JP6671689B2 - Line assignment apparatus and line assignment method - Google Patents

Description

  The present invention provides a wireless communication system in which a terminal station communicates via a communication satellite or a cellular base station for mobile communication (hereinafter, referred to as a "node station"). And a line allocating method for transmitting data.

  FIG. 3 is a wireless communication system using a communication satellite as a node station, and FIG. 4 is a wireless communication system using a cellular base station as a node station. The terminal station is notified of the line allocated from the line allocating device via the control line from the node station, and performs wireless communication with another terminal station via the node station using the line.

  In such a wireless communication system, the total bandwidth of the line allocated to each terminal station is limited to a system bandwidth available to the node station or less. In the demand assignment method used to effectively use the system bandwidth, a line is dynamically allocated to the terminal station that starts communication and the line is released at the end of communication, but each terminal station asynchronously allocates and releases the line. Because of the repetition, a plurality of free bands are generated on the system band. Therefore, a band division transmission that divides a continuous frequency band of a spectrum into a plurality of bands (sub-spectrums), arranges each sub-spectrum in a dispersed free band, transmits the sub-spectrum, and restores the original continuous band on a receiving side. (Patent Document 1). Also, there is band compression transmission in which a part of the spectrum band is deleted and transmitted, and the band deleted on the receiving side is restored (Non-Patent Document 1). It is also possible to combine this band compression transmission and band division transmission, and this is called band compression division transmission.

FIG. 5 shows the principle of band compression division transmission.
In FIG. 5, an initial spectrum is a signal shape required to achieve a required speed, and includes an initial modulation slot number Wmod0 (the number of frequency slots corresponding to a half bandwidth of a modulation signal) and a roll-off slot having a fixed bandwidth. The number Wroll (the number obtained by subtracting the number of modulation slots from the number of frequency slots corresponding to the occupied bandwidth). The transmitting side divides into N (N is an integer of 2 or more) sub-spectrums for the number Wmod of compression modulation slots after band compression for removing a part of the band from the initial spectrum, and transmits. On the receiving side, the divided bands are combined, and the deleted bandwidth is restored by band equalization processing, thereby obtaining a spectrum having the same shape as the initial spectrum.

  A conventional channel allocation method (first fit method) performed by the channel allocation device shown in FIGS. 3 and 4 in a wireless communication system using such band compression division transmission will be described with reference to FIG.

  In FIG. 6, when the total available bandwidth is small with respect to the line bandwidth (the number of initial modulation slots) that satisfies the required speed, bandwidth compression for deleting a part of the line bandwidth is performed. A frequency fixed point (FP) is set at the lower limit frequency of the system band. The line allocation is performed by dividing the band-compressed line into sub-spectrums in order from the free band closest to the FP, and until the total band of the arranged sub-spectrum reaches the compression band (the number of compression modulation slots). Is repeated. Here, an example of three divisions is shown.

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

FIG. 7 shows a configuration example of a line assignment device.
7, the line allocation device includes a control line transmitting / receiving 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 transmitting / receiving 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. The line allocation processing unit 15 calculates (a) the compression ratio, (b) the number of divisions (the number of sub-spectrums) from the requested speed, the information on the available bandwidth in the line management DB unit 14, and the terminal information in the terminal management DB unit 13. ), (C) the number of modulation slots constituting each sub-spectrum, (d) the line element consisting of the center frequency of each sub-spectrum is determined, the line element is returned to the terminal station having the terminal station ID, and the line management DB The contents of the unit 14 are updated. The line management DB unit 14 stores, for each terminal station in communication, information on the center frequency of one or more sub-spectrums in use and the number of frequency slots corresponding to the occupied bandwidth in association with the terminal ID. .

  On the other hand, when the communication is completed, the terminal station assigns the terminal station ID to the line release signal and transmits the signal to the line allocation device using the control line. In the line allocating apparatus, when the control line transmitting / receiving 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 14.

Japanese Patent No. 5483472

Masuno, Sugiyama: "R & D of Spectrum-Suppressed Wireless Transmission Technology to Increase Frequency Efficiency," NTT Technical Journal, Vol.23, No.11, pp.38-41 (November 2011).

  In band compression division transmission, the required band increases as the number of divisions increases, even for lines having the same request speed. If the required bandwidth increases, the transmission power will increase. In addition, the peak power changes according to the combination of the number of divisions and the divided bandwidth, and further, the peak power changes according to the band compression ratio, which is the ratio of the bandwidth before and after the band compression, and the frequency position of the deleted band. If 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, since the number of divisions and the division bandwidth are determined using only the information on the free band, a high power amplifier corresponding to a decrease in the frequency use efficiency due to an increase in the required band and an increase in the peak power. Is required.

  On the other hand, a line allocation method that satisfies the required speed of the terminal station, suppresses the maximum transmission power and power consumption, and effectively uses the bandwidth available in the entire system in consideration of the combination of the number of divisions and the divided bandwidth is patented. It is disclosed in reference 1. However, Patent Document 1 does not assume control in consideration of the band compression ratio.

  SUMMARY OF THE INVENTION It is an object of the present invention to provide a line allocating apparatus and a line allocating method capable of reducing a required band and an increase in peak power while effectively utilizing a system band by band compression division transmission.

According to a first aspect of the present invention, in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain between a plurality of terminal stations by using dispersed free bands, a communication line for the terminal station is provided. In the line allocating device for performing the allocation, the number of initial modulation slots expressed in units of modulation slots having a constant bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station is calculated. the compression modulation slot number calculating means for calculating the number of compression modulation slots compressed in accordance with the bandwidth compression ratio for each of the plurality of bandwidth compression ratio, the compressed division pattern is a combination of sub-spectrum obtained by dividing the number of compression modulation slots a compressed division pattern generating means for calculating by a plurality of types, all compressed division pattern obtained by a plurality of types for each of the plurality of bandwidth compression ratio From down, out of the compressed division pattern can be placed in the free zone, the compressed division pattern selecting means for peak power selects one compressed division pattern does not exceed the maximum transmit power of the terminal station, compressed division pattern selecting means selects A line allocating unit for allocating a communication line to the terminal station based on the compression division pattern and the distribution of the available bandwidth.

According to a second aspect of the present invention, in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain between a plurality of terminal stations by using dispersed free bands, a communication line for the terminal station is provided. In the line allocating device for performing the allocation, the number of initial modulation slots expressed in units of modulation slots having a constant bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station is calculated. the compression modulation slot number calculating means for calculating the number of compression modulation slots compressed in accordance with the bandwidth compression ratio for each of the plurality of bandwidth compression ratio, the compressed division pattern is a combination of sub-spectrum obtained by dividing the number of compression modulation slots a compressed division pattern generating means for calculating by a plurality of types, all compressed division pattern obtained by a plurality of types for each of the plurality of bandwidth compression ratio From down, out of the compressed division pattern can be placed in the free zone, the compressed division pattern selecting means for selecting one compression division pattern peak power is minimized, compressed division pattern and available bandwidth compressed division pattern selecting means selects Line allocation means for allocating communication lines to terminal stations based on the distribution of

According to a third aspect of the present invention, in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain between a plurality of terminal stations by using dispersed free bands, a communication line for the terminal station is used. In the line allocating device for performing the allocation, the number of initial modulation slots expressed in units of modulation slots having a constant bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station is calculated. the compression modulation slot number calculating means for calculating the number of compression modulation slots compressed in accordance with the bandwidth compression ratio for each of the plurality of bandwidth compression ratio, the compressed division pattern is a combination of sub-spectrum obtained by dividing the number of compression modulation slots a compressed division pattern generating means for calculating by a plurality of types, all compressed division pattern obtained by a plurality of types for each of the plurality of bandwidth compression ratio From down, out of the compressed division pattern can be placed in the free zone, the division number from the compressed division pattern selects one compressed division pattern which minimizes the peak power does not exceed the maximum transmit power of the terminal station, or divided A compression division pattern selecting means for selecting one compression division pattern whose peak power does not exceed the maximum transmission power of the terminal station from among the compression division patterns having the minimum number, a compression division pattern selected by the compression division pattern selection means; A line allocating unit for allocating a communication line to the terminal station based on the distribution of the available bandwidth.

According to a fourth aspect of the present invention, in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain between a plurality of terminal stations by using dispersed free bands, a communication line for the terminal station is used. In the line allocation method for performing the allocation, the terminal station calculates the number of initial modulation slots expressed in units of modulation slots having a constant bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots by a plurality. A compression modulation slot number calculation step of calculating the number of compression modulation slots compressed according to the band compression ratio , and a compression division pattern that is a combination of sub-spectrum obtained by dividing the number of compression modulation slots for each of a plurality of band compression ratios. a compressed division pattern generation step of calculating by a plurality of types, all obtained by a plurality of types for each of the plurality of bandwidth compression ratio compression From split pattern of the compressed division pattern can be placed in the free zone, the compressed division pattern selection step of peak power to select one compression division pattern does not exceed the maximum transmit power of the terminal station, compressed division pattern selecting step selects And a line allocating step of allocating a communication line to a terminal station based on the compressed division pattern and the distribution of available bandwidth.

According to a fifth aspect of the present invention, in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain between a plurality of terminal stations by using dispersed free bands, a communication line for the terminal station is provided. In the line allocation method for performing the allocation, the terminal station calculates the number of initial modulation slots expressed in units of modulation slots having a constant bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots by a plurality. A compression modulation slot number calculation step of calculating the number of compression modulation slots compressed according to the band compression ratio , and a compression division pattern that is a combination of sub-spectrum obtained by dividing the number of compression modulation slots for each of a plurality of band compression ratios. a compressed division pattern generation step of calculating by a plurality of types, all obtained by a plurality of types for each of the plurality of bandwidth compression ratio compression From split pattern of the compressed division pattern can be placed in the free zone, the compressed division pattern selection step of peak power to select one compression division pattern having the minimum, compressed division pattern and free of compressed division pattern selecting step selects A line allocating step of allocating a communication line to the terminal station based on the distribution of the band.

According to a sixth aspect of the present invention, in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain between a plurality of terminal stations by using dispersed free bands, a communication line for the terminal station is provided. In the line allocation method for performing the allocation, the terminal station calculates the number of initial modulation slots expressed in units of modulation slots having a constant bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots by a plurality. A compression modulation slot number calculation step of calculating the number of compression modulation slots compressed according to the band compression ratio , and a compression division pattern that is a combination of sub-spectrum obtained by dividing the number of compression modulation slots for each of a plurality of band compression ratios. a compressed division pattern generation step of calculating by a plurality of types, all obtained by a plurality of types for each of the plurality of bandwidth compression ratio compression From split pattern of the compressed division pattern can be placed in the free zone, the number of division selects one compressed division pattern having the minimum from among the compressed division pattern peak power does not exceed the maximum transmit power of the terminal station, or A compression division pattern selection step of selecting one compression division pattern whose peak power does not exceed the maximum transmission power of the terminal station from among the compression division patterns having the minimum number of divisions, and a compression division pattern selected by the compression division pattern selection step And allocating a communication line to the terminal station based on the distribution of the available bandwidth.

  ADVANTAGE OF THE INVENTION According to this invention, while satisfying | requiring the speed | rate of a terminal station, it is possible to perform channel allocation in consideration of the reduction of the maximum transmission power and the amount of power consumption of the terminal station, and it is possible to effectively use the bandwidth of the entire system.

It is a flowchart which shows the example of a line allocation processing procedure in this invention. It is a figure showing the 1st selection method of a compression division pattern. It is a figure showing the example of composition of a satellite communication system. FIG. 1 is a diagram illustrating a configuration example of a cellular communication system. FIG. 3 is a diagram illustrating the principle of band compression division transmission. FIG. 10 is a diagram illustrating a conventional line assignment example. It is a figure showing the example of composition of a circuit allotment device.

  In the present invention, as a premise of channel allocation, a channel is divided into frequency slots having a fixed bandwidth, and control is performed in units of the frequency slots. Further, the modulation scheme and the error correction coding rate are fixed.

  There are a plurality of combinations of the number of modulation slots obtained by dividing the transmission spectrum band-compressed at a plurality of band compression ratios, and this is called a compression division pattern. Table 1 shows that, when the total number of slots in the free band is 6 and the band compression is necessary for the initial modulation slot number Wmod0 = 8 that satisfies the required speed, the band compression ratio r = 6/8 or less A compression division pattern with a ratio r = 6/8 and the number of compression modulation slots Wmod = 6, a compression division pattern with a band compression ratio r = 5/8 and a number of compression modulation slots Wmod = 5, and a band compression ratio r = 4/8 , And the number of compression modulation slots Wmod = 4.

  Assuming a continuous free band, a compression division pattern (division number 1) which is not divided by the number of compression modulation slots Wmod = 6, 5, 4 may be added.

  In Table 1, D (Wmod, r, i) is the i-th compression division pattern of the number of compression modulation slots Wmod and the band compression ratio r, and Wj is the j-th divided subspectrum (division slot). , The numbers in the table indicate the number of modulation slots of the division slot Wj in the compression division pattern D (Wmod, r, i). For example, D (6, r, 5) is obtained by dividing the number Wmod = 6 of compressed modulation slots subjected to band compression at a band compression ratio r = 6/8 by the number of modulation slots 1, 1, and 4. (The required number of slots) is 3.

In band compression division transmission, since the amplitude distribution changes depending on the band compression ratio, the number of divisions, and the compression division pattern D (Wmod, r, i) corresponding to the number of modulation slots in each division slot, PAPR (peak power to average power ratio) Changes. That is, the PAPR is represented by a function f having the compression division pattern D (Wmod, r, i) as a parameter.
PAPR = f (D (Wmod, r, i)) (1)

When the average power of the line is Pavg, the peak power Ppeak is given by the following equation, which changes according to the compression division pattern. Pavg is determined from the required C / N (the ratio of the noise power N to the received power C required to secure the required bit error rate) and the required speed Rreq.
Ppeak = Pavg x PAPR
= Pavg × f (D (Wmod, r, i)) (2)

  In Table 1, the value of PAPR in each compression division pattern is omitted, but the values of PAPR and peak power differ according to the compression division pattern D (Wmod, r, x).

Further, the value of PAPR differs for each compression division pattern according to the frequency band to be deleted as described below.
a: Compresses the low frequency side of the band b: Compresses the intermediate frequency of the band c: Compresses the high frequency side of the band d: a + b (when compressing two or more modulation slots)
e: b + c (when compressing 2 modulation slots or more)
f: a + c (when compressing 2 modulation slots or more)
g: a + b + c (when compressing three or more modulation slots)

  In the compression division pattern in Table 1, it is assumed that a pattern having the minimum PAPR is selected from the compression bands a to g. At this time, the PAPR of each compression division pattern including the compression bands a to g may be actually measured, and the compression division pattern having the minimum PAPR value may be selected.

FIG. 1 shows an example of a line allocation processing procedure in the present invention.
In FIG. 1, in step 1, a request rate is specified, and the number of initial modulation slots Wmod0 that satisfies the request rate and the number of compression modulation slots Wmod corresponding to a plurality of band compression ratios r up to the total number of available bandwidths are determined. calculate. In step 2, a compression division pattern as shown in Table 1 is derived from the number of compression modulation slots Wmod for each band compression ratio r. In step 3, one of the compression division patterns is selected, and each sub-spectrum is allocated to a free band. If each sub-spectrum of the selected compression division pattern cannot be allocated to an empty band, the next compression division pattern is selected.

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

(First selection method)
FIG. 2 shows a first method of selecting a compression division pattern. Here, a part of the band compression ratio r: 6/8 and the compression division pattern of 5/8 in the examples shown in Table 1 are reproduced.

  The first selection method selects an arbitrary one of a plurality of types of compression division patterns satisfying peak power ≦ maximum transmission power from among a plurality of types of compression division patterns for each band compression ratio as shown in Table 1 (hereinafter, referred to as “the maximum transmission power”) , A selection pattern), and determine whether the sub-spectrum of the selection pattern can be allocated to a free band within the system band. If all the sub-spectrums of the selected pattern cannot be arranged in the free band, the next selection pattern is selected and this operation is repeated until the sub-spectrum can be arranged (First fit arrangement).

  In the example shown in FIG. 2 in which the total number of free bandwidth slots is 6, and the free bandwidth is divided into 3 slots and 3 slots, among the compression division patterns of the band compression ratio r: 6/8, 5/8,. , One of the compression division patterns that satisfies peak power ≦ maximum transmission power. At this time, if the selection pattern cannot be arranged in the free band, the selection is disabled, and the selection pattern is replaced until the selection pattern can be arranged in the free band, and the selection ends when the arrangement becomes possible. For example, the compression division patterns (1, 5) and (2, 4) having a band compression ratio of 6/8 cannot be arranged, but the compression division patterns (3, 3) can be arranged. Of the compression division patterns with a band compression ratio of 5/8, other than (1, 4) can be arranged. When a compression division pattern with a band compression ratio of 5/8 is selected, one slot remains empty.

  Conventionally, a terminal needs a high-power amplifier so that the maximum transmission power does not become insufficient even for the pattern having the largest PAPR among all the assumed division patterns. On the other hand, in the present invention, one of the compression division patterns that satisfies peak power ≦ maximum transmission power is selected and the channel is allocated, so that signal transmission without distortion can be performed without using a high-power power amplifier. The size of the power amplifier can be reduced.

  Here, when there are a plurality of candidates for the vacant band that can be arranged for the a-th sub-spectrum of the selection pattern, after the a-th sub-spectrum is arranged in the b-th vacant band, the remaining band remains in the b-th vacant band. (The best fit arrangement, see Patent Document 1).

(Second selection method)
In the second selection method, one of the compression division patterns having the minimum peak power is selected from a plurality of types of compression division patterns for each band compression ratio as shown in Table 1. If the allocation is not possible for the vacant band, the one with the next lowest peak power is selected and this operation is repeated until the allocation is possible.

  In the example shown in FIG. 2 in which the total number of free bandwidth slots is 6, and the free bandwidth is divided into 3 slots and 3 slots, among the compression division patterns of the band compression ratio r: 6/8, 5/8,. , A compression division pattern with the minimum peak power, for example, a compression division pattern (1, 5) with a band compression ratio r: 6/8 is selected. At this time, since it is impossible to arrange in a free band, the compression division pattern having the next lowest peak power is sequentially selected, and the selection is terminated when the arrangement becomes possible.

  As a result, the line allocation with the minimum peak power is always performed in the compressible division pattern that can be arranged, so that the average value of the peak power can be reduced. By combining with a power amplifier that can control the maximum transmission power by changing the operating point, it is possible to control the average power consumption of the terminal by controlling the maximum transmission power according to the peak power of the allocated line. it can.

(Third selection method)
According to the third selection method, among a plurality of types of compression division patterns for each band compression ratio as shown in Table 1, the number of divisions (the number of required slots) is the smallest among compression division patterns in which peak power ≦ maximum transmission power. Select the one that becomes If the allocation is not possible for the free bandwidth, the next smaller division number is selected and this operation is repeated until the allocation can be performed. Alternatively, one having a minimum number of divisions (the number of required slots) is selected from among a plurality of types of compression division patterns for each band compression ratio, and any one compression division pattern satisfying peak power ≦ maximum transmission power is selected from among them. select. If the allocation is not possible for the available bandwidth, the next compression division pattern is selected. If there is no compression division pattern having the smallest number of divisions that can be arranged, the number of divisions is increased by one until the arrangement is possible. Repeat this operation.

  In the example shown in FIG. 2 in which the total number of free bandwidth slots is 6, and the free bandwidth is divided into 3 slots and 3 slots, among the compression division patterns of the band compression ratios: 6/8, 5/8,. As a compression division pattern in which peak power ≦ maximum transmission power and the number of divisions is the minimum, compression division patterns (1, 5), (2, 4), and (3, 3) with a band compression ratio of 6/8; Compression division patterns (1, 4) and (2, 3) having a band compression ratio of 5/8 are candidates. Here, any one of the compression division patterns (3, 3) and (2, 3) that can be arranged in the free band may be selected. Furthermore, a compression division pattern that minimizes the peak power may be selected from among them.

  Thereby, in addition to the effect of the first selection method, it is possible to perform line allocation with a small number of divisions (the number of required slots), that is, with high frequency use efficiency.

  The above-described line allocation device that selects and allocates a compression division pattern can be realized by a computer and a program. This program can be stored in a computer-readable storage medium or can be provided via a network.

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 processing part

Claims (6)

A line allocating device for allocating a communication line to a plurality of terminal stations in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain using a dispersed free band among a plurality of terminal stations. At
The terminal station calculates the number of initial modulation slots expressed in units of modulation slots of a fixed bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots according to a plurality of band compression ratios. Compression modulation slot number calculation means for calculating the number of compressed compression modulation slots,
For each of the plurality of band compression ratios , a compression division pattern generation unit that calculates a plurality of types of compression division patterns that are combinations of sub-spectrums obtained by dividing the number of compression modulation slots,
From all the compression division patterns obtained by a plurality of types for each of the plurality of band compression ratios, among the compression division patterns that can be arranged in the free band, compression in which the peak power does not exceed the maximum transmission power of the terminal station. Compression division pattern selection means for selecting one division pattern;
A circuit allocating unit for allocating a communication line to the terminal station based on the compression division pattern selected by the compression division pattern selection unit and the distribution of the available bandwidth. A line allocating device for allocating a communication line to a plurality of terminal stations in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain using a dispersed free band among a plurality of terminal stations. At
The terminal station calculates the number of initial modulation slots expressed in units of modulation slots of a fixed bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots according to a plurality of band compression ratios. Compression modulation slot number calculation means for calculating the number of compressed compression modulation slots,
For each of the plurality of band compression ratios , a compression division pattern generation unit that calculates a plurality of types of compression division patterns that are combinations of sub-spectrums obtained by dividing the number of compression modulation slots,
From all of the compressed division pattern obtained by a plurality of types for each of the plurality of the bandwidth compression ratio, of the compressed division pattern positionable on the free bandwidth, selects one compressed division pattern peak power is minimized Compression division pattern selection means,
A circuit allocating unit for allocating a communication line to the terminal station based on the compression division pattern selected by the compression division pattern selection unit and the distribution of the available bandwidth. A line allocating device for allocating a communication line to a plurality of terminal stations in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain using a dispersed free band among a plurality of terminal stations. At
The terminal station calculates the number of initial modulation slots expressed in units of modulation slots of a fixed bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots according to a plurality of band compression ratios. Compression modulation slot number calculation means for calculating the number of compressed compression modulation slots,
For each of the plurality of band compression ratios , a compression division pattern generation unit that calculates a plurality of types of compression division patterns that are combinations of sub-spectrums obtained by dividing the number of compression modulation slots,
From all the compression division patterns obtained by a plurality of types for each of the plurality of band compression ratios, among the compression division patterns that can be arranged in the free band, compression in which the peak power does not exceed the maximum transmission power of the terminal station. Select one compression division pattern with the minimum number of divisions from among the division patterns, or select a compression division pattern whose peak power does not exceed the maximum transmission power of the terminal station from among the compression division patterns with the minimum number of divisions Compression division pattern selection means for selecting one ;
A circuit allocating unit for allocating a communication line to the terminal station based on the compression division pattern selected by the compression division pattern selection unit and the distribution of the available bandwidth. A line allocation method for allocating a communication line to a plurality of terminal stations in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain using a dispersed free band among a plurality of terminal stations. At
The terminal station calculates the number of initial modulation slots expressed in units of modulation slots of a fixed bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots according to a plurality of band compression ratios. A compression modulation slot number calculating step of calculating the number of compressed modulation modulation slots,
A compression division pattern generation step of calculating a plurality of types of compression division patterns each of which is a combination of sub-spectrum obtained by dividing the number of compression modulation slots , for each of the plurality of band compression ratios;
From all the compression division patterns obtained by a plurality of types for each of the plurality of band compression ratios, among the compression division patterns that can be arranged in the free band, compression in which the peak power does not exceed the maximum transmission power of the terminal station. A compression division pattern selection step of selecting one division pattern;
A line allocation step of allocating a communication line to the terminal station based on the compression division pattern selected by the compression division pattern selection step and the distribution of the available bandwidth. A line allocation method for allocating a communication line to a plurality of terminal stations in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain using a dispersed free band among a plurality of terminal stations. At
The terminal station calculates the number of initial modulation slots expressed in units of modulation slots of a fixed bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots according to a plurality of band compression ratios. A compression modulation slot number calculating step of calculating the number of compressed modulation modulation slots,
A compression division pattern generation step of calculating a plurality of types of compression division patterns each of which is a combination of sub-spectrum obtained by dividing the number of compression modulation slots , for each of the plurality of band compression ratios;
From all of the compressed division pattern obtained by a plurality of types for each of the plurality of the bandwidth compression ratio, of the compressed division pattern positionable on the free bandwidth, selects one compressed division pattern peak power is minimized A compression division pattern selection step;
A line allocation step of allocating a communication line to the terminal station based on the compression division pattern selected by the compression division pattern selection step and the distribution of the available bandwidth. A line allocation method for allocating a communication line to a plurality of terminal stations in order to perform band division transmission for transmitting a signal (sub-spectrum) divided in a frequency domain using a dispersed free band among a plurality of terminal stations. At
The terminal station calculates the number of initial modulation slots expressed in units of modulation slots of a fixed bandwidth corresponding to the half bandwidth of the modulation signal transmitted by the terminal station, and further calculates the number of initial modulation slots according to a plurality of band compression ratios. A compression modulation slot number calculating step of calculating the number of compressed modulation modulation slots,
A compression division pattern generation step of calculating a plurality of types of compression division patterns each of which is a combination of sub-spectrum obtained by dividing the number of compression modulation slots , for each of the plurality of band compression ratios;
From all the compression division patterns obtained by a plurality of types for each of the plurality of band compression ratios, among the compression division patterns that can be arranged in the free band, compression in which the peak power does not exceed the maximum transmission power of the terminal station. Select one compression division pattern with the minimum number of divisions from among the division patterns, or select a compression division pattern whose peak power does not exceed the maximum transmission power of the terminal station from among the compression division patterns with the minimum number of divisions A compression division pattern selection step of selecting one ;
A line allocation step of allocating a communication line to the terminal station based on the compression division pattern selected by the compression division pattern selection step and the distribution of the available bandwidth.

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