WO2000040994A1

WO2000040994A1 - Radar device

Info

Publication number: WO2000040994A1
Application number: PCT/JP2000/000014
Authority: WO
Inventors: Yoshiaki Asou; Hiroyuki Iida; Tomoaki Konno; Yuuji Sekine
Original assignee: Kabushiki Kaisha Koden Seisakusho
Priority date: 1999-01-07
Filing date: 2000-01-06
Publication date: 2000-07-13
Also published as: JP2000206225A; JP3507717B2

Abstract

Areas at different observation distances are parallel observed under respective optimal conditions. The observation distances in a scanning range of a beam are specified by observation distance specifying means (23). Trigger pulses having widths corresponding to the specified observation distances are generated by first and second pulse generating means (25, 26) and switched by pulse switching means (27) at predetermined timings. The switched trigger pulses are inputted into a transmitter (32). The observation coordinates corresponding to the specified observation distances are displayed on a display (39), and the images of echo signals obtained by the trigger pulses having different widths are displayed on the corresponding observation coordinates.

Description

00/4 T / JP00 /

Description Radar equipment Technical field

The present invention relates to a technique for enabling a radar device to perform short-range observation and long-range observation in parallel.

The radar device intermittently emits an observation wave such as a radio wave in synchronization with a trigger pulse while scanning the beam direction of the antenna within a predetermined range, receives the reflected wave, and receives an echo signal indicating the intensity of the reflected wave. Based on the scanning direction signal indicating the beam direction of the antenna and the antenna, the image of the object in the observation target area is displayed on coordinates where the distance and direction from the reference position can be visually recognized. Background art

In such a radar system, when observing a short-distance region, the observation wave is emitted by a narrow trigger pulse so that the dead zone due to the emission time width of the observation wave can be reduced and a nearby object can be identified. However, when observing a distant region, it is necessary to emit the observation wave with a wide trigger pulse so that the reflected wave from a distant object can be received with high sensitivity.

Therefore, in the conventional radar system, when the observation distance is specified, a trigger pulse with a width corresponding to the observation distance is input to the transmitter, and an observation wave with a time width corresponding to the width of the trigger pulse is emitted. Was composed.

However, in the conventional radar system, for example, in order to perform short-range observation and long-range observation in parallel, it is necessary to frequently change the specification of the observation range by manual operation. Each time the designation is changed, the displayed image changes drastically, making observation difficult. In order to solve this, for example, an image with the function of enlarging the image of observation data obtained by specifying a long distance and displaying it as a short distance observation image has been realized, but it is simply enlarged in this way. In the images, the objects corresponding to the distance resolution or less could not be observed due to the large dead zone, and it was not possible to observe under optimal conditions for the observation distance.

An object of the present invention is to solve this problem and to provide a radar apparatus capable of observing a plurality of regions at any observation distance in parallel under optimum conditions. Disclosure of the invention

In order to achieve the above object, a radar device of the present invention

An antenna (3 1)

A transmitter (32) for emitting an observation wave from the antenna for a time corresponding to the width of the trigger pulse each time a trigger pulse is received;

Each time the transmitter emits an observation wave, a receiver (33) that receives a reflected wave of the observation wave via the antenna and outputs an echo signal indicating the intensity of the reflected wave; and a beam of the antenna. Beam scanning means (34) for scanning a direction within a predetermined range and outputting a scanning direction signal indicating the scanning direction;

Specify a plurality of observation distances for the scanning range of the beam scanning means

Distance designation means (2 3) for

A trigger pulse having a width corresponding to each of a plurality of observation distances specified by the observation distance specifying means is configured to be generated, and a trigger input to the transmitter while switching the trigger pulse of each width at predetermined times. Pulse input means (25, 26, 27) and

An indicator (39);

A plurality of observation distances respectively corresponding to the plurality of observation distances designated by the observation distance designation means. Display control for displaying the number of observation coordinates on the screen of the display unit and displaying the image of the echo signal corresponding to the observation wave emitted from the transmitter by the trigger pulse of each width on the corresponding observation coordinate. Means (38). FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a timing chart for explaining the operation in the single screen mode of the embodiment.

FIG. 3 is a diagram showing an example of an observation screen in the single screen mode.

FIG. 4 is a timing chart for explaining the operation in the multi-screen mode of the embodiment.

FIG. 5 is a diagram showing an example of an observation screen in the multi-screen mode.

FIG. 6 is a diagram showing another example of the observation screen in the multi-screen mode.

FIG. 7 is a timing chart for explaining another operation example in the multi-screen mode. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a configuration of a radar device 20 of the embodiment.

In FIG. 1, a display mode designating means 21 designates one of a single screen mode and a multi-screen mode by key operation or the like. The observation coordinate system designating means 22 converts the coordinate system consisting of the direction axis and the distance axis of the observation screen displayed by a key operation or the like from polar coordinates (PPI), XY coordinates (SEMI 3D), etc. If a single screen mode is specified by the display mode specification means 2 1, any one of a plurality of coordinate systems can be specified, and the multi-screen mode is specified. If you have multiple coordinate systems Any two of them can be specified (they may be the same). The observation distance designating means 23 is used to designate the size of the observation distance by a key operation or the like, and when the single screen mode is designated by the display mode designating means 21, a single observation distance is designated. The observation distance La can be specified, and when the multi-screen mode is specified, the two observation distances La and Lb can be specified independently.

The first pulse generation means 25 constitutes a trigger pulse input means of this embodiment together with a second pulse generation means 26 and a pulse switching means 27 which will be described later. A trigger pulse Pa having a width corresponding to the specified distance La is generated, and the second pulse generating means 26 generates a trigger having a width corresponding to the distance Lb specified by the observation distance specifying means 23. Generates pulse Pb.

The pulse switching means 27 always selects the trigger pulse Pa output from the first pulse generating means 25 when the single screen mode is designated by the display mode designating means 21. When the multi-screen mode is designated, the trigger pulse Pa output from the first pulse generating means 25 and the trigger pulse Pa output from the second pulse generating means 26 are output. Scanning unit 3

Each time the scanning direction signal φ from 0 becomes a predetermined value (for example, 0), the switching is performed.

Output to 0.

On the other hand, the scanning unit 30 includes an antenna 31, a transmitter 32, a receiver 33, and a beam scanning device 34.

Each time the transmitter 32 receives the trigger pulse from the pulse switching means 27, the antenna 31 emits a radio wave of a predetermined frequency as an observation wave for the width of the trigger pulse, and the receiver 33 receives the transmitter 33. Immediately after the observation wave is emitted from 32, a reflected wave of the same frequency as that of the transmitter 32 is received via the antenna 31 for a predetermined time, and an echo signal E indicating the intensity of the received reflected wave is output. The beam scanning device 34 rotates the beam direction of the antenna 31 by, for example, 360 degrees along a horizontal plane, and outputs a scanning direction signal φ (in this case, a signal indicating an azimuth angle) corresponding to the beam direction. .

The echo signal E output from the scanning unit 30 is input to the echo signal processing circuit 35, amplified, STC processed, and FTC processed, and stored in the observation data memory 37 by the data writing unit 36. The STC processing is to prevent the effects of darkness due to terrain and sea surface reflections, and the FTC processing is to remove the noise due to the reflection of continuous waves, rain, snow, etc. It is.

The data writing means 36 decodes the echo signal E 'processed for each trigger pulse by the echo signal processing circuit 35, and the single screen mode is specified by the display mode specifying means 21. In this case, the data is sequentially stored in the address area of the observation data memory 37 corresponding to the value of the scanning direction signal φ from the scanning unit 30.

In addition, when the multi-screen mode is designated by the display mode designating means 21, the data writing means 36 divides the observation data memory 37 into two storage areas 37 a and 37 b. While the scanning unit 30 is scanning with the trigger pulse Pa generated from the first pulse generation means 25, the data stream of the echo signal E 'output from the echo signal processing circuit 35 is displayed. Are sequentially stored in the address area corresponding to the value of the scanning direction signal φ in the storage area 37 a of the scanning section 30, and the scanning section 30 scans with the trigger pulse Pb generated from the second pulse generation means 26. In the meantime, the sequence of echo signals E 'output from the echo signal processing circuit 35 is sequentially stored in an address area corresponding to the value of the scanning direction signal Φ in the other storage area 37b.

The display control means 38 reads out the data of the echo signal E 'stored in the observation data memory 37, and reads the data of the display mode specifying means 21, the observation coordinate system specifying means 22 and the observation distance specifying means 23. The observation screen corresponding to the specified contents is displayed on the display unit 39. That is, when the single screen mode is designated by the display mode designating means 21, The coordinate system specified by the observation coordinate system specifying means 22 is displayed on a scale corresponding to the distance La specified by the observation distance specifying means 23, and an echo signal E ′ for each direction is displayed on the coordinates. To display the night.

When the multi-screen mode is designated by the display mode designating means 21, the two coordinate systems designated by the observation coordinate system designating means 22 are divided by the two distances designated by the observation distance designating means 23. Displayed on a scale corresponding to L a and L b, and one of the coordinate systems displays the data of the echo signal E ′ stored in one storage area 37 a of the observation data memory 37. Then, the data of the echo signal E ′ stored in the other storage area 37 b of the observation data memory 37 is displayed in the other coordinate system.

In the radar apparatus 20 configured as described above, when the scanning direction signal Φ is output as shown in FIG. 2A, for example, a single screen mode is set by the display mode designating means 21. When the PPI is specified by the observation coordinate system specification means 22 and the short distance is specified by the observation distance specification means 23, the first pulse generation means 25 is used as shown in Fig. 2 (b). A trigger pulse Pa having such a narrow width is generated, and is input from the pulse switching means 27 to the scanning section 30.

Radio waves are emitted from the scanning unit 30 for a time corresponding to the width of the trigger pulse Pa, and as shown in (c) of FIG. The echo signal E 'is obtained from the reflected wave received at 0, and the data is sequentially stored in the observation data memory 37 as observation data for each direction. The display control means 38 displays the PPI coordinates consisting of a circular scale corresponding to the distance La specified by the observation distance specifying means 23 on the display 39, as shown in FIG. 3, for example. The data of the echo signal E 'stored in the observation data memory 37 is read out and displayed on these coordinates.

In addition, the multi-screen mode is specified by the display mode If the PPI is specified as the two coordinate systems by the target system specifying means 22 and the short distance and the long distance are specified by the observation distance specifying means 23, the first pulse generating means 25 As shown in Fig. 4 (a), a narrow trigger pulse Pa is output as shown in Fig. 4 (a), and a wide trigger pulse Pb is output as shown in Fig. 4 (b) from the second pulse generating means 26. These two types of trigger pulses are switched as shown in (d) of FIG. 4 each time the scanning direction signal φ ((c) of FIG. 4) becomes equal to 0 (each time the antenna 31 rotates once). The signals are alternately switched by means 27 and input to the scanning unit 30.

During the period in which the scanning unit 30 receives the trigger pulse Pa, the radio wave is emitted for the time during which the trigger pulse Pa is received as described above, and as shown in FIG. 4 (e), the trigger pulse P a The data of the echo signal E 'of the reflected wave received during the predetermined time T1 from the fall timing of the data is stored in one storage area 37a of the observation data memory 37 as the observation data for each direction. You.

Similarly, during the period when the scanning unit 30 receives the trigger pulse Pb, the radio wave is emitted only during the time during which the trigger pulse Pb is received, and the predetermined time is set after the falling of the trigger pulse Pb. The data of the echo signal E 'of the reflected wave received during the time T2 is stored in the other storage area 37b of the observation data memory 37 as observation data for each direction.

As shown in FIG. 5, the display control means 38 includes a first PPI coordinate G 1 composed of a circular scale corresponding to the observation distance La specified by the observation distance specifying means 23, and an observation distance specifying means 2 3 And the second PPI coordinate G 2 consisting of a circular scale corresponding to the observation distance L b specified by, is displayed on the display unit 39, and stored in one storage area 37 a of the observation data memory 37. The observation data for each direction is read and displayed on the first PPI coordinate G1, and the observation data for each direction stored in the other storage area 37b of the observation data memory 37 is read and the second observation data is read. Table on PPI coordinate G2 Show.

For this reason, two observation distances arbitrarily specified for the beam scanning range can be observed in parallel under the optimum conditions for each observation distance.

In the multi-screen mode, when one observation coordinate system is designated as SEMI 3D, as shown in Fig. 6, the azimuth is the horizontal axis and the distance is the vertical axis. 3 is displayed together with the PPI coordinates G 1, and the observation data for each direction stored in the other storage area 37 b of the observation data memory 37 is displayed.

In the above-described embodiment, the trigger pulse is switched every time the scanning direction signal φ from the scanning unit ³⁰ reaches a predetermined value, that is, every time the antenna 31 makes one rotation. Alternatively, the trigger pulse may be switched every time the azimuth of the antenna 31 changes by one step, or the trigger pulse may be switched at regular intervals irrespective of the scanning direction signal Φ.

In the above-described embodiment, the trigger pulses independently generated by the first and second pulse generation units are selectively input to the scanning unit. However, the pulse width is designated for the single pulse generation unit. The trigger signal having a different width may be switched and input to the scanning unit by switching and inputting the signal to be performed at predetermined timings.

In the above embodiment, two observation distances can be specified. However, three or more observation distances may be specified.

Further, by changing the processing conditions of the echo signal processing circuit in synchronization with the switching of the trigger pulse, the optimal STC processing and FTC processing may be performed according to the observation distance. Industrial applicability

As described above, the radar apparatus according to the present invention is capable of observing the beam scanning range. A plurality of distances can be specified, trigger pulses of a width corresponding to the specified observation distances are input to the transmitter while switching at predetermined intervals, and a plurality of trigger pulses corresponding to the specified observation distances are input. The observation coordinates are displayed on the display screen, and the echo signal images obtained by the trigger pulses of each width are displayed on the corresponding observation coordinates.

For this reason, observations at a plurality of observation distances arbitrarily specified for the beam scanning range can be performed in parallel under the optimum conditions for each observation distance.

Claims

0 Claims

1. Antenna (3 1)

Observation distance designation means (23) for designating a plurality of observation distances with respect to a scanning range of the beam scanning means;

A trigger pulse having a width corresponding to each of a plurality of observation distances specified by the observation distance specifying means is configured to be generated, and a trigger input to the transmitter while switching the trigger pulse of each width at a predetermined timing. Pulse input means (25, 26, 27) and

An indicator (39);

A plurality of observation coordinates respectively corresponding to the plurality of observation distances designated by the observation distance designation means are displayed on the screen of the display unit, and the observation wave emitted by the transmitter by the trigger pulse of each width is displayed. A radar device comprising display control means (38) for displaying an image of an echo signal on a corresponding observation coordinate.