JPS6288976A - Dual antenna radar for ship - Google Patents

Abstract

PURPOSE:To shorten a radar video update time by transmitting two kinds of different-frequency pulse groups by radar antennas dedicated to their frequencies and composing the image of radar videos of received signals from two receivers which receive the signal corresponding to the frequencies. CONSTITUTION:A diplexer 2 classifies two kinds of pulse groups of frequencies f1 and f2 generated by an amplification type transmitter 4a and supplies the pulse group of frequency f1 to a radar antenna 1a and the pulse group of frequency f2 to a radar antenna 1b. The antennas 1a and 1b are rotated by a rotary driving device 3 while having a 180 deg. phase difference and transmit the pulse groups of frequencies f1 and f2 successively. Then, a receiver 4b receives a signal Rf1 and a receiver 4c receives a signal Rf2 corresponding to the antennas 1a and 1b and their video signals Vf1 and Vf2 are adjusted by a following coupler 6 to the same phase and put together into a composite video signal, which is displayed on a PPI 7. Thus, the radar video signal is updated in a time which is a half as long as before.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a borehole antenna radar suitable for use in navigation of ships.

[Conventional technology]

Conventional marine radar has a radar antenna rotation angle of approximately 2
The time required for one rotation of the radar antenna, that is, the time required for one rotation of the sweep line, is relatively long at about 3 seconds. For this reason, in the case of a motor heart sailing at high speed, or a ship sailing in a curve or turning even at low speed, the reflected light received by the radar is
It is difficult to track the ship because the numbers are scattered.

Therefore, in order to eliminate the above problems, conventionally,
Some have two independent radars installed on the radar mast.

[Problem that the invention seeks to solve]

However, when trying to use two independent radars as described above, the limited space on the radar mast is accompanied by limitations in terms of equipment, and it is difficult to identify small ships from the clutter caused by the shattered waves. It is very difficult to do so.

The present invention has been made in view of the above points, and its purpose is to be able to scan a sweep line in approximately half the time compared to the conventional single scanner, and to scan a sweep line using two independent scanners. It is possible to avoid equipment problems caused by the limited space on the radar mast that occurs when using a single radar, and furthermore, by using two types of 9-Russ groups with different frequencies, it is possible to avoid waves due to the difference in frequency. An object of the present invention is to provide a dual antenna radar for ships that can improve identification of small ships by reducing di-clutter using reflected waves.

[Means for solving problems]

Therefore, the dual antenna radar for ships of the present invention includes an antenna unit that is equipped with two radar antennas back to back on one rotary drive device and rotates simultaneously as a unit, and two radar antennas with different frequencies. a transmitter that generates the above two types of pulse groups 1r outputted from this transmitter: a rotary radio that supplies the two radar antennas and receives and outputs the received signals; A guiplexer that sorts and sorts pulses and supplies only a group of dedicated frequency pulses to each radar antenna, two receivers that receive signals corresponding to the frequencies from the radar antenna, and the frequencies output from these receivers. This configuration includes a radar indicator that synthesizes and displays radar videos based on different received signals.

[Effect]

Therefore, according to the dual antenna J-da for ships as described above, the received signals from each radar antenna are simultaneously displayed in the respective areas obtained by dividing the radar screen into two, so that it is different from the conventional method. Compared to the radar video that is updated every time the radar antenna rotates 36 degrees, the radar video is updated every time each radar antenna rotates 180 degrees, so the radar video update time is shortened to the conventional A. Therefore, the ability to track other ships is doubled compared to the conventional method. Also,
By making the frequencies handled by the two antennas slightly different, the signal, signal, and signal are slightly different, and by comparing the videos from the Oka antenna in the combiner, the signal, signal, and signal can be slightly reduced.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 shows the functional features of a dual antenna radar for ships, and FIG. 2 shows the equipment configuration of the radar.

In the figure, lh and lb are radar antennas, which are combined back to back to have a rotational phase of 18,000 and are mounted on the rotation drive device 3 together with the guiplexer 2. This rotary drive device fR,3 has a built-in rotary joint 3a. The Guiplexer 2 is 2
Two types of radar antennas Ja+Jb with different frequencies
The radar airborne -ml a#1 is classified into the f-schiff group.
It has the function of supplying only the 1,000-Russ group of dedicated frequencies corresponding to b.

4 is a radar transceiver, which has different frequencies fI
, f2 (however, -m225〈10%) of the amplified transmitter 4a that alternately generates two types of pulse groups, and the received signals fl -f from the radar antennas 1* and lb. It is comprised of a first receiver 4 and a second receiver 4c that receive only the dedicated reception signal f1t or f2 and output it as a video signal. 5 is each receiver 9 machine 4b, 4
This is a radar indicator that combines and displays the radar video signals output from (Plan Po5
tion Indlcator) 7 and many other components.

Next, the operation of the dual antenna radar for ships according to the above embodiment will be explained. Frequency f* from amplification amount transmitter 1a
When two types of pulse groups with different −fx are generated alternately,
These pulse groups are supplied to the guiplexer 2 through the rotary resolution India 3a. Here, the guiplexer 2 receives the frequency 7 which is input via the rotary joint 3a.
)A. seed. 2, 27 groups are sorted and the pulse group of frequency 11 is sent to the radar antenna 11L, and the pulse group of frequency f! and the arm group are respectively supplied to the radar antenna 1b. At this time, both radar antennas 1&+1b are rotated by the rotary drive device 3 with a rotational phase of 180', and the guiplexer 2 outputs A? of the corresponding frequency f1-fz. When it receives a group of waves, it transmits them sequentially.

After that, the frequency f is set at each radar antenna 1m and 1b.
When receiving the received signal Rf* h Rfz of I, fx,
Of these received signals Rfx +Rfz, the first receiver 4b receives the received signal Rft through the guiplexer 2 and the rotary joint 3a, and the second receiver 4C receives the received signal Rf2, and is output as a video signal Vfx *Vfz. Then, these video signals Vft * Vft are phase-adjusted and matched in the subsequent combiner 6 to obtain a composite video signal, which is transmitted to the PPI
Display on F. Therefore, since the radar antenna 1a and the radar antenna 1b rotate with a deviation of 1800 degrees, the PPI,
Two sweep lines are rotated on ib with a 180° shift, and the radar video signal is updated every time the center lines 1a and lb rotate nine times. That is, the radar video update time is l
It is shortened to h. Furthermore, since the g-clutter differs slightly between the frequencies fx and fz, by comparing and synthesizing the g-clutter of both frequencies, it was possible to reduce the g-clutter and improve the job-specific ability of small ships. Effects] As detailed above, the borehole antenna radar for ships of the present invention has the following effects.

(By doubling the repetition frequency of the transmitter, the radar video signal can be updated in the conventional time A without reducing the number of pulse hits per revolution of the radar antenna (the data rate can be doubled) Therefore, the ability to track other ships will be greatly improved, making it effective for unmanned intelligent ships.

(2) Furthermore, since only one rotating and driving device is required, it can be used even in the limited space on the radar mast.

(3) Furthermore, compared to the case where two independent radars are used, there is no need for rotational synchronization or coordinate correction due to positional differences, and the circuit configuration can be simplified.

(41) Also, since radio waves are emitted from a single point compared to when two independent radars are used, the azimuth and distance of other ships, etc. at close range can be more accurately captured.

(5) Also, since the di-clutter differs due to the difference in frequency, by overlapping and comparing the di-clutter received by both radar antennas, di-clutter can be reduced and the identification ability of small ships can be improved. be able to.

[Brief explanation of drawings]

1 and 2 are for explaining an embodiment of the borehole antenna radar for ships according to the present invention. FIG. 1 is a functional block diagram, and FIG. 2 is a schematic diagram of the equipment configuration of the radar of the present invention. FIG. Jm...Radar antenna, 1b...Radar antenna, 2
90. Guiplexer, 3... Rotary drive device d, 3
a...Rotary joint, 4...Radar transmission/reception f
e +V %”...Amplification type transmitter, 4b...1st
Receiver<S machine, 4C...Second receiver, 5...Radar indicator, 5m...Coupler, 5b ・-PPI (P
lan Po5ition Indicator). Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2

Claims (1)

[Claims] An antenna unit that rotates two radar antennas back to back on one rotary drive device at the same time, a transmitter that generates two types of pulse groups with different frequencies, and the two types that are output from this transmitter. a rotary joint that supplies pulse groups to two radar antennas and receives and outputs received signals; and a rotary joint that classifies and selects the two types of pulse groups and supplies only pulse groups of a dedicated frequency to the corresponding radar antennas. The present invention is characterized by comprising a diplexer, two receivers that receive signals according to reception frequencies from the radar antenna, and a radar indicator that synthesizes and displays video signals output from these receivers. Dual antenna radar for ships.