KR101330852B1 - Cooperative spectrum sensing apparatus and method - Google Patents

Abstract

Disclosed are a collaborative spectrum sensing apparatus and method. The disclosed cooperative spectrum sensing device is configured to obtain usage state information (channel usage state information) of the channel obtained by spectrum-sensing the channel multiple times for a predetermined time by two or more next-order users who want to use the channel applied to the priority user. Receiving unit for receiving from the next higher-order users; A detector configured to analyze the distribution of the channel usage state information for the predetermined time for each of the at least two next-order users and detect at least one malicious user among the at least two next-order users; And whether the channel is being used by the priority user by using the remaining channel usage information except for the channel usage information received from the at least one malicious user among the channel usage status information received from the at least two next-order users. It includes a judgment unit for judging.

Description

Cooperative Spectrum Sensing Apparatus and Method {COOPERATIVE SPECTRUM SENSING APPARATUS AND METHOD}

Embodiments of the present invention relate to a cooperative spectrum sensing device and method, and more particularly, to a cooperative spectrum sensing device and method that can accurately calculate the probability that a channel assigned to a priority user is being used by the priority user. It is about.

Spectrum sensing techniques for accurately detecting the presence of a priority user (i.e. authorized user) (i.e. whether an authorized channel is being used by a priority user) are very important elements in a cognitive wireless communication system. This means that if spectrum sensing fails and the next-level user (unauthorized user) is unaware of the existence of the first-priority user, the next-level user will send the data using that authorization channel while the priority user uses that authorization channel. This is because a conflict occurs between the priority user and the next user.

However, due to shadowing and multipath fading, it is difficult to accurately perform spectrum sensing on a channel in a wireless environment.

Cooperative Spectrum Sensing is a spectral sensing method designed to overcome the uncertainty of channel sensing. In collaborative spectrum sensing, Local Sensing Data, which is the result of spectrum sensing collected by each of two or more geographically dispersed subordinate users, is collected by the Fusion Center, and the Fusion Center receives two or more Local sensing data collected from next-order users is used to determine whether a priority user is using an authorization channel.

According to this cooperative spectrum sensing method, even though some of the next-order users do not detect the presence of the priority users due to deep fading, the priority is determined by using local sensing data collected from other next-order users who do not suffer from severe fading. The presence of a ranking user can be detected, thereby increasing the accuracy of spectrum sensing (ie, accurately detecting the presence of a priority user).

Despite the advantages of cooperative spectrum sensing, if there are malicious next-order users among the next-order users, the efficiency of cooperative spectrum sensing may be degraded. In particular, some malicious users send intentionally distorted local sensing data to the Fusion Center, causing errors in the final sensing results. That is, some malicious users send sensing data to the Fusion Center indicating that the channel is being used by the priority user even though the priority user is not using the authorized channel, thereby causing false alarm probability. ) Increases, reducing the chance of other non-malware users using the authorized channel.

According to a prior art outlier detection technique for detecting such malicious users, as shown in FIG. 1, the fusion center 110 receives sensing values received from two or more next-order users 121, 122, 123, and 124. Among them, the next-order user 124 that transmits the sensing value 15.4, which is significantly different from other sensing values, to the fusion center 110 is detected as a malicious user.

However, the outlier detection technique has a disadvantage in that the performance of spectrum sensing is degraded in a channel environment having a small signal-to-noise ratio (SNR). This is because, as the power of noise increases, it is difficult to distinguish between a sensing value caused by noise and a false value detected by a malicious user.

In order to solve the problems of the prior art as described above, the present invention proposes a cooperative spectrum sensing apparatus and method that can accurately calculate the probability that the channel assigned to the priority user is being used by the priority user.

Other objects of the invention will be apparent to those skilled in the art from the following examples.

According to a preferred embodiment of the present invention to achieve the above object, the use of the channel obtained by the two or more next-order users who want to use the channel authorized to the priority user obtained by spectral sensing the channel multiple times for a predetermined time A receiver for receiving status information (channel usage status information) from the at least two next-order users; A detector configured to analyze the distribution of the channel usage state information for the predetermined time for each of the at least two next-order users and detect at least one malicious user among the at least two next-order users; And whether the channel is being used by the priority user by using the remaining channel usage information except for the channel usage information received from the at least one malicious user among the channel usage status information received from the at least two next-order users. There is provided a cooperative spectrum sensing device comprising a determination unit for determining.

The spectrum sensing is spectrum sensing based on energy detection, and the channel usage state information may include an energy value of a signal detected in the channel.

The detector may be configured to generate an energy value in which a ratio of channel use state information having an energy value greater than a reference energy value among the channel use state information transmitted by any one of the second or more next-order users is less than the reference energy value. If the branch has a threshold ratio greater than the ratio of the channel use state information, the next rank user may be detected as a malicious user.

The detection unit compares a channel usage model for a malicious user, a channel usage model for a malicious user, and an analysis result of distribution of channel usage information for each of the two or more next-order users, and compares the results of the analysis. The one or more malicious users can be detected.

The channel usage state model for the non-malignant user has a distribution in which the ratio of channel usage state information having an energy value greater than a reference energy value is greater than the ratio of the channel usage state information having an energy value less than the reference energy value. Can have

The detector uses a goodness of fit test technique to distribute the channel usage state information for each of the two or more next-order users to the channel usage state model for the non-malicious user and the channel usage state for the malicious user. It may be determined which channel usage state model is similar to the model.

The fitness check technique may be an Anderson-Darling technique.

In addition, according to another embodiment of the present invention, the use state information of the channel obtained by two or more next-order users who want to use the channel authorized to the priority user by spectral sensing the channel a plurality of times for a predetermined time (channel use state Receiving information) from the two or more next-order users; Analyzing the distribution of the channel usage state information for the predetermined time for each of the at least two next-order users and detecting at least one malicious user from the at least two next-order users; And whether the channel is being used by the priority user by using the remaining channel usage information except for the channel usage information received from the at least one malicious user among the channel usage status information received from the at least two next-order users. A cooperative spectrum sensing method comprising determining is provided.

According to the present invention, it is possible to accurately calculate the probability that the channel assigned to the priority user is being used by the priority user.

1 is a view for explaining the prior art.
2 is a diagram illustrating a schematic configuration of a cognitive radio network according to an embodiment of the present invention.
FIG. 3 is a diagram for explaining distribution of channel usage state information of a non-malicious user and distribution of channel usage state information of a malicious user.
4 to 6 are diagrams showing simulation results using the cooperative spectrum sensing apparatus according to an embodiment of the present invention.
7 is a flowchart illustrating the overall flow of the cooperative spectrum sensing method according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a diagram illustrating a schematic configuration of a cognitive radio network according to an embodiment of the present invention.

Referring to FIG. 2, the cognitive radio network 200 includes one priority user 210, two or more next-order users 220, and a cooperative spectrum sensing device 230 and a base station 240. Here, the cooperative spectrum sensing device 230 may correspond to the fusion center described above, and includes a receiver 231, a detector 232, and a determiner 233. Hereinafter, the function of each component will be described in detail with reference to FIG. 2.

Priority user 210 is a user authorized to use the right to the channel (hereinafter referred to as "authorized channel") formed between the base station 240, the two or more next-order users 220 is a cognitive radio communication Unauthorized user who wants to use authorized channel through In this case, it is assumed that one or more malicious users 220a intending to exclusively use the authorization channel exist during the period in which the priority user does not use the authorization channel among the two or more next-order users 220.

Each of the two or more next-order users 220 generates channel usage information by spectral sensing the applied channel a plurality of times for a predetermined time, and transmits the channel usage state information to the cooperative spectrum sensing device 230.

According to an embodiment of the present invention, the two or more next-order users 220 may generate channel usage information by performing energy sensing based spectrum sensing on an authorized channel. In this case, the channel use state information may include an energy value of a signal sensed in the applied channel.

Therefore, if the priority user does not use the authorized channel, since only a noise signal exists in the channel, the channel usage information has a relatively low energy value. On the contrary, when the priority user uses the authorization channel, since the signal transmitted by the priority user and the noise signal exist together, the channel usage information has a relatively high energy value.

The cooperative spectrum sensing device 230 that has received channel usage information for a predetermined time from each of the next-order users 220 through the receiver 231 uses the same to use one or more malicious ones from among the second-order users 220. ) Detect the next-order user 220a.

In addition, the determination unit 233 may use the remaining channel usage state information except for channel usage state information received from at least one malicious user among channel usage state information received from two or more next-order users 220. Determine if it is being used by the ranking user. In other words, the determination unit 233 performs cooperative spectrum sensing using the remaining information except for the information transmitted from the malicious user.

Hereinafter, an operation of detecting the malicious user by the detector 232 will be described in more detail.

The detector 232 detects one or more malicious users 220a among two or more next-order users 220 by analyzing the distribution of channel usage state information for the predetermined time for each next-order users 220.

In this case, since the non-malicious next-order user transmits the unmanipulated channel usage information to the cooperative spectrum sensing device 230, the energy value of the channel usage information received from the non-malicious users for a predetermined time. May have a high energy value or may have a low energy value. Therefore, the energy value distribution of the channel usage state information received from the non-malicious user for a predetermined time may be the same as the graph shown in FIG.

However, since the malicious user wants to use the authorization channel exclusively during the period when the authorization channel is not being used by the priority user, the authorization channel is continuously used by the priority user to prevent non-malicious users from using the authorization channel. Distorted channel usage information is transmitted. Therefore, most energy values of channel usage information received from malicious users for a predetermined time have a high energy value. Therefore, the energy value of the channel usage state information received from the malicious user for a predetermined time may be the same as the graph shown in FIG.

According to an embodiment of the present invention, the detection unit 232 has channel usage state information having an energy value greater than a reference energy value among channel usage state information transmitted by any one of the second or more next-order users 220. If the ratio is greater than or equal to the threshold ratio than the ratio of the channel usage state information having an energy value smaller than the reference energy value, any one of the next-order users may be detected as a malicious user. At this time, the critical ratio can be determined experimentally.

For example, in the case of (a) of FIG. 3, when the reference energy value is set to 30, in the case of a non-malicious user, channel usage state information having an energy value of 30 or more and channel usage state information having an energy value of 30 or less are included. Since it is relatively evenly distributed, the ratio of channel usage state information having an energy value of 30 or more and the ratio of channel usage state information having an energy value of 30 or less among the total channel use state information are not relatively large. However, in FIG. 3B, it can be seen that the ratio of channel use state information having an energy value of 30 or more is much higher than the ratio of channel use state information having an energy value of 30 or less. Accordingly, the detection unit 232 classifies the next-order user who has transmitted the channel usage state information having the distribution as shown in FIG. 3A as a non-malicious user, and uses the channel usage state information having the distribution as shown in FIG. 3B. The next-order user who transmits the data can be classified as a malicious user.

In addition, according to an embodiment of the present invention, the detection unit 232 is a channel usage model preset for the non-malicious user and the channel usage model preset for the malicious user and each of the two or more next-order users 220 One or more malicious users 220a may be detected by comparing analysis results of distribution of channel usage state information. In this case, as described above, the channel usage model for the non-malicious user has a critical ratio of the channel usage state information having an energy value greater than the reference energy value than the ratio of the channel usage information information having an energy value less than the reference energy value. It can have a large distribution.

At this time, the detection unit 232 is a channel use state model for the non-malware user analysis results of the distribution of the channel use state information for each of the two or more next-order users 220 using a goodness of fit test (Goodness of Fit Test) technique And which channel usage model of the channel usage model for the malicious user is more similar. This will be described in detail below.

For the goodness-of-fit check, each of the two or more next-order users 220 spectrally senses the applied channel a plurality of times within each time period for a plurality of time periods to generate channel usage state information having a predetermined energy value. In other words, each of the two or more next-order users 220 performs spectral sensing of an applied channel a plurality of times within one time period, and repeats such an operation for a plurality of time periods to generate channel usage information. The channel usage state information generated as described above is transmitted to the cooperative spectrum sensing device 230.

The cooperative spectrum sensing device 230 that receives the channel usage status information from two or more next-order users 220 performs a fitness check for each next-order users 220 through the detector 232 to determine whether the corresponding next-order user is a malicious user. Determine.

First, the detector 232 generates the summed energy values by summing the energy values of channel usage state information generated by the next-order user 220 for each time period.

,

) 중에서 어느 하나의 경우에 따라 표현될 수 있다.
At this time, in each time period, it may be sensed that there is a priority user or that there is no priority user. Therefore, the sum of the energy values is two cases (1)

,

) May be expressed according to any one case.

는 k번째 시간 주기에서 인가 채널이 우선순위 사용자에 의해 사용되지 않는 것으로 센싱된 경우를 의미하고,

는 k번째 시간 주기에서 인가 채널이 우선순위 사용자에 의해 사용되는 것으로 센싱된 경우를 각각 의미한다. here,

Means when the authorized channel is sensed not used by the priority user in the kth time period,

Denotes a case where the authorization channel is sensed to be used by the priority user in the k-th time period.

는 i번째 차순위 사용자가 k번째 시간 주기에서 생성한 채널 사용상태 정보들의 합(즉, 지역 테스트 통계값(Local Test Statistics)),

는 k번째 시간 주기가 시작되는 시점,

은 k번째 시간 주기 내에서의 n번째 스펙트럼 센싱 시 우선순위 사용자와 i번째 차순위 사용자 사이의 채널의 이득(Channel Gain),

는 k번째 시간 주기 내에서의 n번째 스펙트럼 센싱 시 우선순위 사용자와 i번째 차순위 사용자 사이의 채널에서의 잡음,

은 k번째 시간 주기 내에서의 n번째 스펙트럼 센싱 시 우선순위 사용자로부터 전송된 신호를 각각 의미한다.And,

Is the sum of channel usage information generated by the i th order user in the k th time period (ie, Local Test Statistics),

Is when the k th time period begins,

Is the gain of the channel between the priority user and the i-th order user during nth spectrum sensing within the kth time period,

Is the noise in the channel between the priority user and the i-th order user during nth spectrum sensing within the kth time period,

Denotes a signal transmitted from a priority user during n-th spectrum sensing within a k-th time period.

이 단위 전력(Unit Power)을 가지는 PSK(Phase Shift Keying) 변조 신호이고,

이 독립적인 레일리 페이딩(Independent Rayleigh Fading) 채널의 이득이며,

이 분산

을 가지는 복소 가산성 백색 가우시안 잡음(Complex-valued AWGN)인 경우, 아래의 수학식 2와 같은 관계가 성립한다.
if,

PSK (Phase Shift Keying) modulated signal having a unit power (Unit Power),

The gain of this independent Rayleigh Fading channel,

This dispersion

In the case of complex additive white Gaussian noise (Complex-valued AWGN) having a relation, the following equation 2 holds.

는 아래의 수학식 3에 도시된 바와 같이 가우시안 랜덤 변수에 근접한다.
Also, according to the Central Limit Theorem, if N is large enough (for example, if N has a value of 10 or more),

Is close to a Gaussian random variable as shown in Equation 3 below.

)를 정의한다.
On the other hand, to determine which channel usage model of the channel usage status information for the next-order user 220 is more similar to the channel usage model for non-malicious users and the channel usage model for malicious users, the detection unit ( 232 is an empirical distribution function (Equation 4 below)

).

는 지시 함수(Indication Function)로서,

가 참(true)인 경우 1의 값을 가지고,

가 거짓(false)인 경우 0의 값을 가진다. here,

Is an indication function,

Has a value of 1 if is true,

Has a value of 0 if is false.

는 k가 커질수록(

) 악성 사용자에 대한 채널 사용상태 모델(

)로 수렴한다. 반대로, 만약 i번째 차순위 사용자가 비악성 사용자인 경우

는 k가 커질수록(

) 비악성 사용자에 대한 채널 사용상태 모델(

)로 수렴한다.If the i-th rank user is a malicious user

As k increases (

) Channel usage model for malicious users (

Converge) Conversely, if the ith next user is a non-malicious user

As k increases (

) Channel usage model for non-malicious users (

Converge)

)와 인가 채널이 우선순위 사용자에 의해 사용되는 것으로 센싱된 경우(

) 사이의 채널 사용상태 정보에 대한 보고 빈도(Report Frequency)는 우선순위 사용자가 인가 채널을 사용하는 기간과 사용하지 않는 기간 사이의 비율과 동일하게 된다. 따라서,

는 아래의 수학식 5와 같이 표현될 수 있다.
Here, since the non-malicious user generates and transmits the channel usage status information which has not been manipulated as described above, when the authorized channel is sensed not to be used by the priority user (

) And the authorized channel are sensed to be used by the priority user (

The report frequency of channel usage status information between the two channels is equal to the ratio between the period in which the priority user uses the authorized channel and the period in which it is not used. therefore,

May be expressed as Equation 5 below.

는 인가 채널이 우선순위 사용자에 의해 사용되지 않을 확률,

는 인가 채널이 우선순위 사용자에 의해 사용될 확률,

는 인가 채널이 우선순위 사용자에 의해 사용되지 않는 것으로 센싱된 경우의 경험적 분포 함수,

는 인가 채널이 우선순위 사용자에 의해 사용되는 것으로 센싱된 경우의 경험적 분포 함수를 각각 의미한다. here,

Is the probability that the authorization channel is not used by the priority user,

Is the probability that the authorization channel will be used by the priority user,

Is the empirical distribution function when the authorized channel is sensed not to be used by the priority user,

Denotes the empirical distribution function when the authorized channel is sensed to be used by the priority user, respectively.

) 의 채널 사용상태 정보를 협력 스펙트럼 센싱 장치(230)로 보고하므로,

는 아래의 수학식 6과 같이 표현될 수 있다.
And, most of the non-malicious users, if the authorization channel is used by the priority user (

Since the channel usage status information of) to the cooperative spectrum sensing device 230,

May be expressed as Equation 6 below.

In such a case, according to an embodiment of the present invention, the detector 232 may determine whether each next-order user 220 is a non-malicious user or a malicious user by using an Anderson-Darling technique.

가 악성 사용자에 대한 채널 사용상태 모델에 근접하는지를 판단한다.
The Anderson-Darling (AD) technique is a goodness-of-fit test with high sensitivity and low throughput, and the following equation 7 is used for each next-order user 220 using Equation 7 below.

Determines whether the model is close to the channel usage model for malicious users.

는 앤더슨-달링 통계(AD statistic) 함수를 의미하고,

는 k개의

중 j번재로 작은 값을 의미한다. here,

Means the Anderson-Darling statistical function,

K

It means the smallest value of j.

는 i번째 차순위 사용자가 얼마나 악성 사용자에 가까운지를 판단하기 위한 것이므로, 검출부(232)는

와 컷 오프 임계값(Cut-off Threshold)인

를 비교한다. 만약,

이

보다 작다면, i번째 차순위 사용자는 악성 사용자로 판별된다.

Is for determining how close the i-th rank user is to the malicious user, the detection unit 232

With cut-off threshold

. if,

this

If smaller, the i-th rank user is determined to be a malicious user.

는 악성 사용자에 대한 컷 오프 확률(즉, 악성 사용자가 검출되어 배제될 확률)인

이 목적값인

보다 크도록 유지하는 값을 가지며, 이는 아래의 수학식 8과 같이 표현될 수 있다.
At this time,

Is the probability of the cutoff for the malicious user (i.e. the probability that the malicious user has been detected and excluded)

Is the target value

It has a value to be kept larger than, which can be expressed as Equation 8 below.

의 분포를 이용하여 수행될 수 있으며, 이는 아래의 수학식 9와 같이 표현될 수 있다.
The calculation of Equation 8 above

It may be performed using the distribution of, which may be expressed as Equation 9 below.

On the other hand, due to the fast convergence property (Fast Convergence Property), Equation 9 may have an accurate convergence value when k has a value of 5 or more.

)에 대한 컷 오프 임계값(

)을 산출할 수 있다. 일례로서, 목적 컷 오프 확률(

)에 대한 컷 오프 임계값(

)은 아래의 표 1과 같을 수 있다.Then, the detection unit 232 uses the above equation (9) to the target cutoff probability (

Cutoff threshold for

) Can be calculated. As an example, the target cutoff probability (

Cutoff threshold for

) May be as shown in Table 1 below.

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

0.346 0.448 0.546 0.652 0.774 0.923 1.120 1.408 1.933

4 and 5 illustrate simulation results of detecting malicious users using the above-described fitness test technique.

)을 0.2로, 차순위 사용자들(220)의 개수를 30개로, 악성 사용자(항상 인가 채널이 사용중인 것으로 보고함)의 개수를 5개로, 하나의 시간 주기 내에서의 센싱 횟수를 50회로 설정하였다. In this simulation, the probability that a priority user is using an authorization channel (

) Is set to 0.2, the number of next-order users 220 to 30, the number of malicious users (always reported to be in use by the authorized channel) to 5, and the number of sensing in one time period is set to 50 times. .

)과 비악성 사용자의 컷 오프 확률(

) 사이의 관계를 도시하고 있다. 여기서, OD는 앞서 설명한 종래의 이상값 검출 기법에 따른 측정값을 의미하고, GF는 본 발명에 따른 측정값을 의미한다. First, in FIG. 4, the cutoff probability of the malicious user according to the SNR values of various priority users (

) And the probability of cutoff for non-malignant users (

) Shows the relationship between Here, OD means a measured value according to the conventional outlier detection technique described above, and GF means a measured value according to the present invention.

4, it can be seen that the measured value according to the present invention is always smaller than the measured value according to the conventional outlier detection technique. In other words, when using the cooperative spectrum sensing device 230 according to the present invention, it is possible to more accurately detect malicious users

)과 비악성 사용자의 컷 오프 확률(

) 사이의 관계를 도시하고 있다.Next, in FIG. 5, the cutoff probability of the malicious user according to the number of time periods k for spectrum sensing (

) And the probability of cutoff for non-malignant users (

) Shows the relationship between

Referring to FIG. 5, when the cooperative spectrum sensing device 230 according to the present invention is used, a malicious user may be detected more accurately than using a conventional outlier detection technique, and the detection performance is higher as the number of time periods increases. It can be confirmed that it is accurate.

FIG. 6 is a graph illustrating a comparison of a malicious user detection probability and an error notification probability in the case of using the conventional outlier detection technique and the cooperative spectrum sensing device 230 according to the present invention.

Referring to FIG. 6, the conventional outlier detection technique detects a malicious user using an outlier every time, and thus does not change the probability of error notification even if the number of sensing increases, but the cooperative spectrum sensing device 230 according to the present invention 230. ) Detects malicious users using the probability distribution of the outliers, so that the probability of error notification decreases as the number of sensing increases.

7 is a flowchart illustrating the overall flow of the cooperative spectrum sensing method according to an embodiment of the present invention. Hereinafter, a process performed for each step will be described.

First, in step S710, two or more next-order users who want to use the channel applied to the priority user receive the usage state information (channel usage state information) of the authorized channel obtained by spectral sensing of the authorization channel for a predetermined time. Received from the above next-order users.

Next, in step S720, the distribution of channel usage state information for a predetermined time is analyzed for each of the at least two next-order users to detect at least one malicious user among the at least two next-order users.

Finally, in step S730, the channel is selected by the priority user using the remaining channel usage information except for channel usage information received from one or more malicious users among channel usage information received from two or more next-order users. Determine if it is being used.

According to an embodiment of the present invention, channel usage state information may include an energy value of a signal detected in the channel.

In this case, according to an embodiment of the present invention, in step S720, channel usage state information having an energy value greater than a reference energy value among channel usage state information transmitted by one of the next-order users among two or more next-order users. If the ratio is greater than or equal to the threshold ratio than the ratio of the channel usage state information having an energy value smaller than the reference energy value, one of the next-order users may be detected as a malicious user.

In addition, according to an embodiment of the present invention, by comparing the channel usage model for non-malicious users, the channel usage model for malicious users and the analysis results of the distribution of channel usage information for each of the two or more next-order users One or more malicious users may be detected among the two or more next-order users. In this case, the channel usage model for the non malicious user has a distribution in which the ratio of channel usage information having an energy value greater than the reference energy value is greater than the threshold ratio than the ratio of channel usage information information having an energy value less than the reference energy value. It can have

Embodiments of the cooperative spectrum sensing method according to the present invention have been described so far, and the configuration of the cooperative spectrum sensing device 230 described above with reference to FIG. 2 is also applicable to the present embodiment. Hereinafter, a detailed description will be omitted.

In addition, embodiments of the present invention may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Examples of program instructions, such as magneto-optical and ROM, RAM, flash memory and the like, can be executed by a computer using an interpreter or the like, as well as machine code, Includes a high-level language code. The hardware devices described above may be configured to operate as one or more software modules to perform operations of one embodiment of the present invention, and vice versa.

As described above, the present invention has been described with reference to particular embodiments, such as specific elements, and limited embodiments and drawings. However, it should be understood that the present invention is not limited to the above- Various modifications and variations may be made thereto by those skilled in the art to which the present invention pertains. Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

Claims (13)

Receive usage status information (channel usage status information) of the channel obtained by spectral sensing of the channel multiple times for a predetermined time by two or more next-order users who want to use the channel authorized to the priority user from the second or more next-order users. A receiving unit;
A detector configured to analyze the distribution of the channel usage state information for the predetermined time for each of the at least two next-order users and detect at least one malicious user among the at least two next-order users; And
It is determined whether the channel is used by the priority user by using the remaining channel usage information except for the channel usage information received from the at least one malicious user among the channel usage status information received from the at least two next-order users. Including a judgment unit,
The detector may be configured to generate an energy value in which a ratio of channel use state information having an energy value greater than a reference energy value among the channel use state information transmitted by any one of the second or more next order users is less than the reference energy value. The cooperative spectrum sensing device, characterized in that the detection of any one of the next priority user as a malicious user when the branch is greater than the threshold ratio than the ratio of the channel use state information. The method of claim 1,
The spectral sensing is spectral sensing based on energy detection,
The channel usage state information includes an energy value of the signal detected in the channel. delete Receive usage status information (channel usage status information) of the channel obtained by spectral sensing of the channel multiple times for a predetermined time by two or more next-order users who want to use the channel authorized to the priority user from the second or more next-order users. A receiving unit;
A detector configured to analyze the distribution of the channel usage state information for the predetermined time for each of the at least two next-order users and detect at least one malicious user among the at least two next-order users; And
It is determined whether the channel is used by the priority user by using the remaining channel usage information except for the channel usage information received from the at least one malicious user among the channel usage status information received from the at least two next-order users. Including a judgment unit,
The detection unit compares a channel usage model for a malicious user, a channel usage model for a malicious user, and an analysis result of distribution of channel usage information for each of the two or more next-order users, and compares the results of the analysis. Cooperative spectrum sensing device, characterized in that for detecting the one or more malicious users. 5. The method of claim 4,
The channel usage state model for the non-malignant user has a distribution in which the ratio of channel usage state information having an energy value greater than a reference energy value is greater than the ratio of the channel usage state information having an energy value less than the reference energy value. Cooperative spectrum sensing device characterized by having. 5. The method of claim 4,
The detector uses a goodness of fit test technique to distribute the channel usage state information for each of the two or more next-order users to the channel usage state model for the non-malicious user and the channel usage state for the malicious user. A cooperative spectrum sensing device, characterized in that it is determined which channel usage state model among the models. The method according to claim 6,
The suitability check technique is a cooperative spectrum sensing device, characterized in that the Anderson-Darling technique. Receive usage status information (channel usage status information) of the channel obtained by spectral sensing of the channel multiple times for a predetermined time by two or more next-order users who want to use the channel authorized to the priority user from the second or more next-order users. Making;
Analyzing the distribution of the channel usage state information for the predetermined time for each of the at least two next-order users and detecting at least one malicious user from the at least two next-order users; And
It is determined whether the channel is used by the priority user by using the remaining channel usage information except for the channel usage information received from the at least one malicious user among the channel usage status information received from the at least two next-order users. Including the steps of:
The detecting may include energy of a channel usage state information having an energy value greater than a reference energy value among the channel usage state information transmitted by one of the second or more next-order users. And detecting one of the next-ranked users as a malicious user when the ratio is greater than or equal to a ratio of the channel usage state information having a value. 9. The method of claim 8,
The spectral sensing is spectral sensing based on energy detection,
The channel usage state information includes the energy value of the signal sensed in the channel. delete Receive usage status information (channel usage status information) of the channel obtained by spectral sensing of the channel multiple times for a predetermined time by two or more next-order users who want to use the channel authorized to the priority user from the second or more next-order users. Making;
Analyzing the distribution of the channel usage state information for the predetermined time for each of the at least two next-order users and detecting at least one malicious user from the at least two next-order users; And
It is determined whether the channel is used by the priority user by using the remaining channel usage information except for the channel usage information received from the at least one malicious user among the channel usage status information received from the at least two next-order users. Including the steps of:
The detecting may be performed by comparing a channel usage model for a non-malicious user, a channel usage model for a malicious user, and an analysis result of distribution of channel usage information for each of the at least two next-order users. Cooperative spectrum sensing method characterized in that for detecting the one or more malicious users. 12. The method of claim 11,
The channel usage state model for the non-malignant user has a distribution in which the ratio of channel usage state information having an energy value greater than a reference energy value is greater than the ratio of the channel usage state information having an energy value less than the reference energy value. Cooperative spectrum sensing method characterized by having. A computer-readable recording medium having recorded thereon a program for performing the method of any one of claims 8, 9 and 11-12.

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