KR101118689B1 - Apparatus and method for transmitting and receiving data frame which is applied advanced coding - Google Patents

Abstract

An apparatus and method for transmitting and receiving a data frame to which advanced coding is applied are provided. The apparatus for transmitting / receiving the data frame to which the advanced coding is applied may include a setting unit for setting the use of advanced coding in the data frame, a control unit for searching and determining the contents set in the data frame, and a data frame according to the contents set in the data frame. And a processing unit for processing and a transmission / reception unit for transmitting and receiving data frames, wherein the advanced coding is an error correction algorithm.

WLAN, Advanced Coding, ACK

Description

Apparatus and method for transmitting and receiving data frame which is applied advanced coding}

1 illustrates a configuration of a data frame transmitted and received between conventional WLAN devices.

2 is a block diagram of an apparatus for transmitting and receiving a data frame to which advanced coding is applied according to an embodiment of the present invention.

3 is a flowchart of processing a data frame to which advanced coding is applied according to an embodiment of the present invention.

4 illustrates a data frame when using a delay short interframe space (DSIFS) according to an embodiment of the present invention.

5 illustrates a data frame when using a delay block response according to an embodiment of the present invention.

6 illustrates a data frame when no delay block response is used according to an embodiment of the present invention.

<Explanation of symbols on main parts of the drawings>

10: transmitting side 20: receiving side

30: short interframe space

33: delay short interframe space

100: setting unit 105: control unit

110: processor 120: transceiver

306a: Advanced coding enabled field

306b: delay response field

308a: duration field

308b: Control field of quality of service

402: block response request frame

404: block response frame

The present invention relates to an apparatus and method for transmitting and receiving data frames to which advanced coding is applied, and more particularly, to an apparatus and method for transmitting and receiving data frames for performing stable data processing while adding an advanced coding function.

Recently, with the proliferation and development of digital products, digital technology requires the development of high-speed wireless LAN. In addition, there is an increasing demand for user data quality, particularly audio and video data. In a WLAN environment, stable transmission may be difficult due to the inherent characteristics of the radio (multipath, fading, etc.).

1 illustrates a configuration of a data frame transmitted and received between conventional WLAN devices.

When the transmitting side 10 transmits the data frame to the receiving side 20, the MAC (Medium Access Control) and the PHY (Physical) layer of the data frame each form a header and add data thereto. send. The receiving side 20 which receives the data may detect whether an error occurs in the data frame through a frame check sequence (FCS). If there is no error, the receiving side 20 transfers the data frame to a higher layer and processes it.

In addition, the short interframe space (SIFS) 30 of the 802.11 protocol ensures a minimum interval between frames. This interval includes the delay time of the PHY, the time of processing the frame of the MAC, and the RxTx turnaround time (Receive or Receiver / Transmit or Transmitter Turnaround Time). That is, it may be referred to as a time when the receiver 20 receives a data frame, processes the data frame, and prepares to transmit an acknowledgment (ACK) frame. For example, the short interframe space 30 of the 802.11a specification is defined as 16usec.

However, when the advanced coding technique is used, the time for decoding the data at the receiver 20 becomes longer. According to the 802.11a PHY standard, the time interval of the short interframe space 30 includes a Receive or Receiver Radio Frequency (RxRF) delay, a Receive or Receiver Physical Layer Convergence Protocol (RxPLCP) delay, a MAC processing delay, and an RxTx turnaround time. It is composed of the sum of the times. In this case, the RxPLCP delay time and the MAC processing time are less than 2usec, respectively, and other values may vary depending on the implementation.

Meanwhile, in order to solve a problem in which transmission quality is degraded and transmission is interrupted due to instability of a channel environment in a WLAN environment, an advanced coding function such as forward error correction (FEC) has been added to the PHY. Therefore, there is a problem in that the timing portion of the 802.11a standard cannot be satisfied. That is, when using a technique such as Low Density Parity Check (LDPC), Reed Solomon (RS) and Interleaver (Interleaver) in processing data (including decoding) at the receiving side 20 PHY, short interframe of 802.11a There is a problem that it is difficult to decode in the space 30.

Therefore, there is a need to provide a stable and improved data service to a user by applying advanced coding to data and solving the problem of data processing time accordingly.

An object of the present invention is to provide an apparatus and method for transmitting and receiving data frames to which advanced coding is applied.

The objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the apparatus for transmitting / receiving a data frame to which advanced coding is applied according to an embodiment of the present invention searches for and determines a setting unit for setting whether or not to use advanced coding in a data frame and contents set in the data frame. And a control unit for processing the data frame and a transceiver for transmitting / receiving the data frame according to contents set in the data frame, wherein the advanced coding is an error correction algorithm.

The method of transmitting / receiving a data frame to which advanced coding is applied includes setting the use of advanced coding in a data frame, retrieving and determining the contents set in the data frame, and processing the data frame according to the contents set in the data frame. And the step of transmitting and receiving data frames, wherein the advanced coding is an error correction algorithm, and when the delayed short interframe space is set to use, the time of the delayed short interframe space is encoded in the encoded data frame according to the advanced coding. And decoding for a predetermined time including an interval.

Specific details of other embodiments are included in the detailed description and the drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and only the embodiments make the disclosure of the present invention complete, and the general knowledge in the art to which the present invention belongs. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

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

2 is a block diagram of an apparatus for transmitting and receiving a data frame to which advanced coding is applied according to an embodiment of the present invention.

The data frame transmission / reception apparatus to which the advanced coding is applied includes a setting unit 100, a control unit 105, a processing unit 110, and a transmission / reception unit 120.

The setting unit 100 sets whether or not advanced coding is used in a predetermined portion of the data frame of the transmitting side 10. Preferably, it can be divided into a case of having a value of 1 (if data is encoded) and a case of having a value of 0 (zero) (not encoding data). The receiving side 20 determines whether the data of the transmitting side 10 has been encoded by advanced coding through the set part, and decodes the encoded data accordingly. In this case, the advanced coding refers to an algorithm related to error correction (FEC), and the advanced coding may be implemented in the MAC layer which is the PHY layer or higher layer of the data frame.

In addition, in consideration of the delay problem of the data processing time of the existing receiving side 20, it is set whether or not to use the delayed short interframe space 33 instead of the short interframe space 30. When the delayed short interframe space 33 (DSIFS) is used, the data frame is more accurately processed by solving the delay time caused by the data processing of the existing receiver 20. More specific details will be described later in FIG. 4 and will be omitted below.

In addition, it is set whether or not to use a delayed block response according to the policy of the block response 404 of the data frame. The configuration of the data frame according to the use of the delay block response will be described with reference to FIGS. 5 and 6 and will be omitted below.

The controller 105 searches and determines whether the advanced coding is used, whether the delay short interframe space is used, and whether the delay block response is used according to the value set through the setting unit 100.

The processing unit 110 processes the data according to the setting contents of the setting unit 100 retrieved by the control unit 105. For example, when the receiving side 20 determines through the setting of the setting unit 100 that the data of the transmitting side 10 is advanced encoded, the receiving side 20 decodes the data encoded by the advanced coding. . At this time, the receiving side 20 may perform decoding during the time of the duration field 308a of the transmitting side 10 to be described later depending on whether the delay short interframe space 33 is used. More specific details will be described later with reference to FIG. 4.

In addition, depending on whether the delay block response set in the setting unit 100 is used, the receiving side 20 may determine whether to transmit a response frame to the transmitting side 10. Data processing and frame configuration according to the use of the delay block response will be described later with reference to FIGS. 5 and 6.

The transceiver 120 transmits and receives a data frame between the transmitter 10 and the receiver 20.

3 is a flowchart of processing a data frame to which advanced coding is applied according to an embodiment of the present invention.

The use of advanced coding in the data frame is set through the setting unit 100 (S310).

In addition, at least one of the setting of the use of the delay short interframe space and the use of the delay block response is set through the setting unit 100 (S320).

The above steps may be in a different order.

The value set in the data frame is searched and determined through the control unit 105, and the data is processed through the processing unit 110 according to the set value (S330, S340).

Detailed description of the operation of each configuration will be omitted with reference to FIGS. 4, 5 and 6 below.

The data processed through the transceiver 120 is transmitted (S350).

4 illustrates a data frame when using a delay short interframe space (DSIFS) according to an embodiment of the present invention.

When the advanced encoding is applied to improve the service quality in the WLAN, the configuration of the data frame and the operations of the transmitting side 10 and the receiving side 20 in a single frame will be described.

The preamble field 302 is a portion of an 802.11 High Throughput Physical Layer Protocol Data Unit (PPDU) used for PHY synchronization and channel estimation.

The legacy signal (LS) field 304 includes length and rate information (ie, reception time information), and the receiving side 20 receives a data frame during the corresponding reception time through the information. .

A high throughput signal (HTS) field 306 includes an advanced coding usage field 306a and a delay response field 306b. In the advanced coding use field 306a, whether or not advanced coding is used is set to inform the receiving party 20 whether data of the transmitting side 10 has been encoded according to the advanced coding. The delay response field 306b is set with data for notifying the receiving side 20 of the use of the delay short interframe space 33 of the transmitting side 10.

The MAC header field 308 includes a duration field 308a, and the time taken to decode at the receiving side 20 is set in the duration field 308a. The transmitting side 10 decodes the duration field 308a in the MAC header field 308 of the transmitting data frame at the receiving side 20 instead of the sum of the time interval and response time of the short interframe space 30. The time value obtained by adding the time interval and response time of the delayed short interframe space 33 considering the time taken may be transmitted. At this time, the delay short interframe space 33 may be preferably greater than 16usec. In this case, the delay response field 306b indicates that the delay short interframe space 33 is using the delay short interframe space 33. ), A predetermined value (for example, a value of 1) is set.

The receiving side 20 PHY performs decoding for the delay short interframe space 33 time, processes the received frame, and transmits a response frame. The transmitting side 10 waits for a time interval that is the sum of the time interval of the delayed short interframe space 33 and the response time set and transmitted by itself, and there is no transmission of the response frame of the receiving side 20 during this time. If it is, the transmission is regarded as a failure and an attempt is made to retransmit the data frame. The remaining 802.11a compliant WLAN devices sleep the Network Allocation Vector (NAV) for the time interval of the delayed short interframe space 33 and the response time, so that the devices with this configuration are installed. No conflict

In this way, the advanced coding is applied to the data frame and the delay short interframe space 33 is used to ensure stable and accurate data processing. Hereinafter, the case of multi-frame will be described in FIG. 5.

5 illustrates a data frame when using a delay block response according to an embodiment of the present invention.

FIG. 5 may include fields included in the data frame of FIG. 4, and different contents from the fields described in FIG. 4 will be mainly described, and overlapping portions will be omitted.

5 (a) is a case in which the block response frame 404 can be directly transmitted, and the receiving side 20 can transmit the block response frame 404 subsequent to the response frame. This is a case where a transmission acceptance (CF-Poll; Contention Free Poll) 406 is received from an access point (AP) and transmitted. Hereinafter, each element of the data frame and operations of the transmitting side 10 and the receiving side 20 will be described.

The duration field 308a of the MAC header field 308 is the time it takes the receiver 20 to process the data. Preferably, the receiver 20 transmits a response frame and then continues to the block response frame 404. It is set to the time of.

The control field 308b of the quality of service includes policy information regarding the block response frame 404. That is, it includes a setting value for the use of the delay block response, and when the delay block response is used, the receiving side 20 transmits the response frame to the transmitting side 10 when receiving the data frame, and then the block response frame ( 404). 6, which will be described later, does not use a delayed block response, and the receiving side 20 does not send a response frame for data frame reception within a section to which the block response frame 404 is applied. Therefore, the receiving side 20 responds to the block response request frame 402 of the transmitting side 10 as a response frame, and then generates a block response frame 404 and transmits it to the transmitting side 10.

In addition, the transmitting side 10 transmits a data frame that does not apply advanced encoding to the request frame at the time when the block response request frame 402 corresponding to the control frame should be transmitted while the data frame is being transmitted, thereby shortening the data. The problem of the timing violation of the interframe space 30 (SIFS) may be solved. That is, the data transmission uses advanced encoding while the block response request frame 402 which is a control frame does not apply advanced encoding, thereby ensuring stability for the data transmission interval. In this case, if the advanced encoding is applied to the data, the advanced coding use field 306a is set to 1, and for the block response request frame 402 without the advanced encoding, the advanced coding use field 306a The value can be set to zero.

Also, instead of performing advanced encoding on control frames such as the block response request frame 402 and the block response frame 404, error correction is made by reducing the transmission rate by sufficiently lowering the transmission rate. Will replace (FEC). In this case, preferably, the block response frame 404 mechanism introduced in 802.11e may be used.

6 illustrates a data frame when no delay block response is used according to an embodiment of the present invention.

FIG. 6 may include fields included in the data frames of FIGS. 4 and 5, and has a similar operation principle to that of FIG. 5, but FIG. 5 shows that the sender 10 is responsible for the block response request frame 402. While receiving the response frame and subsequently receiving the block response frame 404, FIG. 6 shows that the sender 10 skips the response frame to the block response request frame 402 and immediately replaces the block response frame frame 404. Receive. That is, the receiving side 20 does not send a response frame to the reception of the data frame in the section to which the block response frame 404 is applied. At this time, the control field 308b of the quality of service may be set to a predetermined value (for example, a zero value) such that the delay block response is not used according to the policy information regarding the block response frame 404. have.

The sender 10 sets up 500 an adblock as shown in FIG. 6 (b) to immediately omit the response frame to the block response request frame 402 and to receive the block response frame 404. Through the use field 502a of the ad block, the transmitting side 10 and the receiving side 20 may determine whether to use the block response frame 404 in which the response frame is omitted. The transmitting side 10 and the receiving side 20 negotiate a block response session through transmission and reception of request and response 504 frames of the ad block, and preferably a procedure described in 802.11e. Follow.

In this way, the transmitting side 10 and the receiving side 20 can receive a simple and stable traffic by receiving the block response frame 404 immediately without the procedure of the response frame.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

According to the apparatus for transmitting and receiving a data frame to which the advanced coding of the present invention as described above has one or more of the following effects.

First, there is an advantage of ensuring stable data transmission between wireless devices.

Second, there is an advantage of reducing data retransmission through error correction between wireless devices.

Third, advanced coding can be implemented in PHY and MAC without violating existing data processing time.

Claims (5)

Setting whether to use advanced coding in a data frame, and setting at least one of use of a delayed short interframe space and use of a delayed block ACK in the data frame. part; A controller for searching and determining contents set in the data frame; A processor configured to process the data frame according to contents set in the data frame; And And a transceiver for transmitting and receiving the data frame, wherein the advanced coding is an error correction algorithm. The method of claim 1, The setting unit transmits and receives a data frame to which advanced coding is applied, characterized in that the transmission rate is lowered without encoding according to the advanced coding when the control frame is transmitted. 3. The method of claim 2, And the processing unit decodes the data frame encoded according to the advanced coding for a predetermined time including a time interval of the delay short interframe space when the delay short interframe space is set to use. Transmitter and receiver of data frame to which coding is applied. Setting the use of advanced coding in a data frame; Searching for and determining contents set in the data frame; Processing the data frame according to contents set in the data frame; and And transmitting and receiving the data frame, wherein the advanced coding is an error correction algorithm, and when the delay short interframe space is set to use, the data frame encoded according to the advanced coding the delay short interframe space. A method of transmitting and receiving a data frame to which advanced coding is applied, wherein the decoding is performed for a predetermined time including a time interval. The method of claim 4, wherein And setting at least one of a setting for the use of the delayed short interframe space and a use of the delay block response to the data frame, wherein the control frame is not encoded according to the advanced coding. A method of transmitting and receiving a data frame to which advanced coding is applied, wherein the transmission rate is lowered.

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