KR101300649B1 - A method of extracting jitter pri pulsetrain of radar signal using adaptive histogram, and a apparatus of extracting jitter pri pulsetrain of radar signal using the same - Google Patents

Abstract

PURPOSE: A method and a device for extracting a radar signal jitter pulse repetition interval (PRI) pulse train using an adaptive histogram are provided to improve the detection accuracy of a radar signal in a high density multiple signal environment and to be applied to various electronic warfare systems necessary to be analyzed in signals. CONSTITUTION: A signal receiving part (10) comprises an antenna for sensing a radar signal. The signal receiving part processes the signal detected by the antenna and transmits the signal to a control part (20). The control part is classified into a histogram generation module (22), a candidate list setting module (24), a histogram extension module (25), an extraction threshold comparing module (26), and a jitter PRI pulse train extraction module (28). The histogram generation module generates a histogram using the difference between a set disparity and the time of arrival (TOA). The candidate list setting module selects a Bin which exceeds a pre-set candidate threshold among a histogram Bin and sets the Bin as a candidate list. The histogram extension module merges the histogram Bin in order to choose PRI for extraction using the candidate list. The extraction threshold comparing module compares the stored candidate list with the extracted threshold to determine whether to extract or not. The jitter PRI pulse train extraction module restarts the control operation by confirming the number of pulses remained after the extraction is greater than the jitter PRI pulse train accreditation number and increasing degree. [Reference numerals] (10) Receiving unit; (20) Control unit; (22) Histogram generation module; (24) Candidate list setting module; (25) Histogram expansion module; (26) Extraction threshold comparing module; (28) Jitter PRI pulse train extraction module

Description

A method of extracting jitter PRI pulsetrain of radar signal using adaptive histogram, and a apparatus of extracting jitter PRI pulsetrain of radar signal using the same}

The present invention relates to a radar signal jitter pulse repetition interval (PRI) pulse train extraction method, and more particularly, radar signal jitter pulse repetition interval (PRI) pulse train extraction applied to the detection of radar signals in an electronic warfare support (Electronic warfare support) system. The present invention relates to a radar signal jitter PRI pulse train extraction apparatus using the same.

Electronic warfare support systems, after receiving enemy signals, identify and locate threat emitters to help determine enemy power structures and placement.

The main functions of the electronic warfare support system are the detection of threat source, the type and operation of the threat, the location of the threat source, and the display of threat information to support the situation awareness.

The electronic warfare support system measures the pulse characteristics of the received signal, identifies the rules, correlations, continuity, etc. of pulse trains from the collected data, analyzes the characteristics of the data, and emits the source identification data. Check the signal source by comparing with.

In order to detect radar signals in an electronic warfare support system, pulse train separation for each signal source must be preceded in a mixed signal environment of high density multiple radar signals.

Pulse string separation of the radar signal may be performed through pulse repetition interval (PRI) estimation. The PRI considered in pulse train extraction can be largely classified into fixed PRI and jitter PRI.

Among them, a method of separating a radar signal pulse train including jitter PRI pulse train extraction includes a histogram method, a Fourier transform method, and a wavelet transform method.

In the method using a histogram, a histogram is generated using a difference of time of arrival (TOA) between pulses, and a pulse train is separated by estimating PRI of a pulse train using a peak value of the histogram.

However, this method does not provide a detailed method for jitter PRI pulse train extraction. Therefore, the method has a disadvantage in that reliability and accuracy cannot be guaranteed by relying on manual analysis of the operator.

The method using the Fourier transform has advantages in that the PRI estimation accuracy is high, the processing speed is high, and the estimation ability for the jitter PRI signal is superior to the histogram method.

However, this method requires a sufficient number of pulses as inputs for proper frequency resolution and has the disadvantage of being vulnerable to missing pulses. In addition, when only a single signal exists, it is impossible to estimate the PRI, and in a high-density signal environment, the processing speed drops sharply.

The method using wavelet transform is robust against missing and unnecessary pulses, has high PRI estimation accuracy, and obtains time information when a signal exists on the time axis and the number of pulse trains included in the received pulse train. It is possible to detect the signal.

However, this method has a disadvantage in that it is not suitable for an electronic warfare system that requires real-time processing of radar threat in a high density signal environment because the processing speed increases rapidly as the number of input pulses increases.

KR 10-2010-0121108A, November 17, 2010, Fig. 1

SUMMARY OF THE INVENTION An object of the present invention is to provide a radar signal jitter PRI pulse train extraction method using an adaptive histogram which is simple to implement in a high density multi-signal environment and can be used in a real-time system, and a radar signal jitter PRI pulse train extraction device using the same. .

One aspect of the present invention for achieving the above object relates to a radar signal jitter pulse repetition interval (PRI) pulse train extraction method applied to the detection of the radar signal of the electronic warfare support (Electronic warfare support) system, the radar signal jitter PRI pulse train The extraction method includes (a) initializing the size and range of the histogram bin; (b) generating a histogram using a diff, which is an index interval of the TOA set by the time of arrival information of the received pulse train; (c) selecting bins of histograms exceeding a candidate threshold value among bins of the generated histograms and setting them as candidate lists; And (d) extracting the jitter PRI pulse train using the set candidate list.

The histogram generated in the step (b) may be generated by accumulating on the previously generated histogram when a previously generated histogram exists.

When setting of the candidate list is completed in step (c), the candidate list may be sorted in ascending order of the cumulative value of the histogram generated by the accumulation.

The step (d) may include: (d1) merging the histogram bins of the candidate list to extract the jitter PRI pulse train using the set candidate list; (d2) when merging of histogram bins of the candidate list is completed, storing a change range calculated by multiplying the merged range of histogram bins by the number of merged histogram bins and a cumulative number of histograms; (d3) comparing the candidate list with an extraction threshold to determine whether to extract the jitter PRI pulse train and storing extraction target information corresponding to the determination result in the candidate list; And (d4) extracting the jitter PRI pulse string using the extraction target candidate when it is determined that the extraction target candidate exists through the extraction target information stored in the candidate list.

In step (d), if it is determined that the extraction target candidate does not exist based on the extraction target information stored in the candidate list, the order (diff) is increased to increase the order (d). The method may further include performing a control procedure.

Merging of the histogram bins of the candidate list in step (d1) may be performed when the conditions of the continuous missing allowable threshold value (θms), the change range threshold value (θva) and the cumulative number threshold value (θct) are satisfied.

The extraction threshold θ _ex of step (d3) may be expressed by Equation 1.

, t = TOA, b_idx= 상기 후보리스트의 히스토그램 Bin의 번호, b_S = 상기 후보리스트의 히스토그램 Bin의 크기,

= 0.7~1.3Equation 1:

t = TOA, b _idx = number of histogram bins of the candidate list, b _S = size of histogram bins of the candidate list,

= 0.7 to 1.3

In step (d3), the candidate to be extracted is selected and the PRI _mean is calculated using the changed range of the selected candidate to be extracted, and the calculated PRI _mean and the variation range δ are calculated. Extracting the jitter PRI pulse train by satisfying a jitter change range (PRI _mean + δ), and extracting the jitter PRI pulse train recognizes a jitter PRI pulse train in which the total number of pulses of the selected candidate to be extracted is preset. If more than the number can be performed.

In the step (d), after the extraction of the jitter PRI pulse train, if the number of remaining pulses is equal to or greater than the number of recognized jitter PRI pulse trains, the order (diff) is increased to control from the steps (a) to (d). The method may further include terminating the extraction of the jitter PRI pulse string when the number of remaining pulses is smaller than the number of recognized jitter PRI pulse strings.

Another aspect of the present invention for achieving the above object relates to a radar signal jitter pulse repetition interval (PRI) pulse train extraction apparatus applied to the detection of the radar signal of the electronic warfare support (Electronic warfare support) system, the radar signal jitter The PRI pulse string extracting apparatus includes: a signal receiving unit configured to detect and process an external radar signal; And a controller for performing the jitter PRI pulse train extraction method according to the above-described embodiment based on the information detected and processed by the signal receiver.

As described above, the present invention generates candidate lists through adaptive histograms from the entire pulse trains collected, obtains a precise average PRI and jitter change range through histogram expansion, and extracts jitter PRI pulse trains based on the radar in a high density multi-signal environment. It can be applied to various electronic warfare systems that require high signal detection accuracy and signal analysis.

1 is a flowchart illustrating a radar signal jitter PRI pulse train extraction method according to an embodiment of the present invention.
2 is a graph for explaining the concept of degree in the pulse train of the radar signal.
3 is a flowchart illustrating a radar signal jitter PRI pulse train extraction apparatus according to another embodiment of the present invention.

Hereinafter, a radar source jitter PRI pulse train extraction method and a radar signal jitter PRI pulse train extraction method using the same will be described with reference to the accompanying drawings.

1 is a flowchart illustrating a method of extracting a radar signal jitter PRI pulse train according to an embodiment of the present invention.

Referring to FIG. 1, the method of extracting a radar signal jitter PRI pulse train according to the present embodiment includes initializing a histogram 110, accumulating and generating a histogram corresponding to a specific order 120, and generating a jitter PRI candidate list. Extracting step 130, expanding the histogram 140, comparing the expanded result with the extraction threshold (θext) 150, checking whether the extraction target pulse train is present (160), jitter The method may include extracting the PRI pulse string 170, determining the remaining pulses to determine whether to repeat the pulse string extraction 180, and terminating the jitter PRI pulse string extraction 190.

The histogram initialization step S110 is a step of setting an initial value (histogram bin size, histogram range, or number of histogram bins) for generating a histogram.

The histogram generating step S120 sets a diff using the TOA (Time Of Arrival) information of the pulse string received by the signal receiving unit, and generates a histogram using the set diff, that is, the difference between TOAs. .

The order (diff) refers to the interval of the TOA index for generating the histogram, and the concept of the order will be described with reference to FIG. 2. 2 is a graph for explaining the concept of degree in the pulse train of the radar signal. That is, the interval between TOA [0] and TOA [1] is primary (diff = 1), and the interval between TOA [0] and TOA [2] is secondary (diff = 2).

Since the histogram in the present embodiment uses a cumulative histogram, if a histogram previously generated when the histogram is generated, the histogram is accumulated and additionally generated.

In the candidate list setting step S130, bins exceeding a preset candidate threshold value? Cd from among histogram bins are selected and set as candidate lists. When the candidate list setting is completed, the candidate list is sorted in ascending order.

Histogram expansion step (S140), extraction threshold value comparison step (S150), extraction target pulse train check step (S160), jitter PRI pulse train extraction step 170, residual pulse check step (S180) and jitter PRI pulse train extraction end described later Steps S190 are control steps of extracting the jitter PRI pulse train using the candidate list set in the candidate list setting step of step S130.

The histogram expansion step S140 merges the histogram bins of the candidate list in order to select a PRI to be extracted using the candidate list. Repeat the process of selecting candidates one by one from the candidate list and merging the bins one by one from the histogram bin.

The end of the histogram bin merging determines whether the merging of the histogram bin is terminated by comparing with the preset consecutive missing allowable threshold value (θms), the change range threshold value (θva), and the cumulative number threshold value (θct).

 If it is determined that the merging of the histogram bins is completed, the merge range and the cumulative number information of the candidate bins are added to the candidate list and stored. The size of the histogram bin is multiplied by the number of merged bins and stored as a change range. That is, the candidate list includes information as shown in Equation (1).

[Equation 1]

Candidate list = {number of candidate bins, change range, cumulative number, whether to extract}

In the extraction threshold comparison step (S150), the extraction target included in the candidate list is determined by comparing the candidate list with the extraction threshold value θ _ex .

는 펄스 누락과 누적 히스토그램의 특성을 고려하여 0.7~1.3 사이의 값으로 결정된다.Extraction threshold, θ _ex is set as in Equation 2, t is TOA, b _idx is the number of candidate Bin, b _S is the size of the bin,

Is determined to be between 0.7 and 1.3, taking into account the missing pulse and cumulative histogram.

When the determination of the extraction target is finished, the extraction target in the candidate list is set to a value of 0 (excluding extraction target) or 1 (including extraction target).

&Quot; (2) "

The extraction target pulse string checking step (S160) is a step of checking whether there is an extraction target of 1 in the candidate list of which extraction target is determined in step S150. If the extraction target candidate does not exist, the order is increased. It starts again from the histogram generation step of step S120.

In the jitter PRI pulse string extraction step (S170), a candidate having an extraction target of 1 is selected from a candidate list, a PRI _mean is calculated using a change range of the selected candidate, and a pulse string extraction including a change range δ is performed. Do this.

Pulse train extraction selects pulses satisfying the jitter change range (PRI _mean + δ) one by one, and if the total number of selected pulses is more than the number of jitter PRI pulse train recognition (θ _JPT ) It consists of a pulse train. The candidate is selected from the candidate list until the jitter PRI pulse train configuration is performed.

The remaining pulse checking step 180 checks whether the number of remaining pulses after extraction is equal to or greater than the number of jitter PRI pulse trains recognized (θ _JPT ) and if the number of remaining pulses is greater than or equal to θ _JPT , increases the order to generate a histogram that is S120. Start again.

If it is determined in step S180 that the number of remaining pulses is not greater than or _equal to θ _{JPT, the} jitter PRI pulse string extraction end step (S190) ends the control procedure of the method for extracting the jitter PRI pulse string according to the present embodiment.

The extracted jitter PRI pulse train extracted by the radar signal jitter PRI pulse train extraction method according to the present embodiment may be expressed by Equation 3 below.

&Quot; (3) "

Extracted jitterPRI pulse train = {average PRI, jitter change range, index of extracted pulses}

Hereinafter, an apparatus for extracting a jitter PRI pulse train according to an embodiment of the present invention will be described with reference to FIG. 3. 3 is a functional block diagram of an apparatus for extracting jitter PRI pulse trains according to an exemplary embodiment of the present invention.

The jitter PRI pulse train extracting apparatus 1 according to the present embodiment is a device applied to a radar signal detecting apparatus for detecting and identifying a radar signal, and is operated using the radar signal jitter PRI pulse train extracting method according to the above-described embodiment. Can be.

As shown in FIG. 3, the radar signal jitter PRI pulse train extracting apparatus 1 according to the present embodiment includes a signal receiver 10 for detecting a radar signal and a controller 20 for performing the above-described method of extracting the jitter PRI pulse train. ) May be included.

The signal receiver 10 includes an antenna for detecting a radar signal, and a plurality of antennas may be provided. The signal receiver 10 processes the signal detected through the antenna and transmits the signal to the controller 20.

When the radar signal is detected, the signal receiver 10 may measure a carrier frequency, a pulse width, a pulse amplitude, a time of arrival, and the like of the signal.

The control unit 20 is functionally histogram generation module 22, candidate list setting module 24, histogram expansion module 25, extraction threshold comparison module as shown in Figure 3 to implement the signal source position estimation method described above 26 and the jitter PRI pulse train extraction module 28.

The histogram generation module 22 sets an initial value (histogram bin size, histogram range, or number of bins) for histogram generation, and uses TOA (Time Of Arrival) information transmitted from the signal receiver 10 to FIG. 2. Set the diff as shown in. The histogram generating module 22 generates a histogram by using the difference between the set order diff and the TOA.

The candidate list setting module 24 selects bins exceeding the preset candidate threshold value? Cd from the histogram bins and sets them as candidate lists. When selection of the candidate list is completed, the candidate list is sorted in ascending order of accumulation value.

The histogram expansion module 25 merges the histogram bins to select the PRI to be extracted using the candidate list. The histogram expansion module 25 may expand the histogram by selecting candidates from the candidate list one by one and repeating merging bins from the corresponding bins one by one.

The end of the histogram bin merging is determined by comparison with a preset continuous missing allowable threshold value (θms), a change range threshold value (θva), and a cumulative number threshold value (θct).

When the histogram expansion is completed, the histogram expansion module 25 adds and stores the merge range and the cumulative number information of bins in the candidate list. The merge range of bins is stored as a change range by multiplying the size of the bin by the number of merged bins. The candidate list whose extension has been completed includes information such as Equation 1 described above.

The extraction threshold value comparison module 26 determines whether to be extracted by comparing the candidate list stored by the histogram extension module 25 with the extraction threshold value θ _ex expressed by Equation 2 described above.

If the extraction target candidate does not exist in the candidate list in which the extraction target is determined, the extraction threshold comparison module 26 increases the degree and restarts the control operation from the histogram generating module 22.

When there is a candidate to be extracted from the candidate list, the jitter PRI pulse train extraction module 28 selects a candidate from the candidate list and extracts a pulse train using a change range of the selected candidate.

Pulse train extraction is performed by selecting pulses satisfying the value of jitter change range (PRI _mean + δ) from the pulse trains one by one, and if the total number of selected pulses is more than the number of jitter PRI pulse train recognition number (θ _JPT ) It consists of a jitter PRI pulse train. The candidate list is selected until the jitter PRI pulse train configuration is performed.

The jitter PRI pulse train extraction module 28 checks whether the number of remaining pulses after extraction is _{equal to} or greater than the number of jitter PRI pulse train recognition (θ _JPT) and the number of remaining pulses is the number of pulse train recognition. If it is determined to be abnormal, the order is increased to restart the control operation from the histogram generating module 22.

On the other hand, the jitter PRI pulse train extraction module 28 ends the control operation for the extraction of the jitter PRI pulse train performed by the control unit 20 when it is determined that the number of remaining pulses is not more than the number of pulse train recognition number (θ _JPT) .

The extracted jitter PRI pulse train extracted by the control of the controller 20 may be expressed as in Equation 3 described above.

As described above, the method for extracting jitter PRI pulse trains and the apparatus for extracting jitter PRI pulse trains generate candidate lists through adaptive histograms in all pulse trains collected in a high-density multi-signal environment. By obtaining the accurate average PRI and jitter change range and extracting the jitter PRI pulse train based on it, the implementation is simple, the time complexity is low, and the extraction accuracy of the jitter PRI pulse pulse stream can be improved.

In addition, the jitter PRI pulse train extraction method and the jitter PRI pulse train extraction apparatus using the same according to an embodiment of the present invention can be directly applied to the electronic warfare support (Electronic warfare Support) system and ELINT (Electronic Intelligence) system that requires signal analysis.

1: Radar Signal Jitter Pri Pulse Pulse Extractor
10: signal receiver
20: control unit
22: Histogram Generation Module
24: candidate list setting module
25: histogram extension module
26: extraction threshold comparison module
28: Jitter Pri Pulse Pulse Extraction Module

Claims (10)

In the radar signal jitter pulse repetition interval (PRI) pulse train extraction method applied to the detection of the radar signal of the electronic warfare support system,
(a) initializing the size and range of the histogram bin;
(b) generating a histogram using a diff, which is an index interval of the TOA set by the time of arrival information of the received pulse train;
(c) selecting bins of histograms exceeding a candidate threshold value among bins of the generated histograms and setting them as candidate lists; And
(d) extracting the jitter PRI pulse train using the set candidate list. The method of claim 1,
The histogram generated in the step (b) is, if there is a previously generated histogram is generated by accumulating on the previously generated histogram, radar signal jitter PRI pulse string extraction method. The method of claim 2,
If the setting of the candidate list is completed in the step (c), the candidate list is radar signal jitter PRI pulse string extraction method, characterized in that the cumulative value of the accumulated histogram is arranged in ascending order. The method of claim 1, wherein step (d)
(d1) merging histogram bins of the candidate list to extract jitter PRI pulse trains using the set candidate list;
(d2) when merging of histogram bins of the candidate list is completed, storing a change range calculated by multiplying the merged range of histogram bins by the number of merged histogram bins and a cumulative number of histograms;
(d3) comparing the candidate list with an extraction threshold to determine whether to extract the jitter PRI pulse train and storing extraction target information corresponding to the determination result in the candidate list; And
(d4) extracting the jitter PRI pulse train using the candidate candidate for extraction if it is determined that the candidate for extraction is present through the extraction target information stored in the candidate list; Pulse train extraction method. The method of claim 4, wherein step (d)
If it is determined that the extraction target candidate does not exist through the extraction target information stored in the candidate list, the step of increasing the order (diff) to perform the control procedure from the steps (a) to (c) The radar signal jitter PRI pulse train extraction method further comprising. The method of claim 4, wherein
The merging of the histogram bins of the candidate list in step (d1) is performed when the conditions of the continuous missing allowable threshold value (θms), the change range threshold value (θva) and the cumulative number threshold value (θct) are satisfied. JitterPRI pulse train extraction method. The method of claim 4, wherein
The extraction threshold value θ _ex of the step (d3) is expressed by Equation 1 radar signal jitter PRI pulse train extraction method.
Equation 1:

, t = TOA, b _idx = number of histogram bins of the candidate list, b _S = Size of histogram bin of the candidate list,

= 0.7 to 1.3 The method of claim 4, wherein step (d3),
Selecting the candidate to be extracted and calculating a PRI _mean using the changed range of the selected candidate to be extracted, the jitter change range including the calculated PRI _mean and the variation range δ Extracting the jitter PRI pulse string by satisfying (PRI _mean + δ), and extracting the jitter PRI pulse string is performed when the total number of pulses of the selected candidate to be extracted is equal to or greater than a predetermined number of recognized jitter PRI pulse strings. Radar signal jitter PRI pulse train extraction method. The method of claim 8, wherein step (d)
After extraction of the jitter PRI pulse train, if the number of remaining pulses is greater than or equal to the number of jitter PRI pulse trains, the order (diff) is increased to perform the control procedure from step (a) to step (d), and the remaining And if the number of pulses is smaller than the number of recognized jitter PRI pulse strings, terminating the extraction of the jitter PRI pulse strings. In the radar signal jitter pulse repetition interval (PRI) pulse train extraction apparatus applied to the detection of the radar signal of the electronic warfare support system,
A signal receiver for detecting and processing an external radar signal; And
A radar signal jitter PRI pulse train extraction comprising a control unit for performing the jitter PRI pulse train extraction method according to any one of claims 1 to 9 based on the information detected and processed by the signal receiver. Device.

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