JP2001308914A - Base station unit for wireless packet communication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a wireless base station unit for a wireless packet communication system that can maintain the impartiality of access opportunities among users when a wireless base station for wireless packet communication and a subscriber station conduct data transmission. SOLUTION: The base station unit of this invention is provided with a means that uses a transmission queue with the lowest priority in a transmission buffer for the transmission of data of a limit class as its control, a cross-reference table of transmission queues used when data are transmitted by each service class, a service class management table that manages each service class by each subscriber station at transmission of non-priority data, a statistic data acquisition means that calculates statistics of the non-priority data by each subscriber station under the control at the arrival of data transmitted as a non-priority class, and a means that changes a service class into a limit class at the transmission of the non-priority data addressed to the subscriber station when a state in which data amount (arrival rate) per unit time of the non- priority data arrived at the address of the subscriber station exceeds a threshold value R1 exceeds a time T1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for transmitting data between a radio base station and a subscriber station by radio packet communication.
The present invention relates to a wireless base station device of a wireless packet communication system that maintains fairness of access opportunities between users by using priority control.

[0002]

2. Description of the Related Art Conventional priority control methods for data transmission include an IEEE standard defined by the IEEE802 committee.
A method using 802.1D Annex H is known. An outline of this method is shown in FIG. IEEE802.1D Annex H is a protocol on a wired system, and Ethernet (registered trademark) generally used in a LAN in an office or the like.
It is intended for.

According to the method defined in IEEE 802.1D Annex H, priority control is performed by defining a field indicating a priority in a header portion of an Ethernet frame and performing queuing in consideration of the priority in a bridge device. IEEE802.
A data relay device (hereinafter referred to as a bridge) that conforms to 1D Annex H has a maximum of seven transmission queues for temporarily storing data to be relayed, and each transmission queue has a capacity depending on the quality of the service to be provided. Priority is set.

[0004] In a communication system according to IEEE 802.1D Annex H, a field indicating the priority of the frame is provided in a data frame to be transmitted and received, and the bridge also has a priority set in the data frame to be relayed. At this time, the data frames are stored in an appropriate transmission queue according to the priority. The bridge extracts data from a transmission queue according to a specified algorithm and performs transmission.

[0005] Although there is no specific rule regarding the algorithm at this time, WFQ (Weig
hted Faire Queuing) and WRR (Weighted Round-Robi)
An algorithm based on existing methods such as n) is used. On the other hand, the correspondence between the quality of the service to be provided and the priority of the transmission data queue is described in IEEE802.1D AnneX H, and the service class for best-effort data normally used on the Internet is the most. It is associated with a transmission data queue having a low priority.

That is, normal data transmitted and received on the Internet, such as mail and www, is transmitted at the lowest priority, and data such as voice and moving images that require real-time performance is transmitted at a higher priority. It works. As an example of a conventional wireless communication system having a priority control function,
There are systems defined by the IEEE 802.11 committee.

FIG. 12 shows the outline. IEEE802.11
In the system, the channel is a DCF (Distributed Coor
CSMA / CA (Carr called dination Function)
ierSense Multiple Access withC0llsion Avoidance:
Contention access period using collision avoidance type carrier detection multiple access (PC) protocol and PCF (Point CoordinationFu)
nction) is temporally separated during a period in which the radio base station performs centralized access control using polling. Best-effort data is sent by DCF, and priority data is sent by PCF.

FIG. 12 shows an example of an IEEE 802.11 system.
This shows an example in which the wireless base station 100 transmits and receives data to and from the subscribed subscriber stations 200 to 202. The rectangles represent signals, and the ones with D inside are data, P is polling, A is acknowledgment (ACK)
It is a frame.

The channel has a period of time interval TI,
PCF and DCF are set within that period. In the figure, the radio base station 100 is transmitting downlink data to the subscriber station 200 during the PCF period,
Also, it receives uplink data from the subscriber station 201.

At this time, the subscriber station 201 is allowed to transmit data only when polled from the radio base station 100, and in FIG.
It is for this reason that 1 receives the polling frame from the wireless base station 100 before transmitting data.

On the other hand, during the DCF, polling signals are not transmitted because data is transmitted according to a random access procedure called the CSMA / CA protocol, and a station that has obtained a transmission right due to contention transmits data. However, in the IEEE802.11 standard, means for managing the priority of each data is not prepared, and it is necessary to implement some method for performing the priority control in the PCF.

[0012]

Heretofore, priority data has been transmitted and received using the above-described method. On the Internet, best-effort services are mainstream, and data for e-mail and web browsing is sent on a best-effort basis. According to the conventional priority control method, the best-effort service transmitted and received on the Internet is performed using the transmission data queue having the lowest priority.

[0013] Therefore, when a specific user sends and receives a large amount of data in the best-effort communication, there is a problem that data transmission and reception of other users are hindered. An object of the present invention is to provide a wireless communication system capable of maintaining fairness of access opportunities between users by using priority control in order to solve such a conventional problem.

[0014]

According to the present invention, the above-mentioned object is solved by the means described in the claims. That is, the invention according to claim 1 includes a radio base station having a data relay function and a subscriber station that transmits and receives data to and from the radio base station. When arrives, according to the priority information of the data added to the received data, the data is allocated to the transmission buffer of the corresponding priority,

[0015] Further, there is provided scheduling means for taking out data from the transmission buffer and transmitting the data in accordance with a predetermined algorithm. Inside the scheduling means, services for providing different communication quality (hereinafter referred to as service classes) are provided. It has a transmission buffer composed of a plurality of transmission queues having different priorities corresponding to the respective service classes, and the radio base station performs data transfer to the subordinate subscriber stations while reflecting the data priority. A wireless packet communication base station device used in a wireless communication system,

A service class for transmitting priority data and a service class for transmitting non-priority data are defined. Best-effort data that is usually used is used as a service class for transmitting non-priority data. When there is a service class (best effort class) for sending and a lower service class (restriction class),

Means for controlling the transmission queue of the lowest priority in the transmission buffer to be used for transmitting data of the restriction class, and a correspondence table of transmission queues used when transmitting data in each service class And a service class management table for managing a service class for transmitting non-priority data for each subscriber station, and, when data to be transmitted in the non-priority class arrives, the statistics of the non-priority data are reported to each of the subordinate subscribers. Statistical data acquisition means for calculating for each station;

Data amount per unit time of non-priority data arriving at a certain subscriber station (hereinafter referred to as arrival rate)
Means for changing the service class for transmitting non-priority data to the subscriber station to the restricted class when the state exceeding the threshold value R1 exceeds the time period T1. It is a station device.

[0019] The invention of claim 1 is characterized by:
When the wireless base station transmits non-priority data to subordinate subscriber stations, a service class lower than the normally used best effort class is provided. The service class at the time of transmitting the priority data is managed using the service class management table, and the data amount per unit time of the non-priority data arriving for each subscriber is obtained by the statistical data acquisition means, A transmission rate for a certain subscriber station is a predetermined threshold value R.
When the state exceeding 1 exceeds the time T1, the service class for transmitting non-priority data to the subscriber is changed to the restriction class, that is, the priority of data transmission to the subscriber station is reduced. Are different.

According to a second aspect of the present invention, in the wireless packet communication base station apparatus according to the first aspect, when the wireless base station transmits non-priority data to a certain subscriber station, the wireless base station transmits the data in a restricted class. When it is observed that the arrival rate of the non-priority data addressed to the transmitting subscriber station is less than the threshold value R2 for a time T2 or more, the non-priority data is transmitted to the subscriber station. The service class at the time of transmission is provided with means for changing to a best effort class.

According to the second aspect of the present invention,
2. The arrival rate of non-priority data addressed to a subscriber station transmitting data in a restricted class by a radio base station to a subscriber station whose priority has been downgraded, according to claim 1. Changes the service class for transmitting non-priority data to the subscriber station to the best-effort class when the state of falling below the threshold value R2 continues for a time T2 or more.
That is, the difference is that the wireless base station has a function of restoring a service class once downgraded to a subordinate subscriber.

According to a third aspect of the present invention, in the base station for wireless packet communication according to the second aspect of the present invention, a counter is provided inside the statistical data acquisition means, and a variable corresponding to each subscriber station under the counter is provided in the counter. When calculating the arrival rate for each subscriber station, calculate the amount of non-priority data arriving within the time Ts at each time interval Ts, and divide the amount of the non-priority data by the Ts, that is, Means for determining, for each subscriber station, the average arrival rate within the time interval Ts;

When the average arrival rate of the non-priority data to the subscriber station transmitting the non-priority data in the best-effort class exceeds a threshold value R1, a variable corresponding to the subscriber station in the counter is set in the counter. 1 is added, otherwise, the variable is set to 0, and when the variable becomes N, that is, a state where the arrival rate of non-priority data arriving at the subscriber station exceeds the threshold R1 Is time T1
(T1 = N × Ts, N = 1, 2, 3,...) If the continuation continues, the service class of the non-priority data to be transmitted to the subscriber station is changed to a restricted class;

When non-priority data is transmitted in a restricted class to a certain subscriber station, when the average arrival rate of non-priority data arriving at the subscriber station falls below a threshold value R2. Adds 1 to the variable, otherwise sets it to 0, and when the variable reaches M, ie, the average arrival rate of non-priority data arriving at the subscriber station is equal to the time T2 ( T2 = M × Ts, where M = 1, 2,
3,...) Means for changing the service class when transmitting non-priority data to the subscriber station to the best-effort class when the value continuously drops below the threshold value R2. It is.

The third aspect of the present invention is different from the prior art in that when the radio base station calculates the arrival rate to the subscriber station at each time interval Ts, it calculates the data amount of the non-priority data. , An average arrival rate within the time interval Ts, and the average arrival rate and a threshold R
1 and R2, and the result of the comparison is stored in a variable in the counter, and based on the service class at the time of non-priority data transmission to each subscriber station and the value of the variable, The difference is that the service class is changed when transmitting non-priority data.

A fourth aspect of the present invention comprises a radio base station having a data relay function and a subscriber station for transmitting and receiving data to and from the radio base station. When the data arrives, the data is distributed to the transmission buffer of the corresponding priority according to the priority information of the data added to the received data, and the data is extracted from the transmission buffer according to a predetermined algorithm and transmitted. A transmission buffer configured to provide services of different communication qualities (service classes) and having a plurality of transmission queues having different priorities corresponding to the respective service classes. Wireless base station that transmits data to subordinate subscriber stations while reflecting the priority of data. A radio packet communication base station apparatus used in the system, wherein a service class for transmitting priority data and a service class for transmitting non-priority data are defined, and a service for transmitting non-priority data is provided. When there are a service class (best effort class) for transmitting normally used best effort data and a service class (restriction class) lower than that, a transmission queue having the lowest priority in the transmission buffer. Means for controlling transmission of data of the restriction class, a correspondence table of transmission queues used when transmitting data in each service class,
A service class management table for managing a service class for transmitting non-priority data for each subscriber station, and means for obtaining statistics of data transmitted in the non-priority class for each subscriber station (hereinafter referred to as statistical data acquisition means) When the state in which the data transmission rate when transmitting data to a certain subscriber station in the best effort class exceeds the threshold value R3 exceeds the time T3, non-priority is given to the subscriber station. Means for changing a service class for transmitting data to a restricted class.

The invention of claim 4 is different from the prior art in that
When the wireless base station transmits non-priority data to subordinate subscriber stations, a service class lower than the normally used best effort class is provided. The service class for transmitting the priority data is managed by using the service class management table, and the transmission speed at the time of transmitting the non-priority data for each subscriber is obtained by the statistical data acquisition means, and a certain subscription is obtained. If the state in which the transmission rate for the subscriber station exceeds the prescribed threshold value R3 exceeds the time T3, the service class for transmitting non-priority data to the subscriber is changed to the restricted class, that is, the subscription The difference is that the priority of data transmission to the remote station is lowered.

According to a fifth aspect of the present invention, in the wireless packet communication base station apparatus according to the fourth aspect, when the wireless base station transmits non-priority data to a certain subscriber station, the wireless base station transmits the data in a restriction class. If it is observed that the state in which the data transmission rate for the transmitting subscriber station is lower than the threshold value R4 continues for a time T4 or more, the service class for transmitting non-priority data to the subscriber station is changed. , A means for changing to the best-effort class is provided.

The invention according to claim 5 is different from the prior art in that, in addition to the features described in claim 4, the radio base station gives the radio base station to the subscriber station whose priority has been downgraded. If the transmission rate of the non-priority data transmitted to the subscriber station is below the threshold value R4 for a time T4 or more, the service class for transmitting the non-priority data to the subscriber station is best. The difference is that the service class is changed to an effort class, that is, the radio base station has a function of restoring a service class once downgraded to a subordinate subscriber.

According to a sixth aspect of the present invention, in the base station apparatus for wireless packet communication according to the fifth aspect, a counter is provided inside the statistical data acquisition means, and a variable corresponding to each subscriber station under the counter is provided in the counter. When calculating the data transmission rate for each subscriber station, the time T
s, and calculates the amount of non-priority data transmitted within s and divides the non-priority data amount by the Ts, ie, the time interval
Means for determining the average transmission rate in each subscriber station for each subscriber station; and means for determining whether the average transmission rate of non-priority data transmitted to a certain subscriber station in the best-effort class exceeds a threshold value R3. Add 1 to the variable corresponding to the subscriber station in the counter, otherwise set the variable to 0, and when the variable becomes N, ie, the non-priority data for the subscriber. The state in which the transmission speed when transmitting the data exceeds the threshold value R3 is time T3 (T3 = N × Ts, N =
Means for changing the service class of the non-priority data to be transmitted to the subscriber station to the restricted class when the data is consecutively transmitted to the subscriber station; When transmitting non-priority data, the average transmission rate of non-priority data to the subscriber station is equal to a threshold R
If it is less than 4, add 1 to the variable, otherwise set it to 0, if the variable reaches M, ie the transmission rate of non-priority data sent to the subscriber station Is the time T4 (T4 = M × Ts, where M = 1, 2,
(3,...) In the case where the value continuously drops below the threshold value R4, means for changing the service class for transmitting non-priority data to the subscriber station to the best effort class is provided. Things.

[0031] The invention of claim 6 differs from the prior art in that
A point at which the radio base station totals the amount of data transmitted to the subordinate subscriber stations at each time interval Ts, and obtains an average transmission rate within the time interval Ts. The points to be compared with the values R3 and R4 and the result of the comparison are stored in variables in the counter, and each subscriber station is determined from the service class at the time of non-priority data transmission to each subscriber station and the value of the variable. In that a service class is changed when transmitting non-priority data to a service.

[0032] The invention of claim 7 is based on claim 2, claim 3,
The base station apparatus for wireless packet communication according to any one of claims 5 or 6, further comprising: a subscriber station operating status management unit that manages an operating status of each subordinate subscriber station;
When transmitting non-priority data to a subordinate subscriber station, the control of the part for changing the service class from the best effort class to the restricted class in the procedure for changing the service class is controlled by K of the subordinate subscriber stations. It is configured by providing a means for limiting to a case where at least stations are in operation.

[0033] The invention according to claim 7 is characterized in that the radio base station has subscriber station operation status management means, and the downgrade of the service class when transmitting non-priority data to a certain subscriber station. The conventional technique, and the second, third, fifth, and fifth aspects of the present invention limit processing to be performed when a predetermined number of subscriber stations among the subordinate subscriber stations are operating.
Alternatively, the technology is different from the technology described in any one of claims 6.

[0034]

FIG. 1 is a diagram showing a first example of an embodiment of the present invention. This example is based on claim 1 and
7 shows a configuration of a wireless base station according to the second aspect of the present invention. In the figure, solid arrows indicate the flow of data,
The dashed arrows indicate the flow of control. Wireless base station 100
Means the scheduling means 110, the reception processing means 12
0, relay processing means 130, access control means 140, and lower layer processing means 150 for performing modulation processing and the like. This figure shows a case where the relay processing unit 130 is not included in the data link layer, but the relay processing unit 130 may be included in the data link layer.
This is the same for the other drawings described below.

The object of the present invention is a part of the scheduling means 110. Scheduling means 110
Holds a transmission buffer 111 composed of a plurality of queues having different priorities, a service class and queue priority correspondence table 112, and a service class for transmitting non-priority data to subordinate subscriber stations. It has a service class management table 113 and statistical data acquisition means 114 for obtaining statistics on the amount of data transmitted and received between each subscriber station.

FIG. 2 is a flowchart for explaining the control according to the first and second aspects of the present invention. The process illustrated in FIG. 2 is performed until the scheduling unit 110 in the wireless base station 100 illustrated in FIG. 1 passes the data passed from the relay processing unit 130 to the access control unit 140. The scheduling means 110
If the relay data has arrived (S001), step S0
At 02, the priority information described in the header part of the relay data is read, and the service quality is analyzed.

Next, in step S003, it is determined from the result of the analysis whether the data should be given priority. Here, if the relay data is data to be given priority, the flow proceeds to step S004, and the transmission buffer 1
11, buffered in the appropriate queue in S010
Then, it is determined whether or not data is accumulated in the transmission buffer 111. When data is stored in the transmission buffer 111, transmission processing is performed in S010. On the other hand, if the relay data is the non-priority data, the process proceeds to step S005, where the service class provided to the destination subscriber station is stored in the service quality management table 1.
Inspect 13

If the transmission of the non-priority data to the destination subscriber station is designated as the best effort class, the data is buffered in a priority queue corresponding to the service of the best effort class. on the other hand,
If the transmission of the non-priority data to the destination subscriber station is specified as the restriction class, the relay data is buffered in the queue having the lowest priority (step S006).

Then, the flow advances to step S007 to perform statistical data processing on the destination subscriber station of the data. That is, the amount of data arriving from the subscriber station is updated,
A data arrival rate from the subscriber station is calculated. Next, in step S008, the statistical information of the destination subscriber station is compared with a specified value, and it is determined whether to change the service class when transmitting data to the subscriber station.

If it is confirmed that the state in which the data arrival rate exceeds the threshold value R1 has continued for a time T1 or more, the flow advances to step S009 to provide a service class for transmitting data to the destination subscriber station. Is changed to the restriction class. The service class determined here is recorded in the service class management table 113. Then, in step S010, it is determined whether or not data is accumulated in the transmission buffer 111. At this time, if no data is stored in the transmission buffer 111, the process returns to step S001. On the other hand, the transmission buffer 1
If data has been stored in step S0, the process proceeds to step S0.
Then, the data is extracted according to a prescribed algorithm while considering the priority of the queue, and is passed to the access control means 140. Thereafter, the data is passed to the lower layer processing means 150 and transmitted.

The second aspect of the present invention differs from the first aspect of the present invention in the part after the statistical data processing is performed in step S007 in FIG. Here, the invention described in claim 2 is treated as a second example of the embodiment of the present invention. In this example, in the process of step S008, first, as in the case of the first aspect of the present invention, the state in which the arrival rate of the non-priority data of the best effort class to a certain subscriber exceeds the threshold value R1 is time. If T1 or more continues, the service class for transmitting the non-priority data to the subscriber is changed from the best effort class to the restriction class.

Further, when the arrival rate of the non-priority data received in the restriction class is equal to or less than the threshold value R2 for a time T2 or more, the non-priority data is transmitted to the subscriber station. The service class is changed to the best-effort class. The change of the service class at the time of transmitting the non-priority data to the subscriber station by the above processing is recorded in the service class management table.

FIG. 3 is a diagram showing a third example of the embodiment of the present invention, and shows a configuration of a radio base station according to the third aspect. According to the third aspect of the present invention, in addition to the configuration shown in FIG. 1, the radio base station includes, in the statistical data acquisition means 114, a counter 115 for obtaining statistics when transmitting non-priority data for each subscriber, The means 110 has a timer-116.

The counter 115 is provided with variables corresponding to the number of subordinate subscriber stations, and sets the average transmission rate when non-priority data is transmitted to each subscriber station at a predetermined time interval Ts. The result of the comparison with the value is retained. Further, the timer-116 times out at regular time intervals Ts, and the scheduling means 110 calculates statistical data by taking this time.

FIG. 4 is a flowchart showing a control in a third example of the embodiment of the present invention. The process illustrated in FIG. 4 is performed until the scheduling unit 110 in the wireless base station illustrated in FIG. 3 passes the data passed from the relay processing unit 130 to the access control unit 140. According to the third aspect of the present invention, the radio base station performs statistical data processing at regular time intervals when calculating the arrival rate of data from the subordinate subscriber stations. Is required.

The scheduling means 110 starts the timer-116 in step S101, and proceeds to the next step S1.
In step 02, it is confirmed whether or not relay data has arrived from the relay processing means 130. At this time, if the relay data has not arrived, the process proceeds to step S109. If the relay data has arrived, the process proceeds to step S103. In step S103, the priority information described in the header portion of the relay data is read, and the service quality is analyzed.

Thereafter, in step S104, it is determined whether or not the relay data is priority data. If the relay data is priority data, the flow advances to step S105 to be buffered in an appropriate queue. On the other hand, if the relay data is not priority data in the determination in step S104, the process proceeds to step S106, where the destination of the relay data is referred to, and the service quality allowed for the destination subscriber station is managed by the service quality management. Check according to Table 113.

Thereafter, the process proceeds to step S107, and if the destination subscriber is permitted to use the service in the best effort class according to the inspection result in the previous step S106, the relay data is buffered in the queue of the corresponding priority. If the service class for transmitting non-priority data to the destination subscriber station is a restricted class, the relay data is buffered in a queue having the lowest priority.

Then, the flow advances to step S108 to perform statistical data processing on the destination subscriber station of the data. Next, the process proceeds to step S109, and it is determined whether data is accumulated in the transmission buffer. If no data is stored in the transmission buffer, the process proceeds to step S11. On the other hand, when data is accumulated in the transmission buffer, the process proceeds to step S110,
Data is taken out according to a prescribed algorithm while considering the priority of the queue, and is passed to the access control means.

Thereafter, the flow advances to step S111 to check whether or not the timer-116 started in step S101 has timed out. If the timer-116 has not timed out, the process returns to step S102, and the above processing is repeated. On the other hand, when the timer-116 has timed out, the process proceeds to the next step S112.

In step S112, the average arrival rate for the non-priority data arriving at each subscriber station is calculated. At this time, the average arrival rate of the non-priority data arriving at each subscriber station in the best effort class is compared with a threshold value R1. If the average arrival rate of the subscriber station performing the non-priority data in the best effort class is equal to or less than the threshold value R1, the variable for the subscriber station in the counter 115 is set to 0.

On the other hand, if the average arrival rate for the subscriber station exceeds the threshold value R1, the counter 115
Add 1 to the variable for the subscriber station in. At this time, if the variable for the subscriber station exceeds N, the radio base station changes the service class when transmitting non-priority data to the subscriber station to a restricted class. I do. On the other hand, the average transmission rate for the subscriber station transmitting non-priority data in the restriction class is compared with a threshold value R2.

The average data arrival speed from the subscriber station transmitting the non-priority data in the restricted class is equal to the threshold value R2.
If so, the variable for the subscriber station in counter 115 is set to zero. On the other hand, when the average data arrival speed from the subscriber station falls below the threshold value R2, 1 is added to the variable for the subscriber station in the counter 115. At this time, if the variable for the subscriber station exceeds M, the radio base station changes the service class when transmitting non-priority data to the subscriber station to a best effort class.

When the processing of step S112 is completed and the radio base station determines a service class for transmitting non-priority data to the respective subordinate subscriber stations during the next time interval Ts, In step S113, the result is reflected in the service class management table 113. When step S113 ends, the process returns to step S101, and the above process is repeated.

FIG. 5 is a diagram showing a fourth example of the embodiment of the present invention. This example corresponds to claims 4 and 5
2 shows a configuration of a wireless base station corresponding to the invention described in (1). In the figure, a solid arrow indicates a data flow, and a broken arrow indicates a control flow. The radio base station 100 includes a scheduling unit 110, a reception processing unit 120, a relay processing unit 130, an access control unit 140, and a lower layer processing unit 150.

The object of the present invention is a part of the scheduling means 110. Scheduling means 110
Holds a transmission buffer 111 composed of a plurality of queues having different priorities, a service class and queue priority correspondence table 112, and a service class for transmitting non-priority data to subordinate subscriber stations. It has a service class management table 113 and statistical data acquisition means 114 for obtaining statistics on the amount of data transmitted and received between each subscriber station.

FIG. 6 is a flowchart for explaining the control of the fourth example of the embodiment of the present invention. The process illustrated in FIG. 6 is performed until the scheduling unit 110 in the wireless base station 100 illustrated in FIG. 5 passes the data passed from the relay processing unit 130 to the access control unit 140. When the relay data arrives, in step S002, the scheduling unit 110 reads and analyzes the priority information described in the header of the relay data.

Next, in step S003, it is determined from the result of the analysis whether the data should be given priority. Here, if the relay data is data to be given priority, the flow proceeds to step S004, and the transmission buffer 1
11 is buffered in the appropriate queue. On the other hand, if the relay data is non-priority data, the process proceeds to step S005, where the service quality provided to the destination subscriber station is checked by the service quality management table 113.

When the transmission of the non-priority data to the destination subscriber station is designated as the best effort class, the data is buffered in a priority queue corresponding to the service of the best effort class. on the other hand,
If the transmission of the non-priority data to the destination subscriber station is specified as the restriction class, the relay data is buffered in the queue having the lowest priority (step S006).

Next, the process proceeds to step S007, where it is determined whether or not data is stored in the transmission buffer 111. At this time, if no data is stored in the transmission buffer 111, the process returns to step S001. On the other hand, if data is stored in the transmission buffer 111, the process proceeds to step S008, where the data is extracted according to a prescribed algorithm while considering the priority of the queue, and transferred to the access control means 140.

After transferring the data to the access control means 140, the flow advances to step S009 to perform statistical data processing on the destination subscriber station of the data. That is, the amount of data transmitted to the destination subscriber station is updated, and the data transmission speed to the subscriber station is calculated. Next, in step S010, the statistical information of the destination subscriber station is compared with a prescribed value, and it is determined whether to change the service class when transmitting data to the subscriber station.

If it is confirmed that the state in which the data transmission rate exceeds the threshold value R1 continues for the time T1 or more, the flow advances to step S011 to indicate a service class for transmitting data to the destination subscriber station. Is changed to the restriction class. The service class determined here is recorded in the service class management table 113. Thereafter, the data is passed to the lower layer processing means 150 and transmitted.

The invention according to claim 5 differs from the invention according to claim 4 in the part after performing the statistical data processing in step S009 of FIG. Here, the invention described in claim 5 is treated as a fifth example of the embodiment of the present invention. In this example, if the state in which the data transmission rate to the subscriber station transmitting the non-priority data in the best-effort class exceeds the threshold value R1 continues for a time T1 or more in the process of step S010, The service class for transmitting non-priority data to the subscriber is changed from the best effort class to the restricted class.

If the data transmission rate to the subscriber station transmitting the non-priority data in the restricted class continues for a period of time T2 or less, which is equal to or less than the threshold value R2, the non-priority data is transmitted to the subscriber station. A process of changing the service class when transmitting the priority data to the best effort class is performed.
The change of the service class at the time of transmitting the non-priority data to the subscriber station by the above processing is recorded in the service class management table.

FIG. 7 is a diagram showing a sixth example of the embodiment of the present invention, and shows a configuration of a radio base station according to claim 6. According to the sixth aspect of the present invention, in addition to the configuration shown in FIG. 1, the radio base station includes, within the statistical data acquisition means 114, a counter 115 for obtaining statistics when transmitting non-priority data for each subscriber, The means 110 has a timer-116.

The counter is provided with variables corresponding to the number of subordinate subscriber stations, and the average transmission rate and the threshold value when non-priority data is transmitted to each subscriber station at fixed time intervals Ts. The result of comparison with is retained. Further, the timer-116 times out at regular time intervals Ts, and the scheduling means 110 calculates statistical data by taking this time.

FIG. 8 is a flowchart showing the control of the sixth example of the embodiment of the present invention. The process illustrated in FIG. 8 is performed until the scheduling unit 110 in the wireless base station illustrated in FIG. 6 passes the data passed from the relay processing unit 130 to the access control unit 140. According to the third aspect of the present invention, when the radio base station calculates the average transmission rate for the subordinate subscriber stations, it processes statistical data at regular time intervals, so that time management using a timer is required. Becomes

The scheduling means 110 starts the timer-116 in step S101, and proceeds to the next step S1.
In step 02, it is confirmed whether or not relay data has arrived from the relay processing means 130. At this time, if the relay data has not arrived, the process proceeds to step S108, and if the relay data has arrived, the process proceeds to step S103. In step S103, the priority information described in the header portion of the relay data is read, and the priority is analyzed.

Thereafter, in step S104, it is determined whether or not the relay data is priority data. If the relay data is priority data, the flow advances to step S105 to be buffered in an appropriate queue. On the other hand, if the relay data is not priority data in the determination in step S104, the process proceeds to step S106, where the destination of the relay data is referred to, and the service quality allowed for the destination subscriber station is managed by the service quality management. Check according to Table 113.

Thereafter, the process proceeds to step S107, and if the destination subscriber is permitted to use the service in the best effort class according to the inspection result in the previous step S106, the relay data is buffered in the queue of the corresponding priority. If the service class for transmitting non-priority data to the destination subscriber station is a restricted class, the relay data is buffered in a queue having the lowest priority. Next, the process proceeds to step S108,
It is determined whether data is accumulated in the transmission buffer.

If no data is stored in the transmission buffer, the process proceeds to step S11. On the other hand, if data is accumulated in the transmission buffer,
Proceeding to step S109, data is extracted according to a prescribed algorithm while taking into account the priority of the queue, and is passed to the access control means. After delivering the relay data to the access control means 140, the process proceeds to step S110, where statistical data processing is performed on the destination subscriber station of the data.

In the sixth embodiment of the present invention, when processing statistical data, the amount of data transmitted to the destination subscriber station is updated. Then, step S11
1 and the timer-116 started in step S101.
Is checked to see if it has timed out. The timer
If 116 has not timed out, step S1
02, and the above processing is repeated. On the other hand, when the timer-116 has timed out, the process proceeds to the next step S112.

In step S112, the average transmission rate for each subscriber station is calculated. At this time, the average transmission rate of the subscriber station transmitting the non-priority data in the best effort class is compared with the threshold value R1. If the average transmission rate for the subscriber station transmitting the non-priority data in the best effort class is equal to or less than the threshold value R1, the variable for the subscriber station in the counter 115 is set to 0.

On the other hand, if the average transmission rate for the subscriber station exceeds the threshold value R1, one is added to the variable for the subscriber station in the counter 115. At this time, if the variable for the subscriber station exceeds N, the radio base station changes the service class when transmitting non-priority data to the subscriber station to a restricted class. I do.
On the other hand, the average transmission rate for the subscriber station transmitting non-priority data in the restriction class is compared with a threshold value R2.

If the average transmission rate for the subscriber station transmitting non-priority data in the restricted class is equal to or greater than the threshold value R2, the variable for the subscriber station in the counter 115 is set to 0. Is done. On the other hand, when the average transmission rate for the subscriber station falls below the threshold value R2, one is added to the variable for the subscriber station in the counter 115. At this time, if the variable for the subscriber station exceeds M,
The radio base station changes a service class for transmitting non-priority data to the subscriber station to a best effort class.

When the processing of step S112 is completed and the radio base station determines a service class for transmitting non-priority data to the respective subordinate subscriber stations during the next time interval Ts, In step S113, the result is reflected in the service class management table 113. When step S113 ends, the process returns to step S101, and the above process is repeated.

FIG. 9 is a diagram showing a seventh example of the embodiment of the present invention, and shows a configuration of a radio base station according to claim 7. According to the seventh aspect of the present invention, the wireless base station includes a subscriber station operation status management unit 117 in addition to the configurations shown in FIGS. The operation status management means 11
In step 7, by referring to the source address of the data received from the subordinate subscriber station, the operation status of the subscribed subscriber station is sequentially grasped.

FIG. 10 is a flowchart for explaining the control of the seventh example of the embodiment of the present invention. As is clear from the figure, this control has substantially the same processing procedure as the control of FIG. 8 described above. For the control of FIG.
The processing of step S108 is added, and as a result, the display of the processing of steps S108 to S113 in FIG.
The only difference is that steps S109 to S114 are changed.

In the figure, the process of updating the statistical data is in steps S108 and S111.
In the process of 108, the statistical data related to the arrival rate is updated, and in step S111, the statistical data related to the transmission speed is updated. Each of these statistical data is analyzed in response to a timeout in step S112, and when both criteria are satisfied, a service class change process is performed in step S113. The other control is the same as in the case of FIG. 8 described above, and the description is omitted.

[0080]

Since the present invention has the above-described structure, it has the following advantages. That is, according to the first and fourth aspects of the present invention, when the wireless base station transmits non-priority data while providing a service to the data to be prioritized with specified communication quality, The station manages the communication quality for each subscriber station and at the same time performs data transfer using priority control,
It is possible to prevent data from being occupied by frequency resources by transmitting data only to specific subscriber stations under its control.

According to the second and fifth aspects of the present invention,
In addition to the above effects, by performing priority control by the radio base station, the subscriber station that has reduced the priority at the time of non-priority data transmission,
Priority can be restored. Therefore, it is possible to prevent the subscriber station whose priority has been lowered at a certain point in time from suffering disadvantages in subsequent data transmission and reception.

According to the third and sixth aspects of the present invention,
When the radio base station monitors the communication quality for the subscribed subscriber station, the average data arrival rate for each fixed time or
By using the average data transmission speed, it is possible to simplify the calculation at the time of obtaining the statistical data.

According to the seventh aspect of the present invention, in the second, third, fifth and sixth aspects of the present invention, the service of the non-priority data to the subscriber having the radio base station is provided. Limiting the process of downgrading a class only when there are multiple subscribers operating under it limits the amount of available resources even though there is room for frequency resources. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first example of an embodiment of the present invention.

FIG. 2 is a diagram illustrating control according to first and second examples of the embodiment of the present invention.

FIG. 3 is a diagram showing a third example of the embodiment of the present invention.

FIG. 4 is a diagram showing control of a third example of the embodiment of the present invention.

FIG. 5 is a diagram showing a fourth example of an embodiment of the present invention.

FIG. 6 is a diagram illustrating control according to fourth and fifth examples of the embodiment of the present invention.

FIG. 7 is a diagram showing a sixth example of the embodiment of the present invention.

FIG. 8 is a diagram illustrating control according to a sixth example of the embodiment of the present invention.

FIG. 9 is a diagram showing a seventh example of the embodiment of the present invention.

FIG. 10 is a diagram illustrating control according to a seventh example of the embodiment of the present invention.

FIG. 11 is a diagram illustrating an example of a conventional priority control method during data transmission.

FIG. 12 is a diagram showing an example of data transmission / reception between a conventional radio base station and a subordinate subscriber station.

[Explanation of symbols]

 000 Wired network 100 Wireless base station 110 Scheduling means 111 Transmission buffer 112 Priority correspondence table 113 Service quality management table 114 Statistical data acquisition means 115 Counter 116 Timer 116 Subscriber station operation status management means 120 Reception processing means 130 Relay processing means 140 Access Control means 150 Lower layer processing means 200-202 Subscriber station

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masataka Iizuka 2-3-1 Otemachi, Chiyoda-ku, Tokyo Within Nippon Telegraph and Telephone Corporation (72) Inventor Masahiro Morikura 2-3-3, Otemachi, Chiyoda-ku, Tokyo No.1 Nippon Telegraph and Telephone Corporation F-term (reference)

Claims (7)

[Claims] 1. A radio base station having a data relay function and a subscriber station for transmitting and receiving data to and from the radio base station, wherein the radio base station operates when data to be relayed arrives. Scheduling means for allocating data to a transmission buffer of a corresponding priority according to the priority information of the data added to the received data, and extracting and transmitting data from the transmission buffer according to a predetermined algorithm. In the scheduling means, there is provided a transmission buffer comprising a plurality of transmission queues having different priorities corresponding to the respective service classes, for providing services of different communication qualities (hereinafter referred to as service classes). A wireless communication system in which the wireless base station transfers data to subordinate subscriber stations while reflecting the priority of data. A base station for wireless packet communication used in a system, wherein a service class for transmitting priority data and a service class for transmitting non-priority data are defined, and a service for transmitting non-priority data is provided. When there is a service class (hereinafter referred to as “best effort class”) for sending normally used best-effort data and a lower service class (hereinafter referred to as “restriction class”) as the class, Means to control the use of low-priority transmission queues to transmit data of the restriction class, correspondence table of transmission queues used when transmitting data in each service class, and transmission of non-priority data Service class management table that manages the service class for each subscriber station, Means for calculating the statistics of the non-priority data for each of the subordinate subscriber stations when the data arrives, a data amount per unit time of the non-priority data arriving at a certain subscriber station (hereinafter referred to as an arrival Means for changing the service class for transmitting non-priority data to the subscriber station to the restricted class when the state in which the rate exceeds the threshold R1 exceeds the time T1. A base station for wireless packet communication. 2. When the radio base station transmits non-priority data to a certain subscriber station, the arrival rate of non-priority data addressed to the subscriber station transmitting data in the restricted class is: Means for changing a service class for transmitting non-priority data to the subscriber station to a best-effort class when it is observed that the state below the threshold value R2 continues for a time T2 or more. Item 2. The base station device for wireless packet communication according to Item 1. 3. A counter is provided in the statistical data acquisition means, and a variable corresponding to each subscriber station under the counter is provided in the counter, and a time interval Ts is used for calculating an arrival rate for each subscriber station. Means for calculating, for each subscriber station, the amount of non-priority data arriving within the time Ts and dividing the amount of non-priority data by the Ts, that is, the average arrival rate within the time interval Ts. When the average arrival rate of the non-priority data to the subscriber station transmitting the non-priority data in the best effort class exceeds the threshold value R1, the variable corresponding to the subscriber station in the counter is set to 1
Otherwise, the variable is set to 0, and when the variable becomes N, that is, when the arrival rate of non-priority data arriving at the subscriber station exceeds the threshold value R1, Time T1 (T1 = N × Ts, N = 1, 2,
Means for changing the service class of the non-priority data to be transmitted to the subscriber station to the restriction class when the continuation is performed, and When transmitting, if the average arrival rate of non-priority data arriving at the subscriber station falls below a threshold value R2, add 1 to the variable, otherwise set it to 0. ,
When the variable reaches M, that is, when the average arrival rate of the non-priority data arriving at the subscriber station is the time T2 (T2 = M × Ts, where M = 1, 2, 3,...) )
3. The wireless packet communication system according to claim 2, further comprising means for changing a service class for transmitting non-priority data to the subscriber station to a best-effort class when the value continuously drops below the threshold value R2. Base station device. 4. A radio base station having a data relay function and a subscriber station for transmitting and receiving data to and from the radio base station, wherein the radio base station operates when data to be relayed arrives. Scheduling means for allocating data to a transmission buffer of a corresponding priority according to the priority information of the data added to the received data, and extracting and transmitting data from the transmission buffer according to a predetermined algorithm. In the scheduling means, there is provided a transmission buffer comprising a plurality of transmission queues having different priorities corresponding to the respective service classes, for providing services of different communication qualities (hereinafter referred to as service classes). A wireless communication system in which the wireless base station transfers data to subordinate subscriber stations while reflecting the priority of data. A base station for wireless packet communication used in a system, wherein a service class for transmitting priority data and a service class for transmitting non-priority data are defined, and a service for transmitting non-priority data is provided. When there is a service class (hereinafter referred to as “best effort class”) for sending normally used best-effort data and a lower service class (hereinafter referred to as “restriction class”) as the class, Means to control the use of low-priority transmission queues to transmit data of the restriction class, correspondence table of transmission queues used when transmitting data in each service class, and transmission of non-priority data Service class management table that manages the service class for each subscriber station, and a non-priority Means for obtaining statistics of data transmitted by a subscriber station (hereinafter referred to as statistical data acquisition means), and a state in which the data transmission speed when data is transmitted to a certain subscriber station in the best effort class exceeds a threshold value R3. Means for changing a service class for transmitting non-priority data to the subscriber station to a restricted class when the time exceeds a time T3. 5. When a radio base station transmits non-priority data to a certain subscriber station, a data transmission rate for a subscriber station transmitting data in a restricted class is lower than a threshold value R4. 5. The wireless packet communication according to claim 4, further comprising means for changing a service class for transmitting non-priority data to the subscriber station to a best-effort class when it is observed that the state continues for a time T4 or longer. Base station equipment. 6. A counter provided inside the statistical data acquisition means, the counter having a variable corresponding to each subscriber station under the counter, and a time interval for calculating a data transmission rate for each subscriber station. Means for calculating the amount of non-priority data transmitted within the time Ts for each Ts, and calculating a value obtained by dividing the amount of the non-priority data by the Ts, that is, an average transmission rate within the time interval Ts, for each subscriber station. When the average transmission rate of the non-priority data transmitted in the best effort class to a certain subscriber station exceeds a threshold value R3, 1 is set to a variable corresponding to the subscriber station in the counter. Add, otherwise set the variable to 0, and when the variable becomes N, that is, when the transmission rate when transmitting non-priority data to the subscriber exceeds the threshold R3 Is the time T3 (T3 = × Ts, N =
Means for changing the service class of the non-priority data to be transmitted to the subscriber station to the restricted class when the above is continuous, and When transmitting non-priority data, if the average transmission rate of non-priority data to the subscriber station falls below a threshold value R4, add 1 to the variable, otherwise set to 0. When the variable reaches M, that is, when the transmission rate of the non-priority data transmitted to the subscriber station is equal to the time T4 (T4 = M
.Times.Ts, where M = 1, 2, 3,...). If the value continuously drops below the threshold value R4, the service class for transmitting non-priority data to the subscriber station is a best-effort class. 6. The wireless packet communication base station device according to claim 5, further comprising: 7. A service class change when transmitting non-priority data to a subordinate subscriber station, comprising a subscriber station operation status management means for managing the operation status of each subordinate subscriber station. 4. A method according to claim 2, further comprising the step of restricting the control of changing the best-effort class to the restricted class in the procedure related to the case where at least K stations among the subordinate subscriber stations are operating. The base station apparatus for wireless packet communication according to any one of claims 5 or 6.