RU2735744C1 - Method for survey of single-position trilateration incoherent radar ranging of aerial targets - Google Patents

Abstract

FIELD: radio equipment.

SUBSTANCE: invention relates to radio engineering and can be used in ground-based systems of active survey single-position radar for detection and location, motion parameters and trajectories of air targets moving in space. To achieve technical result, movement of each air target is considered as a sequence of movements along polyhedral surface approximating to beam specified by vector of inclined range of target. To form trilateration system, auxiliary points B are used on abscissa and D on ordinate axes spaced by distance d from coordinate origin, and calculating range values R from them to the target, rectangular coordinates of the targets, forming the size of the target selection zones by range and angular coordinates. At repeated survey, values of inclined distances, azimuths and angles of targets are measured, and new samples are identified to initial sections of trajectories of previously detected targets. Values and coordinates are calculated for each tracked target. Using extrapolated values of rectangular coordinates from outputs of Kalman filters for formation of selection zones in points A_k+2 of trajectories of targets. Based on the results of subsequent surveys, trajectories of targets are detected by the criterion "three of three", values of distances traveled by targets during the time of scanning, modules of velocity vectors and spatial course angles, as well as flight altitudes and diving or pitch-up angles are calculated. In subsequent surveys coordinates of targets are measured and tracking and construction of their trajectories.

EFFECT: more accurate determination of parameters of movement and trajectories of the located aerial targets.

1 cl, 2 dwg

Description

The invention relates to the field of radio engineering and can be used in ground-based systems of active surveillance single-position radar for the detection and high-precision determination of the location, motion parameters and trajectories of air targets moving in space (CC).

At present, the main source of information about the movement of the CC are radar systems (radars), which allow solving the problems of detection, positioning and measuring the parameters of trajectories of the CC, as well as recognizing their types. This is due to the need to control the surrounding space in the conditions of complicating the methods of action of air targets, for example, aircraft. Since modern computer centers can move along complex trajectories with high (including hypersonic) speeds, when solving these problems, the reliability of the information obtained during the operation of the radar station must be ensured, necessary for making decisions, when operating in real time, determined by the speed of the radar.

Currently, the most widespread type of radar are active single-position systems that measure the ranges and angular coordinates (CC) of targets, that is, rangefinder-goniometric radar. The required range measurement accuracy and range resolution in these radars are ensured by using broadband sounding signals with intra-pulse angular modulation and pulse compression during reception. The highest accuracy of angular measurements in such radars is provided, as is known, by the monopulse method [1 - Leonov AI, Fomichev KI. Monopulse radar - M .: Radio and communication, 1984. - 312 p.]. In this case, the performance is achieved by using survey modes of operation, which make it possible to simultaneously determine the coordinates of the CC from the group, which are in the common area of the partial radiation patterns (DP), with their range resolution.

In typical surveillance radars, tracking strobes in range and angles differ significantly - the size of the strobe in range is much less than the size of the strobe according to the CC, which is noted in [2 - patent 2480782, RF. Method and device for resolving moving targets in angular directions in surveillance radar / Irkhin V.I., Zamyatina I.N. Appl. 6.10.2011, publ. 04/27/2013]. To ensure satisfactory characteristics of the radar, the resolution in angular coordinates (in linear measurement) should be close to the resolution in range. Here, a decrease in the size of the strobe formed around the primary target mark is achieved by increasing the measurement accuracy, which makes it possible to increase the reliability of determining the belonging of the VC mark to a particular trajectory and reduces the likelihood of visual confusion of the trajectories of closely located targets.

An analogue of the proposed method can be considered the method [3 - patent 2583849, RF, G01S 3/14, H01Q 25/02. Method of digital signal processing for survey monopulse amplitude summed-difference direction finding using an antenna array (options) and survey monopulse amplitude summed-difference direction finder using antenna array and digital signal processing / Dzhioev A.L., Omelchuk I.S., Fominchenko G L., Fominchenko G.G., Yakovlenko V.V. Appl. 04/13/2015, publ. 05/10/2016], which solves the problem of increasing the accuracy of measuring the AC when expanding the working area and increasing the measurement speed for a single-position survey direction finding. This method and a direction finder based on it make it possible, by choosing the angle of separation of the partial RP and the type of weighting function (WF), to form the direction finding characteristic (DF) of the device, which is almost linear in the working area, equal to the solution of a monopulse group of rays (MGL) at the half power level, and to provide monopulse measurement of AC with an accuracy not worse than 0.01 of the value of this zone.

However, the analogue [3] does not determine the location of targets and the parameters of their trajectories.

Expansion of the working area can also be achieved with the formation of cubic HRP [4 - Dzhioev A.L., Omelchuk I.S., Fominchenko G.L., Yakovlenko V.V. Signal processing method, operation algorithms and structure of an angular coordinate meter with a cubic direction finding characteristic in a survey digital monopulse radar system. Radio electronics journal [electronic journal]. 2017. No. 7. Access mode: http://jre.cplire.ru/jre/jul17/10/text.pdf]. It describes a signal processing method that provides a cubic direction finding characteristic and an analytical solution of the direction finding equation with an accuracy of 1% of the width of the partial radiation pattern in the working area, increased to the width of the monopulse beam group. An algorithm of operation of an angular coordinate meter with a cubic direction finding characteristic in a radar system based on an antenna array, which has an increased speed and accuracy, is presented.

However, the analogue [4] does not consider the simultaneous determination of two ACs and the parameters of the trajectories of moving targets.

Since high-precision simultaneous measurement of two CCs in a survey monopulse radar has some peculiarities, it is advisable to use the method [5 - patent 2615491, RF, G01S 13/44, H01G 21/00. Method of simultaneous measurement of two angular coordinates of a target in a survey amplitude monopulse radar system with an antenna array and digital signal processing / Dzhioev A.L., Omelchuk I.S., Yakovlenko V.V. Appl. 11/17/2015, publ. 5.04.2017]. Work [5] can also be considered an analogue of the proposed method; it shows that with simultaneous measurement of two target ACs, the value of one coordinate depends on the value of the other (orthogonal) coordinate relative to the equisignal direction (RSN). The presence of such a dependence introduces a methodical error into the measurement of the angular coordinate. To eliminate it, it is proposed to use a rectangular antenna array (AR) aperture and factorization of the weight function at the aperture; in this case, the measurement time is approximately three times shorter than in the case of using an elliptical aperture and / or a non-linear direction finding characteristic. This is explained by the fact that with a rectangular shape of the aperture and WF in the form of a product of two one-dimensional functions of coordinates on the aperture, the equations used cease to depend on the orthogonal coordinate [6 - Dzhioev A.L., Yakovlenko V.V. Elimination of the methodical error in measuring the angular coordinates of the target in the survey amplitude summed-difference digital direction finder based on the PAA // General Problems of Radioelectronics. Rostov-on-Don: FSUE "RNIIRS". 2015. Issue. 1. S. 47-57]. The AC measurement error is reduced to 1% of the AP width at the half-power level.

However, in the analogues [5, 6], methods of determining the parameters of the trajectories of targets moving in space and their location are not considered.

Thus, the search for ways to determine the parameters of movement, trajectories of the CC and their location with high accuracy, as well as the creation of appropriate radars that allow solving qualitatively new problems of airspace control are urgent.

The closest in technical essence to the claimed method is [7 - patent 2337378, RF, G01S 13/42. Method for determining the parameters of the trajectory of movement of air targets in surveillance radars / Likhachev V.P., Mubarak N.Kh. Appl. 2.07.2007, publ. 10/27/2008], taken as a prototype. It determines the parameters of the trajectory of movement (radial and tangential velocities of air targets) by coherent accumulation of echo signals reflected from the target and their special processing. As indicated in [7], the main operations of this method are:

1. Radiation of the probing signal and reception of echo signals in the observation interval, determination of their quadrature components and storing the results.

2. Estimation of the VC coordinates (slant ranges, radial and tangential velocities, azimuth angles) as a result of multichannel intercorrelation processing of the received signals.

3. Evaluation on the horizontal plane of the values of the horizontal components of the target velocity vectors and their heading angles.

4. Estimation of the parameters of the motion of the CC.

In the prototype [7], with a fixed observation time, the accuracy of determining such parameters of the CC movement as tangential and radial velocities is increased, or the required observation time is reduced at a given accuracy.

The disadvantages of the prototype are:

- replacement of the spatial movement of the VC by movement along the horizontal plane;

- the use of the values of the slant distances in determining the values of the radial and tangential components of the velocity, which introduces additional errors in the construction of trajectories of their motion;

- performing calculations of modules of values of the linear speed of the CC on the horizontal plane without taking into account the rate of change in their heights;

- the use of two components of speed in determining the values of the course angles of the VC movement;

- insufficient accuracy of solving the problems of positioning the computer center, due to the use of the rangefinder-goniometric method;

- the need to perform a large amount of calculations when measuring coordinates and parameters of the trajectories of the CC.

The authors of the present invention have not found technical solutions that provide a high viewing speed with high-precision determination of coordinates, trajectories moving in space, and their location.

The technical problem to be solved by the proposed method is to improve the accuracy of determining the parameters of motion, trajectories moving in space of the CC and their location in the survey single-position radar.

To solve this technical problem, a method of survey single-position trilateration incoherent radar of air targets is proposed, in which

provide in the radar system located at the origin of coordinates 0, the emission of probing pulses and the reception of reflected signals using a digital antenna array or an antenna array with digital signal processing and, using the Hamming weight function on the opening of this antenna array, form a monopulse group of beams in space with a common phase center,

- номера точек А₁, А₂, …, A_k траекторий, соответствующие моментам времени t₁, t₂, …, t_k, отстоящих друг от друга на период обзора заданной области пространства Т_обз,describe the position of air targets moving in space along trajectories with arbitrary dive or pitch-up angles, values: angular coordinates - azimuth β _k and elevation angle ε _k , slant ranges R _{0, k} , moduli of velocity vectors V _k and values of course angles γ _k between vectors of velocities and slope ranges, where

- numbers of points А ₁ , А ₂ , ..., A _k trajectories corresponding to the moments of time t ₁ , t ₂ , ..., t _k , spaced apart from each other for the period of survey of a given area of space T _survey ,

ensure the linearity of the direction finding characteristics of the system within the width of the monopulse group of beams Δβ _HR in azimuth and Δε _HR in elevation due to the special choice of the displacement angles β _cm and ε _{cm of} these rays from the RSL,

divide the given area of view of space into sections of size Δβ _PX in azimuth and Δε _PX in elevation and, sequentially setting the PCL of a monopulse group of beams to the centers of these areas, emit probing pulses with a repetition period T _P and receive signals reflected from air targets during the observation interval T _N at each section of the partition, carrying out a survey of a given area during T _survey ,

целей в упомянутой области обзора, измеряют и запоминают, с привязкой к единому времени, для каждой из обнаруженных воздушных целей значения наклонных дальностей R_0,k и угловых координат, вычисляемых относительно равносигнальных направлений, какstate the detection of a collection

targets in the aforementioned field of view, are measured and stored, with reference to a single time, for each of the detected air targets the values of the slant ranges R _{0, k} and angular coordinates, calculated with respect to equisignal directions, as

Where

- сигналы угловых рассогласований с выходов угловых дискриминаторов;

- signals of angular misalignments from the outputs of the angular discriminators;

- значения коэффициентов линейных членов разложений пеленгационных характеристик в ряды Маклорена по координатам β, ε при выбранных значениях β_см и ε_см.

- the values of the coefficients of the linear terms of the expansions of the direction finding characteristics in the Maclaurin series in the coordinates β, ε for the selected values of β _cm and ε _see .

According to the invention,

replace the spatial movement of each air target along a conical surface, the guide for which is the target trajectory, and the generatrix is the vector of the inclined range, by a sequence of movements along the guide polyhedral surface formed by a set of adjacent inclined triangles 0A _k A _{k + 1} with vertices at the origin and approximating the real curved conical surface,

determine the location of the target on the said guide polyhedral surface with inclined ranges R ₀ , _k , R _{0, k + 1} ,

на время его обзораrepresent the trajectories of targets by sequences of segments А ₁ , А ₂ , А ₂ А ₃ , etc., which are the bases of the mentioned adjacent triangles, and the length S _{k, k + 1 of} each of such segments is equal to the product of the target velocity module

at the time of its review

and changes in flight altitude are described by the dive or pitch-up angles ψ _k ,

значений косинусов углов между наклонной дальностью R_0,k и осями абсцисс x и ординат ycalculated for times t _k during the observation intervals T _H by

values of the cosines of the angles between the slant range R _{0, k} and the x and y axes

- номер отсчета угловой координаты на интервале T_H,Where

is the number of the angular coordinate reference on the interval T _H ,

auxiliary points B on the abscissa axis and D on the ordinate axis, spaced at a distance d from the origin, are used to form a trilateration radar system, and the distance values R _{B, k} and R _{D, k} to the target from points B and D are calculated from G

determine, using the exponential smoothing operator, their filtered values

- параметр сглаживания,Where

- smoothing parameter,

calculate and store the values of the rectangular coordinates of the targets

smooth their values with Kalman filters, calculate the smoothed values of the angular coordinates of targets

make decisions about finding the starting points of the trajectories,

form the sizes of target selection zones, limiting them:

где V_0,ср - среднее значение скорости цели,- by range at times t _{k + 1} = t _k + T _{survey by} spheres with centers at points A _{k + 1} and radii

where V _{0, cf} - the average value of the target speed,

- in azimuth and elevation by rays drawn from the origin at angles

дальностей

и координат

определяют приращения прямоугольных и угловых координат

during the second review, the values of R _{0, k + 1} , β _{0, k + 1} , ε _{0, k + 1 of the} targets are measured and the belonging of new readings to the initial sections of the trajectories of previously detected targets is determined, the angles are calculated for each tracked target

ranges

and coordinates

define the increments of rectangular and angular coordinates

extrapolated values of rectangular coordinates from the outputs of Kalman filters are used to form selection zones at points A _{k + 2} of target trajectories, according to the results of subsequent surveys, target trajectories are detected by the criterion "three out of three", that is, by the presence of three readings in three surveys

calculate the lengths of the segments traversed by the targets during T _survey ,

determine the values

- modules of target velocity vectors

- their spatial heading angles

- height increments

- and dive or pitch-up angles

их соединяющими, являющимися основаниями смежных наклонных треугольников, образующих в совокупности многогранные поверхности, аппроксимирующие упомянутые реальные криволинейные поверхности, по направляющим которых движутся воздушные цели.the coordinates of air targets are measured in subsequent surveys, the targets are tracked, and then the trajectories of their movement are plotted, determining the latter by the rectangular coordinates of the points A _k and vectors

connecting them, which are the bases of adjacent inclined triangles, forming in the aggregate polyhedral surfaces approximating the mentioned real curved surfaces, along the guides of which the air targets move.

The technical result of the proposed invention are mathematical relationships describing the method of trilateration radar, and the structure of the trilateration radar, which implements the proposed method, providing accurate determination of the location, motion parameters and trajectories of the targeted air targets.

The proposed invention is not known in modern radio engineering, and there are no known sources of information containing information about similar technical solutions that have features similar to the set of features that distinguish the claimed solution from the prototype, and also have properties that coincide with the properties of the proposed solution. Therefore, we can assume that they have significant differences, follow from them in a non-obvious way and, therefore, meet the criteria of "novelty" and "inventive step".

The essence of the invention is illustrated by the following figures:

figure 1 - the geometry of the problem in space;

figure 2 is a block diagram of a device that implements the proposed method.

When implementing the proposed method, the following sequence of operations is performed.

1. Provide in the radar system located at the origin of coordinates 0, the emission of sounding pulses and the reception of reflected signals using a digital antenna array or an antenna array with digital signal processing and, using the Hamming weight function on the opening of this antenna array, form a monopulse group of beams in space with a common phase center.

- номера точек А₁, А₂, …, A_k траекторий, соответствующие моментам времени t₁, t₂, …, t_k, отстоящих друг от друга на период обзора заданной области пространства Т_обз.2. Describe the position of air targets moving in space along trajectories with arbitrary diving or pitching angles, values: angular coordinates - azimuth β _k and elevation angle ε _k , slant ranges R _{0, k} , modules of velocity vectors V _k and values of heading angles γ _k between the vectors of velocities and slope ranges, where

- numbers of points А ₁ , А ₂ , ..., A _k trajectories corresponding to the moments of time t ₁ , t ₂ , ..., t _k , spaced apart from each other for the period of survey of a given area of space T _survey .

3. Ensure the linearity of the direction finding characteristics of the system within the width of the monopulse group of beams Δβ _HR in azimuth and Δε _HR in elevation due to a special choice of displacement angles β _cm and ε _{cm of} these beams from the RSL.

4. Divide the given area of view of space into sections with the size of Δβ _PX in azimuth and Δε _PX in elevation and, sequentially setting the equal-signal direction of the monopulse group of rays to the centers of these areas, emit probing pulses with a repetition period T _P and receive signals reflected from air targets , during the observation interval T _N at each section of the division, carrying out a survey of a given area during T _survey .

целей в упомянутой области обзора, измеряют и запоминают, с привязкой к единому времени, для каждой из обнаруженных воздушных целей значения наклонных дальностей R_0,k и угловых координат, вычисляемых относительно равносигнальных направлений, как5. State detection of aggregate

targets in the aforementioned field of view, are measured and stored, with reference to a single time, for each of the detected air targets the values of the slant ranges R _{0, k} and angular coordinates, calculated with respect to equisignal directions, as

Where

- сигналы угловых рассогласований с выходов угловых дискриминаторов;

- signals of angular misalignments from the outputs of the angular discriminators;

- значения коэффициентов линейных членов разложений пеленгационных характеристик в ряды Маклорена по координатам β, ε при выбранных значениях β_см и ε_см.

- the values of the coefficients of the linear terms of the expansions of the direction finding characteristics in the Maclaurin series in the coordinates β, ε for the selected values of β _cm and ε _see .

6. Replace the spatial motion of each air target along a conical surface, the guide for which is the target trajectory, and the generatrix is the vector of the inclined range, by a sequence of movements along the guide polyhedral surface (here the guide and the generator are the terms of stereometry for a conical surface) formed by a set of adjacent inclined triangles 0A _k A _{k + 1} with vertices at the origin and approximating a real curved conical surface.

7. Determine the location of the target on the said guide polyhedral surface by slant ranges R _{0, k} , R _{0, k + 1} .

на время его обзора8. The trajectories of the targets are represented by sequences of segments А ₁ , А ₂ , А ₂ А ₃ , etc., which are the bases of the mentioned adjacent triangles, and the length S _{k, k + 1 of} each of such segments is equal to the product of the target velocity modulus

at the time of its review

and changes in flight altitude are described by the dive or nose-up angles ψ _k .

значений косинусов углов между наклонной дальностью R_0,k и осями абсцисс x и ординат у9. Calculate for points in time t _k during observation intervals T _H by

the values of the cosines of the angles between the slant range R _{0, k} and the x and y ordinates

- номер отсчета угловой координаты на интервале T_H,Where

is the number of the angular coordinate reference on the interval T _H ,

10. Auxiliary points B on the abscissa and D on the ordinate, spaced at a distance d from the origin, are used to form a trilateration radar system, and the distance values R _{B, k} and R _{D, k} to the target from points B and D are calculated from G

11. Determine, using the exponential smoothing operator, their filtered values

- параметр сглаживания,Where

- smoothing parameter,

:that is, for point A _{1, we} calculate the smoothed range values

:

and ranges

и т.д.

etc.

12. Calculate and store the values of the rectangular coordinates of the targets

13. Smooth their values with Kalman filters, calculate the smoothed values of the angular coordinates of targets

14. Make decisions about the detection of the starting points of the trajectories.

15. Form the sizes of target selection zones, limiting them:

где V_0,ср - среднее значение скорости цели,- by range at times t _{k + 1} = t _k + T _{survey by} spheres with centers at points A _{k + 1} and radii

where V _{0, cf} - the average value of the target speed,

- in azimuth and elevation by rays drawn from the origin at angles

, дальностей

и координат

определяют приращения прямоугольных и угловых координат

16. During the second survey, the values of R _{0, k + 1} , β _{0, k + 1} , ε _{0, k + 1 of} targets are measured and the belonging of new readings to the initial sections of the trajectories of previously detected targets is determined, the angles are calculated for each tracked target

, ranges

and coordinates

define the increments of rectangular and angular coordinates

17. Extrapolated values of rectangular coordinates from the outputs of Kalman filters are used to form selection zones at points A _{k + 2} of target trajectories, based on the results of subsequent surveys, target trajectories are detected according to the criterion "three out of three", that is, by the presence of three readings in three surveys.

18. Calculate the lengths of the segments traversed by the targets during the T _survey ,

19. Determine values

- modules of target velocity vectors

- their spatial heading angles

- height increments

- and dive or pitch-up angles

, их соединяющими, являющимися основаниями смежных наклонных треугольников, образующих в совокупности многогранные поверхности, аппроксимирующие упомянутые реальные криволинейные поверхности, по направляющим которых движутся воздушные цели.20. Coordinates of air targets are measured in subsequent surveys, targets are tracked, and then trajectories of their movement are plotted, determining the latter by rectangular coordinates of points A _k and vectors

, connecting them, which are the bases of adjacent inclined triangles, forming in aggregate polyhedral surfaces approximating the mentioned real curved surfaces, along the guides of which the air targets move.

An example of a system that implements the proposed method is a survey single-position trilateration incoherent radar, the structural diagram of which is shown in figure 2, where the following designations are adopted:

1 - radar (RL);

2 - information processing device (IDU);

3 - transmitter (PRD);

4 - power divider unit (PM);

5 - block of receiving and transmitting modules (BPPM);

6 - antenna array (AR);

7 - synchronizer (CX);

8 - frequency synthesizer (MF);

9 - control device (UU);

10 - device for storing readings of the weight function (UZOVF);

11 - calculator of direction finding characteristics (DF);

12 - calculator of the angles of displacement of the maxima of the DP in the MGL from the RSI and the expansion coefficients of the function describing the HR (VUSCR);

13 - block of multipliers and data flow router (BUMPD);

14 - diagram forming device (DOU) MGL;

15 - unit of detectors and range meters (BOID);

16 - block of angular misalignment meters (BIUR);

17 - transceiver device for data exchange and signal retransmission (PPUOD);

18 ₁ , 18 ₂ - transmitting and receiving devices for data exchange and signal retransmission (PPUOD1, PPUOD2);

19 - interface device (UI);

20 - unit for forming time marks (BFMEV);

21 - block of calculator of rectangular coordinates (BVPK);

22 - block of calculator of spherical coordinates (BVSK);

23 - block of calculator of speeds, spatial heading angles and dive angles (BVSKU);

24 - block of calculator of trajectories of targets (BVTTs);

25 - block of predicted target coordinates calculator (BVPK).

Figure 2 uses additional abbreviations:

ВС - superior system,

ID - initial data,

KIS - information communication channel,

KU - management team,

PD - data stream,

SG - local oscillator signal,

SI - sync pulse,

SP - transmitter signal.

Survey single-position trilateration incoherent radar contains (figure 2) RL 1 and UOI 2, connected by a duplex CIS.

The RL 1 includes PRD 3, the output of which is connected to the input of PM 4, the outputs of which are connected to inputs 1in ... Ωin BPPM 5. Inputs-outputs 1vv ... Ωvv BPPM 5 are connected to the same inputs-outputs of AR 6, and outputs 1out ... Ω _out BPPM 5 are connected to signal inputs 1in ... Ωin BUMPD 13.

The first output of CX 7 is connected to the second input of the PRD 3, the first input of which is connected to the first output of the SCh 8, the second output of which is connected to the first control input 1u BUMPD 13, and to the second control input 2y BUMPD 13 is connected to the second output CU 9, the first output of which connected to the input of the midrange 8.

The third output of CX 7 is connected to the second input of BOID 15, and the fourth output of CX 7 is connected to the second input of PPUOD 17, to the first input of which the eighth output of CX 9 is connected. The fifth output of CX 9 is connected to the input of CX 7, and the second output of CX 7 is connected to the third control input 3u BUMPD 13. Signal output BUMPD 13 is connected to the signal input of POU 14, the first output of which is connected to the first input of BOID 15, and the second output of POU 14 is connected to the input of BIUR 16, the output of which is connected to the seventh input of CU 9. To the sixth the input of UU 9 is connected to the output of BOID 15. The third output of UU 9 is connected to the first control inputs 1u BPPM 5 and DOU 14, and the fourth output of UU 9 is connected to the second control input 2u DOU 14. The ninth output of UU 9 is connected to the sixth input of PPUOD 17, the fifth the output of which is connected to the tenth input of the control unit 9.

The eleventh output of the UU 9 is connected to the input of the UUVF 10, the first output of which is connected to the first input of the VPH 11, and the second output to the twelfth input of the UU 9. The thirteenth output of the UU 9 is connected to the second input of the VPH 11, the output of which is connected to the input of the VUSKR 12. Output VUSKR 12 is connected to the fourteenth input of UU 9.

The third input and the fourth output of the PPUOD 17 duplex KIS are connected, respectively, with the second output and the first input of the PPUOD2 18 ₂ .

The third output and the fourth input of PPUOD2 18 _{2 are} connected, respectively, to the third input and the fourth output of UI 19. To the fifth input of UI 19, the output of BFMEV 20 is connected, and the first input and second output of UI 19 are connected, respectively, to the third output and the fourth input of PPUOD 1 18 ₁ , the first entrance and the second exit of which are the border of the radar (connected to the superior system).

The radar includes again: BVPK 21, BVSK 22, BVSKU 23, BVTTs 24 and BVPK 25. The first input and second output of BVPK 21 are connected respectively to the sixth output and the seventh input of UI 19, and the first input and second output of BVSK 22 - respectively to the eighth output and the ninth input of UI 19. The first input and the second output of the BVSKU 23 are connected respectively to the tenth output and the eleventh input of the UI 19, and the first input and the second output of the BVTTs 24 are, respectively, to the twelfth output and the thirteenth input of UI 19. In this case, the first input and the second output of BVPK 25 is connected, respectively, to the fourteenth output and the fifteenth input of UI 19.

Survey three-coordinate single-position trilateration radar works as follows.

After turning on the power supply, the control command from the first output of the control unit 9 of the radar 1 is fed to the midrange 8, where a signal is generated for the transmitter, which is fed from the first output of the midrange 8 to the first input of the PRD 3, and the local oscillator signal, which from the second output of the midrange 8 goes to the first control entrance 1u BUMPD 13.

The geometry of the problem is shown in figure 1, where at point 0 there is RL, and at the starting point A ₁ - located VC; then the VC moves on the trajectory sections under consideration in a straight line and uniformly with an arbitrary dive (pitching) angle at a height H _k above the ground surface, which is considered flat. If the trajectory of the target is curvilinear, then its piecewise-linear approximation is carried out. The target EC moves in space with a velocity V, which is the modulus of the velocity vector V.

In the above-mentioned radar 1, a digital AA or antenna array with digital signal processing is used and, using the Hamming weighting function on its opening, a monopulse group of beams with a common phase center is formed in space. The values of the special displacement angles β _cm and ε _{cm of the} maxima of the direction finding in the MGL from the RSL are selected and the data is sent from the fourth output of the UU 9 to the second control input 2u of the DOU 14, providing, as shown in [2], the linearity of the direction finding characteristics of the radar 1 in the working zones Δβ _PX in azimuth and Δε _PX in elevation, covering the entire width of the MGL. The readings of the WF and the coefficients of the expansion of the function describing the HR are sent to the same input 2u DOU 14.

From the second output of UU 9, control commands are sent to the second control input 2u BUMPD 13. Similar control commands are sent from the third output of UU 9 to the first control inputs 1u BPPM 5 and DOU 14.

According to the control commands coming from the fifth output of the CX 9 to the input of CX 7, from the first output of CX 7 to the second input of the PRD 3, sync pulses are supplied; similar sync pulses are supplied from the second output of CX 7 to the third control input 3u BUMPD 13, from the third output of CX 7 to the second input of BOID 15 and from the fourth output of CX 7 to the second input of PPUOD 17.

TX 3 generates sounding pulses which are fed through PM4 to inputs 1vh ... Ω _Rin BPPM 5, wherein the pulses are amplified in the channel power amplifiers and, after passing through the channel circulators act to inputs-outputs 1 _cc ... Ω _centuries in the AP 6, antenna elements of which emit probing pulses into a given area of space.

The signals reflected from the located VCs are received by antenna elements from the AR 6 and sent to the BPPM 5, each module of which contains a circulator, a low-noise amplifier (LNA) and an analog-to-digital converter (ADC). From the input of the module, the signal through the circulator enters the channel LNA and is then converted to an intermediate frequency, and then subjected to analog-to-digital conversion. From outputs 1 _out … Ω _out BPPM 5 samples of the mixture of echo signals and noises are fed to signal inputs 1 _in … Ω _in BUMPD 13, where the corresponding data stream is formed. It is sent from the output of the BUMPD 13 to the signal input of the DOU 14, where it is weighted by multiplying it by the counts of the Hamming weighting function W (x, y). These readings are taken from the UZOVF 10 device by a control command from the eleventh output of the UU 9, and are fed from the second output of the UUVF 10 to the twelfth input of the UU 9.

From the first output of UZOVF 10, the VF readings are also fed to the first input of VPH 11, to the second input of which ID is received from the thirteenth output of the UU 9. The values of PX are sent from the output of VPH 11 to the input of VUSKR 12, where the angles of displacement of the maxima of the DP in the MGL from the RSN are calculated, which, together with the expansion coefficients of the function describing the PX, are fed to the fourteenth input of the control unit 9.

по азимуту и

по углу места, обеспечивая в моноимпульсном РЛ 1 линейные ПХ с размером Δβ_ПХ по азимуту и Δε_ПХ по углу места, соответственно.In DOU 14, a monopulse group of beams with a common phase center is formed, consisting of two pairs of beams displaced from the PCN by angles

in azimuth and

in elevation, providing in a monopulse RL 1 linear HR with the size Δβ _HR in azimuth and Δε _HR in elevation, respectively.

When a total signal arrives from the first output of the DOU 14 to the first input of the BOID 15, it is determined, taking into account the sync pulse from the third output of the CX 7 arriving at the second input of the BOID 15, the time delay of the echo signals and the range to the sighted targets. These data from the output of the BOID 15 are sent to the sixth input of the CU 9.

The space survey is carried out by scanning the MGL, for which the given area of the space survey is divided into (L + 1) × (N + 1) sections with the size of each Δβ _PH along the azimuthal direction and Δε _PH along the elevation directions. Then, sequentially installing the PCN of a monopulse group of rays in the centers of the sections

- номера участков разбиения по азимуту и углу места соответственно, осуществляют дискретный обзор упомянутой области обзора. В течение интервала наблюдения Δt на каждом участке разбиения производят обнаружение всей совокупности

лоцируемых целей.Where

- the numbers of the sections of the division in azimuth and elevation, respectively, carry out a discrete survey of the mentioned field of view. During the observation interval Δt at each section of the partition, the entire set is detected

target targets.

From the second output of the DOU 14, the values of the angles of deviation from the RSN are fed to the input of the BIUR 16, where the values of the increments of azimuths and elevation angles are calculated, which from the output of the BIUR 16 are fed to the seventh input of the CU 9. It is stored in it, with reference to the universal time system when using the data BFMEV 20, for each of the detected targets, the values of the readouts of the oblique ranges and angular coordinates calculated relative to the RSN as a result of solving the corresponding linear equations using the coefficients of the linear parts of the expansions of the HX in Maclaurin series as functions of the angles β _cm , ε _cm .

The results of measuring the ranges and CC targets on the control command coming from the ninth output of the CU 9 are sent via the information communication channel from the PPUOD 17 device through the PPUOD2 18 ₂ to the UI 19, and then to the BVPK 21, in which the values of the rectangular coordinates of the CC are calculated. The same results are fed to BVSK 22, in which the parameters of the VC movement on inclined planes are determined. On the basis of the data calculated in BVSK 22 on the angles C _{k + 1, k} on inclined planes and the path lengths S _{k + 1, k} , traversed by the EC during the survey, in the BVSKU 23 spatial heading angles γ _k and dive angles ψ _{k are} determined.

Further, in BVTTS 24, curvilinear trajectories of movement of the sighted targets are built, approximating them with a set of segments S _{k + 1, k} , S _y , and in BVTC 25 - the predicted coordinates of the VC. These data are sent through PPUOD1 18 ₁ to the higher-level system.

The proposed method, based on measuring the spherical coordinates of the VC and calculating additional ranges R _{B, k} , R _{D, k} and angles c _{k + 1, k} , provides:

- determination of rectangular coordinates of the CC and their increments,

- calculation of the lengths of segments of trajectories of targets between points A _k and A _{k + 1}

- their use to approximate the trajectories of the CC,

- calculating the values of the modules of the target velocity vectors

- determination of the values of spatial heading angles

- determination of the values of the angles of diving or pitching up

и

СКП вычисления модулей скоростей целей и курсовых углов определяются формуламиThe root-mean-square errors (RMS) of calculating the values of the parameters of the movement of targets are determined by the values of errors in measuring the ranges σ _R and angular coordinates σ _β , σ _ε . When conditions are met

and

SKP for calculating the modules of target velocities and heading angles are determined by the formulas

γ_k=45°, T_обз=10 сек, c_k+1,k=10° и

относительные значения СКПAt values

γ _k = 45 °, T _survey = 10 sec, s _{k + 1, k} = 10 ° and

relative RMS values

do not exceed 10 ^-2 .

The prototype uses the formulas to determine the values of these parameters

In this case, the SKP definitions of the parameters are

and for ⏐V _k ⏐ = 300 m / s, γ _k = 45 ° we have

Consequently, the proposed method provides an increase in the measurement accuracy of the VC velocity modules and their spatial heading angles by 5 and 8 times, respectively.

For a comprehensive assessment of the quality of the proposed method, we will compare the value of the UPC for target positioning by the prototype method and the proposed method.

и конической поверхности, образующей которой является наклонная дальность R_0,k, а угол при вершине равен σ_УК [8 - Кондратьев B.C., Котов А.Ф., Марков Л.Н. Многопозиционные радиотехнические системы. - М.: Радио и связь, 1986. 264 с]. СКП местоопределения в этом случае, при

равнаIn the prototype method, the location of targets is found as the area of intersection of a spherical surface of radius R _{0, k} with wall thickness

and a conical surface, the generatrix of which is the inclined range R _{0, k} , and the angle at the apex is equal to σ _UK [8 - Kondrat'ev BC, Kotov AF, Markov LN. Multi-position radio engineering systems. - M .: Radio and communication, 1986. 264 s]. In this case, with

equals

In the proposed method, the location of targets is located as the area of intersection of three spheres [9 - Bakulev P.A. Radar systems. - M .: Radiotekhnika, 2007. 376 s] with centers at points 0, B, D and radii R ₀ , R _B , R _D , and the UPC of position

- СКП расчета дальности

Where

- UPC range calculation

- параметр сглаживания;

- smoothing parameter;

- угол между дальностями R_0,k и R_B,k на наклонной плоскости 0A_kB_k;

- the angle between the ranges R _{0, k} and R _{B, k} on the inclined plane 0A _k B _k ;

- угол между дальностями

на наклонной плоскости DA_kx_k,

- the angle between the ranges

on an inclined plane DA _k x _k ,

σ_УК=0,3°, R₀=10⁵ м, ϕ=11°30', ϕ₁=17°30', d=2×10⁴ м, β_k=ε_k=45°, α=0,2 имеем

σ_МОСП=735 м, σ_МОПС=141,84 м. При этом отношение СКП способа-прототипа и предложенного способа составляет

In the case when

σ _UK = 0.3 °, R ₀ = 10 ⁵ m, ϕ = 11 ° 30 ', ϕ ₁ = 17 ° 30', d = 2 × 10 ⁴ m, β _k = ε _k = 45 °, α = 0 , 2 we have

_ISS σ m = 735, σ = 141.84 m _MOPS. The ratio of CSP method-prototype and the proposed method is

The implementation of the proposed method does not encounter difficulties at the current level of development of radio engineering and devices for analog and digital signal processing. The possibility of implementing the proposed method provides him with the criterion of "industrial applicability".

Compared with the prototype, the use of the operations of the proposed method provides for the determination of the location of air targets with mean square errors less than 5.18 times, and also:

- 5 times increase in the accuracy of measurements of modules of vectors of air targets' velocities;

- 8 times increase in the accuracy of measurements of the spatial heading angles of the VC.

The results obtained make it possible to ensure, based on the use of accurately measured distances to the VC, the selection of individual elements of group targets moving in space and the separate construction of their trajectories.

Claims (47)

The method of survey single-position trilateration incoherent radar of air targets, in which in the radar system located at the origin of coordinates 0, the emission of sounding pulses and the reception of reflected signals are provided using a digital antenna array or an antenna array with digital signal processing and using a weight on the opening of this antenna array Hamming function, form in space a monopulse group of rays with a common phase center, describe the position of air targets moving in space along trajectories with arbitrary dive or pitch-up angles, values: angular coordinates - azimuth β _k and elevation angle ε _k , slant ranges R _{0, k} , moduli of velocity vectors V _k and values of course angles γ _k between vectors of velocities and slope ranges, where

- numbers of points А ₁ , А ₂ , ..., А _k trajectories corresponding to the moments of time t ₁ , t ₂ , ..., t _k , spaced from each other for the period of survey of a given area of space T _survey , ensure the linearity of the direction finding characteristics of the system within the width of the monopulse group of beams Δβ _PX in azimuth and Δε _PX in elevation due to a special choice of displacement angles β _cm and ε _{cm of} these beams from the equisignal direction, divide the given area of the space view into sections of size Δβ _PX in azimuth and Δε _PX in elevation and, sequentially setting the equisignal direction of the monopulse group of rays to the centers of these areas, emit probing pulses with a repetition period T _P and receive signals reflected from air targets in the course of the observation interval T _N in each section of the partition, carrying out a survey of a given area during the time T _survey , state the detection of a collection

targets in the aforementioned field of view, are measured and stored, with reference to a single time, for each of the detected air targets the values of the slant ranges R _{0, k} and angular coordinates, calculated with respect to equisignal directions, as

Where

- signals of angular misalignments from the outputs of the angular discriminators;

- the values of the coefficients of the linear terms of the expansions of the direction finding characteristics in the Maclaurin series in the coordinates β, ε for the selected values of β _cm and ε _cm , characterized in that replace the spatial movement of each air target along a conical surface, the guide for which is the target trajectory, and the generatrix is the vector of the inclined range, by a sequence of movements along the guide polyhedral surface formed by a set of adjacent inclined triangles 0А _k А _{k + 1} with vertices at the origin and approximating the real curved conical surface, determine the location of the target on the said guide polyhedral surface with inclined ranges R _{0, k} , R _{0, k + 1} , represent the trajectories of targets by sequences of segments А ₁ А ₂ , А ₂ А ₃ , etc., which are the bases of the mentioned adjacent triangles, and the length S _{k, k + 1 of} each of such segments is equal to the product of the target velocity modulus ⏐V _k ⏐ by its time review

and changes in flight altitude are described by the dive or pitch-up angles ψ _k , calculated for the moments of time t _k during the observation intervals T _N according to

values of the cosines of the angles between the slant range R _{0, k} and the x and y y-axes

Where

- number of reference of the angular coordinate on the interval T _H , auxiliary points B on the abscissa axis and D on the ordinate axis, spaced at a distance d from the origin, are used to form a trilateration radar system, and the distance values R _{B, k} and R _{D, k} to the target from points B and D are calculated from G

determine, using the exponential smoothing operator, their filtered values

Where

- smoothing parameter, calculate and store the values of the rectangular coordinates of the targets

smooth their values with Kalman filters, calculate the smoothed values of the angular coordinates of targets

make decisions on the detection of starting points of trajectories, form the sizes of target selection zones, limiting them: - by range at times

- spheres with centers at points А _{k + 1} and radii

where V _{0, cp} is the average value of the target speed, - in azimuth and elevation - by rays drawn from the origin at angles

during the second review, the values of R _{0, k + 1} , β _{0, k + 1} , ε _{0, k + 1 of the} targets are measured and the belonging of new readings to the initial sections of the trajectories of previously detected targets is determined, the angles are calculated for each tracked target

,

ranges

and coordinates

define the increments of rectangular and angular coordinates

use extrapolated values of rectangular coordinates from the outputs of Kalman filters to form selection zones at points A _{k + 2} target trajectories, according to the results of subsequent surveys, target trajectories are detected according to the "three out of three" criterion, that is, according to the presence of three counts in three surveys, calculate the lengths of the segments traversed by the targets during T _survey ,

determine the values - modules of target velocity vectors

- their spatial heading angles

- height increments

- and dive or pitch-up angles

the coordinates of air targets are measured in subsequent surveys, the targets are tracked, and then the trajectories of their movement are plotted, determining the latter by the rectangular coordinates of the points A _k and vectors

, connecting them, which are the bases of adjacent inclined triangles, forming in aggregate polyhedral surfaces approximating the mentioned real curved surfaces, along the guides of which the air targets move.

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