a flying object monitoring apparatus capable of highly accurately measuring the altitude of a flying object without depending on an onboard transponder.

[0006]

In order to achieve the above object, a flying object monitoring apparatus according to the present invention includes first and second antennas each forming a beam having a substantially narrow width, and the first and second antennas. A beam scanning controller that scans the beams of the second antenna in directions orthogonal to each other to form a fan-shaped beam surface, and swings each beam surface in directions orthogonal to each other, and a pulse through the first and second antennas. Emits a signal,
Pulse transmission / reception means for receiving and detecting the reflected pulse signal from the target flying object, and the slant range is obtained from the time difference between the reflected pulse signal obtained from the reception outputs of the first and second antennas with respect to the transmitted pulse signal by this means, and Obtain each antenna beam deviation angle at the time of reception, and based on these information, assume an arc with the slant range as the radius on each beam surface of the first and second antennas, and find the intersection point between them. An information processing apparatus that obtains the height and the ground range of the target flying object from this intersection, and a display that displays the height and the ground range obtained by this information processing apparatus are configured.

[0007]

In the flying object monitoring apparatus having the above-described structure, the fan-shaped beam surfaces orthogonal to each other are formed, the beams are swung in the directions orthogonal to each other, and the reflection pulse signal from the target flying object with respect to the transmission pulse signal is received and detected. The slant range is calculated from the time difference between the pulse signal and the transmission pulse signal, and at the same time the antenna beam deviation angle at the time of reception is calculated. Based on this information, the beam planes of the first and second antennas are respectively calculated. The height of the target flying object and the ground range are calculated and displayed on the display by assuming an arc having a slant range as a radius and determining the intersection of the two.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows the structure of a flying body (here, an aircraft) monitoring apparatus according to the present invention. In FIG. 1, reference numerals 1 and 2 denote beam scanning antennas, each of which is capable of forming a fan beam having a narrow width in the scanning direction or equivalently narrowing the beam width by a monopulse pattern. However, since the aircraft moves at high speed, high-speed scanning is required, and an electronic scanning antenna is suitable for this purpose.

The antennas 1 and 2 are arranged close to each other, and the scanning of the antenna beam is controlled by a beam scanning controller. The beam scanning control device 3 scans the beams in directions orthogonal to each other to form fan-shaped beam surfaces BM1 and BM2.
, The beam surfaces BM1 and BM2 are swung in directions orthogonal to each other.

Transmitters 4 and 5 are provided for the antennas 1 and 2, respectively, and pulse signals emitted from the transmitters 4 and 5 at predetermined intervals are transmitted via the transmission / reception switchers 6 and 7 to the antennas 1 and 2. Emitted from. Further, the reception signals of the antennas 1 and 2 are supplied to the monopulse receivers 8 and 9 via the transmission / reception switchers 6 and 7 in the case of a monopulse pattern.

The monopulse receivers 8 and 9 detect reflected pulse signals from the aircraft from the antenna reception signals. The reflected pulse signal detected by each of the receivers 8 and 9 is supplied to the information processing device 10.

The information processing apparatus 10 is further supplied with beam directivity angle information from the beam scanning control apparatus 3 and pulse transmission timing information from each of the transmitters 4 and 5. The information processing device 10 controls the transmitters 4, 5 and the beam scanning control device 3 according to the flow of the flowchart (details will be described later) shown in FIG. Ask for These pieces of aircraft information are sent to the display 11 and displayed on the screen. The operation of the above configuration will be described below.

First, it is assumed that the antennas 1 and 2 are arranged at the origin O of the (AA ', BB') coordinate system shown in FIG. 3 (a). The beam surface BM1 by the antenna 1 is B-
It is formed along B'and is swung in the AA 'direction. The beam surface BM2 formed by the antenna 2 is formed along AA 'and is swung in the BB' direction. Incidentally, A-A ',
The direction of BB 'is preferably north, south, east and west.

Considering the case where the aircraft enters the coverage area of the antennas 1 and 2, the beam surfaces BM1 and BM2 intersect at the position of the aircraft P by shaking the beam surfaces BM1 and BM2 at high speed. Beam deviation angle θ of beam plane BM1 when the aircraft intersects each beam plane at position P in the figure
(An angle formed by the vertical direction Z of the origin O and BM1) is shown in FIG.
FIG. 3C shows the beam deviation angle ρ of the beam surface BM2 (angle formed by the vertical direction Z of the origin O and BM2). The operation at this point will be described below with reference to the flowchart of FIG.

First, pulse signals from the transmitters 4 and 5 are radiated from the antennas 1 and 2 (step a),
The reflected pulse signal reflected by the aircraft P is transmitted to each antenna 1,
2 is received and detected by each of the monopulse receivers 8 and 9 (step b), the information processing device 10 determines that each beam surface BM
1, receives the pulse transmission timing information and the reflection pulse reception timing information in BM2, and obtains the time difference between the reflection pulse reception timing and the pulse transmission timing,
Slant range R on each beam surface BM1, BM2
Calculate r (step c). The slant range R, r is the distance between OPs, and R = r.

Next, the information processing device 10 performs monopulse angle measurement from the beam scanning direction information from the beam scanning control device 3 and the received information from the receivers 8 and 9 to obtain each beam surface B.
The shift angles θ and ρ of M1 and BM2 are calculated. Then, for each of the beam surfaces BM1 and BM2, an arc having a radius of the slant ranges R and r is assumed as shown in FIG. 4, and the coordinates of the intersection point P are obtained (step d).

Further, the information processing apparatus 10 projects the coordinates of the intersection P on the Z axis to obtain the height of the aircraft P (step e), and projects it on the ground coordinates to obtain the height from the reference direction (A in FIG. 4). An angle φ (an azimuth angle if A is north) and a distance (ground range) γ from the origin O are obtained (step f).
The information of H, φ, γ thus obtained is displayed on the display unit 11.
And is displayed on the screen as shown in FIG. 5 (step g).

In FIG. 5, a reference line is drawn on the OA in the two-dimensional coordinate system defined by (A-A ', BB'), and the reference line is rotated by φ, so that only a distance γ from the origin O is obtained. The symbol x of the aircraft is displayed at a distant position, and the height H is displayed as a number in the vicinity thereof.

Therefore, the aircraft monitoring device having the above-described structure swings the beam planes orthogonal to each other at a high speed, assumes an arc passing through the position P of the aircraft, and obtains the coordinates of the intersection point P. Therefore, the on-board transponder. The altitude of the flying object can be measured with high accuracy without depending on.

In the above embodiment, the case where the target flying object is an aircraft has been described, but a flying object such as a missile can be similarly displayed. In particular, the effect is extremely large for a flying object that does not have a transponder. Further, when a plurality of flying objects enter the coverage area of the antennas 1 and 2, by adding an SSR and reading the identification information from each aircraft, the symbols of the plurality of flying objects are displayed on the same screen. You can also do it. Needless to say, the present invention can be similarly implemented even if various modifications are made without departing from the scope of the present invention.

[0022]

As described above, according to the present invention, it is possible to provide a flying object monitoring apparatus capable of highly accurately measuring the altitude of a flying object without depending on the onboard transponder.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a flying body monitoring apparatus according to the present invention.

FIG. 2 is a flowchart for explaining an information processing operation of the embodiment.

FIG. 3 is a conceptual diagram for explaining the movement of the beam surface of the embodiment.

FIG. 4 is a conceptual diagram showing how to obtain the direction, distance and height of a target aircraft according to the embodiment.

FIG. 5 is a diagram showing an example in which the information obtained in FIG. 4 is displayed on the screen according to the embodiment.

[Explanation of symbols]

1, 2 ... Beam scanning antenna, 3 ... Beam scanning control device, 4, 5 ... Transmitter, 6, 7 ... Transmission / reception switcher, 8, 9 ... Monopulse receiver, 10 ... Information processing device, 11 ... Display device.

Claims (2)

[Claims] 1. A fan-shaped beam surface is formed by scanning beams of first and second antennas, each of which forms a beam having a substantially narrow width, and beams of the first and second antennas, which are orthogonal to each other. In addition, a beam scanning control device that swings each beam surface in a direction orthogonal to each other, and a pulse transmission / reception means that radiates a pulse signal through the first and second antennas and receives and detects a reflected pulse signal from a target flying object. By this means, the slant range is obtained from the time difference between the reflected pulse signal obtained from the first and second antenna reception outputs with respect to the transmission pulse signal, and each antenna beam deviation angle at the time of reception is obtained. Assuming an arc with the radius of the slant range on each beam surface of the first and second antennas based on
A flying body monitoring apparatus comprising: an information processing apparatus that obtains the height and the ground range of the target flying body from the intersection; and a display that displays the height and the ground range obtained by the information processing apparatus. 2. The flying object monitoring apparatus according to claim 1, wherein the first and second antennas are electronic scanning antennas.