KR101968141B1 - Environmental adaptation auto threshold setting type radar apparatus and control method thereof - Google Patents

Abstract

The present invention relates to an environment adaptive automatic threshold value setting radar apparatus and a control method thereof, and a method of controlling the environment adaptive automatic threshold value setting radar apparatus and a control method thereof, wherein the method comprises the steps of: generating a first radar signal having a first range bin, Generating a second signal corresponding to a temporal change amount of a second radar signal in a frequency rising period having a first signal and a first range bin, generating a first signal filtered by the first low- Generating a third signal by using a second filtered signal obtained by low-pass-filtering the radar signal, and generating a third signal by using a first signal, a second signal, a third signal, and a third range signal of a third radar signal in a frequency- A fourth signal corresponding to a temporal change amount and a fifth signal corresponding to a temporal change amount of a fourth radar signal in a frequency rising period having a second range bin are combined in a predetermined method, Generating a sixth signal amplifying the call component, using the third signal to obtain an automatic limit value in the first range bin, and detecting an intrusion based on the sixth signal and the automatic limit value do. According to the present invention, there is an advantage that the threshold value can be calculated and applied automatically by analyzing the change amount of the environmental noise.

Description

TECHNICAL FIELD [0001] The present invention relates to an automatic adaptive threshold value setting radar apparatus,

The present invention relates to a radar apparatus and a control method thereof, and more particularly, to a radar apparatus having an environment adaptive automatic limit value setting function and a control method thereof.

A radar can be used when it is difficult to visually detect or locate an object due to bad weather or cover. Typically, a radar emits an electromagnetic wave having a wavelength of microns, and when the radiated electromagnetic wave is reflected by the object, it receives the reflected electromagnetic wave to detect the object and locate the object.

One type of radar is the continuous wave radar. Continuous wave radars can continuously transmit signals and receive echoes continuously. A frequency modulation continuous wave (FMCW) radar in a continuous wave radar provides a specific indication on a continuously transmitted signal and can obtain distance information to an object by dividing an echo by a display.

In the existing 24GHz Industrial Scientific and Medical (ISM) band fence type radar and other radar, it is judged whether the intruder is based on the threshold value based on SNR (Signal-Noise Ratio) Respectively.

Since it is difficult to apply the same limit value according to the environment change, the initial setting process is required according to the changing environment. In other words, the sensitivity is set by the distance test in order to confirm the change of the detection performance caused by the deviation of the radar component and securing the detection performance in various installation environments. As shown in FIG. 9, the existing distance-based test method checks the presence or absence of an alarm in the sensing area by adjusting the sensitivity by + or -1. This is the process of reapplying the limit value based on the existing ideal experimental data.

However, in the conventional method of acquiring data through the distance-based test and setting the threshold value by executing the calculation program, it is necessary to check the number of persons who are performing the test and the occurrence of an alarm, . In addition, the person adjusting the threshold must basically be able to deal with basic background knowledge of radar and specific computer programs. In addition, basic equipment is also required, since the signal must be checked directly from the computer through the computer.

In this way, there is a risk that the detection performance of the radar is largely influenced not only by the human, material, and temporal loss, but also by the skill level of the person adjusting the sensitivity.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a radar device and a control method thereof that can automatically set a threshold value in an environment adaptive manner.

According to another aspect of the present invention, there is provided a method of controlling an environmentally adaptive automatic setting radar apparatus, the method comprising: receiving a first signal corresponding to a temporal change amount of a first radar signal of a frequency falling period having a first range bin, And generating a second signal corresponding to a temporal change amount of a second radar signal in a frequency rising period having the first range bin, generating a second signal corresponding to a first radar filtered low- Generating a third signal by using a second filtered signal obtained by low-pass-filtering the signal; and generating a third signal by using a third radar of the frequency falling period having the first signal, the second signal, the third signal, A fourth signal corresponding to a temporal change amount of a signal and a fifth signal corresponding to a time variation amount of a fourth radar signal in a frequency rising section having the second range bin, Generating a sixth signal obtained by amplifying an intrusion signal component by combining the first signal and the second signal, obtaining an automatic limit value in the first range bin using the third signal, And detecting an intrusion based on the received signal.

The time variation of the signal can be obtained by combining one or more variation data obtained by a difference between the current signal and the previous time signals in a predetermined method.

The predetermined method may be defined as a maximum value, a minimum value, or an average value of one or more change amount data.

The third signal may be a signal superimposed by multiplying the first filtered signal and the second filtered signal.

The sixth signal may be a signal obtained by dividing the first signal, the second signal, the fourth signal, and the fifth signal by a value corresponding to the third signal.

The sixth signal is obtained by converting the first signal, the second signal, the fourth signal, and the fifth signal into a constant value corresponding to a section to which each signal value belongs, 3 < / RTI > signal.

Further comprising removing a peak noise signal component in the sixth signal and detecting an intrusion by comparing the automatic limit value with the sixth signal from which the peak noise signal component has been removed.

According to an aspect of the present invention, there is provided an environmentally adaptive automatic setting radar apparatus including: a first signal corresponding to a time variation amount of a first radar signal of a frequency falling period having a first range bin; A signal variation amount processing section for generating a second signal corresponding to a temporal change amount of a second radar signal in a frequency rising section having a first range bin, and a signal processing section for performing a low-pass filtering on the first radar signal and the second radar signal, A first low-pass filter for outputting a first filtered signal and a second filtered signal, a filtering signal superimposing unit for generating a third signal using the first filtered signal and the second filtered signal, A fourth signal corresponding to a time variation amount of a third radar signal of a frequency falling period having the second signal, the third signal, and the second range bin, A signal amplifying unit for generating a sixth signal obtained by amplifying an intruding signal component by combining a fifth signal corresponding to a temporal change amount of a fourth radar signal of a low frequency rising section in a predetermined method, And a detection unit for detecting an intrusion based on the automatic limit value in the first range bin and the sixth signal.

The apparatus may further include a second low-pass filter section for removing a peak noise signal component from the sixth signal.

The detection unit may detect an intrusion by comparing the sixth signal from which the peak noise signal component is removed with the automatic threshold value.

According to the present invention, there is an advantage that the threshold value can be calculated and applied automatically by analyzing the change amount of the environmental noise.

1 is a block diagram showing a configuration of a radar apparatus according to an embodiment of the present invention.
FIG. 2 is a view for explaining matters to be considered when selecting a method of combining variation data to extract signal variation according to the present invention. FIG.
3 to 5 are graphs for explaining a result of processing a radar signal according to an embodiment of the present invention.
6 is a graph showing that the threshold value according to the present invention is automatically set.
FIG. 7 shows an example of displaying a radar signal and an automatic limit value on which a signal amplification process according to an embodiment of the present invention is performed.
8 is a flowchart illustrating an operation of a radar apparatus according to an embodiment of the present invention.
FIG. 9 is a view for explaining a method of setting a threshold value through a conventional distance-based test.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

1 is a block diagram showing a configuration of a radar apparatus according to an embodiment of the present invention.

1, a radar apparatus 100 according to an embodiment of the present invention includes a fast Fourier transform unit 110, a signal variation amount processing unit 120, a first low pass filter unit 130, a filtering signal superimposing unit 140, a signal amplification unit 150, a second low-pass filter unit 160, and a detection unit 170.

The radar device 100 transmits a radar signal to the monitored area and processes the radar signal reflected from the monitored area to detect the object. The radar device 100 may be implemented as a Frequency Modulation Continuous Wave (FMCW) radar.

The fast Fourier transform unit 110 can perform Fast Fourier Transform (FFT) on the radar signal reflected and input in the surveillance region. (Bin, t) corresponding to the first radar signal (Signal.fall (bin, t)) corresponding to the falling period in which the frequency increases and the radar signal And a second radar signal (Signal.rise (bin, t)).

The first radar signal Signal.fall (bin, t) and the second radar signal Signal.rise (bin, t) include distance information bin and time information t. The distance information bin is a basic unit for processing the receiving radar signal by unit distance. It may vary depending on the embodiment, but corresponds to approximately 1 bin = 1.84 m. It should be understood by those skilled in the art that the radar signal includes distance information and time information, and a detailed description thereof will be omitted.

The signal variation amount processing section 120 can generate the signal SSR (bin, t) corresponding to the time variation amount of the radar signal (bin, t) having the first range bin.

The time variation of the signal can be obtained by combining one or more variation data obtained by the difference between the current signal and the previous time signals in a predetermined method.

For example, the first signal SSR.bin_fall (bin, t) corresponding to the time variation of the first radar signal (Signal.fall (bin, t)) can be obtained by the following equation (1).

[Equation 1]

(Bin, t-1) - (Signal.fall (bin, t-1) - (Signal, (bin, t-m + 1) - (Signal.fall (bin, tm)}]

Here, Signal.fall (bin, t) is the current signal of the radar signal of the frequency falling period having the first range bin. Signal.fall (bin, t-m) is the signal of the m-th previous time (t-m) of Signal.fall (bin, t). m is a natural number and can be set by the operator. For example, when only the change amount data of the current signal and the immediately preceding signal are to be used, m may be set to one. The MTI function can be defined to extract the maximum value, the minimum value, or the average value of the m pieces of change amount data as the signal change amount. Of course, it is also possible to define an MTI function to extract the signal variation amount by combining m pieces of change amount data by other methods.

FIG. 2 is a view for explaining matters to be considered when selecting a method of combining variation data to extract signal variation according to the present invention. FIG.

In the case of extracting the minimum value from the change amount data by the signal change amount, there is an advantage that the signal of a steadily increasing amount as shown in FIG. 2 (a) is small but the impulsive signal can be filtered out. However, more attention should be given to the intrusion signal amplification section.

On the other hand, when extracting the maximum value from the change amount data by the signal change amount, only a portion having a large signal change amount is obtained, as shown in FIG. 2 (b), but it is probable that the impulse signal becomes an error. Therefore, in order to reduce the possibility of an error in the impulse signal, it is necessary to consider a gap value which compensates the automatically set limit value to be described later.

The signal variation amount processing unit 120 applies the MTI function to the second radar signal Signal.rise (bin, t) in the frequency rising period to generate the second signal SSR. bin_rise (bin, t)).

&Quot; (2) "

(Bin, t-1) - (Signal.rise (bin, t-1) - (Signal, (bin, t-m + 1) - (Signal.rise (bin, tm)}]

On the other hand, the amount of signal variation obtained for the bin before or after the first range bin can also be used to amplify the intrusion signal component. The signal variation amount in the second range bin (b-1) obtained by the following equations (3) and (4) can be reflected in the intrusion signal component amplification.

&Quot; (3) "

1, t-1)}, {(Signal.fall (bin-1, t) - (Signal- 1) - (Signal.fall (bin-1, t-2)}, ..., {(Signal.fall (bin- ]

&Quot; (4) "

(Bin-1, t-1)}, {(Signal.rise (bin-1, t) - 1) - (Signal.rise (bin-1, t-2)}, ..., {(Signal.rise (bin- ]

In this case, the signal SSR (bin, t) input to the signal amplifier 150 is divided into a first signal SSR.bin_fall (bin, t), a second signal SSR.bin_rise 4 signal SSR.bin_1_fall (bin, t), and a fifth signal SSR.bin_1_rise (bin, t).

1, signals SSR.bin_1_fall (bin, t) and signals SSR.bin_1_rise (bin, t) from another block of the radar device 100 that processes the radar signals of the second range bin b- bin, t) may be provided to the signal change amount processing unit 120 or the signal amplification unit 150.

The first low pass filter 130 receives a signal (bin (t)) from a radar signal (bin, t) and performs low pass filtering to pass only a signal component of a predetermined frequency or less. The low-pass filtered signal LPF (Signal (bin, t)) may be a first filtered signal LP.signal.fall (bin, t) and a second filtered signal LP.signal.fall (bin, t). rise (bin, t)).

The filtering signal superimposing unit 140 multiplies the first filtered signal LP.signal.fall (bin, t) and the second filtered signal LP.signal.rise (bin, t) by Equation (5) The third signal LPF.SSR (bin, t) can be generated by using the function f ₂ () as a variable.

&Quot; (5) "

LPF.SSR (bin, t) = f 2 (LP.signal.fall (bin, t), LP.signal.rise (bin, t))

Function f ₂ () is a first filtered signal (LP.signal.fall (bin, t)) and the signal (LP.signal.rise (bin, t)) of the second filter as a variable.

The filtering signal superimposing unit 140 most simply multiplies the first filtered signal LP.signal.fall (bin, t) by the second filtered signal LP.signal.rise (bin, t) And generate a third signal LPF.SSR (bin, t) by overlapping. Of course, other methods may be used.

The signal amplifying unit 150 amplifies the signal SSR (bin, t) corresponding to the temporal change amount of the radar signal (bin (t)) having the first range bin and the third signal LPF.SSR bin, t)) to generate a sixth signal (SSR superposition (bin, t)) in which the intrusion signal component is largely amplified.

&Quot; (6) "

SSR superposition (bin, t) = f ₁ (SSR.bin_fall (bin, t), SSR.bin_rise (bin, t), SSR.bin_1_fall (bin, t))

Function f ₁ () it can be designed to amplify the break signal component in combination according to a predetermined method by a first signal to a fifth signal as a variable. For example, signal processing for multiplying the first signal, the second signal, the fourth signal, and the fifth signal and dividing the superimposed signal by the value of the third signal can be performed. Of course, the first signal to the fifth signal may be combined with each other to perform signal amplification.

In Equation (6), the signal SSR (bin, t) corresponding to the time variation is the first signal SSR.bin_fall (bin, t), the second signal SSR.bin_rise (SSR.bin_1_fall (bin, t)) and a fifth signal (SSR.bin_1_rise (bin, t)).

According to the embodiment, the function f ₁ () is a constant value corresponding to a section to which the value of the corresponding signal belongs using the conversion table as shown in Table 1 below as the first signal, the second signal, the fourth signal, and the fifth signal It may be designed to first convert and then process.

section Constant value 1 to less than 10 0.01 10 to less than 30 0.1 30 to less than 60 60 60 to less than 100 100 100 or more 200

The second low pass filter 160 may perform low pass filtering to remove a peak noise component of the signal amplified by the signal amplifier 150. It is also possible to omit low-pass filtering in the second low-pass filter 160 according to the embodiment.

The detection unit 170 detects a sixth signal SSR superposition (bin, t) output from the signal amplification unit 150 and a third signal LPF.SSR (bin, t) output from the filtering signal superposition unit 140. [ ) Can be used to detect intrusions.

The detection unit 170 may use the third signal LPF.SSR (bin, t) as an automatic threshold value, and set a gap value to reduce the possibility of an error due to a sudden change in environment, Signal (LPF.SSR (bin, t)). Here, the value for supplementing the automatic limit value can be set differently for the range bin.

The detection unit 170 compares the sixth signal output from the signal amplification unit 150 with the automatic limit value to detect whether or not the intrusion has occurred.

3 to 5 are graphs for explaining a result of processing a radar signal according to an embodiment of the present invention.

FIG. 3 (a) shows a radar signal at the time of intrusion occurring at 50 m, and FIG. 3 (b) shows a radar signal in which signal amplification processing according to the present invention has been performed.

4 (a) shows a radar signal when an intrusion occurs at 100 m, and Fig. 4 (b) shows a radar signal in which a signal amplification process according to the present invention is performed.

5 (a) shows a radar signal when a wind is blowing in a region where the detection area is a shrub, and Fig. 5 (b) shows a radar signal in which a signal amplification process according to the present invention is performed.

As shown in FIG. 3 to FIG. 5, when the signal amplification process according to the present invention is performed, it is confirmed that only the intrusion signal component is amplified by virtually eliminating the influence of environmental noise in a distance interval of 5 thousand or more.

6 is a graph showing that the threshold value according to the present invention is automatically set.

Referring to FIG. 6, it can be seen that the threshold value is automatically calculated and set according to the change of time and distance.

FIG. 7 shows an example of displaying a radar signal and an automatic limit value on which a signal amplification process according to an embodiment of the present invention is performed.

Fig. 7 (a) shows an example before intrusion detection, and Fig. 7 (b) shows an example after intrusion detection.

As shown in Figs. 7 (a) and 7 (b), it can be seen that the threshold value 1 is set automatically by the distance and time with the change. In addition, it can be confirmed that the signal (2) generated by the noise component to some extent is applied with a buffering function so as not to be falsified by applying the compensation value (Gap value). When the intrusion occurs in the vicinity of 50 m, it can be confirmed that the amplified signal 3 becomes more than the automatic limit value as shown in FIG. 7 (b) and an alarm occurs.

As described above, according to the present invention, it has been confirmed that the noise components due to the environment can be removed at a distance of about 5 thousand or more, and the signal processing can be performed so that only the intrusion signal is amplified. And it can be confirmed that the detection performance is improved and the error is improved by automatically calculating the threshold value by analyzing the change amount of the environmental noise.

8 is a flowchart illustrating an operation of a radar apparatus according to an embodiment of the present invention.

Referring to FIGS. 1 and 8, the fast Fourier transform unit 110 can perform Fast Fourier Transform (FFT) on the radar signal reflected and input in the surveillance region (S810).

Next, the signal variation amount processing section 150 can generate the signal SSR (bin, t) corresponding to the temporal variation amount of the radar signal (bin, t) having the first range bin (S820 ).

Meanwhile, the first low pass filter unit 130 performs low pass filtering that passes only a signal component of a predetermined frequency or less by receiving the radar signal Signal (bin, t) and outputs a filtered signal (LPF) the first filtered signal LP.signal.fall (bin, t) and the second filtered signal LPF (Signal (bin, t)) may be output (S830) LP.signal.rise (bin, t)).

Next, the filtering signal superimposing unit 140 performs a filtering operation on the basis of the first filtered signal LP.signal.fall (bin, t) and the second filtered signal LP.signal.rise (bin, t) the third signal LPF.SSR (bin, t) may be generated using f ₂ () (S840). (Bin, t)) and a second filtered signal (LP.signal.rise (bin, t)) to the first filtered signal (LP.signal.fall As a superimposed signal, it can be used to perform intrusion signal amplification processing in the signal amplification unit 150, and can be used particularly for calculating the automatic limit value according to the present invention.

The signal amplifying unit 150 then compares the signal SSR (bin, t) corresponding to the temporal change amount of the radar signal Signal (bin, t) having the first range bin and the signal SSR (bin, t)), the sixth signal SSR superposition (bin, t) in which the intrusion signal component is largely amplified (S850). Pass filtering to remove the peak noise signal component with respect to the sixth signal generated in operation S850. It is also possible to omit low-pass filtering in the second low-pass filter 160 according to the embodiment.

Finally, the detection unit 170 detects a sixth signal SSR superposition (bin, t) output from the signal amplification unit 150 and a third signal LPF.SSR (bin, t) output from the filtering signal superposition unit 140, t)) can be used to detect the intrusion (S860).

The detection unit 170 may use the third signal LPF.SSR (bin, t) as an automatic threshold value, and set a gap value to reduce the possibility of an error due to a sudden change in environment, Signal (LPF.SSR (bin, t)). Here, the value for supplementing the automatic limit value can be set differently for the range bin.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of the right.

100: Radar device
110: Fast Fourier transform unit
120: Signal change amount processor
130: a first low-pass filter section
140: Filtering signal overlapping section
150:
160: second low-pass filter section
170:

Claims (14)

Generates a first signal corresponding to a temporal change amount of a first radar signal in a frequency descending section having a first range bin and a second signal corresponding to a temporal variation amount of a second radar signal in a frequency rising section having the first range bin ,
Generating a third signal using a first filtered signal obtained by low-pass-filtering the first radar signal and a second filtered signal obtained by low-pass-filtering the second radar signal,
A fourth signal corresponding to a time variation amount of a third radar signal of a frequency falling period having the first signal, the second signal, the third signal, the second range bin, Generating a sixth signal obtained by amplifying an intrusion signal component by combining a fifth signal corresponding to a time variation amount of the fourth radar signal by a predetermined method,
Obtaining an automatic limit value in the first range bin using the third signal, and
Detecting an intrusion based on the sixth signal and the automatic limit value
And a control device for controlling the environment adaptive automatic setting radar device. The method of claim 1,
The amount of time variation of the signal,
Wherein the at least one change amount data obtained by a difference between the current signal and the previous time signals is obtained by a predetermined method. 3. The method of claim 2,
The predetermined method includes:
Wherein the maximum value, the minimum value, or the average value of the at least one change amount data is determined. 3. The method of claim 2,
Wherein the third signal comprises:
Wherein the first filtered signal and the second filtered signal are multiplied and superimposed on each other. 5. The method of claim 4,
The sixth signal may comprise:
And a signal obtained by dividing the first signal, the second signal, the fourth signal, and the fifth signal by a value corresponding to the third signal. 5. The method of claim 4,
The sixth signal may comprise:
The first signal, the second signal, the fourth signal, and the fifth signal into a constant value corresponding to an interval in which the value of each signal belongs, and then multiplying the multiplied values by a value corresponding to the third signal The control method of the environmentally adaptive automatic setting radar device. The method according to claim 5 or 6,
Removing the peak noise signal component from the sixth signal
Further comprising:
A method of controlling an environmentally adaptive automatic setting radar apparatus for detecting an intrusion by comparing the sixth signal from which a peak noise signal component is removed and the automatic threshold value. Generates a first signal corresponding to a temporal change amount of a first radar signal in a frequency descending section having a first range bin and a second signal corresponding to a temporal variation amount of a second radar signal in a frequency rising section having the first range bin A signal variation amount processor,
A first low pass filter unit for performing low pass filtering on the first radar signal and the second radar signal and outputting the first filtered signal and the second filtered signal,
A filtering signal superimposer for generating a third signal using the first filtered signal and the second filtered signal,
A fourth signal corresponding to a time variation amount of a third radar signal of a frequency falling period having the first signal, the second signal, the third signal, the second range bin, A signal amplifying unit for generating a sixth signal obtained by amplifying an intrusion signal component by combining a fifth signal corresponding to a temporal change amount of the fourth radar signal by a predetermined method, and
And a detection unit for detecting an intrusion based on the automatic limit value in the first range bin and the sixth signal obtained using the third signal,
And an environment-adaptive automatic setting radar device. 9. The method of claim 8,
The amount of time variation of the signal,
Adaptive automatic setting radar apparatus is obtained by combining at least one change amount data obtained by a difference between a current signal and previous time signals by a predetermined method. The method of claim 9,
The predetermined method includes:
Wherein the maximum value, the minimum value, or the average value of the at least one change amount data is set to a maximum value, a minimum value, or an average value. The method of claim 9,
Wherein the third signal comprises:
And the first filtered signal and the second filtered signal are multiplied and superimposed on each other. 12. The method of claim 11,
The sixth signal may comprise:
And a signal obtained by dividing the first signal, the second signal, the fourth signal, and the fifth signal by a value corresponding to the third signal. 12. The method of claim 11,
The sixth signal may comprise:
The first signal, the second signal, the fourth signal, and the fifth signal into a constant value corresponding to an interval in which the value of each signal belongs, and then multiplying the multiplied values by a value corresponding to the third signal , Which is an environment adaptive automatic setting radar device. 14. The method according to claim 12 or 13,
A second low-pass filter unit for removing a peak-noise signal component from the sixth signal,
Further comprising:
The detection unit detects,
And an environmentally adaptive automatic setting radar device for detecting an intrusion by comparing the sixth signal from which a peak noise signal component is removed with the automatic threshold value.

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