JPS62177468A - Radar equipment for marine vessel - Google Patents

Abstract

PURPOSE:To obtain a high-reliability radar image by putting the 1st and 2nd radar antenna is partial charge of individual azimuth angle direction respectively. CONSTITUTION:The 1st and 2nd radar antenna driving parts 14A and 14B drive an rotate the 1st and the 2nd radar antennas 12A and 12B synchronously with each other by an antenna synchronizing control part 4. The azimuth angle ranges of target detection are assigned to the antennas 12A and 12B so that the azimuth angle range in front of a bow is assigned to the antenna 12A mounted at the bow part and the azimuth angle range behind a stern is assigned to the antenna 12B mounted at the stern part. When the antennas 12A and 12B are within the bow-directional azimuth angle range, a microwave switching mechanism 8 is switched to the size of the antenna 12A and when the antennas 12A and 12B rotate into the azimuth angle range behind the stern, the mechanism 8 is switched to the side of the antenna 12B. Even if there is an on-ship structure which reflects a radio wave and generates a virtual image between the bow and stern, the azimuth angle ranges are set properly so as to evade the structure and removed the virtual image, thereby improving the reliability to a radar image.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a marine radar system, and more particularly to a marine radar system equipped with two radar antennas for target object detection.

[Conventional technology]

Generally, in a marine radar system, a support such as a radar mast is installed at a predetermined position on the ship's hull (for example, at the stern).
Many systems are used in which a radar antenna mechanism comprising a radar antenna and an antenna drive unit for driving the radar antenna is installed at a predetermined height of the support.

In this method, while the antenna is rotated at a predetermined speed by an antenna drive unit, radar radio waves are transmitted and received by a separately equipped transceiver through the antenna, and the target object is detected on a display device such as a cathode ray tube. It is designed to display images.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional technology, the vertical beam width of the radar transmission wave is set relatively wide (for example, 25 degrees) in consideration of the ship's rolling, etc., so a part of the transmission wave is The waves are reflected by structures (such as tanker tanks, cranes, bridges, etc.) in a direction unrelated to the measurement detection direction, and this reflected wave detects a target in a direction that is not originally the detection target, making it appear as if the measurement detection The target object is displayed as if it existed in the direction. Because a so-called false image is projected on the display,
It has often been pointed out that there is a problem in that the reliability of the radar image is significantly reduced, such as when an operator misidentifies the false image as a real target.

In addition, to solve the above-mentioned problems, it is possible to install the antenna mechanism higher, but in this case, it will be difficult to secure visibility to the close range of the ship, so the height of the antenna mechanism should be set at a specified height. There was a situation where it was limited.

Furthermore, to address the above-mentioned disadvantages, a method has been proposed in which a radio wave absorber is pasted on structures to prevent reflection and scattering of radar waves, but in this method, the radio wave absorber itself is expensive. Therefore, large ships with the above-mentioned disadvantages are particularly expensive, and absorption efficiency for radio waves other than those incident vertically decreases significantly, making it impractical.

[Purpose of the invention]

The present invention improves the disadvantages of the prior art and almost completely eliminates false images caused by structures on board the ship without using any particularly complex signal processing techniques and with a simple configuration. It is an object of the present invention to provide a marine radar device that can obtain radar images with higher reliability.

Measures for Solving Problem c] Therefore, the present invention provides a first radar antenna that is installed in the bow portion and is responsible for detecting a target object in a first azimuth range in front of the bow; The first rotary drive
a second radar antenna that is installed in the stern portion and is responsible for detecting targets in a second azimuth angle range behind the stern; and a second radar antenna drive that rotationally drives the second radar antenna. and an antenna synchronization control unit that synchronizes the rotation of each of these radar antenna drive units, wherein the target object detection direction of each of the radar antennas is in the first azimuth range or the second azimuth range. a microwave switching mechanism that switches the microwave transmission/reception path to the first radar antenna side or the second radar antenna side in response to the
or a transceiver that transmits and receives target detection microwaves to and from the second radar antenna, processes the received waves, and outputs target detection information; and an image display unit that continuously displays radar images in the second azimuth range,
This aims to achieve the above objective.

[For production]

The first and second radar antenna drive sections rotate the first and second radar antennas, respectively, while being synchronized with each other by the antenna synchronization control section. The first of these
and a second radar antenna are each assigned an azimuth angle range for target detection, and the first radar antenna installed at the bow section is assigned the first azimuth range in front of the bow, and the azimuth range at the stern. The second radar antennas mounted on the sections are each responsible for a second azimuth range aft of I'Ji>tail.

When these first and second radar antennas are in the first azimuth angle range, the microwave transmission/reception path of the microwave switching mechanism is switched to the first radar antenna side. Therefore, the transceiver transmits microwaves for target detection to the first radar antenna, and the first radar antenna transmits reflected waves from the received target to the transceiver. The image display section displays a radar image based on the target object detection information sent from the transceiver.

On the other hand, when the rotation of the first and second radar antennas progresses to a second azimuth range, the microwave switching mechanism switches the microwave transmission/reception path to the second radar antenna side. . Therefore, the transceiver now performs a target object detection operation via the second radar antenna, and causes the image display section to display a radar image.

Such operations are repeated at predetermined timings as the first and second radar antennas rotate.

Therefore, the image display section continuously displays the radar image of the first azimuth angle range applied to the first radar antenna and the radar image of the second azimuth angle range applied to the second radar antenna in approximately real time. be done.

Therefore, (If) even if there is a structure on the own ship between the bow and stern part that reflects target object detection radio waves and generates a false image, there is a structure that becomes an obstacle. By appropriately setting the first and second azimuth angle ranges to avoid objects, etc., it is possible to almost completely eliminate false images on the radar image caused by the structures, etc.
The reliability of radar images can be increased. Furthermore, since switching is performed at the microwave stage, only one transmitter/receiver is required, which simplifies the overall configuration.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

First, in FIG. 1, the marine radar device is installed at a predetermined position on the bow of the ship, and is located in a first azimuth range θA in front of the bow.
(See Fig. 3 (1)) A first radar antenna structure 2A responsible for target detection (see Fig. 3 (1)) and a second azimuth angle range θ, l installed at a predetermined position in the stern section (Fig. 3 ( It is equipped with two antenna mechanisms consisting of a second radar antenna mechanism 2B responsible for target detection (see 1)), and a second radar antenna mechanism 2B responsible for detecting the target object (see 1). An antenna synchronization control section 4 is provided that mutually synchronizes the rotational drive of the second radar antenna mechanisms 2A and 2B.

Furthermore, this device includes a single transmitter/receiver a6 that transmits and receives microwaves for target object detection, processes the received microwaves, and outputs predetermined target object detection information, and a single transmitter/receiver a6 that transmits and receives microwaves for target detection. a microwave switching mechanism 8 that automatically switches at a timing and outputs the output to the first or second radar antenna mechanism 2 or 2B; Second
and an image display section 10 that continuously displays radar images in the azimuth angle ranges θ and θ8.

This will be explained more specifically.

The first radar antenna mechanism 2A includes a first radar antenna side 2Δ that transmits and receives microwaves while rotating;
The first radar antenna driving section 14A rotates the first radar antenna 12A. The first radar antenna driving section 14A further includes a first motor 16A that rotates the first radar antenna 12A, and a first synchro oscillator 18A that operates in conjunction with the first motor 16A. It is configured. The first synchro oscillator 18A constantly detects the rotation angle of the first radar antenna 12A, and
An analog angle signal RA corresponding to the rotation angle of the radar antenna 12A is sent to the antenna synchronization control unit 4. The signal is output to the microwave switching mechanism 8 and the image display section 10, respectively.

Further, the second radar antenna mechanism 2B includes the first radar antenna mechanism 2B.
Similarly to the radar antenna mechanism 2A, it consists of a second radar antenna 12B and a second radar antenna drive section 14B. Furthermore, this second radar antenna driving section 14
B is the second motor 16B and the second synchro oscillator 1
8B. The second synchro oscillator 18B is connected to the second radar antenna 12B.
An analog angle signal R8 corresponding to the rotation angle is output to the antenna synchronization control section 4.

Furthermore, the antenna synchronization control section 4 compares the angle signals RA and Rs output from the first and second synchro oscillators 18A and 18B, respectively, and outputs a correction control signal depending on the result. It is comprised of a control transformer 20 and a servo amplifier 22 that amplifies a control signal output from the synchro control transformer 20 and causes the rotation of the second motor 16B to be synchronously controlled by the first motor 16A.

Specifically, the synchro control transformer 20 has a function of comparing both angle signals R,,R, and outputting the difference as a correction control signal (voltage) to the servo amplifier 22 only when they do not match. have. The servo amplifier 22 amplifies the manually applied voltage and applies it to the rotational speed control means of the second motor 16B. Therefore, the second motor 1
Motor 6B increases or decreases its speed according to the amount of voltage input, and rotates in a predetermined direction in synchronization with the first motor 16A within a very short time. That is,
The above comparison control is repeated at predetermined timing until the rotations of the first motor 16A and the second motor 16B are almost completely synchronized and the output of the servo amplifier 22 becomes zero.

On the other hand, the transmission and reception of microwaves for target object detection is carried out by the transmission and reception stage 6. Microwave switching mechanism 8. and the first and second radar antennas 12A and 12B.

Here, the microwave switching mechanism 8 will be explained.

The microwave switching mechanism 8 includes a circulator section 24 that switches the microwave transmission/reception path to the first or second radar antenna 12A or 12B side, a switching control section 26 that controls the switching operation of the circulator section 24, and a switching control section 26 that controls the switching operation of the circulator section 24. It is constituted by a reference value setting section 28 that sets the reference value of the first and second azimuth angle ranges θ and θ8 for the switching control section 26. In this embodiment, θ, , θ in this reference value setting section 28 are each set to 1806 (third
Figure (1) (see 21). In other words, the first. As shown in Figure 3 (1), the second azimuth angle range θ, θ8 is a structure on the hull that obstructs the microwaves for target detection and causes the microwaves to be reflected in a direction other than the intended direction. 30. ...
, 30, it is determined that these structures 30 are mutually avoided.

Further, as shown in the figure, the circulator section 24 includes first and second circulators 32A and 32B as microwave transmission and reception paths, and the circulators 32A and 32B.
The power supply circuit 34 controls the reversal switching of the circulation path of the circulator 2B, and each circulator 32A, 32B
Each of the excitation coils 32Aa and 32Ba is connected to the power supply circuit 3.
From 4 onwards, an excitation current 2 is applied. Furthermore, the opening end (3) of the first circulator 32A is connected to the first circulator 32A.
The open end (2) reaches the receiving section 6A of the transmitter/receiver 8!6 and the closed end (2) of the second circulator 32B. Also, the first
The open ends (2) and (2) of the circulator 32A are connected to the open end (2) of the second circulator 32B and the transmitter 6B of the transceiver 6, respectively. Further, the open end (2) of the second circulator 32B is connected to the second radar antenna 12B, as shown in FIG.

The switching control section 26 then sends a setting signal θ, (θ, to θ,
2), and if the angle signal RA is within the setting signal θ (that is, within the first azimuth angle range θ4), in this embodiment, the predetermined “low” level control signal S is turned on. circuit 3
It is configured to output to 4. As a result, in this embodiment, the exciting current I flows through each exciting coil 32Aa, 32Ba in the direction shown by the solid line in the figure, and the path of the microwave circulating through the first and second circulators 32A, 32B is shown by the solid line. As shown in [■−■−■−■−■] and [■
−■−■−■].

In other words, the microwave from the transmitter 6B of the transceiver 6 is
The light passes through the open end (2) of the first circulator 32A and is transmitted to the first radar antenna 12A. Also,
On the other hand, the received wave from the first radar antenna 12A passes sequentially through the open ends (■-■) of the first circulator 32A and is output to the receiving section 6A of the transmitter/receiver a6. In this case, the second radar antenna 12B and the transceiver 6 are almost isolated from each other in terms of microwaves.

On the other hand, the first. The rotation of the second radar antennas 12A and 12B progresses, and the angle signal R4 becomes the setting signal θ.

(in other words, within the second azimuth range θ8), the switching control section 26 outputs a predetermined "high" level control signal S to the power supply circuit 34.

As a result, this power supply circuit 34 is connected to each excitation coil 32A.
1.a and 32Ba in the direction shown by the dotted line to reverse the magnetic fields. The circulation paths of the second circulators 32A and 32B are [■-■-■→■-
■〕, [■−■−■−■].

In other words, the microwaves from the transmitter 6B of the transceiver 6 are transmitted to the open ends (1), (2) of the first circulator 32A and the second circulator 3, as shown by the dotted line in FIG.
The signal propagates sequentially through the open ends (2) and (2) of the antenna 2B and is output to the second radar antenna 12B. On the contrary, the received wave from the second radar antenna 12B is outputted to the receiving section 6A via the second circulators (2) and (2). In this case, the first radar antenna 12A and the transceiver 6 are almost isolated from each other in terms of microwaves.

On the other hand, as described above, the transceiver 6 includes a transmitting section 6B that forms and outputs microwaves for detecting a target object, and a receiving section 6A that receives reflected waves from the target object.

Of these, the transmitting section 6B has a function of outputting a trigger signal TP to the image display section 10 every time transmission, and the receiving section 6A has a function of processing the received wave and outputting an image signal VD to the image display section 10. ing.

Furthermore, the image display section 10 is constructed using the PPr method in this embodiment.

Next, the overall operation of this embodiment will be explained.

First, when the device is driven, the first. The rotation of the second radar antennas 12A, 12B is started, and as described above, the antenna synchronization control section 4 controls the first... A synchronized operation with respect to the rotation of the second radar antennas 12A, 12B is performed. This action is performed immediately and automatically even when the antennas are out of synchronization due to weather conditions, etc., and as a result, each radar antenna 12A, 12B rotates synchronously at a predetermined speed while maintaining an almost stable state. It turns out.

And the first. Second radar antenna L2A.

12B is rotating within the first azimuth angle range θ in front of the bow, for example, as described above, the microwave switching mechanism 8 causes the transceiver 6 and the first radar antenna 12A to switch between microwaves. wave-likely coupled. Therefore, the microwave output from the transmitting section 6B of the transceiver 6 is radiated into the atmosphere via the circulator section 24 and the first radar antenna 12A, and is used for a predetermined target object detection operation. On the contrary, the reflected wave from the target object is propagated to the receiving section 6A of the transceiver 6 via a path opposite to that described above.

The received wave is then subjected to signal processing in the receiving section 6A, and as a result, an image signal VD is output to the image display section 10. Therefore, in the image display section 10, the input image signal VD
Radar images based on the PPI method are displayed in approximately real time.

On the contrary, the first. Second radar antenna 12A.

12B continues to rotate and the target object detection direction enters the second azimuth angle range θ behind the stern, the circulation path of the circulator section 24 of the microwave switching mechanism 8 is automatically changed as described above. And it can be reversed within an instant. Therefore, this time, the transmitter/receiver a6 and the second radar antenna 12B are microwave-coupled, and the microwaves for target detection are transmitted and received in the same manner as the first radar antenna 12A described above. It will be done. As a result, the image display unit 10 displays a radar image in the second azimuth angle range θ8 related to the second radar antenna 12B.

Furthermore, the first. Second radar antenna 12A.

12B continues to rotate and enters the first azimuth range θ again, the circulator section 24 is reversed again and returns to its original position, resulting in the first Radar images with an azimuth angle range of θ are obtained.

In this way, in this embodiment, the structures 30. ..., so as not to be influenced by 30. second azimuth angle range θ; .

Since θ8 is assigned to each part, each radar antenna 12A, 12B does not have to detect an azimuth range where microwaves are blocked by each structure 30, and as a result, the image display unit 10 30 is almost completely eliminated. Therefore, a valuable advantage is obtained in that the reliability of the radar screen is significantly increased. Furthermore, in the prior art, radar radio waves may exist in a blind spot in the opposite direction due to a radar mast or the like, but in this embodiment, such a blind spot can also be eliminated.

In addition, in the configuration of this embodiment, the transmitter/receiver 6, the image display unit 10, etc. can be installed using existing ones,
In addition, although the microwave switching mechanism 8 requires particularly complex signal processing, since the switching operation is performed at the microwave stage, only one transmitter/receiver is required. has been significantly simplified.

On the other hand, it is no longer necessary to attach expensive radio wave absorbers to structures onboard the ship as in the conventional example, and an increase in equipment costs can also be eliminated.

Furthermore, as described above, each radar antenna 12A.

12B emits almost no microwaves in the azimuth angle range other than each share, so the signal source for target detection is suppressed to the minimum necessary one, thereby reducing overall crosstalk and noise radio wave contamination. etc. are becoming fewer.

In addition, the microwave generating means such as the magnetron in the transmitting section of the transmitter/receiver is not turned on or off depending on the rotation angle of the radar antenna, but is kept in operation, and the microwave source is apparently always kept at one source as described above. are doing.

Therefore, this embodiment has the advantage of reducing the load on f+ when the microwave generating means is turned on and off, thereby increasing its durability and stabilizing its operation.

In the above embodiment, the first and second azimuth angle ranges θ7 and θ8 were each 180', but the present invention is not necessarily limited to this, and may be changed depending on the structural convenience of the ship. For example, θA=280°, θB=8
0'), or the reference value setting unit 28 may be configured to be able to change θ from the outside to facilitate its adjustment. Further, the image display section 10 may be configured to include a memory means for storing image signals, etc., and obtain a radar image using a raster scan method. Furthermore, in the embodiment described above, the second radar antenna drive section 14B is synchronized with the first radar antenna drive section 14A, but it may be configured to perform synchronous control in the opposite manner. Furthermore, it is also possible to further improve the image quality by equipping each radar antenna 12A, 12B with a radome in consideration of the influence of wind, and performing synchronous rotation more precisely. Furthermore, the connection and control method of the circulator section is not necessarily limited to the above-mentioned method.

On the other hand, in the embodiment described above, the first and second radar antennas 12A and 12B are installed at the bow and stern, but they may be installed at other appropriate positions on the hull, and there may be three radar antennas, for example. A configuration in which both are used simultaneously is also possible.

Further, the above-mentioned embodiments are applicable not only to ships but also to land systems such as port radars. For example, a case can be assumed in which a false image is generated due to the reflection of radar waves from a bridge such as the Honshu Bridge connecting Honshu and Shikoku. In such a case, two designated areas on both sides of the bridge should be used.
It is also possible to apply the present invention to certain locations, transmit images from land to a ship passing under the bridge, and obtain undisguised radar images of both sides of the bridge on the ship.

〔Effect of the invention〕

Since the present invention is configured and functions as described above, according to this, when there is a structure on the own ship that is an obstacle to radar radio waves having a predetermined vertical beam width between the bow and the stern, However, the first and second azimuth angle ranges are appropriately determined to avoid the structure, and
1st. By synchronizing the rotation of the second radar antenna and switching to each radar antenna at the microwave stage, the configuration is extremely simple, requiring only one transmitter/receiver without any complicated signal processing. It is possible to almost completely prevent the occurrence of false images caused by structures, which significantly improves the reliability of radar images and further enhances the functionality of radar equipment.Furthermore, it is possible to use existing radar equipment. It is possible to provide an excellent marine radar device that can be expanded and installed, thereby reducing equipment costs.

[Brief explanation of drawings]

Fig. 1 is a functional block diagram showing one embodiment of the present invention;
The figure is a block diagram showing the details of Fig. 1, Fig. 3 (1) is an explanatory diagram showing the positional relationship of the first and second radar antennas, etc., and Fig. 3 (2) is the first and second azimuth. It is an explanatory view explaining a corner range. 4... Antenna synchronization control unit, 6... Transmitter/receiver, 8... Microwave switching mechanism, 10...
...Image display section, 12A, 12B...1st
．． Second radar antenna, 14△, 14B...
1st. Second radar antenna drive unit, 32Δ, 32B・
...First as a transmission/reception path for microwaves. Second circulator. Patent applicant: Tokyo Co., Ltd. Keiki No. 3 C1> (2)

Claims (1)

[Claims] (1) a first radar antenna installed at the bow of the ship and responsible for detecting targets in a first azimuth range in front of the bow;
a first radar antenna drive unit that rotationally drives a radar antenna; a second radar antenna that is installed in the stern portion and is responsible for detecting a target in a second azimuth angle range behind the stern; A second radar antenna drive section that rotates and an antenna synchronization control section that synchronizes the rotation of each of these radar antenna drive sections, and the target object detection direction of each of the radar antennas is within the first azimuth angle range. or a microwave switching mechanism that switches the microwave transmission/reception path to the first radar antenna side or the second radar antenna side depending on whether the microwave is in the second azimuth range; a transceiver that transmits and receives target detection microwaves to and from the first or second radar antenna, processes the received waves, and outputs target detection information;
A marine radar device comprising: an image display unit that continuously displays radar images in the first and second azimuth angle ranges based on target detection information from the transceiver.