CN108226874A - Secondary radar digital video display methods - Google Patents
Secondary radar digital video display methods Download PDFInfo
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- CN108226874A CN108226874A CN201711474166.7A CN201711474166A CN108226874A CN 108226874 A CN108226874 A CN 108226874A CN 201711474166 A CN201711474166 A CN 201711474166A CN 108226874 A CN108226874 A CN 108226874A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/04—Display arrangements
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- Computer Networks & Wireless Communication (AREA)
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- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention discloses a kind of secondary radar digital video display methods, after decoding obtains symbol and the confidence information of response, the distance of the response, orientation, symbol, confidence level will be written in dual port RAM successively, this dual port RAM is shared for signal processing with data processing, is divided into the region of 2 equal sizes；Signal processing generates an interruption in each inquiry period starting, after data processing responds this interruption, the answer signal of last inquiry period acquisition is read from 1 region of dual port RAM, at the same time, another 1 region of dual port RAM is written in the answer signal currently generated by signal processing in real time, that is, ensures that 2 regions of dual port RAM are in the state of reading and write-in respectively.After data processing obtains answer signal, answer signal is shown into list by write-in digital video after the sequence rearrangement that orientation is ascending, same azran is near and far；And it is shipped regularly to display terminal.
Description
Technical field
Patent of the present invention is related to a kind of secondary radar digital video display methods, belongs to secondary radar target display technology,
Suitable for the display of monopulse secondary radar target response information, it is also applied for non-monopulse secondary radar target response information
Display.
Background technology
Secondary radar is the important information source of air control system, suitable for machine as air traffic control system important component
And Routing monitoring, it is possible to provide power coverage area is built-in have the distance of aircraft of airborne answering machine, orientation, pressure altitude,
Cognizance code and other distinctive marks are (such as：Critical, communication failure is held as a hostage etc.).
According to the operation principle of secondary radar, need airborne answering machine and secondary radar cooperating that could realize secondary thunder
Up to the function for monitoring to target.The wave beam that secondary radar is continuously rotated by 360 degree is to the airborne response in power coverage area
Machine sends out inquiry, airborne answering machine receive after the request signal of secondary radar according to interrogation mode difference make it is different should
It answers.Answer signal is by specific burst blocks into secondary radar obtains airborne answer by the identification and decoding to response train of pulse
The information such as position, pressure altitude, cognizance code and the distinctive mark code of machine are answered, so as to fulfill the monitoring to the cooperative target.It is logical
Often on radar target display terminal, with mark or flight path come display target for information about, and mark or flight path signal are sent
Toward the Control Centre of rear end, for airport monitoring or en route control.
Secondary radar often receives 1 response, the transponder pulse string arranged according to certain rules corresponding to 1, transponder pulse
It forms referring to Fig. 5.Transponder pulse is shown to the original video of referred to as secondary radar according to distance, orientation over the display.
To simplify the display of answer signal, the corresponding train of pulse of 1 response can also be represented with a pulse, the response letter shown in this way
It is known as digital video.According to the difference of secondary radar antenna rotating speed, the usual inswept target of a wave beam can obtain 8~15
Secondary response, corresponding raw video signal are 8~15 trains of pulse, and digital video signal is 8~15 pulses, put mark or boat
The relationship of 1 point of mark signal, signal form and equipment is referring to Fig. 1.The target information that digital video is shown is more former than point mark, flight path
Begin, in more detail, but simpler than original video.Generated during a target that wave beam is inswept the original videos of 11 responses, digital video,
The display example of point mark/flight path is referring to Fig. 2.The generation of digital video is related to antenna, feeder line, receiver, the letter of secondary radar
The all parts of the signals receiving paths such as number processing, data processing, display control, it is more smart in addition to that can show target information
Carefully, the judgement to secondary radar equipment state and fault location have highly important effect.
Different according to the method in test orientation, secondary radar is divided into two kinds of working systems of pulse and non-pulse, non-list
Pulse regime is traditional bearing measuring method, and operation principle is referring to Fig. 3, when target can be by entering wave beam relative to the orientation of radar
Beam position orientation with going out wave beam when beam position orientation be added after divided by 2 obtain.Non- system secondary radar monopulse because
Angle measurement accuracy is poor to be gradually eliminated.Monopulse secondary radar realizes Monopulse estimation skill using two Σ, Δ receiving channels
Art, operation principle is referring to Fig. 4, by receiving the calculating of signal amplitude to certain target Σ, Δ, obtains itself and poor ratio (Σ/Δ),
According to the correspondence with poor ratio and azimuth deviation amount, corresponding orientation correction value can obtain.In order to distinguish target in wave beam
The left side or the right of direction, monopulse systems introduce the concept of phase, and target is fallen on the azimuth axis left side, and Σ, Δ receive signal
Opposite in phase and poor ratio take negative value, and corresponding orientation correction value is negative angle；Target is fallen on the right of azimuth axis, and Σ, Δ connect
It receives the identical and poor ratio of signal phase and takes positive value, corresponding orientation correction value is positive-angle, is represented and poor ratio with 1 bit
It is positive and negative, and when target is fallen on azimuth axis or when close from azimuth axis, it is on a left side for azimuth axis that can not often tell target
Side or the right, at this time and poor ratio be defined as low confidence, also represented with 1 bit.
The original video of usual secondary radar shows that method is that secondary radar is being identified with dedicated display equipment
After transponder pulse, dedicated video display is given together by orientation, distance, apart from zero and transponder pulse string, video is shown
Device determines the relative position of transponder pulse on the screen by orientation, distance, apart from zero, real-time according to the pulse signal of input
Update display.Secondary radar original video contains much information, and renewal speed is fast, for real-time display raw video signal, needs special
Door is equipped with video display and video driver circuit.
With the development of electronic technology and the raising of integrated level, the processing capacity and arithmetic speed of computer are also carried
Rise, make it possible secondary radar video display with safeguarding that display terminal is combined into one, thus we by secondary radar answer
The original video for answering signal shows that being reduced to digital video shows, realizes on one computer while completes radar Working mould
Formula control, parameter setting, Stateful Inspection, the digital video of fault alarm and real-time display response target, point mark, flight path etc. are multiple
Function simplifies the peripheral equipment of secondary radar, improves radar operability and maintainability.
Invention content
To show secondary radar target information more more detailed than point/flight path, and to secondary radar equipment in radar terminal
Status monitoring and fault location provide effective foundation, while do not increase the hardware cost of secondary radar again, and the present invention proposes one
The novel secondary radar digital video display methods of kind, the method are suitable for pulse and non-monopulse secondary radar digital video
Display.
To solve problem above, present invention employs following technical solutions：A kind of secondary radar digital video display methods,
It is characterized in that after signal processing completes transponder pulse extraction, frame identification is carried out to pulse signal, only includes F1, F2 frame
The train of pulse of frame is just confirmed as a response, this response is represented with 1 pulse；F1 be train of pulse in the 1st pulse, F2
For last 1 pulse in train of pulse；
After decoding obtains symbol and the confidence information of response, by the distance of the response, orientation, symbol, confidence level successively
It is written in dual port RAM, this dual port RAM is shared for signal processing with data processing, is divided into the region of 2 equal sizes；At signal
Reason generates an interruption in each inquiry period starting, after data processing responds this interruption, is read from 1 region of dual port RAM
The answer signal that the last inquiry period obtains is taken, at the same time, write-in is double in real time by the answer signal currently generated for signal processing
Another 1 region of mouth RAM ensures that 2 regions of dual port RAM are in the state of reading and write-in respectively.Data processing obtains
After answer signal, be written after answer signal is resequenced by the sequence that orientation is ascending, same azran is near and far
Digital video shows list；And it is shipped regularly to display terminal.
The display terminal safeguards distance, orientation, symbol of the display terminal according to answer signal to safeguard display terminal
And confidence level, on display interface by predetermined color drawing response, there are pulses, show the digital video of secondary radar.
The present invention has following advantageous effect for the immediate prior art：It is shown using digital video, first
Frame Filtering is carried out to answer signal, the complete answer for only including F1, F2 frame pulse is just shown, has been filtered out due to more
The incomplete response that path, interference generate；Secondly symbol and confidence information are increased in digital video, is reflected with different colours
Position of the target in antenna beam, this is not exclusively advantageous for making standard to response signal quality, continuity, Orientation differences trend
Really judge, be more conducive to monitor the working condition of multiple function modules of secondary radar in real time, as long as digital video should
Answer press that symbol is apparent from be divided into the right and left, it is symmetrical, do not mix without intersecting, so that it may judge that the pulse of receiver is special
Property is normal；As long as low confidence answering point is only present in the center of digital video, so that it may preliminary Σ, the Δ for judging receiver
It is normal than width characteristic；If the point distribution of digital video is continuous, centre does not have leak source, show answer signal signal-to-noise ratio height,
Receiver amplifying circuit is working properly；If the point of digital video is evenly distributed, show that antenna rotation rate is uniform, bearing signal is normal
Etc..Digital video not only reflects the raw information, characteristic and quality of target response signal, it is often more important that secondary radar
The entire receiving channel state of antenna, feeder line, receiver, signal processing provides real time monitoring means, is the failure of secondary radar
Diagnosis provides very big help.Digital video increases the information content that answer signal is shown, need not but increase dedicated hardware
Equipment safeguards interface and the program of display terminal by modification, increases the information share space between signal processing and data processing,
The display of digital video is achieved that on display terminal in original safeguard.
Description of the drawings
Fig. 1 secondary radar echo signal flow diagrams.
The type of Fig. 2 secondary radar answer signals.
The non-monopulse secondary radar interception principle schematics of Fig. 3.
The principle schematic of Fig. 4 monopulse secondary radar interceptions.
The definition of Fig. 5 secondary radar transponder pulses.
Specific embodiment
Further detailed description is done to the present invention below in conjunction with the accompanying drawings.
According to the operation principle of secondary radar, the secondary radar on ground receives inquiry letter to request signal is sent out in the air
Number answering machine make response.Answer signal by the burst blocks that arrange according to certain rules into, train of pulse composition referring to Fig. 5,
By pulsewidth be 0.45 μ S, each pulse position forward position postpones 1.45 μ S, 15 pulse positions of 20.3 μ S of total occupy-place are formed, in specified arteries and veins
There is pulse to represent being encoded to " 1 " for this on position, no pulse represents being encoded to " 0 " for this.1st pulse of 15 pulses be
It is frame pulse that F1 and last 1 pulse, which are F2, F1 and F2, is always " 1 ", is identified there are a response, and remaining 13 are
Encoding the response.
Secondary radar usually on radar target display terminal, with mark or flight path come display target for information about, pipe
The point mark or flight path information realization airport monitoring or en route control that system is provided centrally through radar.To obtain than mark or flight path more
Transponder pulse according to distance, orientation can completely be shown, realizes that secondary radar is former by detailed target information on the screen
Beginning video is shown.Original video contains much information, and renewal speed is fast, it usually needs special video display and video driver electricity
Road could be shown.To simplify equipment, and retain effective presentation of information, we are by 1 response, 1 arteries and veins of corresponding 1 train of pulse
Expression is brought, specific method is that the identification of F1, F1 frame is first carried out to transponder pulse, only includes the train of pulse of F1, F2 frame
A response is just confirmed as, its symbol and confidence information are further determined that determining response, a response corresponds to a point
Show that the digital video of i.e. secondary radar is shown on the screen according to distance, orientation.The target information that digital video is shown
More rich, more more detailed than a mark, flight path, than original video relative simplicity, but symbol more increased than original video, confidence level are believed
Breath has highly important effect to the real-time monitoring of secondary radar equipment state and fault location, and need not increase hardware into
This, by changing software, digital video display function is can be achieved with maintenance display terminal.
Monopulse secondary radar answer signal and poor ratio (Σ/Δ) has positive and negative and low confidence differentiation, in number
We represent the positive and negative and low confidence with poor ratio with different colours when video is shown, it is possible to very clear resolution target
Positioned at the left side of antenna beam, the right or centre position.And for non-monopulse secondary radar, there is no Δ receiving channel, response
Signal just without positive and negative point, also without the definition of low confidence, corresponds to the digital video of each response by a kind of point of color
It forms.So digital video is suitable for pulse and the response message of non-monopulse secondary radar is shown, display example can be found in
Fig. 2.The position that residence time is limited in wave beam due to target, occurs is random, so the target having in digital video is not low
Degree of putting answering point, some targets have low confidence response, but since low confidence region is relatively narrow, have been only possible to 1 response and have fallen
Low confidence region.The example shown in Fig. 2 has 11 responses, 5 responses on the wave beam left side, 5 responses on the right of wave beam, in
Between 1 response fall in low confidence region.Due to secondary radar inquiry be A, C mode alternately, so transponder pulse string
Coding be also alternate.
The present invention provides a kind of secondary radar digital video display methods：Signal processing completes response decoding and obtains response
After target information, by the distance (16bits) of response target, orientation (14bits), symbol (1bit), confidence level (1bit) successively
It is written in dual port RAM, this dual port RAM is shared for signal processing with data processing, is divided into the region of 2 equal sizes.At signal
Reason generates an interruption in each inquiry period starting, after data processing responds this interruption, is read from 1 region of dual port RAM
The answer signal that the last inquiry period obtains is taken, at the same time, write-in is double in real time by the answer signal currently generated for signal processing
Another 1 region of mouth RAM ensures that 2 regions of dual port RAM are in the state of reading and write-in respectively.Data processing obtains
After answer signal, be written after answer signal is resequenced by the sequence that orientation is ascending, same azran is near and far
Digital video shows list.
Data processing and safeguarding is connected by local area network between display terminal computer, according on display control interface
Control command, select digital video display when, data processing timing by digital video show list in answer signal pass through
Network, which is sent to, safeguards display terminal, safeguard display terminal by the sequence of azimuth-range by answer signal with the side of digital video
Formula is shown on the screen；When non-selected digital video is shown, data processing and safeguard that there is no need to transmit between display terminal
Answer signal only transmits point, flight path signal and equipment state signal.Since the information content of answer signal is bigger, data update
Soon, it when secondary radar equipment is working properly, is not concerned with during equipment state (such as unattended, night), may be selected not show number
Video mitigates the processing load of equipment.When we pay close attention to equipment state, especially device fails, so that it may selection display
Digital video, by observing digital video, helping to pinpoint the problems or pressing symbol very to fault location, such as digital video answering point
Clearly be divided into the right and left, it is symmetrical, without intersect do not mix, so that it may judge that the pulse characteristic of receiver is normal, if
The point distribution of digital video is continuous, intermediate without leak source, shows answer signal signal-to-noise ratio height, receiver amplifying circuit works just
Often；If the point of digital video is evenly distributed, show that antenna rotation rate is uniform, bearing signal is normal；If digital video is intermittent,
Illustrate that answer signal amplitude is very weak or answer signal receives interference or blocks signal is caused to receive imperfect or receiver amplification electricity
Road gain is too small, back noise is too big etc..
It safeguards the target display interface of display terminal, usually only has the display option of a mark, flight path, control is given with radar
The target information option at center is similar.Invention increases digital videos to show content, so also phase on target display interface
The display option of digital video should be increased, while increase related control program, come complete control command generate and send,
The connection of network, the sending and receiving of data packet, the functions such as digital video is shown.
After safeguarding the function that display terminal shows digital video in selection, the related letter of answer signal is obtained from data processing
Breath including distance (16bits), orientation (14bits), symbol (1bit), confidence level (1bit), shows control program according to distance, side
Position information draws answering point on the corresponding position of target display interface；According to symbol, confidence information, answering point takes different face
Color, the red left side for corresponding to wave beam of negative sign, positive sign correspond to the right of wave beam with blue, and it is corresponding that low confidence corresponds to green
In beam center or near.Since the position that each answer signal occurs in wave beam is random, but time interval is fixed, wave
Beam width is fixed, so the number that the inswept target of wave beam generates response is substantially stationary, falls the number on beam positional axis both sides
Substantially half is respectively accounted for, and the response of low confidence occurs at random, may there is 1 low confidence response in 1 group of response, it may
There is no low confidence response (being the situation for having 1 low confidence response as shown in Figure 2).
The foregoing is only a preferred embodiment of the present invention, is not restricted to the present invention, for the technology of this field
For personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, that is made any repaiies
Change, equivalent replacement, improvement etc., should be included within scope of the presently claimed invention.
Claims (2)
1. a kind of secondary radar digital video display methods, it is characterized in that：After signal processing completes transponder pulse extraction, to pulse
Signal carries out frame identification, and the train of pulse for only including F1, F2 frame is just confirmed as a response, is represented with 1 pulse
This response；F1 is the 1st pulse in train of pulse, and F2 is last 1 pulse in train of pulse；
After decoding obtains symbol and the confidence information of response, the distance of the response, orientation, symbol, confidence level are written successively
In dual port RAM, this dual port RAM is shared for signal processing with data processing, is divided into the region of 2 equal sizes；Signal processing exists
Each inquiry period starting generates an interruption, after data processing responds this interruption, is read from 1 region of dual port RAM
The answer signal that a inquiry period obtains, at the same time, dual port RAM is written in the answer signal currently generated by signal processing in real time
Another 1 region, that is, ensure that 2 regions of dual port RAM are in the state of reading and write-in respectively.Data processing obtains response letter
After number, answer signal is regarded by write-in number after the sequence rearrangement that orientation is ascending, same azran is near and far
Frequency shows list；And it is shipped regularly to display terminal.
2. the method that secondary radar digital video according to claim 1 is shown, it is characterized in that：The display terminal is
It safeguards display terminal, safeguards that display terminal according to the distance of answer signal, orientation, symbol and confidence level, is pressed on display interface
Predetermined color draws response, and there are pulses, show the digital video of secondary radar.
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Cited By (1)
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| CN109459730A (en) * | 2018-10-31 | 2019-03-12 | 中国船舶工业系统工程研究院 | A kind of display fatal position location fill method based on virtual bearing swing |
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