RU2548682C1 - Method of detecting and tracking target trajectory - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: method is carried out by passing an antenna beam through a region outside a sector with maximum allowable acceleration and rotational speed of the antenna, defined by capabilities of the drive of the antenna and mechanical strength thereof.

EFFECT: detecting and tracking trajectories of high-speed and highly manoeuvrable targets with a sufficiently short period of updating information in a given sector on the azimuth using all-round looking radar stations with an antenna in the form of a phased antenna array with electronic beam control on the elevation angle and mechanical rotation on the azimuth, having a considerable weight.

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Description

The invention relates to the field of radar and can be used to detect the trajectories of high-speed and intensively maneuvering targets using mobile radar stations (radars) of circular view with an antenna made in the form of a phased antenna array (PAR), providing an overview of the area with a beam sequentially moving along the elevation by electronic control, and in azimuth by mechanical rotation of the antenna.

There is a method of detecting and tracking the trajectory of a target, including detecting a target during a circular view of the radar zone, detecting and tracking the trajectory of a target in the strobe for detecting and confirming the trajectory (Farina A., Student F. Digital processing of radar information. Tracking of targets. - M .: Radio and Communication, 1993, p. 26-28).

The disadvantage of this method is a significant increase in the size of the strobe detection and tracking of the trajectories of high-speed and intensively maneuvering objects, which is a consequence of the characteristic for survey radars a long period of updating information (10-15 s). The increase in the size of the gates leads to an increase in the cost of time and energy resources required for inspection of the gates, as well as to an increase in the number of false trajectories. As a result, the radar information processing system is overloaded, the radar throughput is reduced.

The closest method is (Fig. 1) a method for detecting and tracking a target’s trajectory in a given sector in azimuth of size φ using a circular viewing radar with an antenna made in the form of a phased array antenna that performs an overview of the zone with a beam sequentially moving along the elevation angle using electronic control, and in azimuth - with the help of mechanical rotation of the antenna, and after each inspection of the said sector, the direction of rotation of the antenna is changed, after the next inspection of the said sector, in which om the decision on the detection or absence of detection of the target trajectory is made, the inspection of the mentioned sector is stopped and the all-round radar zone review is continued (RF patent No. 2347236).

The closest method has the following disadvantages.

To obtain a sufficiently short period of updating information in a given sector in azimuth, the closest method requires a quick change in the position of the antenna in this sector with a change in the direction of rotation. In mobile surveillance radars, the antennas of which have a significant mass (more than tons), such antenna movements will inevitably be accompanied by significant dynamic loads on the antenna drive and the antenna itself and can cause deformation of the antenna structure and, as a result, changes in its characteristics. Thus, in radars with antennas having a significant mass, the application of the closest method for detecting and tracking the trajectories of high-speed and intensively maneuvering targets can be very problematic.

The problem being solved (technical result), therefore, is the detection and tracking of the trajectories of high-speed and intensively maneuvering targets with a sufficiently short period of updating information in a given sector in azimuth using a radar circular viewing with an antenna made in the form of a headlamp with electronic beam control in elevation and mechanical rotation in azimuth, having a significant mass.

This result is achieved by the fact that in the method of detecting and tracking the target trajectory in a given sector in azimuth of size φ using a radar station with a circular view with an antenna made in the form of a phased array antenna that performs a field survey of the beam sequentially moved along the elevation angle using electronic control and in azimuth — by mechanical rotation of the antenna, according to the invention, when the beam is in the said sector, the antenna is rotated with a given speed ω, determined on the basis of of the time required for inspection of the sector after the beam from said sector antenna is rotated with acceleration α, on the basis of predeterminable features antenna actuator and its mechanical strength, wherein

if when the beam moves in azimuth to the middle of the region outside the given sector in azimuth, the antenna rotation speed does not reach the maximum permissible antenna rotation speed ω _max , which is also set based on the capabilities of the antenna drive and its mechanical strength, then when the beam is in azimuth further than the middle of the mentioned region the rotation of the antenna is slowed down with a deceleration of -α until the rotation speed ω is reached,

, затем вращение антенны замедляют с замедлением -α до достижения скорости вращения ω.if when the beam moves in azimuth to the middle of the region outside the specified sector in azimuth at any position of the beam in azimuth φ _i, the antenna rotation speed reaches ω _max , then the antenna continues to rotate at this speed ω _max within the azimuth angle determined from expressions: $${\varphi }_{\omega m\mathrm{but}\mathrm{to}\mathrm{from}}={\varphi }_i+360-\varphi +\frac{\left({\omega }_{m\mathrm{but}\mathrm{to}\mathrm{from}}^2-{\omega }^2\right)}{\alpha }$$

, then the rotation of the antenna is slowed down with a deceleration of -α until the rotation speed ω is reached.

The essence of the proposed method is as follows.

The reduction of dynamic loads on the antenna drive and the antenna in the claimed method is ensured by the fact that a given sector in azimuth of size φ and an area outside this sector are inspected with a constant direction of rotation of the antenna and without stopping its rotation.

The antenna rotation speed ω within a given sector in azimuth is constant, it is determined on the basis of the time taken to inspect this sector when detecting and tracking target trajectories.

A sufficiently short period of updating information in a given sector in azimuth is provided due to the fastest possible passage of the ray in azimuth outside the sector. In this case, the antenna rotation acceleration α and the maximum allowable antenna rotation speed ω _max in this area are set based on the capabilities of the antenna drive and its mechanical strength.

After the beam exits from a given sector in azimuth, the antenna rotates with acceleration α, then the region outside the specified sector in azimuth can be passed by the antenna beam in one of two ways.

The first option (figure 2) is implemented when, when the beam moves to the middle of the region outside the given sector in azimuth, the antenna rotation speed does not reach the maximum permissible antenna rotation speed ω _max . In this case, when the position of the beam in azimuth is further than the middle of the region, the rotation of the antenna is slowed down with a deceleration of -α until the rotation speed ω is reached. After slowing down the rotation of the antenna, the beam appears at the beginning of a given sector in azimuth.

The period of updating information in a given sector in azimuth in this case is determined by the formula:

The second option (Fig. 3) is realized when, when the beam moves to the middle of the region outside the given sector in azimuth at any position of the beam in azimuth φ _i, the antenna rotation speed reaches ω _max . In this case, with the following positions of the beam within the angle in azimuth, determined from the expression:

the antenna continues to rotate at this speed ω _max , then the rotation of the antenna is slowed down with a deceleration of -α until the speed of rotation ω reaches the beginning of the mentioned sector. After slowing down the rotation of the antenna, the beam appears at the beginning of a given sector in azimuth.

The period of updating information in a given sector in azimuth in this case is determined by the formula:

From the point of view of the shortest period of updating information in a given sector in azimuth, the first option is preferable, since in this case the transit time of the region outside the sector is shorter. The choice of option is carried out depending on the values of φ, α, ω, ω _max .

Thus, the detection and tracking of the trajectories of high-speed and intensively maneuvering targets with a sufficiently short period of updating information in a given sector in azimuth is provided using a radar circular view with an antenna made in the form of a headlamp with electronic control of the beam in elevation and mechanical rotation in azimuth, having a significant mass, that is, the claimed technical result is achieved.

The invention is illustrated by the following drawings.

Figure 1 - directions of rotation of the antenna in the closest way.

Figure 2 - location of the areas of uniform, accelerated and slowed rotation of the antenna in the first embodiment of the passage of the beam of the radar field of view.

Figure 3 - the location of the areas of uniform, accelerated and slowed rotation of the antenna in the second embodiment of the passage of the beam of the radar field of view.

Figure 4 - block diagram of a radar that implements the inventive method (double arrow indicates mechanical connection).

5 is a block diagram of the drive antenna 8.

The radar that implements the inventive method (figure 4), contains an antenna 1, a beam control device 2, the output of which is connected to the control input of the antenna 1, serially connected transmitter 3, antenna switch 4, receiver 5 and calculator 6 that performs the detection of target trajectories and control the speed of rotation of the antenna 1, the first output of which is the radar output, as well as the synchronizer 7 and the antenna drive 8, mechanically connected to the antenna 1, while the signal input / output of the antenna 1 is connected to the input / output of the antenna switch 4, and its coordinate output - with the second input of the calculator 6, the second output of the calculator 6, which is the output of a signal proportional to the speed of rotation of the antenna 1, is connected to the input of the drive of the antenna 8, the coordinates of the boundaries of the given sector in azimuth are fed to the third input of the calculator 6, four outputs of the synchronizer 7 are connected respectively to the input of the beam control device 2, the input of the transmitter 3, the second input of the receiver 5 and the fourth input of the calculator 6.

The drive of the antenna 8 (Fig. 5) consists of a power transmission 9, an engine 10 and a rotational speed control unit of the antenna 11, while the shaft of the engine 10 is mechanically connected to the input of the power transmission 9, which, in turn, is mechanically connected to the antenna 1, and the electrical input of the engine 10 is connected to the output of the rotation speed control unit of the antenna 11, the input of which is the input of the signal from the second output of the calculator 6 and controlling the rotation speed of the antenna 1.

A radar that implements the inventive method can be performed using the following functional elements.

Antenna 1 - PAR with one-dimensional electronic beam control in elevation and mechanical rotation in azimuth (Radar Reference. Edited by M. Skolnik, vol. 2. - M .: Sov. Radio, 1977, p.138).

Beam control device 2 is a digital computer that implements the well-known algorithm for calculating the distribution of the state of phase shifters in the headlamp fabric and forming a beam in a given direction by elevation (Radar Reference. Edited by M. Skolnik, vol. 2. - M .: Sov. Radio 1977, p. 141-143).

Antenna switch 4 - balanced antenna switch based on a circulator (A.M. Pedak et al. Guide to the basics of radar technology. Edited by VV Druzhinin. - M.: Military publishing house MO, 1967, s.166-168).

Transmitter 3 - a multi-stage pulse transmitter on a klystron, made on the basis of a well-known transmitter (AM Pedak et al. Guide to the basics of radar technology. Edited by VV Druzhinin. - M.: Military publishing house MO, 1967, p. 278-279, fig. 7.2).

Receiver 5 - superheterodyne receiver, made on the basis of the well-known receiver (AM Pedak and others. Guide to the basics of radar technology. Edited by VV Druzhinin. - M .: Military publishing house MO, 1967, S. 343-344, Fig. 8.1 )

Calculator 6 is a digital calculator. Calculator 6 implements the well-known target trajectory detection algorithm (SZ Kuzmin, Fundamentals of the theory of digital processing of radar information. - M .: Sov. Radio, 1974, p. 285-287), the moments of the beginning of acceleration and deceleration of antenna rotation outside a given sector are calculated in azimuth based on the given values of φ, α, ω, ω _max .

Synchronizer 7 - is made on the basis of a master oscillator and a chain of frequency dividers connected in series (Radar devices (theory and construction principles). Edited by VV Grigorin-Ryabov. - M .: Sov. Radio, 1970, p. 602 -603).

Antenna drive 8 - drive (Russian Encyclopedic Dictionary, book 2. - M .: Big Russian Encyclopedia, 2000, p.1248).

Power transmission 9 - gearbox (Tipugin V.N., Weitsel V.A. Radio control. - M.: Sov. Radio, 1962, p. 578).

Engine 10 - DC machine (Bruskin D.E., Zorokhovich A.E., Khvostov B.C. Electric machines, part 2. - M .: Higher school, 1987, pp. 195-203).

The control unit for the speed of rotation of the antenna 11 is a control unit for the speed of rotation of the motor shaft. Methods of controlling the speed of rotation of the motor shaft are described in the source: Bruskin D.E., Zorokhovich A.E., Khvostov B.C. Electric cars, part 2. - M.: Higher School, 1987, p. 281-287.

Consider the work of the radar that implements the inventive method.

According to the signals of the beam control device 2, the beam of the antenna 1 is electronically moved along the elevation angle, and due to the rotation of the antenna 1, it moves in azimuth. At the same time, at the input of the transmitter 3, by the commands of the synchronizer 7, start pulses are received, which provide the radiation of the probing signal in the consecutively examined directions. The period of updating information is initially equal to the period of the circular review of the zone.

The signal reflected from the target through the antenna 1 and the antenna switch 4 enters the receiver 5, where it is converted to an intermediate frequency, filtered, amplified. At the second input of the calculator 6 from the coordinate output of the antenna 1 receives the coordinates of the antenna beam, and from the output of the receiver 5 - the filtered and amplified signal. In the calculator 6, the received signal is compared with the detection threshold, above which a decision is made to detect the target. From the synchronizer 7 to the fourth input of the calculator 6, a signal is proportional to the moment of radiation of the probing signal. By the magnitude of the delay of the probe signal in the calculator 6 according to well-known formulas (Theoretical Foundations of Radar. Edited by Ya.D. Shirman. - M .: Sov. Radio, 1970, p.221), the distance to the target is determined.

If the coordinates of the boundaries of a given sector in azimuth, in which high-speed and intensively maneuvering targets are expected, are received from the external source of target designation at the third input of calculator 6, then this sector should be examined with a shorter period of updating information.

For this, the value of the current azimuthal coordinate of the beam of the antenna 1 supplied to the second input of the calculator 6 is compared with the position of the boundaries of the given sector in azimuth. At the time point preceding the beginning of this sector, a signal is issued from the second output of the calculator to the input of the antenna drive 8, according to which the antenna rotation speed is set equal to the given rotation speed ω. A given sector in azimuth is examined with a constant antenna rotation speed ω.

When the beam exits from a given sector in azimuth according to the signal from the second output of the calculator 6 to the input of the antenna drive 8, the antenna rotates with acceleration α. Then, if when the beam moves to the middle of the region outside the given sector in azimuth, the antenna rotation speed does not reach ω _max , then when the beam is in azimuth further than the middle of the mentioned region, the antenna rotation is slowed down with a -α slowdown until the rotation speed ω is reached. If when the beam moves to the middle of the region outside the given sector in azimuth at any position of the beam in azimuth φ _i, the antenna rotation speed reaches ω _max , then the antenna continues to rotate at a speed ω _max within the azimuth angle determined from expression (2 ), then the rotation of the antenna is slowed down with a deceleration of -α until the rotation speed ω is reached.

At the end of the deceleration of the antenna rotation speed, the beam appears at the beginning of a given sector in azimuth.

When examining a given sector in azimuth, a probe signal is emitted at each beam position and reflected signals are received. If a reflected signal is detected, then the boundaries of the detection strobe, and then the confirmation and tracking gates of the target trajectory, which are examined during subsequent inspections of a given sector in azimuth, are calculated in calculator 6. When fulfilling the criterion for detecting the target path, the path parameters from the first output of the calculator 6 are issued to the consumer of radar information. If the coordinates of the boundaries of a given sector in azimuth continue to arrive at the third input of the calculator 6, then the inspection of this sector continues, and the detection and tracking of the trajectories of targets in this sector with the issuance of their parameters to the consumer continues. If the receipt of the coordinates of the boundaries of the given sector in azimuth has ceased, then the inspection of this sector is terminated and the usual circular overview of the entire zone continues with the detection and tracking of the target paths with the corresponding period of updating information.

Thus, the inventive method provides detection and tracking of trajectories of high-speed and intensively maneuvering targets with a sufficiently short period of updating information in a given sector in azimuth using a radar circular view with an antenna made in the form of a headlamp with electronic beam control in elevation and mechanical rotation in azimuth having a significant mass, that is, the claimed technical result is achieved.

Claims (1)

A method for detecting and tracking a target’s trajectory in a given sector in azimuth of size φ using a round-robin radar station with an antenna made in the form of a phased array antenna that performs a field survey with a beam sequentially moved along the elevation angle using electronic control, and in azimuth, using mechanical rotation of the antenna, characterized in that when the position of the beam in the said sector, the antenna is rotated with a given speed ω, determined on the basis of the time required to inspect this sector and, after the beam from said sector antenna is rotated with acceleration α, on the basis of predeterminable features antenna actuator and its mechanical strength, wherein
if when the beam moves in azimuth to the middle of the region outside the given sector in azimuth, the antenna rotation speed does not reach the maximum permissible antenna rotation speed ω _max , which is also set based on the capabilities of the antenna drive and its mechanical strength, then when the beam is in azimuth further than the middle of the mentioned region the rotation of the antenna is slowed down with a deceleration of -α until the rotation speed ω is reached,
if when the beam moves in azimuth to the middle of the region outside the specified sector in azimuth at any position of the beam in azimuth φ, the antenna rotation speed reaches ω _max , then the antenna continues to rotate at this speed ω _max within the azimuth angle determined from expressions:

, then the rotation of the antenna is slowed down with a deceleration of -α until the rotation speed ω is reached.

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