CN110764063B - Radar signal sorting method based on combination of SDIF and PRI transformation method - Google Patents
Radar signal sorting method based on combination of SDIF and PRI transformation method Download PDFInfo
- Publication number
- CN110764063B CN110764063B CN201910976041.7A CN201910976041A CN110764063B CN 110764063 B CN110764063 B CN 110764063B CN 201910976041 A CN201910976041 A CN 201910976041A CN 110764063 B CN110764063 B CN 110764063B
- Authority
- CN
- China
- Prior art keywords
- pri
- sorting
- radar
- pulse
- signals
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 66
- 238000011426 transformation method Methods 0.000 title claims abstract description 8
- 238000006243 chemical reaction Methods 0.000 claims abstract description 44
- 230000008030 elimination Effects 0.000 claims description 8
- 238000003379 elimination reaction Methods 0.000 claims description 8
- 238000001208 nuclear magnetic resonance pulse sequence Methods 0.000 claims description 5
- 238000004364 calculation method Methods 0.000 claims description 4
- WLWIMKWZMGJRBS-UHFFFAOYSA-N primin Chemical compound CCCCCC1=CC(=O)C=C(OC)C1=O WLWIMKWZMGJRBS-UHFFFAOYSA-N 0.000 claims description 4
- 238000012545 processing Methods 0.000 claims description 3
- 238000004422 calculation algorithm Methods 0.000 abstract description 20
- 230000000694 effects Effects 0.000 abstract description 6
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 238000000926 separation method Methods 0.000 description 7
- 238000007689 inspection Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 5
- 238000013461 design Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000007865 diluting Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 108010076504 Protein Sorting Signals Proteins 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000010845 search algorithm Methods 0.000 description 1
Classifications
-
- 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
- G01S7/36—Means for anti-jamming, e.g. ECCM, i.e. electronic counter-counter measures
-
- 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
- G01S7/023—Interference mitigation, e.g. reducing or avoiding non-intentional interference with other HF-transmitters, base station transmitters for mobile communication or other radar systems, e.g. using electro-magnetic interference [EMI] reduction techniques
Abstract
The invention belongs to the technical field of electronic countermeasure, and particularly relates to a radar signal sorting method based on combination of an SDIF (secure digital interface) and a PRI (pulse-with-interference) transformation method, which enables a search effect to be faster and more obvious. The method comprises the following steps: pre-grouping radar signals; establishing an arrival time level difference histogram for the pre-sorted radar groups by using an SDIF method; according to the time domain characteristics of the radar signal model, rapidly searching and extracting radar signals; establishing a first-level difference histogram to rapidly analyze the spread signal; judging whether complex type radar signals remain; and inquiring sorting results of all modules. The invention has the beneficial effects that: the pre-sorting and the main sorting are combined, the SDIF and the PRI conversion method are combined as the main sorting, the SDIF part carries out quick and effective sorting on conventional signals, spread signals, inter-pulse agile signals and pulse group agile signals in the electromagnetic environment of the complex radar, the PRI conversion method part sorts the rest shaking signals, and each part algorithm plays roles and plays roles respectively, so that an effective and quick comprehensive sorting algorithm is formed.
Description
Technical Field
The invention belongs to the technical field of electronic countermeasure, and particularly relates to a radar signal sorting method based on combination of an SDIF (secure digital interface) and a PRI (pulse-with-interference) transformation method, which enables a search effect to be faster and more obvious.
Background
With the rapid development of radar technology, the complexity of a battlefield electromagnetic environment is further increased, the battlefield electromagnetic environment is changeable, the signal variety is various, the radar signal density reaches millions or even tens of millions per second, the complex electromagnetic environment is more and more difficult to deal with by combining the traditional pre-sorting technology with a single-parameter sorting algorithm, and the sorting performance and the sorting speed are in need of improvement. The traditional pre-sorting technology mainly utilizes parameters in the description words in the radar signal pulse, and is matched with tolerance to carry out simple grouping, so that one agile radar signal is easily divided into a plurality of radar signals in a staggered manner, and is limited by the set PRI sorting range, and if the preset sorting range is larger, the large PRI signal and the small PRI signal are easily interfered with each other; if the preset sorting range is small, valuable radar signals are missed. Common single parameter sorting algorithms are spread correlation, difference histogram, cumulative difference histogram (CDIF), sequential difference histogram (SDIF), and PRI transform.
The extended association method is the earliest applied algorithm in single parameter signal separation, is also the most basic, and is suitable for the early simple radar electromagnetic environment; the CDIF method is a radar signal sorting algorithm commonly applied at present, based on the arrival time difference principle, great improvement is made on the basis of a statistical histogram, the arrival time difference values of different levels are accumulated, a reasonable detection threshold is set, and harmonic waves are restrained; the SDIF is an improved version of CDIF, the arrival time difference is not accumulated any more, the calculated amount is reduced by half compared with CDIF, but the detection threshold is difficult to set and the jittered radar signals cannot be sorted; the original sequence searching algorithm has high time complexity and is difficult to search for the spread signals; the original spread inspection flow is complex; the PRI conversion method can sort part of jitter signals, has strong sub-harmonic resistance, but is difficult to sort spread signals, has huge operand and is difficult to be practically applied. The learner introduces the idea of changing the time starting point and the overlap box into the PRI conversion method, so that the PRI conversion method has the capability of sorting large jitter signals, but the PRI estimation accuracy is poor, and error sorting is easy to cause. In an actual radar signal sorting system, how to comprehensively utilize each algorithm, and improving the sorting effect accuracy while improving the sorting speed is a current problem to be solved urgently.
Disclosure of Invention
The invention aims to provide a radar signal sorting method based on combination of an SDIF (serial digital interface) and a PRI (pulse-with-noise) transformation method.
The purpose of the invention is realized in the following way:
A radar signal sorting method based on combination of SDIF and PRI transformation method comprises the following steps:
step 1: setting a long period of observation time, a short period of observation time and a short period of observation time, 1000ms and 10ms, establishing a histogram of each parameter by utilizing parameters such as arrival direction DOA, carrier frequency CF, pulse width PW and the like of pulse descriptors of radar signals, and pre-grouping the radar signals;
step 2: according to the pre-sorting result of the step 1, an arrival time level difference histogram is established for the pre-sorted radar groups by utilizing an SDIF method, the initial level difference C is 1, and when the peak value of the histogram exceeds a threshold value, the arrival time difference is judged to be a possible radar signal PRI;
Step 3: performing sequence search according to the PRI estimated in the step 2, rapidly searching and extracting radar signals according to the time domain characteristics of a radar signal model, and extracting a complete ragged radar signal at a time;
Step 4: if the searched PRI has the same value, preliminarily considering that a spread signal exists, and restoring a spread signal pulse train according to a time domain sequence to establish a level of a difference histogram to rapidly analyze the spread signal;
step 5: judging whether a complex type radar signal remains in an electromagnetic space of the extracted radar signal, such as a large-range dithering radar signal, if so, adopting a multistage PRI box structure, such as 5%,10% and 15%, and performing discrete form PRI conversion on a residual pulse sequence in the group;
step 6: and inquiring the sorting results of all modules, finishing the information output of radar signals, such as radar signal types, PRI and the like, and realizing sorting.
The step 1 specifically comprises the following steps: removing noise points; preliminary pre-sorting by utilizing parameters such as pulse width, arrival angle and the like; the frequency agile signals are distinguished and the other types of signals are pre-sorted.
In the step 2, when the number of peaks exceeding the threshold is not the same, that is, a plurality of PRI values exceed the threshold at the same time, pulse trial search is firstly carried out according to half of the corresponding PRI values, if all search fails, the next-stage difference histogram is directly carried out, and then whether the PRI value exceeds the threshold is detected.
The threshold in step 2 is determined by calculation using the following formula:
Tthreshold＝α(E-C)e-λτ
Wherein lambda is the average occurrence probability of radar signals in unit time, E is the number of current pre-grouped total radar pulses, C is the number of ongoing difference stages, (E-C) is the number of pulse intervals, alpha is related to the pulse loss rate, and tau is the total time interval, namely the pulse acquisition time.
The PRI overlap bin width in step 5 is determined by the larger value between the base bin width and the bin center jitter value, base bin width b= (PRI max-PRImin)/K, and the bin center jitter value is determined by the bin center position K L together with the bin jitter rate epsilon i, where the L-th overlap bin width constructed at the bin jitter rate epsilon i is b iL＝max([b,2εikiL at the L-th bin center position K L＝(L-1/2)·(PRImax-PRImin)/K+PRImin.
In the step 5, the threshold setting should consider the observation time principle, the subharmonic elimination principle and the noise elimination principle, and the maximum value of the three should be selected for the threshold setting of the overlap box at the L-th position, so that the threshold setting of the overlap box at the L-th positionWherein α, β, γ is manually set (e.g., α=0.34, β=0.17, γ=3), and is related to the number of overlapping bin dithering rates, and N is the total number of radar pulses in the current environment.
The invention has the beneficial effects that:
1. The pre-sorting and the main sorting are combined, the SDIF and the PRI conversion method are combined as the main sorting, the SDIF part carries out quick and effective sorting on conventional signals, spread signals, inter-pulse agile signals and pulse group agile signals in the electromagnetic environment of the complex radar, the PRI conversion method part sorts the rest shaking signals, and each part algorithm plays roles and plays roles respectively, so that an effective and quick comprehensive sorting algorithm is formed;
2. Introducing a statistical histogram and a multi-level sorting idea into the traditional pre-sorting, realizing the sorting of the frequency agile signals by using the carrier frequency statistical histogram, preventing the occurrence of batch increase, and adopting long and short observation time and a two-stage threshold to prevent the PRI signals in a large and small range from interfering with each other;
3. The step difference histogram in the sequence difference histogram process is utilized to carry out preliminary spread signal judgment on the signal pulse being extracted, when the arrival time of all the pulses is traversed in the predicted arrival time range, the time domain characteristics of the radar signal sequence pulse model are combined, the complexity of the traversing time is greatly reduced, the capability of quickly searching multiple frequency spread radar signals is realized, and the searching speed and searching effect are improved;
4. Introducing the statistical histogram concept into the spread inspection, and rapidly obtaining subcycle information by restoring an original heavy frequency spread radar signal and utilizing the statistical histogram, wherein the time complexity and the space complexity are both O (n), so that the real-time performance of the spread inspection is improved;
5. The multi-stage PRI box structure is firstly provided to be applied to a PRI conversion method, so that a jitter signal enters a PRI box matched with the jitter rate as much as possible, the defect that the estimation precision and the estimation range of a single PRI box cannot be achieved simultaneously is overcome, and the PRI estimation precision is improved while the large-range jitter signal is ensured to be sorted.
Drawings
FIG. 1 is a flow chart of the overall sorting algorithm of the present invention;
FIG. 2 is a flow chart of a pre-selection algorithm of the present invention;
FIG. 3 is a flow chart of the SDIF-section algorithm of the present invention;
FIG. 4 is a partial flow chart of the PRI transform method in an embodiment of the present invention;
fig. 5 is a graph of complex electromagnetic environment parameters and sorting results.
Detailed Description
The invention is further described below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical aspects of the present invention, and are not intended to limit the scope of the present invention.
According to the radar signal sorting method based on combination of the SDIF and the PRI conversion method, the whole flow is shown in fig. 1, the pre-sorting is shown in fig. 2, the signal density is greatly reduced, the follow-up main sorting pressure is relieved, the SDIF algorithm is used for estimating and extracting common heavy frequency signals, spread signals and agile signals from the pre-sorting result, the spread inspection is carried out, the SDIF partial algorithm flow is shown in fig. 3, if the jitter signals still exist in the pre-grouping, the pre-sorting is carried out by the PRI conversion method, and the PRI conversion method partial flow is shown in fig. 4.
The method comprises the following steps:
Step 1: setting a long period of observation time and a short period of observation time (such as 1000ms and 10 ms), establishing a histogram of each parameter by using pulse descriptors of radar signals such as parameters of arrival direction DOA, carrier frequency CF, pulse width PW and the like, pre-grouping the radar signals, and distinguishing the frequency agile signals from other radar signals and pre-sorting the radar signals;
Step 1-1: noise points are removed. The radar signal parameters such as carrier frequency and pulse width of noise points are randomly distributed, a carrier frequency statistical histogram and a pulse width statistical histogram are respectively established according to tolerance, according to the vertical axis height of the two histograms, a threshold is set to respectively clear isolated noise points and interference points, for example, the tolerance of the carrier frequency statistical histogram is 10MHz, the tolerance of the pulse width statistical histogram is 0.5 mu s, pulse points with the height lower than 10 are used as noise points, points with the height lower than 150 are used as interference points in the pre-sorting aiming at short observation time, points with the height higher than 2000 are used as interference points in the pre-sorting aiming at long observation time, and the points are deleted from pulse description words;
Step 1-2: preliminary pre-sorting is performed by utilizing parameters such as pulse width, arrival angle and the like. And grouping pulse points of similar signals according to parameters such as pulse width, arrival angle and the like by combining tolerance according to the denoised pulse width and arrival angle statistical histogram, and preliminarily diluting the signals. The setting of the tolerance should include the jitter range of the signal pulse width and the arrival angle as far as possible so as to prevent the preliminary pre-selection from causing wrong separation, for example, the pulse width tolerance is set to be 3 mu s, and the arrival angle tolerance is set to be 0.5 degrees;
Step 1-3: the frequency agile signals are distinguished and the other types of signals are pre-sorted. The carrier frequency statistical histogram is utilized in the pre-sorting result of pulse width and arrival angle, a threshold is set to distinguish the frequency agile signals, the signals lower than the threshold are judged to be frequency agile signals, the signals higher than the threshold are divided into other radar signal groups of a plurality of different carrier frequencies according to carrier frequency tolerance, for example, the carrier frequency tolerance is set to be 100MHz, and the threshold is set according to the observation time:
Tthreshold＝βT/τ β∈(0,1)
Wherein T is the observation time, tau is the median value of the current sorting PRI range, two PRI ranges in a short observation time are preset, for example, the PRI range in a short observation time is 0-200 mu s, the PRI range in a long observation time is 200-2000 mu s, and beta is a human set parameter.
Step 2: according to the pre-sorting result of the step 1, an arrival time level difference histogram (initial level difference C is 1, and highest level difference is 8) is established for the pre-sorted radar packets by utilizing an SDIF method, when the peak value of the histogram exceeds a threshold value, the arrival time difference is judged to be a possible radar signal PRI, when the number of the peak value exceeding the threshold is not only, namely, a plurality of PRIs exceed the threshold at the same time, pulse trial search is firstly carried out according to half of the corresponding PRIs, namely, according to the PRI search, whether 5 pulses can be searched or not, if all the search fails, the next level difference histogram is directly carried out, and whether the PRI value exceeds the threshold is detected.
The threshold is determined by calculation using the following formula:
Tthreshold＝α(E-C)e-λτ
Wherein lambda is the average occurrence probability of radar signals in unit time, E is the number of current pre-grouped total radar pulses, C is the number of ongoing difference stages, (E-C) is the number of pulse intervals, alpha is related to the pulse loss rate, and tau is the total time interval, namely the pulse acquisition time.
Step 3: performing sequence search according to the PRI estimated in the step 2, rapidly searching and extracting radar signals according to the time domain characteristics of a radar signal model, and extracting a complete ragged radar signal at a time;
step 3-1: according to the step 2, estimating a level difference histogram corresponding to PRI, searching the pulse number conforming to the PRI in the histogram;
step 3-2: determining a starting pulse position of the estimated PRI within the pulse descriptor;
Step 3-3: performing sequence searching, wherein in the searching process, the pulse position searched at this time is stored, and since the pulse position predicted at the next time is necessary to be after the pulse position searched at this time, the searching is directly started from the stored position at the next time of searching;
Step 3-4: after the search is finished, comparing the number of the pulses extracted in the search with the number of the coincidence PRI found in the level difference histogram, preliminarily judging whether the pulse is a spread signal according to the multiple relation of the pulse number and the PRI, and searching again at the next pulse of the starting pulse if the pulse is the spread signal.
Step 4: if the searched PRI has the same value, preliminarily considering that a spread signal exists, and restoring a spread signal pulse train according to a time domain sequence to establish a level of a difference histogram to rapidly analyze the spread signal;
Step 4-1: according to the PRI estimated value obtained in the step 2, in a certain tolerance, the parameter difference number is primarily judged according to the same PRI value number, and if the tolerance is 1 mu s;
step 4-2: the extracted pulse stream is searched by utilizing the sequence, and the original spread radar signal is restored according to the arrival time sequence;
Step 4-3: sequentially carrying out level one difference on the original spread radar signals, and carrying out histogram statistics;
Step 4-4: according to the parameter, if the parameter is 3, sequentially selecting 3 arrival time differences with higher frequency as sub-periods.
Step 5: judging whether complex type radar signals remain in the extracted radar signal electromagnetic space, if so, performing discrete form PRI conversion on the residual pulse sequences in the groups by adopting a multistage PRI box structure (such as 5%,10% and 15%);
Step 5-1: judging whether the pulse number in the space exceeds a threshold (if set to 20) after the current radar signal grouping electromagnetic space is subjected to SDIF separation and extraction, if yes, performing PRI conversion method separation, otherwise, skipping step 5;
step 5-2: respectively creating K overlapped PRI boxes constructed by a plurality of different jitter rates, wherein the jitter rates are epsilon 1、ε2、ε3(ε1<ε2<ε3 in sequence, if K is 300, 300 PRI overlapped boxes of 5%, 10% and 15% are respectively created, and initializing a PRI conversion array, a marking pulse stream array, a time starting point array and a marking time starting point array, wherein the array lengths are K;
step 5-3: let n=2, m=1, τ=t n-tm, judge whether arrival time difference τ is within the preset PRI range, if not, then m=m+1 again judges until m=n-1, if none of the arrival time differences is within the preset PRI range, let n=n+1 continue to carry out PRI range judgment;
Step 5-4: if the arrival time difference tau is within the preset PRI range, traversing each box from the first overlapped box with the jitter rate epsilon 1;
step 5-5: firstly, judging whether an arrival time difference tau is in an overlapped box range constructed by an L-th jitter rate epsilon 1, if so, adding one to an L-th position C L in a mark pulse stream array, judging whether the L-th position of a mark time starting point array is 0, and if not, not processing; if the position is 0, marking the position as a time starting point O k, and marking the corresponding position 1 of the time starting point array;
Step 5-6: the phase value is calculated, and the phase is calculated by using the formula of phase η 0＝(tn-Ok)/τ, wherein when (v=η 0 +0.4999 …) is rounded down to 1 or more than 2 and | (η 0/v)-1|<ζ0) (ζ 0 is a set positive value, such as 0.03), the current t n is taken as the time starting point.
Step 5-7: PRI conversion is carried out, the PRI conversion array D k is updated, and D k＝Dk+exp(2πiη0) is carried out;
Step 5-8: judging whether the arrival time difference tau enters the range of an L-th overlapped box constructed by epsilon 2 dithering rate, then carrying out the steps 5-5, 5-6 and 5-7, judging whether the arrival time difference tau enters the range of an L-th overlapped box constructed by epsilon 3 dithering rate, and the like, wherein after a plurality of overlapped boxes at the L position are traversed, L=L+1, and after all overlapped boxes are traversed, m=m+1;
Step 5-9: if the D k in the PRI conversion array exceeds the threshold value, searching for a peak value in a continuous area in a D k part exceeding the threshold value, wherein the center of an overlapping box represented by the peak value is the PRI conversion method estimated PRI result.
The PRI overlap bin width is determined by the larger value between the base bin width and the bin center jitter value, base bin width b= (PRI max-PRImin)/K, and the bin center jitter value is determined by the bin center position K L together with the bin jitter rate epsilon i, where the L-th bin center position K L＝(L-1/2)·(PRImax-PRImin)/K+PRImin is the L-th overlap bin width b iL＝max([b,2εikiL constructed at the bin jitter rate epsilon i).
The threshold setting should consider the observation time principle, the subharmonic elimination principle and the noise elimination principle, and the maximum value of the three should be selected for the threshold setting of the overlap box at the L-th position, and then the threshold setting of the overlap box at the L-th position
Wherein α, β, γ is manually set (e.g., α=0.34, β=0.17, γ=3), and is related to the number of overlapping bin dithering rates, and N is the total number of radar pulses in the current environment.
Step 6: and inquiring the sorting results of all modules, finishing the information output of radar signals, such as radar signal types, PRI and the like, and realizing sorting.
Step 6-1: summarizing output information of each module, such as SDIF results aiming at agile radar signal grouping, conventional radar signal SDIF results, spread radar signal spread analysis results, PRI conversion method sorting results and the like;
step 6-2: and outputting the summarized radar signal result, such as radar signal type, PRI and the like.
The complex radar environment is tested on a PC (i 5M 460+6GB RAM,Win7+VS2010) by using the method, ten radar signals and 500 noise points are added, only 30ms is consumed for sorting 5671 pulse points, all signals are successfully sorted, and the parameter estimation error of a large-jitter signal is less than 0.5%, as shown in figure 5.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and variations could be made by those skilled in the art without departing from the technical principles of the present invention, and such modifications and variations should also be regarded as being within the scope of the invention.
In summary, the invention discloses a radar signal sorting method based on combination of an SDIF (serial digital interface) and a PRI (pulse-with-interference) conversion method, which combines the SDIF and the PRI conversion method, improves a pre-sorting algorithm, a sequence searching algorithm, a spread checking flow and the PRI conversion method, improves the performance of the sorting algorithm and improves the sorting speed.
The invention discloses a radar signal sorting method based on combination of an SDIF (serial digital interface) and a PRI (pulse-with-interference) transformation method, which can quickly finish signal sorting in a complex signal environment and has a good sorting effect. The method is characterized by comprising the following steps: the pre-sorting is combined with the main sorting, the SDIF and the PRI conversion method are combined as the main sorting, the SDIF part carries out quick and effective sorting on conventional signals, spread signals and agile signals in the electromagnetic environment of the complex radar, and the PRI conversion method part sorts the rest shaking signals; the carrier frequency pre-sorting design aiming at the frequency agile signal is provided, and the problem of PRI preset sorting range limitation during pre-sorting is solved; optimizing a sequence search algorithm in the SDIF; the speed of the spread inspection process is improved; the multi-stage PRI box structure is designed in the PRI conversion method, so that the PRI estimation accuracy is improved while the improved PRI conversion method keeps the capability of sorting large jitter signals. The method has the advantages of good sorting algorithm performance, quick sorting completion and easy engineering realization.
The invention aims to provide a radar signal sorting method based on combination of an SDIF (serial digital interface) and a PRI (pulse-with-interference) conversion method, which provides a carrier frequency pre-sorting design for a agile signal, solves the problem that the result is limited by a PRI preset sorting range during pre-sorting, optimizes a sequence searching algorithm in the SDIF, ensures that the searching effect is faster and more obvious, improves the speed of a spread inspection process, designs a multi-stage PRI box structure in a modified PRI conversion method, ensures that the improved modified PRI method keeps the capability of sorting large jittering signals, and improves PRI estimation precision.
The purpose of the invention is realized in the following way:
Step 1: setting a long period of observation time and a short period of observation time (such as 1000ms and 10 ms), establishing a histogram of each parameter by using pulse descriptors of radar signals such as parameters of arrival direction DOA, carrier frequency CF, pulse width PW and the like, pre-grouping the radar signals, and distinguishing the frequency agile signals from other radar signals and pre-sorting the radar signals;
Step 2: according to the pre-sorting result of the step 1, an arrival time level difference histogram (initial level difference C is 1) is established for the pre-sorted radar groups by utilizing an SDIF method, and when the peak value of the histogram exceeds a threshold value, the arrival time difference is judged to be a possible radar signal PRI;
Step 3: performing sequence search according to the PRI estimated in the step 2, rapidly searching and extracting radar signals according to the time domain characteristics of a radar signal model, and extracting a complete ragged radar signal at a time;
Step 4: if the searched PRI has the same value, preliminarily considering that a spread signal exists, and restoring a spread signal pulse train according to a time domain sequence to establish a level of a difference histogram to rapidly analyze the spread signal;
Step 5: judging whether complex type radar signals remain in the extracted radar signal electromagnetic space, if so, performing discrete form PRI conversion on the residual pulse sequences in the groups by adopting a multistage PRI box structure (such as 5%,10% and 15%);
step 6: and inquiring the sorting results of all modules, finishing the information output of radar signals, such as radar signal types, PRI and the like, and realizing sorting.
The invention also includes such structural features:
1. the step 1 specifically comprises the following steps:
Step 1-1: noise points are removed. The radar signal parameters such as carrier frequency and pulse width of noise points are randomly distributed, a carrier frequency statistical histogram and a pulse width statistical histogram are respectively established according to tolerance, according to the vertical axis height of the two histograms, a threshold is set to respectively clear isolated noise points and interference points, for example, the tolerance of the carrier frequency statistical histogram is 10MHz, the tolerance of the pulse width statistical histogram is 0.5 mu s, pulse points with the height lower than 10 are used as noise points, points with the height lower than 150 are used as interference points in the pre-sorting aiming at short observation time, points with the height higher than 2000 are used as interference points in the pre-sorting aiming at long observation time, and the points are deleted from pulse description words;
Step 1-2: preliminary pre-sorting is performed by utilizing parameters such as pulse width, arrival angle and the like. And grouping pulse points of similar signals according to parameters such as pulse width, arrival angle and the like by combining tolerance according to the denoised pulse width and arrival angle statistical histogram, and preliminarily diluting the signals. The setting of the tolerance should include the jitter range of the signal pulse width and the arrival angle as far as possible so as to prevent the preliminary pre-selection from causing wrong separation, for example, the pulse width tolerance is set to be 3 mu s, and the arrival angle tolerance is set to be 0.5 degrees;
Step 1-3: the frequency agile signals are distinguished and the other types of signals are pre-sorted. The carrier frequency statistical histogram is utilized in the pre-sorting result of pulse width and arrival angle, a threshold is set to distinguish the frequency agile signals, the signals lower than the threshold are judged to be frequency agile signals, the signals higher than the threshold are divided into other radar signal groups of a plurality of different carrier frequencies according to carrier frequency tolerance, for example, the carrier frequency tolerance is set to be 100MHz, and the threshold is set according to the observation time:
Tthreshold＝βT/τ β∈(0,1)
Wherein T is the observation time, tau is the median value of the current sorting PRI range, two PRI ranges in a short observation time are preset, for example, the PRI range in a short observation time is 0-200 mu s, the PRI range in a long observation time is 200-2000 mu s, and beta is a human set parameter.
2. In the step 2, when the number of peaks exceeding the threshold is not the same, that is, a plurality of PRI values exceed the threshold at the same time, pulse trial search is firstly carried out according to half of the corresponding PRI values, if all search fails, the next-stage difference histogram is directly carried out, and then whether the PRI value exceeds the threshold is detected.
3. The threshold in step 2 is determined by calculation using the following formula:
Tthreshold＝α(E-C)e-λτ
Wherein lambda is the average occurrence probability of radar signals in unit time, E is the number of current pre-grouped total radar pulses, C is the number of ongoing difference stages, (E-C) is the number of pulse intervals, alpha is related to the pulse loss rate, and tau is the total time interval, namely the pulse acquisition time.
4. The step 3 specifically comprises the following steps:
step 3-1: according to the step 2, estimating a level difference histogram corresponding to PRI, searching the pulse number conforming to the PRI in the histogram;
step 3-2: determining a starting pulse position of the estimated PRI within the pulse descriptor;
Step 3-3: performing sequence searching, wherein in the searching process, the pulse position searched at this time is stored, and since the pulse position predicted at the next time is necessary to be after the pulse position searched at this time, the searching is directly started from the stored position at the next time of searching;
Step 3-4: after the search is finished, comparing the number of the pulses extracted in the search with the number of the coincidence PRI found in the level difference histogram, preliminarily judging whether the pulse is a spread signal according to the multiple relation of the pulse number and the PRI, and searching again at the next pulse of the starting pulse if the pulse is the spread signal.
5. The step 4 specifically comprises the following steps:
Step 4-1: according to the PRI estimated value obtained in the step 2, in a certain tolerance, the parameter difference number is primarily judged according to the same PRI value number, and if the tolerance is 1 mu s;
step 4-2: the extracted pulse stream is searched by utilizing the sequence, and the original spread radar signal is restored according to the arrival time sequence;
Step 4-3: sequentially carrying out level one difference on the original spread radar signals, and carrying out histogram statistics;
Step 4-4: according to the parameter, several arrival time differences with higher frequency are sequentially selected as sub-periods.
6. The step 5 specifically comprises the following steps:
Step 5-1: judging whether the pulse number in the space exceeds a threshold (if set to 20) after the current radar signal grouping electromagnetic space is subjected to SDIF separation and extraction, if yes, performing PRI conversion method separation, otherwise, skipping step 5;
step 5-2: respectively creating K overlapped PRI boxes constructed by a plurality of different jitter rates, wherein the jitter rates are epsilon 1、ε2、ε3(ε1<ε2<ε3 in sequence, if K is 300, 300 PRI overlapped boxes of 5%, 10% and 15% are respectively created, and initializing a PRI conversion array, a marking pulse stream array, a time starting point array and a marking time starting point array, wherein the array lengths are K;
step 5-3: let n=2, m=1, τ=t n-tm, judge whether arrival time difference τ is within the preset PRI range, if not, then m=m+1 again judges until m=n-1, if none of the arrival time differences is within the preset PRI range, let n=n+1 continue to carry out PRI range judgment;
Step 5-4: if the arrival time difference tau is within the preset PRI range, traversing each box from the first overlapped box with the jitter rate epsilon 1;
step 5-5: firstly, judging whether an arrival time difference tau is in an overlapped box range constructed by an L-th jitter rate epsilon 1, if so, adding one to an L-th position C L in a mark pulse stream array, judging whether the L-th position of a mark time starting point array is 0, and if not, not processing; if the position is 0, marking the position as a time starting point O k, and marking the corresponding position 1 of the time starting point array;
Step 5-6: the phase value is calculated, and the phase is calculated by using the formula of phase η 0＝(tn-Ok)/τ, wherein when (v=η 0 +0.4999 …) is rounded down to 1 or more than 2 and | (η 0/v)-1|<ζ0) (ζ 0 is a set positive value, such as 0.03), the current t n is taken as the time starting point.
Step 5-7: PRI conversion is carried out, the PRI conversion array D k is updated, and D k＝Dk+exp(2πiη0) is carried out;
Step 5-8: judging whether the arrival time difference tau enters the range of an L-th overlapped box constructed by epsilon 2 dithering rate, then carrying out the steps 5-5, 5-6 and 5-7, judging whether the arrival time difference tau enters the range of an L-th overlapped box constructed by epsilon 3 dithering rate, and the like, wherein after a plurality of overlapped boxes at the L position are traversed, L=L+1, and after all overlapped boxes are traversed, m=m+1;
Step 5-9: if the D k in the PRI conversion array exceeds the threshold value, searching for a peak value in a continuous area in a D k part exceeding the threshold value, wherein the center of an overlapping box represented by the peak value is the PRI conversion method estimated PRI result.
7. The PRI overlap bin width in step 5 is determined by the larger value between the base bin width and the bin center jitter value, base bin width b= (PRI max-PRImin)/K, and the bin center jitter value is determined by the bin center position K L together with the bin jitter rate epsilon i, where the L-th overlap bin width constructed at the bin jitter rate epsilon i is b iL＝max([b,2εikiL at the L-th bin center position K L＝(L-1/2)·(PRImax-PRImin)/K+PRImin.
8. In the step 5, the threshold setting should consider the observation time principle, the subharmonic elimination principle and the noise elimination principle, and the maximum value of the three should be selected for the threshold setting of the overlap box at the L-th position, so that the threshold setting of the overlap box at the L-th position
Wherein α, β, γ is manually set (e.g., α=0.34, β=0.17, γ=3), and is related to the number of overlapping bin dithering rates, and N is the total number of radar pulses in the current environment.
9. The step 6 specifically comprises the following steps:
step 6-1: summarizing output information of each module, such as SDIF results aiming at agile radar signal grouping, conventional radar signal SDIF results, spread radar signal spread analysis results, PRI conversion method sorting results and the like;
step 6-2: and outputting the summarized radar signal result, such as radar signal type, PRI and the like.
Claims (6)
1. The radar signal sorting method based on combination of SDIF and PRI transformation method is characterized by comprising the following steps:
step 1: setting a long period of observation time, a short period of observation time and a short period of observation time, 1000ms and 10ms, and establishing a histogram of each parameter by utilizing parameters of a pulse description word arrival direction DOA, a carrier frequency CF and a pulse width PW of a radar signal to pre-group the radar signal;
step 2: according to the pre-sorting result of the step 1, an arrival time level difference histogram is established for the pre-sorted radar groups by utilizing an SDIF method, the initial level difference C is 1, and when the peak value of the histogram exceeds a threshold value, the arrival time difference is judged to be a possible radar signal PRI;
Step 3: performing sequence search according to the PRI estimated in the step 2, rapidly searching and extracting radar signals according to the time domain characteristics of a radar signal model, and extracting a complete ragged radar signal at a time;
Step 4: if the searched PRI has the same value, preliminarily considering that a spread signal exists, and restoring a spread signal pulse train according to a time domain sequence to establish a level of a difference histogram to rapidly analyze the spread signal;
Step 5: judging whether complex type radar signals remain in the extracted radar signal electromagnetic space; if the pulse sequence exists, carrying out discrete form PRI conversion on the residual pulse sequence in the packet by adopting a multi-stage PRI box structure, wherein the specific steps are as follows:
Step 5.1: respectively creating K overlapped PRI boxes constructed by a plurality of different jitter rates epsilon i, initializing a PRI conversion array, a marking pulse stream array, a time starting point array and a marking time starting point array, wherein the array lengths are K;
Step 5.2: let n=2, m=1, τ=t n-tm, determine if the arrival time difference τ is within a preset PRI range;
If the arrival time difference tau is not within the set PRI range, making m=m+1 to judge again until m=n-1; if the arrival time difference tau is still not within the preset PRI range until m=n-1, making n=n+1, and continuing to judge the PRI range;
If the arrival time difference τ is within the preset PRI range, starting from the first overlapped PRI box with jitter rate epsilon 1, traversing each box, and specifically, the steps are as follows:
step 5.2.1: judging whether the arrival time difference tau is in an overlapped PRI box range constructed by using epsilon 1 as a jitter rate or not;
If yes, adding one to the L position C L in the marking pulse stream array, judging whether the L position of the marking time starting point array is 0, and if not, not processing; if the position is 0, marking the position as a time starting point O k, and marking the corresponding position of the time starting point array as 1;
Step 5.2.2: calculating a phase value eta 0,η0＝(tn-Ok)/tau; when the condition that v is rounded down to 1 is met, or when v is more than 2 and | (eta 0/v)-1|≤ζ0 is met, the current t n is taken as a time starting point, wherein v=eta 0+0.4999;ζ0 is a set positive value;
Step 5.2.3: PRI conversion is carried out, the PRI conversion array D k is updated, and D k＝Dk+exp(2πjη0 is caused to be carried out);
Step 5.2.4: judging whether the arrival time difference tau enters the range of an L-th overlapped PRI box constructed by epsilon 2 jitter rate, then carrying out the steps 5.2.1, 5.2.2 and 5.2.3, judging whether the arrival time difference tau enters the range of an L-th overlapped PRI box constructed by epsilon 3 jitter rate, and the like, wherein after traversing a plurality of overlapped PRI boxes at the L position, L=L+1 is caused, and after traversing all overlapped PRI boxes, m=m+1 is caused;
Step 5.3: if the D k in the PRI conversion array exceeds the threshold value, searching for a peak value in a continuous area in a D k part exceeding the threshold value, wherein the center of an overlapped PRI box represented by the peak value is the PRI conversion method estimated PRI result;
Step 6: and inquiring the sorting result of each module, finishing the information output of the radar signals, and realizing sorting.
2. The radar signal sorting method based on combination of an SDIF and a PRI transform method according to claim 1, wherein step 1 specifically includes: removing noise points; preliminary pre-sorting by utilizing pulse width and arrival angle parameters; the frequency agile signals are distinguished and the other types of signals are pre-sorted.
3. The radar signal sorting method based on combination of SDIF and PRI conversion method according to claim 1, wherein in step 2, when the number of peaks exceeding a threshold is not uniform, i.e. a plurality of PRIs exceed the threshold at the same time, pulse trial search is performed according to half of the corresponding PRIs, if both search fails, next-stage difference value histogram is directly performed, and then whether PRI values exceed the threshold is detected.
4. The radar signal sorting method based on combination of SDIF and PRI transform method according to claim 1, wherein the threshold in step 2 is determined by calculation using the following formula:
Tthreshold＝α(E-C)e-λτ
Wherein lambda is the average occurrence probability of radar signals in unit time, E is the number of current pre-grouped total radar pulses, C is the number of ongoing difference stages, (E-C) is the number of pulse intervals, alpha is related to the pulse loss rate, and tau is the total time interval, namely the pulse acquisition time.
5. The method of claim 1, wherein the overlapping PRI bin width in step 5 is determined by a larger value between a base bin width and a bin center jitter value, base bin width b= (PRI max-PRImin)/K, and the bin center jitter value is determined by a bin center position K L and a bin jitter rate epsilon i, wherein an L-th bin center position K L＝(L-1/2)·(PRImax-PRImin)/K+PRImin is the L-th overlapping bin width b iL＝max([b,2εikiL constructed with a bin jitter rate epsilon i.
6. The radar signal sorting method based on the combination of the SDIF and the PRI transform method according to claim 1, wherein in step 5.3, the threshold setting should consider the observation time principle, the subharmonic elimination principle and the noise elimination principle, and the threshold setting for the overlapped PRI box should select the maximum value of the three, then the L-th overlapped PRI threshold is set as follows: Wherein alpha, beta, gamma are constant parameters and are related to the number of the dithering rates of the overlapping boxes; n is the total number of radar pulses in the current environment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910976041.7A CN110764063B (en) | 2019-10-15 | 2019-10-15 | Radar signal sorting method based on combination of SDIF and PRI transformation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910976041.7A CN110764063B (en) | 2019-10-15 | 2019-10-15 | Radar signal sorting method based on combination of SDIF and PRI transformation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110764063A CN110764063A (en) | 2020-02-07 |
| CN110764063B true CN110764063B (en) | 2024-04-30 |
Family
ID=69331246
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910976041.7A Active CN110764063B (en) | 2019-10-15 | 2019-10-15 | Radar signal sorting method based on combination of SDIF and PRI transformation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110764063B (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111257839B (en) * | 2020-03-30 | 2021-12-21 | 吉林大学 | Radar signal sorting method |
| CN111722188B (en) * | 2020-05-18 | 2024-03-15 | 中国人民解放军63892部队 | PRI conversion radar signal sorting method based on STFT pre-sorting |
| CN111781564B (en) * | 2020-06-12 | 2022-11-18 | 中国船舶重工集团公司第七二四研究所 | Rapid prejudging method for jitter signal pulse sequence |
| CN111693945B (en) * | 2020-06-19 | 2023-05-09 | 清华大学 | Inter-pulse modulation method, inter-pulse modulation system, computer device, and storage medium |
| CN111708020B (en) * | 2020-07-14 | 2023-08-04 | 南京理工大学 | Radar signal sorting tracking method and system based on anti-radiation seeker |
| CN112036074B (en) * | 2020-07-27 | 2024-04-02 | 西安电子科技大学 | Radar signal sorting method and system in high pulse density environment |
| CN112068089B (en) * | 2020-08-13 | 2023-07-21 | 中国人民解放军海军工程大学 | Sequence retrieval method based on particle filtering |
| CN112198481B (en) * | 2020-10-09 | 2023-07-21 | 哈尔滨工程大学 | PRI jitter radar signal sorting method under condition of pulse loss aliasing |
| CN112379337A (en) * | 2020-10-13 | 2021-02-19 | 北京信息科技大学 | Short-distance false alarm eliminating method for long-short pulse combined pulse compression radar |
| CN112637134A (en) * | 2020-12-02 | 2021-04-09 | 电子科技大学 | Signal sorting method for time hopping signals of data link communication system |
| CN112698274A (en) * | 2020-12-05 | 2021-04-23 | 扬州宇安电子科技有限公司 | Radar signal sorting and pulse sequence extraction system based on hierarchical PRI transformation |
| CN112763989B (en) * | 2020-12-30 | 2024-02-06 | 湖南艾科诺维科技有限公司 | CDIF-based jitter signal sorting method |
| CN112986928B (en) * | 2021-03-11 | 2022-06-17 | 哈尔滨工程大学 | Signal sorting multi-source fusion processing method in complex electromagnetic environment |
| CN113156391B (en) * | 2021-04-25 | 2022-08-05 | 电子科技大学 | Radar signal multi-dimensional feature intelligent sorting method |
| CN113702920B (en) * | 2021-08-25 | 2023-07-11 | 西南交通大学 | Combined complexity value calculation method for distinguishing radar data with different pulse spread |
| CN113721219B (en) * | 2021-10-08 | 2023-07-04 | 中国电子科技集团公司第三十八研究所 | Radar signal sorting method and system based on multi-parameter clustering |
| CN114660560B (en) * | 2022-03-11 | 2022-12-06 | 中国人民解放军战略支援部队信息工程大学 | Pulse repetition interval sorting method based on equivalent DTOA density curve |
| CN117491953B (en) * | 2024-01-02 | 2024-03-26 | 南京航天工业科技有限公司 | Radar signal sorting method based on linked list |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5565764A (en) * | 1995-05-05 | 1996-10-15 | Texas Instruments Incorporated | Digital processing method for parameter estimation of synchronous, asynchronous, coherent or non-coherent signals |
| CN106842149A (en) * | 2017-03-31 | 2017-06-13 | 中国科学院电子学研究所 | With the improved sequential difference histogram method for separating of Clustering |
| CN108181613A (en) * | 2017-12-04 | 2018-06-19 | 山东航天电子技术研究所 | A kind of PRI dither signals sequence difference non-uniform quantizing method for separating |
-
2019
- 2019-10-15 CN CN201910976041.7A patent/CN110764063B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5565764A (en) * | 1995-05-05 | 1996-10-15 | Texas Instruments Incorporated | Digital processing method for parameter estimation of synchronous, asynchronous, coherent or non-coherent signals |
| CN106842149A (en) * | 2017-03-31 | 2017-06-13 | 中国科学院电子学研究所 | With the improved sequential difference histogram method for separating of Clustering |
| CN108181613A (en) * | 2017-12-04 | 2018-06-19 | 山东航天电子技术研究所 | A kind of PRI dither signals sequence difference non-uniform quantizing method for separating |
Non-Patent Citations (5)
| Title |
|---|
| Wei Hua Xiao等.An Improved SDIF Radar Pulse Signal Main Sorting Algorithm.《Advanced Materials Research》.2013,全文. * |
| Yanchao Liu等.Improved method for deinterleaving radar signals and estimating PRI values.《IET RADAR SONAR AND NAVIGATION》.2018,全文. * |
| 刘明.一种改进的基于PRI参数的雷达信号分选算法.《舰船电子工程》.2018,全文. * |
| 安琦等.基于改进SDIF算法的雷达脉冲信号分选技术研究.《火力与指挥控制》.2018,全文. * |
| 张保群.一种抗SDIF分选的脉冲重复间隔参差设计方法.《兵器装备工程学报》.2016,全文. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110764063A (en) | 2020-02-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110764063B (en) | Radar signal sorting method based on combination of SDIF and PRI transformation method | |
| CN112036074B (en) | Radar signal sorting method and system in high pulse density environment | |
| Milojević et al. | Improved algorithm for the deinterleaving of radar pulses | |
| CN109270497B (en) | Multidimensional parameter pre-sorting method for radar pulse signals | |
| CN112986928B (en) | Signal sorting multi-source fusion processing method in complex electromagnetic environment | |
| CN104198999B (en) | A kind of pulse deinterleaving method based on isomorphism sequence | |
| CN109031215B (en) | Method for estimating pulse repetition period of staggered radar under high pulse loss | |
| CN114019505A (en) | Radar signal sorting method and system based on PRI interval information | |
| CN112528774B (en) | Intelligent unknown radar signal sorting system and method in complex electromagnetic environment | |
| CN114089285B (en) | Signal sorting method based on first-order Pulse Repetition Interval (PRI) | |
| CN111104398A (en) | Detection method and elimination method for approximate repeated record of intelligent ship | |
| US7760135B2 (en) | Robust pulse deinterleaving | |
| CN101604394A (en) | Increment study classification method under a kind of limited storage resources | |
| CN102521534A (en) | Intrusion detection method based on crude entropy property reduction | |
| CN108549055A (en) | A kind of method for separating of same orientation multi-section homotype or different shaped radar signal | |
| CN112198481B (en) | PRI jitter radar signal sorting method under condition of pulse loss aliasing | |
| CN112698274A (en) | Radar signal sorting and pulse sequence extraction system based on hierarchical PRI transformation | |
| CN107133321B (en) | Method and device for analyzing search characteristics of page | |
| CN110263625A (en) | A kind of envelope extraction algorithm of signal pulse amplitude sorting | |
| Liu et al. | A radar signal sorting algorithm based on PRI | |
| CN111257839B (en) | Radar signal sorting method | |
| CN114185785A (en) | Natural language processing model test case reduction method for deep neural network | |
| CN114660560B (en) | Pulse repetition interval sorting method based on equivalent DTOA density curve | |
| CN107016354B (en) | Method and system for extracting characteristic pattern of aluminum electrolysis anode current sequence | |
| Govalkar et al. | Siamese Network based Pulse and Signal Attribute Identification |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant |