JPS58204380A - Radar device - Google Patents

Abstract

PURPOSE:To shorten remarkably the time required for catch and tracking, by fixing a beam in the direction of a detected target, obtaining an angle error signal by a monopulse difference channel, and tracking the target by a pencil beam. CONSTITUTION:When a signal processor 6 detects a target signal as distance information, the processor 6 displays it on an indicator 7 and simultaneously sends out a target detecting signal (c) to an information processor 8. As a result, a scanning angle command signal (a) is held to an angle signal in the direction where a fan beam detects a target. The signal processor 6 detects magnitude and phase of a monopulse sum channel signal and a monopulse difference channel signal, and transmits an angle error signal (d) to the information processor 8. In this state, the fan beam is switched to a pencil beam, and simultaneously, an angle direction corresponding to the angle error signal (d) is calculated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radar device that performs beam scanning electronically, and includes a beam scanning controller for original beam scanning, a phase data storage circuit for fan beam formation, an adder, and a switch. The fan beam is scanned at high speed by driving and controlling the phase shifter of the phased array antenna, and when a signal processor detects a target, the beam is fixed in that direction, and the fan beam is Using a monopulse difference channel in the wide beam width direction, an angular error signal indicating the direction of the target is obtained, and the information processor switches the fan beam to a pencil beam to direct it toward the target and track the target. The present invention aims to provide a radar device that searches for objects from a wide angular range and significantly shortens the time required to capture and track objects.

A conventional radar device using a 7-aided array antenna or a mechanical scanning antenna has the disadvantage that it takes a long time to scan the entire angular range because it scans a wide angular range with a pennular beam. In the case of mechanically scanned antennas,
It is difficult to change the antenna beam shape, and
Even if the signal processor detects a target, it cannot instantly fix the beam in the target direction due to the inertia of the antenna, so it scans the antenna beam within a narrow angular range in the target direction.

Because it uses means to capture and track the target, it takes even longer.

In general, during close combat of fighter aircraft, radar equipment for fighter aircraft is required to detect, capture, and track targets at relatively short distances in a short time rather than detecting target sounds at long distances. . Therefore, the length of time it takes to search and acquire a target will determine the ability of the two fighter aircraft to hit the target and their survivability.

This will reduce the performance of the conventional radar device 11LI/'i1 fighter aircraft, which takes a long time to acquire and track a target.

The present invention was made in order to eliminate such drawbacks in conventional radar equipment, and includes a phase data storage circuit, an adder, a switch, and a beam scanning device for original beam scanning. It is now possible to easily form a fan beam with a simple configuration that only requires setting up a When fixed, the signal processor extracts the error signal of the monopulse difference channel and transmits the angle signal in the wide beam width direction of the fan beam, so the information processor switches the fan beam to a pencil beam and directs it to the target direction. Therefore, it is an object of the present invention to provide a radar device that can significantly shorten the time required to search for, acquire, and track a target located at a relatively short distance by capturing and tracking the target.

The diagram below shows the conventional radar device and the radar device of this invention.
Describe the device. FIG. 1 is a diagram showing an example of the configuration of a conventional radar device, in which (11 is a controller, (2)
is a transmitter, (3I is a transmitter/receiver switch, (4) is a 7-aided array antenna, (5) is a receiver, (6) is a signal processor,
(7) is a display, (8) is fftI&processor, (91 is a beam scanning controller, ul is a phase shift amount calculation control circuit, (lυ
is a drive circuit, Σ is a monopulse sum channel, and Δ is a monopulse difference channel.

- F Since the configuration of the conventional radar device is as described above, the transmitter (2) transmits a pulsed transmission signal to the transmitter/receiver switch based on the radar transmission mode selected by the controller (1). +31 to the phased array antenna (4). The transmitted signal is radiated into space from the phased array antenna +41, reflected by the target, received again by the phased array antenna (4), and inputted to (5) after receiving it again through the transmitter/receiver switch (3).This received signal is amplified and mixed in the receiver (5) to become an intermediate frequency band signal, which is further amplified, filtered, converted to a digital signal, and sent to the signal processor +61.The signal processor (6) is a digital signal. Processing such as detection of the converted video signal is performed, and when it is judged as a signal, the information is sent to the display device (7) and displayed.The output of the signal processor 16+ is also sent to the information processor 18). Then, a target tracking command is given based on the target tracking command from the controller (1), and accurate distance measurement is performed.

Speed and angle information is extracted and displayed in symbols and numbers in instruction 6 (71).

On the other hand, when the information processor (8) sends a beam scanning angle command signal a to the phase shift calculation control circuit αG in the beam scanning controller (91) based on the coverage area and beam scanning pattern selected by the controller 141, The phase shift calculation control circuit a1 calculates the phase shift amount to be given to the phase shifters of a large number of antenna elements (not shown) constituting the phased array antenna, and outputs a phase shifter drive signal from the drive circuit [+11]. to drive and set the phase shifter of the antenna element.

As a result, the antenna main beam is often directed in the command angle opening direction.

In addition, in order to fire weapons such as missiles at a target from a long distance, the 9 Combat Horizontal Rator requires finding, capturing, and tracking the target at a long distance, but in this case, a high-gain pencil beam is used. Scanning at a relatively slow speed is advantageous because the data rate is higher and targets can be detected over longer distances. On the other hand, when fighter jets engage in close combat, the distance to the target is short, so they fire short-range weapons such as machine guns, so they are required to spot, capture, and track the target faster than the enemy. However, since conventional radars scan with a pencil beam, it takes a long time to scan a wide angular range. In close combat, the distance to the target is short, so the signal reflected from the target is strong enough.
Even if a fan beam with a reduced gain is used, sufficient target detection performance can be ensured. Since the angular range is expanded when a fan beam is used, the time required to scan a wide angular range is shorter than when a pencil beam is used.

Figure 2 fat shows the beam scanning system of a conventional radar device, and the time Tp required to scan the entire angular range with the pencil beam α9 is θAz: Horizontal scan angle range θ Anal: Vertical scan angle range ω : Beam scanning speed θBP: Beam width of the pencil beam, and the average time required to find the target is TP/
It is 2. Figure 2(b) shows the beam scanning method of the radar device based on the present invention, which scans the entire angular range of the fan beam αG and uses a monopulse difference channel to obtain an angular error signal, thereby directing the pencil beam strike in the target direction. The time TF required to point to the fan beam is θBF=beam width TM of the fan beam: the time required to obtain the angular error signal in the monopulse difference channel N: the ratio of the beam widths of the fan beam and the pencil beam N〒θBF108F. What is the average time it takes to discover a target?

p (Pashou TM).

As is clear from this equation, scanning with fan beam (2) can significantly shorten the time required to shift from target discovery to acquisition and tracking.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 3 is a diagram showing an embodiment of the present invention.

The feature of the present invention is that it has a simple configuration in which a phase data storage circuit 0, an adder α3, and a switch α- are installed in the beam scanning controller (9;) of the conventional rotator device shown in FIG. It is possible to easily form a fan beam, and when a target is found by scanning a wide angular range with the fan beam, the beam is fixed at °, and the monopulse difference channel is used to obtain the angular error signal d, and the direction to the target is determined. The point is that it is possible to direct the pencil beam to a target and track it in a short time.The phase data storage circuit ■ contains a large number of phase distributions on the antenna aperture plane necessary to form a fan beam. The phase shift amount calculation control circuit 0α is stored in correspondence with the antenna element of
Based on the beam scanning angle command signal a from the information processor +81, the amount of phase shift of each antenna element required to direct the beam in the commanded direction is calculated. Now, the controller t
When the short-range target automatic acquisition mode is selected in it, the information processing@fr tel receives the mode signal from the controller (1) and transmits the beam shape switching signal di beam scanning controller (9).
) is sent to the switch αO. A switch (141) receives the beam shape switching signal e and connects the phase shift amount calculation control circuit Ql and the adder port.

After the information processor (81) completes the connection of the switch α-, the beam scanning angle command signal a is sent to the phase shift amount calculation control circuit (l). The amount of phase shift of each antenna element required to do this is calculated and sent to the adder ■ for each antenna element.Adder 11
3 adds the phase shift amount of each antenna element from the phase shift amount calculation control circuit Ql and the phase data for fan beam formation sent from the phase data storage circuit α2 through the switch aS, corresponding to each antenna element, and drives the antenna element. Circuit I] 11. The drive circuit in drives and controls the phase shifter of an antenna element (not shown) of the phased array antenna (4). On the antenna aperture surface, a curved phase distribution for forming a fan beam is added and synthesized on a linear phase plane according to the beam directivity angle, so a fan beam is formed in the direction of the beam scanning angle. . The information processor (8) sequentially updates the beam scanning angle command signal a to change the beam directing angle in order to scan the fan beam over a wide angle range.

On the other hand, depending on the mode signal from the controller (1), the transmitter (
2) generates a pulse-shaped transmission signal and sends it to the transmission/reception switch (31
to the phased array antenna (4). The transmitted signal is radiated into a wide space as a fan beam from the phased array antenna (4), and when a target exists within the fan beam, it is reflected and received by the phased array antenna 14), and passes through the transmitter/receiver switch f31i again to the receiver. (5)
The signal is input to the signal processor (6) as a video signal that is amplified, mixed, and converted into a digital signal. The signal processing d+6+ detects the target signal from the thermal noise generated by the reception@(51) or the clutter reflected from the ground and received at the same time as the target signal.In the case of the pulse radar method, the received signal is detected by envelope detection. Since it has been
The magnitude of the amplitude of the pulsed signal and its delay time from the transmitted pulse are determined, and in the case of the pulsed-nhurra radar method, phase detection is performed, so the drag frequency information and the uncertain delay time from the transmitted pulse are determined. When the private signal is determined, the target signal C is sent to the information processor (81) and the target detection signal C is sent to the information processor (81). customary information salmon 6 (8
1 receives the target detection signal C from the signal processor (6),
While keeping the beam scanning angle command = qa at the angle signal in the direction in which the fan beam detected the target, the signal processor (
6) to perform signal processing of the monopulse difference channel. The signal processor +61 +d detects the magnitude and phase of the mono/curs sum channel signal and the mono/curs difference channel signal, and sends the angular error signal (1) to the information processor (8). When the angular error signal d is received, the beam shape switching signal e is sent to the switch I in the beam scanning controller (9) to switch the fan beam to the pencil beam and at the same time change the angular direction according to the angular error signal d. Calculate.

In order to direct the entire pencil beam in that direction, the beam scanning angle command signal a is sent to the phase shift calculation control circuit as angle information in the target direction. When the switch α core receives the beam shape switching signal C, it disconnects the phase data storage circuit side and connects it to the ground terminal, so the output from the switch α- to the adder u3 is always zero. Then, the output signal of the phase shift calculation control circuit C1 (I) is added to zero by the adder@, so that it directly passes through the drive circuit to drive and control the phase shifters of the many antenna elements of the phased array antenna.

Therefore, since the aperture phase distribution for fan beam formation is removed, the pencil beam becomes a normal pencil beam, and the pencil beam is directed toward the target by the beam scanning angle command signal a in the direction in which the target exists. The signal received by the pencil beam is subjected to monopulse processing by a receiver (5) and a signal processor (61), and an angular error signal d is sent to an information processor (81) for nI precise angle tracking. Information processing The device (8) detects the difference between this angle error signal d and the beam scanning angle command signal a, and updates the beam scanning angle command signal a so that this difference becomes zero, making it possible to capture and track the target. can.

As described above, according to the present invention, in a V-da system that electronically scans a beam, a simple configuration is possible by simply installing a phase data storage circuit, an adder, and a switch in a beam scanning controller. By switching the phase distribution of the antenna aperture and easily forming and scanning a fan beam,
It is possible to significantly shorten the time from searching for a target that exists at a short distance to capturing and tracking it.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of a conventional radar device, FIG. 2 is a diagram showing a conventional radar device @: and a heem seven eclipse method of a radar device based on this invention, and FIG. 3 is an example of an implementation based on this invention. It is a diagram showing the configuration of an example radar device, in which (1) is a controller, (2j is a transmitter, (3j is a transmitter/receiver switcher, (4) is a phased array antenna, (51 is a receiver, and (6) is a Signal processor, +7+B display, (81 is information processor, +91
is the beam scanning side
is a drive circuit, and the old one is a phase data storage circuit. 03 is an adder, 114 is a switch, (1 is a pencil beam, ul is a fan beam, a is a beam scanning angle command signal, b is a phase shifter drive signal, C is a target detection multiplier, dFi,
Angle error signal, e is beam shape switching signal, Σ is monopulse sum channel, Δ is monopulse difference channel, TP
The scanning time by the hape/sil beam, h is the scanning time by the fan beam, θmu2 is the scanning angle range in the horizontal direction, θI
IL is the scanning angle range in the horizontal direction, θliF is the beam width of the pencil beam, θBF is the beam width of the Hafian beam, ω
is the beam scanning speed H, N is the ratio of the beam widths of the fan beam and the pencil beam, and TM is the time required to obtain the angular error signal in the monopulse difference channel. Note that the same or corresponding parts in the figures are denoted by the same reference numerals. Agent Shin Kuzuno −

Claims (1)

[Scope of Claim] A radar device that performs beam scanning electronically includes a phase shift calculation control circuit that calculates the phase shift amount of a phase shifter of a large number of antenna elements constituting a phased array antenna; a phase data storage circuit for storing phase data for forming a fan beam; an adder for adding the output of the phase shift calculation control circuit and the output of the phase data recording circuit; a beam position controller that is connected to the phase data storage circuit and includes a switch that supplies the output of the phase data storage circuit to the -F adder, and controls all of the phase shifters of the plurality of antenna elements; When in high-speed automatic target acquisition mode, fan beam noheam simultaneously processes monopulse difference channels and monopulse sum channels in a wide range of directions. A signal processor that detects all target signals in one channel and obtains an angular error signal indicating the direction of the target in the difference channel, and generates a beam shape switching signal to the switch after receiving the first detection signal from the signal processor. Then, the input of the adder is set to zero, the fan beam is switched to the pencil beam, and the beam directing angle to direct the pencil beam to the target direction is calculated based on the angle error signal from the signal processor, and the beam scanning is performed. An information processor for generating an angle command signal to the phase shift calculation control circuit is provided, and the information processor generates phase data for beam scanning from the phase shift calculation control circuit and fan beam forming phase data from the phase data storage circuit. The fan beam is scanned at high speed, and when the target is detected, the fan beam is fixed there and the fan beam is scanned at high speed in a wide range of angles. A radar characterized in that the angle is calculated based on the angle error signal of the monopulse difference channel, and the adder is separated from the phase data storage circuit to form a pencil beam and direct it in that direction to quickly track the target. Device.