JP2668966B2 - Radar equipment - Google Patents

Description

The present invention relates to a radar device, and more particularly to a two-dimensional electronic scanning phased array radar capable of irradiating a beam in an arbitrary direction of a three-dimensional space at an arbitrary time.

(Background of the Invention) In a defense radar, it is required to scan the entire search space in a shorter time with the improvement of the high-speed flight ability and the high turning ability of an aircraft, a guided flying object, and the like. On the other hand, the adoption of microwave-absorbing materials and the adoption of shapes that avoid the reflection of microwaves, etc., have caused the reflection cross-section of aircraft requiring acquisition and guided flying objects to continue to decrease. Is being forced to irradiate with energy and many transmitted pulses.

(Problems to be Solved by the Invention) However, shortening the scan time and increasing the number of transmission pulses per specific direction (hereinafter referred to as hit number) are mutually exclusive requirements, and are used in air traffic control. Since the beam scanning angular velocity is constant in such a mechanical rotation type radar, it is impossible to meet the demand because an attempt to shorten the scanning time leads to a decrease in the number of hits.

There is also a phased array radar that performs so-called two-dimensional electronic scanning in the azimuth and elevation directions. In this case, as long as the planar array is mechanically rotated, it is possible to control the beam scanning angular velocity to some extent. Due to the restriction due to the above, there is a problem that it is not possible to sufficiently deal with an aircraft / guided flying vehicle coming from an unspecified direction.

An object of the present invention is to use a polyhedral phased array or a cylindrical phased array capable of emitting a beam in an arbitrary direction at an arbitrary time in a three-dimensional space, and to use various types of terrain conditions, weather conditions, radio wave environment conditions and radar operation purposes. By providing the radar operator with means for freely specifying the number of hits, the beam scanning period, etc. for each region according to the conditions,
An object of the present invention is to provide a radar capable of scanning a beam that matches an operational purpose.

(Means for Solving the Problem) The radar device of the present invention has the following means configuration in order to achieve the above object.

That is, the radar device of the present invention is a two-dimensional electronic scanning phased array type radar device that irradiates a beam to a three-dimensional space, and electronically transmits and receives in a given direction in a three-dimensional space at a given time by a beam scanning control signal. An antenna capable of forming a beam; a pulse compression form expressing a plurality of pairs of a transmission pulse width and a pulse width after pulse compression applied to a reception pulse is built in, and the antenna is provided with a pulse compression form selection signal from the outside. A receiver capable of selecting a pair of pulse compression modes in real time; among a plurality of pre-programmed signal processing modes as target detection methods including pulse Doppler and MTI methods applied to the output of the receiver A processing signal capable of selecting one of the signal processing modes in real time in response to a signal processing mode selection signal from the outside; Area setting means for dividing the search space into a plurality of divided areas according to topographical conditions, meteorological conditions, and radar operation conditions; among the pulse compression mode and the signal processing mode applied to the divided areas for each of the divided areas A processing designation means for allocating an appropriate one; a beam scanning period for beam scanning in each divided region is designated by a relative number based on the period of any one of the divided regions. Beam scanning designation means; and a beam scanning / transmission sequence control program for controlling beam scanning and transmission sequences by receiving settings and designations from the area setting means, the processing designation means and the beam scanning designation means, respectively. A beam scanning control signal, a pulse compression mode selection signal, and a signal processing mode selection for the antenna, the receiver, and the signal processor, respectively. It is characterized in that it comprises a; and a system controller for sending a control signal.

(Examples) Examples of the radar device of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of a radar device of the present invention. In FIG. 1, 100 has a cylindrical shape, and a transmission power transistor is one of the antenna elements.
An omnidirectional electron beam scanning cylindrical active phased array antenna, which is integrated as a single structure, 200 is a receiving device, 300 is a signal processing device, 400 is a command and control device, and 500 is a system control computer. In the receiving device 200, 210 is a pulse expander, 220 is a pulse compressor, 230 is a detector, and 410 is a display, 42 in the command and control device 400.
0 is an operation panel.

The operation of the present invention will be described with reference to FIG. First, the operator from the operation panel 420
The area is set according to the radio wave environment condition and the radar operation condition, and the entire search direction area is divided into a plurality of small areas.

FIG. 2 shows an example of setting a region. Next, the operator specifies the pulse compression mode and the signal processing mode to be carried out in each small area from the operation panel 420 by selecting one from the menus built in at the design stage in advance.
In addition, for each area, the period for beam scanning of that area is specified by a ratio.

 Table 1 shows an example of such designation.

Table 1 shows an example set based on the following intentions.

(1) A long transmission pulse width (extended pulse width) is selected because a long distance requires a large amount of power.

(2) A short compression pulse width is selected because a highly accurate position measurement is required for a short distance target.

(3) In a short distance, high power graph caused by ground surface reflection Because of the presence of noise clutter, pulse Doppler processing of more hits is performed for shorter distances, thereby realizing a large signal-to-clutter power ratio improvement.

(4) The closer the threat target is, the higher the threat level is, the greater the azimuth position change per unit time is, and the more precise tracking performance is required, so that a short beam scanning period is assigned.

(5) A short compression pulse width, a multi-hit pulse Doppler process, and a short beam scanning cycle are assigned to the important search airspace (area D).

Upon receiving the operator designation information 450 from the operation panel 420, the system control computer 500 first calculates the beam scanning time required for beam scanning each area once, and then the beam scanning cycle designated for each area. The entire beam scanning program is edited according to (ratio), the beam scanning cycle for each area is calculated, and the beam scanning program information 504 is sent to the display 410. Table 2 shows an example of the beam scanning period for each region calculated in this way. The operator confirms the beam scanning program displayed on the display unit 410, If necessary, corrections are made from the operation panel 420 to fix the beam operation program.

The system control computer 500 sends the beam scanning control signal 501 to the cylindrical active phased array antenna 100 in real time according to the determined beam scanning program.
The pulse compression form selection signal 502 is sent to the pulse stretcher 210 and the pulse compressor 220, and the signal processing form selection signal 503 is sent to the signal processing device 300 to control the operation of the entire radar system.

The pulse expander 210 receives a pulse compression mode signal 502 from the system control computer 500, selects a pulse expansion device that generates a specified expansion pulse width from a plurality of pre-installed pulse expansion devices in real time, and generates a transmission IF signal 151 in real time. Output. Cylindrical active phased array antenna 100
Receives the transmission IF signal 151 and the beam scanning control signal 501, forms a transmission beam in a specified direction in real time, and irradiates microwave energy with a specified pulse width. At the same time, the signal received by the beam formed in the specified direction is demodulated and the reception IF
The signal 152 is output.

The pulse compressor 220 receives the pulse compression form signal 502 that is input in synchronization with the pulse stretcher 210, and selects one of a plurality of pre-installed pulse compression devices that generates a designation and a compressed pulse width in real time. Compressed IF signal 22
Output 5 The detector 230 receives the compressed IF signal 225 and performs a predetermined detection to generate a video signal 250.

The signal processing device 300 inputs the video signal 250 and the signal processing mode selection signal 503 at a timing synchronized with each other, selects a designated processing mode from a plurality of signal processing modes programmed in a preset stage in real time, and outputs the video. Signal 25
Process for 0.

In order to realize such processing, a signal processing processor whose signal processing function can be changed by firmware is adopted as a signal processing arithmetic element, and a plurality of signal processing modes (for example, 4-hit MTI processing, designed in advance in the firmware) are adopted.
(8-hit pulse Doppler processing and 16-hit pulse Doppler processing) are incorporated as a program, and can be selected in real time. The final processed output signal is displayed on the display 410.

(Effect of the Invention) As described above, according to the radar apparatus of the present invention,
It is not limited to the operation mode (beam scanning program) pre-installed at the design stage as in the past. Beam scanning, transmission pulse assignment and conventional radar adaptation to changes in radio wave environment conditions and aircraft flight conditions in the target search airspace There is an advantage that the beam scanning period corresponding to the mechanical rotation period can be programmed and implemented at the radar operator's will.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a radar apparatus according to the present invention, and FIG. 2 is a diagram showing an example of area setting in the apparatus according to the present invention. 100 …… Cylindrical active phased array antenna, 2
00: receiving device, 210: pulse expander, 220: pulse compressor, 230: detector, 300: signal processing device, 400:
… Command control device, 410 …… Display unit, 420 …… Operation panel, 500
...... System control computer.

Claims (1)

(57) [Claims] 1. In a two-dimensional electronic scanning phased array type radar device for irradiating a beam in a three-dimensional space, a beam scanning control signal can electronically form a transmission / reception beam in an arbitrary direction in the three-dimensional space. An antenna;
A pulse compression form expressing a plurality of pairs of a transmission pulse width and a pulse width after pulse compression applied to a reception pulse is built in, and a pair of pulse compression forms among them in response to an external pulse compression form selection signal. A receiver whose form can be selected in real time; and an external signal processing form from among a plurality of pre-programmed signal processing forms as a target detection method including a pulse Doppler and an MTI method applied to the output of the receiver. A signal processor capable of selecting one of the signal processing forms in real time according to the selection signal; and for dividing a radar search space into a plurality of divided areas according to terrain conditions, weather conditions, and radar operation conditions. Area setting means; and processing designating means for allocating an appropriate one of the pulse compression mode and the signal processing mode applied to each of the divided areas. Beam scan designating means for designating, for each of the divided areas, a beam scanning cycle for beam scanning within the area by a relative number based on a cycle of any one of the divided areas; A beam scanning / transmission sequence control program for controlling a beam scanning and transmission sequence by receiving settings and designations from the processing designation means and the beam scanning designation means, respectively, is created for the antenna, the receiver and the signal processor respectively. And a system controller for transmitting a beam scanning control signal, a pulse compression mode selection signal and a signal processing mode selection control signal.