CN107966698A - Secondary radar equipment and signal processing method - Google Patents
Secondary radar equipment and signal processing method Download PDFInfo
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- CN107966698A CN107966698A CN201711039517.1A CN201711039517A CN107966698A CN 107966698 A CN107966698 A CN 107966698A CN 201711039517 A CN201711039517 A CN 201711039517A CN 107966698 A CN107966698 A CN 107966698A
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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
- G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
- G01S13/74—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
- G01S13/76—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein pulse-type signals are transmitted
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- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
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- General Physics & Mathematics (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The present invention relates to secondary radar equipment and signal processing method.The present invention provides a kind of signal decoding method sorted using multiplex (MUX), including：According to the amplitude and orientation of signal, the signal is distributed in N path channels according to predetermined sorting strategy, wherein N is the positive integer more than or equal to 2；And the signal to being distributed in each path channels in the N path channels is respectively into row decoding.
Description
Technical field
The present invention relates to field of signal processing, more particularly to a kind of signal decoding method using multiplex (MUX) sorting and
Secondary radar equipment.
Background technology
With the development of aeronautical technology, MARKXII series secondary radar and S mode secondary radar (SSR) equipment obtain greatly
Amount popularization, is widely used in military and civil aviaton field.Secondary radar can ensure to ask by repeat queries or information checking
Ask end and responding terminal reliably communication and identification, and the passive reconnaissance equipment based on secondary radar is hidden since its work characteristics has
Covering property and non-cooperating, therefore received information cannot be docked and verified or error correction, it can not require to initiate repeated communications.On
State the difficult accuracy for causing to be difficult to ensure that the passive scouting based on secondary radar signals acquisition information.Especially in complicated electromagnetism
A large amount of false targets often occur under environment, or intercept incomplete information.
Current secondary radar signals detection process includes small-signal filtering, the detection of pulse frame, interleaved signal detection, width
Spend consistency detection etc., final output testing result.The greatest problem of the detection method is that multiple deinterleaving Resolving probiems are obtained
Bad, multiple interleaved signal often can not be detected all, and signal pairing is also difficult to realize under multi-parameter.
Traditional interpretation method mostly according to specified signal pattern to receiver video input signals into row decoding, translate
The amplitude coincidence of each pulse is detected further according to signal amplitude value after signal pattern, detection exports decoding after passing through
Mark, and the amplitude of decoded signal and orientation values are used as using the amplitude of P1 pulses and orientation values.The main problem of this method has：It is right
In the very big channel of signal density, channel progress signal interpretation all the way, which is only used only, can not fully filter to go out in information bits of coded
Existing disturbing pulse；Meanwhile simply carrying out amplitude coincidence detection can cause the signal on same rang ring not efficiently separate；
Also, although the P1 pulses of decoding output are reference signals, since measurement of the receiver to amplitude and direction parameter exists
Error, therefore only the parameter of whole decoded signal and unreliable is used as using only the parameter value of P1 pulses, it is possible to cause terminal
There are larger shake for the signal amplitude and orientation of display；In addition, not only algorithm is complicated during processing multiple solution signal interleaving, at the same time
The tuple of deinterleaving is also relatively limited.
The content of the invention
To solve the above-mentioned problems, the present invention proposes a kind of new signal processing method, and this method utilizes multiplex (MUX) point
Choosing carries out signal interpretation, it can meet the needs of de-interleaved signal to greatest extent, solve classical signal processing well
During various problems.
According to an aspect of the invention, there is provided a kind of signal decoding method sorted using multiplex (MUX), including：Root
It is believed that number amplitude and orientation, the signal is distributed in N path channels according to predetermined sorting strategy, wherein N to be more than or
Positive integer equal to 2；And the signal to being distributed in each path channels in the N path channels is respectively into row decoding.
In one embodiment, the signal includes pulse.
In another embodiment, it is described the signal is distributed to N path channels according to predetermined sorting strategy to include：Will
Enter the pulse of the first path channels in the N path channels at first as reference pulse；By the amplitude of succeeding impulse and orientation with
The amplitude and orientation of the reference pulse are compared, and calculate Magnitude Difference and orientation difference；If the and Magnitude Difference
With the orientation difference respectively in predetermined amplitude thresholding and preset bearing thresholding, then the succeeding impulse is distributed to described
In one path channels.
In another embodiment, the method further includes：By first not distributed pulse to first path channels
It is distributed in the second path channels in the N path channels, and screen succeeding impulse to distribute using the pulse as reference pulse
Into second path channels.
In another embodiment, the method further includes：By the not distributed preceding N-1 path channels in the N path channels
In pulse be all distributed in the N path channels in the N path channels.
In another embodiment, N=4.
In another embodiment, to the amplitude of all pulses that is distributed in each path channels in the N path channels and
Orientation is weighted average, and amplitude and orientation using average amplitude and general bearing as all pulses in the path channels.
In another embodiment, to each path channels in the N path channels, coding identification is individually exported.
In another embodiment, to each path channels in the N path channels, when meeting following either condition, release
The channel, and all pulses in the channel are emptied, to wait new pulse to be distributed to the channel：Translated from channel output
Code had identified the first preset time；Do not have from first pulse enters the channel in the second preset time new pulse into
Enter the channel；And existing multiple pulses enter the channel, but when last pulse is default into the channel the 3rd
Interior no output coding identification.
According to another aspect of the present invention, there is provided a kind of secondary radar equipment, including：Receiver, believes for receiving
Number；Distributor, for the amplitude and orientation according to the signal, N roads are distributed to according to predetermined sorting strategy by the signal
In channel, wherein N is the positive integer more than or equal to 2；And N number of decoder, with the N path channels correspond, for pair
The signal in each path channels in the N path channels is distributed to respectively into row decoding.
Compared with prior art, one or more of such scheme embodiment can have the following advantages that or beneficial to effect
Fruit：Channel is divided into row decoding using multi-Dimensional parameters thresholding, can meet de-interleaved signal and signal pairing to greatest extent
Demand, that improves direction detection equipment detects receipts ability；Meanwhile scouting can be improved using signal pulse parameter weighting average algorithm
Direction-finding equipment detects the Stability and veracity for receiving signal parameter；In addition, it is adapted to difference by increasing or decreasing channel way
Signal processing requirement.
Other features and advantages of the present invention will be illustrated in the following description, and partly becomes from specification
It is clear that or understood by implementing the present invention.The purpose of the present invention and other advantages can be by wanting in specification, right
Specifically noted structure is sought in book and Figure of description to realize and obtain.
Brief description of the drawings
Attached drawing is used for providing a further understanding of the present invention, and a part for constitution instruction, the reality with the present invention
Apply example to be provided commonly for explaining the present invention, be not construed as limiting the invention.In the accompanying drawings, identical component uses identical attached
Icon is remembered, and attached drawing is not drawn according to actual ratio.
Fig. 1 is the schematic diagram according to the exemplary channel of one embodiment of the invention sorting strategy.
Fig. 2 is the schematic block diagram according to the secondary radar equipment of another embodiment of the present invention.
Embodiment
Carry out the embodiment that the present invention will be described in detail below with reference to accompanying drawings and embodiments, how the present invention is applied whereby
Technological means solves technical problem, and that reaches technique effect realizes that process can fully understand and implement according to this.Need to illustrate
As long as not forming conflict, each embodiment in the present invention and each feature in each embodiment can be combined with each other,
The technical solution formed is within protection scope of the present invention.
Meanwhile in the following description, for illustrative purposes and numerous specific details are set forth, to provide to of the invention real
Apply the thorough understanding of example.It will be apparent, however, to one skilled in the art, that the present invention can not have to tool here
Body details or described ad hoc fashion are implemented.
The following detailed description of signal processing method according to an embodiment of the invention.The signal includes one or more arteries and veins
Punching.This method is based on the passive scouting of secondary radar, mainly includes the following steps.
Step 1：Its spatial electromagnetic Bomi degree is analyzed for different frequent points signal, in conjunction with direction detection equipment day
The combined factors such as line beam angle, receiver orientations measurement error are analyzed, and determine to carry out the channel quantity of channel division.Can also
Channel quantity is determined according to historical experience.For a certain fixed frequency point X, it is assumed that can divide four channel Chnl1, Chnl2,
Chnl3, Chnl4, and signal processing method according to the present invention is illustrated with this.
Step 2：When signal-processing board works, to enter the pulse of Chnl1 channels at first as benchmark P1, by its amplitude a1
With orientation o1 as benchmark, using predetermined amplitude threshold Amp_thd and orientation thresholding Ort_thd, will meet after P1 pulses
The pulse of amplitude range a1-Amp_thd~a1+Amp_thd and bearing range o1-Ort_thd~o1+Ort_thd all divide
It is sent to the first channel Chnl1.In spatial distribution, the signal distributions of Chnl1 channels are one section of cone area.
Step 3：Reference pulses of the first pulse P2 of Chnl1 channels as Chnl2 channels is will not belong to, further according to width
Thresholding Amp_thd and orientation thresholding Ort_thd screenings are spent into the signal in Chnl2 channels.
Step 4：It will not belong to benchmark arteries and veins of the first pulse P3 of Chnl1 channels and Chnl2 channels as Chnl3 channels
Punching, the signal in Chnl3 channels is entered further according to amplitude threshold Amp_thd and orientation thresholding Ort_thd screenings.
Step 5：All pulses that will not belong to Chnl, Chnl2 and Chnl3 channel are put into Chnl4 channels.
Step 6：Each path channels correspond to a decoder, each decoder individually exports coding identification, while to this
The amplitude of all pulses and orientation values are weighted average in channel, and using averaged amplitude value and average orientation values as this
The range value and orientation values of all pulses in channel.The decoder is, for example, the decoder that can solve triple churning.
Step 7：The coding identification and parameter value of the output of all 4 channels are carried out integrating output.
Step 8：130us after any channel output coding identification, or first pulse enter in the channel and 25us and do not have
New signal is dispensed to the channel, or multiple pulses enter without output coding identification in the channel but 130us, then removing should
The right to use of channel signal, discharges the channel.
Step 9：All pulse datas all empty in the channel after channel release, wait new pulse to be distributed to the letter
Road.
It should be noted that each step is not all required above, can be omitted part therein according to actual conditions walks
Suddenly, this will be obvious to those skilled in the art that also, above specific number it is merely exemplary, in difference
In the case of can be other numerals, and do not limit the scope of the invention.
There is significant advantage using weighted average when the range value and orientation values of pulse are calculated in above-mentioned steps 6：Knot
The signal parameter jitter amplitude that fruit is is significantly less than receiving device measurement error.If simply use P1 pulse parameter conducts
Signal parameter, then the signal parameter jitter amplitude obtained are shaken according to receiving device measurement error.
Specific number in above-mentioned steps 8 is so obtained：Assuming that on X frequency points secondary radar signals maximum adjacent frame
Frame pulse distance (that is, the time interval between individual pulse in signal sequence) is 20us, maximum signal length (that is, is believed
The time domain length of number sequence) it is 120us, these parameters are suitably relaxed to obtain with parameter 25us and 130us in step 8.Not
In same embodiment, according to different maximum adjacent frame pulse distances and different maximum signal lengths, above-mentioned parameter
Can differently it be configured.
Fig. 1 is the schematic diagram according to the exemplary channel of one embodiment of the invention sorting strategy.As shown in Figure 1, received
Input signal be distributed to respectively in channel Chnl1, Chnl2, Chnl3 or Chnl4 according to impulse amplitude and pulse orientation.It is false
If channel Chnl1 does not have effective coding formats, first and second pulses of channel Chnl2 can export an efficient coding
Signal, the first of channel Chnl3 and the 3rd pulse can export an efficient coding signal, channel 4 only has individual signals, then
4 channel respective release times are respectively according to above-mentioned steps 8：Channel Chnl1 is released from the 4th pulse after 130us
Put, channel Chnl2 130us from the 3rd pulse are released, and the 130us from the 3rd pulse of channel 3 is released, and channel 4 is certainly
First pulse is released after playing 25us.
Compared with the signal processing method of existing direction detection equipment, the embodiment of the invention is not increasing additionally firmly
On the premise of part cost, signal processing method is optimized so that direction detection equipment using the present invention can be increasingly complex
Electromagnetic environment under accurately intercept and capture target information.In addition signal processing method of the invention also has the scalability strong with transplantability
The characteristics of, it is adapted to different signal processing requirements by increasing or decreasing signal processing channels.
Fig. 2 is the schematic block diagram according to the secondary radar equipment of another embodiment of the present invention.As shown in Fig. 2, secondary thunder
Include up to equipment 100：Receiver 102, for receiving signal；Distributor 104, for the amplitude and orientation according to the signal,
The signal is distributed in N path channels according to predetermined sorting strategy, wherein N is the positive integer more than or equal to 2；And N
A decoder 1061 ... 106N, corresponds with the N path channels, for being distributed to often believing all the way in the N path channels
Signal in road is respectively into row decoding.
Although by reference to preferred embodiment, invention has been described, is not departing from the situation of the scope of the present invention
Under, various improvement can be carried out to it and component therein can be replaced with equivalent.Especially, to be rushed as long as there is no structure
Prominent, items technical characteristic mentioned in the various embodiments can be combined in any way.The invention is not limited in text
Disclosed in specific embodiment, but all technical solutions including falling within the scope of the appended claims.
Claims (10)
1. a kind of signal decoding method sorted using multiplex (MUX), including：
According to the amplitude and orientation of signal, the signal is distributed in N path channels according to predetermined sorting strategy, wherein N is
Positive integer more than or equal to 2；And
To the signal that is distributed in each path channels in the N path channels respectively into row decoding.
2. signal decoding method according to claim 1, wherein, the signal includes pulse.
3. signal decoding method according to claim 2, wherein, it is described to divide the signal according to predetermined sorting strategy
Being dealt into N path channels includes：
Using the pulse of the first path channels entered at first in the N path channels as reference pulse；
By the amplitude of succeeding impulse and orientation compared with the amplitude and orientation of the reference pulse, calculate Magnitude Difference and
Orientation difference；And
If the Magnitude Difference and the orientation difference are respectively in predetermined amplitude thresholding and preset bearing thresholding, after described
Continuous pulse is distributed in first path channels.
4. signal decoding method according to claim 3, further includes：
First not distributed pulse to first path channels is distributed in the second path channels in the N path channels,
And succeeding impulse is screened to be distributed in second path channels using the pulse as reference pulse.
5. signal decoding method according to claim 4, further includes：
N pulse in the not distributed preceding N-1 path channels in the N path channels being all distributed in the N path channels
In path channels.
6. signal decoding method according to claim 1, wherein, N=4.
7. signal decoding method according to claim 2, wherein, to each path channels being distributed in the N path channels
In all pulses amplitude and orientation be weighted it is average, and using average amplitude and general bearing as the institute in the path channels
There are the amplitude and orientation of pulse.
8. signal decoding method according to claim 2, wherein, it is individually defeated to each path channels in the N path channels
Go out coding identification.
9. signal decoding method according to claim 8, wherein, to each path channels in the N path channels, meeting
During following either condition, the channel is discharged, and all pulses in the channel are emptied, to wait new pulse to be distributed to this
Channel：
From the channel exports coding identification first preset time；
There is no new pulse to enter the channel in the second preset time from first pulse enters the channel；And
Existing multiple pulses enter the channel, but not defeated in the 3rd preset time from last pulse enters the channel
Go out coding identification.
10. a kind of secondary radar equipment, including：
Receiver, for receiving signal；
Distributor, for the amplitude and orientation according to the signal, N roads are distributed to according to predetermined sorting strategy by the signal
In channel, wherein N is the positive integer more than or equal to 2；And
N number of decoder, corresponds with the N path channels, for being distributed in each path channels in the N path channels
Signal is respectively into row decoding.
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| CN109725307A (en) * | 2018-12-13 | 2019-05-07 | 四川九洲空管科技有限责任公司 | A kind of second set response data-link interpretation method of frame shearing |
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