JP7272577B2 - Computer-readable recording medium recording a program to be executed by a management device, a computer, and the program - Google Patents

Description

The present invention relates to a management device, a program to be executed by a computer, and a computer-readable recording medium recording the program.

With the expansion of the use of unmanned aerial vehicles (UAV), the unlicensed frequency band currently in use as the frequency band used for communication by unmanned aerial vehicles (hereinafter referred to as "UAV communication") Secondary use of a certain high frequency band is under consideration (Non-Patent Document 1).

This enables high-speed, large-capacity communication such as video recording and delivery. As an example, in Japan, the use of the 5.7 GHz band currently used by radar is being considered. In that case, it is necessary to analyze the interference that UAV communication gives to the radar and use it within the range that does not adversely affect the laser.

Designing a primary user exclusion area has been proposed to address such a problem of frequency sharing (Non-Patent Document 2). This is a method of avoiding interference with the primary user by prohibiting the communication of the secondary user within the range defined by the exclusion area.

In addition, Non-Patent Document 3 divides a two-dimensional space finely into grids and distinguishes information such as the antenna gain of the primary user for each grid, thereby designing a complex-shaped exclusive area and increasing the number of secondary users. This indicates that the user can communicate.

Furthermore, Non-Patent Document 4 analyzes interference power in a three-dimensional space and proposes a method of designing an exclusion zone applicable to UAV communication.

In the analysis of interference power in Patent Document 2 to Non-Patent Document 4 described above, stochastic geometry (Non-Patent Documents 5 and 6) that handles spatial point processes is used.

JP 2018-142956 A

The Information and Communication Council, “Technical requirements for upgrading of use of radio waves for robots, etc. (in Japanese),” Mar. 2016. M. Vu, N. Devroye, and V. Tarokh, “On the primary exclusive region of cognitive networks,” IEEE Trans. Commun., vol.8, no.7, pp3380-3385, Jul. 2009. S. Yamashita, K. Yamamoto, T. Nishio, and M. Morikura, “Optimization of primary exclusive region in spatial grid-based spectrum database using stochastic geometry,” Proc. IEEE ICC2017, Paris, France, May 2017. K. Yoshikawa, S. Yamashita, K. Yamamoto, T. Nishio, and M. Morikura, “Resource allocation for 3rd drone networks sharing spectrum bands,” Proc. IEEE VTC2017-fall, Toronto, Canada, Sept. 2017. M. Haenggi, Stochastic Geometry for Wireless Networks, Cambridge Univ. Pr., Nov. 2012. H. ElSawy, E. Hossain, and M. Haenggi, “Stochastic geometry for modeling, analysis, and design of multi-tier and cognitive cellular wireless networks: A survey,” IEEE Commun. Surv. Tuts., vol. 15, no 3, pp. 996-1019, 2013. D. Schleher, “Generalized gram-charlier series with application to the sum of log-normal variates (corresp.),” IEEE Trans. Inf. Theory, vol.23, no.2, pp.275-280, May 1977. K.W. Sung, M. Tercero, and J. Zander, “Aggregate interference in secondary access with interference protection,” IEEE Commun. Lett., vol.15, no.6, pp.629-631, April 2011. M.K. Simon and M.-S. Alouini, Digital Communication over Fading Channels, John Wiley & Sons, Inc., 2004. P. Li, C. Zhang, and Y. Fang, “The capacity of wireless ad hoc networks using directional antennas,” IEEE Trans. Mobile Comput., vol.10, no.10, pp.1374-1387, Oct. 2011 . W.E. Hart, C. Laird, J.-P. Watson, and D.L. Woodruff, Pyomo Optimization Modeling in Python, vol.67, Springer Science & Business Media, 2012. A. W¨achter and L.T. Biegler, “On the implementation of an interior-point filter line-search algorithm for large-scale nonlinear programming,” Math. Program., vol.106, no.1, pp.25-27, Mar. 2006.

However, it is difficult to accurately design the exclusive area with the exclusive area design methods in Non-Patent Documents 2 to 4.

According to the embodiment of the present invention, there is provided a management device capable of accurately setting the exclusive area of the primary user.

Also, according to the embodiment of the present invention, there is provided a program for causing a computer to accurately set the exclusive area of the primary user.

Furthermore, according to the embodiment of the present invention, there is provided a computer-readable recording medium recording a program for causing a computer to accurately set the exclusive area of the primary user.

(Configuration 1)
According to this embodiment of the invention, the management device comprises computing means, determining means, and creating means.

The calculation means is distributed according to the non-uniform Poisson point process of the secondary users in each of a plurality of regions that constitute a three-dimensional region with the receiving station of the primary user as the origin where the ratio of the interfering data is a constant value. Transmission power of the transmitting station, antenna gain at the receiving station of the primary user, fading coefficient between the receiving station of the primary user and the transmitting station of the secondary user, position and origin of the transmitting station of the secondary user Using the Euclidean distance of and the propagation loss exponent, the interference power received by the primary user's receiving station from all the secondary user's transmitting stations is determined to be greater than the threshold in each of a plurality of regions. It is calculated as the probability of interference to the primary user's receiving station, which is a function of the transmission permission rate of the secondary user's transmitting station.

The determining means sets a plurality of transmission permission ratios of the secondary user's transmitting stations that minimize the number of secondary user's transmitting stations whose transmission is prohibited when the calculated interference probability is equal to or less than the target value. Determine in each of the regions.

The creating means creates an exclusion area in which only the primary user can perform wireless communication based on the transmission permission ratio of the secondary user's transmitting station in each of the determined areas.

Then, the calculation means calculates the interference power by approximating the shape of each of the plurality of regions to a three-dimensional shape having the same volume as that of each of the plurality of regions and represented by cylindrical coordinates.

(Configuration 2)
In configuration 1, the calculating means calculates the transmission power of the secondary user's transmitting station in each of a plurality of areas, the antenna gain at the primary user's receiving station, and the transmission power of the primary user's receiving station and the secondary user's Using the fading coefficient between the transmitting station, the Euclidean distance between the location of the transmitting station of the secondary user and the origin, and the propagation loss exponent, the transmitting station of the secondary user in each of the plurality of regions determines the primary usage. calculating the first interference power to be given to the receiving station of the secondary user, and using the Laplace transform of the first interference power, the nth (n is a positive integer) cumulant of the first interference power is the transmitting station of the secondary user , and based on the calculated nth-order cumulants, the interference power from all the secondary user's transmitting stations to the primary user's receiving station in a plurality of regions is the second Calculate the n-th order cumulant of the interference power, calculate the probability density function of the second interference power based on the calculated n-th order cumulant of the second interference power, and use the parameters of the calculated probability density function Calculate the interference probability.

(Composition 3)
In configuration 2, the computing means computes the n-th order cumulant of the second interference power by computing the sum of the first-order cumulant to the n-th order cumulant of the second interference power.

(Composition 4)
In any one of configuration 1 to configuration 3, the determining means multiplies the number of transmitting stations from which the secondary user transmits in each of the plurality of areas by the probability that the transmitting station of the secondary user is prohibited from transmitting. Transmission of a secondary user's transmitting station that minimizes the objective function under the constraint that the calculated interference probability is smaller than the allowable value of interference, with the result of adding the results for multiple areas as the objective function. By determining the permission ratio in each of the plurality of areas, the transmission permission ratio of the secondary user's transmitting stations that minimizes the number of secondary user's transmitting stations whose transmission is prohibited is determined.

(Composition 5)
In any one of configuration 1 to configuration 4, the secondary user transmitting stations existing in a plurality of areas, based on the transmission permission ratio, in the first frequency band shared by the primary user and the secondary user Communication is permitted, and communication of only control information in the second frequency band, which is a lower frequency band than the first frequency band, is permitted based on the transmission prohibited ratio determined from the transmission permitted ratio.

(Composition 6)
In any of Configurations 1 to 5, each of the plurality of regions has a cubic shape. The calculation means is a three-dimensional cube having the same volume as the cube and having two arc-shaped curved surfaces projecting in a direction parallel to the ground and two planes arranged in a direction perpendicular to the ground. is approximated to calculate the interference power.

(Composition 7)
Also, according to the embodiment of the present invention, the program
The calculation means is distributed according to the non-uniform Poisson point process of the secondary users in each of a plurality of regions that constitute a three-dimensional region with the receiving station of the primary user as the origin in which the ratio of the interference data is a constant value. Transmission power of the transmitting station, antenna gain at the receiving station of the primary user, fading coefficient between the receiving station of the primary user and the transmitting station of the secondary user, position and origin of the transmitting station of the secondary user Using the Euclidean distance of and the propagation loss exponent, the interference power received by the primary user's receiving station from all the secondary user's transmitting stations is determined to be greater than the threshold in each of a plurality of regions. a first step of computing as the probability of interference to the primary user's receiving station as a function of the transmission permission rate of the secondary user's transmitting station;
A determining means determines a plurality of transmission permission ratios of secondary user transmitting stations that minimize the number of secondary user transmitting stations whose transmission is prohibited while the calculated interference probability is equal to or less than a target value. a second step of determining in each of the regions;
A third step in which the creating means creates an exclusive area in which only the primary user can perform wireless communication based on the transmission permission ratio of the secondary user's transmitting station in each of the determined areas. are executed by the computer.

Then, in the first step, the calculating means approximates the shape of each of the plurality of regions to a three-dimensional shape having the same volume as that of each of the plurality of regions and is represented by cylindrical coordinates to obtain an interference power. to calculate

(Composition 8)
In configuration 7, in the first step, the computing means calculates the transmission power of the secondary user's transmitting station in each of the plurality of areas, the antenna gain at the primary user's receiving station, and the primary user's receiving station and the secondary user's transmitting station, the Euclidean distance between the location of the secondary user's transmitting station and the origin, and the propagation loss exponent, the secondary user's Calculate the first interference power that the transmitting station gives to the receiving station of the primary user, and use the Laplace transform of the first interference power to obtain the nth (n is a positive integer) cumulant of the first interference power by 2 Calculated as a function of the transmission permission rate of the next user's transmitting station, and based on the calculated n-th order cumulant, the interference from all the secondary user's transmitting stations to the primary user's receiving station in multiple regions calculating the n-th order cumulant of the second interference power which is power, calculating the probability density function of the second interference power based on the calculated n-th order cumulant of the second interference power, and calculating the calculated probability density The interference probability is calculated using the parameters of the function.

(Composition 9)
In configuration 8, in the first step, the computing means computes the n-th order cumulant of the second interference power by computing the sum from the first-order cumulant to the n-th order cumulant of the second interference power.

(Configuration 10)
In any one of configurations 7 to 9, in the second step, the determination means determines that the number of transmission stations from which the secondary users transmit in each of the plurality of areas is prohibited from transmitting from the transmission stations of the secondary users. Secondary use of minimizing the objective function under the constraint that the calculated interference probability is less than the allowable value for interference Determine the transmission permission ratio of the secondary user's transmitting station that minimizes the number of secondary user's transmitting stations whose transmission is prohibited by obtaining the transmission permission ratio of the secondary user's transmitting station in each of a plurality of areas. do.

(Composition 11)
In any one of configuration 7 to configuration 10, the transmission stations of secondary users existing in a plurality of areas operate in the first frequency band shared by the primary user and secondary users based on the transmission permission ratio. Communication is permitted, and communication of only control information in the second frequency band, which is a lower frequency band than the first frequency band, is permitted based on the transmission prohibited ratio determined from the transmission permitted ratio.

(Composition 12)
In any of configurations 7 through 11, each of the plurality of regions has a cubic shape. In the first step, the calculation means has two arc-shaped curved surfaces that have the same volume as the cube and protrude in a direction parallel to the ground, and two planes that are arranged in a direction perpendicular to the ground. Interference power is calculated by approximating the cubic shape to the dimensional shape.

(Composition 13)
Further, according to the embodiment of the present invention, the recording medium is a computer-readable recording medium recording the program according to any one of Structures 7 to 12.

The exclusive area of the primary user can be set accurately.

1 is a schematic diagram showing a communication device according to an embodiment of the invention; FIG. Fig. 2 shows an example of a system having a spatial grid according to embodiments of the invention; 2 is a configuration diagram of a management device shown in FIG. 1; FIG. 4 is a diagram showing a storage method in the storage means shown in FIG. 3; FIG. Fig. 3 is a schematic diagram of a cylindrical grid; 6 is a plan view of surfaces S3 and S4 shown in FIG. 5; FIG. 4 is a flowchart for explaining a method of creating an exclusive area PER; FIG. 8 is a flowchart for explaining detailed operations of step S1 shown in FIG. 7; FIG. FIG. 8 is a flowchart for explaining the detailed operation of step S2 shown in FIG. 7; FIG. FIG. 8 is a flowchart for explaining the detailed operation of step S3 shown in FIG. 7; FIG. 1 is a schematic diagram of a keyhole antenna; FIG. Fig. 10 shows the antenna gains in each grid and the percentage of UAVs allowed to transmit that are solutions to the optimization problem; FIG. 4 is a diagram showing the relationship between an empirical cumulative distribution function and total interference power _Iijk ; FIG. 11 shows another relationship between the empirical cumulative distribution function and the total interference power _Iijk ; FIG. 4 is a diagram showing the relationship between CCDF and total interference power I _total ; FIG. 4 is a diagram showing the relationship between the number of UAVs to be transmitted and the volume of each grid;

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

FIG. 1 is a schematic diagram showing communication equipment according to an embodiment of the present invention. Referring to FIG. 1, there are wireless communication systems WLC1 and WLC2. The wireless communication system WLC1 is a licensed wireless communication system and is called the "primary user". A wireless communication system WLC1 includes a wireless station 1 and terminals 2 and 3 . A radio station 1 is a primary user radio station, and terminals 2 and 3 are primary user terminals. Then, the radio station 1 and the terminals 2 and 3 perform radio communication with each other in the licensed frequency band.

The wireless communication system WLC2 is a wireless communication system that performs wireless communication in the frequency band of the primary user, and is called "secondary user". A wireless communication system WLC2 includes a wireless station 11 and terminals 121 to 12s (s is an integer equal to or greater than 2). A wireless station 11 is a secondary user's wireless station, and terminals 121 to 12s are secondary user's terminals. The radio station 11 and terminals 121 to 12s perform radio communication with each other in the frequency band of the primary user. Also, the radio station 11 and the terminals 121 to 12s perform radio communication of only control information in a low frequency band, which is a lower frequency band than the frequency band of the primary user. The primary user's frequency band is, for example, the 5.7 GHz band, and the low frequency band is, for example, the 169 MHz band.

Each of terminals 2 and 3 may also receive radio signals from terminals 121-12s. Each of the terminals 2 and 3 detects its own position using, for example, GPS (Global Positioning System), and transmits the detected own position to the radio station 1 .

The radio station 1 receives the positions of the terminals 2 and 3 from the terminals 2 and 3 and transmits the received positions of the terminals 2 and 3 to the radio station 11 .

A management device 10 is arranged in a radio station 11 . Management device 10 then receives the locations of terminals 2 and 3 from radio station 1 . The management device 10 also receives the positions and transmission powers of the terminals 121-12s from the terminals 121-12s.

The management device 10 uses the positions of the terminals 2 and 3, the positions of the terminals 121 to 12s, and the transmission power of the terminals 121 to 12s to establish an exclusive area in which only the primary user can perform wireless communication by a method described later. Create a PER (Primary Exclusive Region).

The terminals 121 to 12s detect their own positions using GPS, for example, and transmit the detected own positions to the management device 10. FIG. In addition, the terminals 121 to 12s detect transmission power when performing wireless communication, and transmit the detected transmission power to the management device 10. FIG.

FIG. 2 is a diagram showing an example of a system having a spatial grid according to embodiments of the invention. Referring to FIG. 2, a receiving station PR (Primary Receiver) (either terminal 2 or 3) of a primary user is set as an origin O, and space is divided into a plurality of grids GR by orthogonal coordinates (x, y, z). To divide.

Each of the plurality of grids GR has a cubic shape with a side length of l, and is divided into N _x +1, N _y +1, and N _z +1 planes in the x, y, and z directions, respectively. At this time, the volume of each grid GR is ^l3 , and each plane is x= _xi , i=0, . . . , _Nx , y= _yj , j=0, . _y , z= _zk , k=0, . . . , _Nz .

A given grid GR is represented by the following equation.

The volume of one grid GR is denoted by |V _ijk |. In the grid V _ijk , let λ _ijk be the UAV density, p _ijk be the UAV transmission power, and g _ijk be the radar (primary user) antenna gain. λ _ijk , p _ijk , and g _ijk are assumed to be constant values.

We also assume that the distribution of UAVs follows a non-uniform Poisson point process with an intensity function Λ _ijk (x,y,z) expressed by

Further, let a _ijk be the percentage of UAVs allowed to transmit in grid V _ijk . That is, the UAVs present in the grid V _ijk are permitted to communicate in the high frequency band (=frequency band shared with the primary user) only for the transmission permission ratio a _ijk , and only the ratio (1−a _ijk ) is the control information. Only low-frequency band communication is permitted (that is, high-frequency band (= frequency band shared with primary users) communication is prohibited).

A complex-shaped exclusion area is designed by determining the transmission permission ratio a _ijk for all grids V _ijk . In this case, in grid V _ijk , UAVs communicating using the high frequency band follow a non-uniform Poisson point process with intensity function a _ijk Λ _ijk (x,y,z). This point process is denoted as Φ _ijk .

It is assumed that the transmitting stations ST (Secondary Transmitters) of secondary users (one transmitting station ST consists of one of the terminals 121 to 12s) are randomly arranged in a plurality of grids V _ijk .

FIG. 3 is a configuration diagram of the management device 10 shown in FIG. Referring to FIG. 3 , management device 10 includes receiving means 101 , computing means 102 , storage means 103 , determining means 104 and creating means 105 .

The receiving means 101 receives the positions of the terminals 2 and 3 from the radio station 1 and outputs the received positions of the terminals 2 and 3 to the calculating means 102 . The receiving means 101 also receives the positions and transmission powers of the terminals 121 to 12s from the terminals 121 to 12s and outputs the received positions and transmission powers of the terminals 121 to 12s to the calculation means 102 .

The calculating means 102 receives from the receiving means 101 the positions of the terminals 2 and 3, the positions of the terminals 121 to 12s, and the transmission power of the terminals 121 to 12s.

The calculating means 102 holds in advance the volume |V _ijk | of the grid V _ijk described with reference to FIG.

The computing means 102 arranges one of the terminals 2 and 3 at the origin O of the three-dimensional space grid as the receiving station PR of the primary user.

Further, the computing means 102 computes the density λ _ijk of the transmitting stations ST of the secondary users existing in each grid V _ijk based on the positions of the terminals 121 to 12s. Then, the calculation means 102 stores the calculated density λ _ijk of the transmitting stations ST of the secondary users in the storage means 103 .

Furthermore, the calculation means 102 stores the transmission power of the terminals 121 to 12s received from the reception means 101 in the storage means 103 .

Furthermore, the calculation means 102 calculates the probability of interference with the receiving station PR of the primary user, which is a function of the transmission permission ratio _aijk of the transmitting station ST of the secondary user in each of the plurality of grids _Vijk , by a method to be described later. P(I _total >I _th ) is calculated, and the calculated interference probability P(I _total >I _th ) is output to the determining means 104 .

Storage means 103 receives the density λ _ijk of secondary user transmission stations ST and the transmission power of terminals 121 to 12s from calculation means 102, and stores the received density λ _ijk of transmission stations ST of secondary users and terminal 121 Store the transmit power for ~12s.

Further, the storage means 103 stores in advance the antenna gain _gijk . The antenna gain g _ijk is a constant that affects the directivity of the antenna of the primary user's receiving station PR and the antenna altitude of the primary user's receiving station PR or the secondary user's transmitting station ST. It is a value specific to V _ijk .

The determining means 104 receives the interference probability P(I _total >I _th ) from the computing means 102 . Then, the determining means 104 minimizes the number of transmitting stations ST of secondary users whose transmission is prohibited because the interference probability P (I _total >I _th ) is smaller than the target value β _target . is determined for each of _a plurality _{of grids V ijk .} Then, the determining means 104 outputs to the generating means 105 the transmission permission ratio a _ijk of the transmitting station ST of the secondary user in each grid V _ijk .

The creating means 105 receives from the determining means 104 the transmission permission ratio a _ijk of the transmitting station ST of the secondary user in each grid V _ijk . Then, the creating means 105 sets the grid V ijk in which the transmission permission ratio a _ijk of the secondary user's transmitting station ST is zero as an exclusion area, and sets the grid V _ijk in which the transmission permission ratio a _ijk of the secondary user's transmitting station ST is not zero. An exclusive area PER is created on the three-dimensional spatial grid using the grid V _ijk as a non-exclusive area.

FIG. 4 is a diagram showing a storage method in storage means 103 shown in FIG. Referring to FIG. 4, storage means 103 stores density λ _ijk of secondary user transmitting stations ST, position Ps of secondary user transmitting stations ST, secondary user transmission power p _ijk , antenna gain g, _ijk , radio wave loss exponent α and fading coefficient h _ijk are stored in association with each grid V _ijk .

The density λ _ijk is obtained by the computing means 102 by dividing the number of secondary user transmitting stations ST present in the grid V _ijk by the volume |V _ijk | of the grid V _ijk .

The position Ps of the secondary user's transmitting station ST is determined by the cylindrical coordinates (r, θ, z). The transmission power p _ijk is the average value of the transmission powers of the transmitting stations ST in each grid V _ijk and is a constant value.

The antenna gain g _ijk is a constant value unique to each grid V _ijk . The fading coefficient h _ijk corresponds to the position Ps of the secondary user's transmitting station ST. The radio wave loss exponent α is α>2.

A method for determining the transmission permission ratio a _ijk of the secondary user's transmitting station ST in each of a plurality of grids V _ijk will be described.

The transmitting secondary user's transmitting stations ST on grid V _ijk are distributed according to a non-uniform Poisson point process Φ _ijk with intensity function a _ijk Λ _ijk (x,y,z).

Assume that the interference to the primary user is that the total interference power I _total received from all transmitting secondary user transmitting stations ST in the primary user receiving station PR exceeds the threshold value Ith. The threshold I _th is set, for example, to a value 10 dB lower than the noise power. At this time, the interference probability to the primary user can be expressed as P(I _total >I _th ).

The total interference power I _total given to the radar (primary user) by the UAV communicating using the high frequency band is expressed by the following equation.

In equation (3), I _ijk is the total interference power from UAVs present on grid V _ijk and is given by:

In equation (4), h _x is the fading coefficient (average 1) between the UAV at coordinate s ∈ Φ _Vijk and the radar (primary user), ||d|| is coordinate d ∈ R ² is the Euclidean distance between and the origin O, and α is the propagation loss exponent (α>2).

To obtain the distribution of the total interference power I _total , the n-th order cumulant of the total interference power I _total is calculated. To do so, we first calculate the nth-order cumulant of the total interference power _Iijk .

The Laplace transform of the total interference power I _ijk can be calculated as follows using Campbell's theorem (Non-Patent Document 5).

Using Equation (5), the nth-order cumulant κ _n (I _ijk ) of the total interference power I _ijk can be expressed for n=1, 2, .

E(h ⁿ ) in Equation (6) is represented by the following equation.

Also, A _n (V) in Equation (6) is represented by the following equation.

Here, f _h (h) in Equation (7) is the probability density function of the fading coefficient h. Also, since V _ijk is a mutually independent random variable, the n-th order cumulant of the total interference power I _total is obtained as the sum of each cumulant by the following equation.

Next, equation (8) is calculated. If the grid V _ijk has a cubic shape, it is difficult to obtain the integral of A _n (V) directly, so the integral of A _n (V) is calculated based on the following approximation.

FIG. 5 is a schematic diagram of a cylindrical grid. The cubic grid V _ijk is approximated to a cylindrical grid as shown in FIG. 5 to allow integration.

Referring to FIG. 5, cylindrical grid Cy has the same volume as grid V _ijk shown in FIG. 2, and consists of a three-dimensional shape surrounded by six surfaces S1 to S6. Surface S1 is a curved surface with vertices A, B, C, and D, surface S2 is a curved surface with vertices E, F, G, and H, and surface S3 has vertices A, E, H, and D. It is flat. Further, the surface S4 is a plane having vertices B, F, G, and C, the surface S5 is a plane having vertices A, E, F, and B, and the surface S6 is a plane having vertices C, D, H, and G is a plane with

The surfaces S1 and S2 are arranged along the z-axis direction and face each other. The planes S3, S4 are arranged parallel to the xy plane and face each other. The surfaces S5 and S6 are arranged along the z-axis direction. Each of the surfaces S5 and S6 has a square shape with a side length l.

FIG. 6 is a plan view of surfaces S3 and S4 shown in FIG. Since the grid V _ijk shown in FIG. 2 has the shape of a cube, the bottom and top surfaces of the cube have a square planar shape.

On the other hand, in the case of the cylindrical grid Cy, it has an annular fan-shaped planar shape in which the length of the circular arc increases in the direction away from the origin O. FIG.

Cylindrical grid Cy satisfies the following conditions with respect to the xy plane.
(1) The intersection point connecting the midpoints of the radial direction and the circumferential direction is equal to the intersection point of the diagonal lines in the square. The coordinates are (x _io , y _jo )=((2 _i +1) l/2, (2 _j +1) l/2) in rectangular coordinates and (r _ijo , θ _ijo )=((x _io ² +y _jo ² ) ^1/2 , arctan(2 _i +1)/(2 _j +1)).
(2) The radial length is l.
(3) The central angle of the arc is l/r _ijo .

By approximating the shape of the grid V _ijk shown in FIG. 2 to the shape of the cylindrical grid Cy shown in FIGS.

Equation (10) is integrable because it includes (r ² +z ² ) ^1/2 representing the distance from the origin to each grid V _ijk in the integral. And the reason why equation (10) includes (r ² +z ² ) ^1/2 in the integral is that each grid V _ijk is represented by cylindrical coordinates (r, θ, z) as shown in FIGS. because it is represented by

Also, Equation (10) can be calculated when α>2. As a simple example, if α=3, the first and second order cumulants are given by equations (11) and (12), respectively.

b(r) in equation (11) is represented by the following equation.

Also, c(r) in Equation (12) is represented by the following equation.

As described above, the cumulant κ _n (I _total ) can be analytically determined.

The distribution of total interference power I _total is approximately calculated using cumulant matching. Cumulant matching is a technique for approximating the distribution by matching the n-th order cumulant of the desired distribution with the n-th order cumulant of a well-known distribution (Non-Patent Document 7).

In the embodiment of the present invention, as described in Non-Patent Document 8, the distribution of total interference power I _total is obtained by matching with a logarithmic normal distribution. In this case, the probability density function pdf f _Itotal of the _total interference power Itotal is expressed by the following equation.

μ ₁ in equation (15) is expressed by the following equation.

Also, σ ₁ ² in Equation (15) is represented by the following equation.

Note that the notation "κ ₁ (I _total ) ² " in equations (16) and (17) means the square of κ ₁ (I _total ).

The interference probability is defined as P(I _total >I _th ) as the probability that the total interference power I _total given to the radar (primary user) by all UAVs communicating in the high frequency band exceeds the threshold I _th . As a result, the interference probability P (I _total >I _th ) is represented by the following equation.

Q(·) in equation (18) is the Q function and is represented by the following equation.

The interference probability P (I _total >I _th ) with respect to the threshold value I _th is the same as the complementary cumulative distribution function (CCDF) of the total interference power I _total .

The threshold I _th in equation (18) is known, μ ₁ in equation (18) is represented by equation (16), σ ₁ in equation (18) is represented by equation (17), Since κ ₁ (I _total ) and κ ₂ (I _total ) in equations (16) and (17) are expressed by equations (11) and (12) respectively, the interference probability P(I _total >I _th ) is a function of the transmission grant rate a _ijk . Therefore, the interference probability P (I _total >I _th ) can be calculated by equations (11), (12), and (16) to (19).

To set the exclusion region, we formulate an optimization problem to determine the transmission-allowed fraction a _ijk in each grid V _ijk .

The objective function is the number of UAVs whose transmission is prohibited in the high frequency band, UAV _p , and is defined by the following equation.

Then, the transmission permission ratio a _ijk in each grid V _ijk is determined so as to minimize the number of UAVs UAV _p .

Also, let β _target be the allowable value of the interference probability P (I _total >I _th ), and the constraint condition is that the interference probability P (I _total >I _th ) is below the allowable value β _target .

Based on the above, the optimization problem is formulated as Equations (21) and (22).

That is, the transmission permission ratio a _ijk that satisfies the expression (21) under the constraint condition of the expression (22) is obtained for each grid V _ijk .

The computing means 102 computes the interference probability P (I _total >I _th ) by the method described above, and outputs the computed interference probability P (I _total >I _th ) to the determining means 104 .

The determining means 104 receives the interference probability P (I _total >I _th ) from the calculating means 102, and uses the equations (21) and (22) based on the received interference probability P (I _total >I _th ). Then, a transmission permission ratio a _ijk that minimizes the number of UAVs whose transmission is prohibited UAV _p is obtained for each grid V _ijk , and the obtained transmission permission ratio a _ijk (V _ijk ) (= transmission permission in each grid V _ijk ratio) to the creating means 105 .

The creating means 105 receives the transmission permission ratio a _ijk (V _ijk ) in each grid V _ijk from the determining means 104, and based on the received transmission permission ratio a _ijk (V _ijk ), in the spatial grid shown in FIG. Create an exclusive area where only the primary user can communicate. More specifically, the creating means 105 defines grids V _ijk with a transmission permission ratio a _ijk of zero as exclusive regions, and grids V _ijk with transmission permission ratios a _ijk not zero as non-exclusion regions. In the spatial grid shown in , create an exclusive area where only the primary user can communicate.

FIG. 7 is a flowchart for explaining a method of creating the exclusive area PER. Referring to FIG. 7, when the operation to create the exclusive area PER is started, the calculation means 102 calculates two grids in each of a plurality of grids forming a three-dimensional spatial grid with the receiving station of the primary user as the origin. Transmission power of the transmitting station distributed according to the non-uniform Poisson point process of the secondary user, antenna gain at the receiving station of the primary user, fading between the receiving station of the primary user and the transmitting station of the secondary user Using the coefficient, the Euclidean distance between the position of the secondary user's transmitting station and the origin, and the propagation loss exponent, the threshold that the primary user's receiving station receives from all the secondary user's transmitting stations An interference power greater than is calculated as the probability of interference to the primary user's receiving station, which is a function of the transmission permission ratio of the secondary user's transmitting station in each of the plurality of grids (step S1).

Then, computing means 102 outputs the computed interference probability to determining means 104 . The determining means 104 receives the interference probability from the computing means 102 . Then, the determining means 104 minimizes the number of secondary user transmitting stations whose calculated interference probability is smaller than the target value and whose use of the high frequency band is prohibited. A station's transmission permission percentage is determined in each of a plurality of grids (step S2).

After that, the determination means 104 outputs the transmission permission ratio determined in each grid to the creation means 105 . The creating means 105 receives the transmission permission ratio determined in each grid from the determining means 104, and based on the received transmission permission ratio, creates an exclusive area in which only the primary user can perform wireless communication ( step S3). This completes the operation of creating the exclusive area PER.

FIG. 8 is a flow chart for explaining the detailed operation of step S1 shown in FIG. Referring to FIG. 8, when the operation of creating exclusive area PER is started, computing means 102 sets i=0, j=0, and k=0 (step S11).

Then, the computing means 102 computes the Euclidean distance d between the position Ps of the secondary users existing in the grid _Vijk and the origin (step S12). More specifically, the computing means 102 reads the position Ps of the secondary user associated with the grid _Vijk (see FIG. 4) from the storage means 103, and based on the read position Ps of the secondary user, to calculate the Euclidean distance d.

After step S12, the calculation means 102 calculates the interference power _Iijk in the grid _Vijk using the transmission power _pijk in the grid Vijk, the antenna gain _gijk , the fading coefficient _hijk , the Euclidean distance d, and the propagation loss exponent _α . Calculate (step S13). More specifically, the computing means 102 reads the transmission power _{p ijk ,} the antenna gain g _ijk and the fading coefficient h _ijk (see FIG. 4) associated with the grid V ijk from the storage means 103, and the read transmission power Interference power I _ijk is calculated by substituting p _ijk , antenna gain g _ijk and fading coefficient h _ijk , Euclidean distance d and propagation loss exponent α into equation (4).

After step S13, the calculation means 102 approximates the shape of the grid V _ijk made up of cubes to the shape of a cylindrical grid, and uses the Laplace transform L _ijk of the interference power I _ijk to obtain the n-order cumulant κ _n of the interference power I _ijk (I _ijk ) is calculated (step S14). More specifically, computing means 102 computes nth-order cumulant κ _n (I _ijk ) of interference power I _ijk using equations (5) to (7) and equation (10).

Then, the calculating means 102 determines whether or not i=N _r −1 (step S15). When it is determined in step S15 that i is not i=N _r −1, the computing means 102 sets i=i+1 (step S16).

Thereafter, the series of operations proceeds to step S12, and steps S12 to S16 are repeatedly executed until it is determined that i=N _r −1 in step S15.

Then, when it is determined that i=N _r −1 in step S15, the calculating means 102 determines whether or not j=N _θ −1 (step S17).

When it is determined in step S17 that j=N _θ −1 is not obtained, the calculating means 102 sets j=j+1 (step S18).

Thereafter, the series of operations proceeds to step S12, and steps S12 to S18 are repeatedly executed until it is determined in step S17 that j=N _θ −1.

Then, when it is determined that j=N _θ −1 in step S17, the calculating means 102 determines whether or not k=N _z −1 (step S19).

When it is determined in step S19 that k=N _z −1 is not obtained, the computing means 102 sets k=k+1 (step S20). After that, the series of operations proceeds to step S12, and steps S12 to S20 are repeatedly executed until it is determined that k=N _z −1 in step S19.

Then, in step S19, when it is determined that k=N _z −1, the computing means 102 calculates all of the secondary users in the plurality of grids V _ijk based on the nth-order cumulant κ _n (I _ijk ). The nth-order cumulant κ _n (I _total ) of the total interference power I _total that is the interference power from the transmitting station to the receiving station of the primary user is analytically obtained (step S21). More specifically, computing means 102 analytically obtains the nth-order cumulant κ _n (I _total ) of the total interference power I _total using equations (10) and (11) to (14).

After that, the computing means 102 computes the probability density function of the total interference power I _total using equations (15) to (17) based on the nth-order cumulant κ _n (I _total ), and the computed probability density function Interference probability P (I _total >I _th ) is calculated using parameters μ ₁ and σ ₁ (step S22). More specifically, the interference probability P (I _total >I _th ) is calculated by substituting the parameters μ ₁ and σ ₁ into the equations (18) and (19). After step S22, the series of operations proceeds to step S2 in FIG.

FIG. 9 is a flow chart for explaining the detailed operation of step S2 shown in FIG.

Referring to FIG. 9, after step S1 shown in FIG. 7, determining means 104 determines the number of transmitting stations ST (λ _ijk |V _ijk |) from which secondary users transmit in each of a plurality of grids V _ijk . , multiplying the ratio (1-a _ijk ) of secondary user transmitting stations ST prohibited from transmitting in the high frequency band, and adding the result of multiplication for a plurality of grids V _ijk , and calculating the addition result as the objective function (step S31). More specifically, the determining means 104 computes the objective function by Equation (20).

Based on the interference probability P (I _total >I _th ) received from the computing means 102, the determining means 104 sets the constraint condition shown in Equation (22) (step S32).

After that, the determining means 104 determines the transmission permission ratio a _ijk that minimizes the objective function under the set constraint conditions (step S33). More specifically, the determining means 104 determines the transmission permission ratio a _ijk that satisfies the equation (21) under the constraint condition shown in the equation (22). This determined transmission permission ratio a _ijk is the transmission permission ratio in each grid V _ijk and consists of "0" or "1". Then, the series of operations moves to step S3 in FIG.

FIG. 10 is a flow chart for explaining the detailed operation of step S3 shown in FIG.

Referring to FIG. 10, after step S2 shown in FIG. 7, creating means 105 sets i=0, j=0 and k=0 (step S41).

Then, the creating means 105 determines whether or not the transmission permission ratio _aijk is zero (=0) (step S42).

When it is determined in step S42 that the transmission permission ratio _aijk is zero (=0), the creating means 105 sets the grid _Vijk as an exclusive area (step S43).

On the other hand, when it is determined in step S42 that the transmission permission ratio a _ijk is not zero (=0), the creating means 105 sets the grid V _ijk as a non-exclusive area (step S44).

After step S43 or step S44, the creation unit 105 determines whether i=N _r −1 (step S45). When it is determined in step S45 that i is not i=N _r −1, the creating means 105 sets i=i+1 (step S46).

After that, the series of operations proceeds to step S42, and steps S42 to S46 are repeatedly executed until it is determined that i=N _r −1 in step S45.

Then, when it is determined that i=N _r −1 in step S45, the creating means 105 determines whether or not j=N _θ −1 (step S47).

When it is determined in step S47 that j=N _θ −1 is not met, the creating means 105 sets j=j+1 (step S48).

Thereafter, the series of operations proceeds to step S42, and steps S42 to S48 are repeatedly executed until it is determined in step S47 that j=N _θ −1.

Then, when it is determined that j=N _θ −1 in step S47, the creating means 105 determines whether or not k=N _z −1 (step S49).

When it is determined in step S49 that k=N _z −1 is not obtained, the creating means 105 sets k=k+1 (step S50). After that, the series of operations proceeds to step S42, and steps S42 to S50 are repeatedly executed until it is determined that k=N _z −1 in step S49.

Then, in step S49, when it is determined that k=N _z −1, the creating means 105 creates an exclusive area of the primary user consisting of the grid V _ijk set as the exclusive area in the three-dimensional space grid ( step S51). After that, the series of operations shifts to "end" in FIG.

Thus, the management device 10 determines whether each of the plurality of grids V _ijk is an exclusive area or a non-exclusive area according to the flowchart shown in FIG. 7 (including the flowcharts shown in FIGS. 8 to 10), The exclusive area PER of the primary user, which is composed of the grids V _ijk set as the exclusive area, is created in the three-dimensional spatial grid. Therefore, the exclusive area PER of the primary user having a complicated shape can be created.

FIG. 16 of Patent Document 1 shows a three-dimensional spatial grid having a cylindrical shape, but the multiple regions that make up this three-dimensional spatial grid do not have the same volume as each other, and the volume of one region is the origin It increases with increasing distance from O in the radial direction.

As a result, the area located radially far from the origin O has a larger volume than the area located closer to the origin O, so the entire area having a larger volume is set as the exclusive area.

Therefore, in Patent Document 1, the exclusion area is set finely at a position close to the origin O, and is set coarsely at a position far from the origin O in the radial direction. Therefore, the accuracy of the exclusion area in Patent Document 1 differs depending on the distance from the origin O in the radial direction, and the accuracy of the exclusion area decreases as the distance from the origin O in the radial direction increases.

On the other hand, in the embodiment of the present invention, a plurality of grids V _ijk forming a three-dimensional spatial grid have the same volume (=l ³ ) as shown in FIG. As a result, the exclusion area can be set with a certain accuracy regardless of the distance from the origin O in both the radial direction and the height direction. If the length l of one side of one grid V _ijk is shortened, the exclusive area can be set with a certain degree of accuracy regardless of the distance from the origin O with higher accuracy.

Therefore, the exclusive area setting method according to the embodiment of the present invention is a method capable of setting the exclusive area with higher precision than the exclusive area setting method described in Patent Document 1.

The management device 10 creates the primary user's exclusive area PER by the method described above. Then, when a secondary user existing outside the created exclusive area PER of the primary user makes an inquiry as to whether or not communication is possible, the management device 10 notifies the secondary user of the fact that communication is possible. may be sent to

Numerical evaluation of the transmission permission ratio a _ijk as the optimum solution obtained under the constraint conditions will be described. In addition, the radar interference probability is evaluated by Monte Carlo simulation for the set exclusion area PER.

[Evaluation specifications]
As fading, we assume a composite fading of Nakagami m fading and lognormal shadowing (Non-Patent Document 9). At this time, E(h ⁿ ) is represented by the following equation considering E(h)=1 (Non-Patent Document 9).

(23), Γ(·) is the gamma function, m _N is the parameter of Nakagami m fading, σ _S,dB is the parameter in dB of log-normal shadowing, and ξ = 10/ln(10).

FIG. 11 is a schematic diagram of a keyhole antenna. A keyhole antenna shown in FIG. 11 (Non-Patent Document 10) is used as a radar antenna pattern.

Assuming that the mainlobe and sidelobe gains are G _m and G _S respectively, and the beam width is _θd , the antenna gain g(r, θ, φ) is expressed by the following equation.

The following relationship holds between the mainlobe gain _Gm and the sidelobe gain _Gs .

In calculating g _ijk , we use the maximum value of the antenna gain in the grid V _ijk as the worst case. That is, g _ijk is determined by the following equation.

Also, in order to pay attention to the effect of the antenna gain on the exclusion area, constant values are used for the density λ _ijk and the transmission power p _ijk .

The optimization problem (equation (21)) is implemented in Python using the modeling framework Pyomo [11] and solved using the Interior Point Optimizer (IPOPT) solver [12]. Table 1 shows the evaluation parameters.

[Exclusive area design]
FIG. 12 is a diagram showing the antenna gains in each grid and the percentage of UAVs allowed to transmit that are solutions to the optimization problem. For comparison, FIG. 12 shows antenna gains and transmission permission ratios for some heights.

Referring to FIG. 12, at low altitudes, the exclusion area is designed according to the distance to the radar (primary user), and at high altitudes, the exclusion area is designed in consideration of antenna gain.

For the approximations in the shape of the grid described above, the errors are verified by Monte Carlo simulations.

FIG. 13 is a diagram showing the relationship between the empirical cumulative distribution function and the total interference power _Iijk . In FIG. 13, the vertical axis represents the empirical cumulative distribution function, and the horizontal axis represents the total interference power _Iijk . The solid line shows the relationship between the empirical cumulative distribution function and the total interference power _Iijk when the grid has a cubic shape, and the dotted line shows the empirical cumulative distribution function and the total interference power when the grid has an approximate shape. Figure 2 shows the relationship with the power _Iijk . Note that FIG. 13 shows an empirical cumulative distribution function (ECDF) of interference power from a grid near the radar (a grid whose distance from the origin to the center of the grid is 1.56 km).

FIG. 14 is a diagram showing another relationship between the empirical cumulative distribution function and the total interference power _Iijk . In FIG. 14, the vertical axis represents the empirical cumulative distribution function, and the horizontal axis represents the total interference power _Iijk . The solid line shows the relationship between the empirical cumulative distribution function and the total interference power _Iijk when the grid has a cubic shape, and the dotted line shows the empirical cumulative distribution function and the total interference power when the grid has an approximate shape. Figure 2 shows the relationship with the power _Iijk . Note that FIG. 14 shows the empirical cumulative distribution function (ECDF) of the interference power from a grid far from the radar (a grid whose distance from the origin to the center of the grid is 2.83 km).

As shown in FIGS. 13 and 14, regardless of whether the grid is near or far from the origin, the error is small when the grid shape is a cube and when the grid shape is an approximate shape.

In the designed exclusion domain, the CCDF of the total interference power expressed by Equation (18) is evaluated by Monte Carlo simulation. FIG. 15 is a diagram showing the relationship between CCDF and total interference power I _total . In FIG. 15, the vertical axis represents CCDF, and the horizontal axis represents total interference power I _total . Also, the solid line indicates the CCDF based on the analysis formula, and the dotted line indicates the CCDF based on the simulation.

Referring to FIG. 15, it can be confirmed that the interference power is below the set threshold. In addition to the approximation in the shape of the grid, the error from the analytical formula can be attributed to the approximation error due to cumulant matching and the error due to assuming the worst case of the antenna gain.

A comparison with a cylindrical grid will be described. FIG. 16 is a diagram showing the relationship between the number of transmitting UAVs and the volume of each grid. In FIG. 16, the vertical axis represents the number of transmitted UAVs, and the horizontal axis represents the volume of each grid. In addition, the white circles show the relationship between the number of UAVs to be transmitted when the shape of the grid is cubic and the volume of each grid, and the black circles are the number of UAVs to be transmitted when the shape of the grid is cylindrical and each grid. shows the relationship with the volume of

The exclusive area PER was designed for each of the cubic grid division according to the embodiment of the present invention and the grid division based on cylindrical coordinates as shown in Patent Document 1, and the number of transmittable UAVs was compared.

As the antenna pattern, the keyhole antenna shown in FIG. 11 was used with the direction of the main lobe tilted by .pi./4 in the .theta. direction.

Referring to FIG. 16, in both cases, it was confirmed that the smaller the grid volume, that is, the larger the number of divisions, the larger the number of UAVs that can be transmitted.

It was also confirmed that the cubic grid can transmit more UAVs than the cylindrical grid in the same volume. The reason for this is considered to be the difference in the shape of the grid. In a cubic grid, the shape of the grid is the same at any coordinate, whereas in a cylindrical grid, the shape changes as the distance from the center increases. can be approximated with a shape close to the antenna pattern of Therefore, the area treated as the main lobe becomes smaller, and the exclusion area PER becomes smaller, thereby increasing the number of UAVs that can transmit.

Thus, it has been demonstrated that by using a cubic grid according to embodiments of the invention, it is possible to increase the number of UAVs that can be transmitted compared to when the grid is cylindrical in shape.

In embodiments of the present invention, the operations of management device 10 may be performed by software. In this case, the management device 10 includes a CPU (Central Processing Unit), a ROM (read only memory), and a RAM (Random Access Memory).

The ROM stores a program Prog_A consisting of the flowchart shown in FIG. 7 (including the flowcharts shown in FIGS. 8 to 10). Also _, the density λ _ijk of the secondary user transmitting stations ST shown in FIG _. and the fading coefficient h _ijk are stored in the ROM in association with the grid V _ijk .

The CPU reads the program Prog_A from the ROM, executes the read program Prog_A, and creates the exclusive area PER by the method described above.

In this case, the RAM temporarily stores intermediate calculation results in the calculation of the interference probability P (I _total >I _th ). Also, the RAM temporarily stores the determined transmission permission ratio _aijk .

Therefore, the program Prog_A is a program for causing the computer (CPU) to create the exclusive area PER.

Also, the program Prog_A may be recorded on recording media such as CDs and DVDs and distributed. In this case, the computer (CPU) reads the program Prog_A from the recording medium and executes it to create the exclusive area PER. Therefore, a CD, DVD, or the like on which the program Prog_A is recorded is a computer (CPU)-readable recording medium on which the program Prog_A is recorded.

In the above description, the management device 10 is arranged in the radio station 11, but in the embodiment of the present invention, the management device 10 is arranged in a place different from the radio station 11 without being limited to this. may also be placed separately.

Also, in the above description, the primary user is a licensed wireless communication system, but in the embodiments of the present invention, the primary user is not limited to this, and the primary user Any wireless communication system may be used as long as the ratio of data indicating the is a constant value.

Furthermore, although it has been described above that each grid V _ijk has a cubic shape, the embodiments of the present invention are not limited to this, and each grid V _ijk has two grids in the height direction of the cube. It may have a three-dimensional shape with two curved surfaces that are upwardly convex or downwardly convex, or it may have the shape of a rectangular parallelepiped, generally three-dimensionally represented by cylindrical coordinates. It may have any three-dimensional shape as long as it can approximate the shape.

According to the embodiment of the present invention, management device 10 may have the following configuration.

(Configuration 1)
The management device comprises computing means, determining means, and creating means.

The calculation means is distributed according to the non-uniform Poisson point process of the secondary users in each of a plurality of regions that constitute a three-dimensional region with the receiving station of the primary user as the origin where the ratio of the interfering data is a constant value. Transmission power of the transmitting station, antenna gain at the receiving station of the primary user, fading coefficient between the receiving station of the primary user and the transmitting station of the secondary user, position and origin of the transmitting station of the secondary user Using the Euclidean distance of and the propagation loss exponent, the interference power received by the primary user's receiving station from all the secondary user's transmitting stations is determined to be greater than the threshold in each of a plurality of regions. It is calculated as the probability of interference to the primary user's receiving station, which is a function of the transmission permission rate of the secondary user's transmitting station.

The determining means sets a plurality of transmission permission ratios of the secondary user's transmitting stations that minimize the number of secondary user's transmitting stations whose transmission is prohibited when the calculated interference probability is equal to or less than the target value. Determine in each of the regions.

The creating means creates an exclusion area in which only the primary user can perform wireless communication based on the transmission permission ratio of the secondary user's transmitting station in each of the determined areas.

Then, the calculation means calculates the interference power by approximating the shape of each of the plurality of regions to a three-dimensional shape having the same volume as that of each of the plurality of regions and represented by cylindrical coordinates.

(Configuration 2)
In configuration 1, the calculating means calculates the transmission power of the secondary user's transmitting station in each of a plurality of areas, the antenna gain at the primary user's receiving station, and the transmission power of the primary user's receiving station and the secondary user's Using the fading coefficient between the transmitting station, the Euclidean distance between the location of the transmitting station of the secondary user and the origin, and the propagation loss exponent, the transmitting station of the secondary user in each of the plurality of regions determines the primary usage. calculating the first interference power to be given to the receiving station of the secondary user, and using the Laplace transform of the first interference power, the nth (n is a positive integer) cumulant of the first interference power is the transmitting station of the secondary user , and based on the calculated nth-order cumulants, the interference power from all the secondary user's transmitting stations to the primary user's receiving station in a plurality of regions is the second Calculate the n-th order cumulant of the interference power, calculate the probability density function of the second interference power based on the calculated n-th order cumulant of the second interference power, and use the parameters of the calculated probability density function Calculate the interference probability.

(Composition 3)
In configuration 2, the computing means computes the n-th order cumulant of the second interference power by computing the sum of the first-order cumulant to the n-th order cumulant of the second interference power.

(Composition 4)
In any one of configuration 1 to configuration 3, the determining means multiplies the number of transmitting stations from which the secondary user transmits in each of the plurality of areas by the probability that the transmitting station of the secondary user is prohibited from transmitting. Transmission of a secondary user's transmitting station that minimizes the objective function under the constraint that the calculated interference probability is smaller than the allowable value of interference, with the result of adding the results for multiple areas as the objective function. By determining the permission ratio in each of the plurality of areas, the transmission permission ratio of the secondary user's transmitting stations that minimizes the number of secondary user's transmitting stations whose transmission is prohibited is determined.

(Composition 5)
In any one of configuration 1 to configuration 4, the secondary user transmitting stations existing in a plurality of areas, based on the transmission permission ratio, in the first frequency band shared by the primary user and the secondary user Communication is permitted, and communication of only control information in the second frequency band, which is a lower frequency band than the first frequency band, is permitted based on the transmission prohibited ratio determined from the transmission permitted ratio.

(Composition 6)
In any of Configurations 1 to 5, each of the plurality of regions has a cubic shape. The calculation means is a three-dimensional cube having the same volume as the cube and having two arc-shaped curved surfaces projecting in a direction parallel to the ground and two planes arranged in a direction perpendicular to the ground. is approximated to calculate the interference power.

(Composition 7)
A program that makes a computer run
The calculation means is distributed according to the non-uniform Poisson point process of the secondary users in each of a plurality of regions that constitute a three-dimensional region with the receiving station of the primary user as the origin in which the ratio of the interference data is a constant value. Transmission power of the transmitting station, antenna gain at the receiving station of the primary user, fading coefficient between the receiving station of the primary user and the transmitting station of the secondary user, position and origin of the transmitting station of the secondary user Using the Euclidean distance of and the propagation loss exponent, the interference power received by the primary user's receiving station from all the secondary user's transmitting stations is determined to be greater than the threshold in each of a plurality of regions. a first step of computing as the probability of interference to the primary user's receiving station as a function of the transmission permission rate of the secondary user's transmitting station;
A determining means determines a plurality of transmission permission ratios of secondary user transmitting stations that minimize the number of secondary user transmitting stations whose transmission is prohibited while the calculated interference probability is equal to or less than a target value. a second step of determining in each of the regions;
A third step in which the creating means creates an exclusive area in which only the primary user can perform wireless communication based on the transmission permission ratio of the secondary user's transmitting station in each of the determined areas. are executed by the computer.

Then, in the first step, the calculating means approximates the shape of each of the plurality of regions to a three-dimensional shape having the same volume as that of each of the plurality of regions and is represented by cylindrical coordinates to obtain an interference power. to calculate

(Composition 8)
In configuration 7, in the first step, the computing means calculates the transmission power of the secondary user's transmitting station in each of the plurality of areas, the antenna gain at the primary user's receiving station, and the primary user's receiving station and the secondary user's transmitting station, the Euclidean distance between the location of the secondary user's transmitting station and the origin, and the propagation loss exponent, the secondary user's Calculate the first interference power that the transmitting station gives to the receiving station of the primary user, and use the Laplace transform of the first interference power to obtain the nth (n is a positive integer) cumulant of the first interference power by 2 Calculated as a function of the transmission permission rate of the next user's transmitting station, and based on the calculated n-th order cumulant, the interference from all the secondary user's transmitting stations to the primary user's receiving station in multiple regions calculating the n-th order cumulant of the second interference power which is power, calculating the probability density function of the second interference power based on the calculated n-th order cumulant of the second interference power, and calculating the calculated probability density The interference probability is calculated using the parameters of the function.

(Composition 9)
In configuration 8, in the first step, the computing means computes the n-th order cumulant of the second interference power by computing the sum from the first-order cumulant to the n-th order cumulant of the second interference power.

(Configuration 10)
In any one of configurations 7 to 9, in the second step, the determination means determines that the number of transmission stations from which the secondary users transmit in each of the plurality of areas is prohibited from transmitting from the transmission stations of the secondary users. Secondary use of minimizing the objective function under the constraint that the calculated interference probability is less than the allowable value for interference Determine the transmission permission ratio of the secondary user's transmitting station that minimizes the number of secondary user's transmitting stations whose transmission is prohibited by obtaining the transmission permission ratio of the secondary user's transmitting station in each of a plurality of areas. do.

(Composition 11)
In any one of configuration 7 to configuration 10, the transmission stations of secondary users existing in a plurality of areas operate in the first frequency band shared by the primary user and secondary users based on the transmission permission ratio. Communication is permitted, and communication of only control information in the second frequency band, which is a lower frequency band than the first frequency band, is permitted based on the transmission prohibited ratio determined from the transmission permitted ratio.

(Composition 12)
In any of configurations 7 through 11, each of the plurality of regions has a cubic shape. In the first step, the calculation means has two arc-shaped curved surfaces that have the same volume as the cube and protrude in a direction parallel to the ground, and two planes that are arranged in a direction perpendicular to the ground. Interference power is calculated by approximating the cubic shape to the dimensional shape.

(Composition 13)
The recording medium is a computer-readable recording medium recording the program according to any one of Structures 7 to 12.

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

The present invention is applied to a management device, a program to be executed by a computer, and a computer-readable recording medium recording the program.

1, 11 radio station, 2, 3, 121 to 12s terminal, 10 management device, 101 receiving means, 102 computing means, 103 storing means, 104 determining means, 105 creating means.

Claims (13)

Transmission of transmitting stations distributed according to a non-uniform Poisson point process of secondary users in each of a plurality of regions that constitute a three-dimensional region with the origin of the receiving station of the primary user where the ratio of interference data is a constant value power, antenna gain at said primary user's receiving station, fading coefficient between said primary user's receiving station and said secondary user's transmitting station, location of said secondary user's transmitting station and said Using the Euclidean distance from the origin and the propagation loss exponent, the plurality of computing means for computing as a probability of interference to said primary user's receiving station that is a function of the percentage of said secondary user's transmitting station permitted to transmit in each region;
a transmission permission ratio of the secondary user's transmitting station that minimizes the number of the secondary user's transmitting stations whose transmission is prohibited when the calculated interference probability is equal to or less than a target value, in the plurality of regions; a determining means for determining in each of
creating means for creating an exclusion area in which only the primary user can perform wireless communication based on the transmission permission ratio of the secondary user's transmitting station in each of the determined plurality of areas; prepared,
the plurality of regions have the same volume as each other;
The arithmetic means has the same volume as the volume of each of the plurality of regions, and is three-dimensional represented by the cylindrical coordinates so that the volumes are the same even if the distance in the radial direction from the origin of the cylindrical coordinates is different. A management device that calculates the interference power by approximating the shape of each of the plurality of regions to a shape. The calculating means calculates transmission power of a transmitting station of a secondary user in each of the plurality of areas, antenna gain of a receiving station of the primary user, receiving station of the primary user and the secondary user. the transmission station of the secondary user in each of the plurality of regions using the fading coefficient between the transmitting station of Calculate a first interference power that the station gives to the receiving station of the primary user, and use the Laplace transform of the first interference power to obtain an n-order cumulant (n is a positive integer) of the first interference power is calculated as a function of the transmission permission ratio of the secondary user's transmitting station, and based on the calculated n-th order cumulant, from all the secondary user's transmitting stations in the plurality of regions to the primary user Calculate the n-th order cumulant of the second interference power, which is the interference power to the receiving station, and calculate the probability density function of the second interference power based on the calculated n-th order cumulant of the second interference power 2. The management device according to claim 1, wherein the interference probability is calculated using the parameters of the calculated probability density function. 3. The management device according to claim 2, wherein said computing means computes the n-th order cumulant of said second interference power by computing a sum of first-order cumulants to n-th order cumulants of said second interference power. The determining means multiplies the number of transmission stations transmitted by the secondary user in each of the plurality of areas by the probability that the transmission of the transmission station of the secondary user is prohibited, and multiplies the result of multiplication in the plurality of areas. Using the addition result obtained by adding the above as an objective function, and under the constraint that the calculated interference probability is smaller than the allowable value of interference, the transmission permission ratio of the secondary user's transmitting station that minimizes the objective function in each of a plurality of regions to determine a transmission permission ratio of the secondary user's transmitting stations that minimizes the number of secondary user's transmitting stations whose transmission is prohibited Item 4. The management device according to any one of items 3. the transmission stations of the secondary users existing in the plurality of areas are permitted to communicate in a first frequency band shared by the primary user and the secondary users based on the transmission permission ratio; 1 to 1, wherein communication of only control information in a second frequency band, which is a lower frequency band than the first frequency band, is permitted based on a transmission prohibition ratio determined from the transmission permission ratio. 5. The management device according to any one of 4. each of the plurality of regions has a cubic shape,
The arithmetic means has the same volume as the cube and has two arc-shaped curved surfaces protruding in a direction parallel to the ground and two flat surfaces arranged in a direction perpendicular to the ground. The management device according to any one of claims 1 to 5, wherein the interference power is calculated by approximating a cubic shape. The calculation means is distributed according to the non-uniform Poisson point process of the secondary users in each of a plurality of regions that constitute a three-dimensional region with the receiving station of the primary user as the origin in which the ratio of the interference data is a constant value. transmission power of the transmitting station, antenna gain at the receiving station of the primary user, fading coefficient between the receiving station of the primary user and the transmitting station of the secondary user, transmitting station of the secondary user Using the Euclidean distance between the position of and the origin and the propagation loss exponent, interference power greater than the threshold received by the receiving station of the primary user from all transmitting stations transmitting from the secondary user , a first step of computing as a probability of interference to said primary user's receiving station as a function of the percentage of said secondary user's transmitting station permitted to transmit in each of said plurality of regions;
A determination means determines a transmission permission ratio of the secondary user's transmitting stations that minimizes the number of secondary user's transmitting stations whose transmission is prohibited while the calculated interference probability is equal to or less than a target value. a second step of determining in each of the plurality of regions;
A creating means creates an exclusive area in which only the primary user can perform wireless communication, based on the transmission permission ratio of the transmitting station of the secondary user in each of the determined areas. causing the computer to perform the third step;
the plurality of regions have the same volume as each other;
In the first step, the calculating means has the same volume as each of the plurality of regions, and has the same volume even if the distance in the radial direction from the origin of the cylindrical coordinates is different. A program to be executed by a computer for calculating the interference power by approximating the shape of each of the plurality of regions to a three-dimensional shape represented by cylindrical coordinates. In the first step, the computing means is configured to: using the fading coefficient between the station and the secondary user's transmitting station, the Euclidean distance between the position of the secondary user's transmitting station and the origin, and the propagation loss exponent, Calculate the first interference power that the secondary user's transmitting station gives to the primary user's receiving station, and use the Laplace transform of the first interference power to n(n) of the first interference power is a positive integer) order cumulant as a function of the transmission permission rate of the secondary user's transmitting station, and based on the calculated nth order cumulant, all transmissions of the secondary user in the plurality of regions calculating the n-th order cumulant of the second interference power, which is the interference power from the station to the receiving station of the primary user, and calculating the second interference based on the calculated n-th order cumulant of the second interference power 8. The program to be executed by a computer according to claim 7, wherein the probability density function of power is calculated, and the interference probability is calculated using parameters of the calculated probability density function. 3. The calculating means, in the first step, calculates the n-th order cumulant of the second interference power by calculating the sum from the first-order cumulant to the n-th order cumulant of the second interference power. 9. A program to be executed by the computer according to 8. In the second step, the determining means multiplies the number of transmitting stations from which the secondary user transmits in each of the plurality of areas by the probability that the transmission from the transmitting station of the secondary user is prohibited. Said secondary user who uses a summation result obtained by adding multiplication results for said plurality of areas as an objective function, and minimizes said objective function under a constraint condition that said calculated interference probability is smaller than an interference allowable value. Determine the transmission permission ratio of the secondary user's transmitting station that minimizes the number of secondary user's transmitting stations whose transmission is prohibited by obtaining the transmission permission ratio of the transmitting station in each of a plurality of areas. 10. A program to be executed by the computer according to any one of claims 7 to 9. the transmission stations of the secondary users existing in the plurality of areas are permitted to communicate in a first frequency band shared by the primary user and the secondary users based on the transmission permission ratio; 7 to 8, wherein communication of only control information in a second frequency band, which is a lower frequency band than the first frequency band, is permitted based on a transmission prohibition ratio determined from the transmission permission ratio. 11. A program to be executed by the computer according to any one of 10. each of the plurality of regions has a cubic shape,
In the first step, the computing means has two arc-shaped curved surfaces having the same volume as the cube and protruding in a direction parallel to the ground, and two planes arranged in a direction perpendicular to the ground. 12. The computer program according to any one of claims 7 to 11, for calculating the interference power by approximating the shape of the cube to a three-dimensional shape having A computer-readable recording medium recording the program according to any one of claims 7 to 12.

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