KR20100043968A - Wireless network apparatus having functuin for dynamic trnasmission oppertunity allocating and dynamic trnasmission oppertunity allocating method of wireless network - Google Patents

Abstract

PURPOSE: A wireless network apparatus having function for dynamic transmission opportunity allocating and a dynamic transmission opportunity allocating method of wireless network are provided to improve QoS by assigning a transmission opportunity dynamically according to a kind of data for transmitting the transmission opportunity. CONSTITUTION: A setup unit(110) sets target delay time of transmitted data in a wireless station. A collecting unit(120) calculates an average of packet delay time by gathering packet delay time of transmitted data. A controller(130) assigns transmission opportunity for the data to be transmitted dynamically. The controller controls transmission of the transmission opportunity. A transceiver transmits the transmission opportunity to the wireless station.

Description

WIRELESS NETWORK APPARATUS HAVING FUNCTUIN FOR DYNAMIC TRNASMISSION OPPERTUNITY ALLOCATING AND DYNAMIC TRNASMISSION OPPERTUNITY ALLOCATING METHOD OF WIRELESS NETWORK}

The present invention relates to a wireless network device and a transmission opportunity allocation method of a wireless network, and more particularly, dynamic transmission opportunity allocation that can improve quality of service (QoS) by dynamically allocating transmission opportunities according to the type of data to be transmitted. A wireless network device having a function and a method for allocating dynamic transmission opportunities in a wireless network.

A wireless network is a communication network that can transmit and receive data without a transmission line, and has recently been in the spotlight due to advantages such as mobility and ease of installation.

Conventionally, there are document information or search information using the Internet as a kind of information transmitted from such a wireless network. However, in order to meet the needs of users who require real-time, voice call service and video conferencing service are used in recent wireless networks. And real-time video transmission services.

In order to provide various application services requiring real time as described above, a function capable of enabling quality os service (QoS) is provided or supplemented with a function of a wireless network device.

The above-mentioned wireless network forms a network based on the IEEE 802.11 standard. The existing IEEE 802.11 standard is suitable for data communication and is not suitable for multimedia communication such as voice or video traffic.

The IEEE 802.11e standard is fixed to continuously transmit several frames for a certain time without contention through a hybrid coordination function (HCF), which is a combination of the distributed coordination function (DCF) mode and the point coordination function (PCF) mode in the IEEE 802.11 standard. Quality of Service (QoS) is guaranteed by providing transmission opportunity (TXOP).

 However, the fixed transmission opportunity in the IEEE 802.11e protocol as described above unnecessarily increases or decreases the quality of service due to unnecessarily high or low system resources being allocated to the multimedia traffic, which affects the wireless network system and the multimedia traffic. do.

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide a wireless network apparatus and a wireless network having a dynamic transmission opportunity allocation function capable of improving quality of service (QoS) by dynamically allocating according to the type of data to be transmitted. It is to provide a method for allocating dynamic transmission opportunities in a network.

In order to achieve the above object, one technical aspect of the present invention is a setting unit for setting a target delay time of the data to be transmitted in at least one wireless station, and the packet delay time of the data transmitted in the wireless network network; A collecting unit which collects and calculates an average packet delay time, and a control unit which dynamically allocates a transmission opportunity for transmitting the data according to a comparison result of the target delay time and the average packet delay time, and controls transmission of the transmission opportunity. And a transceiver for transmitting the transmission opportunity to the wireless station under the control of the control unit.

According to one technical aspect of the present invention, the data may include back ground data, best effort data and multimedia data, and the controller may transmit the multimedia data. Opportunities can be allocated dynamically.

According to one technical aspect of the present invention, if the target delay time of the multimedia data is longer than the average packet delay time of the multimedia data, the controller may reduce the time of the transmission opportunity in proportion to a preset unit time, When the target delay time of the multimedia data is shorter than the average packet delay time of the multimedia data, the transmission opportunity time may be increased in proportion to a preset unit time.

According to one technical aspect of the present invention, the multimedia data may be audio data or video data.

According to one technical aspect of the present invention, the multimedia data may include audio data and video data, and the control unit has a target delay time of the audio data and video data, respectively, and average packets of the audio data and video data. If it is longer than the delay time, the transmission time of the audio data and the video data may be reduced in proportion to a preset unit time, and a target delay time of the audio data is longer than an average packet delay time of the audio data and If the target delay time is shorter than the average packet delay time of the video data, the time of transmission opportunity of the audio data may be reduced in proportion to the unit time, and the time of transmission opportunity of video data may be increased in proportion to the unit time. The target delay time of the data is negative If the average packet delay time of the data is shorter and the target delay time of the video data is longer than the average packet delay time of the video data, the time of the transmission opportunity of the audio data is increased in proportion to the unit time and the time of the transmission opportunity of the video data. Can be reduced in proportion to the unit time.

According to one technical aspect of the present invention, the control unit pre-sets the time of transmission opportunity of the audio data if the target delay time of the audio data and the image data is shorter than the average packet delay time of the audio data and the image data, respectively. It is possible to increase in proportion to the set unit time and reduce the time of the transmission opportunity of the image data in proportion to the preset unit time.

According to one technical aspect of the present invention, the controller may assign the transmission opportunity to a preset beacon period.

In order to achieve the above object, another technical aspect of the present invention is to set the target delay time of the data to be transmitted in at least one wireless station, and to collect the packet delay time of the data transmitted in the wireless network network Calculating an average packet delay time, and dynamically allocating a transmission opportunity for transmitting the data according to a result of the comparison between the target delay time and the average packet delay time, and transmitting the transmission opportunity to the wireless station. The present invention provides a method for allocating dynamic transmission opportunities in a wireless network.

According to another technical aspect of the present invention, the data may include back ground data, best effort data and multimedia data, and the transmitting step may include the multimedia data. The transmission opportunity of can be dynamically allocated.

According to another technical aspect of the present invention, the transmitting may reduce the time of the transmission opportunity in proportion to a preset unit time if the target delay time of the multimedia data is longer than the average packet delay time of the multimedia data. If the target delay time of the multimedia data is shorter than the average packet delay time of the multimedia data, the transmission opportunity time may be increased in proportion to a preset unit time.

According to another technical aspect of the present invention, the multimedia data may be audio data or video data.

According to another technical aspect of the present invention, the multimedia data may include audio data and video data, and the transmitting may include setting a target delay time of the audio data and video data, respectively. If the average packet delay time is longer than the transmission time of the audio data and the video data, the time can be reduced in proportion to a preset unit time, and the target delay time of the audio data is longer than the average packet delay time of the audio data and the video If the target delay time of the data is shorter than the average packet delay time of the video data, the time of transmission opportunity of the audio data may be reduced in proportion to the unit time, and the time of transmission opportunity of video data may be increased in proportion to the unit time. The target delay time of the voice data If the average packet delay time of the audio data is shorter and the target delay time of the video data is longer than the average packet delay time of the video data, the time of the transmission opportunity of the audio data is increased in proportion to the unit time and the transmission time of the video data is increased. The time can be reduced in proportion to the unit time.

In the transmitting step, if the target delay time of the audio data and the video data is shorter than the average packet delay time of the audio data and the video data, respectively, the transmission opportunity time of the audio data is increased in proportion to a preset unit time and the video data is increased. A method for allocating a dynamic transmission opportunity in a wireless network, characterized in that to reduce the transmission opportunity time in proportion to a preset unit time.

According to another technical aspect of the present invention, the transmitting step may allocate the transmission opportunity to a preset beacon period.

According to another technical aspect of the present invention, the transmitting step may repeat the collecting step of collecting the average packet delay time after initializing the average packet delay time after allocating the transmission opportunity.

According to the present invention, the quality of service (QoS) can be improved by dynamically allocating a transmission opportunity according to the type of data to be transmitted.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a general wireless network.

Referring to FIG. 1, a general wireless network includes a wireless network device 100 and a plurality of wireless stations 210 to 240.

In a wireless network network conforming to the IEEE 802.11e protocol, the wireless network apparatus 100 allocates a transmission opportunity to allow a plurality of wireless stations 210 to 240 to transmit and receive desired data using limited radio resources.

In this case, the data may be divided into a total of four types of data according to the type of data to be transmitted.

That is, the data may be divided into background data AC0, best effort data AC1, image data AC2, and audio data AC3.

The image data AC2 and the audio data AC3 may be divided into multimedia data.

According to the IEEE 802.11e protocol, the data may have a priority in channel access, and the highest data may be sequentially ordered from the background data AC0 to the best effort data AC1, the image data AC2, and the audio data AC3. May have priority. That is, the background data AC0 may have the lowest priority, and the voice data AC3 may have the highest priority.

In the present invention, a transmission opportunity (TXOP) may be dynamically allocated according to the priority of data.

2 is a block diagram of a wireless network device of the present invention.

Referring to FIG. 2, the wireless network device 100 of the present invention includes a setting unit 110, a collecting unit 120, a control unit 130, and a transceiver unit 140.

The setting unit 110 may set a target delay time of data to be transmitted from the wireless station. Here, the target delay time may be set within 0 to 8160us according to the IEEE 802.11e protocol.

The collector 120 collects an average packet delay time of data being transmitted in a wireless network.

The controller 130 compares the target delay time set by the setting unit 110 with the average packet delay time collected from the collector 120, dynamically sets the transmission opportunity according to the comparison result, and controls the transmission of the transmission opportunity. do.

In this case, the transmission opportunity may be dynamically allocated to only the audio data or the video data among the data according to the priority. For example, if the average packet delay time is longer than the target delay time, the transmission opportunity time is increased and the average is longer than the target delay time. A short packet delay can reduce the time of transmission opportunity.

In the case of dynamically allocating a transmission opportunity to the audio data and the video data among the data, the average packet delay time is longer than the target delay time of the audio data and the average is longer than the target delay time of the video data because the audio data has a higher priority than the video data. If the packet delay time is long, it is desirable to increase the time of transmission of audio data and to reduce the time of transmission of video data.

The transceiver 140 broadcasts the transmission opportunity to the wireless station under control of the controller 130, and transmits the packet delay time of the data being transmitted from the wireless network to the collection unit 120.

The transmission opportunity dynamic allocation of the wireless network device of the present invention described above will be described in more detail.

3 is a flowchart showing a transmission opportunity allocation operation of a wireless network of the present invention.

2 and 3, the wireless network apparatus 100 of the present invention first sets a target delay time of data to be transmitted by at least one wireless station (S11). Next, the packet delay time of the data being transmitted in the wireless network network is collected to calculate the average packet delay time (S12).

Then, if the preset beacon period is not set, the packet delay time is collected and the average packet delay time is calculated. When the preset beacon period is reached (S21), the average packet delay time and the target delay time are compared and transmitted according to the comparison result. The opportunity is changed (S22), and the changed transmission opportunity is broadcasted (S23).

As described above, the change of the transmission opportunity may be applied to the background data, the best effort data, the video data, and the audio data, and may be changed only to the audio data and / or the video data according to the transmission priority.

For example, when the transmission opportunity is changed only for the audio data and the video data, if the target delay time of the audio data and the video data is longer than the average packet delay time of the corresponding data, the time of each transmission opportunity of the audio data and the video data, respectively. By reducing the unit time by a predetermined unit time, the extra radio resource can be used for transmission of background data or best effort data having a low transmission priority.

Further, when the target delay time of one type of data among the audio data and the image data is longer than the average packet delay time of the corresponding data, and the target delay time of the other type of data is shorter than the average packet delay time of the corresponding data, respectively. The time for transmission of data can be reduced or increased.

On the other hand, if the target delay time of the audio data and the video data is shorter than the average packet delay time of the corresponding data, respectively, the time of the transmission opportunity of the audio data is set in advance instead of increasing the time of the transmission opportunity of the audio data and the video data. Increasing the above time, the time of the transmission opportunity of the image data is reduced by a predetermined unit time. This is because the transmission priority of the audio data is higher than that of the video data, so that limited radio resources can be efficiently used.

The unit time used to change the time of the transmission opportunity is a minimum time unit according to the IEEE 802.11e protocol and may be set in multiples of 32usec.

For example, in consideration of the fact that data is transmitted within the transmission opportunity time, if the time is changed when the transmission opportunity time is changed in order to transmit all the data within the transmission opportunity, it may be reduced to the minimum time unit of 32usec. If you increase the time, you can increase it by 64usec or 128usec, which is a multiple of 32usec.

Finally, the packet delay time collected after broadcasting the changed transmission opportunity is initialized (S24). Since the average packet delay time is more meaningful than the past average value, it is preferable to initialize the collected packet delay time and collect the packet delay time again to reflect the latest value (S12). Do.

The wireless network apparatus of the present invention and the communication characteristics by the transmission opportunity dynamic allocation thereof will be described with reference to the drawings.

4 to 6 (a) and (b) are simulations showing communication characteristics of a wireless network by dynamic allocation of transmission opportunities and a wireless network by fixed allocation of transmission opportunities according to the present invention, respectively.

4 to 6 (a) and (b), FIGS. 4 to 6 (a) are simulations based on transmission opportunity dynamic allocation of the present invention, and FIGS. 4 to 6 (b) are transmissions. This is a simulation of assigning opportunities fixedly.

In FIGS. 4A and 4B, traffic of the background data AC0, the best effort data AC1, the video data AC2, and the audio data AC3 is set from 1 Mbps to 20 Mbps. As shown in (a) of FIG. 4, the present invention dynamically allocates a transmission opportunity of voice data AC3. Accordingly, when traffic is 14 Mbps or less, it can be seen that the target delay time is maintained within 20 mses. As shown in (b), in case of fixed allocation of transmission opportunities, packet delay time gradually increases, and data converges according to queue and channel capacity, respectively.

5A and 5B show data throughputs corresponding to FIGS. 4A and 4B, respectively, and are compared with FIG. As the traffic increases, the data throughput is increased by dynamically allocating a transmission opportunity to the voice data AC3.

6 (a) and 6 (b) show that the traffic of voice data AC3 has a fixed value of 2 Mbps and the traffic of background data AC0, best effort data AC1, and video data AC2 has a traffic of 1 to 20 Mbps. Simulation when set to.

As shown in FIG. 6A, when the channel capacity is sufficient as in the dynamic allocation operation described above, the average packet delay time of the video data is 20 msec or less, but when the channel capacity is insufficient, the target of the audio data AC3 is insufficient. It can be seen that the packet delay time of the image data AC2 is increased by increasing the transmission opportunity of the audio data AC3 and maintaining the transmission time of the image data AC2 to maintain the delay time. On the other hand, as shown in (b) of FIG. 6, it can be seen that the image data AC2 increases and converges in packet delay time without a change in transmission opportunity.

As described above, the present invention can vary the transmission opportunity of the data according to the comparison result of the target delay time and the average packet delay time to efficiently use the limited radio resources, and stably transmit the data having high transmission priority. It is possible to improve the quality of service (QoS).

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, but is defined by the claims below, and the configuration of the present invention may be modified in various ways without departing from the technical spirit of the present invention. It will be apparent to those skilled in the art that the present invention may be changed and modified.

1 is a block diagram of a general wireless network.

2 is a block diagram of a wireless network device of the present invention.

3 is a flowchart showing a transmission opportunity allocation operation of a wireless network of the present invention.

4 to 6 (a) and (b) are simulations showing communication characteristics of a wireless network by dynamic allocation of transmission opportunities and a wireless network by fixed allocation of transmission opportunities according to the present invention, respectively.

<Detailed Description of Major Symbols in Drawing>

100 Wireless device 110 Collector

120 ... Setting section 130 ... Control section

140.Transmitter and Receiver

Claims (15)

A setting unit for setting a target delay time of data to be transmitted by at least one wireless station; A collecting unit configured to calculate an average packet delay time by collecting packet delay time of data transmitted in a wireless network; A controller for dynamically allocating a transmission opportunity for transmitting the data according to a result of the comparison between the target delay time and the average packet delay time, and controlling transmission of the transmission opportunity; And A transceiver for transmitting the transmission opportunity to the wireless station under control from the controller A wireless network device having a dynamic transmission opportunity allocation function comprising a. The method of claim 1, The data includes back ground data, best effort data and multimedia data, And the control unit dynamically allocates a transmission opportunity of the multimedia data. The method of claim 2, If the target delay time of the multimedia data is longer than the average packet delay time of the multimedia data, the controller reduces the transmission opportunity time in proportion to a preset unit time, and the target delay time of the multimedia data is the average of the multimedia data. And a shorter packet delay time increases the time of the transmission opportunity in proportion to a preset unit time. The method of claim 3, And the multimedia data is audio data or video data. The method of claim 3, The multimedia data includes audio data and video data, If the target delay time of the audio data and video data is longer than the average packet delay time of the audio data and video data, the controller reduces the time of transmission opportunity of the audio data and video data in proportion to a preset unit time, If the target delay time of the audio data is longer than the average packet delay time of the audio data and the target delay time of the video data is shorter than the average packet delay time of the video data, the time of transmission opportunity of the voice data is proportional to the unit time. Reduce the transmission time of the video data in proportion to the unit time, and the target delay time of the audio data is shorter than the average packet delay time of the audio data, and the target delay time of the video data is the average packet of the video data. If it's longer than the delay And increasing the time of transmission opportunity of the audio data in proportion to the unit time and reducing the time of transmission opportunity of image data in proportion to the unit time. The method of claim 5, If the target delay time of the audio data and the image data is shorter than the average packet delay time of the audio data and the image data, the controller increases the time of transmission opportunity of the audio data in proportion to a preset unit time and A wireless network device having a dynamic transmission opportunity allocation function, characterized in that the time of transmission opportunity is reduced in proportion to a preset unit time. The method of claim 1, And the control unit allocates the transmission opportunity at a preset beacon period. Calculating an average packet delay time by setting a target delay time of data to be transmitted by at least one wireless station, collecting packet delay time of data transmitted in a wireless network; And Dynamically allocating a transmission opportunity for transmitting the data according to a result of comparing the target delay time and the average packet delay time, and transmitting the transmission opportunity to the wireless station. Dynamic transmission opportunity allocation method of a wireless network comprising a. The method of claim 8, The data includes back ground data, best effort data and multimedia data, And wherein said transmitting step dynamically allocates a transmission opportunity of said multimedia data. 10. The method of claim 9, In the transmitting step, if the target delay time of the multimedia data is longer than the average packet delay time of the multimedia data, the transmission opportunity time is reduced in proportion to a preset unit time, and the target delay time of the multimedia data is reduced to And shortening an average packet delay time to increase the transmission opportunity time in proportion to a preset unit time. The method of claim 10, And the multimedia data is voice data or video data. 10. The method of claim 9, The multimedia data includes audio data and video data, In the transmitting step, when the target delay time of the audio data and the video data is longer than the average packet delay time of the audio data and the video data, the transmission time of the audio data and the video data is reduced in proportion to a preset unit time. If the target delay time of the audio data is longer than the average packet delay time of the audio data and the target delay time of the video data is shorter than the average packet delay time of the video data, the time of the transmission opportunity of the voice data is converted into the unit time. Proportionally decrease and increase the time of transmission opportunity of video data in proportion to the unit time, wherein a target delay time of the audio data is shorter than an average packet delay time of the audio data, and a target delay time of the video data is an average of the video data. Longer than packet latency Dynamic transmission opportunity allocation of a wireless network to the time of the transmission opportunity of the time of the transmission opportunity of the audio data the image data to increase in proportion to the unit time, wherein to reduce in proportion to the unit time. The method of claim 12, In the transmitting step, if the target delay time of the audio data and the video data is shorter than the average packet delay time of the audio data and the video data, respectively, the transmission opportunity time of the audio data is increased in proportion to a preset unit time and the video data is increased. A method for allocating a dynamic transmission opportunity in a wireless network, characterized in that to reduce the transmission opportunity time in proportion to a preset unit time. The method of claim 8, And wherein the transmitting step allocates the transmission opportunity at a preset beacon period. The method of claim 14, And the transmitting step repeats the collecting step of collecting the average packet delay time after initializing the average packet delay time after allocating the transmission opportunity.

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