JP5483472B2 - Line assignment apparatus and line assignment method - Google Patents

Description

  The present invention relates to a wireless communication system in which a terminal station communicates via a communication satellite or a mobile communication cellular base station (hereinafter referred to as a “node station”) for transmitting a communication line divided into a plurality of bandwidths. The present invention relates to a line assignment apparatus and a line assignment method.

  In a wireless communication system in which a terminal station communicates via a node station, the total bandwidth of a line allocated to each terminal station is limited to a bandwidth (system bandwidth) that can be used by the node station. In order to effectively use the system band, a demand assignment method (Non-patent Document 1) is used in which a line is dynamically allocated to a terminal station that starts communication and the line is released when communication ends.

  In the demand assignment method, each terminal station asynchronously repeats line assignment and line release, and the free band is distributed over the system band. Therefore, band dispersion transmission (Non-Patent Document 2) is used in which a line is divided into a plurality of bands (sub-spectrums), and each sub-spectrum is arranged in a vacant band that is dispersed to perform communication. As a line allocation method of such a wireless communication system, application of a line allocation method using the first fit method (Non-Patent Document 3) is considered, and this is hereinafter referred to as a conventional method.

Local Satellite Communication Organization (LASCOM): “DAMA Line Control Method”. LASCOM STD-401. Abe, Yamashita, Kobayashi: “Proposal of spectrum-editing band-distributed transmission to achieve high frequency utilization efficiency” [in Japanese], IEICE Technical Report. SAT, Satellite Communication , 109, 340, pp.7-12 (2009-12-10). Nakahira, Kobayashi, Otsuki: “Study of channel allocation algorithm for polarization-free tracking ku-band mobile satellite communication system” [in Japanese], IEICE technical report. SAT, Satellite Communication, 108, 58, pp.13-18 (2008-05-20). Abe, Nakahira, Kobayashi: “Comparative study of transmission systems using multiple bands suitable for satellite communications”, IEICE Technical Report. SAT, Satellite Communications (2011-5).

  In the conventional method, as shown in FIG. 15, a frequency fixed point (FP) is set at the lower limit frequency of the system band. At the time of line allocation, the line is divided into sub-spectrums in order from the free band closest to the FP, and the above is repeated until the total band of the arranged sub-spectrums reaches the required band required to satisfy the required speed. repeat.

  Here, in the bandwidth distributed transmission, the required bandwidth increases as the number of divisions increases even in a line having the same required speed. If the required bandwidth increases, the transmission power will increase. In addition, when the peak power changes according to the combination of the number of divisions and the division bandwidth, and the peak power exceeds the maximum transmission power of the power amplifier, nonlinear distortion occurs in the signal output from the power amplifier, and communication quality Deteriorates. On the other hand, in the conventional method, the number of divisions and the division bandwidth are determined using only the information on the free bandwidth, so that a large power amplifier corresponding to a decrease in frequency utilization efficiency due to an increase in required bandwidth or an increase in peak power is used. What is needed is a challenge.

  An object of the present application is to provide a line allocation apparatus and a line allocation method that can effectively use a system band by band-distributed transmission and reduce an increase in required band and peak power, which are problems of the conventional method.

  In order to perform band dispersion transmission in which a signal (sub-spectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band, a first invention provides a communication line for the terminal station. In the line allocating apparatus that performs allocation, a modulation slot number calculating unit that calculates the number of frequency slots represented by the number of unit frequency slots corresponding to the half-value bandwidth of the modulation signal transmitted by the terminal station, and the number of modulation slots are divided A division pattern generation unit that calculates a division pattern that is a combination of sub-spectrums, a division pattern selection unit that selects a division pattern whose peak power does not exceed the maximum transmission power of the terminal station, and a division pattern selection unit Comprises a line allocating means for allocating a communication line to a terminal station based on the division pattern selected by and the distribution of free bands.

  According to a second aspect of the present invention, in order to perform band-distributed transmission in which a signal (subspectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band, a communication line for the terminal station In the line allocating apparatus that performs allocation, a modulation slot number calculating unit that calculates the number of frequency slots represented by the number of unit frequency slots corresponding to the half-value bandwidth of the modulation signal transmitted by the terminal station, and the number of modulation slots are divided A division pattern generation unit that calculates a division pattern that is a combination of the sub-spectrums, a division pattern selection unit that selects a division pattern having the minimum peak power among the division patterns, and a division pattern selected by the division pattern selection unit Line allocating means for allocating communication lines to terminal stations based on the distribution of free bandwidth.

  According to a third aspect of the present invention, in order to perform band-distributed transmission in which a signal (subspectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band, a communication line for the terminal station In the line allocating apparatus that performs allocation, a modulation slot number calculating unit that calculates the number of frequency slots represented by the number of unit frequency slots corresponding to the half-value bandwidth of the modulation signal transmitted by the terminal station, and the number of modulation slots are divided A division pattern generation means for calculating a division pattern that is a combination of sub-spectrums, and a division pattern with the smallest number of divisions is selected from among the division patterns whose peak power does not exceed the maximum transmission power of the terminal station Select a division pattern whose peak power does not exceed the maximum transmission power of the terminal station from among division patterns with the smallest number of divisions. Comprising a dividing pattern selecting means, based on the distribution of the division pattern division pattern and available bandwidth selecting means has selected, the line allocation means for allocating the communication line to the terminal station.

  In the line allocating apparatus according to the first to third inventions, the line allocating means has a plurality of combinations of free bands in which the sub-spectrums of the divided patterns can be arranged according to the distribution of the divided patterns selected by the divided pattern selecting means and the free bands. In this case, a division pattern that minimizes the remaining free bandwidth is selected for each free bandwidth.

  According to a fourth aspect of the present invention, in order to perform band-distributed transmission in which a signal (subspectrum) divided in a frequency domain is transmitted among a plurality of terminal stations using a distributed free band, a communication line for the terminal station In the channel allocation method for allocation, a modulation slot number calculating step for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half-value bandwidth of the modulation signal transmitted by the terminal station, and dividing the number of modulation slots A division pattern generation step for calculating a division pattern that is a combination of the sub-spectrums, a division pattern selection step for selecting a division pattern whose peak power does not exceed the maximum transmission power of the terminal station, and a division pattern selection step The line allocation for allocating communication lines to terminal stations based on the division pattern selected by And a step.

  According to a fifth aspect of the present invention, in order to perform band-distributed transmission in which a signal (subspectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band, a communication line for the terminal station In the channel allocation method for allocation, a modulation slot number calculating step for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half-value bandwidth of the modulation signal transmitted by the terminal station, and dividing the number of modulation slots A division pattern generation step for calculating a division pattern that is a combination of the sub-spectrums, a division pattern selection step for selecting a division pattern having the minimum peak power among the division patterns, and a division pattern selected by the division pattern selection step A line allocation step for allocating communication lines to terminal stations based on the distribution of free bandwidth

  According to a sixth aspect of the present invention, in order to perform band-distributed transmission in which a signal (subspectrum) divided in a frequency domain is transmitted among a plurality of terminal stations using a distributed free band, a communication line for the terminal station In the channel allocation method for allocation, a modulation slot number calculating step for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half-value bandwidth of the modulation signal transmitted by the terminal station, and dividing the number of modulation slots A division pattern generation step for calculating a division pattern, which is a combination of sub-spectrums, and a division pattern with the smallest number of divisions is selected from among the division patterns whose peak power does not exceed the maximum transmission power of the terminal station A division pattern in which the peak power does not exceed the maximum transmission power of the terminal station from among the division patterns with the minimum number of divisions It has a division pattern selection step of selecting, based on the distribution of the divided patterns and available bandwidth division pattern selection step selects, and line allocation step for allocating a communication channel to the terminal station.

  In the line allocation methods of the fourth to sixth inventions, the line allocation step includes a plurality of combinations of free bands in which sub-spectrums of the division pattern can be arranged according to the distribution of the division pattern selected by the division pattern selection step and the free band. In this case, a division pattern that minimizes the remaining free bandwidth is selected for each free bandwidth.

  The present invention selects a division pattern whose peak power does not exceed the maximum transmission power of the terminal, and assigns each sub-spectrum of the selected division pattern to a free band, thereby enabling signal transmission without distortion. At the same time, it is possible to reduce the size of the power amplifier by suppressing the maximum transmission power of the terminal station.

  In addition, when allocating a line to a free band, selecting a free band that minimizes the remaining free band by allocating a sub-spectrum makes it easy to leave a wide continuous free band, making subsequent line allocation more efficient Can be done well.

It is a figure explaining the principle of band dispersion transmission. It is a flowchart which shows the line allocation processing procedure of Example 1 of this invention. It is a figure which shows the 1st selection method of a division | segmentation pattern. It is a figure which shows the example of arrangement | positioning of the sub spectrum by Best fit arrangement | positioning. It is a figure which shows the 2nd selection method of a division | segmentation pattern. It is a figure which shows the 3rd selection method of a division | segmentation pattern. It is a flowchart which shows the line allocation processing procedure of Example 2 of this invention. It is a figure which shows the 1st selection method of a division | segmentation arrangement | positioning pattern. It is a figure which shows the 2nd selection method of a division | segmentation arrangement | positioning pattern. It is a figure which shows the 3rd selection method of a division | segmentation arrangement | positioning pattern. It is a figure which shows the example of selection from the division | segmentation arrangement | positioning pattern of Best fit arrangement | positioning. It is a figure which shows the structural example of a satellite communication system. It is a figure which shows the structural example of a cellular communication system. It is a figure which shows the structural example of a line allocation apparatus. It is a figure which shows the example of the conventional line allocation.

(About the principle of circuit allocation in bandwidth distributed transmission)
As a premise for line allocation, a line is divided into frequency slots having a fixed bandwidth and controlled in units of the frequency slots. Also, the modulation scheme and error correction coding rate are fixed.

FIG. 1 shows the principle of band dispersion transmission.
The initial spectrum shown in FIG. 1 (1) is the signal shape before division necessary to achieve the required speed, and the number of modulation slots Wmod (the number of frequency slots corresponding to the half-value bandwidth of the modulation signal) and a constant band The width roll-off slot number Wroll (number of frequency slots corresponding to the occupied bandwidth minus the number of modulation slots). The initial spectrum is divided into N sub-spectrums (N is an integer of 2 or more) on the transmission side, and is synthesized into a spectrum having the same shape as the initial spectrum on the reception side.

The number of modulation slots Wmod is the required speed Rreq (bit / s), the unit bandwidth of the frequency slot is W ₀ (Hz), and the spectrum utilization efficiency (bit rate that can be transmitted per frequency) is η (bit / s / Hz). ) As follows. Here, the operator <x> returns the smallest integer greater than or equal to x.
Wmod = <Rreq / ηW ₀ > (1)

In order to synthesize sub-spectrums without deterioration, it is necessary to set the sum of adjacent sub-spectrums to 1 (flat) during synthesis. Therefore, the frequency filter is used to divide the half-value frequencies of adjacent sub-spectrums (frequency at which power is halved with respect to the center frequency). Therefore, the number of frequency slots corresponding to the occupied bandwidth of the _nth subspectrum is a value obtained by adding Wroll to the number of divided slots Wn (number of frequency slots corresponding to the half-value bandwidth of the subspectrum). In this case, the total division number of slots W _n should match the modulation slot number Wmod as follows.
Wmod = W ₁ + W ₂ + ... + W _N (2)

As described above, the required number of slots Wreq required to achieve the required speed in band dispersion transmission is expressed by the following equation, and increases according to the division number N.
_{Wreq = (W 1 + Wroll)} + ... + (W n + Wroll) = Wmod + NWroll ... (3)

(Line allocation method)
There are a plurality of combinations of the number of divided slots W _n satisfying the equation (2), and these are called divided patterns. Table 1 shows a division pattern with the number of modulation slots Wmod = 6.

In Table 1, D _x is the x-th divided patterns, W _y is the number of divided slots of y-th sub-spectrum, the numbers in the table shows the division slot number W _y in the divided pattern D _x . In band dispersion transmission, the amplitude distribution changes depending on the division pattern, and thus PAPR (peak power to average power ratio) changes (Non-Patent Document 4). Table 1 also shows an example of the relationship between the division pattern and PAPR. However, the PAPR value in Table 1 is an example for explaining the line allocation method according to the present invention, and may be different from the actual one.

When the i-th division pattern derived from the number of modulation slots Wmod is D (Wmod, i), PAPR is expressed by a function f using the division pattern as a parameter as in the following equation.
PAPR = f (D (Wmod, i)) (4)

Therefore, when the average power of the line is Pavg, the peak power Ppeak is given by the following equation, and changes according to the division pattern. Note that Pavg is determined from the required C / N (ratio of the noise power N to the received power C necessary to ensure the required bit error rate) and the required speed Rreq.
Ppeak = Pavg × PAPR = Pavg × f (D (Wmod, i)) (5)

FIG. 2 shows a line allocation processing procedure according to the first embodiment of the present invention.
In FIG. 2, in step 1, the required speed Rreq is specified, and the number of modulation slots Wmod is calculated from the required speed Rreq using equation (1). In step 2, a division pattern is derived from the number of modulation slots Wmod. In step 3, one of the divided patterns is selected, and each sub-spectrum is arranged in an empty band. If each sub-spectrum of the selected division pattern cannot be arranged in the free band, the next division pattern is selected.

  Here, there are the following three methods for selecting one division pattern in step 3 from the division pattern obtained in step 2.

(First selection method)
FIG. 3 shows a first division pattern selection method. In this example, the number of modulation slots is calculated as Wmod = 12, and six types of division patterns are derived.

  In the first selection method, among six types of division patterns, a division pattern (5 types) satisfying peak power ≦ maximum transmission power is selected, and an arbitrary one is selected (hereinafter referred to as a selection pattern). The sub-spectrum of the selected pattern is arranged in the free band. If all the sub-spectrums of the selected pattern cannot be arranged in the free band in the system band, this operation is repeated until the next selected pattern can be arranged.

  Conventionally, a terminal requires a high-power power amplifier so that the maximum transmission power is not insufficient even for a pattern having the largest PAPR among all possible division patterns. On the other hand, in the present invention, since one of the division patterns satisfying peak power ≦ maximum transmission power is selected and line allocation is performed, signal transmission without distortion is possible without using a high power power amplifier. The amplifier can be reduced in size.

  Here, when there are a plurality of vacant band candidates that can be arranged for the a-th sub-spectrum of the selected pattern, after the a-th sub-spectrum is arranged in the b-th vacant band, it remains in the b-th vacant band. May be arranged in a candidate having the smallest number of consecutive empty slots on the frequency axis (hereinafter referred to as “best fit arrangement”).

FIG. 4 shows an example of sub-spectrum arrangement by the best fit arrangement.
In FIG. 4, the number of modulation slots included in each of the sub-spectrums 1 and 2 of the selected pattern is 3 and 6, and the number of empty slots included in each of the empty bands A, B, C, and D is 3, 5, and 6, respectively. , 15. In the best fit arrangement, first, since the number of modulation slots included in sub-spectrum 1 and the number of empty slots included in free band A are the same (= 3), sub-spectrum 1 is assigned to free band A. Next, since the number of modulation slots included in sub-spectrum 2 and the number of empty slots included in free band C are the same (= 6), sub-spectrum 2 is assigned to free band C.

  On the other hand, in the case of random arrangement, for example, if sub spectrum 1 is assigned to empty band B, the number of empty slots 2 remains, and if sub spectrum 2 is appropriately assigned to empty band D, the number of empty slots 2 and 7 remains. Thus, it can be seen that the Best fit arrangement can secure a wide continuous free band by leaving the free band D as it is after the arrangement. Therefore, it is possible to reduce the probability that the subsequent sub-spectrum cannot be arranged and increase the effect of the present invention.

(Second selection method)
FIG. 5 shows a second method for selecting a division pattern. In this example, the number of modulation slots is calculated as Wmod = 12, and six types of division patterns are derived.

  In the second selection method, one of the division patterns having the minimum peak power is selected from the six types of division patterns. If there is no candidate free band that can be placed, the one with the next smallest peak power is selected and this operation is repeated until placement is possible. As a result, line allocation that is the minimum peak power is always performed in the arrangementable division patterns, so that the average value of the peak power can be reduced. When combined with a power amplifier that can control the maximum transmission power by changing the operating point, the average transmission power of the terminal can be suppressed by controlling the maximum transmission power according to the peak power of the assigned line. it can.

(Third selection method)
FIG. 6 shows a third method for selecting a division pattern. In this example, the number of modulation slots is calculated as Wmod = 12, and six types of division patterns are derived.

  In the third selection method, as shown in FIG. 6 (1), among the six types of division patterns, the division number N (required slot number Wreq) is the smallest among the division patterns having peak power ≦ maximum transmission power. Select what will be. If there is no candidate free band that can be arranged, the one with the next smallest division number N is selected, and this operation is repeated until it can be arranged. Alternatively, as shown in FIG. 6 (2), one having the smallest number of divisions N (required slot number Wreq) is selected from among the division patterns, and any one division in which peak power ≦ maximum transmission power is selected. A pattern may be selected. Thereby, in addition to the effect of the first selection method, it is possible to perform line allocation with a small required number of slots Wreq (high frequency utilization efficiency).

As shown in FIG. 4, there are a plurality of arrangement patterns even in the same division pattern. Therefore, the j-th arrangement pattern of the i-th division pattern having the modulation slot number Wmod is D (Wmod, i, j), and each is referred to as a division arrangement pattern. Here, it is assumed that the relationship between the divided arrangement pattern and the PAPR is expressed by a function g as in the following equation.
PAPR = g (D (Wmod, i, j)) (6)

FIG. 7 shows a line allocation processing procedure according to the second embodiment of the present invention.
In FIG. 7, in step 1, the required speed Rreq is specified, and the number of modulation slots Wmod is calculated from the required speed Rreq using equation (1). In step 2, a divided arrangement pattern is derived from the number of modulation slots Wmod. In step 3, one of the divided arrangement patterns is selected, and the sub-spectrum is arranged in an empty band. Since the present embodiment is a divided arrangement pattern in which the divided pattern and the arrangement pattern are combined, unlike the first embodiment in which selection is made from the division pattern, the arrangement in the free band is completed with one selection.

  Here, the method for selecting one divided arrangement pattern in step 3 from the divided arrangement pattern obtained in step 2 is the following three methods as in the first embodiment.

  As shown in FIG. 8, the first selection method is to select an arbitrary one from among five types of divided arrangement patterns, and a sub-spectrum of the selected arrangement pattern. Is placed in a free band. In FIG. 8, arrows indicate each sub-spectrum of the arrangement selection pattern. A broken line indicates an empty band, and hatching indicates an existing line. The same applies to FIGS. 9 to 11 described below.

  As shown in FIG. 9, the second selection method selects a pattern having the minimum peak power among the five types of divided arrangement patterns.

  As shown in FIG. 10, the third selection method is one in which the division number N (required slot number Wreq) is the smallest among the division arrangement patterns in which the peak power ≦ the maximum transmission power among the five types of division patterns. Select.

  Further, as shown in FIG. 11, as long as the divided arrangement pattern is the best fit arrangement, the selection method may be selected from among them.

  In the above description, when the number of divided patterns and divided arrangement patterns becomes enormous and it is difficult to obtain all of them, a part of the divided patterns and divided arrangement patterns may be obtained and the method of the present invention may be used. Further, the spectrum use efficiency and the required C / N value can be changed by the communication method (combination of modulation method and error correction coding rate). Therefore, a division pattern or a division arrangement pattern may be obtained for each communication method, and the method of the present invention may be used.

  In the satellite communication system shown in FIG. 12, the node station is a communication satellite, and in the cellular communication system shown in FIG. 13, the node station is a cellular base station. The terminal station is notified of the line assigned from the line assignment apparatus via the control line from the node station, and performs wireless communication with another terminal station via the node station using the line.

  Here, the line allocating device needs to grasp information composed of (1) selectable communication methods, (2) maximum transmission power, and (3) required speed for each terminal station. Since (1) and (2) are information specific to the terminal station that can be known in advance, the information is stored in the terminal management DB unit of the line allocation apparatus in association with the terminal station ID information. On the other hand, (3) differs for each line request. Therefore, the terminal station gives the terminal station ID information and the requested speed to the line request signal and transmits it to the line allocating device using the control line.

FIG. 14 shows a configuration example of the line allocation device.
In FIG. 14, the line allocation device is configured by a control line transmission / reception unit 11, an access control unit 12, a terminal management DB unit 13, a line management DB unit 14, and a line allocation processing unit 15. When the control line transmission / reception unit 11 receives the line request signal, the access control unit 12 extracts the terminal station ID and the requested speed, and notifies the line allocation processing unit 15 of the terminal station ID and the requested speed. The line allocation processing unit 15 uses the line allocation method of the present invention to divide the requested rate from the requested rate, the free bandwidth information of the line management DB unit 14 and the terminal information of the terminal management DB unit 13. Depending on the pattern or division arrangement pattern, (a) the number of divisions (number of sub-spectrums), (b) the number of modulation slots that make up each sub-spectrum, and (c) the line element consisting of the center frequency of each sub-spectrum. The line element is returned to the terminal station having the terminal station ID, and the contents of the line management DB unit 14 are updated. On the other hand, when the communication is completed, the terminal station assigns the terminal station ID to the line open signal and transmits it to the line allocation device using the control line. In the line allocation device, when the control line transmission / reception unit 11 receives the line release signal, the access control unit 12 extracts the terminal station ID and deletes the contents of the allocated line from the line management DB unit 13.

DESCRIPTION OF SYMBOLS 11 Control line transmission / reception part 12 Access control part 13 Terminal management DB part 14 Line management DB part 15 Line allocation process part

Claims (8)

A line allocating apparatus for allocating a communication line to a terminal station in order to perform band distributed transmission in which a signal (sub-spectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band. In
Modulation slot number calculating means for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half bandwidth of the modulation signal transmitted by the terminal station;
Division pattern generation means for calculating a division pattern that is a combination of sub-spectrums obtained by dividing the number of modulation slots;
Of the division patterns, a division pattern selection means for selecting a division pattern whose peak power does not exceed the maximum transmission power of the terminal station;
A line allocating apparatus comprising: a line allocating unit that allocates a communication line to the terminal station based on the division pattern selected by the division pattern selecting unit and the distribution of the free band. A line allocating apparatus for allocating a communication line to a terminal station in order to perform band distributed transmission in which a signal (sub-spectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band. In
Modulation slot number calculating means for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half bandwidth of the modulation signal transmitted by the terminal station;
Division pattern generation means for calculating a division pattern that is a combination of sub-spectrums obtained by dividing the number of modulation slots;
Of the division patterns, a division pattern selection means for selecting a division pattern having a minimum peak power;
A line allocating apparatus comprising: a line allocating unit that allocates a communication line to the terminal station based on the division pattern selected by the division pattern selecting unit and the distribution of the free band. A line allocating apparatus for allocating a communication line to a terminal station in order to perform band distributed transmission in which a signal (sub-spectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band. In
Modulation slot number calculating means for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half bandwidth of the modulation signal transmitted by the terminal station;
Division pattern generation means for calculating a division pattern that is a combination of sub-spectrums obtained by dividing the number of modulation slots;
Among the division patterns, the division pattern with the smallest number of divisions is selected from the division patterns whose peak power does not exceed the maximum transmission power of the terminal station, or the peak power is selected from among the division patterns with the smallest number of divisions. Division pattern selection means for selecting a division pattern that does not exceed the maximum transmission power of the terminal station,
A line allocating apparatus comprising: a line allocating unit that allocates a communication line to the terminal station based on the division pattern selected by the division pattern selecting unit and the distribution of the free band. In the line allocating device according to any one of claims 1 to 3,
The line allocating unit remains for each free band when there are a plurality of combinations of free bands in which the sub-spectrum of the division pattern can be arranged according to the distribution of the division pattern selected by the division pattern selection unit and the free band. A line allocating device that selects a division pattern that minimizes an available bandwidth. A line allocation method for allocating a communication line to a terminal station in order to perform band distributed transmission in which a signal (sub-spectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band. In
A modulation slot number calculating step for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half bandwidth of the modulation signal transmitted by the terminal station;
A division pattern generation step of calculating a division pattern that is a combination of sub-spectrums obtained by dividing the number of modulation slots;
Of the division patterns, a division pattern selection step of selecting a division pattern whose peak power does not exceed the maximum transmission power of the terminal station;
A line assignment method comprising: a line assignment step for assigning a communication line to the terminal station based on the division pattern selected in the division pattern selection step and the distribution of the free band. A line allocation method for allocating a communication line to a terminal station in order to perform band distributed transmission in which a signal (sub-spectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band. In
A modulation slot number calculating step for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half bandwidth of the modulation signal transmitted by the terminal station;
A division pattern generation step of calculating a division pattern that is a combination of sub-spectrums obtained by dividing the number of modulation slots;
Of the division patterns, a division pattern selection step for selecting a division pattern having a minimum peak power;
A line assignment method comprising: a line assignment step for assigning a communication line to the terminal station based on the division pattern selected in the division pattern selection step and the distribution of the free band. A line allocation method for allocating a communication line to a terminal station in order to perform band distributed transmission in which a signal (sub-spectrum) divided in a frequency domain is transmitted between a plurality of terminal stations using a distributed free band. In
A modulation slot number calculating step for calculating the number of frequency slots represented by the number of unit frequency slots corresponding to the half bandwidth of the modulation signal transmitted by the terminal station;
A division pattern generation step of calculating a division pattern that is a combination of sub-spectrums obtained by dividing the number of modulation slots;
Among the division patterns, the division pattern with the smallest number of divisions is selected from the division patterns whose peak power does not exceed the maximum transmission power of the terminal station, or the peak power is selected from among the division patterns with the smallest number of divisions. A division pattern selection step of selecting a division pattern that does not exceed the maximum transmission power of the terminal station,
A line assignment method comprising: a line assignment step for assigning a communication line to the terminal station based on the division pattern selected in the division pattern selection step and the distribution of the free band. In the line allocation method according to any one of claims 5 to 7,
The line allocating step remains for each free band when there are a plurality of combinations of free bands in which the sub-spectrum of the division pattern can be arranged according to the distribution of the division pattern selected by the division pattern selection step and the free band. A circuit allocation method characterized by selecting a division pattern that minimizes the available bandwidth.

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