JPH05256929A - Rader apparatus - Google Patents

Abstract

PURPOSE:To obtain a radar apparatus, which can obtain the position information of a target without visual observation. CONSTITUTION:A radar transmitter 11, which emits radar radio waves based on a synchronizing signal (c), a radar receiver 13, which receives the reflected wave obtained by the reflection of the radar radio waves from a specified target and generates a video signal (a), a PPI indicator 36, which displays the position of the target based on the video signal, and a gate generating means 17, which specifies the target displayed on the screen of the indicator and generates the specified gate, are provided. Furthermore, a first detecting means 19, which detects the first pulse rising time in the range specified by the specified gate among the video signals, a second detecting means 20, which detects the second pulse rising time that agrees with the emitting time of the radar radio wave among the synchronizing signals, are provided. A distance-data converting means 23, which converts the distance data of the target based on a difference 21 between the first and second pulse-rise times is further provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radar device which can easily and accurately obtain position information such as a distance and direction to a target without visual inspection.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a radar apparatus main body 30 of this type of radar apparatus includes a transmitter 31 and a transmission antenna 32 which radiate radio waves by dividing them into short pulses.
It has a receiving antenna 34 (often shared with the transmitting antenna 32) for receiving a reflected wave reflected from a desired target 33 and a receiver 35, receives a synchronization signal a from the transmitter 31, and receives it from the receiver 35. Is composed of an indicator 36 which receives the video signal b and displays it on the screen.

The synchronizing signal a and the video signal b are shown in FIG.
As shown in, if the S portion of the video signal b is due to the reflection of a desired target and the time when the synchronization signal a is emitted is the same as the time when the radar radio wave is emitted, the time from ts to the target is reached. Distance can be obtained.

A method for visually determining the distance to the target based on the time ts is, for example, PPi (Plan Position In
dicater) is well known.

[0005] PPi is a CRT (Cathode Ray Tub) having an electron gun that emits an electron beam capable of scanning and a screen screen that shines where the electron beam is irradiated.
e) and scanning of the electron beam is performed radially from the center of the screen, but the radar radio wave emission direction and the scanning direction are made to correspond. As a result, the intensity of the electron beam irradiation is adjusted based on the input video signal, so that the screen shines to the maximum corresponding to the peak of the video signal. An example of the PPi screen is shown in FIG.

In order to specify a specific target (bright spot) on the screen of the indicator 36 and detect the position of this target, conventionally, the position on the screen is visually observed from the distance from the center of the screen. Was specified and converted from the position on this screen to the actual position (direction and distance).

[0007]

However, the conventional visual reading operation on the screen is not only time-consuming, but also has the drawback of causing eye fatigue and visual reading errors.

Therefore, in view of the above-mentioned drawbacks, a technical object of the present invention is to provide a radar device capable of obtaining position information of a target without visual inspection.

[0009]

According to the present invention, a radar transmitter that emits a radar radio wave based on a predetermined synchronization signal and a reflected wave obtained by reflecting the radar radio wave on a predetermined target object are provided. A radar device having a radar receiver for receiving and generating a video signal, wherein the radar device has a calculation means for calculating position information regarding the target object based on the synchronization signal and the video signal. Be done.

Further, according to the present invention, a radar transmitter that emits a radar radio wave based on a predetermined synchronization signal and a reflected wave obtained by reflecting the radar radio wave on a predetermined target object are received, and a video signal is received. In a radar device having a radar receiver for generating a signal and an indicator for displaying the position of the target on the screen based on the video signal, the target displayed on the screen of the indicator is designated. And a gate generating means for generating a designated gate, and the video signal,
A first pulse (echo pulse) generated from the video signal within a range defined by the designated gate
A first detecting means for detecting a rising time point; a second detecting means for detecting a rising time point of a second pulse (synchronization pulse) of the synchronization signal which coincides with the emission of the radar radio wave; A radar device having a distance data conversion means for converting the distance data of the target from the difference between the rising times of the second pulses is obtained.

Further, according to the present invention, in the radar device, the azimuth data of the target object is generated based on an antenna that radiates the radar radio wave or receives the reflected wave and a driving direction of the antenna. And a direction data conversion means for controlling the direction.

That is, according to the present invention, after the target is set, the target position is not calculated from the bright spot on the indicator screen, but the position information is directly calculated based on the synchronization signal and the video signal. Is.

[0013]

Operation: A touch panel is provided so as to cover the indicator screen, a bright spot which is a target image on the screen is found through the touch panel, and the operator designates the target image portion on the touch panel surface by touching it with a fingertip or the like.

A normal touch panel is assumed to have a rectangular screen, and the obtained designated position, that is, the address data of the touched portion is indicated by xy coordinates. This is converted into a polar coordinate position so that the PPi screen shown in FIG.

For example, as shown in FIG. 6, xy of the contact point
Considering the inside of a circle centered on the coordinate value as the designated area, and detecting the position of the target (bright spot) in this area, in order to convert the xy coordinates into polar coordinates, as shown in FIG.
The distance r from the center and the angle θ are calculated as follows.

R = √ (x ² + y ² ) θ = tan ⁻¹ x / 2 In the direction of the angle θ, focusing on the video signal corresponding to the reflected wave when the radar radio wave is emitted, the circle in the specified area is , As shown in FIG. 8, converted into a gate on the time axis of the video signal.

If the time at which scanning starts from the center of PPi coincides with the time at which radar radio waves are emitted,
The distance to the target is calculated from the time required from the scanning start time to the peak existing in the gate.

[0018]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 shows signal waveforms at respective parts in the operation block diagram.

The radar wave radiated from the transmitter 11 via the transmission / reception antenna 12 is reflected by the object and reaches the receiver 13 via the transmission / reception antenna 12 as a reflected wave. The receiver 13 generates the state of the reflected wave as the video signal a. The threshold level generation circuit 14 generates a threshold level b of a predetermined DC voltage.

The comparator 14 compares the video signal a with the threshold level b, and outputs the comparator output d.
To generate.

The PPi indicator 36 is composed of an electron gun for ejecting an electron beam capable of scanning, and a CRT having a screen screen where a portion irradiated with the electron beam shines. The scanning of the electron beam is performed radially from the center of the screen, the radar radio wave emission direction and the scanning direction are made to correspond to each other, and based on the input video signal a,
The intensity of electron beam irradiation is adjusted, and the peak of the video signal a appears as a bright spot on the screen.

The touch panel 16 is provided so as to be overlapped with the PPi indicator 36, and a bright point on the screen is designated by touching it with an operator's fingertip or the like, whereby a target coordinate signal indicating a location of a target image on the surface of the touch panel is generated. , Gate creation circuit 1
Output to 7. The gate creating circuit 17 generates a gate signal e that defines a gate corresponding to the target coordinate signal.

The AND circuit 18 selects only one of the comparator outputs d defined by the gate signal e.
This is the selected echo pulse f. The first rising differential detection circuit 19 differentiates the rising of the selected echo pulse f to generate a first pulse (echo pulse) rising time detection pulse g indicating the rising time.

On the other hand, the second rising differential detection circuit 20 is
The second pulse (synchronization pulse) rising time detection pulse h of the synchronization signal c obtained from the radar transmitter 11 is generated.

The counting circuit 21 uses the clock signal i from the timer generation circuit 22 as a reference, from the second pulse rise position detection pulse h to the first pulse rise time detection pulse g.
It counts the number of clocks included in and outputs a count signal.

The distance conversion calculation circuit 23 generates target distance data based on the count signal. The target azimuth data is converted and generated by the azimuth calculation circuit 25 based on the antenna direction information signal indicating the antenna direction obtained from the antenna drive circuit 24.

In FIGS. 1 and 2, j is a reference timing pulse.

[0029]

As described above, according to the present invention, when the operator finds a target image (bright spot) on the screen on which the touch panel is overlaid and then touches it with a fingertip or the like, the target position (distance And (azimuth) information is automatically calculated and calculated, position detection by visual inspection of the operator's screen is not required, which not only reduces the burden on the operator, but also has the effect of accurately and quickly obtaining target position information.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a signal waveform diagram of each part shown in FIG.

FIG. 3 is a basic principle diagram of a radar device.

FIG. 4 is a diagram showing an example of periodic signal and video signal waveforms.

FIG. 5 is a diagram showing an example of a PPi screen.

FIG. 6 is a conceptual diagram in which a touch panel is overlaid on a PPi screen.

FIG. 7 is a diagram showing a relationship between xy coordinates and polar coordinates.

FIG. 8 is a conceptual diagram showing a relationship between a video signal and a gate on a time axis.

[Explanation of symbols]

11 radar transmitter 12 transmission / reception antenna 13 radar receiver 14 threshold level generation circuit 15 comparator 16 touch panel 17 gate creation circuit 18 AND circuit 19 first rising differential detection circuit (echo pulse rising time detection) 20 second rising differential detection circuit (Synchronous pulse rise time detection) 21 Counting circuit 22 Timer generating circuit 23 Distance conversion calculation circuit 24 Antenna drive circuit 25 Direction calculation circuit 36 PPi indicator

Claims (3)

[Claims] 1. A radar transmitter that emits a radar radio wave based on a predetermined synchronization signal, and a radar receiver that receives a reflected wave obtained by reflecting the radar radio wave on a predetermined target and generates a video signal. A radar device including: a radar device including a calculation unit that calculates position information regarding the target object based on the synchronization signal and the video signal. 2. A radar transmitter that emits a radar radio wave based on a predetermined synchronization signal, and a radar receiver that receives a reflected wave obtained by reflecting the radar radio wave on a predetermined target and generates a video signal. In a radar device having an indicator that displays the position of the target on the screen based on the video signal, the target displayed on the screen of the indicator is designated, and a designated gate is opened. Gate generating means for generating; first detecting means for detecting a first pulse rising time point generated from the video signal within a range defined by the designated gate in the video signal; Of these, the distance between the target and the second detection means for detecting a second pulse rising time point that coincides with the emission of the radar radio wave, and the difference between the first and second pulse rising time points. Radar apparatus characterized by having the distance data conversion means for converting the over data. 3. The radar device according to claim 2, wherein an antenna that radiates the radar radio wave or receives the reflected wave, and an azimuth that generates azimuth data of the target based on a driving direction of the antenna. A radar device comprising a data conversion means.