KR100370060B1 - Method for operating communication in Next-generation Communication System - Google Patents

Abstract

According to the present invention, in the radio network control (RNC) of the direct spread (DS) type IMT-2000 system, the service data unit (SDU) received from the upper layer by the radio resource control layer (RLC) is divided into protocol data to control the homogeneous radio link. The purpose of the present invention is to provide a communication operation method of a next generation mobile communication system in which a loss rate of a service data unit appearing when an error occurs in a process of transmitting to a peer RLC layer and receiving a transmission is less affected by call control. The communication operation method of the next generation mobile communication system may include adding and transmitting an information field according to the importance of a service data unit (SDU) from a radio resource control (RRC) layer to a radio link control (RLC) layer. Updating, at the radio link control layer, abandonment level of the service data unit, determining whether transmission to the service data unit is completed, retransmitting if the transmission is not completed, and If the retransmission has failed, performing the retransmission once more, and if the retransmission fails again, repeating the retransmission in the disapproval mode by the quick repeat method. Therefore, the loss rate of data can be reduced and the call connection rate can be improved.

Description

Method for operating communication in Next-generation Communication System

The present invention relates to a communication operation of a next generation mobile communication system, and more particularly, to a protocol data for a service data unit (SDU) received from an upper layer by a radio resource control layer (RLC) at a radio network control station (RNC) of an IMT-2000 system. The present invention relates to a communication operation method of a next-generation mobile communication system in which a loss rate of service data unit, which occurs when an error occurs in a process of transmitting to a peer radio link control layer and receiving a transmission confirmation, is less affected by call control.

The conventional direct sequence (DS) type IMT-2000 system is composed of a core network (Core Network), a radio link control layer (hereinafter referred to as RLC), a base station and a terminal (UE: User Equipment).

Here, the RLC should be able to efficiently transmit and receive a call setup and user data without loss using a terminal and a signaling message.

Hereinafter, a method of operating a conventional next generation mobile communication system will be described with reference to the accompanying drawings.

FIG. 1 is a diagram illustrating a wireless network control station layer structure in a general direct spread IMT-2000 system.

In a general direct spread IMT-2000 system, in the wireless network control layer structure, when the RLC layers 3 and 4 operate in a control plane, the upper layer is a Radio Resource Control Layer (hereinafter referred to as RRC). (2), it can be referred to as a core network in the user plane (User Plane).

The RLC layer 4 operating in the user plane cannot determine the importance of a service data unit (hereinafter, abbreviated as SDU) received from a higher layer (Higher Layer (1)). The importance of the SDU could not be determined.

Here, before a call enters a call state, an upper layer that transmits an SDU to the RLC 3 layer is an RRC layer 2, and the RRC layer 2 is a Call Control (CC) or Mobility Management (MM) layer. In the case of a message, the SDU is sent to the RLC layer to deliver the message to the peer RRC layer without any analysis.

In the case of a radio resource message, the RRC layer 2 of the RNC 3 analyzes and transmits the same to the RRC. At this time, the SDU transmitted from the RRC layer to the RLC (3) does not reflect the importance of the SDU when the possibility of the loss of the SDU occurs, it is not possible to determine the importance of the SDU in the RLC (3) layer.

FIG. 2 is a diagram illustrating a format of a direct transmission message received in a core network of a conventional IMT-2000 system. FIG. 3 is a flowchart illustrating a procedure of transmitting a service data unit (SDU) including the direct transmission message shown in FIG. 2.

The direct transfer message format received from the core network of the conventional IMT-2000 system includes a message identifier 11 and a message length 12 indicating a direct transfer message, and the message compatibility information 13 is unrecognized. Information representing a message. The direct transmission information 14 includes information transmitted from a core network to a terminal. Therefore, when the information of this message is used, the RRC (2) layer transmits an SDU including this content to the RLC (3) layer, and the RRC (2) layer refers to this SDU as a Protocol Data Unit (hereinafter referred to as PDU). Segmentation) and transfers it to the acknowledgment mode with the same RLC layer (S1).

At this time, it is checked whether the same type RLC is well received using the STATUS PDU for the transmitted PDU, and the transmission rate of the SDU is increased by using a retransmission scheme when a transmission fails (S2).

However, despite the use of the retransmission scheme, if a STATUS PDU with confirmation information is not received from the peer RLC, the SDU is discarded. In this case, the SDU is checked without checking whether it must be delivered or discarded. Give up (S3).

In the conventional method of operating the next generation mobile communication system, the SDU received from the RLC layer at the radio network control station (RNC) fails to transmit and the SDU is abandoned. Since the abandonment cannot be performed, there is a problem in that the call cannot be set up only by the loss of one important SDU during transmission of several SDUs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and in the direct spread (DS) IMT-2000 system, the radio resource control layer (RLC) of the radio network control station (RNC) is a higher layer. In the next-generation mobile communication system, the service data unit (SDU) received from the PDU is transmitted to the peer RLC layer, and the loss rate of the service data unit, which occurs when an error occurs during transmission confirmation, is less affected by call control. It is to provide an operation method.

According to an aspect of the present invention for achieving the above object, the step of adding and transmitting the information field according to the importance of the service data unit (SDU) from the radio resource control (RRC) layer to the radio link control (RLC) layer and Updating the revocation level of the service data unit in the radio link control layer according to the information field, determining whether transmission to the service data unit is completed, and retransmitting if the transmission is not completed. Performing the retransmission once again if the retransmission has failed, and repeatedly performing the retransmission in a disapproval mode by the quick repeat method if the retransmission fails again.

Preferably, when an information field according to the importance of a service data unit (SDU) is added and transmitted from the radio resource control (RRC) layer to the radio link control (RLC) layer, a direct transfer message is indicated. A message processing level for determining the importance of the message is added to the direct transmission information including the message identifier, the message length, the message compatibility information indicating the unacknowledged message, and the information transmitted by the core network to the terminal.

According to the present invention as described above, there is an advantage that the loss rate of data can be reduced, and the call connection rate can be improved.

1 is a diagram illustrating a radio network control station (RNC) hierarchical structure in a general direct spread (DS) type IMT-2000 system;

2 is a diagram illustrating a format of a direct transmission message received from a core network of a conventional IMT-2000 system.

3 is a flowchart illustrating a procedure of transmitting a service data unit (SDU) including the direct transfer message shown in FIG.

4 is a flowchart illustrating a procedure of transmitting a service data unit (SDU) in an IMT-2000 system according to the present invention.

5 is a diagram illustrating a format of a direct transmission message received in a core network of an IMT-2000 system according to the present invention.

6 is a flowchart illustrating a retransmission procedure of a service data unit (SDU) in the IMT-2000 system according to the present invention.

7 and 8 are structural diagrams of a retransmission processing structure in a radio link control layer of a transmitting side and a receiving side in the retransmission procedure shown in FIG.

* Description of the symbols for the main parts of the drawings *

21: message identifier 22: message length

23: message compatibility information 24: message processing level

25: direct transfer information

Hereinafter, a configuration and an operation according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

4 is a flowchart illustrating a procedure of transmitting a service data unit (SDU) in an IMT-2000 system according to the present invention, and FIG. 5 illustrates a direct transmission message format received in a core network of the IMT-2000 system according to the present invention. 6 is a flowchart illustrating a retransmission procedure of a service data unit (SDU) in the IMT-2000 system according to the present invention.

In the present invention, the radio interface protocol structure of the radio network control station (RNC) is the same as that of FIG. 1, except that the RRC message is transmitted through a control service access point (SAP) before transmitting the RRC message transmitted from the RRC layer to the SDU. It conveys the importance of the next SDU to be sent.

Therefore, in the proposed format of the direct transmission message according to the present invention, when the RRC layer of the RNC transmits the RRC message to the co-current RRC layer in the control plane, the RRC layer is an important SDU for delivering the SDU to the RLC layer. Direct transfer information including a message identifier 21 and a message length 22 representing a direct transfer message, message compatibility information 23 representing an unacknowledged message, and information transmitted from a core network to a terminal ( In addition to 25), a message processing level 24 is added.

If the message processing level is 0, then the same transmission, retransmission, and SDU abandonment schemes are used. However, if Core Network determines that the message among CC or MM messages to be sent to the terminal via RNC must be delivered, the message processing level is set to 1.

In other words, the CC or MM has information that is used only for information delivery, such as ALERTING, and information that must be delivered, such as Connect, but these contents are not analyzed in RNC. Because it uses (Direct Transfer Message), if it is time to discard SDU, OPERATION was performed to discard SDU regardless of contents of message.

However, as a result, a message received from a core network may be threatened by setting up a call, and even though other SDUs are well delivered, the value of transmission of the remaining SDUs may be meaningless due to the loss of one important SDU. If the processing level is set, the RRC layer sends a primitive to the RLC layer through the control service access point (SAP) to increase the SDU abandonment level (S11). Receiving this primitive, the RLC layer determines that the next SDU delivered is an important message.

In this state, it is determined whether the transmission control is completed (S12).

As a result of determination (S12), if the transmission control is not completed, it is retransmitted and it is determined whether the retransmission control is completed (S13).

As a result of the determination (S13), if retransmission is not completed, the primitive SDU abandonment is performed (Pre_SDU_Discard Operation) to determine whether the primitive SDU abandonment is completed (S14).

Such primitive SDU abandonment is performed to perform retransmission once more (S21 and S22 of FIG. 6), and determine whether retransmission is completed (S23), and if the transfer is not completed after that, the disapproval mode by the quick repeat method. After repeating the transmission (S14), the SDU is abandoned (S16).

7 and 8 are structural diagrams of retransmission processing in a radio link control layer of a transmitting side and a receiving side in the retransmission procedure shown in FIG.

If the RLC layer receiving in acknowledgment mode 31 requests retransmission by the STATUS PDU, the acknowledgment mode processing entity sends a request message containing the sequence number of the PDU that needs to be tuned to the command queue 32. The disapproval mode message handler 33 then polls the command queue 32 and detects the corresponding content to update the grant table checklist table (34).

Then, the disapproval mode processing entity 41 searches (SEARCH) the acknowledgment table checklist before discarding or reporting to the sending RLC layer through the STATUS PDU when the PDU with the wrong sequence number is received during the disapproval message reception (42). If there is a match, the information is transmitted to the information queue 43.

The acknowledgment message handler 44 traverses the information queue 43 and delivers the contents to the acknowledgment processing entity 45. The acknowledgment processing entity 45 retransmits to the sender RLC layer confirming that the retransmission has been delivered in the disapproval mode. Signals that the reception of the SDU is complete.

As described above, the present invention reduces the loss rate of the SDU by changing the retransmission scheme according to the importance of the SDU in the process of delivering the SDU received from the upper layer to the same RNC by the RNC layer of the direct sequence IMT-2000 system, It can improve the success rate of call connection.

Claims (2)

Adding and transmitting an information field according to the importance of the service data unit (SDU) from the radio resource control (RRC) layer to the radio link control (RLC) layer; Updating the revocation level of the service data unit in the radio link control layer according to the information field; Determining whether transmission to the service data unit has been completed; Retransmitting if the transmission is not completed; If the retransmission fails, performing the retransmission once more; And repeating the retransmission in an unauthorized mode by the quick repeat method if the retransmission fails again. The direct transfer message of claim 1, wherein an information field according to importance of a service data unit (SDU) is added and transmitted from the radio resource control (RRC) layer to the radio link control (RLC) layer. Sending a message processing level for determining the importance of the message to direct transmission information including a message identifier indicating a message), a message length, a message compatibility information indicating an unacknowledged message, and information transmitted by a core network to a terminal. A communication operation method of the next generation mobile communication system.