KR20090116614A - Apparatus and method for processiing radio link control data in mobile telecommunication system - Google Patents

Abstract

PURPOSE: A radio link control data processing apparatus in a mobile communication system and a method thereof are provided to prevent a STATUS REPORT transmission triggered by a polling PDU from being delayed by a STATUS REPORT prohibit timer. CONSTITUTION: It is determined whether an RLC status report which includes states of received RLC packet data units is triggered(305). If so, it is determined whether an RLC status report prohibit timer for prohibiting the RLC status report for a predetermined time is being driven(310). If so, a cause which makes the RLC status report triggered is checked(320). If the RLC status report is triggered by the polling PDU, the RLC status report is transmitted(315).

Description

APPARATUS AND METHOD FOR PROCESSIING RADIO LINK CONTROL DATA IN MOBILE TELECOMMUNICATION SYSTEM

The present invention relates to an RLC data processing apparatus and method of a radio link control (RLC) layer in a mobile communication system.

UMTS (Universal Mobile Telecommunication Service) system is based on the European mobile communication system Global System for Mobile Communications (GSM) and General Packet Radio Services (GPRS), and Wideband Code Division Multiple Access, Third generation asynchronous mobile communication system using " CDMA. &Quot;

The 3rd Generation Partnership Project (3GPP), which is in charge of UMTS standardization, is discussing the Long Term Evolution (LTE) as the next generation mobile communication system of the UMTS system.

The LTE system is a technology for implementing high-speed packet-based communication having a transmission rate of up to about 100 Mbps, and aims to commercialize it in 2010. In particular, various communication schemes for LTE systems have been proposed. For example, there is a scheme for reducing the number of nodes located on a communication path by simplifying a network structure, and schemes for bringing wireless protocols as close to a wireless channel as possible. That's an example.

1 illustrates an example of a next generation mobile communication system to which the present invention is applied.

Referring to FIG. 1, next-generation radio access networks (hereinafter referred to as' E-RAN's) 110 and 112 are next-generation base stations (hereinafter referred to as' Evolved Node B '(hereinafter referred to as' ENB or Node B')) 120, 122, 124, 126, and 128, and next-generation GGSN (Gateway GPRN Support Node (EGGSN, hereinafter referred to as 'Access Gateway') 130, 132, which is an upper node, is simplified to a two-node structure. Equipment (hereinafter referred to as 'UE') 101 is connected to the Internet Protocol (hereinafter referred to as 'IP') network 114 by the E-RANs 110 and 112.

The ENBs 120 to 128 correspond to existing Node Bs of the UMTS system and are connected to the UE 101 by a radio channel. Unlike the existing Node B, the ENBs 120 to 128 play a more complex role. In the LTE system, all user traffic including real-time services such as Voice over IP (VoIP) through the Internet protocol is serviced through a shared channel, so a device for collecting and scheduling situation information of UEs is needed. 120 to 128 are in charge of this.

In order to realize a transmission rate of up to 100 Mbps, an LTE system uses orthogonal frequency division multiplexing (OFDM) as a wireless access technology in a bandwidth of up to 20 MHz. In addition, an adaptive modulation & coding (AMC) scheme that determines a modulation scheme and a channel coding rate according to the channel state of the terminal is applied.

In this regard, there is a need for a concrete plan on how to process data in relation to packet data in a next generation mobile communication system.

The present invention provides an apparatus and method for processing a status report in a radio link control (RLC) device in a mobile communication system.

The present invention also provides an apparatus and method for processing a status report with respect to retransmission data in an RLC device in a mobile communication system.

The present invention also provides an apparatus and method for processing polling data in an RLC apparatus in a mobile communication system.

The present invention also provides an apparatus and method for controlling the transmission of an unnecessary status report between an RLC transmitting apparatus and an RLC receiving apparatus in a mobile communication system.

The present invention also provides an apparatus and method for controlling retransmission of unnecessary polling data between an RLC transmitting apparatus and an RLC receiving apparatus in a mobile communication system.

In the mobile communication system according to the present invention, a radio link control (RLC) data processing method, a radio link control (RLC) data processing method in a mobile communication system, the status of the received packet data units (PDU) Checking whether an RLC status report for acquiring an RLC status report has been triggered; and checking whether an RLC status report prohibit timer for prohibiting the RLC status report for a predetermined time is running, if the RLC status report is triggered; If the RLC status report prohibit timer is running, checking the cause of the RLC status report triggering; and if the RLC status report is triggered due to the check result and the polling PDU, transmitting the RLC status report. It includes.

In the mobile communication system according to the present invention, a method for processing radio link control (RLC) data includes a first timer, which is a time when an unreceived RLC packet data unit (PDU) is delayed due to HARQ processing. T_reordering timer) expires, triggering a RLC STATUS REPORT that receives the status for the received PDUs, and if the RLC status report is triggered, the RLC status prohibits the RLC status report for a predetermined time. Checking whether a reporting prohibit timer is running, checking if there is a polling PDU whose order reordering has not yet been completed, if the prohibiting timer is not running, and if the polling PDU exists, Canceling generation of the RLC status report triggered by the controller; and generating and transmitting the RLC status report if the polling PDU does not exist. It includes the process.

In the mobile communication system according to the present invention, a radio link control (RLC) data processing apparatus checks whether an RLC status report (RLC STATUS REPORT) containing a status for received packet data units (PDUs) has been triggered, and If the RLC status report is triggered, it is checked whether the RLC status report prohibit timer, which prohibits the RLC status report for a predetermined time, is running, and if the RLC status report prohibit timer is running, the cause of the RLC status report is checked, And, if the RLC status report is triggered due to a polling PDU, a status report controller for generating the RLC status report and a status report processor for generating the RLC status report under control of the status report controller. do.

In the mobile communication system according to the present invention, a method for processing radio link control (RLC) data includes setting and transmitting a poll bit to a last RLC PDU among RLC packet data units (PDUs), driving a poll retransmission timer, and Checking whether a new RLC PDU exists after the poll retransmission timer expires, and if the new RLC PDU does not exist, setting the poll bit to the smallest RLC PDU among the RLC PDUs currently stored in the buffer. And retransmitting the RLC PDU having the smallest set size of the poll bit.

According to the present invention, by preventing the STATUS REPORT transmission triggered by the polling PDU in the RLC receiving apparatus from being delayed by the STATUS REPORT prohibit timer, it is possible to prevent the polling PDU from being unnecessarily retransmitted from the RLC transmitting apparatus.

In addition, the present invention has an advantage of increasing the efficiency of packet transmission by preferentially processing new RLC PDU transmissions as the RLC transmitting apparatus requests STATUS REPORT in consideration of the existence of a new RLC PDU. Or, if there is no new RLC PDU, the RLC transmitting apparatus has the advantage of requesting STATUS REPORT more efficiently as the poll bit is retransmitted by setting the last RLC PDU.

Hereinafter, an apparatus and an operation method of constructing the present invention will be described in detail with reference to the accompanying drawings. In the following description, specific matters such as internal configuration blocks of specific devices are shown, which are provided to help a more general understanding of the present invention, and such specific matters may be modified or changed within the scope of the present invention. Will be apparent to those of ordinary skill in the art.

In addition, in describing the present invention, when it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention proposes a method for efficiently processing packet data at a radio link state (RLC) layer in connection with transmission of packet data in a mobile communication system.

In particular, the present invention proposes a method for preventing excessive occurrence of RCL status reports in processing packet data between a transmitter and a receiver. In addition, the present invention provides a method for preventing processing delay of polling data by a timer driven for the purpose of preventing excessive occurrence of the RCL status report.

2 is a diagram illustrating a radio protocol structure applied to a UE and an ENB in an LTE system to which the present invention is applied.

Referring to FIG. 2, in the LTE system, the radio protocol layer is referred to as a packet data convergence protocol (PDCP) layer 205 and 240, and a radio link control (RLC). Layer 210, 235, medium access control (MAC) layer 215, 230, and physical layer (PHY) (220, 225). Is done.

First, the PDCP layers 205 and 240 are in charge of operations such as IP header compression / restore and secret / de-secret.

The RLC layers 210 and 235 reconstruct a packet data unit (hereinafter referred to as a 'PDU') generated from the PDCP layer to an appropriate size to perform an ARQ operation and the like, and the order of the RLC PDUs out of order in the ARQ process is performed. Rearrange the order. Here, the term PDU referred to means packet data output in a specific protocol layer. Hereinafter, the device of the RLC layer is referred to as an 'RLC device'.

The MAC layers 215 and 230 are connected to various RLC layer devices configured in the UE, and multiplex the RLC PDUs into MAC PDUs and demultiplex the RLC PDUs from the MAC PDU.

The physical layers 220 and 225 perform channel coding and modulation on the received upper layer data, make the OFDM symbols and transmit them to the wireless channel, or demodulate and channel decode the OFDM symbols received through the wireless channel. It acts to deliver to the layer.

The present invention provides a method of preventing the occurrence of a STATUS REPORT by a STATUS REPORT prohibit timer when the RLC device receives a polling PDU requesting a STATUS REPORT transmission from a counterpart RLC device. . On the other hand, polling is a transmission control method in which one program or device continuously checks whether other programs or devices are in a state. Generally, polling is a process of checking whether a counterpart device is in a transmission state or wants to transmit data. It can be briefly described.

According to the RLC protocol of the LTE system, if an unreceived RLC PDU is not received until a predetermined time elapses after an unreceived RLC PDU is found, the RLC device considers that the RLC PDU is lost, and the RLC STATUS Trigger the REPORT.

As described, the RLC STATUS REPORT is triggered by not receiving the RLC PDU is referred to as a 'missing PDU detection trigger'. Here, the trigger refers to a condition for generating the RLC STATUS REPORT. That is, when the RLC STATUS REPORT is triggered, the RLC device generates an RLC STATUS REPORT at the next transmission opportunity and transmits it to the counterpart RLC device, except when the RLC STATUS REPORT transmission is not prohibited for any reason.

Meanwhile, in the LTE system, when a lost RLC PDU is found, a polling triggers an RLC STATUS REPORT when a lost PDU detection trigger that triggers an RLC STATUS REPORT and an RLC PDU containing information requesting the transmission of a STATUS REPORT are received. (polling) A PDU Receive Trigger is defined.

The polling PDU is used to transmit an RLC STATUS REPORT message, and the poll bit of the RLC PDU header is set (set). The poll bit is one of the fields defined in the RLC header and can be expressed using 1 bit. That is, when the poll bit is set to 1, the receiver indicates that an RLC STATUS REPORT should be generated and transmitted. In addition, the present invention may indicate that the RLC STATUS REPORT should be generated and transmitted when the poll bit is set to a value of 0 according to the system designer's setting. However, in the present invention, for example, when the poll bit is set to 1, an RLC STATUS REPORT is generated.

If an unreceived RLC PDU is found, the RLC layer device waits for a period of time without immediately considering the unreceived RLC PDU as a lost RLC PDU. This is because the RLC PDU is not mistaken as a lost RLC PDU in consideration of the HARQ reception process.

Meanwhile, in the present invention, the RLC layer device may transmit or receive an RLC PDU. That is, the RLC layer device may be provided separately from the RLC transmitting device and the RLC receiving device to operate independently. The RLC transmitting apparatus and the RLC receiving apparatus may be provided as the same single apparatus, and may be called an RLC transmitting apparatus or an RLC receiving apparatus according to an operation to be performed. Hereinafter, an RLC transmitting apparatus for transmitting an RLC PDU among RLC layer apparatuses provided in each of a UE and an ENB, and an RLC processing apparatus for receiving an RLC PDU transmitted from the RLC transmitting apparatus will be described as an RLC receiving apparatus.

If the radio link state is poor, i.e., in a state where the radio channel environment is unstable, the RLC PDU may be repeatedly lost, and thus the RLC STATUS REPORT may be excessively generated by the lost PDU detection trigger. To prevent this, the RLC receiving apparatus transmits an RLC STATUS REPORT, drives a predetermined timer called an RLC STATUS_PROHIBIT Timer, and controls not to transmit an RLC STATUS REPORT while the timer is running.

In other words, when the STATUS_PROHIBIT timer is running, even if a polling PDU is received, the RLC receiving device does not transmit the RLC STATUS REPORT until the STATUS_PROHIBIT timer expires. In addition, since the RLC receiving apparatus cannot determine whether the last RLC PDU is lost due to the property of the RLC PDU, the RLC transmitting apparatus sets the polling bit of the last RLC PDU to be transmitted to 1, which is then transmitted to the RLC receiving apparatus. send.

At this time, if the RLC STATUS REPORT is not received from the RLC receiving apparatus within a predetermined period, the RLC transmitting apparatus determines that the PDU in which the polling bit is set to 1 is lost, and retransmits the PDU in which the polling bit is set.

On the other hand, when the RLC receiving apparatus that receives the polling PDU with the polling bit set delays the transmission of the RLC STATUS REPORT under the control of the RLC STATUS_PROHIBIT timer, the RLC transmitter transmits the PDU having the polling bit set to the lost. And incorrectly retransmit a polling PDU to the RLC receiving device.

Accordingly, the present invention proposes a method for preventing the RLC transmitting apparatus from unnecessarily retransmitting a polling PDU to the RLC receiving apparatus as described above. That is, the present invention proposes a method for efficiently transmitting RLC status report transmission and polling PDU transmission between the RLC transmitting apparatus and the RLC receiving apparatus.

<First Embodiment>

According to the first embodiment of the present invention, in order to prevent the transmission of the RLC STATUS REPORT triggered by the polling PDU from being delayed by the RLC status report prohibit timer (RLC_STATUS_PROHIBIT Timer), the RLC receiving apparatus operates the RLC_STATUS_PROHIBIT timer. If an RLC STATUS REPORT is triggered in the current situation, first check what caused the RLC STATUS REPORT to be triggered.

If it is determined that the RLC STATUS REPORT is triggered by receiving the polling PDU, the RLC STATUS REPORT is immediately transmitted. On the other hand, if it is determined that the RLC STATUS REPORT is triggered as a result of the discovery of the missing PDU, the RLC STATUS REPORT waits until the RLC_STATUS_PROHIBIT timer expires and then transmits the RLC STATUS REPORT. That is, it delays the transmission of the RLC STATUS REPORT and prevents the unnecessary transmission of the RLC STATUS REPORT in advance.

3 is a diagram illustrating an operation of an RLC device according to a first embodiment of the present invention. In particular, FIG. 3 illustrates a process for preventing unnecessary retransmission of a polling PDU according to the first embodiment of the present invention. That is, it illustrates that the STATUS PDU triggered by the polling PDU is delayed, thereby preventing the polling PDU from being unnecessarily retransmitted.

Referring to FIG. 3, in step 305, the RLC device determines that an RLC STATUS REPORT is triggered.

In step 310, the RLC device checks whether an RLC STATUS_PROHIBIT timer that prohibits RLC STATUS REPORT transmission is running. If the RLC STATUS PROHIBIT timer is not driven, the RLC device proceeds to step 315.

In step 315, the RLC device informs the state-side RLC device of its RLC state by transmitting an RLC STATUS REPORT. If the RLC device is the RLC device of the UE, the RLC STATUS REPORT transmission procedure, the UE requests the transmission resource allocation to the ENB, and transmits the RLC STATUS REPORT using the allocated transmission resources. At this time, the UE may update the contents of the RLC STATUS REPORT immediately before transmitting the RLC STATUS REPORT.

On the other hand, when the RLC STATUS PROHIBIT timer is running, the process proceeds to step 320. In step 320, the RLC device checks the cause of triggering the RLC STATUS REPORT. Here, according to the test result of step 320, the RLC device determines whether to immediately transmit the RLC STATUS REPORT or after the RLC STATUS PROHIBIT timer expires.

If it is determined that the RLC status report has received the polling PDU, the RLC processing apparatus proceeds to step 315 to start the RLC status report transmission procedure. This is because the polling PDU may be unnecessarily retransmitted when the RLC STATUS REPORT is delayed.

On the other hand, if the RLC STATUS REPORT occurs because the lost PDU is detected as a result of step 320, the RLC device must comply with the RLC STATUS_PROHOBIT timer, and proceeds to step 325 and waits for the RLC STATUS PROHIBIT timer to expire. After that, the transmission procedure of the RLC STATUS REPORT is started.

<< second embodiment >>

In the second embodiment of the present invention, if a lost PDU is found, the RLC receiving apparatus checks whether there is a polling PDU among packets whose HARQ order has not been rearranged, and if there is a polling PDU whose order is not rearranged, by a lost PDU detection trigger. Cancel the triggered RLC STAUS REPORT.

This is because the RLC STATUS REPORT will be triggered in the near future when the reordering of the polling PDUs is complete. Here, the reason why the RLC STATUS REPORT is triggered when the reordering of the polling PDUs is completed is because an RLC STATUS REPORT is generated when the reordering of the polling PDUs is not completed.

For example, if the polling PDU has a serial number of 10 and PDU 9 has been missed and the reordering of the polling PDUs has not been completed, it is not clear whether PDU 9 is receiving or missing HARQ. Since the reordering is completed, the trigger is executed.

On the other hand, if the RLC STATUS REPORT is generated and transmitted by the lost PDU detection trigger, the transmission of the triggered RLC STATUS REPORT is delayed by the RLC STATUS PROHIBIT timer after the order of polling PDUs is rearranged.

4 illustrates a process of transmitting an RLC status report according to a second embodiment of the present invention.

Referring to FIG. 4, the RLC receiving apparatus receives an RLC PDU [2] 410, an RLC PDU [3] 415, and an RLC PDU [4] (without receiving an RLC PDU [1] at any time). 420, assume that an RLC PDU [5] 425 has been received. In this case, the unreceived RLC PDU [1] may be in the process of HARQ processing.

Here, HARQ (Hybrid Automatic Request) processing means that the HARQ receiving process, and receives the RLC PDU [1] transmitted HARQ, performs a CRC check, if the CRC fails as a result of the check, transmits a NACK to the transmitting side In addition, it means a series of operations of soft combining by receiving the retransmission of the RLC PDU [1]. That is, the RLC receiving apparatus does not immediately determine a lost PDU for an unreceived RLC PDU, but waits for an RLC PDU to be received for a certain period of time.

More specifically, when the RLC receiving apparatus determines that an unreceived RLC PDU [1] is generated, the RLC receiving apparatus drives a T_reordering timer and waits for reception of the unreceived RLC PDU [1] for a predetermined period of time. If the unreceived RLC PDU [1] is not received until the T_reordering timer expires, it is confirmed that the unreceived RLC PDU [1] is not delayed due to HARQ processing. Here, the T_reordering timer is a timer that counts the time that the unreceived RLC PDU can be delayed due to HARQ processing. The T_reordering timer performs counting for a time defined by the system operator.

As the unreceived RLC PDU is not received until the T_reodering timer expires, the RLC receiving apparatus, which has confirmed that the unreceived RLC PDU is not a reception delay due to HARQ processing, must retransmit the unreceived PDU through an RLC ARQ process. Check.

If an RLC PDU [1] is not received until the T_reordering timer expires, the RLC receiver determines that the RLC PDU is lost, generates an RLC STATUS REPORT, and sends the lost RLC PDU to the RLC transmitter, for example. Request retransmission of RLC PDU [1]. In this case, ACK / NACK, which is a reception state of RLC PDUs, in which HARQ order rearrangement is completed, is stored in the RLC STATUS REPORT transmitted to the RLC transmitting apparatus. HARQ order reordering is considered complete if any RLC PDU [x] meets the following conditions. And, [] means the serial number of the PDU.

HARQ order reordering condition

If there is no unreceived RLC PDU with a serial number lower than x, or if the unreceived RLC PDU is already an unreceived RLC PDU with HARQ order reordering already completed, the HARQ order reordering is considered to be completed until the serial number x. Therefore, when the T_reordering timer of the corresponding PDU expires, the reordering is considered complete. The HARQ order reordering of any unreceived RLC PDU is completed, which means that the T_reordering timer for the unreceived RLC PDU has expired.

The value obtained by adding 1 to the highest serial number of the sequence rearranged RLC PDU is stored in the VR (MS) variable, which is a variable defined in the present specification, and the serial number lower than the VR (MS) is included in the RLC STATUS REPORT. Has a reception status of RLC PDUs.

Here, the reason for adding 1 to the highest serial number among the serial numbers of the rearranged RLC PDUs is to use the VR (MS) as the ACK_SN of the RLC STATUS PDU. Since the RLC PDUs of the serial number higher than the VR (MS) have not been rearranged in HARQ order, the reception status of the RLC PDUs of the serial number higher than the VR (MS) is not reported as included in the RLC STATUS REPORT.

In addition, if the polling PDU has a higher serial number than the VR (MS), after the VR (MS) is updated to a value higher than the serial number of the polling PDU, an RLC STATUS REPORT is generated.

VR (MS) is 1 since the RLC PDU whose HARQ order rearrangement is completed at time t0 of FIG. 4 is an RLC PDU [0]. The PDU [0] 405, the PDU [2] 410, the PDU [3] 415, the PDU [4] 420, and the PDU [5] 425 are received by the RLC receiver at time t0. Serial numbers of the PDU. On the other hand, the shaded RLC PDU [1] is a PDU that the RLC receiving apparatus has not yet received, and may be in the course of HARQ processing.

At the time t1, a polling PDU having a polling bit set to a predetermined value, for example, 'P = Yes' is received in a header of the PDU [7]. At the time t1, VR (MS) is '1' and VR (X) is 2. Since the received polling PDU, that is, the serial number of the PDU [7] is higher than '1' which is VR (MS), it does not generate an RLC STATUS REPORT. In other words, since the HARQ order reordering for the polling PDU is not completed, that is, because the T_reordering timer is running, the RLC receiving device does not respond to the polling PDU and does not generate an RLC STATUS REPORT.

Thereafter, when the T_reordering timer expires at time t2, the expiration of the T_reordering timer causes the update of VR (MS), VR (X)), transmission of the RLC STATUS REPORT, and driving of the RLC STATUS_PROHIBIT timer.

VR (MS) update: updated with the serial number of the first unreceived RLC PDU with a serial number higher than VR (X). Update to 6 at t2.

VR (X) update: updated to one higher than the serial number of the last unreceived RLC PDU with a serial number higher than the current VR (X). At t2, VR (X) is updated to 7.

The VR (X) is a variable related to the driving of the T_reordering timer and stores the serial number of the RLC PDU that caused the T_reordering timer to be driven. For reference, if there are no more unreceived RLC PDUs after the T_reordering timer expires, the T_reordering timer is not driven and VR (X) is updated to 'no value'.

In addition, since the T_reordering timer has expired at time t2, the RLC receiving apparatus generates an RLC STATUS REPORT containing the reception status information of RLC PDUs having a serial number lower than VR (MS) and transmits it to the RLC transmitting apparatus. Then, the RLC STATUS_PROHIBIT timer is driven.

Here, since there is a PDU [6] whose order is not rearranged at the time of transmitting the RLC STAUTS REPORT, the RLC receiving apparatus arranges HARQ order for the polling PDU, that is, VR (MS) sets a series of polling PDUs. After updating to a value higher than the number, trigger RLC STATUS REPORT. For example, after receiving the PDU [6] 435 at time t3, a new RLC STATUS REPORT trigger by the polling PDU is performed.

In this case, the triggered RLC STATUS REPORT is delayed until the RLC STAUTS_PROHIBIT timer expires, which may cause unnecessary retransmission of the polling PDU.

As described above, since the RLC STATUS PDU is not transmitted when the RLC STATUS_PROHIBIT timer is running, the delay of the RLC STATUS PDU triggered by the polling PDU may cause unnecessary retransmission of the polling PDU.

Accordingly, in the second embodiment of the present invention, in order to prevent the delay of the STATUS PDU triggered by the polling PDU, the sequence reordering is triggered after triggering the RLC STATUS REPORT according to the expiration of the T_reordering timer at time t2. If there is no polling PDU that is not, i.e., serial number is higher than VR (MS), and if there are polling PDUs that are not reordered, cancel the triggered RLC STATUS REPORT. Because reordering of the polling PDUs will be completed in the near future and a newly triggered RLC STATUS REPORT will be sent immediately without the RLC STATUS_PROHIBIT timer running, retransmission of polling PDUs due to transmission delay of RLC STATUS REPORT and This is because the same malfunction may not occur.

In addition, the new RLC STATUS REPORT has an advantage of preventing frequent transmission of the RLC STATUS REPORT as all the state information that has been stored in the canceled RLC STATUS REPORT is stored.

5 is a signal flowchart illustrating an RLC processing operation according to a second embodiment of the present invention.

Referring to FIG. 5, when the T_reordering timer expires in step 505, the RLC receiver proceeds to step 510 to trigger an RLC STATUS REPORT.

In step 515, the RLC receiver checks whether the RLC STATUS_PROHIBIT timer is running. As a result of the check, if the RLC STATUS_PROHIBIT timer is running, the process proceeds to step 520. On the other hand, if the RLC STATUS_PROHIBIT timer is not running, the process proceeds to step 525.

When the RLC STATUS_PROHIBIT timer is driven, the transmission of the triggered RLC STATUS REPORT is prohibited for a predetermined time. In step 520, the RLC receiving apparatus waits for the transmission of the RLC STATUS REPORT until the RLC STATUS_PROHIBIT timer expires. .

In step 525, the RLC receiving apparatus determines whether to transmit the RLC status report. In step 525, the RLC receiving apparatus checks whether there is a polling PDU whose order reordering is not completed. Here, the presence of a polling PDU that has not yet completed order reordering means that an RLC STATUS REPORT is triggered by the polling PDU in the near future. Accordingly, the RLC receiving apparatus proceeds to step 530 to cancel generation of the RLC STATUS REPORT triggered by the expiration of the T_reordering timer.

On the other hand, if there is no polling PDU whose order reordering is not complete as a result of the check in step 525, the RLC receiving apparatus generates an RLC STATUS REPORT in step 535 and transmits it to the RLC transmitting apparatus.

As described above, whether or not the reordering of the polling PDUs is completed may be determined by comparing the serial number of the polling PDU with the VR (MS) at the corresponding time. If the serial number of the polling PDU is greater than or equal to VR (MS), it means that the HARQ order is not rearranged. If the serial number of the polling PDU is smaller than VR (MS), it means that the order is rearranged.

<< Third Embodiment >>

In a third embodiment of the present invention, a method of retransmitting a polling PDU by an RLC device will be described. The RLC device sets the polling bit while transmitting the last RLC PDU. Hereinafter, for convenience of explanation, an RLC PDU in which a polling bit is set is referred to as a polling PDU. The RLC device drives the poll retransmission timer while transmitting the polling PDU and retransmits the polling PDU if the RLC STATUS REPORT is not received until the poll retransmission timer expires.

6 is a diagram illustrating a retransmission process of a polling PDU to which the present invention is applied.

Referring to the LTE specification, if the poll retransmission timer expires but there are no more new RLC PDUs to transmit, the RLC transmitting apparatus retransmits an RLC PDU whose serial number is [VT (S) -1]. VT (S) is a variable that is incremented by one each time a new RLC PDU is transmitted, and indicates which serial number should be assigned when the RLC transmitting apparatus transmits a new RLC PDU. Therefore, the VT (S) has a value higher than the highest serial number of the serial numbers of the RLC PDUs transmitted so far.

Referring to FIG. 6, an example in which an RLC transmitting apparatus transmits PDUs [0] to PDU [5] is given. When the RLC transmitting apparatus initially transmits the PDU [0] 605, the VT (S) is increased to 1, and when the PDU [1] 610 is transmitted, the VT (S) is increased to 2. Finally, if PDU [5] 630 is transmitted, VT (S) is updated to 6. If the PDU [5] is the last PDU, the RLC transmitting apparatus sets and transmits the polling bit of the PDU [5] and drives the poll retransmission timer.

If no RLC STATUS REPORT is received until the poll retransmission timer expires, and there are no new RLC PDUs to transmit when the poll retransmission timer expires, the RLC transmitter sends an RLC PDU with a serial number lower than VT (S), that is, an RLC PDU. Resend [5]. When the RLC transmitting apparatus receives the RLC STATUS REPORT from the counterpart RLC receiving apparatus, the RLC transmitting apparatus discards the RLC PDUs marked as normally received from the RLC STATUS REPORT in the buffer.

For example, the RLC transmitting apparatus confirms that reception is normally completed up to the RLC PDU [5] without an error in the counterpart RLC receiving apparatus through the received RLC STATUS REPORT, and PDUs [0] to PDU [5] stored in a buffer are completed. Discard it.

However, if the RLC PDU having a serial number lower than VT (S) needs to be retransmitted when the poll retransmission timer expires, the RLC PDU marked as normally received in the RLC STATUS REPORT cannot be discarded from the buffer.

For example, if the RLC transmitting apparatus sets the poll bit while transmitting the RLC PDU [5], and the RLC STATUS REPORT arrives before the poll retransmission timer expires, PDU [0], PDU [1] is sent to the RLC STATUS REPORT. ], PDU [2], PDU [3], and PDU [5] are marked as well received, while PDU [4] is marked as not being received, the RLC transmitting device is assigned to PDU [0], PDU. [1], PDU [2], PDU [3], PDU [5] are discarded from the buffer and PDU [4] is retransmitted.

Here, if there is no new data other than the PDU [4], the RLC transmitting apparatus sets and transmits a poll bit of the PDU [4] and drives a poll retransmission timer. If the RLC STATUS REPORT is not received until the poll retransmission timer expires, a situation occurs in which the RLC transmitting apparatus retransmits an RLC PDU [5] having a serial number one lower than VT (S), that is, serial number 5. However, the RLC PDU [5] has already been discarded in the buffer.

Accordingly, in the present invention, when the poll retransmission timer expires and there is no new data in connection with the retransmission of the PDU in which the poll bit is set, the RLC PDU having the highest serial number among the RLC PDUs currently stored in the buffer is retransmitted. Suggest a solution.

7A is a diagram illustrating an RLC processing operation according to a third embodiment of the present invention.

Referring to FIG. 7A, when the poll retransmission timer expires in step 705, the RLC transmitting apparatus proceeds to step 710 to check whether there is new data that has not yet been transmitted. If there is no new data, the process proceeds to step 715 and if there is new data, the process proceeds to step 717.

In step 717, the RLC transmitting apparatus performs the new data transmission process according to a conventional procedure, sets the poll bit while transmitting the last new RLC PDU, and transmits it.

On the other hand, if there is no new data, in step 715, the RLC transmitting apparatus triggers retransmission of the RLC PDU having the highest serial number among the RLC PDUs stored in the buffer. The RLC PDU having the highest serial number among the RLC PDUs stored in the buffer is also the RLC PDU having the highest serial number among the RLC PDUs for which a positive acknowledgment signal has not yet been received. Meanwhile, the RLC transmitting apparatus notifies the MAC if there is data to be transmitted, and the MAC instructs the RLC transmitting apparatus to transmit the RLC PDU when the transmission resource is allocated.

Accordingly, when the transmission opportunity occurs in step 720, that is, when the MAC instructs the transmission of the RLC PDU, the RLC transmitting apparatus proceeds to step 725 to check whether there is newly generated data in the RLC buffer.

If there is newly generated data, it is more efficient to transmit new data than to retransmit the RLC PDU whose retransmission was triggered in step 715. Therefore, the RLC transmitting apparatus proceeds to step 735 to cancel the retransmission of the triggered RLC PDU. Perform the transmission process for the data. In addition, the RLC transmitting apparatus transmits by setting the poll bit while transmitting the last new RLC PDU.

On the other hand, if it is determined in step 725 that there is no new data, the RLC transmitting apparatus proceeds to step 730 and performs retransmission of the RLC PDU in which retransmission is triggered in step 715. At this time, after transmitting the RLC PDU triggered by the retransmission, since there is no new data to transmit anymore, the poll bit is set to the RLC PDU triggered by the retransmission according to a normal procedure and transmitted.

On the other hand, when performing retransmission after the poll retransmission timer expires, it is advantageous in terms of efficiency of transmission resources to retransmit the smallest RLC PDU if possible. Therefore, according to another example of the third embodiment of the present invention, if the RLC transmitting apparatus has no new data after the poll retransmission timer expires and there is no RLC PDU whose serial number is VT (S) -1, The smallest RLC PDU among the currently stored RLC PDUs may be retransmitted.

7B is a diagram illustrating another example of an RLC processing operation according to a third embodiment of the present invention.

Referring to FIG. 7B, when the poll retransmission timer expires in step 750, the RLC transmitting apparatus proceeds to step 755 to check whether there is new data that has not yet been transmitted.

If there is no new data, the process proceeds to step 765, while if there is new data, the process proceeds to step 760. In step 760, the RLC transmitting apparatus performs the new data transmission process according to a conventional procedure, and sets the poll bit when transmitting the last new RLC PDU.

On the other hand, if there is no new data, in step 765, the RLC transmitting apparatus checks whether an RLC PDU having a serial number VT (S) -1 exists. If the RLC PDU having the serial number VT (S) -1 exists, the flow proceeds to step 775 to trigger retransmission of the RLC PDU having the VT (S) -1. On the other hand, if there is no RLC PDU whose serial number is VT (S) -1, the process proceeds to step 770.

In step 770, the RLC transmitting apparatus triggers retransmission of the smallest RLC PDU among the RLC PDUs stored in the buffer. The smallest RLC PDU among the RLC PDUs stored in the buffer is also the smallest RLC PDU among the RLC PDUs for which a positive acknowledgment signal has not yet been received.

Meanwhile, the RLC transmitting apparatus notifies the MAC that there is data to be transmitted, and the MAC instructs the RLC transmitting apparatus to transmit the RLC PDU when the transmission resource is allocated. In step 780, the RLC transmitter confirming that a transmission opportunity has occurred, that is, confirming a transmission instruction of the RLC PDU from the MAC, proceeds to step 785.

In step 785, the RLC transmitting apparatus checks whether there is data newly generated in the RLC buffer in relation to the allocated transmission resource. If it is confirmed in step 785 that the newly generated data exists, it is more efficient to transmit new data than to retransmit the RLC PDU triggered by retransmission, so the RLC transmitting apparatus proceeds to step 795 to retransmit the triggered RLC PDU. Cancel the transmission and perform the transmission on the newly generated data. At this time, the RLC transmitting apparatus sets and transmits a poll bit while transmitting the last new RLC PDU.

On the other hand, if it is confirmed in step 785 that there is no newly generated data, the RLC transmitting apparatus proceeds to step 790 and the smallest RLC PDU triggered by retransmission in step 770 or the VT (S) having a serial number in step 775. Retransmission of the RLC PDU equal to −1 is performed. After transmitting the retransmission RLC PDU and confirming that there is no more data to transmit, the poll bit is set to the smallest RLC PDU and transmitted. Alternatively, the poll bit is set in the RLC PDU having the serial number VT (S) -1 and transmitted.

8 is an internal block diagram of an RLC device according to the present invention.

Referring to FIG. 8, the RLC apparatus 800 includes a transmission controller 805, a transmission buffer 810, a framing apparatus 815, a retransmission buffer 820, a STATUS REPORT processing unit 840, a reception buffer 845, and a STATUS. REPORT control unit 855 and the like.

The RLC apparatus 800 may be connected to the multiplexer 825 and the demultiplexer 850 according to a transmission and reception operation to operate as an RLC receiver or an RLC transmitter. In particular, the term RLC device used throughout the detailed description of the invention encompasses both an RLC receiving device and an RLC transmitting device. In addition, in the present invention, the reception buffer 845, the STATUS REPORT processing unit 840, and the STATUS REPORT control unit 855 correspond to the RLC receiving apparatus.

The multiplexer 825 multiplexes the RLC PDUs delivered from multiple RLC devices 800 into one HARQ packet.

The demultiplexer 850 demultiplexes the HARQ packet transmitted from the HARQ processor 830 and delivers it to the appropriate RLC device 800.

The HARQ processor 830 is an apparatus for transmitting and receiving HARQ packets through a predetermined HARQ operation, and the transceiver 835 modulates and transmits a HARQ packet into a radio signal and demodulates the radio signal.

The operation of the RLC device 800 will be described in more detail.

The data transmitted from the upper layer (PDCP layer) is stored in the transmission buffer 810, and is framed and transmitted as an RLC PDU of an appropriate size under the control of the transmission control unit 805. The transmission control unit 805 reports the amount of data to be transmitted to the lower layer (MAC layer), and is informed of the amount of data to be transmitted in the next transmission period from the lower layer. The data to be transmitted is determined in the next transmission period according to the amount of data to be transmitted. The amount of data to be transmitted may be set in consideration of the amount of data stored in the transmission buffer 810, the amount of data stored in the retransmission buffer, and the size of other control information such as a reception status report.

The framing device 815 attaches an RLC header to the data delivered from the transmit buffer 810 to create an RLC PDU. The RLC PDU is delivered to the multiplexer 825 and stored in the retransmission buffer 820. The RLC PDU stored in the retransmission buffer 820 is retransmitted at the request of the other side RLC device, or is removed by the transmission control unit 805 when it is confirmed that the RLC PDU is successfully transmitted.

The RLC PDU delivered by demultiplexer 850 is stored in receive buffer 845. The STATUS REPORT control unit 855 determines whether to generate an RLC STATUS REPORT in consideration of whether the RLC STATUS REPORT trigger is satisfied, whether the RLC STATUS_PROHIBIT timer is driven, and whether there is a polling PDU whose order is not rearranged. In response to the determination, the status report control unit 855 instructs the RLC status report processing unit 840 to generate the status report.

That is, even if the RLC STATUS REPORT is triggered by the expiration of the T_reordering timer, if an unordered polling PDU is stored in the reception buffer 845, the STATUS REPORT control unit 855 generates and transmits the triggered RLC STATUS REPORT. Cancel. In addition, the STATUS REPORT control unit 855 stores variables such as the above-described VR (MS) and VR (X) according to an embodiment of the present invention, and manages the variables.

More specifically, according to the first embodiment of the present invention, when the RLC STATUS REPORT is triggered while the RLC_STATUS_PROHIBIT timer is running, the STATUS REPORT control unit 855 checks for what cause the RLC STATUS REPORT is triggered. This is to prevent the transmission of the RLC STATUS REPORT triggered by the polling PDU to be delayed by the RLC_STATUS_PROHIBIT timer.

Accordingly, if the RLC status report is triggered as the polling PDU is received, the status report control unit 855 controls the status report processing unit 840 to immediately transmit the RLC status report.

On the other hand, if the RLC STATUS REPORT is triggered as a loss PDU is found, the STATUS REPORT control unit 855 delays the transmission of the RLC STATUS REPORT until the RLC_STATUS_PROHIBIT timer expires, the STATUS REPORT processing unit 640 To control.

In addition, according to the second embodiment of the present invention, if the non-received RLC PDU is not received until the T_reordering timer expires, the STATUS REPORT control unit 855 determines that the RLC PDU is lost and triggers an RLC STATUS REPORT. In addition, the STATUS REPORT control unit 855 checks whether there is a polling PDU in which the HARQ order rearrangement is not completed in the reception buffer 845.

If there is a polling PDU for which HARQ order reordering is not completed, cancel the triggered RLC STATUS REPORT. On the other hand, if there is no polling PDU for which HARQ order rearrangement is not completed, the STATUS REPORT processing unit 840 controls to generate an RLC STATUS REPORT. At this time, the STATUS REPORT processing unit 840 may be different from the point in time at which the RLC STATUS REPORT is generated and the actual transmission point, and after generating and updating the RLC STATUS REPORT under the control of the STATUS REPORT control unit 855, the multiplexer 825 To pass). That is, the status report control unit 855 controls the RLC status report generated by the status report processing unit 840 and outputs it to the multiplexer 825.

In addition, according to the third embodiment of the present invention, the RLC PDU delivered from the demultiplexer 850 is stored in the reception buffer 845, and the STATUS REPORT control unit 855 and the STATUS REPORT processing unit 840 provide a STATUS REPORT. It is responsible for receiving and taking necessary actions, or generating a status report when certain conditions are met. The transmission control unit 805 sets the poll bit of the RLC PDU and drives the poll retransmission timer while transmitting the last RLC PDU.

If the STATUS REPORT is not received and there is no new data to transmit until the poll retransmission timer expires, the serial number of the RLC PDUs stored in the buffer triggers retransmission of the highest serial number. And, before actually retransmitting the retransmission-triggered RLC PDU, it is checked whether there is newly generated data, and if the newly generated data exists, cancel retransmission of the retransmission-triggered RLC PDU for retransmission of the polling PDU and Send the data.

According to another example of the third embodiment of the present disclosure, the transmission controller 805 may trigger retransmission of the RLC PDU having the smallest size among the RLC PDUs currently stored in the retransmission buffer 820. Here, if there is an RLC PDU having a serial number VT (S) -1, and if there is no RLC PDU having the serial number VT (S) -1, retransmission of the smallest RLC PDU is performed. Trigger The poll bit is set in the RLC PDU having the smallest retransmission triggered size and transmitted.

Here, before retransmitting the RLC PDU having the smallest triggered retransmission, it is again checked whether there is newly generated data, and if it is confirmed that the newly generated data exists, the RLC PDU having the smallest triggered retransmission has the smallest size. Cancel the retransmission of and transmit the new data.

<< fourth embodiment >>

In the fourth embodiment of the present invention, a method of determining whether the polling bit is set by the RLC device will be described. After transmitting any RLC PDU, the RLC transmitting apparatus according to the fourth embodiment of the present invention sets the polling bit of the RLC PDU to 1 when it is expected that no more data remains to be transmitted in the RLC transmission buffer. . This is because, when the RLC PDU is the last RLC PDU, the RLC receiving apparatus cannot determine whether the RLC PDU is lost by itself. For example, if the RLC PDU with serial number x is the last RLC PDU and the RLC PDU is lost during transmission, the receiving device may know whether the RLC PDU [x] is missing because there is no RLC PDU with serial number greater than x. none.

Meanwhile, in the LTE mobile communication system, a transmission buffer is also provided in the PDCP device, and even if the RLC transmission buffer transmits the last RLC PDU, if there is data to be transmitted in the PDCP transmission buffer, new data of the PDCP buffer is stored in the RLC transmission buffer within a short time period. Is likely to be delivered to. Therefore, determining whether the polling bit is set by considering only the state of the RLC transmit buffer may cause unnecessary polling.

Accordingly, in the fourth embodiment of the present invention, in consideration of this, the RLC transmitting apparatus checks whether there is new data to be transmitted to the PDCP transmission buffer while transmitting the last RLC PDU, and sets the polling bit of the RLC PDU to 1; Judge.

9 is a diagram illustrating an RLC transmitting apparatus according to a fourth embodiment of the present invention.

Referring to FIG. 9, in step 905, the RLC transmitting apparatus configures an RLC PDU. Step 905 occurs when a transmission opportunity is granted to the RLC transmitting apparatus.

In the LTE mobile communication system, transmission resources are managed by a MAC device, and the MAC device determines the amount of data to be transmitted for each logical channel by considering the priority of the logical channel and the amount of data stored in the logical channel. Notify the RLC device of the logical channel. Here, the logical channel refers to a PDCP device and an RLC device configured for each service together.

When the RLC device is instructed to transmit data of an arbitrary size, the RLC device configures an RLC PDU of the corresponding size, sets the polling bit to an appropriate value, and delivers the data to the MAC layer. At this time, if there is no data to be transmitted in the transmission buffer of the RLC device or the amount of data is insufficient, the RLC device receives new data from the PDCP device to configure an RLC PDU of the indicated size.

In step 910, the RLC transmitting apparatus checks whether the configured RLC PDU is the last RLC data. In other words, after transmitting the RLC PDU, it is checked whether there is no more data to transmit in the RLC transmit buffer and retransmission buffer. In this case, the RLC retransmission buffer may also store 'an RLC PDU whose transmission status is unknown', in which an RLC ACK or NACK is not received. However, in step 910, the RLC PDU whose transmission status is not known is not considered. For example, except that the data is not stored in the RLC transmission buffer and the RLC retransmission buffer except for the RLC PDU whose transmission status is unknown, the RLC transmitting apparatus determines that the determination result of step 910 is true. If the determination result of step 910 is false, that is, if there is data in the transmission buffer or the retransmission buffer even after transmitting the RLC PDU, the RLC transmitting apparatus proceeds to step 920 and sets the polling bit of the RLC PDU to zero.

On the other hand, if the determination result of step 910 is true, that is, if there is no data in the RLC transmission buffer or retransmission buffer after transmitting the RLC PDU, the RLC transmitting apparatus proceeds to step 915.

In step 915, the RLC transmitting apparatus checks whether data to be transmitted to the PDCP apparatus exists. The data to be transmitted by the PDCP device means 'data that has not been transmitted to the RLC device in PDCP SDU or PDCP PDU yet.' Here, the existence of data to be transmitted to the PDCP device means that when the MAC device gives a transmission opportunity to the logical channel in the future, new data is delivered to the RLC transmitting device, and a new RLC PDU is configured from the new data.

That is, setting the polling bit to 1 is unnecessary because the RLC PDU to be transmitted at this time is not the last RLC PDU. Therefore, if the determination result of step 915 is true, the RLC transmitting apparatus proceeds to step 920 and sets the polling bit to zero.

On the other hand, if the determination result of step 915 is false, since the RLC PDU to be transmitted at this time is the last RLC PDU, the RLC transmitting apparatus proceeds to step 925 and sets the polling bit to 1.

FIG. 10 is a block diagram illustrating an internal block diagram of an RLC device and a PDCP transmitter according to a fourth embodiment of the present invention.

Referring to FIG. 10, the RLC apparatus 1000 may include a transmission controller 1005, a transmission buffer 1010, a framing apparatus 1015, a retransmission buffer 1020, a STATUS REPORT processing unit 1040, a reception buffer 1045, STATUS REPORT control unit 1055 or the like.

The RLC apparatus 1000 may be connected to the multiplexer 1025 and the demultiplexer 1050 according to a transmission and reception operation to operate as an RLC receiver or an RLC transmitter. In particular, the term RLC device used throughout the detailed description of the invention encompasses both an RLC receiving device and an RLC transmitting device. In addition, in the present invention, the reception buffer 1045, the status report processing unit 1040, and the status report control unit 1055 correspond to the RLC receiving apparatus.

The multiplexer 1025 multiplexes the RLC PDUs transmitted from the plurality of RLC devices 1000 into one HARQ packet.

The demultiplexer 1050 demultiplexes the HARQ packet transmitted from the HARQ processor 1030 and delivers it to the appropriate RLC apparatus 1000.

The HARQ processor 1030 is a device for transmitting and receiving HARQ packets through a predetermined HARQ operation, the transceiver 1035 is a device for modulating and transmitting the HARQ packet to a radio signal, demodulating the radio signal.

The operation of the RLC apparatus 1000 will be described in more detail. The data transmitted from the upper layer (PDCP layer) is stored in the transmission buffer 1010, and is framed and transmitted as an RLC PDU of an appropriate size under the control of the transmission control unit 1005.

When the transmission control unit 1005 is informed of the amount of data to be transmitted in the next transmission period from the lower layer, the transmission control unit 1005 determines the data to be transmitted in the next transmission period according to the amount of data to be transmitted. The amount of data to be transmitted is set in consideration of the amount of data stored in the transmission buffer 1010, the amount of data stored in the retransmission buffer, and the size of other control information such as a reception status report.

In addition, when determining that the amount of data to be transmitted is insufficient, the transmission control unit 1005 instructs the PDCP transmission apparatus to transfer new data. The PDCP transmitter includes a transmission buffer 1070, a header compression unit 1065, and a secreting unit 1060. The upper layer packet is stored in the transmission buffer 1070, and the stored packet is compressed and decoded through the header compression unit 1065 and the secreting unit 1060 at a suitable time and then transferred to the lower layer RLC apparatus 1000. Delivered.

In addition, if the last RLC PDU to which any RLC PDU is to be transmitted, the transmission control unit 1005 checks whether there is data to be transmitted in the PDCP transmission buffer at that time, and if there is no data to be transmitted, sets the polling bit of the RLC PDU to 1. .

The framing device 1015 attaches an RLC header to the data delivered from the transmit buffer 1010 to create an RLC PDU. The RLC PDU is delivered to the multiplexer 1025 and stored in the retransmission buffer 1020.

The RLC PDUs stored in the retransmission buffer 1020 are retransmitted at the request of the counterpart RLC device, or are removed by the transmission control unit 1005 when it is confirmed that the RLC PDUs have been successfully transmitted.

As described above, although the present invention has been described by the limited embodiments and the drawings, the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the appended claims and their equivalents.

1 is a diagram showing the structure of a mobile communication system to which the present invention is applied;

2 is a diagram illustrating a radio protocol structure of a mobile communication system to which the present invention is applied;

3 is a diagram illustrating an RLC processing operation according to a first embodiment of the present invention;

4 is a diagram illustrating a process of transmitting an RLC status report according to a second embodiment of the present invention;

5 is a diagram illustrating an RLC processing operation according to a second embodiment of the present invention;

6 is a diagram illustrating a retransmission process of a polling PDU to which the present invention is applied;

7A and 7B illustrate an RLC processing operation according to a third embodiment of the present invention;

8 is an internal block diagram of an RLC device according to the present invention;

9 illustrates an RLC processing operation according to a fourth embodiment of the present invention;

10 is an internal block diagram of an RLC transmitting apparatus and a PDCP transmitting apparatus according to a fourth embodiment of the present invention.

Claims (14)

A method for processing radio link control (RLC) data in a mobile communication system, Checking whether an RLC STATUS REPORT has been triggered to receive status for received RLC packet data units (PDUs); If the RLC status report is triggered, checking whether an RLC status report prohibit timer for prohibiting the RLC status report for a predetermined time is running; If the RLC status report prohibit timer is running, checking a cause of triggering the RLC status report; And if the RLC status report is triggered due to the polling PDU, transmitting the RLC status report. The method of claim 1, Waiting for the RLC status report prohibit timer to expire, if the RLC status report is triggered due to a lost PDU; And if the RLC status report prohibit timer expires, transmitting the RLC status report. In the radio link control (RLC) data processing method in a mobile communication system, If the first timer (T_reordering timer), which is the time at which the reception may be delayed due to HARQ processing of the unreceived RLC packet data unit (PDU), has expired, an RLC state containing the status for the received PDUs Triggering RLC STATUS REPORT, If the RLC status report is triggered, checking whether an RLC status report prohibit timer for prohibiting the RLC status report for a predetermined time is running; If the RLC status report prohibit timer is not running, checking whether there is a polling PDU whose order reordering is not completed yet; Canceling the generation of the RLC status report triggered by the first timer expiration, if the polling PDU exists; And if the polling PDU does not exist, generating and transmitting the RLC status report. In the radio link control (RLC) data processing apparatus in a mobile communication system, RLC status report to check whether RLC STATUS REPORT containing status for received packet data units (PDUs) has been triggered, and if the RLC status report is triggered, prohibit the RLC status report for a predetermined time Investigate whether the prohibit timer is running and report the RLC status If the prohibit timer is running, examine the cause of the trigger of the RLC status report, and if the RLC status report is triggered due to the polling PDU, as a result of the check, the RLC status A status reporting control unit which controls to generate a report; And a status report processor for generating the RLC status report under the control of the status report controller. The method of claim 4, wherein the status report control unit, If the RLC status report is triggered due to a lost PDU, wait until the RLC status report prohibit timer expires, and if the RLC status report prohibit timer expires, send the RLC status report to the status report. An apparatus for processing radio link control data in a mobile communication system, characterized by controlling a processing unit. In the radio link control (RLC) data processing method in a mobile communication system, Transmitting and setting a poll bit in the last RLC PDU of the RLC packet data units (PDUs), and driving a poll retransmission timer; Checking whether a new RLC PDU exists after the poll retransmission timer expires; If the new RLC PDU does not exist, setting the poll bit in the RLC PDU having the highest serial number among the RLC PDUs stored in the current buffer; And retransmitting the RLC PDU having the highest serial number. The method of claim 6, If the new RLC PDU exists, canceling the retransmission process; And transmitting the new RLC PDU. In the radio link control (RLC) data processing apparatus in a mobile communication system, A buffer for storing RLC packet data units (PDUs), Among the RLC PDUs, a poll bit is set to the last RLC PDU and transmitted, a poll retransmission timer is driven, and a new RLC PDU is present in the buffer during the poll retransmission timer. Otherwise, the transmission control unit retransmits the RLC PDU having the highest serial number by setting the poll bit in the RLC PDU having the highest serial number among the RLC PDUs stored in the buffer. Device. The method of claim 8, wherein the transmission control unit, If it is determined that a new RLC PDU exists in the buffer, canceling the retransmission and transmitting the new RLC PDU. In the radio link control (RLC) data processing method in a mobile communication system, Determining whether the RLC packet data unit (PDU) to be transmitted is the last RLC PDU; If the RLC PDU is the last RLC PDU, checking whether packet data convergence protocol (PDCP) data exists; If it is determined that the PDCP data is present, setting the poll bit of the last RLC PDU to 0 and transmitting the radio link control data. The method of claim 10, If it is confirmed that the RLC PDU to be transmitted is not the last RLC PDU, the method further comprises the step of transmitting by setting the poll bit of the RLC PDU to be transmitted to 0. The method of claim 11, If it is determined that the RLC PDU to be transmitted is the last RLC PDU and the PDCP data does not exist, the method further comprises the step of setting the poll bit of the last RLC PDU to 1 and transmitting the same. . In the radio link control (RLC) data processing apparatus in a mobile communication system, A PDCP apparatus that generates packet data convergence protocol (PDCP) data by compressing and encrypting data received from an upper layer; The RLC buffer receiving the PDCP data from the PDCP device to generate and store RLC packet data units (PDUs), and checking whether the PDCP device has generated transmission data, and whether the RLC PDU to be stored in the RLC buffer is the last RLC. And an RLC device including a transmission control unit for determining whether the PDU is a PDU, and setting the pole bit of the RLC PDU to be transmitted to 0 or 1 for transmission. In the radio link control (RLC) data processing method in a mobile communication system, Transmitting and setting a poll bit in the last RLC PDU of the RLC packet data units (PDUs), and driving a poll retransmission timer; Checking whether a new RLC PDU exists after the poll retransmission timer expires; If the new RLC PDU does not exist, setting the poll bit to the smallest RLC PDU among the RLC PDUs stored in the current buffer; And retransmitting the RLC PDU having the smallest set size of the poll bit.

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