KR100582903B1 - Wlan edca mac frame transmission apparatus and method - Google Patents

Abstract

The present invention relates to a WLAN medium access control frame transmission apparatus and method for EDCA support. The apparatus for transmitting a WLAN medium access control frame according to the present invention generates the medium access control frame, classifies the medium access control frame according to user priority information transmitted from an upper logical link control layer unit, and transmits the frame. A WLAN network card controller for storing the classified medium access control frame in a buffer divided into a first buffer area for storing a second buffer area and a second buffer area for storing a next frame to be transmitted, and the media access control frame stored in the buffer. Includes a wifi network card to transmit.

Wlan, frame transmission, wlan network card, wlan network card control unit, queue table

Description

Device and method for transmitting WLAN access frame for WLAN support {WLAN EDCA MAC FRAME TRANSMISSION APPARATUS AND METHOD}

1 illustrates a conventional static buffer operating method.

2 illustrates a conventional dynamic buffer operating method.

3 is a block diagram schematically illustrating an apparatus for transmitting an EDCA support media access control frame according to an embodiment of the present invention.

4 illustrates a transmission queue structure according to an embodiment of the present invention.

5 illustrates a transport frame structure according to an embodiment of the present invention.

6 illustrates a transfer request register according to an embodiment of the present invention.

7 illustrates an interrupt register according to an embodiment of the present invention.

The present invention relates to an apparatus and method for transmitting a WLAN media access control frame for supporting EDCA (Enhanced Distribution Channel Access), and more particularly, to an IEEE 802.11 standard (IEEE Std 802.11e / D5.0) supporting quality of system (QoS). , July 2003, hereinafter referred to as IEEE 802.11e), relates to an apparatus and method for transmitting a WLAN medium access control frame for EDCA support.

Recently, the wireless LAN media access control protocol recommended by the IEEE 802.11 committee is different from the carrier sense multiple access / collision detect (CSMA / CD) scheme used in the wired local area network. Multiple Access / Collision Avoidance) is adopted, and an additional specification is currently recommended to support QoS.

Accordingly, the WLAN medium access control frame is stored in four transmission queues according to user priority information transmitted from a higher layer, and a frame transmission timing and method are applied differently according to internal competition between transmission queues.

In order to transmit such a WLAN medium access control frame, an interface device for transmitting a medium access control frame according to the above-described characteristics between the medium access control layer and the physical layer of the WLAN is required. There are two methods of static buffer and dynamic buffer.

1 illustrates a conventional static buffer operating method.

In the conventional static buffer operating method, a statically allocated buffer for each port is operated. As shown in FIG. 1, a predetermined buffer for each port is allocated to the transmission frame buffer 12, and this is transmitted to the transmission queue table 11. ) Service is performed while rotating by reflecting in order. Since the static buffer operating method allocates each port for each mobile terminal, it is not used in a wireless LAN environment in which a plurality of mobile terminals exist. In addition, the static buffer operation method has a disadvantage in that a number of wasted buffers exist.

2 illustrates a conventional dynamic buffer operating method.

The conventional dynamic buffer operating method is a method of operating a buffer dynamically allocated for each port. As shown in FIG. 2, the buffer is allocated in the order received in the transmission frame buffer 22 and the transmission queue table 21 is used. Save it and send it. This dynamic buffer operation method can reduce the buffer waste, but has a problem that it is difficult to efficiently find a frame for a specific mobile terminal.

In addition, all of the above-described methods store frames in units of MAC Service Data Units (MSDUs), so processing in units of MAC Protocol Data Units (MPDUs) is impossible, and it is impossible to consider mutual conflicts while reducing buffer waste. There was.

The present invention has been proposed to solve the above problems, and an object thereof is to provide an apparatus for transmitting a media access control frame for supporting EDCA satisfying the IEEE 802.11e standard and an operation method thereof.

More specifically, the present invention provides a media access control frame transmission apparatus and an operation method capable of avoiding collision of buffer control between a WLAN network card controller and a WLAN network card while reducing buffer waste.

Another object of the present invention is to provide an apparatus and a method for transmitting a media access control frame capable of processing MPDU units.

In order to achieve the above object, the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, generating the medium access control frame, according to the user priority information transmitted from the upper logical link control layer unit A WLAN network card controller for classifying a medium access control frame and storing the classified medium access control frame in a buffer divided into a first buffer area storing a frame being transmitted and a second buffer area storing a next frame to be transmitted. And a WLAN network card transmitting the media access control frame stored in the buffer.

In the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, the WLAN network card controller is a frame generator for generating the medium access control frame, and the type of the media access control frame to the user priority And classifying according to the transmission frame classifier to transmit to the buffer.

In the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, the medium access control frame is transmitted by a transmission queue, the WLAN network card controller generates a queue table for managing the transmission queue A transmission queue controller, and a transmission buffer controller for controlling the first buffer area.

In the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, the queue table comprises a first queue table for a background service, a second queue table for a best service, and a video service according to an access category. A third queue table, and a fourth queue table for voice service.

In the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, the medium access control frame is stored in a location specified in the corresponding queue table according to the user priority information from the upper logical control layer unit; The transmission time is determined according to internal competition between the transmission queues.

In the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, the transmission queue is a WLAN network card control area that stores whether the medium access control frame validity and transmission failure, the medium access control frame A frame configuration information area for storing information about the configuration of the UE, the last MAC Protocol Data Unit (MPDU) location information area of the MAC Service Data Unit (MSDU), the next transmitted MPDU location information area, and the destination Media Access Control (MAC) address. Area, a transmission vector area, and an area for storing a divided MultiMedia Protocol Data Unit (MMPDU) or MSDU.

In the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, the WLAN network card, a frame transmitter for transmitting the medium access control frame, the medium access control frame transmission request to distinguish the transmission result A transmit request register, an interrupt register for controlling information of the medium access control frame transmit interrupt.

In the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, when the transmission request register requests the medium access control frame transmission to the WLAN network card, the WLAN network card is the requested frame After transmitting all of them, change the setting value of the transmission request register to inform the transmission result.

In the WLAN medium access control frame transmission apparatus according to an aspect of the present invention, the interrupt register includes an interrupt information register for notifying the contents of the interrupt and an interrupt control register for activating or deactivating the interrupt.

According to an aspect of the present invention, a method for transmitting a WLAN medium access control frame includes selecting a frame position that can be stored in a frame buffer with respect to the medium access control frame classified according to user priority information transmitted from an upper logical link control layer unit. Finding and constructing a transmission queue table classified according to the user priority information; Storing the media access control frame in a transmission queue having the frame position; Determining whether to apply an RTS / CTS by referring to frame configuration information stored in the transmission queue; Determining a transmission interval using bit information indicating the start and end of the MSDU; And determining whether to increase the frame position by the slot size or to use the position information of the next MPDU according to whether the frame stores the continuity.

According to another aspect of the present invention, there is provided a method for transmitting a WLAN medium access control frame, comprising: receiving a transmission queue in which the frame is stored; Extracting frame configuration information from the transmission queue and determining whether to apply RTS / CTS; Determining a transmission interval of the frame; Determining how much to increase the frame position according to the continuity of the position at which the frame is stored and whether to use the position information of the next MPDU; Notifying the end of the frame list when the requested frame is transmitted; And if retransmission of the divided frames fails, moving to the start of the next MSDU using the location information of the last MSDU.

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

3 is a block diagram schematically illustrating an apparatus for transmitting a media access control frame for supporting EDCA according to an embodiment of the present invention.

As shown in FIG. 3, the apparatus 2000 for transmitting a media access control frame according to an embodiment of the present invention includes a WLAN network card controller 2100 and a WLAN network card 2200.

The WLAN network card controller 2100 transmits a transmission frame generator 2110 for generating a media access control transmission frame from the upper logical link control layer unit 1000 and a type of a transmission frame from the upper logical link control layer unit 1000. A transmission frame classifier 2120 for classifying according to user priority information to be transmitted to a corresponding queue, a table of a corresponding queue, a transmission queue controller 2130 for controlling a transmission queue storing transmission frames, and controlling transmission queues A transmission buffer controller 2140, a transmission queue table 2150 for managing the transmission queue, and a frame buffer 2160 for temporarily storing the frame.

The transmission queue table 2150 includes four queue tables divided according to access categories, and includes an AC_BK queue table 2151 for a background service, an AC_BE queue table 2152 for a best effort service, AC_VI cue table 2153 for video service and AC_VO cue table 2154 for voice service.

In addition, the WLAN network card 2200 manages information and control of the frame transmitter 2210 responsible for direct frame transmission, a transmission request register 2220 used to distinguish each frame transmission request from a transmission result, and a frame transmission interrupt. And an interrupt register 2230 used for the purpose.

Hereinafter, a method of transmitting a media access control frame for supporting EDCA according to an embodiment of the present invention will be described.

When a transmission frame is generated, the transmission frame generator 2110 generates a media access control frame from the upper logical control layer unit 1000, and the frame classifier 2120 classifies the types of these frames and transmits the transmission queue controller 2130. To send.

The transmission queue controller 2130 finds a frame position FID_PTR in the frame buffer 2160 through which the transmission buffer controller 2140 can store a frame, thereby configuring the transmission queue table. Thereafter, the buffer controller 2140 stores the frame at the found frame position FID_PTR and connects the frame to an existing frame list or constructs a new frame list to be transmitted next. Thereafter, the WLAN network card 2200 finds a frame to transmit and transmits the frame in a timely manner.

4 illustrates a process of storing a transmission frame in the frame buffer 2160 with reference to the transmission queue table 2150.

As shown in FIG. 4, the transmission queue table 2150 includes an index and a frame storage location FID_PTR. The indexes are allocated and managed in ascending order according to the order input to the transmission queue table 2150, and the frame storage location FID_PTR is used to distinguish transmission queues configured by an array of transmission frame structures of the same size.

In addition, the frame buffer 2160 may include a frame buffer area 100 for storing actual frames being transmitted to the WLAN network card 2200 and a frame buffer area 200 for storing frames to be transmitted to the WLAN network card. Include.

Specifically, the frame buffer area 100 includes transmission queues # 11, # 12, # 15, # 21, and # 23 for actually storing one divided frame, and the frame buffer area 200 Transmission queues # 31, # 34, # 35, # 36, and # 39 that store one divided frame to be transmitted next are included.

As such, the frame buffer 2160 is divided into the frame buffer areas 100 and 200 to transmit a frame, thereby causing a collision with the control of the frame buffer 2160 between the WLAN network card controller 2100 and the WLAN network card 2200. Can be avoided. In addition, the reusability of the common frame can be handled in a simple manner.

FIG. 5 shows the internal structure of the transmission queue # 11 shown in FIG.

As shown in FIG. 5, the transmission queue # 11 according to an embodiment of the present invention includes a WLAN network card control area 110, a frame configuration information area 120, and a location information area of the last MPDU of the MSDU. 130), the next transmitted MPDU location information area 140, a receiving MAC address area 150, a transmission vector area 160, a divided Management MAC Protocol Data Unit (MMPDU) or a MAC Service Data Unit (MSDU) area ( 170).

The WLAN network card control area 110 includes a 'V (valid)' indicating validity of a frame and a 'transmit error' (TE) indicating a frame transmission failure. 120 shows an 'RC bit (RTS / CTS)' indicating whether or not to transmit the RTS / CTS mechanism, a 'LE bit' indicating the end of the frame list, and a 'ME bit' indicating the end of the MSDU. It includes a 'MB bit (MSDU Begin)' indicating the start of the MSDU, and 'CE bit (Chunk End)' indicating the discontinuity of the region in which the frame is stored.

According to an embodiment of the present invention, the transmission queue # 11 includes a WLAN network card control area 110 so that the WLAN network card 2200 can reflect the frame transmission result, and the WLAN network card ( 2200 includes frame information control regions 120-160 so that the frame can be efficiently transmitted, and finally includes the actual frame region 170.

Hereinafter, a process of transmitting a frame in the transmission queue # 11 will be described.

The WLAN network card controller 2100 notifies the WLAN network card 2200 of the frame transmission using the transmission request register 2220 when the frame is ready for transmission. After receiving the transmission queue # 11, the wireless network card 2200 determines whether to apply the RTS / CTS with reference to the frame configuration information area 120 of the transmission queue # 11, and determines the start and end of the MSDU. The notifying bit information is used to determine the transmission interval. In addition, it is determined whether to increase the frame position by the slot size or to use the position information of the next MPDU according to the continuity of the position where the frame is stored.

In addition, when the end of the frame list is transmitted, the interrupt register 2230 notifies the fact that the requested frame is transmitted.

When retransmission of the divided frames fails, the position information 130 of the last MPDU indicating the end of the last MSDU is used to move quickly to the start of the next MSDU. By doing in this way, transmission performance can be improved rather than continuing to move the several positional information of a divided frame.

Lastly, when the RTS / CTS mechanism is to be used, the MAC address information area 150 is used to reduce the trouble of analyzing the MAC address in the area 170 where the actual frame is stored. Is transmitted using the transmission vector information region 160.

6 illustrates a transmit request register 2220 in accordance with the present invention.

As illustrated in FIG. 6, the transmission request register 2200 includes an AC_BK_TRQ register 2221 indicating a transmission request of a frame corresponding to a background service, an AC_BE_TRQ register 2222 indicating a transmission request of a frame corresponding to a best service, and an image. An AC_VI_TRQ register 2223 indicating a request for transmission of a frame corresponding to a service, and an AC_VO_TRQ register 2224 indicating a request for transmission of a frame corresponding to a voice service.

That is, when the transmission request register 2220 sets the register value to '1' to notify the WLAN network card 2200 of the transmission request, the WLAN network card 2200 transmits the requested frame and then sets the register value to '1'. Set to 0 'to inform the transmission result.

7 illustrates an interrupt register 2230 in accordance with one embodiment of the present invention.

As shown in FIG. 7, the interrupt register 2230 includes an interrupt information register 2231 used to inform the contents of an interrupt and an interrupt control register 2232 used to activate or deactivate an interrupt.

That is, after setting a specific bit of the interrupt information register 2231 to '1' and notifying the interrupt using the interrupt control register 2232, the corresponding interrupt can be processed.

In the above, the apparatus and method for transmitting WLAN access frame according to an embodiment of the present invention have been described. The embodiment described above is an embodiment to which the concept of the present invention is applied, and the scope of the present invention is not limited to the above embodiment, and various modified embodiments may be configured using the concept of the present invention as it is.

According to the present invention, by designing a buffer and queue structure for transmitting a WLAN medium access control frame for EDCA support based on user priority information provided by a higher layer, EDCA support that satisfies the IEEE 802.11e standard is supported. A media access control frame transmission apparatus and a method of operating the same can be provided.

More specifically, it is possible to provide a media access control frame transmission apparatus and an operation method capable of avoiding collision of buffer control between a WLAN network card controller and a WLAN network card while reducing buffer waste.

In addition, the present invention can provide a media access control frame transmission apparatus and an operation method capable of processing MPDU units.

Claims (14)

In the WLAN medium access control frame transmission apparatus, The media access control frame is generated, the media access control frame is classified according to user priority information transmitted from an upper logical link control layer, and a first buffer area for storing a frame being transmitted and a frame to be transmitted next are stored. A WLAN network card controller for storing the classified medium access control frame in a buffer divided into a second buffer area; And WLAN network card transmitting the media access control frame stored in the buffer WLAN medium access control frame transmission apparatus comprising a. The method of claim 1, The WLAN network card controller includes a frame generator for generating the media access control frame, and a transmission frame classifier for classifying the type of the media access control frame according to the user priority and transmitting the classified frame type to the buffer. Control frame transmission device. The method of claim 2, The medium access control frame is transmitted by a transmission queue, The WLAN network card controller further comprises a transmission queue controller for generating a queue table for managing the transmission queue, and a transmission buffer controller for controlling the first buffer area. The method of claim 3, The queue table includes a first queue table for a background service, a second queue table for a best service, a third queue table for a video service, and a fourth queue table for a voice service according to an access category. Access control frame transmission device. The method of claim 4, wherein The medium access control frame is stored at a location specified in a corresponding queue table according to user priority information from the upper logical control layer unit, and the transmission time of the WLAN medium is determined according to internal competition between the transmission queues. Frame transmission device. The method of claim 3, The transmission queue is, A wireless LAN network card control area storing validity of the medium access control frame and transmission failure; A frame configuration information area for storing information on the configuration of the medium access control frame; Last MAC Protocol Data Unit (MPDU) location information area of the MAC Service Data Unit (MSDU), MPDU location information area sent next, The receiving Media Access Control (MAC) address area, Transmission vector region, and An apparatus for transmitting a WLAN media access control frame including an area for storing a divided MMPDU or an MSDU. The method of claim 1, The wifi network card, A frame transmitter for transmitting the medium access control frame, A transmission request register for distinguishing the medium access control frame transmission request from the transmission result, and And a interrupt register for controlling information of the medium access control frame transmission interrupt. The method of claim 7, wherein When the transmission request register requests the WLAN network card to transmit the medium access control frame, the WLAN network card transmits all of the requested frames and then changes a setting value of the transmission request register to thereby transmit a result. Informing WiFi medium access control frame transmission device. The method of claim 7, wherein The interrupt register includes an interrupt information register for notifying the contents of the interrupt and an interrupt control register for activating or deactivating the interrupt. In the WLAN medium access control frame transmission method, Configuring a transmission queue table classified according to the user priority information by finding a frame position that can be stored in a frame buffer for the medium access control frame classified according to user priority information transmitted from an upper logical link control layer unit ; Storing the media access control frame in a transmission queue having the frame position; Determining whether to apply an RTS / CTS by referring to frame configuration information stored in the transmission queue; Determining a transmission interval using bit information indicating the start and end of the MSDU; And Determining whether to increase the frame position by the slot size according to the continuity of the position in which the frame is stored and whether to use the position information of the next MPDU. WLAN medium access control frame transmission method comprising a. delete delete The method of claim 10, When transmitting the frame, when transmitting the end of the frame list, the WLAN medium access control frame transmission method for transmitting the transmission result of the frame. In the WLAN medium access control frame transmission method generated by a WLAN network card controller, Receiving a transmission queue in which the frame is stored; Extracting frame configuration information from the transmission queue and determining whether to apply RTS / CTS; Determining a transmission interval of the frame; Determining how much to increase the frame position according to the continuity of the position at which the frame is stored and whether to use the position information of the next MPDU; Notifying the end of the frame list when the requested frame is transmitted; And If retransmission of the divided frames fails, using the position information of the last MSDU to move to the beginning of the next MSDU WLAN medium access control frame transmission method comprising a.

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