KR20200009306A - Method and apparatus for detecting interference signal using wavelet transform - Google Patents

Abstract

A method for detecting an interference signal using wavelet transform comprises the steps of: performing direct analog to digital (AD) conversion on a received signal in a radio frequency (RF) band; obtaining a first band signal and a second band signal by performing discrete wavelet transform on the AD converted signal; and estimating whether each of the first band signal and the second band signal includes an interference signal.

Description

Method and apparatus for detecting interference signal using wavelet transform

The present disclosure relates to a method and apparatus for detecting an interference signal using wavelet transform.

The received signal power of satellite navigation systems such as GPS in the US, GLONASS in Russia, Galileo in Europe, and Beidous in China is less than the noise power and is therefore greatly affected by the interference signal. In particular, when the intentional narrowband jamming signal is used, signal reception of the satellite navigation system may be easily interrupted even when the jamming signal is not large in power. When a particular navigation system is jammed, the bands that are interfering need to be estimated to receive signals from other navigation systems or other bands.

Interference signals are typically detected by measuring the desired narrow band signal power or by estimating signal-to-noise power ratio (SNR). A method of detecting an interference signal may be classified into a method of detecting an interference signal before analog-to-digital (AD) conversion and a method of detecting an interference signal after AD conversion.

A method of detecting an interference signal before AD conversion uses a fixed notch filter in a radio frequency (RF) band. Therefore, in order to detect an interference signal for several bands, several notch filters are required, and once a band is fixed, there is a disadvantage that cannot be changed.

Meanwhile, a general GNSS receiver converts a signal of a carrier band (ie, an RF band) to an intermediate frequency (IF) band and then performs AD conversion. In this case, the signal in the RF band may pass through a band-pass filter (BPF) before being converted to the IF band to prevent the overlap of the spectrum. Accordingly, the band of the signal may be narrowly limited, and the method of detecting the interference signal after the AD conversion has a disadvantage in that the presence or absence of interference is known only for the narrow band signal of the bandpass filter.

Various embodiments provide a method and apparatus for detecting an interference signal using wavelet transform. The technical problem to be achieved by the present disclosure is not limited to the technical problems as described above, and other technical problems may be inferred from the following embodiments.

As a means for solving the above technical problem, a method for detecting an interference signal using the wavelet transform according to an aspect, performing a direct AD (analog to digital) conversion for the received signal of the radio frequency (RF) band step; Acquiring a first band signal and a second band signal by performing a discrete wavelet transform on the AD transformed signal; And estimating whether each of the first band signal and the second band signal includes the interference signal.

Acquiring the first band signal and the second band signal includes dividing the entire frequency band of the AD converted signal by half by performing discrete wavelet transform on the AD converted signal, The first band signal may correspond to a high band signal, and the second band signal may correspond to a low band signal.

Estimating whether each of the first band signal and the second band signal includes the interference signal includes: calculating an average power of each of the first band signal and the second band signal; And estimating a signal having the calculated average power among the first band signal and the second band signal higher than a preset threshold value as a signal including the interference signal.

을 따를 수 있다.If the average power of the signal not including the interference signal is P ₀ and the interference signal is included in the received signal, the coefficient value of an automatic gain controller does not include the interference signal in the received signal. When it is 1 / a times compared with the case, the preset threshold value P _th is expressed as

You can follow

The method may include determining whether a frequency band of a signal estimated to include the interference signal corresponds to a desired resolution as a result of the estimation; Acquiring a third band signal and a fourth band signal by performing discrete wavelet transform on the signal estimated to include the interference signal when the frequency band of the signal estimated to include the interference signal does not correspond to a desired resolution; ; And estimating whether the interference signal is included in each of the third band signal and the fourth band signal.

In addition, obtaining a third band signal and a fourth band signal by performing discrete wavelet transform on the signal estimated to include the interference signal may include half downsampling a signal estimated to include the interference signal. Performing; And acquiring the third band signal and the fourth band signal by performing discrete wavelet transform on the downsampled signal.

Meanwhile, the method may further include not performing additional discrete wavelet transform on the signal estimated to include the interference signal when the frequency band of the signal estimated to include the interference signal corresponds to a desired resolution. have.

The method may further include not performing additional discrete wavelet transform on a signal estimated as not including the interference signal as a result of the estimation.

In addition, the computer-readable recording medium according to another aspect may include a recording medium on which one or more programs are recorded including instructions for executing the above-described method.

In addition, an apparatus for detecting an interference signal using wavelet transform according to another aspect, the RF sampling receiver for performing an AD conversion directly on the received signal of the RF band; And obtaining a first band signal and a second band signal by performing discrete wavelet transform on the AD transformed signal, and estimating whether each of the first band signal and the second band signal includes the interference signal. It may include a control unit.

The present disclosure can provide a method and apparatus for detecting an interference signal using wavelet transform. Specifically, the method and apparatus according to the present disclosure obtains the first band signal and the second band signal by performing direct AD conversion on the received signal of the RF band and performing discrete wavelet transform on the AD converted signal. It may be estimated whether each of the first band signal and the second band signal includes an interference signal.

The method and apparatus for detecting an interference signal according to the present disclosure performs AD conversion directly on a received signal of an RF band, and thus can be applied to a wideband signal having a very wide bandwidth, and simultaneously for an L2 band as well as an L1 band of a GNSS signal. It is possible to estimate whether an interference signal is introduced.

Since the method and apparatus for detecting an interference signal according to the present disclosure gradually estimate a band in which interference exists by dividing by 1/2, it is possible to elastically estimate whether an interference signal is introduced to a bandwidth having a desired resolution.

In addition, the method and apparatus for detecting an interference signal according to the present disclosure gradually divides and processes the broadband by 1/2, and does not perform additional wavelet transformation for a band not including the interference signal, thereby calculating the interference signal. The complexity of can be reduced.

Since the method and apparatus for detecting an interference signal according to the present disclosure can simultaneously estimate a band that does not include an interference signal over a wide band, the method and apparatus can be applied to a wireless cognitive technology that transmits a variable band.

1 is a flowchart illustrating a method of detecting an interference signal using wavelet transform according to an exemplary embodiment.
FIG. 2 is a diagram for describing a process of dividing a band by repeatedly applying a wavelet transform filter according to some embodiments.
3 is a diagram illustrating a frequency band corresponding to an output signal of each wavelet transform filter according to some embodiments.
4 is a diagram illustrating a method of estimating whether an interference signal is included in an output signal of a wavelet transform filter according to an exemplary embodiment.
5 is a block diagram illustrating a configuration of an apparatus for detecting an interference signal using wavelet transform according to some embodiments.

Hereinafter, only exemplary embodiments will be described in detail with reference to the accompanying drawings. It is to be understood that the following description is only intended to embody the embodiments, but not to limit or limit the scope of the invention. From the detailed description and examples, what can be easily inferred by those skilled in the art is construed as falling within the scope of the right.

As used herein, the term “consisting of” or “comprising” should not be construed as including all of the various components or steps described in the specification, and some or some of them may be included. Should not be included or should be construed to further include additional components or steps.

In addition, terms including ordinal numbers such as 'first' or 'second' as used herein may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terminology used herein is to select general terms that are currently widely used as possible in consideration of the functions in the present invention, but may vary according to the intention or precedent of the person skilled in the art, the emergence of new technologies and the like. In addition, in certain cases, there is a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the invention. Therefore, the terms used in the present invention should be defined based on the meanings of the terms and the general contents of the present invention, rather than simply the names of the terms.

The embodiments of the present invention relate to a method and an apparatus for detecting an interference signal using wavelet transform, and detailed descriptions of the matters well known to those skilled in the art to which the following embodiments belong will be omitted.

1 is a flowchart illustrating a method of detecting an interference signal using wavelet transform according to an exemplary embodiment. The method of FIG. 1 may be performed by an apparatus for detecting an interference signal using wavelet transform.

In operation 110, the device may directly perform an analog to digital (AD) conversion on a received signal in a radio frequency (RF) band. The direct AD conversion may refer to a method of directly converting a signal of a carrier band without frequency conversion, unlike the method of performing AD conversion after converting a signal of a carrier band (that is, an RF band) into an intermediate frequency band. The apparatus can directly sample the received signal of the RF band by performing AD conversion directly on the received signal of the RF band. Accordingly, a wideband digital signal corresponding to the antenna bandwidth can be obtained.

Since the method for detecting an interference signal according to the present disclosure performs AD conversion directly on a received signal of an RF band, it can be applied to a wide bandwidth signal having a very wide bandwidth, and simultaneously interferes with the L2 band as well as the L1 band of the GNSS signal. It can be estimated whether the inflow of.

In operation 120, the device may obtain a first band signal and a second band signal by performing a discrete wavelet transform (DWT) on the AD transformed signal. The discrete wavelet transform has a characteristic of dividing the entire frequency band by 1/2 in order by performing scaling. In this case, the wide band signal requires a signal having a relatively short length compared to the narrow band signal. For example, the bandwidth B ₀ Hz, while in order to detect the signal of at least 1 / B _0-second signal is required, the bandwidth B _0/2 of the signal is required in 2 / B _0-second signal in order to detect the Do. Therefore, only a signal for a very short time may be required to detect whether an interference signal is included in a signal in which AD conversion is directly performed on a received signal of a wide band, that is, an RF band.

The apparatus may divide the entire frequency band of the AD-converted signal by half by performing discrete wavelet transform on the AD-converted signal by using the aforementioned characteristic. The first band signal among the divided signals may correspond to the high band signal, and the second band signal may correspond to the low band signal. Hereinafter, a process of performing discrete wavelet transform on the AD-converted signal by the apparatus will be described in more detail with reference to FIGS. 2 and 3.

FIG. 2 is a diagram illustrating a process of dividing a band by repeatedly applying a wavelet transform filter according to some embodiments. FIG. 3 is a diagram illustrating a frequency band corresponding to an output signal of each wavelet transform filter according to some embodiments. It is a figure which shows.

Referring to FIG. 2, an example in which a process of gradually dividing a band by using a characteristic of discrete wavelet transform is performed up to three steps is illustrated. Meanwhile, acquiring the first band signal and the second band signal by performing discrete wavelet transform on the AD transformed signal throughout the specification may be expressed as passing the AD converted signal to the wavelet transform filter. In this case, each of the first band signal and the second band signal may correspond to a response of a high-pass wavelet filter and a response of a low-pass wavelet filter.

In one example, the device may apply a high pass and low pass wavelet filter for dividing the entire band in half for N samples of a wideband baseband signal x ₀₁ (n) for a short time. In FIG. 2, h (n) and g (n) each represent the impact response of the high pass and low pass wavelet filters. The high pass and low pass wavelet filters may have a relationship according to Equation 1 below.

In Equation 1, L represents the length of the filter.

Meanwhile, the apparatus may estimate whether each of the first band signal and the second band signal includes an interference signal, and to estimate the band including the interference signal more precisely, as described below. The two-band signal can be passed back to the high and low wavelet transform filters. At this point, the device may perform 1/2 downsampling, taking one sample every two before passing the first or second band signal back to the high and low wavelet transform filters. The device can maintain the same sample count as the previous sample count by doubling the time of the signal, taking into account that the sample count of the signal is reduced by half by downsampling. The doubling of the time of the signal may mean that when the number of samples of x _1m (n) (m is any natural number) is N, the number of samples of x ₀₁ (n) becomes 2N. The apparatus obtains filter responses x ₁₁ (n) and x ₁₂ (n) corresponding to each of the first band signal and the second band signal, and repeats the above-described method for each x _{1 m} (n) to set the band to 1. You can subdivide by / 2. The spectrum of each filter response including x ₁₁ (n) and x ₁₂ (n) is as shown in FIG. 3.

In operation 130, the device may estimate whether each of the first band signal and the second band signal includes an interference signal. The apparatus calculates an average power of each of the first band signal and the second band signal, and estimates a signal having an interference signal whose average power calculated among the first band signal and the second band signal is higher than a preset threshold. can do.

For example, the device may estimate that the first band signal includes an interference signal when the average power of the first band signal is higher than the preset threshold, and the average power of the second band signal is higher than the preset threshold. In this case, it may be estimated that the second band signal includes an interference signal. The apparatus may estimate that both the first band signal and the second band signal include an interference signal when both the average power of the first band signal and the average power of the second band signal are higher than a preset threshold. Hereinafter, a process of determining whether an interference signal is included in a signal of a specific band will be described in detail with reference to FIG. 4.

 4 is a diagram illustrating a method of estimating whether an interference signal is included in an output signal of a wavelet transform filter according to an exemplary embodiment.

을 계산할 수 있다.Referring to FIG. 4, a method of estimating the presence or absence of an interference signal with respect to the output signal x _{l, m} (n) of the m-th filter in step _l is illustrated. The device uses the following Equation 2 to output the average power of the output signal x _{l, m} (n)

Can be calculated.

In Equation 2, N represents the number of samples of the signal for which the average power is to be obtained.

와 기 설정된 임계값

를 비교할 수 있다. 출력신호 x_l,m(n)의 평균전력

이 기 설정된 임계값

보다 크다는 것은 해당 대역에 간섭신호가 포함되어 있다는 것을 나타낼 수 있다. 장치는 간섭신호가 유입되는 대역을 보다 정밀하게 추정하고자 하는 경우 신호를 다시 고역 및 저역 웨이블릿 필터에 통과시키고, 각 대역에서의 간섭유무를 추정할 수 있다. 이와 같이, 장치는 간섭이 유입된 대역에 대해 반복적으로 대역을 분할해 가면서 간섭 대역을 추정함으로써 원하는 해상도까지 정밀하게 간섭 주파수대를 추정할 수 있다. 본 개시에 따른 간섭신호를 검출하는 방법은 간섭이 존재하는 대역을 점차적으로 1/2씩 분할하여 추정하므로, 원하는 해상도의 대역폭까지 신축성 있게 간섭신호의 유입 여부를 추정할 수 있다.The device is the average power of the output signal x _{l, m} (n)

And preset thresholds

Can be compared. Average power of output signal x _{l, m} (n)

This preset threshold

A larger value may indicate that an interference signal is included in the corresponding band. The device may pass the signal back to the high and low wavelet filters to estimate the band in which the interference signal flows more accurately, and estimate the presence or absence of interference in each band. As such, the apparatus can estimate the interference frequency band precisely up to a desired resolution by repeatedly dividing the band with respect to the band into which the interference has been introduced. In the method for detecting an interference signal according to the present disclosure, since the band in which interference exists is gradually estimated by dividing by 1/2, it is possible to elastically estimate whether an interference signal is introduced to a bandwidth having a desired resolution.

For example, the device may determine whether a frequency band of a signal estimated to include an interference signal corresponds to a desired resolution. If the frequency band of the signal from which the interference signal is assumed to exist does not correspond to the desired resolution, the device may perform the discrete wavelet transform on the signal from which the interference signal is supposed to exist to obtain the third band signal and the fourth band signal. And whether the interference signal is included in each of the third band signal and the fourth band signal.

In this case, the device may obtain the third band signal and the fourth band signal by performing 1/2 downsampling on the signal estimated to exist and performing discrete wavelet transform on the downsampled signal. . Each of the third band signal and the fourth band signal may correspond to a high band signal and a low band signal when a frequency band of a signal estimated to include an interference signal is divided into half.

The apparatus may not perform additional discrete wavelet transform on the signal estimated to exist when the frequency band of the signal estimated to exist by the interference signal corresponds to the desired resolution. The apparatus detects an interference signal by dividing the band repeatedly using discrete wavelet transform until the frequency band of the signal where the interference signal is estimated to exist corresponds to a desired resolution, and indirect signal detection operation when the desired resolution is reached. Can be terminated.

In addition, the apparatus may not perform additional discrete wavelet transform on the signal that is estimated not to include the interference signal. In the method for detecting an interference signal according to the present disclosure, the broadband is gradually divided by 1/2, and no additional wavelet transform is performed for a band that does not include the interference signal, thereby reducing the complexity of the calculation for the interference signal estimation. Can be.

는 AD 변환기 이전에 위치하는 자동 이득 조절기(automatic gain controller: AGC)의 계수값 K_agc에 의해 결정될 수 있다. AGC는 AD 변환기에 입력되는 수신신호의 전력을 일정하게 유지하는 구성으로서, 간섭신호가 유입되어 신호의 전력이 간섭신호가 유입되지 않은 경우와 비교하여 a배 증가하는 경우 계수값을

로 조정할 수 있다. 간섭 간섭신호를 포함하지 않는 신호의 평균전력이 P₀이고, 수신신호에 간섭신호가 포함되는 경우의 AGC의 계수값이 수신신호에 간섭신호가 포함되지 않는 경우와 비교하여 1/a배가 된다고 할 때, 기 설정된 임계값 P_th는 다음과 같은 수학식 3을 따를 수 있다.Meanwhile, the preset threshold

Can be determined by the coefficient value K _agc of the automatic gain controller (AGC) located before the AD converter. AGC keeps the power of the received signal input to the AD converter constant. When the interference signal is introduced, the power of the signal increases by a times compared to the case where no interference signal is introduced.

Can be adjusted. The average power of a signal that does not contain an interference signal is P ₀ , and the coefficient value of AGC when the interference signal is included in the received signal is 1 / a times as compared with the case where the interference signal is not included in the received signal. At this time, the preset threshold P _th may follow Equation 3 below.

As shown in Equation 3, as a predetermined threshold value P _{th that} is compared with the output signal of the filter is determined, presence or absence of interference signal in each band can be accurately estimated.

Meanwhile, a method of detecting an interference signal using wavelet transform may be recorded in a computer-readable recording medium in which one or more programs including instructions for executing the method are recorded. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine code, such as produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter.

5 is a block diagram illustrating a configuration of an apparatus for detecting an interference signal using wavelet transform according to some embodiments. Referring to FIG. 5, an apparatus 50 for detecting an interference signal using wavelet transform may include an RF sampling receiver 510 and a controller 520. The apparatus 50 shown in FIG. 5 can process the method shown in FIG. 1 in time series. Therefore, even if omitted below, it can be seen that the contents described above with respect to the method of FIG. 1 can be performed by the apparatus 50 of FIG. 5.

On the other hand, only the components related to the present embodiment are shown in the apparatus 50 shown in FIG. Accordingly, it will be understood by those skilled in the art that the general purpose components other than the components shown in FIG. 5 may be further included in the device 50. For example, the device 50 may further include a memory (not shown).

The memory is hardware that stores various data processed within the device 50. For example, the memory may store data processed in the device 50 and data to be processed. In addition, the memory may store applications, drivers, and the like, to be driven by the device 50.

Memory is random access memory (RAM), such as dynamic random access memory (DRAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), CD-ROM, blue Ray or other optical disk storage, hard disk drive (HDD), solid state drive (SSD), or flash memory, and may further include other external storage devices accessible to device 50.

The RF sampling receiver 510 is a receiver included in the satellite navigation system, and may refer to a device that receives a received signal of an RF band and performs AD conversion on the received received signal. The RF sampling receiver 510 may directly sample the received signal of the RF band by performing direct AD conversion on the received signal of the RF band without frequency conversion. Accordingly, a wideband digital signal corresponding to the antenna bandwidth can be obtained. Meanwhile, the RF sampling receiver 510 may further include an AGC for maintaining a constant power of a received signal input to the AD converter in addition to the AD converter.

The controller 520 may be implemented by one or a plurality of processors. For example, the controller 520 may be implemented as an array of a plurality of logic gates, or may be implemented as a combination of a general purpose microprocessor and a memory in which a program that may be executed in the microprocessor is stored.

The controller 520 may acquire the first band signal and the second band signal by performing discrete wavelet transform on the AD converted signal. The controller 520 may divide the entire frequency band of the AD converted signal into 1/2 by performing discrete wavelet transform on the AD converted signal. At this time, the first band signal of the divided signals may correspond to the high-band signal, the second band signal may correspond to the low-band signal.

The controller 520 may estimate whether each of the first band signal and the second band signal includes an interference signal. For example, the controller 520 calculates an average power of each of the first band signal and the second band signal, and interferes with a signal whose average power calculated among the first band signal and the second band signal is higher than a preset threshold. It can be estimated as a signal including the signal.

On the other hand, the average power of the signal that does not include the interference signal is P ₀ , and the coefficient value of AGC when the interference signal is included in the received signal is 1 / a times as compared with the case where the interference signal is not included in the received signal. In this case, the preset threshold P _th may follow Equation 3 above.

The controller 520 determines whether the frequency band of the signal estimated to include the interference signal corresponds to the desired resolution, and if the frequency band of the signal estimated to exist does not correspond to the desired resolution, The third band signal and the fourth band signal may be obtained by performing discrete wavelet transform on the signal estimated to exist.

In one example, the controller 520 performs 1/2 downsampling on the signal estimated to exist and performs discrete wavelet transform on the downsampled signal to generate the third band signal and the fourth band signal. Can be obtained. In addition, the controller 520 may estimate whether the interference signal is included in each of the third band signal and the fourth band signal.

Meanwhile, the controller 520 may not perform additional discrete wavelet transform on the signal estimated to exist when the frequency band of the signal estimated to exist by the interference signal corresponds to a desired resolution. In addition, the controller 520 may not perform additional discrete wavelet transform on the signal estimated as not including the interference signal.

As described above, since the apparatus for detecting the interference signal according to the present disclosure gradually estimates the band in which the interference exists by dividing by 1/2, the apparatus can detect the bandwidth of the desired resolution flexibly, and the band does not include the interference signal. The complexity of the calculation for the interference signal estimation can be reduced by not performing an additional wavelet transform on.

In addition, since the apparatus for detecting the interference signal according to the present disclosure can simultaneously estimate a band that does not include the interference signal over a wide band, the apparatus for detecting an interference signal can be applied to a radio recognition technology that transmits a variable band.

Although the embodiments have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also within the scope of the present invention. Belongs to.

Claims (10)

In the method for detecting an interference signal using wavelet transform,
Performing an analog to digital (AD) conversion on a received signal in a radio frequency (RF) band;
Acquiring a first band signal and a second band signal by performing a discrete wavelet transform on the AD transformed signal; And
Estimating whether each of the first band signal and the second band signal includes the interference signal. The method of claim 1,
Acquiring the first band signal and the second band signal includes dividing the entire frequency band of the AD converted signal by half by performing discrete wavelet transform on the AD converted signal,
Wherein the first band signal corresponds to a high band signal and the second band signal corresponds to a low band signal. The method of claim 1,
Estimating whether each of the first band signal and the second band signal includes the interference signal,
Calculating an average power of each of the first band signal and the second band signal; And
Estimating a signal having the calculated average power among the first band signal and the second band signal higher than a preset threshold value as a signal including the interference signal. In accordance with claim 3,
The average power of the signal not including the interference signal is P ₀ , and the coefficient value of the automatic gain controller when the interference signal is included in the received signal does not include the interference signal in the received signal. When it is 1 / a times as compared with the case where not, the predetermined threshold value P _th is

Following, the way. The method of claim 1,
The method,
Determining whether a frequency band of a signal estimated to include the interference signal corresponds to a desired resolution as a result of the estimation;
Acquiring a third band signal and a fourth band signal by performing discrete wavelet transform on a signal estimated to include the interference signal when the frequency band of the signal estimated to include the interference signal does not correspond to a desired resolution; ; And
Estimating whether the interference signal is included in each of the third band signal and the fourth band signal. The method of claim 5,
Acquiring a third band signal and a fourth band signal by performing discrete wavelet transform on the signal estimated to include the interference signal,
Performing 1/2 downsampling on the signal estimated to include the interference signal; And
Obtaining the third band signal and the fourth band signal by performing discrete wavelet transform on the downsampled signal. The method of claim 5,
The method,
If the frequency band of the signal estimated to include the interference signal corresponds to a desired resolution, further comprising not performing further discrete wavelet transform on the signal estimated to include the interference signal. The method of claim 1,
The method,
And not performing additional discrete wavelet transform on the signal that is estimated to not include the interference signal as the result of the estimation. A computer-readable recording medium having recorded thereon one or more programs containing instructions for executing the method of claim 1. An apparatus for detecting an interference signal using wavelet transform,
An RF sampling receiver performing direct AD conversion on a received signal in an RF band; And
A control unit for obtaining a first band signal and a second band signal by performing discrete wavelet transform on the AD transformed signal, and estimating whether each of the first band signal and the second band signal includes the interference signal Including, the device.

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