RU2295739C1 - Arrangement of identification of shooting systems - Google Patents

Abstract

FIELD: the invention refers to radiolocation technique.

SUBSTANCE: it may be used in reconnaissance radar stations for identification of the class of shooting systems according to the results of measuring current coordinates of a shell (a mine, a rocket) on a trajectory. The arrangement of identification of shooting systems has a storage device, a block of smoothing of the received rectangular coordinates of the trajectory of the flight of a shell, a block of transformation of the smoothed coordinates, two threshold arrangements, a memory block of conditional densities of probability of the target belonging to one of the four classes, a comparison arrangement and a block analyzing increases of values of a Doppler frequency. At that it has a block of calculation of additional parameters of the trajectory, two blocks for the analysis of the parameters of the trajectory, a block of nullification of conventional indexes of probability of belonging of the target to the corresponding class, four blocks of getting conditional indexes of probability of the belonging of the target to the corresponding class, a block for summing up the conventional indexes of belonging of the target to the corresponding class, a block of comparison of sums of the conventional indexes of probability of belonging of the target to the corresponding class.

EFFECT: increases probability of correct identification of shooting systems.

2 dwg

Description

The invention relates to the field of radar technical means of recognizing the class of firing artillery systems of the enemy by measuring the current coordinates of the projectile (mines, missiles) on the trajectory.

A recognition device for firing systems is known [1], in which its current coordinates on the ascending branch of the trajectory, measured as a result of auto-tracking of a projectile (missiles, mines), are smoothed, resulting in coordinate estimates, horizontal components of speed and acceleration at any point in the tracking interval. After that, the horizontal components of velocity and acceleration are calculated for the middle of the observation interval. Further, according to the obtained estimates of the horizontal components of velocity and acceleration for the middle of the observation interval, the value of the ballistic function is determined.

Determining the nature of the trajectory section - active or passive - is carried out by the sign of the ballistic function. For an active site, according to a preselected threshold of ballistic function, the target is assigned to classes 5 or 6: class 5 - tactical missiles (active site), class 6 - active-rockets, active-reactive mines (ARS, AWP). For a passive section of the trajectory, the values of horizontal velocities and accelerations are used to determine the conditional probability densities of the observed ballistic target in each of four classes:

Grade 1 - howitzers;

Grade 2 - mortars;

Grade 3 - MLRS;

Grade 4 - tactical missiles (passive section).

The assignment of an object to one or another class is carried out according to the maximum of the conditional probability density of belonging of the observed ballistic target to one of the four classes.

If preliminary recognition by the value of the ballistic function and by the maximum of the conditional probability density of the target's belonging to one of the four classes showed that the target belongs to the 2nd, 4th, 5th or 6th grade, additional recognition is not performed. If preliminary recognition showed that the target belongs to the first (artillery) or third (MLRS) classes, an additional refinement of the target's belonging to the first or third classes is made according to the value of the Doppler frequency of the signal. With an increase in the Doppler frequency (an increase in velocity), the target belongs to the third class. If the Doppler frequency decreases - the target is on the passive section of the trajectory - an additional analysis of the projectile speed at the midpoint of the observation section is performed. If the velocity of the projectile in the middle of the observation area is less than the threshold value, the target belongs to class 1, otherwise the target class is taken equal to that obtained after preliminary recognition.

This device, shown in figure 1, includes the following blocks:

1 - block smoothing the obtained rectangular coordinates of the projectile flight path;

2 - block conversion of smooth coordinates;

3 - the first threshold device;

4 - memory block of conditional probability densities of the target belonging to each of the four classes;

5 - a unit for determining the maximum of the conditional probability density of a target belonging to one of four classes;

6 - second threshold device;

7 - storage device;

8 is a comparison device;

9 is a block analysis of increasing values of the Doppler frequency;

10 - the third threshold device.

The device adopted for the prototype works as follows.

In the process of auto tracking, the values of the current rectangular coordinates of the projectile flight path and the Doppler frequency of the signal are fed to the input of block 7, where the values of the Doppler frequency of the signal are stored and transmitted from the first output to the second input of the analysis unit of increasing values of the Doppler frequency 9, and the rectangular coordinates of the projectile flight path from the second the outputs of block 7 are transmitted to the input of block 1. Next, in block 1, the rectangular coordinates of the projectile’s flight path are smoothed out, resulting in smoothed evaluation of rectangular coordinates, velocity and acceleration of the projectile at the end of the observation interval. In the unit for converting the smoothed coordinates 2, the rectangular coordinates of the projectile’s flight path, velocities and accelerations of the projectile are recounted in the middle of the observation interval, the horizontal components of the velocities and accelerations in the middle of the observation interval are calculated, and the ballistic function E is calculated. After that, the sign is analyzed in the first threshold device 3 ballistic function E.

If E≥0 - control is transferred to block 4, where the constants are stored, the values of which are equal to the conditional probability densities of the obtained values of the horizontal components of speed and acceleration to each of the four classes (1, 2, 3, or 4). In block 5, the membership of the target in the corresponding class is determined by the maximum conditional probability density of the probability that the target belongs to one of the four classes, after which control is transferred to the comparison device 8.

If E <0 - control is transferred to the second threshold device 6, where, in accordance with a pre-selected threshold of the ballistic function, the target is assigned to class 5 or 6, after which control is transferred to the comparison device 8.

The comparison device 8 analyzes the belonging of the target to 1 or 3 classes. If the target belongs to the 2nd, 4th, 5th or 6th classes, recognition of the target's class is considered completed. If the target belongs to class 1 or 3, control is transferred to the first input of block 9, where the presence of an increase in the Doppler frequency values received at the second input of block 9 from the first output of the storage device 7 is analyzed. If the Doppler frequency increases, the target belongs to class 3 and recognition of the target class is considered complete, otherwise control is transferred to the third threshold device 10, where the projectile velocity at the midpoint of the observation site Vcp is compared with the threshold value V _threshold .

If Vcp <V _threshold - the target belongs to class 1 and recognition of the target class is considered fulfilled, otherwise (Vcp> V _threshold ) - target recognition is considered fulfilled, the target class does not change and remains equal to that obtained at the preliminary recognition stage.

However, the significance of the recognition class of the firing system is significantly affected by the mean square errors of determining the horizontal components of velocity and acceleration. First of all, this concerns the horizontal component of acceleration, the root mean square error of the determination of which can be up to 40% of its true value. An unambiguous assignment of a target to class 3 by the value of the Doppler frequency is possible only if it increases (i.e., when observing the active part of the trajectory). In addition, modern artillery shells have flight speeds comparable with the speeds of rockets at the end of the active section, which, together with errors in determining horizontal speeds and accelerations, leads to errors in determining the class of firing systems (mixing up classes).

The disadvantages of the prototype are the above facts, leading to a decrease in the probability of recognition of firing systems belonging to 1 or 3 classes.

The aim of the present invention and the technical result is to increase the reliability of recognition of goals related to 1 or 3 classes.

This goal is achieved by the fact that instead of analyzing the magnitude of the speed Vcp, additionally introduced new recognition features (parameters) are analyzed:

- values of the trajectory parameters at the midpoint of the observation site:

Wcp is the acceleration value at the midpoint;

E is the value of the ballistic function at the midpoint;

- the value of one of the parameters of the firing systems:

C is the value of the ballistic coefficient;

- the values of the relations of the trajectory parameters at the midpoint of the observation site:

E / Vcp - value of the ratio of the ballistic function to the velocity at the midpoint;

Wcp / Vcp - the value of the ratio of acceleration to speed at the midpoint.

Using the calculated parameters of the trajectory at the midpoint of the observation site, their ratios E / Vcp and Wcp / Vcp are calculated, as well as the value of the ballistic coefficient C:

Where

E is the value of the ballistic function at the midpoint;

N (y) is the value of the function of air density depending on the height of the trajectory at the midpoint - Nsr:

G (Vcp) - air resistance function:

G (Vcp) = 4.74 Vcp Cx 10 ^-4 ,

Cx is the drag function calculated by the averaged dependencies:

As the calculations performed on the model and according to the authors' records of real trajectory measurements of the projectile flight showed that it is necessary to first analyze the values of E and Wcp:

When inequalities (1) or (2) are fulfilled, the goal unambiguously belongs to class 3 and the recognition process stops at that. If at least one of the inequalities (1) or (2) is not satisfied, it is necessary to continue the identification of goals. For this, we introduce the concept of conditional indicators of the probability that the target belongs to the corresponding i-th class (i = 1,3) P _{i, j} by j parameters, j = 0,1,2,3. As the parameters by which P _{i, j} is calculated _, E, Wcp / Vcp, E / Vcp, and C are used, respectively. Immediately before determining conditional indicators of the probability that the target belongs to the corresponding class, their values are reset:

The values of P _{i, j are} determined by the following expressions:

The resulting conditional probabilities are summarized.

Assignment to the 1st or 3rd class is carried out according to the maximum value of the probabilities Ps:

Figure 2 shows a diagram of the proposed device, which allows the recognition of the class of explored targets.

The device includes the following blocks:

1 - block smoothing the obtained rectangular coordinates of the projectile flight path;

2 - block conversion of smooth coordinates;

3 - the first threshold device;

4 - memory block of conditional probability densities of the target belonging to each of the four classes;

5 - a unit for determining the maximum of the conditional probability density of a target belonging to one of four classes;

6 - second threshold device;

7 - storage device (memory);

8 is a comparison device;

9 is a block analysis of increasing values of the Doppler frequency;

10 - unit for calculating additional recognition parameters;

11 - the first block of the analysis of the parameters of the trajectory;

12 - second block analysis of the parameters of the trajectory;

13 - block zeroing conditional probability indicators;

14 - the first block of obtaining conditional probability indicators;

15 - the second block of obtaining conditional probability indicators;

16 - the third block of obtaining conditional probability indicators;

17 - the fourth block of obtaining conditional probability indicators;

18 is a block summing conditional probability indicators;

19 is a block comparing the sums of conditional probability indicators.

The inventive device operates as follows.

In the process of auto tracking, the values of the current rectangular coordinates of the projectile flight path and the Doppler frequency of the signal are fed to the input of block 7, where the values of the Doppler frequency of the signal are stored and transmitted from the first output to the second input of the analysis unit of increasing values of the Doppler frequency 9, and the rectangular coordinates of the projectile flight path from the second the outputs of block 7 are transmitted to the input of block 1. Next, in block 1, the rectangular coordinates of the projectile’s flight path are smoothed out, resulting in smoothed evaluation of rectangular coordinates, velocity and acceleration of the projectile at the end of the observation interval. In the unit for converting the smoothed coordinates 2, the rectangular coordinates of the projectile’s flight path, velocities and accelerations of the projectile in the middle of the observation interval are recalculated, the horizontal components of the velocities and accelerations in the middle of the observation interval are calculated, and the ballistic function E is calculated. After that, the sign is analyzed in the first threshold device 3 ballistic function E.

If E≥0 - control is transferred to block 4, where the constants are stored, the values of which are equal to the conditional probability densities of the obtained values of the horizontal components of speed and acceleration to each of the four classes (1, 2, 3, or 4). In block 5, the membership of the target in the corresponding class is determined by the maximum conditional probability density of the probability that the target belongs to one of the four classes, after which control is transferred to the comparison device 8.

If E <0 - control is transferred to the second threshold device 6, where, in accordance with a pre-selected threshold of the ballistic function, the target is assigned to class 5 or 6, after which control is transferred to the comparison device 8.

The comparison device 8 analyzes the belonging of the target to 1 or 3 classes. If the target belongs to the 2nd, 4th, 5th or 6th classes, recognition of the target's class is considered completed. If the target belongs to class 1 or 3, control is transferred to the first input of block 9, where the presence of increasing Doppler frequency values received at the second input of block 9 from the first output of memory device 7 is analyzed. If the Doppler frequency increases, the target belongs to class 3 and recognition of the target class is considered complete; otherwise, control is transferred to block 10 for calculating additional recognition parameters (Wcp / Vcp, E / Vcp and С), and then to the first block for analyzing the parameters of the path 11, where Xia analysis of inequalities (1).

If both inequalities (1) are satisfied, the goal belongs to class 3 and recognition of the target class is considered fulfilled.

If at least one of the inequalities (1) is not satisfied, the control from the output 1 of the first block of the analysis of the parameters of the path 11 is transferred to the second block of the analysis of the parameters of the path 12, where the analysis is carried out by inequalities (2).

If all inequalities (2) are fulfilled, the goal belongs to class 3 and recognition of the target class is considered fulfilled.

If at least one of the inequalities (2) is not satisfied, the control from the output 1 of the second block of analysis of the parameters of the trajectory 12 is transmitted sequentially:

- to block 13, where the conditional indicators of the probability that the target belongs to classes 1 and 3 are zeroed according to (3);

- on the first block of obtaining conditional indicators of the probability that the target belongs to the corresponding class 14, where the values of P _1,0 , P _{3,0 are} determined according to (4) as a result of analysis of the value of E;

- to the second block of obtaining conditional indicators of the probability that the target belongs to the corresponding class 15, where the values of P _1,1 , P _{3,1 are} determined according to (5) as a result of the analysis of the value of Wcp / Vcp;

- to the third block of obtaining conditional indicators of the probability that the target belongs to the corresponding class 16, where the values of P _1,2 , P _{3,2 are} determined according to (6) as a result of the analysis of the value of E / Vcp;

- to the fourth block of obtaining conditional indicators of the probability that the target belongs to the corresponding class 17, where the values of P _1,3 , P _{3,3 are} determined according to (7) as a result of the analysis of the value of C;

- to the unit for summing conditional indicators of the probability that the target belongs to the corresponding class 18, where the values Ps ₁ , Ps ₂ are calculated for classes 1 and 3, respectively, according to (8);

- to the unit for comparing the sums of conditional probability indicators 19, where the target is assigned to the corresponding class according to (9).

The use of the inventive device, as shown by the calculations carried out on the model, and according to the authors' records of real trajectory measurements of projectile flight, increases the recognition efficiency of the class of enemy firing systems in comparison with a similar device (prototype) by 20%.

Information sources

1. RF patent No. 2231084, G 01 S 13/06, 13/56, published June 20, 2004, bull. Number 17.

Claims (1)

A recognition system for shooting systems containing a sequentially connected storage device, a block for smoothing the obtained rectangular coordinates of the projectile flight path, a block for converting smoothed coordinates, a first threshold device, a memory block of conditional probability densities of the target belonging to each of the four classes, a unit for determining the maximum of the conditional probability density of the target belonging to one of four classes, a comparison device and an analysis unit for increasing Doppler hour values the cells, as well as the second threshold device, the input of which is connected to the second output of the first threshold device, and the first and second outputs of the second threshold device and the output of the unit for determining the maximum conditional probability density of the target belonging to one of four classes are combined with each other and with the input of the comparison device, wherein the first output of the storage device is connected to the second input of the analysis unit of the increasing values of the Doppler frequency, characterized in that series-connected b lock for calculating additional recognition parameters: the values of the ratio of the trajectory parameters at the midpoint of the observation site - the ballistic function to speed, acceleration to speed and the value of one of the parameters of the shooting systems - the ballistic coefficient, the first block of the analysis of the trajectory parameters by the values of the acceleration to the ballistic function at the midpoint observation site, the second block of analysis of the trajectory parameters at the midpoint of the observation site: values of acceleration, ballistic function, relations - a ballistic function to speed and acceleration to speed, a block of zeroing conditional indicators of the probability that the target belongs to the corresponding class, a first block of obtaining conditional indicators of the probability that the target belongs to the corresponding class, a second block of obtaining conditional indicators of the probability that the target belongs to the corresponding class, a third block of obtaining conditional probability indicators of belonging of the target to the corresponding class, the fourth block for obtaining conditional probability indicators for the target’s belonging to the corresponding class, the summation block of conditional probabilities of the target’s belonging to the corresponding class, the unit for comparing the sums of the conditional probability indicators of the target’s belonging to the corresponding class, the first output of the analysis unit for increasing the values of the Doppler frequency connected to the input of the block for calculating additional recognition parameters, and the second the output of the comparison device is combined with the second outputs of the analysis unit of the increasing values of the Doppler frequency, the first and second of the blocks of analysis of the parameters of the trajectory, as well as with the first and second outputs of the unit for comparing the sums of conditional probability indicators, is the output of the device.

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