KR101426959B1 - Method for transmitting voice packet in wireless communication system - Google Patents

Abstract

A method for transmitting a voice packet in a wireless communication system includes: setting a service flow defining a multi service class for a voice packet and a general data packet; setting a transmission path of the voice packet; Performing a session initialization procedure, and transmitting the voice packet through the set transmission path. Since a plurality of service classes can be defined through one DSA-REQ / RSP in the service flow setup process, it is possible to reduce overhead due to DSA-REQ / RSP signaling which must be performed several times for speech packet and RTCP / SIP packet transmission . In addition, since the MAC header optimized for the voice packet in the VoIP service can be adaptively used together with the general MAC header, the MAC header optimized for the voice packet without using the general MAC header for the voice packet is used to waste unnecessary radio resources .

Description

The present invention relates to a method for transmitting voice packets in a wireless communication system,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to wireless communication, and more particularly, to a method for efficiently transmitting voice packets.

The Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard provides techniques and protocols for supporting broadband wireless access. Standardization progressed from 1999 and IEEE 802.16-2001 was approved in 2001. It is based on a single carrier physical layer called 'Wirelssman-SC'. In the IEEE 802.16a standard approved in 2003, 'Wirelssman-OFDM' and 'Wirelssman-OFDMA' were added to the physical layer in addition to 'Wirelssman-SC'. The IEEE 802.16-2004 standard was revised in 2004 after the IEEE 802.16a standard was completed. IEEE 802.16-2004 / Cor1 was completed in 2005 in the form of 'corrigendum' to correct bugs and errors in the IEEE 802.16-2004 standard.

One of the systems considered in the next generation wireless communication system is an Orthogonal Frequency Division Multiplexing (OFDM) system capable of attenuating the inter-symbol interference effect with low complexity. The OFDM converts data symbols input in series into N parallel data symbols, and transmits the data symbols on separate N subcarriers. The subcarriers maintain orthogonality at the frequency dimension. Each orthogonal channel experiences mutually independent frequency selective fading, and the interval of transmitted symbols becomes longer, so that inter-symbol interference can be minimized. Orthogonal frequency division multiple access (OFDMA) refers to a multiple access method in which a part of subcarriers available in a system using OFDM as a modulation scheme is independently provided to each user to realize multiple access. OFDMA provides a frequency resource called a subcarrier to each user, and each frequency resource is provided independently to a plurality of users and is not overlapped with each other. Consequently, frequency resources are allocated mutually exclusively for each user.

The base station schedules radio resources to efficiently use limited radio resources. Scheduling of radio resources is performed in the MAC (Medium Access Control) layer. The scheduling of radio resources should ensure quality of service (QoS). The terminal must connect to a radio network and create a service flow for data transmission. The service flow refers to a connection between a base station and a terminal that provides a specific QoS. The process of creating the service flow is performed through Dynamic Service Addition (DSA). The DSA message is a MAC management message at the MAC layer. The MS and the BS exchange a DSA request (DSA-REQ) message and a DSA response (DSA-RSP) message to define a service class for guaranteeing QoS.

Meanwhile, Voice over Internet Protocol (VoIP) service is a service for transmitting voice packets in real time through an IP network. After the service flow is set up by the DSA-REQ / RSP in the VoIP service, a session initiation procedure between the terminal and the base station is performed by SIP (Session Initiation Protocol), which is a protocol that performs a function of setting a communication path . After the session initialization procedure is performed, the voice packet is transmitted through the RTP (Real Time Transport Protocol) / UDP (User Datagram Protocol) / IP layer and the voice packet transmission is controlled according to the RTCP (Real Time Transport Control Protocol) .

An RTCP packet, a SIP packet, or the like having a size larger than the size of a voice packet may be transmitted periodically or arbitrarily as needed during transmission of a voice packet. The voice packet and the RTCP packet are transmitted with a 6-byte generic MAC header attached to the MAC layer. It is a method to reduce the waste of radio resources and increase the transmission efficiency by using a MAC header optimized for a voice packet of a smaller size than a general MAC header for a voice packet having a small size compared to a general data packet.

However, when setting the service flow through the DSA-REQ / RSP, it is set to designate only one service class. Therefore, the optimized MAC header is used for the voice packet, and the general MAC header is used for the RTCP packet and the SIP packet In this case, the process of setting the service flow through the DSA-REQ / RSP is repeated several times. The delay of the system increases as the process of setting up the service flow is repeated.

There is a need for a method for adaptively using an optimized MAC header for efficiently transmitting voice packets.

SUMMARY OF THE INVENTION The present invention provides a method for efficiently transmitting a voice packet using a MAC header optimized for a voice packet.

A method for transmitting a voice packet in a wireless communication system according to an embodiment of the present invention includes setting a service flow defining a multi service class for a voice packet and a general data packet, Performing a session initialization procedure for setting a transmission path of a packet, and transmitting the voice packet through the set transmission path.

A method for transmitting a voice packet in a wireless communication system according to another aspect of the present invention includes transmitting a request message for requesting generation of a service flow for transmission of a voice packet, Class, a step of receiving a response message to the request message, and a step of transmitting an acknowledgment message to the response message.

Since a plurality of service classes can be defined through one DSA-REQ / RSP in the service flow setup process, overhead due to DSA-REQ / RSP signaling which must be performed several times for speech packet and RTCP / SIP packet transmission is reduced . In addition, since the MAC header optimized for the voice packet in the VoIP service can be adaptively used together with the general MAC header, the MAC header optimized for the voice packet without using the general MAC header for the voice packet is used to waste unnecessary radio resources .

1 is a block diagram illustrating a wireless communication system. Wireless communication systems are widely deployed to provide various communication services such as voice, packet data, and the like.

Referring to FIG. 1, a wireless communication system includes a user equipment (UE) 10 and a base station (BS) 20. The terminal 10 may be fixed or mobile and may be referred to by other terms such as a mobile station (MS), a user terminal (UT), a subscriber station (SS), a wireless device, The base station 20 generally refers to a fixed station that communicates with the terminal 10 and may be referred to in other terms such as a Node-B, a Base Transceiver System (BTS), an Access Point Can be called. One base station 20 may have more than one cell.

Hereinafter, downlink (DL) means communication from the base station 20 to the terminal 10, and uplink (UL) means communication from the terminal 10 to the base station 20. In the downlink, the transmitter may be part of the base station 20 and the receiver may be part of the terminal 10. In the uplink, the transmitter may be part of the terminal 10 and the receiver may be part of the base station 20.

The wireless communication system may be an Orthogonal Frequency Division Multiplexing (OFDM) / Orthogonal Frequency Division Multiple Access (OFDMA) based system. OFDM uses multiple orthogonal subcarriers. OFDM utilizes the orthogonality property between IFFT (inverse fast Fourier transform) and FFT (fast Fourier transform). In the transmitter, data is transmitted by performing IFFT. The receiver performs an FFT on the received signal to recover the original data. The transmitter uses an IFFT to combine multiple subcarriers, and the receiver uses a corresponding FFT to separate multiple subcarriers.

2 is a flowchart illustrating an example of a VoIP service process. The Voice over Internet Protocol (VoIP) service is a service that transmits voice packets in real time through the IP network.

Referring to FIG. 2, a Caller UE requesting transmission of a voice packet transmits a DSA-REQ (Dynamic Service Addition Request) message to a BS (S110). The DSA-REQ message includes a QoS parameter. The QoS parameter is a parameter for ensuring quality of service for transmission of a data packet. The DSA-REQ message may define a service class for a service flow. A service flow refers to a connection between a base station and a terminal. The service class is a scheduling method for guaranteeing QoS. The service class includes Unsolicited Grant Service (UGS), Real-Time Polling Service (rtPS), Non-Real-Time polling Service (nrtPS) and Best Effort Service do. In VoIP service, UGS method supporting real-time service can be applied. The UGS scheme is a scheduling scheme that supports real-time data packets of a certain size periodically generated, such as a VoIP service. The rtPS scheme is a scheduling scheme that supports real-time data packets of various sizes that occur periodically such as a video streaming service.

Table 1 shows an example of parameters associated with scheduling for a service flow.

Type Parameter One SFID 2 CID 3 Service Class Name 4 MBS 5 QoS Parameter Set Type 6 Traffic Priority 7 Maximum Sustained Traffic Rate 8 Maximum Traffic Burst 9 Maximum Reserved Traffic Rate 10 Reserved 11 Uplink Grant Scheduling Type 12 Request / Transmission Policy 13 Tolerated Jitter 14 Maximum Latency 15 Fixed-length versus Variable-length SDU Indicator 16 SDU Size 17 Target SAID 18 ARQ Enable 19 ARQ_WINDOW_SIZE 20 ARQ_RETRY_TIMEOUT - Transmitter Delay 21 ARQ_RETRY_TIMEOUT ?? Receiver Delay 22 ARQ_BLOCK_LIFETIME 23 ARQ_SYNC_LOSS 24 ARQ_DELIVER_IN_ORDER 25 ARQ_PURGE_TIMEOUT 26 ARQ_BLOCK_SIZE 27 RECEIVER_ARQ_ACK_PROCESSING TIME 28 CS Specification 29 Type of Data Delivery Services 30 SDU Inter-arrival Interval 31 Time Base 32 Paging Preference 33 MBS zone identifier assignment 34 Reserved 35 Global Service Class Name 36 Reserved 37 SN Feedback Enabled 38 FSN size 39 CID allocation for Active BSs 40 Unsolicited Grant Interval 41 Unsolicited Polling Interval 42 PDU SN extended subheader for HARQ reordering 43 MBS contents ID 44 HARQ Service Flows 45 Authorization Token 46 HARQ Channel Mapping 47 Packet Error Rate 143 Vendor-Specific QoS Parameter 99-107 Convergence Sublayer Types

The base station transmits a DSA-RSP (Dynamic Service Addition Response) message to the calling terminal as a response to the DSA-REQ message (S120). The BS performs scheduling in a manner that can guarantee QoS and QoS parameters defined in the DSA-REQ message. According to the scheduling result, the DSA-RSP message includes a QoS parameter that can be provided by the base station, one CID (Connection identifier) identifying a connection between the UE and the BS, and one SFID (Service Flow Identifier) identifying the service flow .

The calling terminal transmits a DSA-ACK (Dynamic Service Addition Acknowledgment) message to the base station as a response to the DSA-RSP message (S130). The service flow setting between the terminal and the base station is completed.

After a service flow is created between the terminal and the base station, a session initiation procedure is performed between the calling terminal and the called terminal (S140). The base station of the calling terminal and the base station of the receiving terminal are connected through an IP core network. In the IP core network, the SIP proxy server can relay session initialization. An example of a session initialization procedure through the SIP proxy server will be described later in FIG.

The calling terminal transmits the SIP INVITE message to the receiving terminal through the base station (S141). The SIP INVITE message may include Session Initiation Protocol (SIP), which is a protocol for establishing a communication path, and Session Description Protocol (SDP), which defines the characteristics of packet data transmitted through the established communication path. have. The calling terminal receives the SIP OK message from the receiving terminal through the base station (S142). The SIP OK message may include information modulated for SDP as a response to the SIP INVITE message. The calling terminal transmits a SIP ACK message to the receiving terminal through the base station (S143). The session initialization procedure is completed between the calling terminal and the receiving terminal.

When the session initialization procedure is completed, the calling terminal transmits a voice packet to the base station (S150). The layer structure of voice packets in the calling terminal includes a CODEC layer, a Real Time Transport Protocol (RTP) layer, a UDP (User Datagram Protocol) layer, an IP (Internet Protocol) And PHY (Physical) layer. The voice packet is transmitted through the PHY layer by attaching a generic MAC header according to the service class set in the MAC layer.

During transmission of the voice packet, a Real Time Transport Control Protocol (RTCP) packet may be transmitted for transmission of control information (S160). The RTCP packet may be transmitted periodically or arbitrarily as needed. The RTCP packet is also transmitted through the PHY layer with the general MAC header attached.

Since only one service class is defined in the process of establishing a service flow between a UE and a BS, a voice packet and an RTCP packet are transmitted in units of a MAC PDU (Protocol Data Unit) with a general MAC header of the same size attached thereto. However, voice packets and RTCP packets have different sizes. It is not efficient to use the same size general MAC header.

Table 2 shows an example of the size of a message used in the VoIP service process.

Message Size (byte) SIP INVITE About 600 ~ 800 SIP OK About 300 SIP ACK Approximately 250 RTCP More than 80

When using AMR (adaptive multirate) codec (CODEC) 12.2 kbps, the application layer voice packet size is approximately 33 bytes. Here, an RTP / UDP / IP layer header of about 30 to 40 bytes is added. The RTP / UDP / IP layer header can be compressed to 3 to 4 bytes according to a header compression technique such as RoHC (Robust Header Compression) . The voice packet to which the RTP / UDP / IP layer header is added is transmitted by adding a 6-byte generic MAC header in the MAC layer. The size of the general MAC header is 1.5 to 2 times larger than that of the RTP / UDP / IP layer header.

The size of the voice packet is approximately 33 bytes, while the size of the RTCP packet is more than 80 bytes. It is not efficient to use a general MAC header used for an RTCP packet in a voice packet of a small size. It is effective to use a general MAC header for an RTCP packet and a small size MAC header for a voice packet of a small size.

3 shows an example of a session initiation procedure through a SIP proxy server for a VoIP service.

Referring to FIG. 3, a caller UE and a called UE are connected to an IP core network through their respective base stations. The session initialization procedure can be relayed through the SIP proxy server for the transmission of voice packets in the IP core network.

Here, the identifier of the calling terminal is AA@AA.com, the identifier of the receiving terminal is BB@BB.com, and the receiving terminal is actually located in the domain of BB.com in the domain 8800.BB.com And is registered in a location server.

The calling terminal transmits a SIP INVITE message to the address of BB@BB.com as a SIP proxy server (S210). The SIP proxy server transmits a location request message to the location server to find a terminal corresponding to the address of the SIP INVITE message (S220). The location server notifies the SIP proxy server of the domain address 8800.BB.com where the receiving terminal is actually located (S230). The SIP proxy server transmits the SIP INVITE message to the address of BB@8800.com (S240). The receiving terminal transmits a SIP OK message to the SIP proxy server in response to the SIP INVITE message (S250). The SIP proxy server transmits a SIP OK message to the calling terminal (S260). The calling terminal transmits a SIP ACK message to the SIP proxy server for confirming the session establishment (S270). The SIP proxy server transmits a SIP ACK message to the receiving terminal (S280). The session initialization procedure for transmission of the voice packet is completed.

4 is a block diagram illustrating the structure of a generic MAC header.

Referring to FIG. 4, the general MAC header includes a plurality of fields represented as Table 3. The general MAC header is used to specify the structure of a general data packet and has a size of 6 bytes (= 48 bits).

Table 3 represents fields included in the general MAC header.

Name Length (bit) Description HT One  Header type (shall be zero) EC One Encryption Control
0 = Payload is not encrypted or payload is not included
1 = Payload is encrypted Type 6  Indication of subheaders and special payload types ESF One  Extended Subheader Field CI One  CRC Indicator EKS 2  Encryption Key Sequence Rsv One  Reserved LEN 11  Length. The length in bytes of the MAC PDU CID 16  Connection Identifier HCS 8  Header Check Sequence

A generic MAC header for general data transmission and a MAC signaling header for control signaling are distinguished according to combinations of HT and EC fields. The generic MAC header is appended to the data packet, while the MAC signaling header is not attached to the data packet, i.e., can be transmitted independently without additional payload. {HT, EC} = {0, 0} or {HT, EC} = {0, 1} indicates that the general MAC header is used in the uplink and the downlink, } Or {HT, EC} = {1, 1} indicates that a MAC signaling header for control signaling is used.

5 is a block diagram illustrating a structure of a MAC header according to an embodiment of the present invention. And is a structure of a MAC header optimized for a voice packet having a small size.

Referring to FIG. 5, a MAC header optimized for a voice packet is called a voice packet MAC header. The voice packet MAC header includes EC, EKS, LEN, CID MSB and CID LSB fields. The EC field has a size of 1 bit, the EKS field has 2 bits, the LEN field has 5 bits, the CID MSB field has 8 bits, and the CID LSB field has 8 bits. The voice packet MAC header has a size of 3 bytes. In the voice packet MAC header, an arbitrary field may be added to the general MAC header, if necessary, so that various types of voice packet MAC header can be constructed. The bit value of each field included in the voice packet MAC header is not limited, and the bit value of each field can be changed.

Table 4 shows an example of TLV (Type / Length / Value) of the voice packet MAC header.

Type Length Value Scope [145/146] .x One 0: generic MAC header
1: Voice packet MAC header type 1
2: Voice packet MAC header type 2
3-7: Reserved DSx-REQ
DSx-RSP
DSx-ACK

When the illustrated MAC header is assumed to be a voice packet MAC header type 1, a MAC header in which an arbitrary field is added or removed may be referred to as a voice packet MAC header type 2.

In order to specify the use of the voice packet MAC header in the service flow setting process, parameters for the voice packet MAC header can be added to Table 1. The parameters for the voice packet MAC header can be added to the reserved types in Table 1. [ For example, the parameter 'Voice packet MAC header' may be added to Type 10, Type 34, or Type 36 in Table 1.

If the use of the voice packet MAC header is specified in the service flow setting process, the voice packet MAC header is also applied to the RTCP packet or the SIP packet transmitted together with the voice packet. However, the voice packet MAC header does not support the length of the RTCP packet or the SIP packet having a size of 80 bytes or more since the LEN field is reduced to a size of 5 bits so as to be suitable for a voice packet of a small size.

Hereinafter, a method of specifying the use of the voice packet MAC header and the general MAC header without specifying only one service class in the service flow setting process will be described.

6 is a flowchart illustrating a service flow setting process according to an embodiment of the present invention. And QoS parameters for a plurality of service classes are transmitted as actual field values.

Referring to FIG. 6, the MS transmits a DSA-REQ (Dynamic Service Addition Request) message to a BS to generate a service flow (S310). The DSA-REQ message may define multiple service classes. For example, the service class for transmission of voice packets is referred to as traffic QoS 1 (traffic QoS 1), and the service class for transmission of general data packets such as RTCP packets or SIP packets is referred to as traffic QoS 2 Can be defined. Each service class can be represented by the actual field value of the QoS parameter.

The base station transmits a DSA-RSP (Dynamic Service Addition Response) message to the MS as a response to the DSA-REQ message (S320). The base station performs scheduling in a manner that can guarantee multiple service classes and QoS parameters. According to the scheduling result, QoS parameters, CID (connection identifier) and SFID (Service Flow Identifier) for each service class can be explicitly included in the DSA-RSP message and transmitted. Or the QoS parameters for the main service class and one CID and SFID are included in the DSA-RSP message and the base station can support the multiple service classes in consideration of the packet size for the session and the like.

The MS transmits a DSA-ACK (Dynamic Service Addition Acknowledgment) message to the BS in response to the DSA-RSP message (S330). The service flow setting between the terminal and the base station is completed.

Since a plurality of service classes can be defined through one DSA-REQ / RSP in the service flow setup process, it is possible to reduce overhead due to DSA-REQ / RSP signaling which must be performed several times for speech packet and RTCP / SIP packet transmission . In addition, since the MAC header optimized for the voice packet in the VoIP service can be adaptively used together with the general MAC header, the MAC header optimized for the voice packet without using the general MAC header for the voice packet is used to waste unnecessary radio resources .

Also, in the service flow setting process, the RTCP packet or the SIP packet may not be transmitted according to the service class set for the voice packet, and the RTCP packet or the SIP packet may be transmitted according to the service class suitable for the general data packet. In the case of voice packets, since it is sensitive to delay, it does not support HARQ (Hybrid Automatic Repeat Request) scheme. However, since RTCP packet or SIP packet is not sensitive to delay, HARQ scheme can be applied for reliable data transmission. In this case, when the RTCP / SIP packet is transmitted according to the service class set for the voice packet as in the conventional case, the service flow is different and the HARQ scheme can not be applied. When a plurality of service classes are defined through a single DSA-REQ / RSP according to the proposed method, an RTCP / SIP packet can be transmitted according to a different service flow with a voice packet, so that the HARQ scheme can be applied.

7 is a flowchart illustrating a service flow setting process according to another embodiment of the present invention. And QoS parameters for a plurality of service classes are transmitted in a predetermined representative value.

Referring to FIG. 7, the MS transmits a DSA-REQ message to the BS in order to generate a service flow (S410). The DSA-REQ message may define multiple service classes. For example, the service class for transmission of voice packets is referred to as traffic QoS 1 (traffic QoS 1), and the service class for transmission of general data packets such as RTCP packets or SIP packets is referred to as traffic QoS 2 You can define. At this time, each service class can be represented by a representative value specifying a specific QoS parameter such as QoS Type A and QoS Type B. By specifying a specific QoS parameter with a predetermined representative value, the size of the DSA-REQ message can be reduced.

The base station transmits the DSA-RSP message to the UE as a response to the DSA-REQ message (S420). The DSA-RSP message may explicitly include QoS parameters and CID and SFID for each service class, or may include a QoS parameter for the main service class and one CID and SFID.

The MS transmits a DSA-ACK message to the BS as a response to the DSA-RSP message (S430). The service flow setting between the terminal and the base station is completed.

8 is a flowchart illustrating a service flow setting process according to another embodiment of the present invention. And indicates that a plurality of service classes are automatically applied by indicating the VoIP service.

Referring to FIG. 8, the MS transmits a DSA-REQ message to the BS in order to generate a service flow (S510). The DSA-REQ message does not directly indicate a plurality of service classes, but can indicate that the service type is a VoIP service. Accordingly, the terminal and the base station can automatically apply a plurality of service classes to the VoIP service. It may indicate that a plurality of service classes are applied by including only one QoS parameter in the DSA-REQ message.

The base station transmits the DSA-RSP message to the UE as a response to the DSA-REQ message (S520). The DSA-RSP message may explicitly include QoS parameters and CID and SFID for each service class, or may include a QoS parameter for the main service class and one CID and SFID.

The MS transmits a DSA-ACK message to the BS in response to the DSA-RSP message (S530). The service flow setting between the terminal and the base station is completed.

FIG. 9 is a flowchart illustrating a service flow setting process according to another embodiment of the present invention. This is the case where the base station explicitly represents support for multiple service classes.

Referring to FIG. 9, the MS transmits a DSA-REQ message to the BS in order to generate a service flow (S610). As described in FIGS. 6 to 8, the DSA-REQ message includes QoS parameters for a plurality of service classes as an actual field value or a predetermined representative value, or indicates that a service type is a VoIP service, Can be applied.

The BS transmits the DSA-RSP message to the MS in response to the DSA-REQ message (S620). The base station can explicitly include the QoS parameters, CID and SFID for the multiple service classes in the DSA-RSP message and transmit the DSA-RSP message. For example, the service class for transmission of voice packets is referred to as traffic QoS 1 (traffic QoS 1), and the service class for transmission of general data packets such as RTCP packets or SIP packets is referred to as traffic QoS 2 QoS parameters, CID, and SFID are transmitted for each service class. That is, a plurality of CIDs and SFIDs can be transmitted.

The MS transmits a DSA-ACK message to the BS in response to the DSA-RSP message (S630). The service flow setting between the terminal and the base station is completed.

FIG. 10 is a flowchart illustrating a service flow setting process according to another embodiment of the present invention. And the base station implicitly represents support for multiple service classes.

Referring to FIG. 10, the MS transmits a DSA-REQ message to the BS in order to generate a service flow (S710). As described in FIGS. 6 to 8, the DSA-REQ message includes QoS parameters for a plurality of service classes as an actual field value or a predetermined representative value, or indicates that a service type is a VoIP service, Can be applied.

The base station transmits the DSA-RSP message to the MS as a response to the DSA-REQ message (S720). In the DSA-REQ message, the QoS parameters for the main service class and one CID and SFID are included in the DSA-RSP message, and the BS can support the multi-service class in consideration of the packet size for the session.

The MS transmits a DSA-ACK message to the BS in response to the DSA-RSP message (S730). The service flow setting between the terminal and the base station is completed.

Hereinabove, in the process of setting up the service flow, the UE transmits a DSA-REQ message to the base station to request the generation of the service floor for uplink traffic, and the base station transmits the DSA-RSP message to the UE. The service flow setup process may be a process in which a base station transmits a DSA-REQ message to a mobile station for downlink traffic and a mobile station transmits a DSA-RSP message to a base station. In the service flow setup process for downlink traffic, the transmission direction of the DSA-REQ / RSP message and the voice packet is only in the opposite direction, and the method of applying the multiple service class through one DSA-REQ / RSP can be applied as it is.

All of the functions described above may be performed by a processor such as a microprocessor, a controller, a microcontroller, an application specific integrated circuit (ASIC), etc. according to software or program code or the like coded to perform the function. The design, development and implementation of the above code will be apparent to those skilled in the art based on the description of the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the invention. You will understand. Therefore, it is intended that the present invention covers all embodiments falling within the scope of the following claims, rather than being limited to the above-described embodiments.

1 is a block diagram illustrating a wireless communication system.

2 is a flowchart illustrating an example of a VoIP service process.

3 shows an example of a session initiation procedure through a SIP proxy server for a VoIP service.

4 is a block diagram illustrating the structure of a generic MAC header.

5 is a block diagram illustrating a structure of a MAC header according to an embodiment of the present invention.

6 is a flowchart illustrating a service flow setting process according to an embodiment of the present invention.

7 is a flowchart illustrating a service flow setting process according to another embodiment of the present invention.

8 is a flowchart illustrating a service flow setting process according to another embodiment of the present invention.

FIG. 9 is a flowchart illustrating a service flow setting process according to another embodiment of the present invention.

FIG. 10 is a flowchart illustrating a service flow setting process according to another embodiment of the present invention.

Claims (10)

Setting a service flow defining a multi service class for a voice packet and a general data packet; Performing a session initialization procedure for setting a transmission path of the voice packet; And And transmitting the voice packet through the set transmission path. The method of claim 1, wherein the step of setting the service flow further comprises: Transmitting a request message requesting the setting of the service flow to a base station; And receiving a response message including a plurality of CIDs (Connection Identifiers) from the base station. The method of claim 1, wherein the step of setting the service flow further comprises: Transmitting a request message requesting the setting of the service flow to a base station; Receiving a response message including a plurality of SFIDs (Service Flow Identifiers) from the base station. 2. The method of claim 1, further comprising transmitting a generic data packet for controlling transmission of the voice packet, wherein a generic MAC header is appended to the generic data packet, Wherein a voice packet MAC header having a size smaller than a header is attached to the voice packet. 5. The method of claim 4, wherein the common data packet is a Real Time Transport Control Protocol (RTCP) packet. Transmitting a request message for requesting generation of a service flow for transmitting a voice packet, the request message including a plurality of service classes indicating a plurality of scheduling schemes; Receiving a response message to the request message; And And transmitting an acknowledgment message for the response message. 7. The method of claim 6, wherein the request message includes a quality of service parameter for each of the plurality of scheduling schemes. 7. The method of claim 6, wherein the request message includes a representative value that specifies a quality of service parameter for each of the plurality of scheduling schemes. 7. The method of claim 6, wherein the response message includes a plurality of CIDs and a plurality of SFIDs. The method of claim 6, wherein the response message includes a CID and an SFID for a main service class among the multiple service classes.

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