KR20090065168A - Method and apparatus for transmitting/receiving of data with arq in mobile communication system - Google Patents

Abstract

A method and an apparatus for transceiving data are provided to reduce a queuing delay of data by maximizing use of a BSN(Block Sequence Number). A transmitter assigns a BSN to each block(S602). The transmitter transmits 0~9 blocks to a receiver(S604). The receiver generates ACK(Acknowledgement) and NACK(Non-Acknowledgement)(S608,S610). The ACK/NACK is transmitted to the transmitter(S612). The transmitter assigns the BSN to a new SDU(Service Data Unit) block as the number of blocks which receives the ACK(S614). ARQ-TX-NEXT-BSN is updated(S616). The receiver stores the received data block in a DATA Q(S622,S624). The receiver moves the block having the BSN to the DATA Q belonging to a Window range(S626,S628). The ACK/NACK is transmitted to the transmitter(S630,S632). The transmitter transmits the new SDU block including the new BSN(S634).

Description

Method and apparatus for transmitting and receiving data using automatic retransmission request of mobile communication system {Method and Apparatus for Transmitting / Receiving of Data with ARQ in Mobile Communication System}

The present invention relates to a method and apparatus for transmitting and receiving data using an automatic retransmission request of a mobile communication system. Particularly, in the present invention, when there are many service data units (SDUs) to be transmitted, an automatic repeat request (ARQ) in a mobile communication system for maximizing the use of blocks to improve performance is provided. The present invention relates to a method and a transmission and reception apparatus for transmitting and receiving data.

The present invention is derived from the research conducted as part of the information and communication standard development support project of the Ministry of Information and Communication and the Ministry of Information and Telecommunications Research and Development.

In communication systems, various methods are used to prevent the loss or loss of transmitted data. ARQ method is widely used as a representative method among a number of methods for preventing the loss and loss of data.

The ARQ method is a technology for informing the transmitter of unreceived or undecoded data so that the transmitter can retransmit data when the receiver does not receive or decode specific data transmitted by the transmitter.

Since the ARQ method only adds a code for error detection, it is possible to reduce wasted bits for error processing, and many studies have been conducted due to the advantage that the transmitter can perform the operation with only one buffer having a maximum block size. Many kinds of ARQ methods are used in various communication systems.

Meanwhile, in the communication system, various parameters are used to use the ARQ method.

1 is a table for explaining the ARQ parameters used in the portable Internet system.

In the portable Internet system, lost or lost data among transmitted data may be identified and retransmitted using various ARQ parameters illustrated in FIG. 1.

FIG. 2 is a diagram for describing a process of inserting an SDU into an ARQ block in a transmitter.

SDUs delivered from higher layers are divided into block units, and each block is assigned a unique number. The number assigned to each block in this way is referred to as a block sequence number (BSN).

Here, in allocating the BSN to each block, the BSN is sequentially assigned to the SDUs that arrive first. At this time, the first data block to which BSN is first allocated and transmitted through data transmission is called a transmission start data block (ARQ_TX_WINDOW_START, hereinafter referred to as 'ARQ_TX_WINDOW_START'). Typically, the transmission start data block is set to block 0 at the first transmission.

At this time, if the number of blocks of the SDU to be transmitted is smaller than the number of transmission data blocks (ARQ_WINDOW_SIZE, hereinafter referred to as 'ARQ_WINDOW_SIZE'), the BSN is allocated to the blocks of all SDUs. Here, the number of transmission data blocks means the number of data blocks that are set in advance so that they can be transmitted through one data transmission.

When the allocation of the BSN is completed, a transmission unique number (ARQ_TX_NEXT_BSN, hereinafter referred to as 'ARQ_TX_NEXT_BSN') that designates a data block to be transmitted through the next transmission is set to 'last allocated BSN + 1'. Subsequently, the received SDU is allocated from the set value of ARX_TX_NEXT_BSN. At this time, ARQ_TX_NEXT_BSN is updated every time the BSN is allocated.

However, if there are more blocks of SDUs to send than ARQ_WINDOW_SIZE, only BQ is allocated for ARQ_WINDOW_SIZE. When the transmitter checks the ACK message transmitted from the receiver and updates ARQ_TX_WINDOW_START, the transmitter further allocates BSNs as much as the updated number.

As such, the blocks allocated with the BSN are transmitted to the receiver. At this time, the valid period (ARQ_BLOCK_LIFETIME, hereinafter referred to as' ARQ_BLOCK_LIFETIME ') and the elapsed retransmission time (ARQ_RETRY_TIMEOUT, hereinafter referred to as ARQ_RETRY_TIMEOUT') of the data block transmitted when the block is transmitted are set. In addition, when the BSN of the transmitted block is set to the same block as ARQ_TX_WINDOW_START, the sink loss elapsed time ARQ_SYNC_LOSS_TIMEOUT of the transmitted data block is also set.

The receiver identifies the correctly received and unreceived blocks and generates an ACK message to be sent to the transmitter. The receiver transmits the generated ACK message to the transmitter, and the transmitter checks the ACK message to identify a block requiring retransmission, sets ARQ_RETRY_TIMEOUT for the block requiring retransmission, and retransmits it.

In the data transmission process in such a transmitter, there are four types of ACK messages used: Selective ACK, Cumulative ACK, Cumulative with Selective ACK, and Cumulative ACK with Block Sequence ACK.

3A to 3C are diagrams illustrating an operation process of a selective ACK, a cumulative ACK, and a cumulative with selective ACK, and FIG. 3A is a diagram illustrating an operation process of a selective ACK.

The transmitter assigns a BSN to each SDU block to be transmitted, and then transmits the block to which the BSN is assigned to the receiver. The receiver generates an ACK for the received block, generates a NACK for the unreceived block, and transmits it to the transmitter.

The transmitter checks the received ACK / NACK, and retransmits the block in which the NACK is received and the block in which the ACK / NACK is not received within a preset ARQ_RETRY_TIMEOUT time.

ARQ_TX_WINDOW_START is updated when an ACK is received for a block with the same BSN as ARQ_TX_WINDOW_START, or when ARQ_BLOCK_LIFETIME of a block with the same BSN as ARQ_TX_WINDOW_START is exceeded. As shown in FIG. 3A, when block 0 receives a NACK, ARQ_TX_WINDOW_START is not updated.

According to this method, the transmitter and the receiver may identify lost or lost data with respect to the transmitted data by using the selective ACK, and may perform retransmission of the identified lost data or lost data.

3B is a diagram for describing an operation process of a cumulative ACK.

As described with reference to FIGS. 2 and 3A, the transmitter allocates a BSN to each SDU block to be transmitted, and transmits a block to which the BSN is assigned to the receiver.

The receiver generates an ACK and transmits the ACK only to the block (block 3 in FIG. 3B) before the first block not received (block 4 in FIG. 3B).

The transmitter checks the received ACK and retransmits all blocks after the ACK BSN.

Since ACK is received for a block having a BSN equal to ARQ_TX_WINDOW_START, ARQ_TX_WINDOW_START is updated to block 4, and the next block (blocks 10 to 13 in FIG. 3B) is transmitted by the number of updated blocks.

According to this method, the transmitter and the receiver may confirm lost or lost data about the transmitted data by using Cumulative ACK and perform retransmission of the identified lost data or lost data.

3C is a diagram for describing an operation process of cumulative with selective ACK.

As described with reference to FIGS. 2 and 3A, the transmitter allocates a BSN to each SDU block to be transmitted, and transmits a block to which the BSN is assigned to the receiver.

The receiver generates a Cumulative ACK from a block before the block (block 4 in FIG. 3C) that has not been received for the first time (block 3 in FIG. 3C), and generates an ACK / NACK from the next block according to the selective ACK scheme. Transmit to the transmitter.

The transmitter checks the received ACK / NACK, updates ARQ_TX_WINDOW_START to block 4 by Cumulative ACK, and transmits the next block (blocks 10 to 13 in FIG. 3C) as much as updated. Then, the NACK is received by the Selective ACK or a block is not transmitted within the ARQ_RETRY_TIMEOUT time.

According to this method, the transmitter and the receiver may confirm lost or lost data about the transmitted data by using Cumulative with Selective ACK, and may retransmit the identified lost data or lost data.

The currently executed ARQ method differs depending on the above three ACK types, but the size of the BSN that can be used simultaneously for all three ACK types is limited to ARQ_WINDOW_SIZE. In addition, when all ARQ_WINDIOW_SIZE BSNs are in use, if ARQ_TX_WINDOW_START is not updated, a new block cannot be transmitted.

Accordingly, the range of blocks that can be received by the receiver is limited to a reception start data block (ARQ_RX_WINDOW_START, hereinafter referred to as 'ARQ_RX_WINDOW_START') and ARQ_WINDOW_SIZE. Here, ARQ_RX_WINDOW_START represents the first data block received through data transmission.

The last data block received by the receiver is called a reception end data block (ARQ_RX_WINDOW_END, hereinafter referred to as 'ARQ_RX_WINDOW_END'), and ARQ_RX_WINDOW_END is set to 'ARQ_RX_WINDOW_START + ARQ_WINDOW_SIZE-1'.

When using Cumulative ACK, as the ARQ_TX_WINDOW_START is updated, a new BSN can be allocated to a new SDU block and transmitted to the receiver.In a situation where the SDU block to be transmitted is larger than ARQ_WINDOW_SIZE, the ARQ_WINDOW_SIZE BSN is always used. However, since the correctly received blocks must also be retransmitted for blocks after the block receiving the ACK, there is a problem in that resources are wasted.

Selective ACK improves the problem of retransmitting a correctly received block pointed out as a problem of Cumulative ACK, but has a problem that a new block cannot be transmitted unless ARQ_TX_WINDOW_START is updated.

In addition, even if an ACK for the block 0 is received as shown in FIG. 3A, ARQ_TX_WINDOW_START is updated only up to three. Accordingly, unlike the use of BSNs equal to ARQ_WINDOW_SIZE in the Cumulative ACK, two blocks for blocks 6 and 7 that receive the ACK are not used.

Cumulative with Selective ACK can not transmit a new block because ARQ_TX_WINDOW_START is not updated, but has a problem that can not reuse the block as the number of blocks receiving the ACK, such as Selective ACK.

As described above, according to the ACK type selection at the receiver, resource waste due to retransmission of a correctly received block can be solved, but a problem that a block cannot be reused as many as the number of blocks having received an ACK can be solved.

The technical problem to be solved by the present invention is to use ARQ blocks efficiently when there is a lot of data to be transmitted in a mobile communication system, ARQ to solve the problem of resource waste and inefficient use of blocks for retransmission generated in the ARQ transmission process It is to provide a method and a transmitting and receiving device.

To this end, the data transmission method according to the embodiment of the present invention is a data transmission method using an automatic retransmission request, and (a) transmits each data block assigned a unique number by a preset number and transmits the data block to each transmitted data block. Receiving an ACK or NACK for the device; (b) calling a data block corresponding to the number of the received ACK among the data blocks to be transmitted and assigning a unique number; And (c) retransmitting the data block to which the unique number is assigned, the data block to which the NACK is received, and the data block to which the ACK / NACK is not received through step (b), and receiving an ACK or NACK for each of the transmitted data blocks. It includes a step.

In addition, the data receiving method according to an embodiment of the present invention is a data receiving method using an automatic retransmission request, and (a) when a data block assigned a unique number is received, generates an ACK or NACK for each data block. Sending by; (b) receiving a data block to be retransmitted or a data block to which a new unique number is assigned according to the transmission of the ACK or NACK; And (c) generating and transmitting an ACK / NACK for a data block to which a unique number within a preset data receiving range is assigned among the received data blocks.

According to the present invention, when there are a large number of SDU blocks to be transmitted in the mobile communication system, the number of blocks to be transmitted is always maintained by using the BSN such as ARQ_WINDOW_SIZE, thereby maximizing the use of the BSN. Accordingly, the effect of reducing the waiting delay of data, increasing throughput per unit time, and increasing reception probability can be expected.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise. In addition, the terms “… unit”, “… unit”, “module”, etc. described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. have.

Here, in the practice of the present invention, the problem of Cumulative ACK can be solved by using the Selective ACK or Cumulative with Selective ACK, the present invention is not used in Cumulative ACK, the following description to Selective ACK and Cumulative with Selective ACK I will explain only.

4 is a configuration diagram schematically showing the structure of a transmitter and a receiver according to an embodiment of the present invention.

The transmitter 400 according to an embodiment of the present invention includes a reception ACK management module 410, a transmitter timer management module 420, and an ARQ transmission module 430, and the ARQ transmission module 430 includes a transmission control module 432. And transmit unique number processing module 434.

The reception ACK management module 410 performs a function of processing, storing, and managing ACKs and NACKs received from the receiver 440, and updates ARQ_TX_WINDOW_START by calculating the number of blocks that have received the ACK.

The transmitter timer management module 420 performs a timer function of checking a preset time limit for checking whether the ACK / NACK is received.

The transmission control module 432 processes data transmission and reception with the receiver 440 through a mobile communication network. The transmission control module 432 transmits a plurality of SDU blocks to which the BSN is assigned to the receiver 440, and transmits an ACK / It performs the function of checking NACK. Then, the ACK is transmitted to the receiving ACK management module 410 according to the confirmation result of the ACK / NACK, or retransmits the block in which the NACK is received. In addition, according to the update of ARQ_TX_WINDOW_START, the transmission control module 432 allocates as many BSNs as the number of blocks that receive the ACK to the new SDU block.

The transmit unique number processing module (hereinafter referred to as an 'ARQ_TX_NEXT_BSN processing module') 434 is a part for storing and managing a BSN allocated to an SDU block to be transmitted later.

The receiver 440 includes an ARQ reception module 450, a transmission ACK management module 460, a data queue 470 that falls within the Window range, a data queue 480 that does not fall within the Window range, and a receiver timer management module 490. The ARQ receiving module 450 includes a receiving control module 452 and a receiving unique number processing module 454.

The reception control module 452 processes data transmission and reception with the transmitter 400, receives an SDU block transmitted from the transmitter 400, and transmits an ACK / NACK signal generated by the transmission ACK management module 460. Serves to transmit to 400.

A reception unique number processing module (hereinafter referred to as an 'ARQ_RX_HIGHEST_BSN processing module') 454 is a part that processes the BSN according to the SDU block received from the transmitter 400. The ARQ_RX_HIGHEST_BSN processing module 454 stores the value obtained by adding 1 as the BSN of the SDU block having the highest BSN among the SDU blocks received from the transmitter 400.

The transmission ACK management module 460 generates an ACK / NACK according to whether the SDU block is received from the transmitter 400 and transmits the generated ACK / NACK to the transmitter 400 through the reception control module 452. .

The data queue 470 that belongs to the window range is a part that stores the data blocks within the reception range ARQ_RX_WINDOW_START + ARQ_WINDOW_SIZE among the received data blocks, and the data queue 480 that does not belong to the window range includes the received data blocks. This part stores data blocks outside the reception range (ARQ_RX_WINDOW_START + ARQ_WINDOW_SIZE).

The receiver timer management module 490 performs a timer function of checking a preset time limit in order to check whether the SDU block transmitted from the transmitter 400 is received.

5 is a diagram illustrating a signal and an SDU block transmitted and received between a transmitter and a receiver in order to explain the selective ACK according to an embodiment of the present invention.

As described above, a signal between the transmitter 400 and the receiver 440, the SDU block of the transmitter 400, and the SDU block of the receiver may be described, and thus a data transmission / reception process using the selective ACK type may be described.

6 is a flowchart illustrating a data transmission and reception method using a selective ACK type according to an embodiment of the present invention.

Since the number of SDU blocks is larger than ARQ_WINDOW_SIZE, the transmitter 400 allocates BSNs corresponding to ARQ_WINDOW_SIZE to each block. At this time, ARQ_TX_NEXT_BSN becomes 'the last allocated BSN + 1', and becomes block 10 in FIG. 5 (S602).

When the BSN is allocated to each SDU block as described above, an SDU block between ARQ_TX_WINDOW_START and a transmission end data block (ARQ_TX_WINDOW_END, hereinafter referred to as ARQ_TX_WINDOW_END) is transmitted to the receiver 440. Here, ARQ_TX_WINDOW_START is the first data block to which the BSN is allocated, is set to block 0, and ARQ_TX_WINDOW_END is block 9 to be the last data block to which the BSN is allocated. Here, ARQ_TX_WINDOW_END may be calculated as 'ARQ_TX_WINDOW_START + ARQ_WINDOW_SIZE-1'. That is, the transmitter 400 transmits blocks 0 to 9 to the receiver 440 (S604).

The receiver 440 checks the SDU block received from the transmitter 400 (S606). As shown in FIG. 5, the receiver 440 has received block 1, block 2, block 3, block 6, block 7 and block 9, block 0, block 4, and block 5 If block and block 8 are not received, the receiver 440 generates an ACK for the received blocks (block 1, block 2, block 3, block 6, block 7 and block 9). In operation S608, a NACK is generated for the unreceived blocks (blocks 0, 4, 5, and 8) (S610), and the generated ACK / NACK is transmitted to the transmitter 400 (S610). S612).

At this time, the transmitter 400 receives ACKs for blocks 1, 2, 3, 6, and 7, and receives NACKs for blocks 0, 4, and 5, respectively. In one case, the transmitter 400 retransmits the blocks (blocks 0, 4, and 5) where the NACK is received. In addition, the transmitter 400 performs retransmission for blocks (blocks 8 and 9) for which ACK or NACK is not received within a preset ARQ_RETRY_TIMEOUT.

In addition, the transmitter 400 stores the received ACK in the reception ACK management module 410 and then uses it to update ARQ_TX_WINDOW_START.

The transmitter 440 calculates the number of blocks that have received the ACK, allocates BSNs equal to the calculated number of blocks to a new SDU block (S614), and updates ARQ_TX_NEXT_BSN (S616).

In FIG. 5, the number of blocks that receive the ACK is 5, and accordingly, ARQ_TX_NEXT_BSN is updated to block 15. FIG.

Accordingly, blocks 11 to 14 are allocated with a new BSN and are enclosed and transmitted when a block in which NACK is received or a block in which no ACK or NACK is received within ARQ_RETRY_TIMEOUT is retransmitted. At this time, ARQ_RETRY_TIMEOUT and ARQ_BLOCK_LIFETIME are set in blocks 11 to 14 transmitted first (S618).

The receiver 440 receives the retransmitted blocks (blocks 0, 4, 5, 8 and 9) and the first transmitted blocks (blocks 11 to 14) ( S620).

And ARQ_RX_HIGHEST_BSN is set to 'last received BSN + 1'. In FIG. 5, block 15 is set in ARQ_RX_HIGHEST_BSN.

The receiver 440 stores the data block within the reception range ARQ_RX_WINDOW_START + ARQ_WINDOW_SIZE among the received data blocks in the DATA queue 470 belonging to the window range (S622), and receives the reception range ARQ_RX_WINDOW_START among the received data blocks. The data block outside + ARQ_WINDOW_SIZE) is stored in the DATA queue 480 that does not belong to the window range (S624).

The receiver 440 receiving the retransmitted block and the first transmitted block should send an ACK / NACK to the transmitter 400.

However, the receiver 440 according to the present invention is configured not to transmit ACK / NACK for a block stored in the data queue 480 that does not belong to the window range. That is, ACK / NACK is transmitted only for blocks within the range of ARQ_RX_WINDOW_START to ARQ_RX_WINDOW_END, and ACK / NACK is not transmitted for blocks outside the range.

This is because if an ACK / NACK is transmitted for blocks out of range, it may overlap with ARQ_RX_WINDOS_START exceeding ARQ_BSN_MODULUS.

The receiver 440 is newly received from the data queue 480 that does not belong to the window range when ARQ_RX_WINDOW_START is updated due to the reception of block 0 or the data block erase time (ARQ_PURGE_TIMEOUT, hereinafter referred to as 'ARQ_PURGE_TIMEOUT') (S626). The block having the BSN included between the updated ARQ_RX_WINDOW_START and ARQ_RX_WINDOW_END is moved to the DATA queue 470 within the Window range (S628). At this time, ARQ_PURGE_TIMEOUT is set, and an ACK / NACK for blocks stored in the DATA queue 470 belonging to the window range is generated (S630) and transmitted to the transmitter 400 (S632).

The transmitter 400 discards ACK / NACK for blocks outside the range of ARQ_TX_WINDOW_START to ARQ_TX_WINDOW_END. Regarding the ACK / NACK for the block within the range, perform a retransmission of a block in which NACK is received or a block in which no ACK or NACK is received within ARQ_RETRY_TIMEOUT, and allocate a new BSN to a new SDU block by the number of blocks that have received the ACK. Repeat the process to perform (S634).

Blocks outside the range of ARQ_TX_WINDOW_START to ARQ_TX_WINDOW_END do not receive ACK / NACK. Therefore, when ARQ_TX_WINDOW_START is not updated, retransmission is performed whenever ARQ_RETRY_TIMEOUT time is exceeded. According to such a method, the receiver 440 may increase reception rates for the corresponding blocks and may increase the accuracy of data included in the blocks.

FIG. 7 is a diagram illustrating signals and SDU blocks transmitted and received between a transmitter and a receiver in order to explain Cumulative with Selective ACK according to an embodiment of the present invention.

The operation of using Cumulative with Selective ACK according to an embodiment of the present invention is the same as the operation process when using the selective ACK described with reference to FIGS. 5 and 6.

However, after updating ARQ_TX_WINDOW_START for Cumulative ACK, allocating a new BSN to a new SDU block as much as the updated block, there is a difference in performing a selective ACK according to an embodiment of the present invention.

FIG. 8 is a diagram illustrating an operation process when a block 0 is not continuously received in a selective ACK according to an embodiment of the present invention.

FIG. 8 is a diagram illustrating signals and SDU blocks transmitted and received between the transmitter 400 and the receiver 440 when blocks 0 to 9 are not continuously received, and blocks 1 to 9 are received. Here, since block 0 is not received by the receiver 440, ARQ_TX_WINDOW_START and ARQ_RX_WINDOW_START are not updated.

According to an embodiment of the present invention, a new BSN is allocated to blocks 10 to 18 and transmitted. However, since the transmitter 400 does not receive the ACK / NACK for the blocks 10 to 18 from the receiver after transmitting the blocks 10 to 18, the blocks 10 to 10 each time the ARQ_RETRY_TIMEOUT time is exceeded. Block 18 is retransmitted.

8 illustrates a situation in which blocks 10 to 18 are all received through transmission or retransmission before ARQ_TX_WINDOW_START and ARQ_RX_WINDOW_START are updated.

In this case, when block 0 is received by the receiver 440, ARQ_RX_WINDOW_START is updated to block 10, and an ACK of blocks 10 to 18 is transmitted to the transmitter 400. If all the transmitted ACKs are correctly received by the transmitter 400, since ARQ_TX_WINDOW_START is updated to block 19, the block after block 19 changes to the ready state for transmission.

However, in the situation where block 0 is not received, ARQ_TX_WINDOW_START is updated even if the ARQ_BLOCK_LIFETIME time of block 0 is exceeded. In this case, ARQ_TX_WINDOW_START is updated to block 10. Accordingly, the transmitter 400 is changed to the ready state for the transmission of the block 19. As such, ARQ_TX_WINDOW_START of the transmitter 400 is updated, while ARQ_TX_WINDOW_START of the receiver 440 is not updated.

The ARQ_RX_WINDOW_START of the receiver 440 receives the discard message including the delete command for the block 0, or updates the block 10 if the preset ARQ_PURGE_TIMEOUT time is exceeded. In this case, since ARQ_RX_WINDOW_START has been updated, ACK / NACK up to block 10 to block 18 or block 19 is transmitted.

As shown in FIG. 8, in a situation where ARQ_TX_WINDOW_START and ARQ_RX_WINDOW_START are not updated, the transmitter 400 may transmit up to '2' ARQ_WINDOW_SIZE-1 'BSN. In the same manner, the receiver 440 may also receive up to '2 μ ARQ_WINDOW_SIZE-1' BSN.

As described above, according to the embodiment of the present invention, when the number of SDU blocks to be transmitted is larger than ARQ_WINDOW_SIZE, the number of SDU blocks involved in the transmission can always be maintained according to the use of the same BSN as ARQ_WINDOW_SIZE.

The embodiments of the present invention described above are not implemented only through the apparatus and the method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. Implementation may be easily implemented by those skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

1 is a table for explaining the ARQ parameters used in the portable Internet system,

2 is a diagram for explaining a process of assigning an SDU to an ARQ block in a transmitter;

3A to 3C are views illustrating an operation process of a selective ACK, a cumulative ACK, and a cumulative with selective ACK;

4 is a schematic view showing the structure of a transmitter and a receiver according to an embodiment of the present invention;

5 is a view illustrating a signal and an SDU block transmitted and received between a transmitter and a receiver in order to explain the selective ACK according to an embodiment of the present invention;

6 is a flowchart illustrating a data transmission / reception method using a selective ACK type according to an embodiment of the present invention;

7 is a view illustrating a signal and an SDU block transmitted and received between a transmitter and a receiver in order to explain Cumulative with Selective ACK according to an embodiment of the present invention;

FIG. 8 is a diagram illustrating an operation process when a block 0 is not continuously received in a selective ACK according to an embodiment of the present invention.

Claims (9)

In the data transmission method using an automatic retransmission request, (a) transmitting each data block assigned a unique number by a preset number and receiving an ACK or NACK for each of the transmitted data blocks; (b) calling a data block corresponding to the number of the received ACK among the data blocks to be transmitted and assigning a unique number; And (c) retransmitting the data block assigned the unique number, the data block in which the NACK is received, and the data block in which the ACK / NACK is not received through step (b), and an ACK for each of the transmitted data blocks; Receiving NACK Data transmission method comprising a. The method of claim 1, After step (c), In addition, checking whether there is a data block to be transmitted, and if there is a data block to be transmitted, repeatedly performing the process after step (b). The data transmission method further comprising. The method of claim 1, Step (a) is, (a1) dividing the data to be transmitted in units of blocks, and setting the number of previously transmitted data blocks, wherein the number of transmitted data blocks is the number of data blocks that can be transmitted through one data transmission. Assigning each a unique number; (a2) transmitting each data block to which the unique number is assigned a predetermined number; And (a3) receiving an ACK or a NACK for each transmitted data block Data transmission method comprising a. The method of claim 3, Step (a2) is, The transmission start data block set in advance, wherein the transmission start data block is the first data block sent out through the data transmission, and initially set to the 0 block. The transmission end data block is the transmission end data block. Is a last data block to be transmitted and started, and the data block included in 'transmission start data block + number of transmission data blocks-1' is transmitted. The method of claim 4, wherein After step (c), For a specific data block between the transmission start data block and the transmission end data block, if an ACK is received for all data blocks before the specific data block, the transmission start data block and the transmission end data block are reset, respectively. The transmission start data block is reset to the specific data block, and the transmission end data block is reset to the same data block as 'reset transmission start data block + number of transmission data blocks-1' The data transmission method further comprising. The method according to claim 4 or 5, After step (c), And discarding an ACK or a NACK for the data block outside the transmission start data block and the transmission end data block. In a data receiving method using an automatic retransmission request, (a) generating and transmitting an ACK or a NACK for each data block when a data block assigned with a unique number is received; (b) receiving a data block to be retransmitted or a data block to which a new unique number is assigned according to the transmission of the ACK or NACK; And (c) generating and transmitting an ACK / NACK for a data block assigned a unique number within a preset data reception range among the received data blocks; Data receiving method comprising a. The method of claim 7, wherein Step (c) is, Of the received data blocks, a reception start data block, wherein the reception start data block is the first data block received through the data transmission and the reception end data block, wherein the reception end data block is the last received through the data transmission. A data block-generating and transmitting ACK / NACK for data blocks in between. The method of claim 8, Step (c) is, (c1) checking whether all data blocks before a specific data block between the reception start data block and the reception end data block are received; (c2) if all data blocks before the specific data block are received, reset the reception start data block and the reception end data block, respectively, wherein the reception start data block is reset to the specific data block, and the reception end data block is The receiving start data block is changed equally by an amount changed by resetting; And (c3) generating and transmitting ACK / NACK for data between the updated reception start data block and reception end data block; Data receiving method comprising a.

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