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MHT4010-2024: Technical specification of ATC secondary surveillance radar
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Technical specification of ATC secondary surveillance radar
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(Technical specification for air surveillance secondary surveillance radar system)
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PDF similar to MHT4010-2024
Standard similar to MHT4010-2024 JT/T 808 JT/T 1078 GB/T 19392 MH/T 4027 Basic data | Standard ID | MH/T 4010-2024 (MH/T4010-2024) | | Description (Translated English) | Technical specification of ATC secondary surveillance radar | | Sector / Industry | Civil Aviation Industry Standard (Recommended) | | Classification of Chinese Standard | M53 | | Classification of International Standard | 49.090 | | Word Count Estimation | 31,357 | | Date of Issue | 2024-02-27 | | Date of Implementation | 2024-03-01 | | Older Standard (superseded by this standard) | MH/T 4010-2016 | | Issuing agency(ies) | Civil Aviation Administration of China | MHT4010-2016: (Technical specification for air surveillance secondary surveillance radar system)
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Technical standards for ATC secondary surveillance radar
ICS 49.090
M 53
MH
Civil Aviation Industry Standard of the People's Republic of China
Replace MH/T 4010-2006
Technical specification of secondary surveillance radar system for air traffic control
2016-10-09 released
2017-01-01 implementation
Issued by Civil Aviation Administration of China
Table of contents
Foreword...II
1 Scope...1
2 Normative references...1
3 Terms, definitions and abbreviations...1
3.1 Terms and definitions...1
3.2 Abbreviations...4
4 Technical requirements...5
4.1 Composition...5
4.2 Classification...5
4.3 General requirements...5
4.4 Performance requirements...6
4.5 Query response mode...7
4.6 Antenna System...16
4.7 Interrogator...18
4.8 Track Recorder...20
4.9 Track processor...21
4.10 Monitoring and Maintenance System...21
4.11 Radar data output...22
4.12 Testing the answering machine...23
Appendix A (Normative Appendix) Mode C Coding...25
Appendix B (informative appendix) Schematic diagram of antenna vertical and horizontal directivity...51
Foreword
This standard was drafted in accordance with the rules given in GB/T 1.1-2009.
This standard replaces MH/T 4010-2006 "Technical Specification for Secondary Surveillance Radar Equipment for Air Traffic Control", and it is compatible with MH/T 4010-2006
Compared with the main technical changes as follows.
――Modified the standard name, and changed "equipment" to "system";
-Deleted the definition of the three-pulse interrogation system (2006 version 3.1.16);
- Added the definition of serious failure (see 3.1.21);
——Modified the system classification method (see 4.2,.2006 edition 4.2);
--- Increase the power requirements of the secondary surveillance radar system (see 4.3.5);
――The maximum range requirement of S mode is added (see 4.4.1);
-The target processing capability requirements of the secondary surveillance radar system have been revised (see 4.4.6,.2006 version 4.4.6);
――Requirements for receiver anti-jamming capability have been added (see 4.4.9d));
--Modified the definition of emergency code function (see 4.5.5.3,.2006 version 4.5.5.3);
――S-mode inquiry requirements have been added (see 4.5.7.2, 4.5.7.3);
---Added S mode airborne equipment characteristics requirements (see 4.5.10);
-Modified the meaning of the S-mode inquiry and response information fields (see 4.5.11,.2006 version 4.5.10);
-Modified the antenna azimuth pulse coding information (see 4.6.4,.2006 version 4.6.4);
--- Added antenna safety protection device requirements (see 4.6.6.6);
-Combine the chapters of "Monitor" and "Maintenance Display" into "Monitoring and Maintenance System" (see 4.10,.2006 editions 4.10, 4.11);
-Modified the data format requirements (see 4.11.1,.2006 version 4.12.1);
---Added the S-mode networking service interface requirements (see 4.11.2);
-Modified the data transmission protocol and rate requirements (see 4.11.3,.2006 version 4.12.2);
--Delete the data interface requirements (2006 version 4.12.6);
-Modified the clock interface requirements (see 4.11.7,.2006 version 4.12.7);
-Added the horizontal direction diagram (see Appendix B).
This standard was proposed and interpreted by the Air Traffic Control Industry Management Office of the Civil Aviation Administration of China.
This standard is under the jurisdiction of the China Academy of Civil Aviation Science and Technology.
Drafting organizations of this standard. Air Traffic Control Industry Management Office of Civil Aviation Administration of China, Second Research Institute of Civil Aviation Administration of China.
The main drafters of this standard. Guo Jing, Zhang Weixing, Ye Jiaquan, Fan Xiaomin, Pan Jie, Du Hui, Zhang Yong.
This standard was first published in July.2000 and revised for the first time in April.2006.
Technical specification of secondary surveillance radar system for air traffic control
1 Scope
This standard specifies the general technical requirements for secondary surveillance radar systems for civil aviation air traffic control.
This standard applies to conventional or monopulse secondary surveillance radar systems with A/C mode and S mode capabilities used by civil aviation
Design, development, construction and use of
2 Normative references
The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this article
Pieces. For undated references, the latest version (including all amendments) applies to this document.
3 Terms, definitions and abbreviations
3.1 Terms and definitions
The following terms and definitions apply to this document.
3.1.1
Secondary surveillance radar system
The radar system that locates the aircraft equipped with the airborne transponder through the inquiry of the ground interrogator and the response of the airborne transponder.
3.1.2
Interrogator
A system that transmits interrogation code pulses and receives response code pulses.
3.1.3
Aircraft address
For ground communication, navigation and surveillance purposes, a unique 24-bit binary code designated for each aircraft.
3.1.4
Range resolution
In the same azimuth, the ability of the radar to distinguish the smallest distance between adjacent aircraft.
3.1.5
Range curacy
Mean square error of radar range estimation.
3.1.6
Azimuth resolution
At the same distance, the ability of the radar to distinguish the smallest azimuth of adjacent aircraft.
3.1.7
Azimuth accuracy
The mean square error of the radar detection bearing estimation.
3.1.8
Discrimination
Complete the smallest resolvable unit given by the radar system for target coordinate measurement accuracy.
3.1.9
Asynchronous interference fruit
The secondary surveillance radar receives the interference caused by other secondary surveillance radar's query responses.
3.1.10
Framing pulses
Answer the two pulses with an interval of 20.3 μs in the code group.
3.1.11
Interleave reply
Response pulse groups overlap each other, but the pulse positions do not occupy each other response. See Figure 1.
Figure 1 Schematic diagram of interleaving code
3.1.12
Sync crosstalk garble
Response pulse groups overlap each other, and the pulse positions occupy each other response. See Figure 2.
Figure 2 Schematic diagram of synchronous crosstalk
3.1.13
Fake framework target phantom
The target formed by the wrong judgment frame pulse. See Figure 3 and Figure 4.
Figure 3 C2-SPI causes false frame targets
Figure 4 The response is close to causing false frame targets
3.1.14
Reflection false target ghost
False targets caused by reflections from obstacles.
3.1.15
Null depth
The ratio of the peak power of the difference () beam of the horizontal beam of a monopulse radar antenna to the minimum power of the difference () beam (center).
3.1.16
Tangent sensitivity
By observing the video output of the receiver on the oscilloscope, a pulse signal is used to increase the amplitude of the observed noise.
The input signal strength at the same height as the pulse itself. See Figure 5.
Figure 5 Schematic diagram of tangent sensitivity video waveform
3.1.17 Pulse parameter definition
3.1.17.1
Pulse amplitude
The peak voltage amplitude of the pulse envelope. See Figure 6.
Figure 6 Pulse waveform parameters
3.1.17.2
Pulse duration
The time interval between the rising and falling half-amplitude points (0.5A) of the pulse envelope. See Figure 6.
3.1.17.3
Pulse rise time
The time between the pulse envelope rising from 0.1A to 0.9A. See Figure 6.
3.1.17.4
Pulse decay time
The time between the pulse envelope falling from 0.9A to 0.1A. See Figure 6.
3.1.17.5
Pulse interval
The time interval between the half-amplitude (0.5A) point of the first pulse rising edge and the half-amplitude point of the second pulse rising edge. See Figure 6.
3.1.18
Conventional secondary surveillance radar
A secondary surveillance radar that uses ordinary pulse radar positioning technology to measure the space coordinates of a transponder-equipped aircraft.
3.1.19
Mono-pulse secondary surveillance radar
A secondary surveillance radar that uses monopulse radar angle measurement technology to measure the space coordinates of a transponder-equipped aircraft.
3.1.20
Critical failures
Failure or combination of failures that make the product unable to complete the specified tasks or may cause significant loss of people or material.
3.2 Abbreviations
The following abbreviations apply to this document.
4 Technical requirements
4.1 Composition
The secondary surveillance radar system consists of an antenna, a turntable (rotary joints, motors, code discs, etc.) and a feeder system, an interrogator, a track recorder and
It consists of track processor, monitoring and maintenance system and test transponder.
4.2 Classification
Secondary radar surveillance systems are generally divided into conventional secondary surveillance radar systems and monopulse secondary surveillance radar systems from the perspective of target positioning technology;
From the query response capability, it is divided into the secondary surveillance radar system and the S mode secondary surveillance radar system.
4.3 General requirements
4.3.1 The secondary surveillance radar system should meet the requirements of Volume IV of Annex 10 "Aeronautical Telecommunications" of ICAO "Convention on International Civil Aviation".
4.3.2 The composition of the secondary surveillance radar system (except the antenna feeder system and the maintenance display) should adopt a dual-machine configuration and should be able to switch automatically. Assume
The equipment should be able to work continuously for 24 hours.
4.3.3 The equipment composed of the secondary surveillance radar system shall adopt all solid-state semiconductor devices, and shall have corresponding normal and fault monitoring instructions.
4.3.4 Under the condition of single channel equipment configuration of secondary surveillance radar system, the MTBF of the system should be greater than 1 500 h; conditions of dual channel configuration
Under the conditions, MTBCF should be greater than 20 000 h. The MTTR of the indoor equipment of the secondary surveillance radar system should be less than 0.5 h, and the MTTR of the outdoor equipment should be less than 0.5 h.
In 2 h.
4.3.5 The power supply of the secondary surveillance radar system should have overcurrent and overvoltage protection capabilities. The working power supply supports 220 V±22 V, 380 V±38 V,
The frequency is 45 Hz～63 Hz.
4.3.6 The environmental requirements of the secondary surveillance radar system are as follows.
4.4 Performance requirements
4.4.1 Maximum range
The maximum range of the conventional secondary surveillance radar should not be less than.200 n mile; the maximum range of the monopulse secondary surveillance radar should not
Less than 250 n mile; the maximum range of the S mode secondary surveillance radar should not be less than.200 n mile, and the coverage limit should not be less than
20 116.8 m (66 000 ft).
4.4.2 Minimum range
In all azimuths, when the vertical antenna beam elevation angle is between 0.5° and 50°, the minimum range should not exceed 0.5 n mile.
4.4.3 Distance parameters
The range resolution should not be greater than 75 m, and the ranging accuracy should not be greater than 29 m (not including the ranging error introduced by the response delay of the transponder),
The distance discrimination should not be greater than 18 m.
4.4.4 Bearing parameters
The azimuth resolution of the monopulse secondary surveillance radar should not be greater than 0.6° (the condition is that A mode and C mode alternate), and the azimuth accuracy should not be greater than
0.05°, the azimuth angle discrimination should not be greater than 0.022°.
4.4.5 System response decoding effectiveness
The effectiveness of the A-mode code should be greater than 98%; the effectiveness of the C-mode code should be greater than 97%; the effectiveness of the S-mode code should be greater than 99%.
4.4.6 Target processing capability
When the speed is not less than 10 r/min, the target processing capacity should meet the requirements of Table 1.
4.4.8 Anti-interference ability
The system should have the following anti-interference capabilities.
a) Ability to suppress asynchronous interference from the sidelobe of the interrogating antenna from any direction. In the worst asynchronous interference (10,000 times per second)
Under the condition of, the target report should not be lost, and there should be no more than one false target report per scan (360º);
b) Ability to suppress false targets reflected in the main lobe of the interrogation antenna;
c) Ability to suppress false framework targets;
d) The receiver should be able to handle continuous wave (amplitude -95 dBm～-20 dBm) and pulse continuous wave interference (two overlapping pulse sequences,
The first -40 dBm, the second -60 dBm overlap the first 0.7 μs).
4.5 Query response mode
4.5.1 A/C mode query
4.5.1.1 The A/C mode query coding adopts a three-pulse system (see Figure 5). The interval between pulses P1 and P2 should be 2.00 μs ± 0.15 μs.
4.5.1.2 A/C mode query coded pulses P1, P2 and P3 should meet the following requirements.
a) The stroke width is 0.8 μs±0.1 μs;
b) The pulse rise time is 0.05 μs～0.1 μs;
c) The pulse fall time is 0.05 μs～0.2 μs.
4.5.1.3 A/C mode query mode is shown in Table 2.
Table 2 Inquiry mode
Interrogation mode P1 and P3 pulse interval function
A mode 8.0 μs±0.2 μs air traffic control identification query
C mode 21.0 μs±0.2 μs height query
4.5.1.4 The interrogator should have the characteristics of interrogating sidelobe suppression. P1 and P3 pulses are radiated by directional (and) beams, and P2 pulses are suppressed by sidelobes.
(Control) beam radiation.
4.5.1.5 Within the range required by the inquiry, the radiation intensity of P2 should be 9 dB lower than the radiation intensity of P1;
Because of the intensity of radiation P1 from the side lobe of the interrogation antenna.
4.5.1.6 Within the beam width (main lobe) required by the directional antenna, the radiation intensity of P3 should be within ±l dB of the radiation intensity of P1.
4.5.2 Joint mode query
4.5.2.1 In the joint mode query, the P4 pulse should be added at 2.0 μs after the P3 pulse (see Figure 7). When the P4 pulse width is 0.8 μs,
It is A/C mode full call inquiry; when the P4 pulse width is 1.6 μs, it is A/C/S mode full call inquiry.
4.5.2.2 When the answering machine receives a valid A/C mode full call inquiry, the answering machine with A/C mode function should generate the corresponding mode
The answering signal of the S-mode capable transponder does not respond.
4.5.2.3 When the answering machine receives a valid A/C/S mode full call inquiry, the A/C mode answering machine and the answering machine with S mode capability
The machine should generate the response signal of the corresponding mode.
Figure 7 Joint inquiry mode
4.5.3 S mode query
4.5.3.1 The S mode interrogation signal adopts the signal form shown in Figure 8.The width of the P6 pulse is 16.25 μs or 30.25 μs, including
56 or 112 bits of interrogation information, P5 pulses are transmitted through the control channel for interrogation of side lobe suppression.
4.5.3.2 When an answering machine with S mode capability receives a valid S mode full call inquiry, it shall generate a corresponding S mode full call response.
4.5.3.3 When the interrogator sends an interrogation message to all Mode S transponders, the transponder does not need to respond.
4.5.3.4 When an answering machine with S-mode capability receives a valid S-mode selective inquiry, only when the address of the answering machine and the inquiry signal are
When the addresses included are the same, the corresponding S mode response is generated.
4.5.3.5 The characteristics of the query pulse are shown in Table 3.
4.5.4 A/C mode response code (see Figure 9)
4.5.4.1 Frame pulse
The response should use a signal composed of two pulses separated by 20.3 μs as the most basic code. These two pulses are defined as frame pulses,
Marked as F1 and F2.
4.5.4.2 Information pulse
The information pulse shall be composed in increments of 1.45 μs after the first frame pulse. The signs and positions of these pulses should conform to Table 4
Provisions.
4.5.4.3 SPI pulse
The SPI pulse should be manually selected and transmitted by the pilot. When needed, the pulse should be transmitted in the A mode response, and its position is in the last box
After the frame pulse is 4.35 μs, the pulse width is 0.45 μs.
4.5.4.4 Tolerance of response pulse position
The tolerance between each pulse of response and the first frame pulse shall be ±0.1 μs. SPI pulse and the last frame pulse in the response group
The tolerance of shock shall be ±0.1 μs. The interval between any pulse in the response group and other pulses in the response group (except the first frame pulse)
The tolerance should not be greater than 0.15 μs.
4.5.4.5 Response pulse characteristics
All response coded pulse parameters should meet the following requirements.
4.5.5 A mode response code
4.5.5.1 The response code for mode A inquiry is the identification code, which should be composed of the two frame pulses specified in 4.5.4.1 and the information pulse specified in 4.5.4.2
Punch composition. The information pulse is selected according to the coding needs.
4.5.5.2 A mode response code should be able to manually select 4096 kinds.
4.5.5.3 The 7700, 7600, and 7500 in the A mode response code are emergency codes. Table 5 shows the role of emergency codes.
4.5.5.4 The A mode code is composed of Arabic numerals 0～7, and should be the sum of the subscripts of the same letter pulse specified in 4.5.4.A mode should
The order of answer codes is shown in Table 6.
4.5.6 C mode response code
4.5.6.1 The response code of C mode inquiry is height code. When the digitized air pressure altitude information is valid, the response code of the C mode query should be changed by
It is composed of two frame pulses and information pulses specified in 4.5.4.1 and 4.5.4.2.The position of the information pulse should meet Appendix A according to the barometric altitude
Requirements.
4.5.6.2 C mode response code should be composed of standard cyclic code (Gray code) and five-period cyclic code, see Table 7.
The letter D1 of the standard cyclic code is not used (always 0), D2 represents the most significant bit (MSB), and the increment of the standard cyclic code is about 150 m (500 ft).
The letter C4 of the five-cycle cyclic code represents the lowest bit (LSB), and the increment of the five-cycle cyclic code is about 30 m (100 ft). Five-period cyclic code encoding
The rules are shown in Table 8.
4.5.7 Uplink query format in S mode
4.5.7.1 There are 25 uplink query formats in S mode, as shown in Figure 10.
Note 2.N represents an unallocated N-bit code, these bits are "0" when sending.
Note 3.Upstream format (UF) 0 to 23 correspond to the first five digits of the interrogation signal. When UF=24, it is only defined by the first two positions "11" of the interrogation signal, and the other three digits
It is determined by the content of the interrogation signal.
Figure 10 Uplink query format in S mode
4.5.7.2 The inquiry frequency of S mode is 1 030 MH z ± 0.01 MH z.
4.5.7.3 The mode S query carrier is pulse modulation, and the data pulse (P6) should adopt phase modulation and meet the following requirements.
a) Pulse modulation. Both joint query and S mode query are composed of pulse sequences. The pulse that forms a specific interrogation pattern can be expressed as
P1, P2, P3, P4, P5 and P6 pulses (P1, P2, P3, P4, P5 and P6 pulses can be used to form specific interrogation modes);
b) Phase modulation. P6 pulse has two forms. long (30.25 μs) and short (16.25 μs), and its internal uses a binary difference of 4 Mbps
Split phase shift modulation, that is, phase modulation (of the carrier) is achieved by 180º phase reversal;
c) Phase reversal duration. the duration of the interrogation (phase) reversal is less than 0.08 μs, the phase monotonically increases (or decreases), and the phase
There must be no amplitude modulation during bit conversion.
4.5.8 S mode response code (see Figure 11)
4.5.8.1 The response frequency of S mode is 1 090 MH z±1 MH z.
4.5.8.2 The S mode response consists of four leading pulses and 56 or 112-bit response data blocks. The response data adopts binary pulse position adjustment.
When the pulse appears in the first half, it represents "1", and when it appears in the second half, it represents "0".
4.5.8.3 The interval between the first leading pulse of the S mode response and the following three leading pulses is 1 μs, 3.5 μs and 4.5 μs respectively.
4.5.8.4 The amplitude change of any two pulses in the S mode response should not exceed 2 dB.
4.5.8.5 S mode response pulse characteristics are shown in Table 9.
Figure 11 S mode response coding format
4.5.9 S mode downlink response format
4.6.3 Polarization form
The polarization mode should be vertical polarization.
4.6.4 Field characteristics of interrogation beam
4.6.4.1 Horizontal pattern
4.6.4.1.1 Antenna gain
The gain of the secondary radar antenna should meet the requirements of the maximum range.
The monopulse secondary radar antenna shall meet the following requirements.
a) The maximum gain of the main lobe of the sum (∑) beam is not less than 27 dB;
b) The sidelobe gain of the sum (∑) beam is less than the main lobe gain by 27 dB;
c) The tail lobe gain of the sum (∑) beam is 30 dB less than the main lobe gain.
4.6.4.1.2 Beam width
The beam width of the secondary radar antenna should meet the requirements of response signal detection and decoding processing.
When using single pulse system.
a) The 3 dB beam width should be 2.45°±0.25°;
b) The 10 dB beam width should not be greater than 4.5°;
c) The 20 dB beam width should not be greater than 7°.
4.6.4.1.3 Zero depth
Using monopulse antenna system, the zero depth of the difference (△) beam should be greater than 30 dB.
4.6.4.1.4 Crossover level
The monopulse antenna system is adopted, and the cross level of the sum (∑) beam and the difference (△) beam in the main lobe should be lower than the sum (∑) beam
The peak level is 2 dB～3 dB. The difference between the two crossover levels should be less than 0.5 dB.
4.6.4.2 Vertical directional graph
4.6.4.2.1 The gain of the vertical beam on the antenna axis shall meet the requirements of the maximum operating distance.
4.6.4.2.2 When a large vertical aperture array antenna is used, the vertical beam of the antenna shall have the characteristics of modified cosecant square and sharp cut-off at the bottom. in
In the range of 6 dB～16 dB below the maximum value of the vertical directivity pattern, the sharp cut-off rate should be greater than 1.8 dB per degree. See Appendix B.
4.6.4.2.3 Below the horizontal plane 6°, the gain of the vertical directivity pattern should be less than the maximum value of 18 dB. See Appendix B.
4.6.4.2.4 At 50° above the horizontal plane, the gain of the vertical directivity pattern should not be less than 7 dB. See Appendix B.
4.6.5 Field characteristics of the control beam
4.6.5.1 Within the angle required for interrogation, the gain of the control beam should be 9 dB lower than the gain of the interrogation beam.
4.6.5.2 In addition to the angle required for interrogation, the gain of the control beam should not be less than the gain of the sidelobe of the interrogation beam (Σ).
4.6.5.3 The horizontal beam shall meet the requirements of 4.6.5.1 when the elevation angle of the antenna vertical beam is 0°～50°.
4.6.6 Antenna base
4.6.6.1 The antenna speed is 6 r/min～15 r/min, optional.
4.6.6.2 The antenna should be capable of pitch adjustment from -2° to +7°.
4.6.6.3 The antenna system should output north information and azimuth pulse code information to the recorder.
4.6.6.4 The position pulse coding information is 14 bits.
4.6.6.5 When the primary radar antenna and the secondary radar antenna are combined, the misalignment caused by the installation error will be
The pitch angle should be less than ±0.2°.
4.6.6.6 The antenna safety protection device shall meet the following requirements.
--With a safety circuit, the antenna drive will be automatically turned off under abnormal working conditions;
--With safety linkage device, turn off the antenna drive and stop radiation when the antenna needs to be shut down;
--With a locking mechanism to prevent the antenna from rotating during maintenance.
4.6.6.7 The antenna body (including outdoor equipment) should work normally under the following en...
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