JP4425709B2 - Wireless communication control apparatus and method - Google Patents

Description

  The present invention relates to a wireless communication control apparatus and method for performing bidirectional communication.

  The two-way communication method includes a full-duplex communication method in which transmission and reception are performed using different frequencies, and a so-called half-duplex communication method in which transmission and reception are performed in a time division manner at the same frequency. It has been known. The full-duplex communication system is called an FDD (Frequency Division Duplex) system, and the half-duplex communication system is called a TDD (Time Division Duplex) system.

  By the way, the third generation mobile communication system IMT-2000 includes CDMA (Code Division Multiple Access) / FDD using different frequency bands in the uplink and CDMA / TDD using the same frequency band in the uplink and downlink. There is.

  As shown in FIG. 8A, the CDMA / FDD system requires a pair band because different frequency bands are used for uplink and downlink communications. In addition, this system has the advantage that the base station operates on an independent time base and synchronization between base stations is unnecessary.

  On the other hand, as shown in FIG. 8B, the CDMA / TDD scheme does not require an upstream / downward pair band, and therefore, when there is a difference in uplink / downlink traffic, the ratio of uplink / downlink time slots (time slots). It can be dealt with flexibly by changing. However, there is a feature that radio waves from a GPS (Global Positioning System) satellite are used for synchronization.

  Currently, commercialized third-generation mobile communication systems employ the CDMA / FDD system. However, the system mainly uses telephones (voice communication) with almost equal call volumes (traffic) for transmission and reception. ) Is designed on the assumption of traffic.

On the other hand, due to the rapid spread of the Internet, digitization of broadcasting, and the fusion of these media, the need for content with a large amount of downstream data such as music, images, and videos, that is, the need for asymmetric traffic, has become remarkable. The CDMA / TDD system can flexibly meet such traffic demands. For example, Patent Document 1 describes that the frequency utilization efficiency can be improved by dynamically changing the ratio of the uplink slot interval to the downlink slot interval in accordance with the uplink / downlink data amount.
JP-A-8-186533

  As described above, the conventional mobile communication system to which the FDD scheme is applied is designed on the assumption that the uplink and downlink traffic amounts are equal. However, in a mobile communication system intended to connect to the Internet, traffic has asymmetric and burst characteristics, so that there is a large difference in traffic volume between the two directions (uplink and downlink). That is, in the conventional mobile communication system to which the FDD scheme is applied, there is a problem that a line (frequency) is wasted when fluctuation occurs in uplink and downlink traffic.

  Hereinafter, this point will be described with reference to FIG. This figure is a conceptual diagram for explaining a conventional FDD system. The radio terminal 11 transmits a radio signal at the frequency f1 (uplink) and receives a signal at the frequency f2. The radio base station 12 transmits a radio signal at the frequency f2 (downlink) and receives a radio signal at the frequency f1. Here, transmission and reception on the uplink and downlink lines are performed independently at the same time. That is, in the conventional FDD scheme, the uplink and downlink capacities are the same, and the uplink is wasted if the capacity is matched to the downlink traffic volume.

  Further, when it is necessary to increase the bandwidth, there is a problem that it is difficult to secure a pair band particularly from the viewpoint of radio wave resources.

  On the other hand, the TDD scheme can use the frequency efficiently by adaptively changing the allocation of time slots allocated to the uplink and downlink according to the short-term traffic volume of the uplink and downlink using the same frequency band. Has a merit. However, when considering application to a cellular system with a multi-cell configuration, uplink transmission slots and downlinks are used to avoid interference between a plurality of mobile stations that exist in the vicinity and connect radio links to different cell sites. It is necessary to prevent the transmission slots from overlapping each other. That is, in order to apply the TDD scheme to the cellular system, time synchronization between cell sites (base stations) by using GPS or the like is essential. This has a problem in that it is disadvantageous in terms of cost with respect to flexible cell deployment, particularly indoors, for example, in places where GPS radio waves do not reach.

  The present invention has been made in view of the above problems, and the problem is that a difference occurs in the traffic volume of the uplink and downlink, and a pair band corresponding to the traffic volume ratio cannot be secured. Even so, it is to provide a radio communication control apparatus and method capable of effectively using a line (frequency).

This wireless communication control device
A wireless communication control device that performs bidirectional communication in both directions,
A first traffic fluctuation detection unit for detecting traffic fluctuations of a long-term uplink / downlink;
A second traffic fluctuation detection unit for detecting a short-term uplink / downlink traffic fluctuation;
A communication control unit that assigns uplink and downlink time slots to the first frequency band and assigns downlink slots to the second frequency band ;
Have
The communication control unit controls bandwidth allocation of the first and second frequency bands based on long-term uplink / downlink traffic fluctuations detected by the first traffic fluctuation detection unit, and The number of uplink / downlink time slots allocated to the first frequency band is controlled based on the short-term uplink / downlink traffic fluctuation detected by the second traffic fluctuation detector.

According to the wireless communication control device ,
The wireless communication control device,
The first traffic fluctuation detection unit detects the number of call request signals for a long time,
The second traffic fluctuation detecting unit detects the number of call request signals in a short time.

According to the wireless communication control device ,
The wireless communication control device,
The first traffic fluctuation detection unit detects a long-term downlink data amount,
The second traffic fluctuation detection unit detects a short-term downlink data amount.

According to the wireless communication control device ,
The wireless communication control device,
If the allocation ratio of time slots of the upper and lower link is controlled by the pre-Symbol communication control unit, the synchronization transmits a synchronization request signal using the second frequency band request signal transmitting unit
Is provided.

  According to the present invention as described above, there is a difference in the traffic volume between the uplink and the downlink, and the line (frequency) can be used efficiently even when the pair band cannot be secured.

  According to the present invention, it is possible to effectively use a line (frequency) even when there is a difference in traffic volume between the uplink and downlink, and a pair band corresponding to the traffic volume ratio cannot be secured. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a conceptual diagram for explaining a radio communication control method according to the present invention. In the figure, a wireless terminal (eg, mobile station) 21 performs transmission and reception with a wireless communication control device (hereinafter referred to as a wireless base station) 22 in a time division manner using a frequency f1.

  FIG. 2 is a diagram illustrating the concept of the TDD scheme. In the figure, TX represents transmission of the wireless terminal 21, and RX represents reception. In the radio base station 22, TX becomes a reception signal and RX becomes a transmission signal. As described above, the wireless terminal 21 and the wireless base station 22 perform the simultaneous transmission and reception by alternately switching the same frequency (in this example, f1) with time.

  As shown in FIG. 3, the wireless communication control method according to the present invention uses the frequency of f1 (bandwidth = W1) for both uplink and downlink communications by applying TDD, and the frequency of f2 (bandwidth = W2). Is characterized in that it is used exclusively for the downlink. That is to say, the conventional double-duplex uplink system has a half-duplex signal, thereby increasing the downlink communication capacity. As a result, it is possible to cope with a downlink with a large amount of traffic, and the entire system can be used effectively.

  Also, it is possible to flexibly cope with a change in traffic volume by changing the time ratio applied to transmission and reception according to the difference in traffic volume between the upper and lower lines.

  FIG. 4 is a functional block diagram showing a configuration example of a radio base station to which the radio communication control method according to the embodiment of the present invention is applied.

  In the figure, this radio base station 100 includes an antenna 101, a duplexer 102, a call request signal number short interval averaging unit 103, a long interval averaging unit A104, an up / down link bandwidth control unit 105, Link slot allocation number control unit 106, bandwidth / slot number notification signal generation unit 107, multiplexing unit 108, data amount monitoring unit 109, long interval averaging unit B110, downlink data buffer 111, downlink The transmission signal generating unit 112 is configured to perform wireless communication with a plurality of wireless terminals 210 to 230 in the service area (wireless zone).

  Next, the operation of radio base station 100 configured as described above will be described.

  A call request signal transmitted from each of the wireless terminals 210 to 230 is received by the antenna 101 and input to the call request signal number short interval averaging unit 103 and the uplink signal demodulating unit via the duplexer 102.

  The number of call request signals The short interval averaging unit 103 has a function of grasping rapid fluctuations in uplink traffic. Specifically, the number of call request signals transmitted from each of the radio terminals 210 to 230 is counted. By observing for about several hours from 100 ms and calculating the average value of the number of call request signals in the observed section (short section), it is possible to grasp a rapid fluctuation in uplink traffic.

  The long interval averaging unit A104 has a function of grasping gradual traffic fluctuation. Specifically, the short interval average value of the number of call request signals output from the short interval averaging unit 103 is the call request signal number. Is input and averaged over a long interval in the range of several tens of seconds (seconds) to several days.

  As described above, the call request signal number short interval averaging unit 103 and the long interval averaging unit A104 calculate the short interval average value and the long interval average value of traffic in the uplink. On the other hand, the data amount monitoring unit 109 and the long interval averaging unit B110 calculate the short interval average value and the long interval average value of the data amount in the downlink, respectively.

  The data amount monitoring unit 109 has a function of receiving the amount of downlink data stored in the downlink data buffer 111 as input, and grasping sudden fluctuations in downlink traffic. The amount of downlink data stored in the link data buffer 111 is observed for several hundreds of milliseconds to several hours, and the average value of the downlink data amount in the observed section (short section) is calculated, so that the abrupt downlink Understand fluctuations in traffic. The downlink data buffer 111 is a buffer (memory) that accumulates downlink data transmitted from the network side.

  The long interval averaging unit B110 has a function of grasping moderate fluctuations in downlink traffic. Specifically, the long interval averaging unit B110 receives a short interval average value of the downlink data amount output from the data amount monitoring unit 109 as an input. , Averaging over a long interval in the range of several tens of seconds (seconds) to several days.

  Here, an example of a sudden change in traffic and an example of a gentle change in traffic will be described.

  As an example of sudden traffic fluctuations, a wide range of types of communication is performed with multimediaization. For example, when a user receives a video streaming service, there is a time when there is downlink traffic. It suddenly increases (changes) at the border.

  In addition, the transmission size of electronic mail increases dramatically when the user transmits digital photos, videos, and the like. That is, it increases (fluctuates) abruptly when there is uplink traffic.

  That is, it is considered that the upper and lower traffic amounts fluctuate rapidly depending on the type of service, and that the upstream and downstream traffic is biased for each communication.

  On the other hand, as an example of the gradual change in traffic, an example is a change in the type of radio terminal in the service area formed by the radio base station. For example, in a service area in an office area, business people are often used during the day, and there is a lot of downlink traffic such as data downloads. Thus, the difference in traffic volume between the upper and lower links is reduced.

  That is, it is considered that the upper and lower traffic amounts vary gradually from time to time, and the upstream and downstream traffic is biased.

Returning to FIG. 4, the description will be continued. The uplink / downlink bandwidth control unit 105 performs bandwidths W1 and W2 (based on the uplink traffic length interval average value and the downlink traffic length interval average value output from the long interval averaging unit A104 and the long interval averaging unit B110 ( (See FIG. 3). For example, control is performed to change the distribution of the bandwidths W1 and W2.
Based on the short interval average values output from the call request signal number short interval averaging unit 103 and the data amount monitoring unit 109, the uplink / downlink slot allocation number control unit 106 determines the uplink slot allocation number (Nu) in W1. Controls the number of downlink slot allocation (Nd). For example, control is performed to change the allocation of uplink and downlink slots.

  Hereinafter, the operations performed by the uplink / downlink bandwidth control unit 105 and the uplink / downlink slot allocation number control unit 106 will be described with reference to FIG. It is assumed that time elapses in the descending order of FIGS. 5 (a) to 5 (d) and the traffic on the upper and lower links is fluctuating, and the description will proceed.

  FIG. 5A shows a case where the average traffic amount in the short and long sections of the upper and lower links is constant. In this case, the uplink / downlink bandwidth control unit 105 performs the uplink long interval average traffic amount 5 averaged by the long interval averaging unit A104 and the downlink long interval average traffic averaged by the long interval averaging unit B110. The amount 15 is input, and the bandwidths W1 and W2 are controlled based on the input long-term average traffic amounts. Here, it is assumed that W1 = 10 and W2 = 10.

  The bandwidths W1 and W2 controlled by the uplink / downlink bandwidth control unit 105 in this way are notified to the uplink / downlink slot allocation number control unit 106. The uplink / slot slot allocation number control unit 106 has an uplink short interval average traffic amount 5 averaged by the call request signal number short interval averaging unit 103 and a downlink short interval averaged by the data amount monitoring unit 109. With the average traffic volume 15 as an input, control is performed to determine the number of uplink / downlink slot assignments within the notified W1. For example, in the case of this example, since the downlink short section average traffic amount = 15, out of the downlink short section average traffic amount 15, the traffic amount 10 is transmitted from the frequency of the downlink dedicated f2 having the bandwidth W2. Is done. Then, the uplink / slot slot allocation number control unit 106 allocates slots for the remaining downlink short interval average traffic volume 5 and uplink short interval average traffic volume 5 within W1. Specifically, 5 may be assigned as the number of slots of the downlink short interval average traffic volume 5 (Nd = 5), and 5 may be allocated as the number of slots of the uplink short interval average traffic volume 5 (Nu = 5).

  Subsequently, the example of FIG. 5B will be described. In FIG. 5 (b), the downlink short section average traffic volume is decreased (15 → 11) compared to FIG. 5 (a), and conversely the uplink short section average traffic volume is increased (5 → 9). Shows the case.

  When such traffic fluctuation occurs, out of the downlink short-term average traffic volume = 15, the traffic volume 10 is derived from the frequency of the downlink dedicated f2 having the bandwidth W2 as in the case of FIG. 5 (a). Sent.

  Then, the uplink / downlink slot allocation number control unit 106 allocates slots for the remaining downlink short interval average traffic amount 1 and uplink short interval average traffic amount 9 within W1. Specifically, 1 may be assigned as the number of slots of the downlink short interval average traffic amount 1 (Nd = 1), and 9 may be allocated as the number of slots of the uplink short interval average traffic amount 9 (Nu = 9).

  Next, the example of FIG. 5C will be described. In FIG. 5 (c), the downlink short interval average traffic volume and the uplink short interval average traffic volume are not changed as compared with FIG. 5 (b), and the downlink long interval average traffic volume decreases (15 → 11), and the uplink long-section average traffic amount is increasing (5 → 9), that is, the case where the traffic on the uplink and downlink is slowly changing.

  In such a case, the uplink / downlink bandwidth control unit 106 is notified by the long interval averaging unit B110 that the downlink long interval average traffic amount is decreasing, so that the downlink dedicated bandwidth W2 is narrowed (this In the example, W2 = 10 → 2). On the other hand, since it is notified from the long section averaging unit A104 that the uplink long section average traffic amount is increasing, W1 is controlled to be widened (in this example, W1 = 10 → 18). In this example, as an example, it is assumed that the traffic amount 2 out of the downlink short interval average traffic amount = 11 is transmitted from the downlink dedicated frequency f2 having the bandwidth W2.

  The uplink / downlink slot allocation number control unit 106 allocates slots for the remaining downlink short interval average traffic volume 9 and uplink short interval average traffic volume 9 within W1. Specifically, 9 may be assigned as the number of slots of the downlink short interval average traffic volume 9 (Nd = 9), and 9 may be allocated as the number of slots of the uplink short interval average traffic volume 9 (Nu = 9).

  Next, the example of FIG. 5D will be described. In FIG. 5 (d), the downlink short interval average traffic volume has increased (11 → 14) compared to FIG. 5 (c), and the uplink short interval average traffic volume has decreased (9 → 6). Is shown.

  In such a case, since the downlink long interval average traffic amount and the uplink long interval average traffic amount do not vary as compared with FIG. 5 (c), the uplink / downlink bandwidth control unit 106 performs the processing shown in FIG. 5 (c). The bandwidth of W1 and W2 set at the time of is not changed. In this example, in such a case, the uplink / downlink slot allocation number control unit 106 changes only the slot ratio of the uplink and downlink. Specifically, since the downlink short section average traffic amount has increased from 11 to 14, the number of downlink slots is changed from 9 to 12. On the other hand, since the uplink short section average traffic amount has decreased from 9 to 6, the number of uplink slots may be changed from 9 to 6.

  W1 and W2 controlled by the uplink / downlink bandwidth control unit 105 as described above, and Nu and Nd controlled by the uplink / downlink slot allocation number control unit 106 are the bandwidth / slot number notification signal generation unit 107 as control information. Is input. The bandwidth / slot number notification signal generation unit 107 generates a notification signal for notifying the wireless terminal of the input control information of W1, W2, Nu, and Nd, and outputs the notification signal to the multiplexing unit. Also, the bandwidth / slot number notification signal generation unit 107 generates and transmits a synchronization request signal for synchronizing between transmission and reception when notifying the control information of Nu and Nd as a notification signal. The synchronization request signal may be notified using the frequency f2, for example.

  The multiplexing unit 108 multiplexes the notification signal and the downlink transmission signal output from the downlink transmission signal generation unit 112. Then, the signal multiplexed by the multiplexing unit 108 is transmitted to the antenna 101 via the duplexer 102 and transmitted to each of the wireless terminals 210 to 230.

  As described above, according to the present embodiment, for example, the downlink dedicated f2 frequency band (= W2) alone is insufficient for accommodating downlink traffic and is sufficient for accommodating uplink traffic. Even if the frequency band (= W1) of f1 is unnecessarily large, it is possible to accommodate the downlink traffic using both f1 and f2, thereby avoiding waste of the line (frequency). Traffic can be accommodated with high efficiency. Therefore, even when the W1 and W2 pair bands corresponding to the uplink and downlink traffic volumes cannot be secured, effective use of the frequency can be realized.

  Further, in this embodiment, when the traffic volume of the uplink and the downlink gently changes, the frequency bandwidth W1 of f1 and the frequency bandwidth W2 of f2 are changed according to the gentle change. For example, when uplink traffic increases with time and the downlink traffic volume decreases, W2 is decreased and W1 is increased. Conversely, when downlink traffic increases and uplink traffic volume decreases, W2 is increased and W1 is decreased. By controlling the bandwidths of W1 and W2 in this way, it becomes possible to accommodate uplink and downlink traffic with high efficiency without increasing the bandwidth of the entire system.

  Next, a hardware configuration example of the above-described radio base station will be described with reference to FIG. The radio base station in the present embodiment has a function of performing radio communication with a radio terminal using the TDD scheme using the frequency f1 and the FDD scheme using the frequency f2.

  In the figure, the signal of the frequency f1 received by the antenna 41 is output from one of the terminals of the antenna sharing circuit (DUP) 42, input to the receiving circuit 45 via the circulator 44, and demodulated. After receiving signal processing, the signal is output to the reception output terminal 47. Transmission signals input from the input terminals 461 and 462 are subjected to transmission signal processing such as modulation by transmission circuits (TX1) 431 and (TX2) 432, respectively. The frequencies of the output signals of the transmission circuits 431 and 432 are f2 and f1, respectively. The output signal of the transmission circuit 431 is input from one terminal of the antenna sharing circuit 42 and transmitted from the antenna 41.

  The output signal of the transmission circuit 432 passes through the circulator 44, is input from the other terminal of the antenna sharing circuit 42, and is transmitted from the antenna 41. The operation of the circulator 44 is such that a signal input from a certain terminal is output only from an adjacent terminal in the direction of the arrow. The antenna sharing circuit 42 performs an operation of separating or synthesizing signals having different frequencies. Since these operations are well known, further detailed description is omitted.

  Next, a hardware configuration example of a wireless terminal that performs wireless communication with the above-described wireless base station will be described with reference to FIG. The wireless terminal in the present embodiment has a function of performing wireless communication with a wireless base station using the TDD method using the frequency f1 and the FDD method using the frequency f2.

  In the figure, the signal of the frequency f2 received by the antenna 51 is output from one terminal of the antenna sharing circuit 52, and after receiving signal processing in the receiving circuit 531, it is output to the output terminal 561. Similarly, the reception signal of frequency f1 is output from the other output terminal of the antenna sharing circuit 52, passes through the circulator 54, is input to the reception circuit 532, is subjected to reception signal processing, and is output to the output terminal 562. The

  The transmission signal input to the input terminal 57 is subjected to transmission signal processing by the transmission circuit 55 and becomes a signal of frequency f1. The output of the transmission circuit 55 passes through the circulator 54 and is then input to the antenna sharing circuit 52 and transmitted from the antenna 51.

  In the above embodiment, the case where the wireless base station and the wireless terminal perform wireless communication using a single carrier is exemplified as one aspect, but the present invention is not limited to such an aspect, and the wireless base station and the wireless terminal are wirelessly connected by a multicarrier. The present invention can be applied even when communication is performed.

  In the above embodiment, the functions of the short request averaging unit 103, the long reference averaging unit A104, the data amount monitoring unit 109, and the long reference averaging unit B110 of the radio base station 100 are used as the traffic amount measuring means. The functions of the uplink / downlink bandwidth control unit 105 and the uplink / downlink slot allocation number control unit 106 correspond to control means. The functions of the radio base station shown in FIG. 6 correspond to time division communication means and frequency division communication means. In addition, the functions of the call request signal short interval averaging unit 103 and the data amount monitoring unit 109 are used as a sudden change detecting unit, the function of the uplink / downlink bandwidth control unit 105 is used as the bandwidth control unit, and the long interval averaging unit A104. The function of the long interval averaging unit B110 is a slow fluctuation detection unit, the function of the uplink / downlink slot allocation number control unit 106 is a slot control unit, and the function of the bandwidth / slot number notification signal generation unit 107 is a synchronization request signal transmission unit. Corresponding to

It is a conceptual diagram for demonstrating the radio | wireless communication control method which concerns on embodiment of this invention. It is a figure which shows the concept of a TDD system. It is a figure which shows the structural example of this invention. It is a functional block diagram which shows the structural example of the radio base station to which the radio | wireless communication control method which concerns on embodiment of this invention is applied. It is a figure for demonstrating operation | movement of the radio | wireless communication control method which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the wireless base station which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the radio | wireless terminal which concerns on embodiment of this invention. It is a figure which shows the example of a structure of a full duplex duplicate system and a half duplex duplicate system. It is a conceptual diagram for demonstrating the conventional full-duplex communication system.

Explanation of symbols

11, 21, 210-230 Radio terminal 12, 22, 100 Radio base station 41, 51 Antenna 42, 52 Shared antenna circuit 45, 531, 532 Receiver circuit 44, 54 Circulator 461, 462, 57 Transmit signal input terminal 47, 561 , 562 Received signal output terminal 101 Antenna 102 Duplexer 103 Number of outgoing call request signals Short interval averaging unit 104 Long interval averaging unit A
105 Up / Down Link Bandwidth Control Unit 106 Up / Down Link Slot Allocation Number Control Unit 107 Bandwidth / Slot Number Notification Signal Generation Unit 108 Multiplexing Unit 109 Data Amount Monitoring Unit 110 Long Section Averaging Unit B
111 Downlink data buffer 112 Downlink transmission signal generator

Claims (5)

A wireless communication control device that performs bidirectional communication in both directions,
A first traffic fluctuation detection unit for detecting traffic fluctuations of a long-term uplink / downlink;
A second traffic fluctuation detection unit for detecting a short-term uplink / downlink traffic fluctuation;
A communication control unit that assigns uplink and downlink time slots to the first frequency band and assigns downlink slots to the second frequency band ;
Have
The communication control unit controls bandwidth allocation of the first and second frequency bands based on long-term uplink / downlink traffic fluctuations detected by the first traffic fluctuation detection unit, and Radio communication control characterized by controlling the number of uplink / downlink time slots allocated to the first frequency band based on short-term uplink / downlink traffic fluctuations detected by two traffic fluctuation detectors apparatus. The wireless communication control device according to claim 1,
The first traffic fluctuation detection unit detects the number of call request signals for a long time,
Said second traffic change detection unit, a radio communication control device according to claim that you detect a call request signal number of short time. The wireless communication control device according to claim 1 or 2 ,
The first traffic fluctuation detection unit detects a long-term downlink data amount,
Said second traffic change detection unit, a radio communication control device according to claim that you detect the data amount of short downlink. The wireless communication control device according to claim 1 ,
If the allocation ratio of time slots of the upper and lower link is controlled by the pre-Symbol communication control unit, a radio communication, characterized in that it comprises a synchronization request signal transmission unit for transmitting a synchronization request signal using the second frequency band Control device. A radio communication control method in a wireless communication control apparatus for communicating in a vertical link bidirectionally,
A first traffic fluctuation detection step for detecting long-term traffic fluctuation of the uplink and downlink;
A second traffic fluctuation detection step for detecting a short-term uplink / downlink traffic fluctuation;
A communication control step of allocating uplink and downlink time slots to the first frequency band and allocating downlink slots to the second frequency band;
Have
In the communication control step, bandwidth distribution of the first and second frequency bands is controlled based on the long-term uplink / downlink traffic variation detected by the first traffic variation detection step, and the first Radio communication control characterized in that the number of uplink / downlink time slots allocated to the first frequency band is controlled based on the short-term uplink / downlink traffic fluctuation detected by the traffic fluctuation detection step (2). Method.

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