RU2796428C1 - Device and method for reducing the probability of false paths and automatic adaptation of the secondary radar to the installation site - Google Patents

Abstract

FIELD: air traffic control.

SUBSTANCE: used in secondary radar to reduce the probability of initialization of false tracks. Re-reflective zones are detected using continuously incoming radar information, which is analyzed for reliability, taking into account the duration of the tracks, their beginning and end relative to the visibility limits for the flight altitude of the detected aircraft (AC), taking into account the presence of airports where the aircraft trajectories can begin and end, the presence within the visibility zone of the border with neighboring automated air traffic control systems (ATM-AS), the presence of closing angles, the presence of duplicated information in the forms, as well as the deterioration in the accuracy of determining the AC angular coordinates. The formed zones of re-reflections, when assessing the possibility of establishing new traces, help to speed up the process of detecting illegitimate traces. Tracks whose beginning does not coincide with the re-reflection zones are considered legitimate. When a new track appears inside the multipath zone, the track beginning is checked for coincidence with the end of the runway, if it exists inside the multipath zone, and if the track beginning does not coincide with the runway end, the track beginning is checked for coincidence with the boundary of the ATM-AS coverage area, if it passes through the multipath zone or coincides with the boundary of the multipath zone, if the track beginning coincides with the runway end or the boundary of the ATM-AS coverage area, the track is considered legitimate. In the course of operation, with the appearance of new reflective surfaces, new zones of re-reflections are created or existing zones are expanded. The boundaries of new re-reflection zones are used to identify illegitimate tracks, so that new false tracks do not appear on the control indicator and are not broadcast to the ATM-AS.

EFFECT: increase in flight safety due to an increase in protection against re-reflected signals.

2 cl, 2 dwg

Description

The field of technology to which the invention belongs

The invention relates to the field of air traffic control and can be used in secondary radar to reduce the likelihood of false tracks and automatic adaptation of the radar to the installation site, as well as adaptation during operation when artificially erected reflectors appear (buildings, technical structures, hangars, etc. .).

State of the art

Known analogues of the proposed method [1 patent No. 2225624, 2 patent No. 2348053], where the problem of reducing the probability of tying false tracks is solved by processing radar information and can be used in coherent-pulse radar stations (radar) tracking for recognition of air decoys (LC) any types against the background of real ones. The solution of the problem of recognition of the LC is proposed to be carried out by two radar stations spaced apart on the ground, the main and additional in two stages.

These methods are characterized by a large redundancy of equipment, which leads to a significant increase in cost.

The closest in technical essence to the proposed method is a well-known method of processing radar information with a low probability of setting up false tracks (patent No. spatio-temporal processing is supplemented by the operation of generating a false alarm sign (LT), which performs the selection of the maximum amplitude value of the moving target signal, optimal processing of local object signals, data accumulation, multiplication by a coefficient depending on the stability of the transceiver path, comparison of the delayed maximum amplitude value of the moving target signal targets with the residual level from the signal of local objects and determining the sign of LT, while the sign of LT takes a non-zero value if the level of the residual from the signal of local objects exceeds the delayed maximum amplitude value of the signal of the moving target and zero - otherwise. Next, the generated LT feature is used in trace processing, which accumulates the values of spatial coordinates, the radial velocity, and the LT feature over several surveys, and targets with a non-zero value of this feature are excluded from consideration when starting the route, and when tracking, the target selection priority is reduced (if there are several goals).

The advantage of this method is to reduce the probability of false initialization of tracks arising from reflective surfaces.

The prototype "Method for reducing the probability of setting false traces" (patent No. 2586623) provides an example of a device that implements this method for reducing the probability of setting false tracks, mainly consisting of a space-time processing system, a maximum amplitude value selection unit, a data accumulation unit for several surveys, a block for linking traces and a block for generating a sign of a false alarm (LT). The formation of the LT feature allows to take into account the decrease in the reliability of measuring the spatial coordinates and the radial velocity of the DC, which has a non-zero value of this feature, makes it possible to screen out the LT at the level of the route tie-in, which reduces the time for making a decision on the elimination of a false track.

The amplitude false alarm generation method proposed in the considered method is most effective for primary radars; it is useful in secondary radar, but does not solve all the problems associated with reflections. In secondary radar, situations are very often encountered in which the amplitude of the reflected signal differs little from the amplitude of the direct signal, and it is difficult to separate them by comparing the amplitudes. It is known that the most dangerous situation for secondary radar is the situation when the interrogation signal is reflected from some reflective surface, the reflected request is received by the transponder of the aircraft and emits a response, which in turn, reflected from the same reflective surface, enters the radar receiver. These situations occur quite often, the difficulty of resolving them lies in the fact that a false response form occurs at the azimuth of the reflecting surface, and not at the azimuth of the responding aircraft, while the probability that the amplitudes of these signals will differ slightly from each other is quite high. If at the same time the information component of the reflected answers is distorted, then the amplitude method is not effective.

The situation in which the request and the response are reflected from the same reflective surface was the main reason for the creation of the proposed method and device. This method and apparatus is used in addition to the known secondary radar (SRL) protection against receiving false signals, one example of which is the dynamic detection threshold, which is useful when we are dealing only with a reflected response.

Disclosure of the essence of the invention

The invention relates to the field of air traffic control and can be used in secondary radars to reduce the likelihood of false paths and to automatically adapt the secondary radar of A/C/S modes, ATC to the location, during installation, after installation and during operation, with the appearance of artificially erected reflectors (buildings, technical structures, hangars, etc.).

The objective of the proposed method and device is to improve flight safety by increasing the protection against re-reflected signals.

This problem is solved due to the fact that when initializing tracks from aircraft, a device is used that implements a method that includes detecting multipath zones and prohibiting the initialization of tracks starting inside multipath zones, except for the cases indicated below.

According to the invention, a method for processing radar information with a low probability of false paths and automatic adaptation of the secondary radar to the installation site includes the following steps:

a) setting the blocking time of the data flow directly to the solver until the reflection zone mapping is completed;

b) space-time processing;

c) false trace initialization inhibit operation;

d) the operation of forming zones of reflections;

In the proposed method:

at step b) perform the data preparation operation, which includes the operation of excluding from consideration traces that were not at the visibility boundary at the moment of switching on,

performing a spatial verification operation, including the operation of determining the location of the first route logs relative to the boundaries of the visibility zone, relative to the closing angles, relative to the funnel, relative to the ends of the runways, if any;

after step b), if the location of the first forms coincides with the boundaries indicated in b), the traces are tied, if the location of the first trace forms does not coincide with the boundaries indicated in b), an information verification operation is performed, which includes the operation of comparing the information component of the initialized forms routes with the information component of the forms of previously initialized routes, but currently existing, for the presence of duplicated data in them, in the presence of which, in particular, in the presence of a duplicated side number, the operation of determining the location of the first forms of routes relative to the borders with neighboring automated air traffic control systems ( AC-ATC), if they coincide with the boundaries, allow the tying of tracks, if not, perform the operation of calculating the zones of reflections, the operation of forming the archive of the zones of reflections, the operation of determining whether the initialized tracks belong to the zones of reflections and the operation of converting coordinates into the WGS-84 format to display the zones reflections on the control indicator.

According to the invention, a device for reducing the probability of false traces and automatic adaptation of the secondary radar to the installation site includes a spatio-temporal processing system, a trace initiation unit. The device additionally contains:

archive of parameters of initialized traces; information feature verification block; block for calculating zones of re-reflections; archive of reflection zones; decision block; track tying block; the output of which is the output of the device; a coordinate converter to the WGS-84 format, the first input of which is connected to the archive of reflection zones and the first output of which is the output of the device; archive of closing angles and archive of height limits of visibility,

moreover, the output of the initialized traces parameters archive is connected to the second input of the information features verification block, the first output of the information features verification block is connected to the multipath zones calculation unit, the first output of the multipath zones calculation unit is connected to the first input of the multipath zones archive, the first output of the multipath zones archive is connected to the first the input of the decision block and the first output of the decision block is connected to the second input of the route tying block,

wherein the space-time processing system is supplemented with a data preparation unit, the first input of which is the input of the device and the first output of which is connected to the first input of the space-time processing unit; the second output of the data preparation unit is configured to connect to the fourth input of the decision block only after the completion of the formation of the map of the re-reflections zones, and the third input of the space-time processing unit is configured to be connected to the first output of the closing angles archive; and the second input of the spatio-temporal processing unit is connected to the first output of the archive of altitude boundaries of visibility.

The proposed method and device provide a technical result, which consists in reducing the probability of initialization of the routes, as well as in the automatic adaptation of the radar to the installation site and adaptation during operation when artificially erected reflectors appear (buildings, technical structures, hangars, etc.).

Brief description of the drawings

Fig. 1 - the algorithm of the method for reducing the probability of tying false tracks and automatically adapting a monopulse secondary radar to the installation site;

Fig. 2 is a block diagram of a device according to the invention.

Implementation of the invention

The implementation of the method is carried out as follows: at the moment of switching on the SSR, the forms of aircraft further (AC) are excluded from the procedure for forming reflection zones, which at the time of switching on the SSR were not at the altitude boundary of the SSR visibility zone. From the moment of initial switching on of the monopulse secondary radar (MSSR) until the end of the time set by the operator, the duration of which is associated with the completion of the formation of the map of the zones of reflections, the higher the intensity of air traffic, the faster the map of the zones of reflections will be formed, the presence of which will reduce the time for detecting false tracks . In the process of forming zones of re-reflections from the flow of radar information, paths are identified, the beginning of which coincides with the altitude boundary of visibility of the SSR. Tracks, the first forms of which start from the altitude boundary of the visibility zone, are used to initialize the tracks and transfer their parameters to the automated air traffic control system (AC-ATC). Routes, the beginning of which does not coincide with the altitude boundaries of the visibility zones, are subjected to a check for the coincidence of the first forms of these routes with the ends of the runways, if any, are present in the SSR coverage area. If the beginning of the tracks coincides with the ends of the runways, their parameters can also be used to start tracks that will be broadcast to AC-ATC. If the beginning of the routes do not coincide with the ends of the runways, a check is made for the matching of the missing parts of the routes with the closing angles or funnel. If the corners of the closure or funnel coincide with the missing part of the track, the forms of these routes are used to tie the tracks and broadcast to AC-ATC. If the corners of the closure or funnel do not match the missing part of the track, the presence of information signs of re-reflections in the track forms is checked, which can be used as the following:

- lack of additional information;

- unstable reception of additional information;

- distortion of additional information from form to form. If such signs are present, trace initialization is prohibited,

and the geometric parameters of the track are used to calculate the zones of reflections. If there are no such signs, it is checked, according to the archive of initialized tracks, that the track logs contain the side number that already exists for the track formed earlier, but still exists, if there is no duplicate side number in the track logs, the first logs of these routes are checked for a match, with the boundary of the AC-ATC coverage area. If the appearance of the first logs does not coincide with the AC-ATC boundary, then the track geometry is used to calculate the multipath areas. And if the first forms coincide with the AC-ATC boundary, then the forms of these routes are used to link tracks and translate their parameters into AC-ATC. If a duplicate board number has been found in the track logs, a check is made for the simultaneous presence of tracks with the same board number within the same AC-ATC zone. If the tracks are in the area of the same AC-ATC, the geometry of the duplicated track is used to calculate the reflection area, and the initialization of such a track is prohibited. If the duplicated track and the track that previously existed are in different AC-ATC zones, then a check is made for the coincidence of the first records of the duplicated track with the boundary of the neighboring ATC station, if the first records of the track coincide with the boundary of the neighboring ATC station, initialization of the route and transmission of parameters to the AC is allowed -ATC. If the first track logs do not match the boundary of the AC-ATC served by this SSR, then the geometric data of this track are used to construct multipath zones. After the time selected for the formation of reflection zones, the flow of radar information is divided into two directions, the data flow from the first direction ceases to influence the paths, its task is to form new zones of reflections or expand existing ones in cases where new reflective surfaces appear. The flow of radar information from the second direction will provide the connection of routes. In this direction, the flow of information from the data processor is checked for the coincidence of the first track logs with the already formed multipath zones, the tracks, the first logs of which do not fall into the multipath zone, are used to start routes, and their data is sent to AC-ATC. Tracks, the first forms that fall into the zones of re-reflections, are checked for the presence of information signs of re-reflections in them, if any, the initialization of the tracks is prohibited. If there are no information signs, a check is made for the coincidence of the first track logs with the ends of the runways, if the first track logs match with the ends of the runways, then their parameters are used to initialize the route and data about it are transmitted to AC-ATC. If the first track logs do not coincide with the ends of the runways or the runways are not in the multipath zone, then the first track logs are checked for coincidence with the boundaries of the AC-ATC coverage area, if the first track logs start from the AC-ATC coverage area boundary, route initialization is allowed and its parameters are broadcast to AC-ATC. If the first track logs do not coincide with the boundary of the AC-ATC coverage area, it is prohibited to initialize the routes and broadcast their data to the AC-ATC.

The operation algorithm of the method for reducing the probability of false traces and automatic adaptation of a monopulse secondary radar to the installation site is shown in Fig. 1.

The proposed device for reducing the probability of false paths and automatic adaptation of the secondary radar to the installation site, the block diagram of which is shown in Fig. 2, consists of the following elements:

- spatio-temporal processing system (1);

- data preparation unit (2);

- block of space-time processing (3);

- archive of closing angles (4);

- archive of high-altitude visibility limits and AS-ATC boundaries (5);

- archive of parameters of initialized tracks (6);

- block of verification of information signs (7);

- block for calculating zones of re-reflections (8);

- decision block (9);

- archive of reflection zones (10);

- Block of tying tracks (11);

- coordinate converter to WGS-84 format (12).

The device operates as follows: the first input of the data preparation unit of the spatio-temporal processing system, from the data processor, receives a stream of secondary radar information in real time. The data preparation unit excludes from the procedure of formation of zones of re-reflections the forms of aircraft further (AC), which at the time of switching on the SSR were far from the altitude boundary of the SSR visibility zone. In addition, it blocks the entry of data that has not passed verification for compliance with the features of reflections to the decision block until a map of the reflection zones is created. The blocking time for data output can be changed by the operator with commands from the local SSR terminal. From the first output of the data preparation unit, the radar information is continuously supplied to the first input of the space-time processing unit included in the space-time processing system. From the second output of the data preparation unit, the radar information, after the completion of the map of the reflection zones, will be sent to the sixth input of the decision block, the time of creating the map is measured in days and weeks, it is set by the operator, taking into account the intensity of air traffic, at the time of the initial activation of the SSR at the operation site. The second input of the spatio-temporal processing block is connected to the archive of altitude boundaries of visibility, using the data of which the coincidence of the first track forms with the boundary of the visibility zone is checked, the third input of the spatio-temporal processing block is connected to the archive of closing angles, using the data of which the coincidence of the missing ones is checked. track parts with closing angles. The parameters of the tracks, the beginning of which coincides with the height boundaries of the visibility zones, are considered legitimate and are transferred from the first output of the space-time processing block to the decision-making block. Tracks, the beginning of which does not coincide with the height boundaries of the visibility zones, and the missing part of them is overlapped by the closing angles, are considered legitimate and their forms are transferred from the first exit to the decision-making block. All other tracks are transmitted from the second output of the spatio-temporal processing block to the first input of the information feature verification block, which evaluates the presence of information features, the instability of the presence of additional information in the received forms, the absence of additional information in the forms or the ambiguity of additional information in the forms of one track . If the above features are detected, then the geometric parameters of such tracks are sent from the first output of the information feature verification block to the first input of the multipath zone calculation block. The rest of the tracks, using the information from the archive of the parameters of the initialized tracks coming to the second input, the block for verifying information signs, are checked for the presence in the forms of data that are present in the forms of previously initialized tracks, but still exist at the moment. If duplicated data is detected, the information feature verification unit checks such tracks for their simultaneous existence within the same AC-ATC zone, the geometric parameters of the duplicated tracks that are inside the same AC-ATC zone are transmitted from the first input to the multipath zone calculation unit. Non-duplicated tracks that do not have information signs of re-reflections and are duplicated in the areas of different AC-ATCs are checked for the coincidence of their first forms with the border between the coverage areas of neighboring AC-ATCs. If the first forms do not coincide with the border between the coverage areas of neighboring AC-ATCs, then the geometric parameters of these tracks from the first output of the information feature verification block are translated to the first input of the multipath zone calculation block, and all other tracks, from the second output of the information feature verification block are translated into a decision block for linking routes and transmitting data about them to AC-ATC. The multipath zones, from the first output of the multipath zone calculation unit, are fed to the first input of the multipath zone archive, from the first output of which, immediately after the end of the predetermined time for creating a map of the multipath zones, they are fed to the first input of the decision block. The second output of the archive of reflection zones is connected to the first input of the coordinate converter to the WGS-84 format (12). Until the map of multipath zones is created, the decision block controls the route linking unit according to the data coming from the second and third inputs, but as soon as the map of multipath zones is created, the second and third inputs are blocked and radar information enters it through the fourth input, at the same time its first input is opened, as a result of which the archive of the reflection zones becomes available. When the decision block receives the form data of the newly initialized track from the preparation block, the decision block checks the very first forms to see if they fall into the re-reflect zone using the re-reflect zone map obtained from the first input. If the first forms do not fall into the re-reflection zones, the decision-making block issues a command through the first exit to the trace binding block to allow the initialization of this track. If the first logs of the newly initialized track fall into the multipath zone, and in the multipath zone the first logs start from the end of the runway, the decision block gives a command to initialize this route and transmit data about it to AC-ATC. If the first track logs do not coincide with the ends of the runways, or if there is no airport in the reflection zone from which the aircraft takes off or land, the decision block checks whether the first track logs match the boundary of the AC-ATC coverage area. If the first track logs coincide with the boundary of the AC-ATC coverage area, the decision block issues a command to the route initiation block to allow the initialization of this route and the issuance of data about it to AC-ATC. If the first track logs do not coincide with the AC-ATC coverage area boundary, the decision block prohibits route initialization and transmission of its data to AC-ATC. From the second output of the multiple reflection zones archive, information about the multiple reflection zones is fed to the input of the coordinate converter in the WGS-84 format, the output of which is connected to the control indicator, which makes it possible to observe the multiple reflection zones on the screen of the control indicator. The first inputs of the archive of high-altitude visibility limits, the archive of parameters of initialized tracks and the archive of closing angles are connected to the local terminal, which can be used to enter additional information that may arise during the operation of the radar.

The proposed device can be implemented both at the software level and at the hardware and software level using programmable logic.

Bibliography

1. Handbook on the basics of radar technology, V.V. Druzhinin, Military Publishing House, 1967

2. Gerasimov Sergey Nikolaevich, Lukyanov Sergey Fedorovich, Pachina Nadezhda Vladimirovna, patent No. 2586623 for the invention "Method for processing radar information with a low probability of setting false tracks."

3. Babusenko Sergey Ivanovich, Zhuravlev Alexander Viktorovich, Kiryushkin Vladislav Viktorovich, Krasov Evgeny Mikhailovich, Markin Viktor Grigoryevich, Shuvaev Vladimir Andreevich, patent No. 2734233 for the invention "Device for compensating direct and reflected from a stationary object radar signals of a radio transmitter in the receiver of a bistatic radar system."

4. Mitrofanov Dmitry Gennadievich, Bortovik Vitaly Valerievich, Safonov Alexey Viktorovich, Silaev Nikolai Vladimirovich, Ermolenko Viktor Pavlovich, Prokhorkin Alexander Gennadievich, Mayorov Dmitry Alexandrovich, patent No. 2348053 for the invention "Method of recognizing false air targets".

5. Mitrofanov D.G., Bortovik V.V., Nikolaev A.V., Safonov A.V., Zotov M.Yu., Mitrofanov A.D., Bochkarev A.V. patent No. 2225624 for the invention "Method of recognizing a false air target in two-position sounding".

6. Philippe Billot (FR), Denis Crevo (FR), Claude de Volder (FR), Lionel Larzhiyer (FR) patent No. 2138062 for the invention "Method and device for filtering responses from radar transponders".

Claims (10)

1. A method for processing radar information, which includes the following steps: a) space-time processing; b) false trace initialization inhibit operation, characterized in that at step a) set the blocking time of the data flow directly to the decision device until the completion of the formation of the map of zones of re-reflections, perform the data preparation operation, which includes the operation of excluding from consideration the traces that were not at the visibility boundary at the moment of switching on, perform the spatial verification operation, including the operation of determining the location of the first route logs relative to the boundaries of the visibility zone, relative to the closing angles, relative to the funnel, relative to the ends of the runways, if any; And after step a), if the location of the first trace logs does not coincide with the boundaries specified in a), an information verification operation is performed, which includes the operation of comparing the information component of the logs of initialized traces with the information component of the logs of previously initialized traces, but currently existing, on the presence of a duplicated side number in them, in the presence of which the operation of determining the placement of the first forms of routes relative to the borders with neighboring automated air traffic control systems (AC-ATC), if any, is performed, in addition, the operation of calculating the multipath zones is performed, the operation of forming archiving of the multipath zones, an operation for determining whether the initialized tracks belong to the re-reflection zones; and an operation for converting coordinates into the WGS-84 format to display the re-reflection zones on the control indicator. 2. A device for reducing the probability of setting up false traces, including a spatio-temporal processing system, a block for setting up traces, the output of which is the output of the device, characterized in that the device additionally contains: archive of parameters of initialized traces; information feature verification block; block for calculating zones of re-reflections; archive of reflection zones; decision block; a coordinate converter to the WGS-84 format, the first input of which is connected to the archive of reflection zones and the first output of which is the output of the device; archive of closing angles and archive of height limits of visibility, moreover, the output of the initialized traces parameters archive is connected to the second input of the information features verification block, the first output of the information features verification block is connected to the multipath zones calculation unit, the first output of the multipath zones calculation unit is connected to the first input of the multipath zones archive, the first output of the multipath zones archive is connected to the first the input of the decision block and the first output of the decision block is connected to the second input of the route tying block, wherein the space-time processing system is supplemented with a data preparation unit, the first input of which is the input of the device and the first output of which is connected to the first input of the space-time processing unit; the second output of the data preparation unit is configured to connect to the fourth input of the decision block only after the completion of the formation of the map of the re-reflections zones, and the third input of the space-time processing unit is configured to be connected to the first output of the closing angles archive; and the second input of the spatio-temporal processing unit is connected to the first output of the archive of altitude boundaries of visibility.

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