JP5378268B2 - Radio base station, radio communication system, and radio base station traffic level determination method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid congestion by accurately predicting traffic occurring in a radio section. <P>SOLUTION: Terminal stations under a radio base station itself are classified into a first group, namely a group of existing terminal stations in the service zone of the radio base station, and a second group, namely a group of non-existing terminal stations in the service zone of the radio base station. Each of the amount of traffic generated by a terminal station belonging to the first group and the amount of traffic generated by a terminal station belonging to the second group, is predicted. A value which is obtained by subjecting the predicted amount of traffic to weighted mean, is calculated as the next traffic. When the calculated next traffic is not less than a prescribed upper limit, a traffic level is changed from a present-state value to a traffic level, where transmission regulations of the terminal station are strengthened. When the next traffic is not larger than a prescribed lower limit, the traffic level is changed from the present-state value to a traffic level, where the transmission regulations of the terminal station are weakened. An updated traffic level is transmitted to each terminal station. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a radio base station, a radio communication system, and a traffic level determination method for a radio base station in a wireless sensor network in which a large number of terminal stations exist in a communication area and transmit and receive a small amount of data at sparse intervals.

  Data transmitted in the wireless network is transmitted to the receiving side at sparse intervals. Examples of the data to be transmitted include sensing data transmitted at a frequency of about once a month, sudden sensing transmitted when a disaster occurs, and the like. Further, this data is a numerical value of the sensor, ON / OFF information, etc., and one data size is small.

  From now on, it is assumed that the present invention is applied not only to communication while receiving instructions from the user, but also to all things. Here, there is a terminal device that has several years of battery driving in order to expand the application range. In such a terminal device, it is desirable not to perform unnecessary data transmission and standby.

  Incidentally, there is a mobile phone as an example of a terminal device. In this mobile phone, call control is performed in the transport layer. A scene using this cellular phone is a case where broadband wireless communication is performed, and large-capacity data transmission is assumed. As congestion control in this case, for example, there is TCP Vegas that is typical in TCP congestion control. The RTT (round trip time) is measured at End-End, the congestion degree is determined, and the window size when transmitting is changed. Things have been done. Furthermore, by using the slow start method, at the start of a certain data transmission open session, transmission is started with a small window size, and congestion is avoided by changing the window size while monitoring the mix of routes according to the RTT. I am trying (see Non-Patent Document 1).

On the other hand, multi-hop sensor networks are also being used. In the case of a wireless sensor network, a network that multi-hops short-range radio such as ZigBee is being studied.
Regarding the congestion control of the wireless link of such a network, there is Non-Patent Document 2 shown below. In this non-patent document 2, first, a mechanism called Hop-by-hop flow control is used to transmit the empty state of its own transmission queue in the header information as a congestion bit. That is, each node of the network Inform yourself of the degree of congestion.
Next, there is a method called Rate Limiting that monitors the information and monitors the surrounding situation. In this method, based on the monitored information, the size of the backoff at the time of CSMA is changed as an operation of the MAC layer. That is, each terminal station itself has proposed a method of autonomously changing the waiting time during transmission depending on the degree of congestion (see Non-Patent Document 2).

Senda et al., "Performance Evaluation of TCP Congestion Control Method in HSDPA", 2007 Annual Conference of the IEICE General Conference B-7-188 Reference 2: Bret Hull, Kyle Jamieson, Hari Balakrishnan, “Mitigating Congestion in Wireless Sensor Networks”, SenSys’04, November 3-5, 2004, Baltimore, Maryland, USA.

  However, in the network using the mobile phone described above, as a method for predicting the traffic in the radio section when managing the terminal station, “typical traffic per number of terminals under the control of the radio base station × one traffic” It is conceivable to predict the traffic volume under the radio base station using the “model”. However, in the case of a mobile phone, the terminal station always registers its location with the radio base station and always maintains a standby state. Thus, preparations are made so that incoming calls can be made anytime.

  However, when small data is transmitted only occasionally, such as sensor information, if the standby state is always maintained, the standby state is maintained even though the communication is not performed for a long period of time. It will be useless. On the other hand, if the standby state is not performed in order to reduce power consumption, there are terminals that do not transmit data at a desired timing, that is, whether the wireless base station exists in its own communication area on demand. It is difficult to make a determination, and a terminal station management method based on this is required.

  Next, in the case of grasping the degree of congestion in the wireless section, when transmitting sensor information or the like, the amount of data is mainly small amount of data communication so as to fit into one packet, and then the data is transmitted. The period until this is after a big vacancy from this time. Therefore, in the method of trying RTT for data transmission, the overhead of control data increases with respect to the ratio of data to be transmitted, which is inefficient. Here, when trying to use RTT at the time of the previous data transmission, the degree of congestion is different because the degree of use of the wireless section is clearly changed between the previous transmission and the current transmission. There is a problem that the data is not reliable.

On the other hand, when managing terminal stations in a multi-hop sensor network, it is essential to grasp the entire network state in order to accurately grasp the network state. However, if the network is unstable due to multi-hop, or if it is non-patent document 2, the network itself is transmitted by Hop-by-hop flow control so that the terminal stations can communicate their own situation. For this reason, there is a problem that the overhead of control data increases with respect to the size of data such as sensor information.
Further, the power consumption for transmission for the terminal stations to communicate the situation themselves, and the power consumption for monitoring the signals for communicating the situation in an unstable network topology change are increased. In addition, since these terminal stations make an autonomous determination, it is necessary to provide a function in each terminal station, and there is a problem in that it becomes highly functional.

  The present invention has been made in view of such circumstances, and an object of the present invention is to accurately predict traffic generated in a radio section and avoid congestion, a radio base station, a radio communication system, and a radio base station. It is to provide a traffic level determination method.

In order to solve the above-described problem, the present invention provides a base station apparatus in a radio communication system in which a base station apparatus that communicates with a terminal station determines a value of a transmission permission probability of the terminal station according to a plurality of traffic levels. The first group which is a group of terminal stations whose access or presence has been confirmed within a predetermined time and the terminal stations whose access or presence has not been confirmed within a predetermined time. A group management unit for classifying the second group as a group;
A traffic amount prediction unit for predicting a traffic amount generated by a terminal station belonging to the first group and a traffic amount generated by a terminal station belonging to the second group;
A calculation unit for calculating a weighted average value of the obtained predicted traffic amount as next traffic;
When the calculated next traffic is greater than or equal to a predetermined upper limit, the traffic level is changed from the current value to a traffic level that tightens transmission restrictions of the terminal station, and the next traffic is less than or equal to a predetermined lower limit. A traffic level update unit that changes the level from a current value to a traffic level that weakens the transmission restriction of the terminal station, and a traffic level transmission unit that transmits the traffic level updated by the traffic level update unit to each terminal station, It is characterized by having.

Further, the present invention provides the above-described wireless communication station, a measuring unit for its own radio base station measures the traffic volume that communicates, the traffic volume prediction unit, the prediction traffic volume obtained by the prediction The next traffic amount is predicted based on the traffic amount measured by the measuring unit.

  Further, the present invention provides a setting information storage unit that stores setting information, which is information in which a traffic level and the transmission permission probability are associated with each other, and is updated by the traffic level update unit in the wireless communication station described above. A traffic level storage unit that stores the traffic level, a transmission unit that transmits data to the terminal station, and a transmission that corresponds to the traffic level stored in the traffic level storage unit when transmitting data from the transmission unit A transmission determination unit that reads the permission probability and permits transmission from the transmission unit according to the read transmission permission probability.

  The present invention is also a wireless communication system in which a base station apparatus that communicates with the terminal station determines a value of a transmission permission probability of the terminal station according to a plurality of traffic levels, and the base station apparatus A first group which is a group of terminal stations whose access or location has been confirmed within a predetermined time and a second group of terminal stations whose access or location has not been confirmed within a predetermined time A group management unit that classifies the received data into a group, a traffic amount prediction unit that predicts a traffic amount generated by a terminal station belonging to the first group and a traffic amount generated by a terminal station belonging to the second group, respectively A calculation unit that calculates a weighted average of the obtained predicted traffic amounts as next traffic, and the calculated next traffic is equal to or greater than a predetermined upper limit value. If the traffic level is changed from the current value to a traffic level that tightens terminal station transmission restrictions, and the next traffic is below a predetermined lower limit, the traffic level is reduced from the current value to weaken the terminal station transmission restrictions. A traffic level update unit that changes to a traffic level transmission unit that transmits the traffic level updated by the traffic level update unit to each of the terminal stations, the terminal station including the traffic level and the transmission permission probability Is a setting information storage unit that stores setting information that is associated with each other, a traffic level storage unit that receives and stores a traffic level transmitted from the radio base station, and transmits data to the radio base station The terminal station transmitter, and when transmitting data from the terminal station transmitter, the traffic level Reads the transmission permission probability corresponding to the traffic level stored in 憶部, according to the read transmission permission probability, and having a transmission determination unit for permitting transmission from the terminal station transmitting unit.

  In addition, the present invention is a method for determining a traffic level of a radio base station in a radio communication system in which a base station apparatus that communicates with the terminal station determines a value of a transmission permission probability of the terminal station according to a plurality of traffic levels. Then, the group management unit of the radio base station accesses or visits within a predetermined time with a first group that is a group of terminal stations whose access or presence is confirmed within a predetermined time. Is classified into a second group that is a group of terminal stations for which the radio base station has not been confirmed, and the traffic volume prediction unit of the radio base station determines the traffic volume generated by the terminal stations belonging to the first group and the second group The amount of traffic generated by each terminal station belonging to the group is predicted, and the calculation unit of the radio base station calculates the weighted average value of the obtained predicted traffic amount next time. The traffic level update unit of the wireless base station changes the traffic level from the current value to a traffic level that strengthens the transmission restriction of the terminal station when the calculated next traffic is greater than or equal to a predetermined upper limit value. When the next traffic is below a predetermined lower limit value, the traffic level is changed from the current value to a traffic level that weakens the transmission restriction of the terminal station, and the traffic level transmitting unit of the radio base station updates the traffic level. The traffic level updated by the unit is transmitted to each terminal station.

As described above, according to the present invention, the first station, which is a group of terminal stations whose access or presence has been confirmed within a predetermined time, and the access or presence within a predetermined time have been confirmed. A second group, which is a group of non-terminal stations, and predicts a traffic volume generated by a terminal station belonging to the first group and a traffic volume generated by a terminal station belonging to the second group, respectively. The weighted average value of the traffic volume is calculated as the next traffic, and when the calculated next traffic is equal to or greater than a predetermined upper limit value, the traffic level is changed from the current value to a traffic level that strengthens the transmission restriction of the terminal station, Traffic level that weakens the terminal station's transmission restrictions from the current value when the next traffic is below the specified lower limit. Change, and to transmit to each terminal station. Thereby, communication regulation can be performed on the terminal station according to the traffic level.
Therefore, the traffic in the radio section can be controlled so that the communication is not congested, and the amount of information to be notified to the terminal station is discrete data called a traffic level. Can be reduced.
In addition, since the traffic level is determined based on the traffic volume of these groups divided into the first and second groups, more accurate traffic prediction according to the access status of the terminal station can be performed.

It is a schematic block diagram which shows the structure of the radio | wireless communications system by one Embodiment. 2 is a block diagram illustrating functions of a radio base station 20. FIG. It is a figure showing an example of traffic level setting information. It is a figure showing the case where the bit string which shows the propriety of transmission is provided in a part of ID of the terminal station. It is a block diagram showing the structure of a terminal station. 5 is a flowchart for explaining the operation of the radio base station 20.

Hereinafter, a wireless communication system according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram showing a configuration of a wireless communication system according to an embodiment of the present invention. In this figure, the radio base station 20 communicates with each terminal station (13, 14, 15, 16, 17, 18) in the communication area 10, which is an area in which the radio base station 20 can communicate.
The terminal stations 13, 14, 15, 16, 17 and 18 exist in the communication area 10 and have a function of communicating with the radio base station 20. Here, assuming a ubiquitous infrastructure covering a wide area as in Reference 3 (when the communication area is several kilometers), the number of terminal stations existing in the communication area ranges from several thousand to several tens of thousands. It is also possible. Here, a wireless communication system in which a plurality of the present wireless communication systems are integrated may be used.

  Wireless communication system for transmitting sensor information, etc. that is P-MP type in a communication area of several kilometers and accommodates a large number of terminal stations under the control of wireless base stations (Reference 3: Watanabe et al., “Wide-area ubiquitous network infrastructure Of wireless system for industrial use ”, 2006 IEICE General Conference B-5-148)

The terminal stations 13, 14, 15, and 16 access the radio base station 20 every certain period.
The terminal stations 17 and 18 do not access within a certain period of time, but exist in the communication area 10 and communicate with the radio base station 20 as necessary.

FIG. 2 is a block diagram illustrating functions of the radio base station 20.
In this figure, a radio base station 20 includes a radio transmission / reception unit 21, a traffic measurement unit 23, a traffic level conversion unit 24, a traffic level storage unit 25, a control signal generation unit 26, a transmission determination unit 27, a traffic level reference / change interface ( IF) 28 and a threshold value storage unit 29.

  The wireless transmission / reception unit 21 transmits / receives a wireless signal to / from each terminal device. The list management unit 22 includes a list A indicating that the wireless transmission / reception unit 21 communicates with the terminal station and a terminal station that has been accessed within a certain period of time, and a terminal station that has not accessed within the certain period of time. It is determined for each terminal station whether it corresponds to the list B indicating that it is, and according to the determined result, it is assigned to the list A or the list B for each terminal station. Here, there are a method of determining a list based on whether there is an access from the terminal station side and a method of determining a list by polling. The polling method is a method of actively confirming the location of the terminal station from the radio base station 20 at a predetermined interval. Polling is performed from the radio base station side to perform alive monitoring. For example, if the location is confirmed by polling within a certain time (for example, within 2 hours), it is determined as list A, and if it is not confirmed within a certain time, it is determined as list B. In addition, the list management unit 22 stores the determination result in a memory area that the list management unit 22 has.

  The traffic measurement unit 23 measures the traffic volume of the radio signal (uplink) received from each terminal station and the radio signal (downlink) to be transmitted to each terminal station as the traffic volume per unit time. The traffic measurement unit 23 measures the uplink traffic amount by measuring the uplink radio signal received by the radio transmission / reception unit 21, and measures the downlink traffic amount by measuring the downlink radio signal that has passed through the transmission determination unit 27. Measure.

  The traffic level conversion unit 24 manages the traffic level. More specifically, the traffic level conversion unit 24 converts the measured traffic amount per unit time into a traffic level value, the traffic amount measured by the traffic measurement unit 23, and a predetermined reference value. And a function of determining whether or not to change the current traffic level based on the comparison result. The traffic level storage unit 25 stores the traffic level value converted by the traffic level conversion unit 24. Here, the uplink traffic level and the downlink traffic level at the time of measurement are stored.

Here, the determination of the traffic level conversion unit 24 will be described. The traffic level conversion unit 24 compares the traffic amount measured by the traffic measurement unit 23 with a predetermined reference value, and changes the value of the traffic level stored in the traffic level storage unit 25 based on the comparison result. It is determined whether or not to do.
That is, it is conceivable to store in advance as a predicted traffic amount with respect to the allowable traffic amount of the system as a threshold value. For example, when the predicted traffic volume exceeds the upper reference value, which is 70% (Xupper) of the allowable traffic volume of the system, the traffic level to apply another level of regulation to the currently set traffic level To make a change to In the present embodiment, on the contrary, when the lower limit reference value, which is 30% (Xlower) of the allowable traffic amount, is exceeded, a determination is made that the traffic level is set to relax the regulation one step below the current traffic level. I do.

FIG. 3 is a diagram illustrating an example of traffic level setting information. In this figure, there are traffic levels from 0 to 7, and a transmission percentage value is associated with each of these levels, thereby defining a transmission permission / rejection percentage for each traffic level.
This traffic level setting information is shared by the radio base station 20 and all the terminal stations, and is used for determining whether or not transmission is possible for a transmission request. For example, if the current traffic level at the radio base station 20 is “3”, transmission for a transmission request is permitted with a probability of 62.5%, which is a transmission percentage associated with this traffic level “3”. Become. At that time, if the predicted traffic exceeds 70% (Xupper), which is the threshold value of the allowable traffic amount, the traffic level is raised in the direction of regulating, and the traffic level is changed to “4” and held.

The traffic level is a value obtained by multiplying the value of the predicted traffic related to the terminal station whose access to the radio base station 20 is confirmed within a certain time by a constant α defined in the past. And the value obtained by multiplying the value of the predicted traffic related to the terminal station for which access has not been confirmed by the constant β specified, and dividing the added value by the sum of α and β. Conversion may be performed from the traffic amount per unit time of the radio base station.
That is, a list of terminal stations whose access to the radio base station has been confirmed within a predetermined time is set as list A, and traffic is predicted from the terminal station attribute information and the like for the terminal stations described in list A. Further, a list of terminal stations that have been accessed in the past but have not been confirmed to be accessed within a certain period of time is referred to as list B, and the traffic is similarly predicted.

  For example, if the list A has 10,000 terminal stations with a 100-byte data model once a week and 200 terminal stations with a 10-byte data model once an hour, the prediction is as follows. The predicted traffic level is calculated based on the amount of data, its frequency, and the number. In addition, if List B has 2000 terminal stations with a 100-byte data model once a week and 1200 terminal stations with a 10-byte data model once an hour, the predicted traffic level of List S Is calculated based on the amount of data, its frequency, and the number of units. Here, in both lists A and B, the generated traffic per unit time of each list may be calculated, including a control signal and the like, which is an overhead during data communication.

In a wireless system in which communication is performed at sparse intervals and location registration is not performed at all times, it is difficult to determine an active terminal station due to movement of the terminal station or the like. Therefore, in this embodiment, the presence / absence of access within a certain period of time is used as a judgment material, the presence status of the terminal station is predicted, and the predicted traffic of the terminal station corresponding to the list A that is more likely to be in the area is calculated. The prediction accuracy of the next traffic is increased by predicting the traffic with a higher weight.
Based on the next traffic (Lt), conversion to traffic level is performed. The formula at this time is shown in the following formula (1).

  In the next traffic prediction, as shown in the following equation (2), the value θ representing the amount of the latest actual traffic measured by the radio base station 20 is used as a new weight with respect to the equation (1). The traffic level may be predicted in accordance with the following equation (2), which is an equation considered in the above.

The transmission determination unit 27 performs transmission determination on the downlink radio signal. That is, in response to a transmission request to the terminal station, the transmission determination unit 27 refers to the traffic level storage unit 25 in which the traffic level setting information currently held by the radio base station 20 is stored, and performs the above-described traffic level determination. .
If the traffic level setting information of FIG. 3 is read and the current traffic level is “3”, the transmission determination unit 27 permits transmission with a probability of 62.5%. When it is determined that transmission is permitted, the transmission determination unit 27 transmits a signal to the terminal station via the wireless transmission / reception unit 21. When it is determined that transmission is not permitted, the transmission determination unit 27 indicates that transmission is not possible from the transmission determination unit 27 to the transmission request source. Send back.

  The traffic level reference / change IF 28 indicates an interface for directly changing a traffic level setting information stored in the traffic level storage unit 25 by a previously authorized user such as a system administrator. The traffic level reference / change IF 28 not only allows the traffic level to be mechanically autonomously changed, but also allows the traffic level to be directly changed artificially according to the surrounding situation.

  The traffic volume per unit time to be used and the traffic level used here may be managed separately for the uplink radio signal and the downlink radio signal, and used for each transmission request. Further, the traffic volume per unit time to be measured may be the traffic volume of the transmission request or the transmitted actual traffic volume.

FIG. 4 is a diagram illustrating a case where a bit string indicating whether transmission is possible is provided as part of the ID of the terminal station as an example of traffic level setting information. In the example of this figure, when the ID of the terminal station is assigned as a decimal integer, the traffic level is represented as a string of bits indicating whether or not transmission is possible for the last digit.
For example, if the traffic level is 16 steps, it can be represented by 4 bits, but instead use 10 bits, and if it is “1”, transmission is possible if it is assumed to be the last digit of the terminal station ID. If “0”, transmission may be disabled.
In this way, information indicating whether or not transmission is possible is provided for the bit corresponding to the number of the last one digit of the terminal station ID, and by transmitting this information to the terminal station, the terminal station receiving this information Referring to the bit corresponding to the last digit of the ID of the terminal station, it is possible to determine whether or not the own station can transmit and control transmission. For example, if the last digit of the terminal station ID is “5”, the value of the sixth bit is referred to. Here, since it is “1” and represents that transmission is possible, the local station determines that transmission is possible and transmits data to the radio base station 20. In this case, it is possible to perform control in consideration of the terminal station group, as compared with the case where the terminal station determines the probabilistic transmission availability shown in FIG. In order to make the group granularity fine, the bit string may be enlarged so that the bit string can represent the number of groups.

  In the traffic level setting information stored in the traffic level storage unit 25, a value representing a level corresponding to the traffic volume is read by the control signal generation unit 26 and incorporated in the control signal of the wireless communication system. It is transmitted by the broadcast control signal at the notification timing.

  FIG. 5 is a block diagram showing the configuration of the terminal station. In this figure, the terminal station 13 is described as an example, but this configuration also includes other terminal stations (14 to 18). The radio transmission / reception unit 132 receives a control signal notified from the radio base station 20. The traffic level acquisition unit 133 extracts the traffic level included in the control signal received by the wireless transmission / reception unit 132. The traffic level storage unit 134 stores the traffic level extracted by the traffic level acquisition unit 133 and the traffic level setting information. The traffic level storage unit 134 receives a new control signal, extracts the traffic level by the traffic level acquisition unit 133, and if the traffic level is a new value (if it is different from the already stored value), the newly extracted traffic Remember the level. The traffic level setting information is the same as the data shown in FIG. 3 and is the same information as the traffic level setting information stored in the radio base station 20.

  The transmission determination unit 136 refers to the traffic level storage unit 134 when a transmission request 135 is generated in the terminal station 13, determines whether or not a transmission request is possible according to the traffic level setting information, and determines that transmission is possible, and performs wireless transmission / reception. When a signal corresponding to the transmission request is transmitted via the unit 132 and it is determined that transmission is not possible, a response indicating that transmission is impossible is returned to the transmission source. Here, in response to the generated transmission request, the transmission percentage corresponding to the traffic level (traffic level received from the radio base station 20) stored in the traffic level storage unit 25 is read from the traffic level setting information, and the read transmission percentage is read. According to the probability, it is determined whether or not a signal corresponding to the transmission request can be transmitted. For example, when the traffic level received from the radio base station 20 is “3”, transmission is permitted with a probability of 62.5%, which is the transmission percentage associated with this traffic level “3”.

FIG. 6 is a flowchart for explaining the operation of the radio base station 20.
Here, it is assumed that the initial value of the traffic level is stored in the traffic level storage unit.
The list management unit 22 of the radio base station 20 first performs polling, and generates and stores list A and list B. Here, each time polling is performed, these lists may be updated.
When the list is generated, the traffic measurement unit 23 monitors the communication status of the wireless transmission / reception unit 21 and measures the traffic. Here, the entire traffic is measured by going up and down. When the traffic is measured, the traffic level conversion unit 24 calculates the traffic level according to the above equation (1) based on the measured traffic volume (step S11). When the traffic level is calculated, the traffic level conversion unit 24 calculates the traffic level calculated for the capacity of the wireless section based on the capacity (allowable traffic amount of the system) of the wireless section and the calculated traffic level Lt. The ratio of Lt is calculated, and the calculated value is compared with the upper limit reference value (step S12).
If the calculated value exceeds the upper limit reference value, the traffic level conversion unit 24 lowers the traffic level stored in the traffic level storage unit 25 (step S13). For example, when the traffic level stored in the traffic level storage unit 25 is “3”, the traffic level conversion unit 24 rewrites the traffic level stored in the traffic level storage unit 25 to “2”.

  On the other hand, when the calculated value does not exceed the upper limit reference value, the traffic level conversion unit 24 compares the calculated value with the lower limit reference value (step S14). If the calculated value is less than or equal to the lower limit reference value, the traffic level conversion unit 24 increases the traffic level stored in the traffic level storage unit 25 (step S15). For example, when the traffic level stored in the traffic level storage unit 25 is “3”, the traffic level conversion unit 24 rewrites the traffic level stored in the traffic level storage unit 25 to “4”.

On the other hand, when the calculated value exceeds the lower limit reference value, the traffic level conversion unit 24 does not rewrite the traffic level and maintains the current value.
When the traffic level conversion unit 24 determines the traffic level, the control signal generation unit 26 reads the traffic level stored in the traffic level storage unit 25, and in the control signal of the wireless communication system via the wireless transmission / reception unit 21. Incorporated, and transmitted by the broadcast control signal at the notification timing of the control signal (step S16).

  In the embodiment described above, the traffic amount is calculated according to the equation (1), but may be calculated according to the equation (2).

  In the above-described embodiment, the case where the traffic level setting information shown in FIG. 3 is used has been described. However, the traffic level setting information shown in FIG. 4 may be transmitted to the terminal station to control the traffic amount. .

  In addition, a program for realizing the function of the radio base station 20 in FIG. 1 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed to execute a traffic level. The decision may be made. Here, the “computer system” includes an OS and hardware such as peripheral devices.

Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory in a computer system serving as a server or a client in that case, and a program that holds a program for a certain period of time are also included. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes designs and the like that do not depart from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 Communication area 20 Wireless base station 13, 14, 15, 16, 17, 18 Terminal station 21 Wireless transmission / reception part 22 List management part 23 Traffic measurement part 24 Traffic level conversion part 25 Traffic level memory | storage part 26 Control signal generation part 27 Transmission determination 28 Traffic level reference / change interface

Claims (5)

A base station apparatus in a radio communication system in which a base station apparatus that communicates with the terminal station determines a transmission permission probability value of the terminal station according to a plurality of traffic levels,
A first group that is a group of terminal stations that have been accessed or have been confirmed within a predetermined time period for a terminal station that is under its control, and a group that is a terminal station that has not been confirmed to have been accessed or located within a predetermined time period. A group management unit for classifying the group into two groups;
A traffic amount prediction unit for predicting a traffic amount generated by a terminal station belonging to the first group and a traffic amount generated by a terminal station belonging to the second group;
A calculation unit for calculating a weighted average value of the obtained predicted traffic amount as next traffic;
When the calculated next traffic is greater than or equal to a predetermined upper limit, the traffic level is changed from the current value to a traffic level that tightens transmission restrictions of the terminal station, and the next traffic is less than or equal to a predetermined lower limit. A traffic level update unit that changes the level from a current value to a traffic level that weakens transmission restrictions of the terminal station;
A traffic level transmitting unit that transmits the traffic level updated by the traffic level updating unit to each of the terminal stations;
A base station apparatus comprising: It has a measurement unit that measures the amount of traffic with which its own radio base station communicates,
2. The base according to claim 1, wherein the traffic amount prediction unit predicts a next traffic amount based on the predicted traffic amount obtained by the prediction and the traffic amount measured by the measurement unit. Station equipment. A setting information storage unit that stores setting information that is information in which a traffic level and the transmission permission probability are associated with each other;
A traffic level storage unit for storing a traffic level after being updated by the traffic level update unit;
A transmitter for transmitting data to the terminal station;
A transmission determination unit that, when transmitting data from the transmission unit, reads a transmission permission probability corresponding to a traffic level stored in the traffic level storage unit, and permits transmission from the transmission unit according to the read transmission permission probability When,
The radio base station according to claim 1 or 2, characterized by comprising: A wireless communication system in which a base station apparatus that communicates with the terminal station determines a value of a transmission permission probability of the terminal station according to a plurality of traffic levels,
The base station device
A first group that is a group of terminal stations that have been accessed or have been confirmed within a predetermined time period for a terminal station that is under its control, and a group that is a terminal station that has not been confirmed to have been accessed or located within a predetermined time period. A group management unit for classifying the group into two groups;
A traffic amount prediction unit for predicting a traffic amount generated by a terminal station belonging to the first group and a traffic amount generated by a terminal station belonging to the second group;
A calculation unit for calculating a weighted average value of the obtained predicted traffic amount as next traffic;
When the calculated next traffic is greater than or equal to a predetermined upper limit, the traffic level is changed from the current value to a traffic level that tightens transmission restrictions of the terminal station, and the next traffic is less than or equal to a predetermined lower limit. A traffic level update unit that changes the level from a current value to a traffic level that weakens transmission restrictions of the terminal station;
A traffic level transmission unit that transmits the traffic level updated by the traffic level update unit to each of the terminal stations;
The terminal station
A setting information storage unit that stores setting information that is information in which a traffic level and the transmission permission probability are associated with each other;
A traffic level storage unit for receiving and storing a traffic level transmitted from the radio base station;
A terminal station transmitter for transmitting data to the radio base station;
When transmitting data from the terminal station transmission unit, the transmission permission probability corresponding to the traffic level stored in the traffic level storage unit is read, and transmission from the terminal station transmission unit is permitted according to the read transmission permission probability A transmission determination unit to perform,
A wireless communication system comprising: A method for determining a traffic level of a radio base station in a radio communication system in which a base station apparatus that communicates with the terminal station determines a value of a transmission permission probability of a terminal station according to a plurality of traffic levels,
The group management unit of the radio base station,
A first group that is a group of terminal stations that have been accessed or have been confirmed within a predetermined time period for a terminal station that is under its control, and a group that is a terminal station that has not been confirmed to have been accessed or located within a predetermined time period. Into two groups,
The traffic amount prediction unit of the radio base station
Predicting the amount of traffic generated by terminal stations belonging to the first group and the amount of traffic generated by terminal stations belonging to the second group, respectively;
The calculation unit of the radio base station,
Calculate the weighted average of the obtained predicted traffic volume as the next traffic,
The traffic level update unit of the radio base station,
When the calculated next traffic is greater than or equal to a predetermined upper limit, the traffic level is changed from the current value to a traffic level that tightens transmission restrictions of the terminal station, and the next traffic is less than or equal to a predetermined lower limit. Change the level from the current value to a traffic level that weakens the terminal station transmission regulations,
The traffic level transmission unit of the radio base station,
A traffic level determination method for a radio base station, wherein the traffic level updated by the traffic level update unit is transmitted to each terminal station.

Images