JP6892646B2 - A judgment device, a program to be executed by a computer, and a computer-readable recording medium on which the program is recorded. - Google Patents

Description

The present invention relates to a determination device, a program to be executed by a computer, and a computer-readable recording medium on which the program is recorded.

In the 5th generation mobile communication system, it is necessary to secure a further frequency band in order to satisfy various demands for communication performance. On the other hand, a technique for sharing a frequency that is not used in a local place or time is attracting attention (Non-Patent Document 1).

Then, a frequency sharing system for a frequency of 6 GHz or less suitable for mobile communication is being studied. In this system, the power values for each time, place, and frequency acquired by monitoring are stored in a database, and various frequencies are shared by allocating frequencies that are not used by the primary user according to the application of the secondary user. (Non-Patent Document 2).

In addition, we actually measured the frequency spectrum in urban areas and confirmed frequencies that were not used depending on the time and place (Non-Patent Document 3).

Ministry of Internal Affairs and Communications, “Radio Policy 2020 Roundtable Report”, June 2016. Matsuno, et al., "Efforts for frequency sharing between different wireless systems in 5th generation mobile communication systems," Confidential Techniques, RCS116, Oct.2016. Waka, et al., “Broadband spectrum measurement assuming frequency sharing,” Shingaku Sodai, B-16-20, Sep. 2016.

In a frequency sharing system, it is necessary not to interfere with users (existing systems) who have already been assigned frequencies.

Then, in order to prevent interference, the power value of the radio wave of the frequency is observed at a place where the frequency is shared, and the frequency is shared after confirming that the existing system is not used.

However, when determining whether or not the existing system is used using the power value, even if out-of-band radiation (spurious) is observed, it is determined that the existing system is used, so the frequency band that can be shared is possible. There is a problem that the width becomes narrow.

Therefore, according to the embodiment of the present invention, there is provided a determination device capable of widening the frequency bandwidth capable of frequency sharing.

Further, according to an embodiment of the present invention, a program for causing a computer to execute an extension of a frequency bandwidth capable of frequency sharing is provided.

Further, according to an embodiment of the present invention, there is provided a computer-readable recording medium on which a program for causing a computer to execute an extension of a frequency bandwidth capable of frequency sharing is recorded.

(Structure 1)
According to the embodiment of the present invention, the determination device includes selection means, detection means, and determination means. The selection means selects a frequency. The detecting means detects the power value of the radio wave having the frequency selected by the selecting means. When the power value detected by the detection means is equal to or less than the threshold value, the determination means includes a first determination process for determining that the existing system, which is a radio system of a user who has already been assigned a frequency, is not used, and detection. When the power value detected by the means is larger than the threshold value, a second determination process for determining whether the radio wave is out-of-band radiation or the use of an existing system is performed based on the presence or absence of a correlated frequency.

The determination device according to the embodiment of the present invention determines that the existing system is not used when the power value is equal to or less than the threshold value. Further, when the power value is larger than the threshold value, the determination device determines whether the radio wave is out-of-band radiation or the use of an existing system depending on the presence or absence of a correlated frequency. As a result, when it is determined that the radio wave is out-of-band radiation, it is possible to perform wireless communication using the frequency of out-of-band radiation.

Therefore, it is possible to widen the frequency bandwidth that allows frequency sharing.

(Structure 2)
In the first configuration, in the second determination process, the determination means determines that the radio wave is out-of-band radiation when there is a correlated frequency, and determines that the existing system is used when there is no correlated frequency. To do.

According to the configuration 2, when there is a correlation between the frequency used for transmission and the frequency other than the frequency used for transmission, it is determined that the radio wave is out-of-band radiation, and the frequency other than the frequency used for transmission and the frequency used for transmission are not included. When there is no correlation with the frequency of, it is judged that the existing system is used.

Therefore, by obtaining the correlation between the frequency used for transmission and the frequency other than the frequency used for transmission, it is possible to easily determine whether or not the existing system is used.

(Structure 3)
In the configuration 2, the determination means uses the existing system when it is determined in the second determination process that the radio wave is out-of-band radiation and there is no correlation between the radio wave and the signal generation model of the primary user. When it is determined that there is no radio wave and there is a correlation between the radio wave and the signal generation model of the primary user, it is determined that the existing system is used.

According to the configuration 3, when it is determined that the radio wave is out-of-band radiation, it is further determined whether or not there is a correlation between the radio wave and the signal generation model of the primary user. Then, when there is no correlation between the radio wave and the signal generation model of the primary user, it is determined that the existing system is not used, and when there is a correlation between the radio wave and the signal generation model of the primary user, the existing system is used. Is determined to be present.

As a result, it is possible to further determine whether or not the existing system is used at the frequency determined to be out-of-band radiation, and to determine from the frequency of out-of-band radiation the frequency at which the existing system is not used.

Therefore, it is possible to accurately widen the frequency bandwidth that allows frequency sharing.

(Structure 4)
In configuration 3, the determination device further includes signal generating means. The signal generating means generates the frequency of the radio wave according to the Poisson process, generates the duration of the radio wave according to the exponential distribution, and arbitrary power selected from the range of the power value defined by the minimum value and the maximum value of the power of the radio wave. A value is generated as a signal strength, and a radio wave having a generated frequency, duration, and signal strength is generated as a radio wave of a primary user. Then, when there is no correlation between the first radio wave generated by the signal generating means and the second radio wave having the power value, the determination means determines that the existing system is not used, and determines that the existing system is not used, and the first radio wave and the second radio wave are used. When there is a correlation with the radio wave of 2, it is determined that the existing system is used.

According to the configuration 4, the frequency of the radio wave is generated according to the Poisson process, and the duration of the radio wave is generated by the exponential distribution. Then, a radio wave having the generated frequency and duration is generated as a radio wave of the primary user.

Therefore, the traffic model can be applied to generate radio waves. As a result, it is possible to easily determine whether or not the existing system is used based on the presence or absence of the correlation between the first radio wave and the second radio wave.

(Structure 5)
In the configuration 4, the signal generating means has a radio wave duration corrected to be close to the measured radio wave duration and a unit time corrected to be close to the measured average wave number per unit time. The first radio wave is generated using the average wave number per hit.

According to the configuration 6, it is possible to generate a first radio wave having a duration close to the measured duration of the radio wave and an average wave number per unit time close to the measured average number of radio waves per unit time. it can.
(Structure 6)
In the configuration 5, the signal generating means has a first duration such that the first duration obtained by (measured radio wave duration) × first correction coefficient is close to the measured radio wave duration. While determining the correction coefficient, the first average number of elementary waves obtained by (measured average number of elementary waves per unit time) x second correction coefficient becomes close to the measured average number of elementary waves per unit time. The second correction coefficient was determined in this way, and the second duration obtained by multiplying the determined first correction coefficient by the measured duration of the radio wave and the determined second correction coefficient were actually measured. The first radio wave is generated by using the second average number of elementary waves obtained by multiplying the average number of elementary waves per unit time.

According to the configuration 6, when the probability function (statistical value assuming the number of wireless samples) is obtained from the measured data consisting of a finite number of samples, the bias generated in the samples can be suppressed and the first radio wave can be generated. ..

(Structure 7)
In any of the configurations 3 to 6, the determination means determines whether or not there is a correlation between the radio wave and the signal generation model of the primary user by using Pearson's product moment correlation coefficient.

According to Configuration 7, by using Pearson's product moment correlation coefficient, it is determined that there is a correlation when the correlation coefficient is greater than 0.5, and strong when the correlation coefficient is greater than 0.8. It is determined that there is a correlation.

Therefore, it is possible to easily determine whether or not there is a correlation between the radio wave and the signal generation model of the primary user. In addition, it is possible to know the degree of correlation between the radio wave and the signal generation model of the primary user.

(Structure 8)
In any of configurations 2 to 7, the determination means determines the presence or absence of correlated frequencies using Pearson's product moment correlation coefficient.

According to Configuration 8, by using Pearson's product moment correlation coefficient, it is determined that there is a correlation when the correlation coefficient is greater than 0.5, and strong when the correlation coefficient is greater than 0.8. It is determined that there is a correlation.

Therefore, it is possible to easily determine whether or not there is a correlation between the frequency used for transmission and a frequency other than the frequency used for transmission. In addition, the degree of correlation between the frequency used for transmission and the frequency other than the frequency used for transmission can be known.

(Structure 9)
Further, according to the embodiment of the present invention, the program detects the power value of the radio wave having the frequency selected in the first step by the selection means and the detection means in the first step. When the power value detected in the second step is equal to or less than the threshold value, the determination means determines that the existing system, which is the radio system of the user who has already been assigned the frequency, is not used. When the power value detected by the detection means is larger than the threshold value, it is determined whether the radio wave is out-of-band radiation or the use of the existing system based on the presence or absence of the frequency having a correlation. This is a program for causing a computer to execute a second determination process and a third step of performing the determination process.

By letting the computer execute the program, when the power value is equal to or less than the threshold value, it is determined that the existing system is not used. Further, when the power value is larger than the threshold value, it is determined whether the radio wave is out-of-band radiation or the use of an existing system depending on the presence or absence of a correlated frequency. As a result, when it is determined that the radio wave is out-of-band radiation, it is possible to perform wireless communication using the frequency of out-of-band radiation.

Therefore, it is possible to widen the frequency bandwidth that allows frequency sharing.

(Structure 10)
In the configuration 9, the determination means determines that the radio wave is out-of-band radiation when there is a correlated frequency in the second determination process of the third step, and when there is no correlated frequency, the determination means of the existing system. Judge that there is use.

By letting the computer execute the program, when there is a correlation between the frequency used for transmission and the frequency other than the frequency used for transmission, it is determined that the radio wave is out-of-band radiation, and the frequency used for transmission and the frequency used for transmission are used. When there is no correlation with frequencies other than the frequency to be used, it is determined that the existing system is used.

Therefore, by obtaining the correlation between the frequency used for transmission and the frequency other than the frequency used for transmission, it is possible to easily determine whether or not the existing system is used.

(Structure 11)
In the configuration 10, when the determination means determines that the radio wave is out-of-band radiation in the second determination process of the third step, and there is no correlation between the radio wave and the signal generation model of the primary user, It is determined that the existing system is not used, and when there is a correlation between the radio wave and the signal generation model of the primary user, it is determined that the existing system is used.

When it is determined that the radio wave is out-of-band radiation by causing the computer to execute the program, it is further determined whether or not there is a correlation between the radio wave and the signal generation model of the primary user. Then, when there is no correlation between the radio wave and the signal generation model of the primary user, it is determined that the existing system is not used, and when there is a correlation between the radio wave and the signal generation model of the primary user, the existing system is used. Is determined to be present.

As a result, it is possible to further determine whether or not the existing system is used at the frequency determined to be out-of-band radiation, and to determine from the frequency of out-of-band radiation the frequency at which the existing system is not used.

Therefore, it is possible to accurately widen the frequency bandwidth that allows frequency sharing.

(Structure 12)
In configuration 11, the program is such that the signal generating means generates the frequency of the radio wave according to the Poisson process, generates the duration of the radio wave according to the exponential distribution, and the power value defined by the minimum value and the maximum value of the power of the radio wave. An arbitrary power value selected from the range is generated as a signal strength, and a fourth step of generating a radio wave having the generated frequency, duration and signal strength as a radio wave of a primary user is further executed by a computer. Then, in the third step, the determination means determines that the existing system is not used when there is no correlation between the first radio wave generated in the fourth step and the second radio wave having the power value. When there is a correlation between the first radio wave and the second radio wave, it is determined that the existing system is used.

By letting the computer execute the program, the frequency of the radio wave is generated according to the Poisson process, and the duration of the radio wave is generated by the exponential distribution. Then, a radio wave having the generated frequency and duration is generated as a radio wave of the primary user.

Therefore, the traffic model can be applied to generate radio waves. As a result, it is possible to easily determine whether or not the existing system is used based on the presence or absence of the correlation between the first radio wave and the second radio wave.

(Structure 13)
In the configuration 12, the signal generating means is set to be close to the duration of the radio wave corrected so as to be close to the duration of the measured radio wave in the fourth step and the average wave number per unit time actually measured. The first radio wave is generated using the average wave number per unit time corrected to.

By letting the computer execute the program, a first radio wave having a duration close to the measured duration of the radio wave and an average prime wave number per unit time close to the measured average prime wave number per unit time is generated. can do.

(Structure 14)
In the fourth step, in the fourth step, in the fourth step, the signal generation means has the first duration obtained by (measured radio wave duration) × first correction coefficient close to the measured radio wave duration. The first correction coefficient is determined so as to be (the average number of elementary waves per unit time actually measured) × the first average number of elementary waves obtained by the second correction coefficient is the measured number of elementary waves per unit time. The first sub-step of determining the second correction coefficient so as to be close to the average number of elementary waves and the signal generating means obtained by multiplying the determined first correction coefficient by the duration of the actually measured radio wave. The first radio wave is generated by using the second duration and the second average number of elementary waves obtained by multiplying the determined second correction coefficient by the measured average number of elementary waves per unit time. Includes a second substep.

By letting a computer execute the program, the bias that occurs in the sample when obtaining the probability function (statistical value assuming the number of wireless samples) from the measured data consisting of a finite number of samples is suppressed and the first radio wave is generated. be able to.

(Structure 15)
In any of configurations 11 to 14, the determination means determines in the third step whether or not there is a correlation between the radio wave and the signal generation model of the primary user using Pearson's product moment correlation coefficient.

By letting the computer execute the program, when the correlation coefficient is larger than 0.5, it is determined that there is a correlation, and when the correlation coefficient is larger than 0.8, it is determined that there is a strong correlation.

Therefore, it is possible to easily determine whether or not there is a correlation between the radio wave and the signal generation model of the primary user. In addition, it is possible to know the degree of correlation between the radio wave and the signal generation model of the primary user.

(Structure 16)
In any of configurations 10 to 15, the determination means determines in the third step the presence or absence of correlated frequencies using Pearson's product moment correlation coefficient.

By letting the computer execute the program, when the correlation coefficient is larger than 0.5, it is determined that there is a correlation, and when the correlation coefficient is larger than 0.8, it is determined that there is a strong correlation.

Therefore, it is possible to easily determine whether or not there is a correlation between the frequency used for transmission and a frequency other than the frequency used for transmission. In addition, the degree of correlation between the frequency used for transmission and the frequency other than the frequency used for transmission can be known.

(Structure 17)
Further, according to an embodiment of the present invention, the recording medium is a computer-readable recording medium on which the program according to any one of configurations 9 to 16 is recorded.

It is possible to widen the frequency bandwidth that allows frequency sharing.

It is the schematic of the determination apparatus according to Embodiment 1 of this invention. It is a figure which shows the correlation coefficient calculated by using the formula (1). It is a flowchart for demonstrating operation of the determination apparatus shown in FIG. It is the schematic of the determination device according to Embodiment 2. It is a conceptual diagram of a bare wave. It is a conceptual diagram which shows the distribution of a frequency f _n. It is a flowchart for demonstrating operation of the signal generating means shown in FIG. It is a flowchart for demonstrating operation of the determination apparatus shown in FIG. It is the schematic of the determination device according to Embodiment 3. It is a figure which shows the relationship between the measured received power and a frequency. It is a figure which shows the actual measurement example of a wide band spectrum. It is a flowchart for demonstrating operation of the signal generating means shown in FIG. It is a figure which shows the comparison between the measured value and the calculated value of the duration, the average element wave number and the spatial density of an element wave. It is a flowchart for demonstrating operation of the determination apparatus shown in FIG. It is the schematic of the terminal device which includes the determination device shown in FIG. It is a schematic diagram of the terminal device provided with the determination device shown in FIG. FIG. 5 is a schematic view of a terminal device including the determination device shown in FIG.

Embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals, and the description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a schematic view of a determination device according to the first embodiment of the present invention. With reference to FIG. 1, the determination device 10 according to the first embodiment of the present invention includes an antenna 11, a receiving means 12, a selecting means 13, a signal processing means 14, a detecting means 15, a calculation means 16, and the like. The determination means 17 is provided.

The receiving means 12 holds in advance the frequency band BW used in the frequency sharing system. The receiving means 12 receives the frequency f _U (center frequency) and the bandwidth ΔBW from the selecting means 13. Then, the receiving means 12 receives _{the radio wave wv_U whose center frequency is the frequency f U} and whose bandwidth is ΔBW via the antenna 11, and the received radio wave wv_U is sent to the signal processing means 14 and the detecting means 15. Output. The receiving unit 12 is the frequency _{f EX} other than the center frequency is the frequency _{f U,} and, a radio wv_EX bandwidth is ΔBW received via the antenna 11, the signal processing means the electric wave wv_EX that the received 14 Output to.

The selection means 13 holds the frequency band BW in advance, selects the _{frequency f U from the frequency band BW, and outputs the selected frequency f U} and the bandwidth ΔBW to the receiving means 12.

The signal processing means 14 receives radio waves wv_U and wv_EX from the receiving means 12. Then, the signal processing means 14 performs reception processing of the radio wave wv_U and generates a time response x (t) of the received signal. Further, the signal processing means 14 performs reception processing of the radio wave wv_EX and generates a time response y (t) of the received signal. Then, the signal processing means 14 outputs the time responses x (t) and y (t) of the received signal to the calculation means 16.

The detecting means 15 receives the radio wave wv_U from the receiving means 12, and detects the power value P of the received radio wave wv_U. Then, the detection means 15 outputs the power value P to the determination means 17.

The arithmetic means 16 receives the time response x (t), y (t) of the received signal from the signal processing means 14, and based on the time response x (t), y (t) of the received signal, the following equation The correlation coefficient r between the frequency f _U and the frequency f _{EX is calculated by.}

In the equation (1), x and y with a bar above are expected values of the time response x (t) and y (t) of the received signal, respectively. Further, T is the number of time samples.

The correlation coefficient r obtained by the equation (1) is Pearson's product-moment correlation coefficient, and can take a value in the range of 0 ≦ r ≦ 1.

When Pearson's product-moment correlation coefficient is used, when the correlation coefficient r calculated by the equation (1) is larger than 0.5, the correlation between the time response x (t) and the time response y (t) is When it is determined that there is, and the correlation coefficient r is larger than 0.8, it is determined that there is a strong correlation between the time response x (t) and the time response y (t).

Therefore, by using Pearson's product moment correlation coefficient, the correlation between the time response x (t) and the time response y (t) can be easily determined. In addition, the degree of correlation between the time response x (t) and the time response y (t) can be known.

Time response y of the received signal (t) in the frequency band BW, since the time response of the radio wave of the received signal having a frequency _{f U} except for all frequencies _{f EX} (bandwidth ΔBW), y (t) = y ₁ (t), y ₂ (t), ..., y _N (t) (N = BW / ΔBW).

Therefore, the arithmetic means 16 uses the equation (1) to _{correlate x (t) with each of y 1} (t), y ₂ (t), ..., Y _N (t). Calculate ₁ , r ₂ , ..., R _N.

Computing means 16, when calculating a correlation coefficient _r n (n = 1 to N) by the formula (1), and outputs the correlation coefficient _{r n} that the operation to the determination means 17.

Determination means 17 receives the power values P from the detection means 15 receives the correlation coefficient _{r n} from the arithmetic unit 16. The determination unit 17 determines, based on the power value P and the correlation coefficient r _n, by the following method, the presence and absence of the out-of-band radiation utilization of existing systems.

The determination means 17 determines whether or not the power value P is equal to or less than the threshold value P_th. The threshold value P_th is, for example, a value about 5 dB higher than the noise floor seen in the measurement region. Then, when the determination means 17 determines that the power value P is equal to or less than the threshold value P_th, it determines that the existing system is not used.

When the determination means 17 determines that the power value P is larger than the threshold value P_th, it further determines whether or not there is a frequency having a correlation.

More specifically, the determination means 17, by determining whether the correlation coefficient r _n greater than the threshold r_th, further determines whether the frequency that correlates there. The threshold r_th is set to, for example, 0.5.

The determination unit 17 is when the correlation coefficient r _n was determined to be greater than the threshold r_th (i.e., when it is determined that the frequency with correlation there), radio wv_EX out-of-band radiation received (spurious) Is determined.

On the other hand, the determination means 17, when it is determined that the correlation coefficient r _n is less than or equal to the threshold r_th (i.e., when it is determined that there is no frequency that correlates), it is determined that there use of existing systems.

The determination means 17 determines whether or not the existing system is used and whether or not there is out-of-band radiation by the method described above, and outputs the determination result.

Figure 2 is a graph showing the correlation coefficient r _n calculated using equation (1). (A) of FIG. 2 shows the correlation coefficient _{r n} in the measurement location A, in FIG. 2 (b) shows the correlation coefficient _{r n} in the measurement location B.

With reference to FIG. 2, at location A, only the autocorrelation is "1" and the correlation between the other frequencies is approximately "0" (see (a) in FIG. 2).

On the other hand, in place B, a high correlation having a width of about 20 MHz appears regularly. Therefore, it is highly possible that the radiation is out of band from the same wave source. Moreover, since the correlation is high over the entire band, it was confirmed that there is a high possibility that the wave source is a frequency lower than the measurement band. Here, the high correlation refers to a correlation coefficient r _n greater than the threshold r_th.

Thus, by using the correlation coefficient r _n, it is possible to determine whether the out-of-band radiation.

FIG. 3 is a flowchart for explaining the operation of the determination device 10 shown in FIG. Referring to FIG. 3, a series of operations is started, the selection means 13 selects the frequency f _U of the used target from the frequency band BW (step S1), the the selected frequency f _U to a receiving means 12 Output.

The receiving means 12 receives the frequency f _U from the selecting means 13, receives the _{radio wave wv_U having the received frequency f U} via the antenna 11, and outputs the received radio wave wv_U to the signal processing means 14 and the detecting means 15. To do.

The detecting means 15 receives the radio wave wv_U from the receiving means 12, and detects the power value P of the received radio wave wv_U (step S2). Then, the detection means 15 outputs the detected power value P to the determination means 17.

The receiving unit 12 receives the bandwidth DerutaBW from the selection means 13, in the frequency band BW, radio waves wv_EX having a frequency _{f U} other frequency _{f EX} (bandwidth DerutaBW) received through the antenna 11, the received The generated radio wave wv_EX is output to the signal processing means 14.

The signal processing means 14 receives the radio waves wv_U and wv_EX from the receiving means 12, performs reception processing of the received radio waves wv_U, and generates a time response x (t) of the received signal. Further, the signal processing means 14 performs reception processing of the radio wave wv_EX, and the time response y _n (t) (= y ₁ (t), y ₂ (t), ..., Y _N (t)) of the received signal. To generate. Then, the signal processing means 14 calculates the time response x (t), y _n (t) (= y ₁ (t), y ₂ (t), ..., Y _N (t)) of the received signal. Output to 16.

The arithmetic means 16 transmits the time response x (t), y _n (t) (= y ₁ (t), y ₂ (t), ..., Y _N (t)) of the received signal from the signal processing means 14. receive.

Then, the arithmetic unit 16, the time response x of the received signal _{(t), y} n (t), are substituted into Equation (1) calculates a correlation coefficient _{r n} (step S3). In this case, calculating means _{16, y 1 (t), y} 2 (t), ···, computes the correlation coefficient _{r n} and _y N, respectively and the time response x in (t) (t). Then, the arithmetic unit 16 outputs the correlation coefficient r _n that the operation to the determination means 17.

Determination means 17 receives the power values P from the detection means 15 receives the correlation coefficient _{r n} from the arithmetic unit 16.

Then, the determination means 17 determines whether or not the power value P is equal to or less than the threshold value P_th (step S4).

When it is determined in step S3 that the power value P is equal to or less than the threshold value P_th, the determination means 17 determines that the existing system (= the wireless system of the user who has already been assigned a frequency) is not used ( Step S5).

On the other hand, in step S4, when it is determined that the power value P is not less than the threshold value P_th, determining means 17, by determining whether all of the correlation coefficients r _n is greater than the threshold r_th, having correlation It is determined whether or not there is a frequency (step S6).

In this case, the determination means 17, all correlation coefficients r _n is is greater than the threshold r_th, determines that the frequency with correlation there is less at least one threshold r_th correlation coefficient r _n, correlation It is determined that there is no frequency having.

When it is determined in step S6 that there is a frequency having a correlation, the determination means 17 determines that the received radio wave is out-of-band radiation (spurious) (step S7). Then, the series of operations proceeds to step S5.

On the other hand, when it is determined in step S6 that there is no frequency having a correlation, the determination means 17 determines that the existing system is used (step S8).

Then, after step S5 or step S8, a series of operations is completed.

In the step S6, when all correlation coefficient r _n is greater than the threshold r_th, it is described that it is determined that the frequency with correlation there, in the embodiment of the present invention is not limited thereto, the phase when a majority of the number of correlation coefficients r _n is greater than the threshold r_th, it determines that the frequency with correlation there, when a majority of the number of the correlation coefficient r _n is less than or equal to the threshold r_th, the absence frequencies having correlation You may judge.

According to the flowchart shown in FIG. 3, when it is determined that the received radio wave is out-of-band radiation (spurious), the series of operations proceeds to step S5, and it is determined that the existing system is not used ( (See steps S7 → S5), the frequency bandwidth that allows frequency sharing can be widened. That is, the frequency band of out-of-band radiation (spurious) can be used for wireless communication.

In addition, when there is out-of-band radiation (spurious), a power value P of about -85 dBm is detected. Therefore, when judging only by the power value P, when there is out-of-band radiation (spurious), the existing system can be used. It is determined that there is.

However, according to the flowchart shown in FIG. 3, when the power value P is not less than the threshold value, the frequency f time of the received signal at the _U response x (t) and the frequency f time response of the received signal at the frequency f _EX other than _U y ( Whether or not there is a correlation with t) is determined (see step S6), and when there is a correlation between the time response x (t) and the time response y (t), it is determined that there is out-of-band radiation (spurious), and the existing system It is judged that there is no use of.

Therefore, the out-of-band radiation (spurious) can be determined more accurately than the case where the determination is made only by the power value P.

[Embodiment 2]
FIG. 4 is a schematic view of the determination device according to the second embodiment. With reference to FIG. 4, the determination device 10A according to the second embodiment replaces the calculation means 16 and the determination means 17 of the determination device 10 shown in FIG. 1 with the calculation means 16A and the determination means 17A, respectively, and adds a signal generation means 18. Other than that, it is the same as that of the determination device 10.

_{The signal generating means 18 generates a signal y Primary} (t) of the primary user by a method described later, and outputs the generated _{signal y Primary} (t) to the arithmetic means 16A. The primary user is a communicator who is already authorized to use the frequency, such as radar and broadcasting.

The arithmetic means 16A receives the signal y _Primary (t) from the signal generating means 18, _{and formulates the correlation coefficient r P between the received signal y Primary} (t) and the time response x (t) of the received signal (1). Calculate by. Then, the calculation means 16A outputs the calculated correlation coefficient r _P to the determination means 17A.

The arithmetic means 16A also performs the same function as the arithmetic means 16.

The determination means 17A receives the correlation coefficient r _P from the calculation means 16A. Then, when the determination means 17A determines that the received radio wave is out-of-band radiation (spurious) by the above-mentioned method, the determination means 17A determines _{whether or not the correlation coefficient r P} is larger than the threshold value r_th. It is determined whether or not there is a correlation with the signal generation model of the next user.

Then, when the determination means 17A determines that there is a correlation with the signal generation model of the primary user, it determines that the existing system is used.

On the other hand, when the determination means 17A determines that there is no correlation with the signal generation model of the primary user, it determines that the existing system is not used.

The determination means 17A also performs the same function as the determination means 17.

A method of generating the _{signal yPrimary} (t) in the signal generating means 18 will be described.

FIG. 5 is a conceptual diagram of a bare wave. With reference to FIG. 5, the elementary waves wv_1 to wv_n (n is a positive integer) are defined by the frequency f _n , the duration T _n, and the signal strength (= power) P _n .

The elementary wave wv_1 has a frequency f ₁ , a duration | t _2- t ₁ |, and a signal strength P ₁ . Rays wv_2 the frequency _{f 2,} the duration _| having and signal strength _{P 2} | t 4 -t _3. Hereinafter, similarly, the elementary wave wv_n has a frequency f _n , a duration | t _n2- t _n1 |, and a signal strength P _n .

The start of use of the radio wave of the frequency f within the frequency bandwidth bw is defined as the generation of the elementary wave. Consider the start of radio wave use as a traffic model, and apply the Poisson process as a general model.

Then, as shown in the following equation, the frequency f _n is generated at the frequency resolution Δbw by the Poisson process.

In equation (2), m is the average wave number. Further, m / bw in the equation (2) is for normalizing the _{frequency f n to be generated. The frequency f n} in the equation (2) is a function of the frequency resolution Δbw.

_{Further, generating the frequency f n} according to the equation (2) corresponds to generating the _{frequency f n} according to the traffic model.

According to the traffic model, multiple vehicles distributed according to the Poisson process travel on the road. By applying such a traffic model, the frequency f _n is generated with the frequency resolution Δbw according to the equation (2). Therefore, if that caused the frequency f _n by applying the traffic model, the frequency f _n it will be distributed according to a Poisson process. The idea of generating a frequency f _n by applying the traffic model is novel is that the person skilled in the art did not consider in the field of wireless communications.

FIG. 6 is a conceptual diagram showing the distribution of _{frequencies f n. When the frequency f n} is generated according to the equation (2) with reference to FIG. 6, in the frequency band having the frequency bandwidth bb, there are frequencies f _{1 to} f _n having a bandwidth corresponding to the frequency resolution Δ bw.

The frequencies f _{1 to} f _n are distributed according to the Poisson process. When the bandwidth of the frequency f _n is smaller than the frequency resolution Δbw, the elementary wave _{having the frequency f n} is not generated. This is because it cannot be frequency-distinguished from an elementary wave having an adjacent frequency f _n-1.

On the other hand, when _{the bandwidth of the frequency f n} is equal to or more than the frequency resolution Δbw and smaller than 2Δbw, the elementary wave _{having the frequency f n} is generated.

As described above, the second embodiment _{is characterized in that the frequency f n} of the generated elementary wave wv_n is distributed according to the Poisson process.

The continuation model of the elementary wave is defined until the elementary wave of the frequency f _{n is generated and the transmission of the radio wave is interrupted.} Since the duration of a general call is explained by the exponential distribution, the duration of the elementary wave is defined by the exponential distribution.

That is, the duration _Tn is expressed by the following equation.

In the equation (3), Δt is the time resolution and t is the average existence time of the elementary wave. Then, in the formula (3), the duration _{T n} is a function of the time resolution Delta] t.

Since the signal strength (electric power) of the elementary wave is determined by the dynamic range of the measurement system or the positional relationship between the measurement location and the wave source, the signal strength is arbitrarily set. That is, the signal strength P _n consists of an arbitrary value between the minimum value and the maximum value.

Therefore, the signal generating means 18 generates the frequency f _n according to the Poisson process _{, determines the duration T n} according to the exponential distribution, _{and sets the signal strength P n} to an arbitrary value between the minimum value and the maximum value. The signal generating means 18, the frequency f _n, during the time that radio wave use is started until the duration time T _n has elapsed, generates an elementary waves wv_n having a signal strength P _m. The rays wv_n constitutes a signal _{y Primary} (t).

FIG. 7 is a flowchart for explaining the operation of the signal generating means 18 shown in FIG. With reference to FIG. 7, when a series of operations are started, the signal generating means 18 divides the frequency bandwidth bb by the frequency resolution Δbw to determine the average wave number m to be generated (step S11).

_{Then, the signal generating means 18 generates a frequency f n} with a frequency resolution Δbw according to the Poisson process (that is, according to the equation (2)) (step S12).

Thereafter, the signal generating means 18, according to an exponential distribution (i.e., according to equation (3)) generates a duration time _{T n} (step S13).

Subsequently, the signal generating means 18 sets the signal strength P _n to an arbitrary value between the minimum value and the maximum value (step S14).

Then, when the use of the radio wave of the _{frequency f n} is started, the signal generating means 18 generates the elementary wave wv_n having the duration T _n and the signal intensity P _{n at the frequency f n (step S15).} In this case, the signal generating means 18, when the radio wave use of frequencies _{f 1} is started, to generate rays wv_1 having a duration _{T 1} and the signal strength _{P 1} at the frequency _{f 1,} the frequency _{f 2} of the radio When the use is started, an elementary wave wv_2 having a duration T ₂ and a signal strength P _{2 is generated at the frequency f 2} , and similarly, when the use of the radio wave of the _{frequency f n is started, the frequency f At n} , a raw wave wv_n having a duration T _n and a signal strength P _{n is generated.}

Then, the signal generating means 18 determines whether or not the generated wave number is equal to the average wave number m (step S16).

When it is determined in step S16 that the number of elementary waves is not equal to the average number of elementary waves m, the series of operations shifts to step S12. After that, in step S16, steps S12 to S16 are repeatedly executed until it is determined that the number of elementary waves is equal to the average number of elementary waves m.

Then, in step S16, when it is determined that the number of elementary waves is equal to the average number of elementary waves m, a series of operations is completed.

The signal generating means 18 changes the frequency resolution Δbw and sequentially executes steps S12 to S16 each time the process shifts from step S16 to step S12.

FIG. 8 is a flowchart for explaining the operation of the determination device 10A shown in FIG. The flowchart shown in FIG. 8 is the same as the flowchart shown in FIG. 3 except that steps S21 to S23 are added to the flowchart shown in FIG.

With reference to FIG. 8, when a series of operations are started, the determination device 10A sequentially executes the above-mentioned steps S1 to S3.

Then, after step S3, the signal generating means 18 of the determination device 10A generates the elementary wave wv_n according to the flowchart shown in FIG. 6 (step S21), and outputs the generated elementary wave wv_n to the arithmetic means 16A.

Computing means 16A receives rays wv_n from the signal generating means 18 calculates a correlation coefficient _{r P} the time response x (t) of the received rays wv_n the received signal (step S22), and was the calculated The correlation coefficient r _P is output to the determination means 17A.

After that, the determination means 17A of the determination device 10A sequentially executes the above-mentioned steps S4 to S7. Then, after step S7, the determination means 17A determines whether or not there is a correlation with the signal generation model of the primary user by determining whether or not _{the correlation coefficient r P is larger than the threshold value r_th.} (Step S23).

In this case, the determination means 17A determines that there is a correlation with _{the signal generation model of the primary user when the correlation coefficient r P} is larger than the threshold value r_th, and when the correlation coefficient r _P is equal to or less than the threshold value r_th. It is determined that there is no correlation with the signal generation model of the primary user.

When it is determined in step S23 that there is no correlation with the signal generation model of the primary user, the determination means 17A determines that the existing system is not used (step S5).

On the other hand, in step S23, when it is determined that there is a correlation with the signal generation model of the primary user, the determination means 17A determines that the existing system is used (step S8).

Then, after step S5 or step S8, the series of operations ends.

According to the flowchart shown in FIG. 8, when it is determined that the received radio wave is out-of-band radiation (spurious), the existing system is further determined by determining whether or not there is a correlation with the signal generation model of the primary user. Since it is determined whether or not the existing system is used (see steps S23, S5, S8), it is possible to find a frequency that is not used by the existing system from the out-of-band radiation (spurious), and to obtain a frequency bandwidth that allows frequency sharing. Can be widened accurately.

[Embodiment 3]
FIG. 9 is a schematic view of the determination device according to the third embodiment. With reference to FIG. 9, the determination device 10B according to the third embodiment replaces the reception means 12 and the signal generation means 18 of the determination device 10A shown in FIG. 4 with the reception means 12A and the signal generation means 18A, respectively. Others are the same as the determination device 10A.

The receiving means 12A detects the received power RSSI_U when the radio wave wv_U is received, and also detects the received power RSSI_EX when the radio wave wv_EX is received. Then, the receiving means 12A outputs the detected received powers RSSI_U and RSSI_EX to the signal generating means 18A. The receiving means 12A also performs the same function as the receiving means 12.

The signal generating means 18A receives received powers RSSI_U and RSSI_EX from the receiving means 12A. Then, the signal generating means 18A compares the received power RSSI_U and RSSI_EX with the threshold value RSSI_th (for example, −95 [dBm]), sets the received power RSSI_U and RSSI_EX equal to or higher than the threshold value RSSI_th to “1”, and sets a threshold. A broadband spectrum is created by setting the received powers RSSI_U and RSSI_EX, which are smaller than the value RSSI_th, to "0".

After that, the signal generating means 18A has an actual measurement value t ₀ of the average existence time t of the elementary wave, an actual measurement value m ₀ of the average elementary wave number m, and an actual measurement value T _{n_actual of the duration of the elementary wave based on the actually measured broadband spectrum.} Is detected.

Subsequently, the signal generating means 18A obtains the average existence time t of the elementary wave by the following equation.

In equation (4), α is a correction coefficient.

Further, the signal generating means 18A obtains the average wave number m by the following equation.

In equation (5), β is a correction coefficient.

Then, the signal generating means 18A sets the correction coefficient α to the initial value α ₀ , calculates the average existence time t (= α ₀ t ₀ ) of the elementary wave, and sets the correction coefficient β to the initial value β _0. Calculate the average wave number m (= β ₀ m _0). After that, the signal generating means 18A generates the elementary wave wv_n by the same method as the signal generating means 18 using _{the average existence time t (= α 0} t ₀ ) and the average elementary wave number m (= β ₀ m _0).

When the signal generating means 18A generates the elementary wave wv_n, the signal generating means 18A detects the average elementary wave number m_cal of the generated elementary wave wv_n. The signal generating unit 18A is configured to calculates the error ΔTn between the actual measurement value _{T N_actual} in the process of generating rays wv_n equation (3) the duration _{T N_cal} of rays computed by the duration, the average number of rays The error Δm between m_cal and the measured value m _{0 of the average number of elementary waves m is calculated.}

Subsequently, the signal generating means 18A _{determines whether or not the error ΔTn is equal to} or less than the threshold value ΔT n_th and the error Δm is equal to or less than the threshold value Δm_th. The threshold value ΔT _{n_th} depends on the resolution of the measurement data and is, for example, about 0.01, and the threshold value Δm_th depends on the resolution of the measurement data and is, for example, about 0.01.

When the signal generating means 18A _{determines that at least one of the error ΔT n being equal to} or less than the threshold value ΔT n_th and the error Δm being equal to or less than the threshold value Δm_th is not satisfied, the correction coefficients α and β are set, respectively. Set to a value other than the initial values α ₀ and β _0. After that, the signal generating means 18A _{repeatedly executes the above-described operation until it is determined that the error ΔT n is equal to} or less than the threshold value ΔT n_th and the error Δm is equal to or less than the threshold value Δm_th.

Then, when the signal generating means 18A determines that the error ΔT _n is the threshold value ΔT _{n_th} or less and the error Δm is the threshold value Δm_th or less, the error ΔT _n becomes the threshold value ΔT _{n_th} or less. The correction coefficient α _{opt of is detected, and the correction coefficient β opt} when the error Δm becomes equal to or less than the threshold value Δm_th is detected.

Then, the signal generating means 18A _{substitutes the correction coefficient α opt} into the equation (4) to calculate the average existence time t (= α _opt t _{0 ) of the elementary wave, and sets the correction coefficient β opt} into the equation (5). Substitute and calculate the average wave number m (= β _oppt m ₀ ). Then, the signal generating means 18A uses the average existence time t (= α _opt t ₀ ) of the elementary wave and the average number of elementary waves m (= β _opt m ₀ ) to generate the elementary wave wv_n by the same method as the signal generating means 18. It occurs, and outputs to the computing means 16A and the generated rays wv_n as the primary user of the signal _{y primary} (t). The signal generating means 18A also performs the same function as the signal generating means 18.

FIG. 10 is a diagram showing the relationship between the actually measured received power and the frequency. In FIG. 10, the vertical axis represents the received power [dBm], and the horizontal axis represents the frequency [GHz]. Further, the curve k1 indicates the maximum power, and the curve k2 indicates the average power. Further, the threshold RSSI_th is −95 [dBm]. The relationship between the received power and the frequency shown in FIG. 10 shows the relationship between the received power and the frequency measured in the urban area of Yokohama. The measurement time is 10 minutes, and the observation band is 2.0 to 6.0 [GHz]. Further, in FIG. 10, the received power also exists in the time direction, which is the direction perpendicular to the paper surface of FIG. With reference to FIG. 10, the maximum power and the average power vary with frequency (see curves k1 and k2) and, although not shown, also with time.

FIG. 11 is a diagram showing an actual measurement example of a wideband spectrum. In FIG. 11, the vertical axis represents time [s] and the horizontal axis represents frequency [GHz]. Further, in FIG. 11, the black portion indicates a radio wave whose received power is equal to or higher than the threshold value RSSI_th, and the white portion indicates a radio wave whose received power is lower than the threshold value RSSI_th. As shown in FIG. 11, in the broadband spectrum, radio waves whose received power is equal to or higher than the threshold value RSSI_th and radio waves whose received power is smaller than the threshold value RSSI_th are distributed in the frequency direction and the time direction. You can see that.

The signal generating means 18A receives the relationship between the received power and the frequency (and time) shown in FIG. 10 from the receiving means 12A. Then, the signal generating means 18A represents a radio wave whose received power is equal to or higher than the threshold value RSSI_th by "1" based on the relationship between the received power and the frequency (and time), and the received power is higher than the threshold value RSSI_th. A wide band spectrum (see FIG. 11) is created by representing a small radio wave with “0”.

FIG. 12 is a flowchart for explaining the operation of the signal generating means 18A shown in FIG. With reference to FIG. 12, when a series of operations is started, the signal generating means 18A creates a wideband spectrum by the method described above (step S31).

Then, the signal generating means 18A detects _{the actual measurement value t 0} of the average existence time of the elementary wave, the actual measurement value m ₀ of the average elementary wave number m, and the actual measurement value _{Tn_actual of the duration of the elementary wave based on the broadband spectrum (} Step S32). After that, the signal generating means 18A sets the correction coefficients α and β to the initial values α ₀ and β ₀ , respectively (step S33).

Subsequently, the signal generating means 18A calculates the average existence time t of the _{elementary wave by t = αt 0} (α = α ₀ ), and calculates the average elementary wave number m by _{m = βm 0} (β = β _0). (Step S34). Then, the signal generating means 18A uses the average existence time t (= αt ₀ ) of the elementary waves and the average elementary wave number m (= βm ₀ ) by the same method as the signal generating means 18 (that is, the step shown in FIG. 7). Generate a raw wave wv_n (according to S12 to step S15)
Step S35).

After that, the signal generating means 18A detects the average number of elementary waves m_cal of the generated elementary waves wv_n (step S36). Then, the signal generating means 18A has an error ΔT _{n between the duration T n_cal} calculated in the process of generating the elementary wave wv_n (step S13 shown in FIG. 7) and the measured value T _{n_actual} of the duration, and the average wave number m_cal. _{The error Δm from the measured value m 0} of the average wave number is calculated (step S37).

Then, the signal generating means 18A _{determines whether or not the error ΔT n is equal to} or less than the threshold value ΔT n_th and the error Δm is equal to or less than the threshold value Δm_th (step S38). When it is determined in step S38 _{that at least one of the error ΔT n being equal to} or less than the threshold value ΔT n_th and the error Δm being equal to or less than the threshold value Δm_th is not satisfied, the signal generating means 18A determines the correction coefficient. Set α and β to values _{other than the initial values α 0} and β ₀ (step S39). After that, the series of operations returns to step S34, and steps S34 to S34 _{until it is determined in step S38 that the error ΔT n is equal to} or less than the threshold value ΔT n_th and the error Δm is equal to or less than the threshold value Δm_th. Step S39 is repeatedly executed.

Then, in step S38, when it is determined that the error ΔT _{n is equal to} or less than the threshold value ΔT n_th and the error Δm is equal to or less than the threshold value Δm_th, the signal generating means 18A determines that ΔT _n ≦ the threshold value ΔT. _{N_th,} and the correction coefficient when become Delta] m ≦ threshold Δm_th α _opt, to detect the beta _opt (step S40).

Then, the signal generating means 18A uses the average existence time t (= α _opt t ₀ ) of the elementary waves and the average number of elementary waves m (= β _opt m ₀ ) by the same method as the signal generating means 18 (that is, FIG. generating a step S12~ according to step S15) rays wv_n shown in 7 (step S41), and outputs to the operation unit 16A and the generated rays wv_n as the primary user of the signal _{y primary} (t). As a result, the operation of the signal generating means 18A is completed.

In this way, the signal generating means 18A has correction coefficients α and β so that _{the duration T n_cal} of the elementary wave wv_n approaches the actually measured value T _{n_actual} and the average elementary wave number m_cal of the elementary wave wv_n _{approaches the actually measured value m 0.} Is determined, and the elementary wave wv_n is generated based on the average existence time t and the average elementary wave number m calculated using the determined correction coefficients α and β. Therefore, it is possible to generate an elementary wave having a small error from the actually measured radio wave.

Then, generating the elementary wave wv_n according to the flowchart shown in FIG. 12 is close to the duration of the radio wave corrected so as to be close to the duration of the actually measured radio wave and the average number of elementary waves per unit time actually measured. It corresponds to generating the elementary wave wv_n by using the average number of elementary waves per unit time corrected so as to be.

The reasons why the correction coefficients α and β are required are as follows. Since the probability function (statistical value assuming the number of radio samples) is obtained from the measured data of radio waves (finite number of samples), the samples are biased. Therefore, correction coefficients α and β are required to correct this bias.

FIG. 13 is _{a diagram showing a comparison between the measured values and the calculated values of the duration T n} , the average wave number m, and the spatial density of the raw waves. In FIG. 13, the spatial density N of the elementary wave is the product of the radio wave observation time (for example, 10 minutes) and the observation bandwidth (for example, 400 MHz). More specifically, for example, the minimum unit of observation time is 1 second, the minimum unit of observation bandwidth is 1 Hz, and these are the particle sizes. In addition, the usage status of radio waves is decomposed into particles, and the usage status is set as "1" and the non-use status is set as "0". The product of the particle size of the observation time and the particle size of the observation bandwidth is set as the denominator, the total number of "1" in the radio wave usage status is set as the numerator, and the ratio is defined as the space density N.
With reference to FIG. 13, when both the correction coefficients α and β are set to “1”, _{the calculated values of the duration T n} , the average wave number m, and the spatial density N of the raw waves have an error from the measured values. large. On the other hand, when the correction coefficient α is set to “0.37” and the correction coefficient β is set to “1.37”, _{the calculated values of the duration T n} , the average wave number m, and the spatial density N of the raw waves are The error from the measured value is small.

Accordingly, the correction coefficient alpha, by correcting the average dwell time t and the average number of rays m of rays with a beta, has a duration close to the measured values T _n, the average number of rays m and rays of spatial density N We were able to demonstrate that a bare wave can be obtained.

FIG. 14 is a flowchart for explaining the operation of the determination device 10B shown in FIG. The flowchart shown in FIG. 14 is the same as the flowchart shown in FIG. 8 except that step S21 of the flowchart shown in FIG. 8 is replaced with step S21A.

With reference to FIG. 14, when a series of operations are started, the above-mentioned steps S1 to S3 are sequentially executed. Then, after step S3, the signal generating means 18A generates the elementary wave wv_n according to the flowchart shown in FIG. 12 (step S21A), and outputs the generated elementary wave wv_n to the arithmetic means 16A. After that, steps S22, S4 to S8, and S23 described above are sequentially executed, and the operation of the determination device 10B ends.

According to the flowchart shown in FIG. 14, the duration T _n close to the measured _values, it is possible to generate the elementary waves wv_n having a spatial density N of the average number of rays m and rays (see step S21A), out-of-band radiation It is possible to more accurately find frequencies that are not used by existing systems from (spurious), and to more accurately widen the frequency bandwidth that allows frequency sharing.

FIG. 15 is a schematic view of a terminal device including the determination device 10 shown in FIG. Although the antenna 11 is included in the determination device 10, it is shown outside the determination device 10 in FIG.

With reference to FIG. 15, the terminal device 100 includes a determination device 10 and a transmitter 20. The determination device 10 determines whether or not the existing system is used by the method described above, and outputs the determination result to the transmitter 20.

The transmitter 20 receives from the determination device 10 whether or not the existing system is used. Then, the transmitter 20 generates a transmission signal in a band determined that the existing system is not used, and transmits the generated transmission signal via the antenna 11.

As shown in FIG. 3, when it is determined that the radiation is out of band (spurious), it is determined that the existing system is not used (see steps S7 and S5). Therefore, the terminal device 100 has the out-of-band radiation (spurious). ) Can be used for wireless communication, and the frequency bandwidth that allows frequency sharing can be widened.

FIG. 16 is a schematic view of a terminal device including the determination device 10A shown in FIG. Although the antenna 11 is included in the determination device 10A, it is also shown outside the determination device 10A in FIG.

With reference to FIG. 16, the terminal device 100A includes a determination device 10A and a transmitter 20. The determination device 10A determines whether or not the existing system is used by the method described above, and outputs the determination result to the transmitter 20.

The transmitter 20 receives from the determination device 10A whether or not the existing system is used. Then, the transmitter 20 generates a transmission signal in a band determined that the existing system is not used, and transmits the generated transmission signal via the antenna 11.

As shown in FIG. 8, when it is determined that the radiation is out-of-band (spurious), it is determined whether or not there is a correlation with the signal generation model of the primary user, and the correlation with the signal generation model of the primary user is determined. If there is no existing system, it is determined that the existing system is not used (see "NO" and S5 in steps S7 and S23). Therefore, the terminal device 100 is used with the primary user in the frequency band of out-of-band radiation (spurious). Wireless communication can be performed using frequencies that do not correlate with each other, and the frequency bandwidth that allows frequency sharing can be accurately widened.

FIG. 17 is a schematic view of a terminal device including the determination device 10B shown in FIG. Although the antenna 11 is included in the determination device 10B, it is also shown outside the determination device 10B in FIG.

With reference to FIG. 17, the terminal device 100B includes a determination device 10B and a transmitter 20. The determination device 10B determines whether or not the existing system is used by the method described above, and outputs the determination result to the transmitter 20.

The transmitter 20 receives from the determination device 10B whether or not the existing system is used. Then, the transmitter 20 generates a transmission signal in a band determined that the existing system is not used, and transmits the generated transmission signal via the antenna 11.

Signal generating means 18A for determining apparatus 10B, the duration _{T n} close to the measured values, it is possible to generate the elementary waves wv_n having a spatial density N of the average number of rays m and rays (see step S21A), out-of-band It is possible to more accurately find frequencies that are not used by existing systems from the radiation (spurious), and to further accurately widen the frequency bandwidth that allows frequency sharing.

In the embodiment of the present invention, the operations of the determination devices 10, 10A, 10B may be executed by software.

In this case, each of the determination devices 10, 10A, and 10B includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory).

The ROM of the determination device 10 stores the program Prog_A including steps S1 to S8 of the flowchart shown in FIG.

The RAM temporarily stores the power value P, the correlation coefficient r, and the time responses x (t) and y (t).

Then, the CPU reads the program Prog_A from the ROM and executes it, and determines whether or not the existing system is used by the method described above.

Further, the ROM of the determination device 10A stores the program Prog_B including steps S11 to S16 of the flowchart shown in FIG. 7 and the program Prog_C including steps S1 to S3, S21, S22, S4 to S8, and S23 of the flowchart shown in FIG. To do.

The RAM temporarily stores the power value P, the correlation coefficient r, r _P , the time response x (t), y (t), the frequency f _n , the duration T _n, and the signal strength P _n.

Then, the CPU reads the programs Prog_B and Prog_C from the ROM and executes them, and determines whether or not the existing system is used by the method described above.

The ROM of the determination device 10B stores the program Prog_D including steps S31 to S41 of the flowchart shown in FIG. 12 and the program Prog_E including steps S1 to S3, S21A, S22, S4 to S8, and S23 of the flowchart shown in FIG. ..

The RAM has a power value P, a correlation coefficient r, r _P , a time response x (t), y (t), a frequency f _n , a duration T _n , a signal strength P _n , and actually measured values m ₀ , t ₀ , T. _{n_actual} and correction coefficients α and β are temporarily stored.

Then, the program Prog_A or the program Prog_B, Prog_C or the programs Prog_D, Prog_E may be recorded on a recording medium such as a CD or a DVD and distributed.

When the recording medium on which the program Prog_A or the program Prog_B, Prog_C or the programs Prog_D, Prog_E is recorded is attached to the personal computer, the CPU reads and executes the program Prog_A or the program Prog_B, Prog_C or the programs Prog_D, Prog_E from the recording medium, and executes the program as described above. Whether or not the existing system is used is determined by the method.

Therefore, the recording medium on which the program Prog_A or the program Prog_B, Prog_C or the programs Prog_D, Prog_E is recorded is a computer (CPU) readable recording medium.

Further, in the above, it has been described that the radio wave by the signal generation model of the primary user is generated according to the flowchart shown in FIG. 7 or FIG. 12, but in the embodiment of the present invention, the radio wave is not limited to this. The radio wave according to the signal generation model of the next user may be generated by a method other than the method shown in FIG. 7 or FIG.

Further, in the embodiment of the present invention, the signal generation model of the primary user includes a model in which the pattern of signal generation is known. A known pattern of signal generation is, for example, a weather radar. Therefore, in the embodiment of the present invention, the correlation with the known generation pattern of the signal may be calculated, and the presence or absence of use of the primary user may be determined based on the calculated correlation.

According to an embodiment of the present invention, the determination device includes a selection means for selecting a frequency, a detection means for detecting the power value of a radio wave having a frequency selected by the selection means, and a power value detected by the detection means. When is less than or equal to the threshold value, the first determination process of determining that the existing system, which is the radio system of the user who has already been assigned the frequency, is not used, and the power value detected by the detection means is larger than the threshold value. At that time, it suffices to provide a determination means for performing a second determination process for determining whether the radio wave is out-of-band radiation or the use of an existing system based on the presence or absence of a correlated frequency.

According to the configuration of such a determination device, when it is determined that the radiation is out of band, the existing system is not used, and the frequency bandwidth that can share the frequency can be widened.

Further, according to the embodiment of the present invention, the program detects the power value of the radio wave having the frequency selected in the first step by the selection means and the detection means in the first step. When the power value detected in the second step is equal to or less than the threshold value, the determination means determines that the existing system, which is the radio system of the user who has already been assigned the frequency, is not used. When the power value detected by the detection means is larger than the threshold value, it is determined whether the radio wave is out-of-band radiation or the use of the existing system based on the presence or absence of the frequency having a correlation. Any program may be used as long as it is a program for causing the computer to execute the third step of performing the second determination process.

By causing a computer to execute the program according to the embodiment of the present invention, if it is determined that the radiation is out of band, the existing system is not used, and the frequency bandwidth that can share the frequency can be widened. Because it can be done.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the description of the embodiment described above, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

The present invention applies to a determination device, a program to be executed by a computer, and a computer-readable recording medium on which the program is recorded.

10,10A, 10B determination device, 11 antenna, 12,12A receiving means, 13 selection means, 14 signal processing means, 15 detection means, 16,16A calculation means, 17,17A judgment means, 18,18A signal generation means, 20 Transmitter, 100, 100A, 100B terminal device.

Claims (17)

A selection method for selecting a frequency and
A detection means for detecting the power value of a radio wave having a frequency selected by the selection means, and a detection means.
When the power value detected by the detection means is equal to or less than the threshold value, the first determination process of determining that the existing system, which is the radio system of the user who has already been assigned a frequency, is not used, and the detection means When the detected power value is larger than the threshold value, a second determination process for determining whether the radio wave is out-of-band radiation or the use of the existing system is performed based on the presence or absence of a correlated frequency. A determination device including means. In the second determination process, the determination means determines that the radio wave is out-of-band radiation when there is a frequency having the correlation, and when there is no frequency having the correlation, the existing system is used. The determination device according to claim 1. The determination means uses the existing system when it is determined in the second determination process that the radio wave is out-of-band radiation and there is no correlation between the radio wave and the signal generation model of the primary user. The determination device according to claim 2, wherein it is determined that there is no radio wave, and when there is a correlation between the radio wave and the signal generation model of the primary user, it is determined that the existing system is used. The frequency of radio waves is generated according to the Poisson process, the duration of radio waves is generated according to the exponential distribution, and any power value selected from the range of power values defined by the minimum and maximum values of radio wave power is used as the signal strength. Further provided with a signal generating means for generating the first radio wave having the generated frequency, duration and signal strength as the radio wave of the primary user.
When there is no correlation between the first radio wave generated by the signal generating means and the second radio wave having the power value, the determination means determines that the existing system is not used, and determines that the existing system is not used. The determination device according to claim 3, wherein when there is a correlation between the radio wave and the second radio wave, it is determined that the existing system is used. The signal generating means is a radio wave duration corrected to be close to the measured radio wave duration and an average per unit time corrected to be close to the measured average wave number per unit time. The determination device according to claim 4, wherein the first radio wave is generated by using the elementary wave number. The signal generating means makes the first correction so that the first duration obtained by (the duration of the measured radio wave) × the first correction coefficient is close to the duration of the measured radio wave. While determining the coefficient, (the average number of elementary waves per unit time actually measured) × the first average number of elementary waves obtained by the second correction coefficient becomes close to the average number of elementary waves per unit time actually measured. As described above, the second correction coefficient is determined, and the determined first correction coefficient is multiplied by the duration of the actually measured radio wave to obtain the second duration and the determined second correction. The determination device according to claim 5, wherein the first radio wave is generated by using the coefficient obtained by multiplying the measured average number of elementary waves per unit time by the second average number of elementary waves. The determination means according to any one of claims 3 to 6, wherein the determination means determines whether or not there is a correlation between the radio wave and the signal generation model of the primary user by using Pearson's product moment correlation coefficient. Judgment device. The determination device according to any one of claims 2 to 7, wherein the determination means determines the presence or absence of a frequency having the correlation by using Pearson's product moment correlation coefficient. The selection means is the first step of selecting the frequency and
The second step in which the detection means detects the power value of the radio wave having the frequency selected in the first step, and
When the power value detected in the second step is equal to or less than the threshold value, the determination means determines that the existing system, which is the wireless system of the user who has already been assigned a frequency, is not used. When the power value detected by the detection means is larger than the threshold value, a second determination is made to determine whether the radio wave is out-of-band radiation or the use of the existing system based on the presence or absence of a correlated frequency. A program that causes a computer to perform a third step of processing. In the second determination process of the third step, the determination means determines that the radio wave is out-of-band radiation when there is a frequency having the correlation, and when there is no frequency having the correlation, the determination means said. The program for causing the computer according to claim 9 to execute, which determines that the existing system is used. When the determination means determines that the radio wave is out-of-band radiation in the second determination process of the third step, there is no correlation between the radio wave and the signal generation model of the primary user. , It is determined that the existing system is not used, and when there is a correlation between the radio wave and the signal generation model of the primary user, it is determined that the existing system is used. Program to let you. The signal generating means generates the frequency of the radio wave according to the Poisson process, generates the duration of the radio wave according to the exponential distribution, and any power selected from the range of the power value defined by the minimum value and the maximum value of the power of the radio wave. A fourth step of generating a value as a signal strength and generating a radio wave having the generated frequency, duration and signal strength as a radio wave of the primary user is further performed by a computer.
In the third step, the determination means means that the existing system is not used when there is no correlation between the first radio wave generated in the fourth step and the second radio wave having the power value. The program for causing the computer according to claim 11, which determines that the existing system is used when there is a correlation between the first radio wave and the second radio wave. In the fourth step, the signal generating means is corrected so that the duration of the radio wave corrected to be close to the duration of the actually measured radio wave and the average wave number per unit time actually measured are close to each other. The program for causing the computer according to claim 12, which generates the first radio wave using the average wave number per unit time. The fourth step is
The first correction so that the signal generating means makes the first duration obtained by (the duration of the measured radio wave) × the first correction coefficient close to the duration of the measured radio wave. While determining the coefficient, (the average number of elementary waves per unit time actually measured) × the first average number of elementary waves obtained by the second correction coefficient becomes close to the average number of elementary waves per unit time actually measured. As described in the first substep for determining the second correction coefficient,
The signal generating means measured the second duration obtained by multiplying the determined first correction coefficient by the measured duration of the radio wave, and the determined second correction coefficient. Executed on the computer according to claim 13, including the second substep of generating the first radio wave using the second average wave number obtained by multiplying the average wave number per unit time. Program to make you. The determination means according to claim 11 to 14, wherein in the third step, the presence or absence of correlation between the radio wave and the signal generation model of the primary user is determined by using Pearson's product moment correlation coefficient. A program for causing the computer according to any one of the items to be executed. The computer according to any one of claims 10 to 15, wherein the determination means determines in the third step whether or not there is a frequency having the correlation by using Pearson's product moment correlation coefficient. A program to execute. A computer-readable recording medium on which the program according to any one of claims 9 to 16 is recorded.

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