CN111913176B

CN111913176B - Method for independently realizing target IFF identification by secondary radar

Info

Publication number: CN111913176B
Application number: CN202010747218.9A
Authority: CN
Inventors: 王亚涛; 王谊; 黄晓卿; 潘向荣; 兰鹏
Original assignee: Southwest Electronic Technology Institute No 10 Institute of Cetc
Current assignee: Southwest Electronic Technology Institute No 10 Institute of Cetc
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2023-07-21
Anticipated expiration: 2040-07-30
Also published as: CN111913176A

Abstract

The invention provides a method for independently realizing target IFF identification by a secondary radar, and aims to provide a method which is independent of primary radar guiding and can quickly, accurately and reliably identify a target. The invention is realized by the following technical scheme: the secondary radar integrated interrogator system alternately scans in a fixed repeated sequence SSR interrogation working mode, the interrogator receives and decodes the aircraft response signal, sends target track data into a radar display control terminal, and selects a target to be subjected to IFF identification; judging whether the current direction has a friend-foe-identification IFF target or not when the secondary radar scanning inquiry works; sending out IFF queries for a plurality of times according to a mode appointed by the display control terminal, receiving IFF response, and switching back to an A/C mode SSR autonomous query; and the radar display control terminal matches the identification result with the secondary radar track, fuses the identification information into the target track label and the list, updates the track label and the list, and completes the IFF identification process.

Description

Method for independently realizing target IFF identification by secondary radar

Technical Field

The invention relates to a method suitable for independently realizing western system target IFF identification by a secondary radar. The secondary radar expansion application technology belongs to a western system friend and foe identification system, and particularly relates to an identification method for autonomous-to-air monitoring capability by utilizing a secondary radar.

Background

The Western system friend-foe identification IFF system friend-foe identification device is evolved from the initial basic mode M1/2/3/C to the current encryption mode M4/5. The encryption mode M5 is a newly added mode of the active friend-foe identification system MarkXIIA, has the encryption protection of a modern encryption computer, is not easy to decipher or forge, can be applied to air-to-air, air-to-sea, ground-to-air and other environments, and has a certain research value. The method comprises the steps that a friend-foe identifier uses the working principle of a secondary radar, adopts an inquiry-response working mode to judge and identify the friend-foe attribute of a target through inquiry-response communication, completes attribute identification and information acquisition of the target, namely an inquiry signal is sent by an inquiry machine, the response machine sends a response code of the responder after receiving the inquiry signal, and the identification of a responder platform can be completed after the inquiry machine decodes the response signal. Since friend or foe Identification (IFF) is an automatic target identification technique, it can be inundated with large amounts of data in the ocean, leading to catastrophic results. It is important to quickly, accurately and reliably identify the target. The secondary radar used for civil aviation monitoring can be independently scanned, an inquiry signal is automatically sent according to a certain repetition frequency, the inquiry mode is A, C, S for civil use, and the like, and a track of an aircraft target in a monitored air space can be formed according to a response result. The conventional western system friend or foe identifier for military use needs to initiate inquiry of a designated target under the guidance of a primary radar, the primary radar needs to start a transmitter to work and transmit target echo information to a radar display console, the radar display console provides primary radar track display of the target in an airspace, the inquiry of the designated target needs to be initiated under the guidance of the primary radar, namely the primary radar provides information such as lot number, azimuth, distance and the like of the target, and when the friend or foe identification inquiry is initiated on a certain selected target, the radar display console provides information such as lot number, azimuth, distance, identification mode and the like of the target, and the identification mode is 1, 2, 3, 4, 5 and the like of military. And then returning the response result to the radar once, and fusing the identification information and the radar information once by the radar once to finish the judgment of the attribute of the target friend or foe. After the inquiry machine is identified by the friend or foe, the response result is returned to the radar display console once, and the identification information and the radar information are fused by the radar display console once, so that the identification of the target friend or foe attribute is completed. However, the friend or foe identifier has a plurality of defects: such as wind and rain, sand storm, and smoke from nitric acid; under the environment of rapid change of situation, it is difficult to distinguish the targets of canine tooth interleaving and mutual approximation; especially at night, it is difficult to cope with the scene where various vehicles are mixed together. The traditional identifier (including air traffic control) adopts a one-to-one answer mode and is in a full call mode, after the inquiry equipment sends out an inquiry, the inquiry equipment waits for receiving a response signal and processing the response signal to carry out second inquiry, the time occupied by one inquiry is longer, and the inquiry identification efficiency is lower. The device is easy to be deceptively answered, so that the time of answering the device is occupied, and the inquiry of the user cannot timely receive the answer information and is misjudged.

At present, a part of more complex friend-foe identification systems have the function of a secondary radar at the same time, but the two functions of the secondary radar and the friend-foe identification cannot be operated at the same time. The traditional secondary surveillance radar comprises a mode A, C, and due to the problem of self-body system, the target resolution is poor, synchronous crosstalk and asynchronous crosstalk (friit) are easy to occur, and the number (a) of codes used in the mode A cannot meet the requirements of navigation management. The asynchronous crosstalk can only be restrained by a plurality of interrogation at present, but the influence on the identifier cannot be completely eliminated. Multipath reflections occur when electromagnetic waves emitted by an interrogator or transponder encounter peaks or tall buildings. Interrogation signals are prone to spurious targets when they encounter reflections. Reflection of the reply signal affects decoding of the interrogation device and thus the determination of the target by the identifier. The poor target resolution greatly reduces the resolution of the recognizer targets due to synchronous crosstalk, asynchronous crosstalk and multipath emission, and in addition, the beams are wider due to the limitation of the platform on the antenna size, so that multiple targets are easy to appear in the beams. The presence of multiple targets also reduces their recognition probability. When the secondary radar independently scans, a friend or foe identification inquiry cannot be initiated on the target, the working mode must be switched to a friend or foe identification state, the primary radar provides target guiding information, and the friend or foe identification on the target can be completed. Because the primary radar transmitter is a high-power easy-to-wear part, the primary radar transmitter is started to work in a short time in general, which brings inconvenience to the identification task of the enemy.

Disclosure of Invention

The invention aims to provide a method for realizing the IFF identification of a target in a western system by a secondary radar which can quickly, accurately and reliably identify the target without depending on the guiding of the primary radar aiming at the defects existing in the prior art.

The above object of the present invention is achieved by the following technical scheme: the method for independently realizing target IFF identification by using the secondary radar is characterized by comprising the following steps of: based on a western system friend-foe identification and secondary radar integrated interrogator system, performing alternating autonomous scanning work of a navigation management A/C mode in a fixed repeated sequence SSR working mode, scanning and inquiring an antenna 360-degree real-time angle, receiving and decoding an aircraft response signal, ranging and measuring angles, and sending formed target track data into a radar display control terminal for secondary radar track display; then, an operator selects an IFF target for identification of the friend or foe on the radar display control terminal, selects a target to be identified by the IFF, selects an IFF inquiry mode, inquires and starts, and the radar display control terminal transmits information such as a target batch number, the azimuth, the distance and the like of the target to the IFF/SSR integrated inquiry machine through a network interface or a serial port to store the information of the IFF target; when the secondary radar scanning inquiry works, working time sequences of the inquiry works are arranged, a friend-foe identification work task is inserted into the automatic scanning inquiry flow, and whether the current direction has a friend-foe identification IFF target is judged; when an inquiring antenna scans the direction of an inquired target, the IFF/SSR integrated inquiring machine temporarily interrupts the A/C mode autonomous inquiring, pauses the fixed repeated sequence SSR inquiring, sends out a plurality of times of friend-foe identification IFF inquiring according to the mode appointed by the radar display control terminal, receives an IFF response, processes the result, and then switches back to the A/C mode autonomous inquiring; the IFF inquires the identification result and the target lot number and returns the radar display control terminal through a network interface or a serial port; and the radar display control terminal matches the identification result with the secondary radar track according to the target lot number, fuses the identification information into the target track label and the list, updates the track label and the list, and completes the identification flow of the I/F.

Compared with the prior art, the invention has the following beneficial effects.

According to the invention, based on a western system of the integrated interrogator system for the friend and foe identification and the secondary radar, when the secondary radar scans and inquires, the working time sequence of the interrogator is reasonably arranged, the friend and foe identification work task is inserted into the automatic scanning and inquiring process, the scanning and inquiring efficiency is not influenced, the capability of independently carrying out the friend and foe identification by the IFF interrogator with the secondary radar function is realized through the design of the working process of the interrogator, the primary radar is not required to be relied on for guiding, and the friend and foe identification of the target is completed on the premise of not depending on the primary radar guiding.

Based on a western system friend-foe identification and secondary radar integrated interrogator system, the invention performs alternating autonomous scanning work of the navigation management A/C mode in an SSR working mode, scans and inquires an antenna 360 DEG in real time, receives and decodes an airplane response signal, measures distance and measures angle, and enables the friend-foe identifier to independently complete friend-foe identification of a target under the condition that primary radar does not emit. The radar display terminal independently displays the secondary radar track, and can select a target required to be subjected to IFF inquiry by an operator, and can also select an IFF inquiry mode.

The identification target is quick, accurate and reliable. When the secondary radar scanning inquiry works, working time sequences of the inquirers are arranged, a friend-foe identification work task is inserted into the automatic scanning inquiry flow, whether the current direction has an IFF target or not is judged, the identification result is judged, and then the automatic inquiry is switched back to the A/C mode; and the radar display control terminal matches the identification result with the secondary radar track according to the target lot number, fuses the identification information into the target track label and the list, and updates the track label and the list. The target can be identified quickly, accurately and reliably.

The invention is different from the conventional western system identification implementation mode in that: the conventional western system friend-foe identifier needs to initiate inquiry of a designated target under the guidance of a primary radar, the primary radar needs to start a transmitter to work and transmit target echo information to a radar display console, the radar display console provides primary radar track display of the target in a airspace, when a friend-foe identification inquiry needs to be initiated on a selected target, the radar display console provides information such as lot number, azimuth, distance, identification mode and the like of the target, the identification mode is 1, 2, 3, 4, 5 and the like of military, the inquiry machine returns a response result to the primary radar display console after the friend-foe identification inquiry, and the secondary radar display console fuses the identification information with the radar information to finish the judgment of the attribute of the target friend-foe. The radar display console does not need to enter a working state once, only needs to start up to work, the IFF interrogator autonomously scans to provide secondary radar track data, the radar display console displays a secondary track, when a certain selected target needs to initiate a friend-foe identification inquiry, the radar display console provides information such as batch numbers, azimuth, distance, identification modes and the like of the target from the secondary track, the identification modes are 1, 2, 3, 4, 5 and the like of military, the interrogator returns a response result to the primary radar display console after the friend-foe identification inquiry, and the radar display console fuses the identification information with the secondary track information to finish the judgment of the friend-foe attribute of the target.

The method is suitable for independently realizing the western system target IFF identification by the secondary radar.

Drawings

The invention will be further described with reference to the accompanying drawings and examples.

FIG. 1 is a flowchart of the operation of the secondary radar of the present invention to independently implement target IFF identification.

FIG. 2 is a schematic diagram of IFF interrogation timing and secondary radar interrogation timing.

Fig. 3 is an IFF inquiry start timing determination diagram.

Detailed Description

See fig. 1 and 2. According to the invention, based on a western system friend-foe identification and secondary radar integrated interrogator system, alternating autonomous scanning work of a navigation management A/C mode is carried out in a fixed repeated sequence SSR working mode, an antenna scans and inquires in 360-degree real-time angle, an aircraft response signal is received and decoded, and the distance and angle measurement are carried out, and formed target track data is sent to a radar display control terminal for secondary radar track display; then, an operator selects a target of the I/F identification on the radar display control terminal, selects a target to be identified by the I/F identification, selects an I/F inquiry mode, inquires and starts, and the radar display control terminal transmits information such as a target batch number, the azimuth, the distance and the like of the target to the I/F/SSR integrated inquiry machine through a network interface or a serial port to store the target information; when the secondary radar scanning inquiry works, working time sequences of the inquiry works are arranged, a friend-foe identification work task is inserted into the automatic scanning inquiry flow, and whether the current direction has a friend-foe identification IFF target is judged; when an inquiring antenna scans the direction of an inquired target, the IFF/SSR integrated inquiring machine temporarily interrupts the A/C mode autonomous inquiring, pauses the fixed repeated sequence SSR inquiring, sends out IFF inquiring for a plurality of times according to the mode appointed by the radar display control terminal, receives IFF response and processes the result, and then switches back to the A/C mode autonomous inquiring; the identification result of the friend-foe identification IFF inquiry and the target lot number are returned to the radar display control terminal through a network interface or a serial port; and the radar display control terminal matches the identification result with the secondary radar track according to the target lot number, fuses the identification information into the target track label and the list, updates the track label and the list, and completes the identification flow of the I/F.

The specific working flow is as follows:

1) The western system IFF/SSR integrated interrogator performs autonomous scanning operation in a navigation management A/C mode by adopting an SSR working mode, and an antenna scans and inquires 360 degrees, so that an A/C mode secondary radar track of an aircraft in a airspace is independently formed under the condition that the radar does not emit; then, an operator selects a target to be subjected to IFF identification on the radar display control terminal, and selects an IFF inquiry mode, and the radar display control terminal transmits information such as a target batch number, the azimuth, the distance and the like of the target to the IFF/SSR integrated inquiry machine through a network interface or a serial port; the IFF/SSR integrated interrogator briefly interrupts the A/C mode autonomous interrogation when an interrogation antenna scans the direction of an interrogated target, sends out a plurality of times of friend-foe identification IFF interrogation according to the mode appointed by the radar display control terminal, judges the identification result, and then switches back to the A/C mode autonomous interrogation; the IFF/SSR integrated inquiry machine sends back a radar display control terminal through a network interface or a serial port according to the identification result of the I/F inquiry and the target lot number; and the radar display control terminal matches the identification result with the secondary radar track according to the target lot number, and fuses the identification information into the target track label and the list to complete the identification flow of the I/F.

2) The operator selects the target which needs to be inquired by the IFF, selects the inquiry mode of the IFF which is identified by the friend or foe, and after the inquiry target is selected, the radar display terminal needs to extract the radar lot number, the latest distance and the latest position of the target to be inquired from the target real-time list, and the radar lot number, the latest distance and the latest position are transmitted to the IFF inquiry machine together with the inquiry mode through a network interface or a serial port.

3) After receiving the target information to be identified sent by the radar display terminal, the IFF interrogator stores the target information to be identified into a target list to be interrogated, and the target information is arranged in sequence according to the angle sequence. The IFF interrogator monitors the direction of the antenna axis in real time while performing SSR scanning interrogation, and when a target enters the antenna interrogation beam, the fixed repeated sequence SSR working mode is switched to the I/O identification IFF working mode.

4) After the target enters the antenna interrogation beam, suspending SSR scanning interrogation, inserting at least 4 times of friend-foe identification IFF interrogation, and processing 4 interrogation results, wherein if two or more interrogation results are successful, the target is identified as the target, otherwise, the target is identified as an unknown target.

5) The IFF interrogator sends the identification result to the radar display control terminal through the network port or the serial port, and immediately restores the SSR scanning interrogation mode of the fixed repeated sequence, and continues to carry out SSR scanning interrogation of the fixed repeated sequence.

6) After the radar display control terminal receives the target identification result, the identification result is matched with the secondary radar track according to the target lot number, identification information is fused into a target track label and a list, and the targets identified as the targets are distinguished in color in a target display interface, so that an IFF identification process is completed.

See fig. 2. The detailed manner of identifying IFF query timing and fixed repeat sequence SSR query timing by friend is: 1) The IFF interrogator sets the repeat frequency to 200-250 queries per second in the initial state, each query interval is 1-4 ms, autonomous scanning query is carried out according to the SSR working state that the antenna scanning speed is 5-10 turns per minute, the beam width is 1-3 degrees, and the residence time is 3/(360 x 10/60) =0.05s=50 ms, and 2-12 SSR queries are completed in one beam residence period, wherein 6-8 queries correspond to the target condensation point.

2) When an IFF inquiry needs to be carried out on a specific target, after the IFF inquiry machine judges that the target enters an inquiry beam through an antenna in real time, the IFF inquiry machine starts 4 times of IFF inquiries and then resumes SSR inquiries, 8 times of fixed repeated sequence SSR inquiries can be completed in a resident beam, the requirement of 6-8 times of spot condensation is met, and obvious influence on spot condensation corresponding to the target is avoided.

See fig. 3. The method for judging whether the target to be interrogated enters the interrogating antenna beam comprises the following steps: when the query antenna scans and rotates, the IFF query machine compares the real-time pointing angle of the antenna with the angle of the target, an angle encoder in the antenna turntable sends at least 4096 azimuth pulse information to the IFF query machine every 360 degrees, the rotation speed of the antenna is at least 60 degrees per second, the time interval of each azimuth pulse is less than or equal to 1/(4096/6) = 0.00146 s=1.46 ms, the antenna pointing is updated every 1-1.46 ms, whether the target enters the query antenna beam is judged, when the target to be queried enters the query beam range, the IFF query machine switches the query working mode into the IFF mode, and judges according to the antenna pointing gamma, the antenna beam width alpha and the target azimuth to be queried in real time, when the target angle beta=gamma+alpha/2, the target to be queried enters the query beam range, the IFF query machine switches the query working mode into the IFF mode, and 4 continuous queries adopt the IFF query.

While the foregoing is directed to the preferred embodiment of the present invention, it is noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. Various modifications and improvements may be made by those skilled in the art without departing from the spirit and substance of the invention, and are also considered to be within the scope of the invention.

Claims

1. The method for independently realizing target IFF identification by using the secondary radar is characterized by comprising the following steps of: based on a western system friend-foe identification and secondary radar integrated interrogator system, performing alternating autonomous scanning work of a navigation management A/C mode in a fixed repeated sequence SSR (simple sequence) interrogation work mode, scanning and inquiring an antenna 360-degree real-time angle, receiving and decoding an aircraft response signal, ranging and measuring angles, and sending formed target track data to a radar display control terminal for secondary radar track display; then, an operator selects an IFF target for identification of the friend or foe on the radar display control terminal, selects a target to be identified by the IFF, selects an IFF inquiry mode, and transmits the target batch number, the azimuth and distance information of the target to an IFF/SSR integrated inquiry machine through a network interface or a serial port for storing the IFF target information; when the secondary radar scanning inquiry works, working time sequences of the inquiry works are arranged, a friend-foe identification work task is inserted into the automatic scanning inquiry flow, and whether the current direction has a friend-foe identification IFF target is judged; when an inquiring antenna scans the direction of an inquired target, the IFF/SSR integrated inquiring machine temporarily interrupts the A/C mode autonomous inquiring, pauses the repeated sequence SSR inquiring, sends out a plurality of times of friend-foe identification IFF inquiring according to the mode appointed by the radar display control terminal, receives an IFF response, processes a result, and then switches back to the A/C mode SSR autonomous inquiring; the IFF inquires the identification result and the target lot number and returns the radar display control terminal through a network interface or a serial port; and the radar display control terminal matches the identification result with the secondary radar track according to the target lot number, fuses the identification information into the target track label and the list, updates the track label and the list, and completes the identification flow of the I/F.

2. The method for independently implementing target IFF identification by secondary radar as claimed in claim 1, wherein: the western system IFF/SSR integrated interrogator performs autonomous scanning operation in a navigation management A/C mode by adopting an SSR working mode, and an antenna scans and inquires 360 degrees, so that an A/C mode secondary radar track of an aircraft in a airspace is independently formed under the condition that the radar does not emit; then, an operator selects a target to be subjected to IFF identification on the radar display control terminal, and selects an IFF inquiry mode, and the radar display control terminal transmits the target batch number, the azimuth and distance information of the target to the IFF/SSR integrated inquiry machine through a network interface or a serial port.

3. The method for independently implementing target IFF identification by secondary radar as claimed in claim 2, wherein: the IFF/SSR integrated interrogator briefly interrupts the A/C mode autonomous interrogation when an interrogation antenna scans the direction of an interrogated target, sends out a plurality of friend-foe identification IFF interrogation according to the mode appointed by the radar display control terminal, judges the identification result, and then switches back to the A/C mode SSR autonomous interrogation; the IFF/SSR integrated inquiry machine sends back a radar display control terminal through a network interface or a serial port according to the identification result of the I/F inquiry and the target lot number; and the radar display control terminal matches the identification result with the secondary radar track according to the target lot number, and fuses the identification information into the target track label and the list to complete the identification flow of the I/F.

4. The method for independently implementing target IFF identification by secondary radar as claimed in claim 1, wherein: the operator selects the target which needs to be subjected to the IFF inquiry, selects the inquiry mode of the IFF which is identified by the friend or foe, and extracts the radar lot number, the latest distance and the latest direction of the target to be inquired from the target real-time list after selecting the inquired target, and the radar lot number, the latest distance and the latest direction of the target to be inquired are transmitted to the IFF inquiry machine together with the inquiry mode through a network interface or a serial port.

5. The method for independently implementing target IFF identification by secondary radar as claimed in claim 1, wherein: after receiving target information to be identified sent by a radar display terminal, the IFF interrogator stores the target information to be identified into a target list to be interrogated, and the target information to be identified is arranged in sequence according to an angle sequence; the IFF interrogator monitors the direction of the antenna axis in real time while performing SSR scanning interrogation, and when a target enters the antenna interrogation beam, the fixed repeated sequence SSR working mode is switched to the I/O identification IFF working mode.

6. The method for independently implementing target IFF identification by secondary radar as claimed in claim 1, wherein: after the target enters the antenna interrogation beam, suspending the SSR scanning interrogation of the fixed repeated sequence, inserting at least 4 times of identification IFF interrogation, and processing the 4 times of interrogation results, wherein if two or more interrogation results are successful, the target is identified as the target, otherwise, the target is identified as the unknown target.

7. The method for independently implementing target IFF identification by secondary radar as claimed in claim 1, wherein: the IFF interrogator sends the identification result to the radar display control terminal through the network port or the serial port, and immediately restores the SSR scanning interrogation mode of the fixed repeated sequence, and continues to carry out SSR scanning interrogation of the fixed repeated sequence.

8. The method for independently implementing target IFF identification by secondary radar as claimed in claim 1, wherein: after the radar display control terminal receives the target identification result, the identification result is matched with the secondary radar track according to the target lot number, identification information is fused into a target track label and a list, and the targets identified as the targets are distinguished in color in a target display interface, so that an IFF identification process is completed.

9. The method for independently implementing target IFF identification by secondary radar as claimed in claim 1, wherein: the IFF interrogator sets the repeat frequency to 200-250 queries per second in the initial state, each query interval is 1-4 ms, autonomous scanning query is carried out according to the SSR working state that the antenna scanning speed is 5-10 turns per minute, the beam width is 1-3 degrees, and the residence time is 3/(360 x 10/60) =0.05s=50 ms, and 2-12 SSR queries are completed in one beam residence period, wherein 6-8 queries correspond to the target condensation point.

10. The method for independently implementing target IFF identification by secondary radar as claimed in claim 1, wherein: when the query antenna scans and rotates, the IFF interrogator compares the real-time pointing angle of the antenna with the angle of the target, an angle encoder in the antenna turntable sends at least 4096 azimuth pulse information to the IFF interrogator every 360 degrees, the rotation speed of the antenna is at least 60 degrees per second, the time interval of each azimuth pulse is less than or equal to 1/(4096/6) = 0.00146 s=1.46 ms, the antenna pointing is updated every 1-1.46 ms, whether the target enters the query antenna beam is judged, when the target to be queried enters the query beam range, the IFF interrogator switches the query working mode into the IFF mode, and judges according to the antenna pointing gamma, the antenna beam width alpha and the target azimuth to be queried in real time, when the target angle beta=gamma+alpha/2, the target to be queried enters the query beam range, the IFF interrogator switches the query working mode into the IFF mode, and then the IFF query is continuously used for 4 times.