JP2002300195A - Program, transmission path determination method and communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine a transmission path so as to enhance the reliability of a substitute path substituting the transmission path. SOLUTION: The program allows a computer to perform steps to acquire a configuration of the communication system. The communication system includes a receiver (2), a 1st transmitter (1-4), 1st repeaters (3-11-3-15) that transmit 1st information sent by the 1st transmitter (1-4) to the receiver (2), 2nd transmitter s (1-1-1-3) and 2nd repeaters (3-1-3-10) that transmit 2nd information sent by the 2nd transmitters (1-1-1-3) to the receiver (2). The program allows the computer to perform steps determing a 1st position of the 1st repeaters (3-11-3-15) on the basis of the 1st reliability of communication between the 1st repeaters (3-11-3-15) and the 2nd repeaters (3-1-3-10).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a program for determining a path for transmitting information from a transmitting apparatus to a receiving apparatus, and a transmission path determining method.

[0002]

2. Description of the Related Art Communication systems for transmitting information from a transmitting device to a receiving device via a relay device are widely used. In such a communication system, a transmission path for transmitting information is determined, and information is transmitted from the transmitting device to the receiving device through the determined transmission path.

As a method of determining a transmission path, there is known a method of determining a transmission path so that transmission quality is as high as possible and transmission time is shortened. Such a transmission path determination may be made based on human experience. Further, such a transmission path determination may be performed using a computer.

[0004] The transmission path thus determined includes:
Trouble may occur. For example, a relay device provided on a transmission path may fail. In addition, a problem may occur in a part of the transmission path. The trouble that has occurred interrupts the transmission path.

[0005] When a transmission path is interrupted due to a trouble, it is necessary to determine an alternative path to replace the transmission path. It is desirable that the reliability of the defined alternative route is high. Further, it is desirable that such a transmission path reconstruction be performed in a short time.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a transmission path determining method for determining a transmission path such that when a predetermined transmission path is interrupted, the reliability of an alternative path replacing the transmission path is increased. It is an object of the present invention to provide a method and a computer program for executing the method.

Another object of the present invention is to provide a transmission path determining method for determining a transmission path so that, when a predetermined transmission path is interrupted, an alternative path for replacing the transmission path can be determined in a short time. It is an object of the present invention to provide a computer program for executing a transmission path determining method.

Still another object of the present invention is to determine a transmission path so that, when a predetermined transmission path is interrupted, the reliability of an alternative path that substitutes the transmission path is increased, and the determination is made. It is an object of the present invention to provide a transmission path determining method that requires a small amount of calculation for the transmission, and a computer program for executing the transmission path determining method.

[0009]

Means for solving the problem are expressed as follows. The technical items appearing in the expression are appended with numbers, symbols, and the like in parentheses (). The numbers, symbols, and the like refer to technical matters constituting at least one of the embodiments of the present invention, particularly, technical matters expressed in the drawings corresponding to the embodiments. The reference numbers, reference symbols, and the like attached to are the same. Such reference numbers,
Reference symbols clarify the correspondence and bridging between the technical matters described in the claims and the technical matters in the embodiments. Such correspondence / bridge does not mean that the technical matters described in the claims are interpreted as being limited to the technical matters of the embodiments.

A program according to the present invention causes a computer to execute a step of acquiring a configuration of a communication system. Here, the communication system includes a receiving device (2), a first transmitting device (1-4), and the first transmitting device (1-4).
A first relay device (3-11 to 15-15) for transmitting the first information transmitted by the first device to the receiving device (2), and a second transmitting device (1-1-1).
3) and a second relay device (3--3) for transmitting the second information transmitted by the second transmitting device (1-1 to 1-3) to the receiving device (2).
1-3 to 1-10). The program further includes a first relay device (3-11 to 3-15) and a second relay device (3-11
And causing the computer to execute a step of determining a first position of each of the first relay devices (3-1-1 to 15-15) based on the first reliability of communication with the first relay device (3-1 to 3-15).

[0011] By executing the program, the first relay device (3-
The first position of 11 to 15) is determined. In the communication system, when a failure occurs in a part of a transmission path for transmitting the first information from the first transmitting device (1-4) to the receiving device (2), the second relay device (3-1 to -3) It is assumed that an alternative route is determined so as to transmit the first information via -10). The program determines the first position of the first relay device (3-11 to 15) so that the reliability of the communication of the alternative route is high. This increases the redundancy of the communication system described above.

It is preferable that the program further causes the computer to execute a step of determining a second position of the second relay device (3-1 to 3-10) based on the first reliability.

In the program, the position is represented by an evaluation function A given by the following equation: A = g ₁ (f _1,2 ), f _1,2 : the first reliability, and g ₁ : a predetermined function. It is desirable to be determined based on this.

In the program, it is preferable that the position is determined based on a second reliability of communicating the first information from the first transmitting device (1-4) to the receiving device (2).

In the program, the position is represented by the following equation: A = g ₂ (f ₁ ) + g ₃ (f _1,2 ), f _1,2 : the first reliability, f ₁ : the second reliability g ₂ , g ₃ : It is desirable to be determined based on an evaluation function A given by a predetermined function.

In the program, it is preferable that the position is determined by an annealing method using the evaluation function.

In the program, it is preferable that the position is determined by a high-dimensional algorithm using a Hamiltonian function defined based on the evaluation function.

A program according to the present invention causes a computer to execute a step of acquiring a configuration of a communication system. Here, the communication system includes a receiving device (2), first to m-th transmitting devices (1-1 to 1-4), and first to m-th transmitting devices (1-1 to 1-4), respectively. First to m-th information to be transmitted to the receiving device, respectively;
And relay devices (3-1 to 3-15). The program according to the present invention further includes a first relay device (3-11 to 3-1).
5) and the first relay device (3-11) based on the highest one of the first reliability of communication between the second to m-th relay devices (3-1 to 3-10). 3-15) causing the computer to execute the step of determining the position.

In the program, it is preferable that the position is determined based on a second reliability of communicating the first information from the first transmitting device (1-4) to the receiving device (2).

A program according to the present invention causes a computer to execute a step of acquiring a structure of a communication system. Here, the communication system includes a receiving device (2), a first (1-4) and a second transmitting device (1-1 to 1-3),
A (1, 1) -th (1, m) th relay device (3-11 to 15-15) connected in series and transmitting the first information transmitted by the first transmitting device (1-4) to the receiving device. ) And (2,1) to (2,...) Which are connected in series and transmit the second information transmitted by the second transmitting device (1-3) to the receiving device (2).
m) relay devices (3-1 to 3-10). The program further causes the computer to execute the steps of calculating the first to m-th reliability. Here, the first to m-th
The i-th reliability (i is an integer of 1 or more and m or less) of the reliability is the (1, 1) -th (1, m) -th relay device (3-1).
(1)-(i) relay device of (1-3) and (2,1)-(2, m) -th relay device (3-1-3-1).
0) is the reliability of communication with the (2, i) th relay device. The program further includes the first to m-th reliability based on the lowest one of the first to m-th reliability.
The (1, m) th relay device (3-13-13-15) and the (2,1)-(2, m) th relay device (3-1-3-1)
0) causes the computer to execute the step of determining the position.

[0021] In the program, the location may be a second reliability in communicating first information from the first transmitting device (1-4) to the receiving device (2), and the second information may be transmitted to the second transmitting device. It is desirable to be determined based on the third reliability of communication from (1-3) to the receiving device (2).

According to the transmission route determination method of the present invention, the receiving apparatus (2), the first transmitting apparatus (1-4), and the receiving apparatus (2) transmitting the first information transmitted by the first transmitting apparatus (1-4). ), The first relay device (3-11 to 3-15), the second transmitting device (1-3), and the receiving device (2) transmitting the second information transmitted by the second transmitting device (1-3). ) To the second relay device (3
-1 to 3-10). The transmission route determination method includes a first relay device (3-11 to 3-15) and a second relay device (3-1 to 3-15)
10) determining a first position of the first relay device (3-11 to 15) based on a first reliability of communication with the third relay device.

In the communication system according to the present invention, the receiving device (2), the first transmitting device (1-4), and the first information transmitted by the first transmitting device (1-4) is transmitted to the receiving device (2). A first relay device (3-1-1 to 15-15) for transmission, a second transmission device (1-1 to 1-3), and a second transmission device (1-1 to 1-1)
And (3) second relay devices (3-1 to 3-10) for transmitting the second information transmitted by (3) to the receiving device (2). The positions of the first relay devices (3-11 to 3-15) are the same as those of the first relay devices (3-11 to 3-15) and the second relay devices (3-1 to 3-15).
3-10) is determined based on the reliability of communication.

[0024]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
A transmission path determination method according to an embodiment of the present invention will be described.

First Embodiment FIG. 1 shows a communication system to which a transmission route determining method according to a first embodiment is applied.
The communication system includes first to fourth transmitting devices 1-1 to 1--1
4, the receiving device 2, and the relay devices 3-1 to 3-15. Hereinafter, the first to fourth transmission devices 1-1 to 1-4 may be collectively referred to as the transmission device 1 in some cases. Further, the relay devices 3-1 to 3-15 may be collectively referred to as the relay device 3 below.

Each of the relay devices 3 has a position Q₁~ Q_X
Located in any of the Here, X is a predetermined natural
Is a number. However, FIG.₁~ Q_XPlace of
Place Q ₁, Q₂, Q_X-1, Q_XOnly one is shown.
Position Q₁~ Q_XEach one of them
Is assigned. Position Q₁~ Q_XOut of
Position Q_iIs assigned a position number i. i is
It is an integer of 1 or more and X or less.

The transmission path network 4 is constituted by the relay device 3. And determining the transmission path network 4 is meant to determine whether each of the relay device 3 is positioned in any of the positions Q ₁ to Q _X.

The transmission path network 4 includes first to fourth transmission paths 4-
1 to 4-4. First to fourth transmission paths 4-1 to 4-4
Are configured such that five of the relay devices 3 are connected in series.

The first transmitting device 1-1 and the receiving device 2 are connected by a first transmission path 4-1. The first transmission path 4-1 includes the relay devices 3-1 and 3-2 connected in series,
3-3, 3-4, and 3-5.

The second transmitting device 1-2 and the receiving device 2 are connected by a second transmission path 4-2. The second transmission path 4-2 includes relay devices 3-6, 3-2,
3-3, 3-4, and 3-5.

The third transmitting device 1-3 and the receiving device 2 are connected by a third transmission path 4-3. The third transmission path 4-3 includes relay devices 3-7 and 3-8 connected in series,
3-9, 3-10, and 3-5.

The fourth transmission device 1-4 and the reception device 2 are connected by a fourth transmission path 4-4. The fourth transmission path 4-4 includes the relay devices 3-11 and 3-1 connected in series.
2, 3-13, 3-14, and 3-15.

The relay devices constituting the first to fourth transmission paths 4-1 to 4-4 may be shared by a plurality of the first to fourth transmission paths 4-1 to 4-4. For example, the repeaters 3-2, 3-3, and 3-4 are shared by the first transmission path 4-1 and the second transmission path 4-2.

Here, in this specification, when one of the relay devices 3 is connected to the transmitting device 1 via k-1 relay devices, the one relay device is connected to the k-th relay layer. I will state that there is. k is an integer of 1 or more and 5 or less. For example, the relay device 3 directly connected to the transmission device 1
-1, 3-6, 3-7, 3-11 are described as being in the first relay layer. Also, the relay devices 3-2, 3-8, 3-12 connected to the transmission device 1 via one relay device
Is described as being in the second relay layer. Hereinafter, third to fifth
The relay layer is defined similarly.

The position of the relay device 3 is determined by using a computer in which a program for executing the procedure of the transmission path determination method described below is installed. The computer executes the program to recognize the configuration of the communication system to be subjected to the transmission path determination method,
Further, the position of the relay device 3 is determined. Hereinafter, a process of determining the transmission path network 4 will be described.

The positions of the relay devices 3 constituting the transmission path network 4 are represented by the following equations:

(Equation 1) (1) is determined using the evaluation function A defined by:

In the equation (1), m is the number of the transmission devices 1, and in the present embodiment, m = 4. n is the number of the relay devices 3 interposed between one of the transmitting devices 1 and the receiving device 2, and in the present embodiment, n =
5.

Further, _fl is a value between two devices in a device group consisting of a transmitting device 1, a receiving device 2 connected to the k-th transmission route, and a relay device 3 constituting the k-th transmission route. Shows the reliability of communication. _fl is a positive number. f
_l indicates that the larger the value, the higher the reliability of communication between the two devices. f _l is a function that depends on the position of the two devices. That is, f _l (r,
r ') indicates the reliability of the communication between the device at position r and the device at position r'.

Α and β are predetermined constants.

The first term on the right side of the equation (1) is a term indicating the determined communication reliability of the entire transmission path network 4. The first term on the right-hand side has a larger value as the communication reliability of the determined transmission path network 4 as a whole is higher.

R _j ^k appearing in the first term on the right-hand side is a device group consisting of a transmitting device 1, a receiving device 2 connected to the k-th transmission path, and a relay device 3 constituting the k-th transmission path. Indicates the position of one. That is, r ₀ ^k is the k-th transmitting device 1
Indicates the position of -k. J that is an integer of 1 or more and n or less
For, r _j ^k, of the relay device 3, showing the position of what is in the j-th relay layer of the k transmission path. r _{n + 1} ^k is
2 shows the position of the receiving device 2.

Therefore, when j = 1, f _l (r _j ^k , r
_j-1 ^k ) indicates the communication reliability between the relay device in the first relay layer of the k-th transmission route 4-k and the k-th transmission device 1-k, and indicates the communication reliability of the k-th transmission route 4-k. It is a function of the position of the relay device in one relay layer and the position of the k-th transmitting device 1-k.

When 1 ≦ j ≦ 5, f _l (r _j ^k ,
r _j−1 ^k ) is the communication reliability between the relay device in the j−1th relay layer of the k-th transmission path 4-k and the relay device in the j-th relay layer of the k-th transmission path 4-k. And the position of the relay device in the j-1th relay layer of the k-th transmission path 4-k,
This is a function of the position of the relay device in the j-th relay layer of the transmission path 4-k.

When j = n + 1 (= 6), f
^{_{l (r j k, r j}} -1 k) denotes the communication reliability between the repeater and the receiving device 2 in the fifth relay layer of the k-th transmission path 4-k, the k-th transmission path 4 k is a function of the position of the relay device in the fifth relay layer and the position of the receiving device 2.

The first term on the right side of the equation (1) is the first to fourth transmissions.
Communication reliability r of routes 4-1 to 4-4 _r ^kAnd the constant α
Is multiplied by Communication reliability of k-th transmission path 4-k
f_r ^kIs the k-th transmission device 4-k and the k-th transmission path 4-k
The communication reliability between the relay device in the first relay layer and the k-th relay device;
2 provided on the transmission path 4-k and connected to each other
Communication reliability between the two relay devices and the fifth relay layer
Product of the communication reliability between the relay device and the receiving device 2
And

(Equation 2) ... (2) first term on the right side, the whole of the first to fourth proportional to the sum of the communication reliability _f ^r 1 _~f ^{r 4} transmission paths 4-1 to 4-4, a defined transmission path network 4 Shows the communication reliability of.

The second term on the right side is that one of the relay devices 3
This is a term indicating the reliability of an alternative path determined when a part of the first to fourth transmission paths 4-1 to 4-4 is interrupted as in the case where the function is lost.

An alternative route shall be determined as described below.

When the function of the relay device in the first relay layer of the k-th transmission path 4-k is lost, the k-th transmission device:
The first of the h-th transmission path 4-h different from the k-th transmission path 4-k
It is assumed that an alternative route is secured by being connected to the relay device in the relay layer. At this time, the h-th transmission path 4-h is selected such that the reliability of the secured alternative path is the highest.

Further, when the function of the relay device in the second to fifth relay layers is lost, the j-th transmission path 4-k
-1 It is assumed that the relay device in the relay layer is connected to the relay device in the j-th relay layer of the h-th transmission route 4-h different from the k-th transmission route 4-k, and an alternative route is secured. Where j is
It is an integer of 2 or more and 5 or less. As in the previous case, the h-th
The transmission route 4-h is selected such that the reliability of the secured alternative route is the highest.

For example, as shown in FIG.
Consider a case where the function of the relay device 3-13 in the third relay layer of the transmission path 4-4 has been lost. The second of the fourth transmission path 4-4
The relay device 3-12 in the relay layer is connected to one of the relay devices 3-3 or 3-9 to secure an alternative route. At this time, of the relay devices 3-3 or 3-9,
A device having higher communication reliability with the relay device 3-12 is selected and connected to the relay device 3-12. Relay device 3
If the communication reliability between the relay device 3-9 and the relay device 3-12 is higher than the communication reliability between the relay device 3-3 and the relay device 3-12, as shown in FIG. , Alternative route 4-
4 'is used.

The second term on the right side indicates the communication reliability of the alternative route determined in this way.

F _l (r _j−1 ^k , r appearing in the second term on the right side
_j ^h ) indicates the communication reliability between the relay device in the j-th relay layer of the k-th transmission route 4-k and the relay device in the j-th relay layer of the h-th transmission route 4-h. . Since h ≠ k,
The k-th transmission path 4-k and the h-th transmission path 4-h are different from each other.

[0053] ^{_{max (f l (r j-}} 1 k, r j h))
Is not less than 1 and not more than m (= 4), and is different from k.
F ₁ (r _j−1 ^k , r _j) calculated for
^h ) indicates the maximum value. That is, max (f
_l (r _j-1 ^k , r _j ^h )) are a plurality of alternatives that can be used when the function of the relay device in the j-th relay layer of the k-th transmission path 4-k is lost for a certain j. Of the route,
Indicates the communication reliability of the most reliable and actually used alternative route.

Min (max ( _fl ( _rj- ^1k , _rj)
^h ))) is to reduce the reliability of the least reliable alternative path when one of the relay devices constituting the k-th transmission path 4-k loses its function and the alternative path is used. Show.
That is, min (max ( _fl ( _rj- ^1k ,
r _j ^h ))) is the reliability of the alternative path when the reliability of the alternative path is the worst among the cases where one of the functions of the relay device constituting the k-th transmission path 4-k is lost. Is shown.

The second term on the right side is the first to fourth transmission paths 4-1.
Min to 4-4
^{_{(F l (r j-1}} k, r j h)) is the sum of). The second term on the right side thus determined takes a higher value as the reliability of the alternative route used when one of the intermediate devices 3 loses its function is higher.

Each position of the relay device 3 is determined so that the value of the evaluation function A becomes larger. When the positions of the relay devices 3 are determined in this manner, not only the reliability of the transmission path network 4 is high but also the reliability of the alternative path used when a part of the transmission path network 4 is interrupted. The nature becomes high. By determining each position of the relay device 3 determined using the evaluation function A, the redundancy of the transmission path network 4 is increased.

In the first embodiment, the determination of the transmission path network 4, that is, the determination of the position of each of the relay devices 3, is performed using the annealing method.

The position of the relay device 3 is determined not by the annealing method but by calculating the evaluation function A for all possible combinations of positions that the relay device 3 can take, and determining the position of the relay device 3 that maximizes the evaluation function A. Is also possible. However, such a brute force method requires a large amount of calculation. Therefore, in this embodiment, the annealing method is used to reduce the amount of calculation. In particular, when the number of transmission devices, the number of relay devices, and the number of positions that the relay devices can take are large, it is preferable to use the annealing method as in the present embodiment.

In the following description, the relay devices 3-1 to 3-3
The state where each of −15 is at a certain position will be referred to as a path state. If the position of the relay device 3-1～3-15 is determined, Sadamari is _r ^{j k} described above, therefore, the value of the evaluation function A is determined. That is, assuming that a certain path state is q, the evaluation function A is a function of q. The evaluation function A is referred to as A
(Q). q is the relay device 3-1 to 3-15
, Q = (q ₁ , q ₂ , q ₃ ,..., Q ₁₅ ).

[0060] If the position of each of the relay device 3 is determined using the annealing method, first, the path state q ⁰ is determined initially. Furthermore, the route status ^{q 0,} the relay device 3
A route state q ⁰ ′ in which a part of the positions of −1 to 3-15 is changed is determined. Further, the evaluation functions A (q ⁰ ) and A
(Q ⁰ ′) is calculated. A (q ⁰ ) and A (q ⁰ ')
, One of the route state q ⁰ and the route state q ⁰ ′ is determined to be the route state q ¹ .

Similarly, the route states q ² , q ³ ,.
q ⁱ ,... are determined. That is, for the path state q ^i-1 , the path state q ^i-1 ′ in which the position of a part of the relay devices 3-1 to 3-15 is changed is determined. Further, an evaluation function A (q ⁱ⁻¹ ) and A (q ^{i− 1} ′) are calculated. Based on A (q ^i-1 ) and A (q ^i-1 ′),
One of the route status ^{q i-1} and the path state ^{q i-1} 'is defined as the path state ^{q 1.}

Whether the path state q ⁱ becomes the path state q ^i-1 or the path state q ^i-1 ′ is determined by A (q
^i-1 ) and A (qi ^-1 ') are represented by the following formula:

(Equation 3) .. (3) is determined based on whether or not the following condition is satisfied. Where ra
ndom [0, 1] is a random number from 0 to 1. T
(I) is the temperature determined by the annealing method. Temperature T
(I) monotonically decreases as i increases.

A (q^i-1) And A (q^i-1’) Is an expression
When (3) is satisfied, the route state q _iIs qⁱ= Q^i-1’.

A (q ^i-1 ) and A (q ^i-1 ′) are
If the equation (3) is not satisfied, the path state q _i is represented by q ⁱ = q ⁱ⁻¹ .

When A (q ⁱ⁻¹ ) <A (q ⁱ⁻¹ ′), the right side of equation (3) becomes larger than 1 and equation (3)
Holds. ^{A (q i-1) <} A (q i-1 ') and when it is, rather than route status ^{q i-1,} the path state ^{q i-1'} towards to increase the value of more evaluation function A It is time. In such a case, the route state q ⁱ is always
Position of the relay device 3 from the path state q ^i-1 is determined to be changed path state q ^{i-1 '.}

On the other hand, A (q ⁱ⁻¹ ) ≧ A (q ⁱ⁻¹ ′)
, Equation (3) may or may not be established stochastically. That is, the path state q ⁱ is
Either ^i-1 or the route state q ^i-1 ′ is determined stochastically. A (q ^i-1 ) ≧
Even in the case of A (q ⁱ⁻¹ ′), the path state q ⁱ
Is determined to be the path state q ^i-1 ′ in order to make it difficult for the optimum path state, which is the purpose of the calculation, to be caught by a local stable solution.

[0067] 'even if the path state ^{q i} is the path state ^{q i -1 A (q i-} 1) ≧ A (q i-1)' probability defined to be the basis of the temperature T (i) Is determined. Temperature T
Since (i) monotonically decreases with respect to i, A (q
^i-1) probabilities is defined as a 'route status ^{q i} is the path state ^{q i-1} in the case ^{of)' ≧ A (q i-} 1 decreases as i increases.

When the path state q ⁱ is sequentially determined in this manner, the path state q ⁱ generally approaches the path state that maximizes the evaluation function A as the subscript i increases. Until a predetermined condition is satisfied, is determined sequentially route state q ^i, finally, the optimal route condition is calculated is the object of calculation.

The process of executing the above-described annealing method will be described step by step.

Step S0: The structure of the communication system which is the object of the transmission path determination method is recognized. Further, the positions of the relay devices 3-1 to 3-15 are initially determined. The path state determined by the position of the initially defined relay device 3-1～3-15, the path state ^{q 0.}

[0071] Step S1: p pieces of the path state ^{q 0} in which the relay apparatus defined in 3-1～3-15 is changed, the path state ^{q 0} to be compared with the path state ^{q 0} '
Is determined. The path state q ⁰ ′ is determined by executing steps S2 to S5 described below.

Step S2: The number M of relay devices whose positions are to be changed is determined. The number M of relay devices that change the position is
It is determined to be one integer selected with equal probability from an integer of 1 or more and m × n or less. Here, m is the number of transmitting devices 1 and n is the number of relay layers.

Step S3: first to fourth transmission paths 4-1
One of the transmission paths is selected with equal probability from ４−4-4.

Step S4: One of the first to fifth relay layers is selected with equal probability. One relay device on the relay layer selected in step S2 on the transmission path selected in step S2 is determined. After that, the relay device
It is described as a selective relay device.

Step S5: N positions near the position where the selected repeater determined in step S3 is located are selected. N is a predetermined natural number. One position is further selected from the selected N positions. The position of the selected relay device is changed to the one selected position.

Steps S2 to S5 described later are repeated M times.
returned. Thereby, the route state q ⁰To relay device 3-
Route state q in which M of 1-3-15 have been changed⁰’
Is determined. Subsequently, step S6 is performed.

Step S6: A (q ⁰ ) and A (q ⁰ ′)
Compared bets is determined the path state q ^1. Path status q
¹ is determined to be ^one of the path state q ⁰ and the path state q ⁰ ′. Route status ^{q 1} is, either has any route state ^{q 0} and the path state ^{q 0} ', A and ^{(q 0)} A
(Q ⁰ ′) and the following equation:

(Equation 4)(3) 'is determined based on whether or not the following condition is satisfied. A (q⁰)When
A (q⁰) Satisfies Equation (3) ', the path state
q¹Is q¹= Q⁰’. Also, A (q⁰) And A (q⁰) Satisfies Equation (3) '
When not, the route state q ¹Is q¹= Q⁰.

Hereinafter, route states q ² , q ³ ,... Are sequentially determined by the same process as steps S ² to S 6.
Until a predetermined condition is satisfied, is determined sequentially route state q ^i, finally, the optimal route condition is calculated is the object of calculation.

The determination of the position of the relay device 3 by the above-described annealing method is performed using a computer in which a program for repeatedly executing steps S2 to S6 is installed. The computer determines the position of the relay device 3 by executing the program.

In the transmission route determination method according to the present embodiment, the position of the relay device 3 is determined using the evaluation function A in consideration of the reliability of the alternative route when the transmission route is interrupted. As a result, not only is the reliability of the transmission path network 4 high, but also
The reliability of the alternative path used when a part of the transmission path network 4 is interrupted increases. Furthermore, the amount of calculation when determining the position of the relay device 3 is reduced, and the time for determining the transmission path network 4 is reduced.

It is obvious that the transmission route determining method of the present embodiment can be applied to the transmission route network 4 having another configuration. Number of transmitting devices 1, relay devices 3
The transmission path determination method of the present embodiment is applied to transmission path networks in which the number of
Naturally, the position of each relay device 3 can be determined.

Second Embodiment: The transmission route determination method according to the second embodiment determines the position of the relay device of the transmission system shown in FIG. 1 similarly to the transmission route determination method according to the first embodiment. Target. Also, in the second embodiment, similarly to the first embodiment, the evaluation function A shown in Expression (1) is used for determining the position of the relay device 3.

However, in the second embodiment, a high-dimensional algorithm is used to determine the position of the relay device 3. In this respect, the second embodiment differs from the first embodiment in which the annealing method is used. Hereinafter, a second embodiment will be described.

The high-dimensional algorithm is an algorithm that solves an optimization problem by utilizing autonomous motion of a dynamic system in a high-dimensional space. In the present embodiment, the particle position q in the high-dimensional space is associated with the position of the relay device 3. The particle position q is q = (q ₁ , q ₂ ,..., Q ₁₅ ) with the positions of the relay devices 3-1 to 3-15 as q _{1 to} q ₁₅ respectively. q is a position in the 15-dimensional space determined corresponding to the position of the relay devices 3-1 to 3-15. q ₁ , q ₂ , ...,
q ₁₅ takes one of the values of the defined position number corresponding to the position Q ₁ to Q _X. That is, q ₁ , q ₂ ,
..., q ₁₅ is any of the following integer 1 or X.

Further, a momentum p is introduced to optimize the positions of the relay devices 3-1 to 3-15. The momentum p is
A 15-dimensional vector, p = (p ₁ , p ₂ ,..., P ₁₅ ).

The Hamiltonian function H (p, q) is defined as H (p, q) = A (q) + g (p, q).

A (q) is the evaluation function A shown in the above equation (1). _R ^j k, _r included in the evaluation function A
_j−1 ^k and r _j ^h are uniquely determined when the particle position q is determined. That is, the evaluation function A is a function of the particle position q. Therefore, the evaluation function A is described as A (q), and is clearly a function of the particle position q.

G (p, q) is a mixed term. Mixed term g
(P, q) is defined as a certain function that is a function of the particle position q and the momentum p under the condition that the mixing property is ensured.

Using the Hamiltonian function H (p, q) thus determined, the position of the relay device 3 is determined. Hereinafter, the process will be described.

Step S10: First, initial values of the particle position q and the momentum p are set. Relay devices 3-1 to 3-15
Is initially determined, and the particle position q is determined.
The initial value of the particle position q are described as q ^{0. _{q 0 = (q 1 0,}} q 2 0, ..., q 15 0). q ₁ ⁰ to q ₁₅ ⁰ is an integer 1 or more X.

[0091] Step S11: a part of the fifteen components of the particle position ^{q 0} is changed is determined particle positions ^{q 0} '. A part of the fifteen components of the particle position q ⁰ is changed, the relay apparatus in the initial state 3-1～3-
15 means that a part of the position is changed.

Step S12: The differential ΔA ⁰ / Δq _i ⁰ of the evaluation function A (p, q) is calculated by the following equation:

(Equation 5) Required by

[0093] step S13 momentum ^{p 1} is the following formula:

(Equation 6) (4) Here, ΔH ⁰ / Δq _i is:

(Equation 7) … (5) However,

(Equation 8) ... (6). By transforming equation (4),

(Equation 9) .. (4) ′ where p _i ⁰ and p _i ¹ are the momentums p ⁰ and p ¹ , respectively.
¹ is each component. Δt is a predetermined constant. Momentum ^{p 1} determined by the equation (4) '.

Step S14: The particle position q ⁰ ″ is calculated by the following equation:

(Equation 10) … (7) That is,

[Equation 11] ... (7) '. here,

(Equation 12)It is. Particle position q⁰Hamiltoni appears in the formula for calculating
Anh's derivative ΔH⁰’/ Δp_i ⁰Is calculated in step S
Momentum p calculated in 13¹Is used. Differentiation Δ
H⁰’/ Δp_i ⁰Is dashed (prime)
Therefore, the momentum p ⁰ΔH calculated using⁰
/ Δp_i ⁰Are distinguished from Derivative Δ of mixing term g
g⁰’/ Δp_i ⁰The same is true for

The above equations (7) and (4) are the equations of motion of a general Hamiltonian dynamical system:

(Equation 13) It corresponds to. That is, the particle position q ⁰ ″ is determined according to the equation of motion of the dynamical system in the virtual space that is virtually determined.

[0096] Step S15: particle position ^{q 1} is determined. When the particle position q ⁰ ″ coincides with the particle position q ⁰ ′, the particle position q ¹ is defined as q ¹ = q ⁰ ′. On the other hand, the particle position q ⁰ ″ and the particle position q ⁰ ′.
If bets do not match, the particle position ^{q 1} is, ^q 1 ^{= q} 0, is defined as.

Step S16: Steps S11 to S15
, The particle positions q ² , q ³ ,... Are sequentially determined.

At this time, the momentum p¹And particle position q¹And to
Based on the momentum p²And particle position q ²Is required.
Similarly, the momentum p^j-1And particle position q^j-1Based on
And the momentum p^jAnd particle position q^jIs required. here
And j is a natural number.

[0099] Momentum ^{p j-1} and particle position ^{q j-1} and the process of the momentum ^{p j} and the particle position ^{q j} is obtained based on is the same as step S11 to S16.

[0100] That is, first, changed some of the fifteen components of the particle position ^{q j-1,} is defined particle position ^{q j-1} '.

Further, the momentum p ^j is given by the following equation.

[Equation 14] Required by here,

(Equation 15)

Further, the particle position q ^j-1 ″ is expressed by the following equation:

(Equation 16) Defined by here,

[Equation 17]

Further, the particle position q ^j-1 ″ and the particle position q
^{When j-1} ′ matches, the particle position q ^j is defined as q ^j = q ^j−1 ′. On the other hand, the particle position q ^j−1 ″ and the particle position q
^{If j-1} 'does not coincide, the particle position ^{q j is, q j = q j-1} , it is defined as.

Step S17: Steps S11 to S16
For each of the particle positions q ¹ , q ² , q ^3, ... Determined by the evaluation function A (q ¹ ), A (q ² ),
² ),... Are calculated. Particle position ^{q 1, q 2, q 3} ... of the particles position to maximize the evaluation function A ^{q ma x} is determined.

The determination of the position of the relay device 3 by the above-described high-dimensional algorithm is performed using a computer in which a program for executing steps S11 to S17 is installed. The computer determines the position of the relay device 3 by executing the program.

In the transmission route determination method according to the present embodiment, the position of the relay device 3 is determined by using the evaluation function A in consideration of the reliability of the alternative route when the transmission route is interrupted. As a result, not only is the reliability of the transmission path network 4 high, but also
The reliability of the alternative path used when a part of the transmission path network 4 is interrupted increases. Furthermore, the amount of calculation when determining the position of the relay device 3 is reduced, and the time for determining the transmission path network 4 is reduced.

It is obvious that the transmission route determination method of the present embodiment can be applied to the transmission route network 4 having another configuration. Number of transmitting devices 1, relay devices 3
The transmission path determination method of the present embodiment is applied to transmission path networks in which the number of
Naturally, the position of each relay device 3 can be determined.

[0108]

According to the present invention, when a predetermined transmission path is interrupted, a transmission path determination method and a transmission path determination method for determining a transmission path so as to increase the reliability of an alternative path that substitutes the transmission path. A computer program for performing the determining method is provided.

Further, according to the present invention, when a predetermined transmission path is interrupted, a transmission path determination method and a transmission path determination method for determining a transmission path so that an alternative path to substitute the transmission path can be determined in a short time. A computer program for performing the method is provided.

Further, according to the present invention, when a predetermined transmission path is interrupted, the transmission path is determined so that the reliability of an alternative path which substitutes the transmission path is increased, and
A transmission path determination method requiring a small amount of calculation for the determination and a computer program for executing the transmission path determination method are provided.

[Brief description of the drawings]

FIG. 1 shows a communication system in which a transmission path is determined by a transmission path determination method according to an embodiment of the present invention.

FIG. 2 shows an alternative route.

[Explanation of symbols]

 1-1: First transmitting device 1-2: Second transmitting device 1-3: Third transmitting device 1-4: Fourth transmitting device 2: Receiving device 3-1 to 3-15: Relay device

 ──────────────────────────────────────────────────続 き The continuation of the front page F term (reference) 5K030 GA12 HD03 JA11 LB08

Claims (13)

[Claims] 1. A step of acquiring a configuration of a communication system, wherein the communication system transmits a receiving device, a first transmitting device, and first information transmitted by the first transmitting device to the receiving device. A first relay device, a second transmission device, and a second relay device that transmits second information transmitted by the second transmission device to the reception device, wherein the first relay device, the second relay device, Determining the first position of the first relay device based on the first reliability of communication between the first and second relay devices. 2. The program according to claim 1, further comprising a step of determining a second position of the second relay device based on the first reliability. 3. The program according to claim 1, wherein the position is given by the following equation: A = g ₁ (f _1,2 ), f _1,2 : the first reliability, and g ₁ : a predetermined function. A program determined based on the evaluation function A to be obtained. 4. The program according to claim 1, wherein the position is determined based on a second reliability of communicating the first information from the first transmitting device to the receiving device. 5. The program according to claim 1, wherein the position is represented by the following equation: A = g ₂ (f ₁ ) + g ₃ (f _1,2 ), f _1,2 : the first reliability, f ₁ : The second reliability g ₂ , g ₃ : a program determined based on an evaluation function A given by a predetermined function. 6. The program according to claim 3, wherein the position is determined by an annealing method using the evaluation function. 7. The program according to claim 3, wherein the position is determined by a high-dimensional algorithm using a Hamiltonian function determined based on the evaluation function. 8. A step of acquiring a configuration of a communication system, wherein the communication system comprises: a receiving device; first to m-th transmitting devices; M-th
First to m-th relay devices each transmitting information to the receiving device, wherein the first reliability of communication between the first relay device and each of the second to m-th relay devices Determining the position of the first relay device based on the highest one. 9. The program according to claim 8, wherein the position is determined based on a second reliability of communicating the first information from the first transmitting device to the receiving device. 10. A step of acquiring a structure of a communication system, wherein the communication system is connected in series with a receiving device, a first and a second transmitting device, and the first transmitting device transmits the first transmitting device. (1, 1) to (1, m) transmitting information to the receiving device
And (2, 1) to (2, m) connected in series with the relay device and transmitting the second information transmitted by the second transmission device to the reception device.
Calculating a first to m-th reliability; and wherein the i-th reliability (i is 1 to m) of the first to m-th reliability is included.
(The following integer) is the (1, i) th relay device among the (1, 1) to (1, m) th relay devices, and the (2,
The reliability of communication with the (2, i) th relay device among the (1) to (2, m) th relay devices, based on the lowest one of the first to mth reliability devices. And a step of determining the positions of the (1,1) -th (1, m) th relay device and the (2,1)-(2, m) th relay device. 11. The program according to claim 10, wherein the location is a second reliability of communicating the first information from the first transmitting device to the receiving device, and transmitting the second information from the second transmitting device. A program defined based on third reliability for communicating with the receiving device. 12. A receiving device, a first transmitting device, a first relay device for transmitting first information transmitted by the first transmitting device to the receiving device, a second transmitting device, and the second transmitting device. A transmission route determination method for a communication system including a second relay device that transmits second information transmitted by the first relay device to the receiving device, wherein a first relay device communicates between the first relay device and the second relay device. A transmission path determination method, comprising: determining a first position of the first relay device based on reliability. 13. A receiving device, a first transmitting device, a first relay device transmitting first information transmitted by the first transmitting device to the receiving device, a second transmitting device, and the second transmitting device. And a second relay device for transmitting the second information transmitted by the first relay device to the receiving device. A communication system defined based on this.