JP2001201563A - Radar device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radar device provided with a small-sized and inexpensive body part of the latter stage including a display part and having a high renewing speed of display image and a high control responsiveness of image quality improvement. SOLUTION: In this radar device, a sensor part 1 of the front stage equipped with a transmitter-receiver part 11, a rotating scanning part 21 and a signal processing part 20 is connected to a display and control part 2 of the latter stage equipped with display parts 2b and 2e and control command transmission parts 2a and 2c through serial transmission lines 3 and 4. The signal processing including the coordinate conversion from a polar coordinate system to an orthogonal two-dimensional coordinate system by the signal processing part 20, the transfer of an image signal on the serial transmission lines, and the display of the image signal by the display and control part 2 are performed every quadrant of the orthogonal two-dimensional coordinate system synchronously to the rotating scanning by the rotating scanning part 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radar device mounted on a ship or the like, and particularly relates to a rear portion including a display device, which is compatible with a general-purpose data processing device such as a personal computer. It is about.

[0002]

2. Description of the Related Art A radar device is mounted on a boat such as a fishing boat. Japanese Patent No. 2968386 discloses that a radar image is displayed by transferring an image signal obtained by performing coordinate conversion from a polar coordinate system to an orthogonal two-dimensional coordinate system to a display unit in a sensor unit called an antenna unit at the preceding stage of a radar apparatus. A radar apparatus has been disclosed in which a main body called a display installed in a steering room or the like is reduced in size.

[0003]

In the above prior art,
Since the video signal of the radar screen transmitted from the sensor unit to the display unit is a high-frequency signal, there is a demand to transmit this as a low-frequency signal. In a radar device that is divided into a sensor unit and a main unit that satisfies such requirements, the image signal of the orthogonal two-dimensional coordinate system generated by the sensor unit is transferred to the main unit for each screen, and one screen being displayed is displayed. Is updated. The update period for one screen is equal to the time required for one rotation of the antenna and is a large value of about 2 to 3 seconds. As described above, when the update speed of the screen is reduced, there is a problem that the movement of the reflecting object moving in the display screen lacks smoothness and becomes difficult to see. Accordingly, it is an object of the present invention to smooth the movement of a reflective object in a display screen by increasing the update speed of the screen.

In addition, the sensor unit executes a command input by the user to the main unit with respect to the display method and the image quality of the screen with a delay of two to three seconds, which is an update cycle of one screen. Gives the user a feeling of frustration. Therefore, another object of the present invention is to provide a radar apparatus in which operability is improved by improving responsiveness to a control command relating to display.

[0005]

A radar apparatus according to the present invention for solving the above-mentioned problems of the prior art transmits and receives a radio wave and receives a reflected wave as a reception signal, and a direction of transmission and reception of the radio wave by the transmission and reception section. A rotation scanning unit for rotating the image signal; a signal processing unit for A / D converting a reception signal of the transmission / reception unit into a digital signal and performing coordinate conversion from a polar coordinate system to an orthogonal two-dimensional coordinate system; A sensor unit including a data transmission unit that transmits an image signal created by a processing unit onto a serial transmission path, a display unit that receives the image signal from the sensor unit through the serial transmission path, and displays the image signal; And a display / control unit including a control signal transmitting unit that transmits a control signal via a transmission path to the unit. The signal processing by the signal processing unit of the sensor unit, the transmission of the image signal by the data transmission unit, and the display of the image display by the display / control unit are synchronized with the rotation scanning by the rotation scanning unit in the quadrant of the orthogonal two-dimensional coordinate system. Each time, the update speed of the display screen is increased.

[0006]

According to a preferred embodiment of the present invention, among the control commands transmitted from the display / control unit, those related to the improvement of the image quality of the image signal are described next to the quadrant being processed. By starting from the image signal in the quadrant, a high-speed response to the control is realized.

According to another preferred embodiment of the present invention,
The display / control unit is equipped with a drawing processing unit that draws display data such as markers, symbols, and numerical values that are displayed by being superimposed on the image signal, thereby reducing the load on the sensor unit and reducing the size and cost. Has been realized.

[0008]

FIG. 1 is a functional block diagram showing the configuration of a radar apparatus according to one embodiment of the present invention. In the radar apparatus of this embodiment, a sensor unit 1 and a general-purpose personal computer 2 used as a display unit are interconnected by a serial transmission line 3 for transferring control data and a serial transmission line 4 for transferring display data. It has a connected configuration.

The sensor unit 1 comprises a processor 10, a transmitter 1
1, transmission / reception separator 12, directional antenna 13 for both transmission / reception,
Receiving amplifier 14, mixer 15, local oscillator 16, intermediate frequency amplifier 17, A / D converter 18, data memory 19,
It includes a coordinate converter 20, a rotation scanning unit 21, and a communication interface unit 22.

The transmitting unit 11 transmits a carrier wave of several GHz to several μsec.
A transmission pulse having a constant period is created by amplitude-modulating the pulse with a width of the order. This transmission pulse is supplied to the directional antenna 13 for transmission and reception through the transmission / reception separator 12 and transmitted in the air. The reflected wave of the transmitted radio wave from the object is received by the directional antenna 13 for both transmission and reception, and the received signal is supplied to the reception amplifier 14 via the transmission / reception separator 12, amplified and supplied to the mixer 15.

The received signal supplied to the mixer 15 is
The signal is mixed with a local oscillation signal in the same frequency band as the carrier supplied from the local oscillator 16 and converted into a low-frequency intermediate frequency signal. This intermediate frequency signal is supplied to the intermediate frequency amplifier 17.
After that, the signal is converted into a digital signal at a predetermined sampling cycle in the A / D converter 18 and written into the data memory 19.

The rotary scanning unit 21 performs rotary scanning in the radiation direction of the beam by rotating the radiation direction of the beam from the directional antenna 13 for transmission and reception at a predetermined cycle over 360 °. The rotation scanning of the beam is performed in synchronization with the transmission of the pulse and the operation of receiving the reflected wave. Therefore, a received signal that appears over a certain time width is a reflected wave received from each of a plurality of directions set at a fixed angle interval.

A coordinate converter 20 is based on the information on the beam radiation direction received from the rotary scanning unit 21 and the time information indicating the arrangement position of the pixel signals output from the A / D converter 18. A memory address for changing the arrangement order of the pixel signals for the display to the arrangement order for (X, Y) coordinate display is generated and supplied to the address terminal of the data memory 19. As a result, the pixel signal output from the A / D converter 18 is converted from an image signal for polar coordinate display to an image signal of a (X, Y) coordinate system in which a display position is managed by (X, Y) coordinates. While writing to the data memory 19.

The amount of data decreases with the coordinate conversion processing by the coordinate converter 20. That is, in the (X, Y) coordinate system, the pixel signal density is determined by the interval between the vertical and horizontal scanning lines, and is constant regardless of the position in the display screen. On the other hand, in the polar coordinate system, the distance between the scanning lines on the radiation increases as the distance from the origin increases, so that the density of the pixel signals arranged on these scanning lines is as far away as the orthogonal coordinate system. If the value is maintained, the pixel signals are too close to each other near the origin, resulting in an excessive data amount. An excessive pixel signal group in the local coordinate system near the origin is
By overwriting at the same pixel position in the (X, Y) coordinate system, those other than the last written pixel signal are discarded, and the data amount is reduced.

When the rotational scanning of the directional antenna 13 for transmission and reception is completed in the first quadrant range from 0 ° to 90 °, the processor 10 outputs the image signal of the first quadrant that has just finished this scanning from the data memory 19. The data is read and transferred to the personal computer 2 via the interface circuit 22 and the serial transmission path 4. Similarly, when the writing of the image signals in the fourth quadrant, the third quadrant, and the second quadrant to the data memory is completed, the processor 10 reads the image signal in the quadrant in which the writing has been completed from the data memory 19, and The data is transferred to the personal computer 2 via the serial transmission line 4.

The processor 10 integrates the levels of all pixel signals included in one quadrant of the image signal read from the data memory 19 in parallel with the digital image signal transfer processing, and calculates one quadrant of the video signal. The integrated value is added to the end of the signal. The image signal for one quadrant is transferred from the interface unit 21 to the personal computer 2 through the serial transmission line 4.

In the personal computer 2, an image signal for one quadrant is transferred to the CPU 2a through the interface 2c. When receiving the transferred image signal for one quadrant, the CPU 2a writes the image signal in the screen memory 2d and integrates the levels of the respective pixel signals. And CPU2
In a, the integrated value of the pixel signal of one quadrant is compared with the integrated value of the pixel signal of one quadrant added by the processor of the sensor unit 1 and added to the end of the transfer data.

When the two integrated values match, the CPU 2a determines that no code error has occurred during transmission, and updates the image data in the corresponding quadrant with this one quadrant video signal. On the other hand, if the two integrated values do not match, it is considered that a code error has occurred during transmission,
The received video signal for one quadrant is discarded. If the integrated value is excessive, the upper digit is discarded, and only the lower predetermined digit portion is collated.

As described above, since the display screen is updated in units of one quadrant, not in units of one screen, the average update speed for the entire screen is improved. That is, FIG.
The screen is updated for each of the first to fourth quadrants indicated by (IV). On the other hand, in the conventional one-screen unit processing, the screens of the preceding first quadrant, fourth quadrant, and third quadrant that have already been generated until the last pixel signal in the second quadrant can be updated. Is not performed, a useless update wait time occurs, and the screen update speed decreases.

When the CPU 2a receives the control command input from the input unit 2f, it transfers it to the serial transmission line 3 via the interface unit 2c. This control command is transferred to the processor 10 via the serial transmission line 3 and the interface 22 of the sensor unit 1. Processor 10
Means that the control command transmitted from the personal computer 2 is tuned (tuned), interference removed, gain adjusted, S
TC adjustment (sea surface reflection removal), FTC (rain and snow reflection removal),
If it is related to image quality improvement of a display screen such as EXP (highlighted display), this control is started from the video signal of the next quadrant after completion of writing of the video signal of the quadrant currently being written to the data memory 19. .

For example, when the processor 10 receives a tuning control command during the writing of the video signal of the first quadrant to the data memory 19, the processor 10 writes the video signal of the first quadrant to the data memory 19. Wait for it to finish,
The instructed tuning control is executed by changing the control voltage supplied to the local oscillator 16.

On the other hand, the processor 1 of the sensor unit 1
0 indicates one screen being processed if the control command received from the personal computer 2 is a change in the radar mode (head-up, course-up, north-up) involving a change in the entire display screen, or a change in the image size. After the video signal of the last quadrant is written into the data memory 19, the control instructed from the first quadrant of the next screen is started. As described above, the control command relating to the image quality improvement is executed from the next quadrant being processed, whereby the display screen can follow the image quality improvement processing more easily.

Other types of control commands may include transmission trigger delay, bow adjustment, transmission on, transmission off, change in transmission pulse width, change in transfer rate (baud rate), and the like.

As described above, coordinate conversion of video signals, data transfer, update of the display screen, and start of control relating to image quality improvement are performed in units of each quadrant constituting the (X, Y) display screen. Accordingly, there is an advantage that a video signal for one screen can be processed by using the existing processing function prepared for processing the orthogonal two-dimensional screen as it is.

A marker superimposed on the video signal and displayed,
Various messages including symbols such as symbols and alphanumeric characters are created not by the sensor unit 1 but by the CPU 2a of the personal computer 2. The CPU 2a creates various necessary display data by executing a dedicated drawing program, and writes these into the screen memory 2d. The video signal and display data written in the screen memory 2d are read out under the control of the display unit 2e and displayed on the display panel 2b.

The configuration for processing a video signal in units of one quadrant has been described above. However, if necessary, each quadrant may be further divided into a plurality of equal parts, and coordinate conversion, data transfer, and updating of the display screen may be performed in the subdivided units.

Further, as the transfer mode of the video signal, the transfer mode for each quadrant and the transfer mode for each screen described above can be selected by a control command from the personal computer 2.

[0028]

As described in detail above, signal processing by the signal processing unit of the sensor unit, data transmission by the data transmission unit, and updating of the display screen by the display / control unit are synchronized with the rotation scanning by the rotation scanning unit. Since the configuration is executed for each quadrant of the orthogonal two-dimensional coordinate system, the update speed of the display screen is improved, the movement of the reflecting object in the display screen is smoothed, and the image quality is improved.

Also, since the image signal for one screen is transferred in four times for each quadrant instead of being transferred all at once, the transfer period of the data transfer path is smoothed and relatively reduced. A low-speed serial transmission line can be used, and the entire radar apparatus becomes economical.

Further, since the image signal for one screen is divided and transferred four times for each quadrant instead of transferring all at once, the storage capacity of the data memory 19 of the sensor unit 1 is two minutes. Two quadrants of one is sufficient, which makes it more economical.

Further, according to a preferred embodiment of the present invention, the signal processing section of the sensor section performs the processing of the control command transmitted from the display / control section relating to the improvement of the image quality of the video signal. Since the configuration is started from the video signal of the quadrant next to the quadrant, the responsiveness of the display screen to the image quality improvement operation of the display screen can be improved, and the image quality can be improved.

According to a preferred embodiment of the radar device of the present invention, a marker, a symbol, or the like, which is displayed while being superimposed on a video signal,
Since the display processing unit that draws display data such as numerical values is provided in the display / control unit that is composed of a general-purpose personal computer with high cost performance, the load on the sensor unit is further reduced, and the radar device as a whole Simplification, miniaturization, and cost reduction are realized.

[Brief description of the drawings]

FIG. 1 is a functional block diagram illustrating a configuration of a radar apparatus according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram for explaining an improvement in the update speed of a display screen by the radar apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor part 2 Personal computer 2a CPU 2b Display panel 3 Serial transmission line of control data 4 Serial transmission line of video signal 10 Processor 19 Data memory 20 Coordinate converter

Claims (4)

[Claims] A transmitting / receiving unit for transmitting a radio wave and receiving a reflected wave thereof as a received signal; a rotation scanning unit for rotating a direction of transmitting / receiving the radio wave of the transmitting / receiving unit; A signal processing unit for generating an image signal by performing / D conversion and performing coordinate conversion from a polar coordinate system to an orthogonal two-dimensional coordinate system; and a data transmission unit for transmitting the image signal generated by the signal processing unit to a serial transmission path. A sensor unit that receives the image signal from the sensor unit through the serial transmission path and displays the image signal, and a control command transmission unit that transmits a control command to the sensor unit via the transmission path. The signal processing by the signal processing unit of the sensor unit, the transmission of the image signal by the data transmission unit, and the display of the image display by the display / control unit are performed by the rotation scanning unit. Radar apparatus characterized in that it is performed for each quadrant of the orthogonal two-dimensional coordinate system in synchronization with the rotational scanning. 2. The image processing apparatus according to claim 1, wherein, among the control commands transmitted from the display / control unit, those related to image quality improvement of an image signal are started from an image signal in a quadrant next to the quadrant being processed. Radar equipment. 3. The display control unit according to claim 1, wherein the display / control unit includes a drawing processing unit that draws display data such as a marker, a symbol, and a numerical value that are displayed by being superimposed on the image signal. A radar device characterized by the above-mentioned. 4. A transmitting and receiving unit for transmitting a radio wave and receiving a reflected wave as a received signal, a rotation scanning unit for rotating the transmitting and receiving direction of the radio wave of the transmitting and receiving unit, and converting the received signal of the transmitting and receiving unit into a digital signal. A signal processing unit for generating an image signal by performing / D conversion and performing coordinate conversion from a polar coordinate system to an orthogonal two-dimensional coordinate system; and a data transmission unit for transmitting the image signal generated by the signal processing unit to a serial transmission path. A sensor unit that receives the image signal from the sensor unit through the serial transmission path and displays the image signal, and a control command transmission unit that transmits a control command to the sensor unit via the transmission path. The signal processing by the signal processing unit of the sensor unit, the transmission of the image signal by the data transmission unit, and the display of the image display by the display / control unit are performed by the rotation scanning unit. In synchronism with the rotation scan (360 / n) ° (n is an integer of 2 or more) radar apparatus which comprises carrying out each angular range.