RU2339970C1 - Method of scanning space using radar unit - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: method of scanning space using a radar unit is based on serial scanning of a region in space at different beam positions of the direction diagram of its antenna and combined processing of the scanning results. The radar unit is installed on a carrier. The beam of the direction diagram of its antenna is fixed in the azimuthal plane. Displacement of the beam on the azimuthal plane is done by moving the carrier in the horizontal plane with given flight time on a circular path or an almost circular path. When the carrier is moving in the horizontal plane, the beam of the direction diagram of the antenna is moved in the vertical plane within the limits of the elevation coverage.

EFFECT: provision for circular scanning of space using a "БРЛС" with the antenna fixed on a carrier and increased probability of detecting and intercepting a target.

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Description

The invention relates to the field of radar, in particular to radar stations mounted on moving objects.

A known method of reviewing airspace based on sequential viewing of space by continuous rotation with a constant angular velocity of the antenna beam around a vertical axis (Ed. By V.V. Grigorin-Ryabov, Radar devices, M .: Sov. Radio 1970, p. .86, 87, Fig. 4.3). This method is used in both ground and airborne radars (radar). The azimuth viewing sector is thus obtained equal to 360 °. In the practical implementation of this survey method in radars, an off-body parabolic antenna is usually used, which rotates in azimuth from a DC motor (G.B.Belotserkovsky, Fundamentals of Radio Engineering and Antennas. Part 2 Antennas M., Radio and Communications, 1983, p. 195) . Such a review is used, for example, in radar detection and target designation, which uses an antenna with a fan antenna pattern (BOTTOM), compressed in the horizontal plane (flat beam) and calculated to measure the azimuth of targets (G.B.Belotserkovsky, Fundamentals of Radio Engineering and Antennas Part 2, Antennas M., Radio and Communications, 1983, p. 189). However, in the case of installing a rotatable antenna outside the carrier fuselage, it becomes difficult to provide a wide radar coverage in azimuth and elevation due to distortion and shadowing of the bottom of the aircraft by the aircraft body and vertical stabilizers (M. Skolnik. Radar Handbook, Volume 3, M., Owls. Radio 1979, pp. 346-347). In the case of installing the antenna in the bow of the carrier, as is customary, for example, in fighter-interceptors of the Su-27 type (Fomin A.V. Su-27. History of the fighter. M., RA Intervestnik, 1999, pp. 212, 216, 217), obtaining a circular view is generally problematic due to the natural shadowing of the antenna pattern (BOTTOM) of the carrier body from the rear hemisphere.

The closest in technical essence is the way to view the airspace of a radar station, which is used in ground-based radars to control airspace, described in patent RU No. 2096802 C1 of 11/20/97. It is based on sequential viewing of a portion of space at different positions of a flat beam and joint processing of viewing results, while the position of the beam is changed by changing the angle of inclination of its plane and azimuth, or by changing the angle of inclination of its plane, azimuth and elevation, and joint processing is performed by storing angular beam positions at which objects tied to the same range are detected, and the calculation of the angular coordinates of common areas of space for these positions, which are taken as ordinates of the detected objects.

However, the survey of space used in this case by moving the beam in azimuth, elevation angle and changing the beam tilt cannot provide a circular view when installing the radar antenna in the nose of the carrier due to the natural shadowing of the bottom of the carrier body from the rear hemisphere. This does not allow to obtain a circular radar surveillance zone, which reduces the probability of target detection and interception.

The technical result of the proposed method is to achieve the possibility of a circular view of the radar space when installing the antenna in the nose of the carrier, as well as increasing the likelihood of detection and interception of targets.

The essence of the invention lies in the fact that the method of viewing space by a radar station is based on sequentially viewing a portion of space at different positions of the beam of its antenna pattern and processing the viewing results together. New in the proposed method is that the radar station is installed on the carrier, fix the beam pattern of its antenna in the azimuthal plane. The beam is moved in azimuth by moving the carrier in a horizontal plane with a predetermined flight time along a path that is either circular or close to circular. When the carrier moves in the horizontal plane, the beam of the antenna pattern is moved in the vertical plane within a given viewing sector in elevation. The flyby time of one circle can be determined from the expression:

T _o = K _{actual situation review} NT _{Pace mind} F 360 ° / θ _ds θ _mind

where K _review - the relative period of the review;

θ _az θ _mind - the width of the bottom in azimuth and elevation;

Ф _mind - the width of the sector of view by elevation;

_Pace T - the duration of the received signal burst;

N is the number of packets of the received signal

The beam of the antenna pattern is moved from the upper to the lower boundary of the field of view in elevation and, once it is reached, the beam of the antenna pattern is instantly returned back to the upper boundary of the field of view.

Figure 1 presents a radar station for implementing a method of viewing space by a radar station.

Figure 2 shows the path of the carrier and the position of the beam pattern of the antenna of the radar station.

Figure 3 shows the expanded viewing area in azimuth and elevation, where F _az is the width of the azimuth viewing area of 360 °, F _mind is the width of the viewing sector in elevation, θ _az is the width of the bottom in azimuth.

The radar station consists of an on-board digital computer (BTSC) 1, receiver 2, transmitter 3, antenna 4, antenna beam control unit 5 and indicator 6.

The all-round visibility mode is activated by the "All-round visibility" command from the cockpit periodically depending on the tactical situation. By this command, the carrier begins to move in a circle in the horizontal plane with a given time of its flight (T ₀ ). The command "Circular overview" is fed to the first input of the digital computer 1, from the first output of which it is transmitted to the input of the beam control unit of the antenna 5. In the beam control unit 5, a control signal is generated from its output to the first input of the antenna 4. The beam of the diagram the direction of the antenna of the radar station is recorded in azimuth (for example, in the direction of the construction axis of the carrier). Due to the movement of the carrier in a circle with an antenna beam fixed in azimuth, a circular overview of the space of the radar station in the azimuthal plane is carried out (figure 2).

The required viewing area in elevation (in the vertical plane) is provided by movement along the elevation angle of the beam of the radiation pattern. The motion of the beam of the radiation pattern of the antenna in elevation is as follows: commands from the first output of the computer 1 are received at the input of the beam control unit 5, in which signals are generated controls coming from its output to the first input of the antenna 4. The movement of the beam along the elevation angle begins at the moment the carrier moves in a circle at the command of the pilot. Moreover, in one direction, for example, from top to bottom, the beam moves at a speed calculated in the digital computer 1, based on the specified width of the viewing sector in elevation angle Ф _mind and the time of the carrier’s flight around the circle Т _о , set by the pilot to the first input of the digital computer 1. When the beam reaches the diagram directivity of the antenna of the lower boundary of the viewing sector along the elevation angle, the beam instantly moves to the upper boundary of the viewing zone. Instant (fast) beam movement in practice can be realized using a phased array antenna, which uses electronic beam control. The movement of the beam along the elevation angle is carried out during the entire flight of the carrier in a circle. Actually, due to the movement of the carrier in a horizontal plane in a circle and the movement of the beam along the elevation angle at a given speed, circular viewing is carried out by oblique vertical stripes (rows) with a step that corresponds to the beam width in azimuth θ _az (see figure 3). During the flight of the carrier in a circle of total n lines of view are formed, providing a circular view in the area of 360 · F _mind square. hail. Thus, a sequential circular overview of a portion of space is realized at different positions of the beam in azimuth and elevation.

In the process of all-round visibility, the antenna 4 of the radar station emits into the space the signal pulses arriving at its second input from the output of the transmitter 3, according to the commands received at its input from the second output of the digital computer 1. When the beam of the antenna radiation pattern at a given speed is irradiated, the target is irradiated the flow of time T _region Reflected signals from the target are received by antenna 4. During irradiation target N antenna receives the reflected signal bursts (T = NT _{Pace region)} which arrive with its output to the input of the receiver 2, whose transmission band (Δf) is compatible with the duration of the received burst _Pace T signals (Δf = 1 / T _pack ). The processed signals from the output of the receiver 2 are fed to the second input of the digital computer 1, where the coordinates of the detected targets are determined. From the third output of the digital computer 1, the coordinates of the detected targets in the form of target marks are displayed on indicator 6.

The proposed method allows to obtain a circular view of the radar station without the use of rotatable outside the fuselage antennas, significantly impairing the flight performance of the carrier (M. Skolnik. Radar Handbook, Volume 3, M., Sov. Radio 1979, p. 346, 347) . It can be used in promising developments of Su-Mig fighter-interceptors, whose radar antennas will be installed in the nose, as is customary in modern aircraft (Fomin A.V. Su-27. History of the fighter. M., RA Intervestnik, 1999 pp. .212, 216, 217).

The installation of the radar antenna in the nose of the carrier compared to the installation of the fuselage antennas provides the carrier with good flight performance and significantly reduces its effective dispersion area. All this allows the aircraft to have greater maneuverability and less noticeability for the enemy radar and, as a result, reduces the likelihood of being hit by enemy missiles. In addition, the flight of the aircraft in a circle will make it difficult to detect and track enemy radar. The proposed method without significant costs will provide an all-round radar view of Su-Mig fighters, as well as helicopters, which will significantly expand their tactical and technical characteristics. In particular, an interceptor fighter without the aid of ground guidance systems can intercept targets flying from any direction.

The proposed method can also be used to provide a circular view of the space with passive location stations installed on board the carrier.

Claims (3)

1. A way to view the space of a radar station, based on sequentially viewing a portion of space at different positions of the beam of its antenna pattern and processing the viewing results, characterized in that the radar station is mounted on a carrier, the beam of its antenna pattern is fixed in the azimuthal plane, and moving in azimuth of the beam is carried out by moving the carrier in a horizontal plane with a predetermined flight time along a trajectory either circular or near to a circular one, and when the carrier moves in the horizontal plane, the beam of the antenna pattern (BOTTOM) is moved in the vertical plane within a given viewing sector along the elevation angle. 2. The way to view the space of the radar station according to claim 1, characterized in that the time of flight by the carrier of one circle is determined from the expression T _o = K _{actual situation review} NT _{Pace mind} F 360 ° / θ _ds θ _mind where K _review - the relative period of the review; θ _az θ _mind - the width of the bottom in azimuth and elevation; Ф _mind - the width of the sector of view by elevation; _Pace T - the duration of the received signal burst; N is the number of packets of the received signal. 3. The way to view the space of the radar station according to claim 1, characterized in that the beam of the antenna pattern along the elevation angle is produced from the upper to the lower boundary of the field of view and, once it is achieved, the beam of the antenna pattern is instantly returned to the upper boundary of the field of view.

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