KR20140011514A - Apparatus and method for transmitting/receiving data in communication system - Google Patents

Abstract

The present invention relates to an apparatus and method for transmitting and receiving data normally by recovering a loss of a data packet in order to improve a multimedia service quality in a wireless communication-based All-Internet Protocol (IP) network. Receiving reception information of a data packet at s; In consideration of the received information, after generating a plurality of frames including data to be transmitted to the receiver, the plurality of frames are included in a payload, the data including a header and the payload Generating a packet; And transmitting the generated data packet to the receiver; The payload includes a mode field including information about the plurality of frames and the plurality of frames; The mode field includes the received information and information indicating the number of the plurality of frames.

Description

Apparatus and method for transmitting / receiving data in communication system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system, and in particular, to recover multimedia packet loss in order to improve multimedia service quality in an all-Internet protocol (IP: Internet protocol) based wireless communication. An apparatus and method for transmitting and receiving data.

In the current communication system, active researches are being conducted to provide users with services of various quality of service (QoS) having a high transmission speed (hereinafter referred to as 'QoS'). In particular, the communication system includes, for example, a wireless local area network (WLAN) system and a mobile communication technology, and with the advent of smart phones. Various multimedia services such as voice, video, and video can be provided.

In addition, as described above, in a communication system that provides a multimedia service through a terminal, various real-time multimedia services are also possible due to the advancement of the network, for example, the expansion of the bandwidth of the network, the improvement of the transmission speed of the network, and the improvement of the terminal performance. However, in spite of the increase of the number of users who want to receive multimedia service and the increase of data volume due to the high quality of voice and video data, the delay of transmission data is still due to the advanced network due to the inherent cause of the IP network which does not guarantee QoS. The loss is occurring.

In addition, the delay and loss in the real-time multimedia service causes the service quality deterioration for the user who wants to receive the multimedia service. In particular, various methods for minimizing data loss, which are the biggest factors of such service quality degradation, have been proposed. For example, a loss recovery method using a forward error correction code, a transmission control method using quality or loss feedback, a congestion avoidance method, etc. This has been proposed. However, these proposed schemes have limitations in data recovery performance and speed in recovering lost data, especially in a communication system that transmits and receives a large amount of data to provide a multimedia service.

Accordingly, there is a need for a method of transmitting and receiving data at high speed and normally by recovering lost data in order to improve the quality of the multimedia service in a communication system providing a multimedia service.

Accordingly, it is an object of the present invention to provide an apparatus and a method for transmitting and receiving data in a communication system.

In addition, another object of the present invention is to provide an apparatus and method for transmitting and receiving data at high speed and normally by recovering a loss of a data packet in order to improve the quality of a multimedia service in a communication system.

An apparatus of the present invention for achieving the above objects, the apparatus for transmitting data in a communication system, comprising: a receiving unit for receiving the reception information of a data packet in the receiver from a receiver; A frame generation unit generating a plurality of frames including data to be transmitted to the receiver in consideration of the received information; A packet generator configured to generate a data packet by including the plurality of frames in a payload; And a transmitter for transmitting the generated data packet to the receiver; The data packet includes a header and the payload; The payload includes a mode field including information about the plurality of frames and the plurality of frames.

According to another aspect of the present invention, there is provided an apparatus for receiving data in a communication system, comprising: a receiving unit receiving a data packet from a transmitter; A confirmation unit for confirming control information included in a header of the data packet and information on a plurality of frames included in a payload of the data packet; A decoder for decoding a plurality of frames included in the payload; A reconstruction unit for reconstructing data transmitted by the transmitter through the decoded plurality of frames; And a transmitter for transmitting the received information of the data packet to the transmitter. The payload includes a mode field including information about the plurality of frames and the plurality of frames.

According to an aspect of the present invention, there is provided a method of transmitting and receiving data in a communication system, the method comprising: receiving received information of a data packet at a receiver from a receiver; In consideration of the received information, after generating a plurality of frames including data to be transmitted to the receiver, the plurality of frames are included in a payload, the data including a header and the payload Generating a packet; And transmitting the generated data packet to the receiver; The payload includes a mode field including information about the plurality of frames and the plurality of frames; The mode field includes the received information and information indicating the number of the plurality of frames.

The present invention recovers the loss of a data packet by adding redundancy data to the main data in a manner that does not require a recovery delay time of the lost data packet of the multimedia service in the communication system, and media between communication terminals. By recovering random or burst packet losses that can occur over wired or wireless networks in real time without retransmission, the quality of the media can be reduced by reducing delays and losses.

1 is a view schematically showing a data packet structure in a communication system according to an embodiment of the present invention.
2 is a diagram schematically illustrating a structure of frames of a data packet in a communication system according to an exemplary embodiment of the present invention.
3 is a diagram schematically illustrating a structure of a transmitting device in a communication system according to an embodiment of the present invention.
4 is a diagram schematically illustrating a structure of a receiving device in a communication system according to an embodiment of the present invention.
5 is a diagram schematically illustrating a process of transmitting a data packet by a transmitting device in a communication system according to an exemplary embodiment of the present invention.
6 is a diagram schematically illustrating a process of receiving a data packet by a receiving device in a communication system according to an exemplary embodiment of the present invention.
7 is a view schematically showing a performance result of a communication system according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, only parts necessary for understanding the operation according to the present invention will be described, and the description of other parts will be omitted so as not to disturb the gist of the present invention.

The present invention proposes an apparatus and method for transmitting and receiving data in a communication system, such as a communication system providing a multimedia service. Here, in the embodiment of the present invention, a communication system including a wireless communication-based All-Internet Protocol (IP) network, for example, a wireless local area network (WLAN) Although a system will be described as an example, the data transmission / reception scheme proposed in the present invention may be applied to other communication systems.

In addition, in an embodiment of the present invention, a communication system for providing a multimedia service recovers a loss of a data packet generated during transmission and reception of multimedia service data for providing a multimedia service, and transmits and receives a large amount of data at high speed and normally. Here, in an embodiment of the present invention, a plurality of frames including data corresponding to the multimedia service are transmitted and received in one data packet. Particularly, in an embodiment of the present invention, a main frame of data corresponding to the multimedia service and a redundancy frame of the main frame are transmitted and received in one data packet, and at this time, reception information of the data packet is received. Add an exclusive OR (XOR) frame of the main frame to the data packet, that is, generate the main frame, the frame, and the XOR frame into one data packet. Send and receive.

In the embodiment of the present invention, when the communication system provides the real-time multimedia service, as described above, the loss of the data packet generated during the transmission and reception of the real-time multimedia service data is recovered, thereby transmitting and receiving a large amount of data at high speed and normally. In this case, a plurality of frames including data corresponding to the real-time multimedia service are transmitted and received in one data packet, for example, a Real-time Transport Protocol (RTP) packet. That is, according to an embodiment of the present invention, the main frame and the redundancy frame of the data corresponding to the real-time multimedia service is transmitted and received in one RTP packet, wherein the main frame, the frame, and the received information of the RTP packet is checked. XOR frame is generated and transmitted as one RTP packet. Then, the data packet transmitted and received by the data transmission and reception apparatus in the communication system according to an embodiment of the present invention will be described in more detail with reference to FIG. 1.

1 is a diagram schematically illustrating a data packet structure in a communication system according to an exemplary embodiment of the present invention. Here, FIG. 1 schematically illustrates a structure of an RTP packet including a plurality of frames including data corresponding to a real-time multimedia service, as described above.

Referring to FIG. 1, the data packet includes a header 100 including control information about the data packet, and a payload 150 including data corresponding to a multimedia service. do. Here, in the header 100 of the data packet, when the receiving device receives the data packet, all the control information necessary for the data recovery of the multimedia service included in the payload 150 of the data packet is received by the receiving device. Included.

Also, as described above, the payload 150 of the data packet includes the plurality of frames when transmitting and receiving a plurality of frames including data corresponding to the multimedia service in one data packet. In particular, the payload 150 of the data packet includes a main frame 160 of data corresponding to the multimedia service, a redundancy frame 165 of the main frame 160, and data received from a receiving device. The XOR frame 170 of the main frame 160 is included according to the received information of the packet. The payload 150 of the data packet includes a mode field 155 including information of frames included in the payload 150 of the data packet. That is, the mode field 155 includes information indicating the number of frames included in the payload 150 as field information.

For example, the transmitting device for transmitting the data packet, after receiving the receiving information of the data packet from the receiving device, confirms the receiving information, the main frame 160 and the redundancy frame 165 in the payload 150 Or the frame included in the payload 150 including the main frame 160, the redundancy frame 165, and the XOR frame 170 in the payload 150. Information about, for example, the number of the included frames is included in the mode field 155. Here, the reception information of the data packet includes data packet loss information of the reception apparatus, that is, a loss ratio, with respect to the data packet received at the reception apparatus, and the reception apparatus has a data packet as shown in FIG. 1. Is transmitted to the transmitting apparatus, in the mode field 155. That is, the mode field 155 transmits a data packet including the mode field 155 as well as information on the number of frames included in the payload 150 as the field information. When the device receives a data packet from the receiving device, the device includes reception information, that is, loss information of the data packet received from the receiving device.

The transmitter checks the reception information included in the mode field 155 of the data packet received from the receiver, and when the loss rate of the data packet is less than a threshold value in the receiver, the payload 150 When the main frame 160 and the redundancy frame 165 is included, and the loss rate of the data packet in the receiving device is greater than a threshold value, the main frame 160 and the payload 150 are included in the payload 150. A redundancy frame 165 and the XOR frame 170 are included and transmitted to the receiving device. In this case, the mode field 155 includes information on the number of frames included in the payload 150 and reception information of the data packet, that is, loss information, in the transmitting apparatus.

In addition, the receiving apparatus confirms control information included in the header 100 of the data packet, and restores data corresponding to the multimedia service included in the payload 150, wherein the header 100 The size of the payload 150 is checked through the check, and the number of frames included in the payload 150 is checked through the mode field 155. Therefore, the receiving apparatus checks the length of the frames included in the payload 150 through the size of the payload 150 and the number of frames. Here, the sizes of the frames included in the payload 150 are the same. The receiving device having received the data packet in this way, like the transmitting device, includes a plurality of frames including data to be transmitted to the transmitting device in the payload 150 and transmits it as one data packet. The number field of the frames included in 150 and the reception information of the data packet, that is, the loss information, are included in the mode field 155 and transmitted by the receiving apparatus. Next, the plurality of frames included in the payload of the data packet transmitted and received by the data transceiving device in the communication system according to an exemplary embodiment of the present invention will be described in more detail with reference to FIG. 2.

2 is a diagram schematically illustrating a structure of frames of a data packet in a communication system according to an exemplary embodiment of the present invention. 2 is a diagram schematically illustrating the structure of a main frame, a redundancy frame, and an XOR frame included in a payload of a data packet.

Referring to FIG. 2, in the communication system, when a transmission device, for example, a terminal transmits data corresponding to a multimedia service in a frame having a sequence number, that is, the transmission device is n (= 7). When transmitting a data packet frame having a first sequence number, for example, an audio frame or a video frame, the transmitting apparatus checks the reception information of the data packet at the receiving apparatus and then includes a plurality of data including data corresponding to the multimedia service. Frames are composed of one data packet and transmitted.

That is, as described above, when the loss rate of the data packet in the receiving device is smaller than the threshold, the transmitting device includes one main frame 210 and a redundancy frame 250 in the payload of the data packet. When the data packet is transmitted and the loss rate of the data packet is larger than the threshold value in the receiving device, the payload includes one main frame 210, a redundancy frame 250, and an XOR frame 280. In this case, the payload mode field includes information on the number of frames included in the payload and reception information of the data packet, that is, loss information.

In more detail, first, the main frame 210 includes a plurality of sequence frames having an arbitrary n (= 7) th sequence number. For example, the nw-3 (= 1) sequence frame 212, nw-2 (= 2) sequence frame 214, nw-1 (= 3) sequence frame 216, nw (= 4) sequence frame 218, n-2 (= 5) sequence frame 220, n-1 (= 6) sequence frame 222, n (= 7) sequence frame 224, n + 1 (= 8) sequence frame 226, n + 2 (= 9) sequence frame 228, And n + 3 (= 10) sequence frame 230.

Here, n (= 1, 2, 3, ... integer), when the communication system provides a real-time multimedia service, means a sequence number of a frame including data sequentially generated for the real-time multimedia service, In the embodiment of the present invention, it is assumed that n = 7 for convenience of description.

And w (= 1, 2, 3, ... integer) is a sequence delay value between the main frame 210 and the redundancy frame 250, the received information of the data packet received by the receiving device through the mode field The value determined correspondingly is determined according to the loss rate of the data packet at the receiving device in order to improve the recovery performance of the lost data packet generated at the time of transmission and reception of the data packet. For example, when the loss rate of the data packet is smaller than the threshold value at the receiving device, w is determined to be smaller than w determined at the time of transmitting and receiving the previous data packet, and when the loss rate of the data packet is larger than the threshold value at the receiving device, W is determined to be larger than w determined at the time of transmission and reception of the previous data packet.

Here, the w is transmitted to the receiving device through the mode field of the payload, and the receiving device, as described above, payload through the information included in the header of the data packet and the mode field of the payload. The size of the frame, the number of frames, and the length of the frames are checked. In particular, the starting point of each frame in the payload is detected through w to decode the frames. That is, the receiving apparatus, based on the size of the payload, the number of frames, the length of the frames, and w, the start point of the main frame, the start point of the redundancy frame, and the start point of the XOR frame in the payload of the data packet By recognizing this, the main frame, the redundancy frame, and the XOR frame are normally decoded to recover the lost data packet, and accordingly, the transmitting device normally recovers the data transmitted.

In addition, the redundancy frame 250 includes a plurality of sequence frames having a sequence delay, that is, w (= 3) of the main frame 210 having an arbitrary n (= 7) th sequence number. -3 (= 1) sequence frame 258, nw-2 (= 2) sequence frame 260, nw-1 (= 3) sequence frame 262, nw (= 4) sequence frame 264, n -2 (= 5) sequence frame 266, n-1 (= 6) sequence frame 268, n (= 7) sequence frame 270, nw-3 (in the main frame 210) = 1) null frames 252, 254, and 256, respectively, corresponding to the sequence frame 212, the nw-2 (= 2) sequence frame 214, and the nw-1 (= 3) sequence frame 216. That is, since the redundancy frame 250 has a sequence delay of w (= 3), sequence frames of the main frame 210 exist after the w (= 3) sequence frame of the main frame 210.

The XOR frame 280 includes frames resulting from performing an XOR operation on the main frame 210 having an arbitrary n (= 7) th sequence number. For example, nw of the main frame 210 is included. An XOR1 frame 282 as a result frame of performing an XOR operation on the -3 (= 1) sequence frame 212, the nw-2 (= 2) sequence frame 214, and the nw-1 (= 3) sequence frame 216. XOR operation on the nw (= 4) sequence frame 218 and the n-2 (= 5) sequence frame 220 and the n-1 (= 6) sequence frame 222 of the main frame 210. The result frame includes the XOR2 frame 284.

Therefore, when the transmitting device transmits a data packet frame having an n (= 7) th sequence number, the payload of the data packet includes the n (= 7) sequence frame 224 of the main frame 210 and redundancy. One data packet is configured by including the nw (= 4) sequence frame 264 of the frame 250 and the XOR1 frame 282 of the XOR frame 280, wherein the three fields described above are included in the mode field of the payload. Information indicating that the frame is included in the payload, that is, information about the number of frames is included. Here, when the transmitter transmits the nth data packet frame, the main frame 210 of the n (= 7) sequence frame 224 and the redundancy frame 250 of the nw (= 4) sequence frame 264 are used. XOR of the nw-3 (= 1) sequence frame 212 and the nw-2 (= 2) sequence frame 214 and the nw-1 (= 3) sequence frame 216 of the main frame 210. As a result of the operation, that is, the XOR frame 280 of the XOR1 282 frame is generated and transmitted as one data packet.

In addition, when the transmitter transmits a data packet frame having an n + 1 (= 8) th sequence number, the n + 1 (= 8) sequence frame 226 of the main frame 210 is included in the payload of the data packet. ) And an n--2 (= 5) sequence frame 266 of the redundancy frame 250 to configure one data packet, wherein the two fields described above are included in the payload in the mode field of the payload. Information indicating the number of frames. In this case, when the transmitter transmits the n + 1 th data packet frame, the main frame 210 of the n + 1 (= 8) sequence frame 226 and the n-2 (= 5) sequence frame 266. The redundancy frame 250 is generated as one data packet and transmitted.

When the transmitting apparatus transmits a data packet frame having an n + 2 (= 9) th sequence number, the payload of the data packet includes an n + 2 (= 9) sequence frame 228 of the main frame 210. ) And the n--1 (= 6) sequence frame 268 of the redundancy frame 250 to configure one data packet, wherein the two fields described above are included in the payload in the mode field of the payload. Information indicating the number of frames. Here, when the transmitter transmits the n + 2 th data packet frame, the main frame 210 of the n + 2 (= 9) sequence frame 228 and the n-1 (= 6) sequence frame 268 The redundancy frame 250 is generated as one data packet and transmitted.

In addition, when the transmitter transmits a data packet frame having an n + 3 (= 10) th sequence number, the payload of the data packet includes an n + 3 (= 10) sequence frame 230 of the main frame 210. ), An n (= 7) sequence frame 270 of the redundancy frame 250, and an XOR2 frame 284 of the XOR frame 280 to form one data packet. Information indicating that the aforementioned three frames are included in the payload, that is, information on the number of frames is included. In this case, when the transmitter transmits the n + 3 th data packet frame, the main frame 210 of the n + 3 (= 10) sequence frame 230 and the n (= 7) sequence frame 270 are separated. Redundancy frame 250, and nw (= 4) sequence frame 218 and n-2 (= 5) sequence frame 220 and n-1 (= 6) sequence frame 222 of main frame 210 The result of performing the XOR operation, that is, the XOR frame 280 of the XOR2 (284) frame is generated as one data packet and transmitted.

In this way, the transmitting apparatus transmits a data packet by including the main frame 210 and the redundancy frame 250 in the payload, or the XOR frame 280 as well as the main frame 210 and the redundancy frame in the payload. In the case of transmitting a data packet including a, the receiving apparatus checks the frames included in the payload and receives data corresponding to the multimedia service transmitted by the transmitting apparatus. As described above, the receiving apparatus confirms the control information on the payload through the header of the data packet, and also checks the number of frames included in the mode field of the payload.

In addition, the receiving apparatus decodes the main frame 210 included in the payload to restore the data transmitted by the transmitting apparatus. In this case, when a predetermined sequence frame is lost in the decoded main frame, the loss is performed. The recovered sequence frame, that is, the lost data packet, through the redundancy frame to restore the data transmitted by the transmitting apparatus. When the sequence frame lost in the main frame is also lost in the redundancy frame, the receiving device restores the sequence frame lost in the main frame and the redundancy frame through an XOR frame and transmits the data transmitted by the transmitting apparatus. Restore it.

For example, in more detail, the receiving apparatus decodes the main frame 210 included in the payload to restore data transmitted by the transmitting apparatus, and thus, nw-3 of the main frame 210. (= 1) When the sequence frame 212 is lost, the redundancy frame 250 is decoded to check the nw-3 (= 1) sequence frame 212 of the redundancy frame 250, and the redundancy frame ( Restore nw-3 (= 1) sequence frame 212 of the lost main frame 210 to nw-3 (= 1) sequence frame 212 of 250 to restore the data transmitted by the transmitting device. do. In this case, when not only the nw-3 (= 1) sequence frame 212 of the main frame 210 but also the nw-3 (= 1) sequence frame 212 of the redundancy frame 250 are also lost, the XOR Decode the frame 280 to identify the XOR1 frame 282 of the XOR frame 280, and the nw-3 (= 1) sequence frame 212 and nw-2 (= 2) of the main frame 210. Nw-3 (= 1) sequence of the lost main frame 210 through the XOR1 frame 282 as a result of performing the XOR operation on the sequence frame 214 and the nw-1 (= 3) sequence frame 216 The frame 212 is recovered to restore the data transmitted by the transmitting apparatus. Here, the nw-3 (= 1) sequence frame 212 of the lost main frame 210 includes the nw-2 (= 2) sequence frame 214 and nw-1 (=) of the main frame 210. 3) The sequence frame 216 and the XOR1 frame 282 perform an XOR operation to recover the nw-3 (= 1) sequence frame 212 of the lost main frame 210.

In addition, the decoded main frame 210 is input to a jitter buffer of a restoration unit included in a receiving device, and the decoded redundancy frame 250 and the decoded XOR frame 280 are recovery of the restoration unit. A sequence frame entered in a recovery buffer and lost in the decoded main frame 210 as described above is recovered through the decoded redundancy frame 250 or the decoded XOR frame 280, The transmission data contained in the payload is normally restored. In addition, the reception apparatus includes the reception information of the data packet corresponding to the loss of the data packet and recovery of the lost data packet as described above, that is, the loss information of the data packet in the payload of the data packet for transmitting to the transmission apparatus. It is included in the mode field and transmitted to the transmitting apparatus. Next, an apparatus for transmitting the data packet as described above in the communication system according to an exemplary embodiment of the present invention will be described in more detail with reference to FIG. 3.

3 is a diagram schematically illustrating a structure of a transmitting device in a communication system according to an exemplary embodiment of the present invention. 3 is a diagram schematically illustrating an apparatus for transmitting the plurality of frames in one data packet by including data corresponding to a multimedia service in the plurality of frames as described with reference to FIGS. 1 and 2.

Referring to FIG. 3, the transmitter 300 checks the receiver 310 to receive data packet transmitted by the receiver and received information of the data packet from the receiver, and confirms the received information. A frame generator 320 for generating a plurality of frames included in the payload of the data packet, a packet generator 330 for generating one data packet by including the generated plurality of frames in the payload, and the generation And a transmitter 340 for transmitting the data packet to the receiver.

In more detail, the receiving unit 310 receives the data packet from the receiving device, and also receives information of the data packet in the receiving device through a mode field included in the payload of the received data packet, In other words, the loss information of the data packet is received.

The frame generation unit 320 generates a plurality of frames including data to be transmitted to the receiving device, that is, data corresponding to a multimedia service. In this case, the frame generating unit 320 considers loss information of the data packet in the receiving device. Determine the number and w of frames, and generate a main frame and a redundancy frame, or generate an XOR frame as well as the main frame and the redundancy frame, depending on the number and w of the frames thus determined.

In addition, the packet generator 330 generates a data packet by including a plurality of frames generated by the frame generator 320 in a payload, wherein the payload is included in the payload in a mode field of the payload. Include information about the frames, in particular information indicating the number of the frames. The payload of the data packet includes the main frame and the redundancy frame, or includes the main frame, the redundancy frame, and the XOR frame according to the loss information of the data packet in the receiving apparatus.

In addition, the transmitter 340 transmits the data packet generated by the packet generator 330 to the receiver. Here, the structure of the data packet transmitted to the receiving device, and the frames included in the payload of the data packet, that is, the structure of the XOR frame as well as the main frame and the redundancy frame, and a plurality of at the transmitting device 300 Generation and transmission operations of the frames and the data packet have been described in detail with reference to FIGS. 1 and 2, and thus detailed operations thereof will be omitted. Next, the apparatus for receiving the data packet as described above in the communication system according to an exemplary embodiment of the present invention will be described in more detail with reference to FIG. 4.

4 is a diagram schematically illustrating a structure of a receiving apparatus in a communication system according to an exemplary embodiment of the present invention. Here, FIG. 4 schematically illustrates an apparatus for receiving the data packet when data corresponding to the multimedia service is transmitted in one data packet as included in the plurality of frames as described with reference to FIGS. 1 and 2. Drawing.

Referring to FIG. 4, the receiving device 400 includes a receiving unit 410 for receiving a data packet transmitted by a transmitting device, control information included in a header of the received data packet, and a payload of the received data packet. A confirmation unit 420 for confirming field information included in a mode field of the decoder, a decoder 430 for decoding a plurality of frames included in the payload, and a recovery apparatus for recovering a frame lost from the decoded frames. A restorer 440 for restoring the transmitted data, and a transmitter 450 for transmitting the received information of the data packet corresponding to the lost frame, that is, the lost information of the data packet, to the transmitter.

More specifically, the receiver 410 receives the data packet transmitted by the transmitter, as described with reference to FIG. 3. That is, the receiver 410 receives a data packet including data corresponding to a multimedia service, the data packet includes a header and a payload, and the payload includes a plurality of mode fields and the data. Frames are included.

The identification unit 420 confirms control information included in the header, and also includes field information included in a mode field of the payload, that is, information on a plurality of frames included in the payload. For example, information indicating the number of frames and reception information of a data packet in the transmitting apparatus are checked. That is, the identification unit 420, based on the information included in the header and the information contained in the mode field, the size of the payload, the number of frames, the length of the frames, and the frame in the payload Check their starting point.

In addition, the decoder 430 decodes the frames included in the payload based on the information confirmed by the identification unit 420. Here, the decoder 430 decodes the main frame as described above in the frames included in the payload, and then decodes the redundancy frame when there is a lost sequence frame in the decoded main frame. Redundancy frames that are decoded also decode the XOR frame if the sequence frame is lost. The decoded frames are input to the jitter buffer and the recovery buffer of the recovery unit 440.

In addition, the reconstructor 440 checks the sequence frame lost in the decoded main frame, and if the lost sequence frame exists, converts the sequence frame corresponding to the lost sequence frame from the decoded redundancy frame. Recover the lost sequence frame, and if the lost sequence frame is also lost in the decoded redundancy frame, recovers the lost sequence frame through the XOR frame, thereby recovering the data transmitted from the transmitting apparatus, that is, the multimedia service. Restore the corresponding data.

The transmitting unit 450 transmits a data packet that the receiving device 400 transmits to the transmitting device. In this case, the transmitting unit 450 transmits the data packet to the mode field of the payload of the transmitted data packet. It includes the received information of the data packet, that is, the data packet loss and the loss information of the data packet corresponding to the recovery of the lost data packet in the receiving apparatus 400 as described above, and transmits it. Here, the structure of the data packet received from the transmitting apparatus, and the frames included in the payload of the data packet, that is, the structure of the XOR frame as well as the main frame and the redundancy frame, and a plurality of at the receiving apparatus 400 Receiving operations of the frames and the data packet have been described in detail with reference to FIGS. 1 and 2, and thus detailed operations thereof will be omitted. Next, an operation of transmitting the data packet as described above in the communication system according to an exemplary embodiment of the present invention will be described in more detail with reference to FIG. 5.

5 is a diagram schematically illustrating a process of transmitting a data packet by a transmitting device in a communication system according to an exemplary embodiment of the present invention.

Referring to FIG. 5, in step 510, the transmitting apparatus checks data packet received from the receiving apparatus and reception information of the data packet at the receiving apparatus. Here, the reception information of the data packet at the reception device, that is, the loss information of the data packet is checked through the mode field included in the payload of the data packet received from the reception device.

Next, in step 520, a plurality of frames including data to be transmitted to the receiving device, that is, data corresponding to a multimedia service are generated. In this case, the number of frames and the number of frames are considered in consideration of loss information of the data packet in the receiving device. Determine w and generate a main frame and a redundancy frame according to the number and w of the frames thus determined, or generate an XOR frame as well as the main frame and the redundancy frame.

In operation 530, the generated plurality of frames are included in the payload to generate a data packet. In this case, information about the frames included in the payload, in particular, the number of the frames, is included in a mode field of the payload. Include indicative information. The payload of the data packet includes the main frame and the redundancy frame, or includes the main frame, the redundancy frame, and the XOR frame according to the loss information of the data packet in the receiving apparatus.

In operation 540, the generated data packet is transmitted to the receiving device. Here, the structure of the data packet transmitted to the receiving device, and the frames included in the payload of the data packet, that is, the structure of the XOR frame as well as the main frame and the redundancy frame, and the plurality of frames and data packet Since the generation and transmission operations have been described in detail above, detailed description thereof will be omitted herein. Next, an operation of receiving the data packet as described above in the communication system according to an exemplary embodiment of the present invention will be described in more detail with reference to FIG. 6.

6 is a diagram schematically illustrating a process of receiving a data packet by a receiving device in a communication system according to an exemplary embodiment of the present invention.

Referring to FIG. 6, in step 610, the receiving device receives a data packet transmitted by a transmitting device, that is, a data packet including data corresponding to a multimedia service. The data packet includes a header and a payload, and the payload includes a mode field and a plurality of frames including the data.

Next, in step 620, the control information included in the header of the data packet is checked, and the field information included in the mode field of the payload, that is, the information on the plurality of frames included in the payload. For example, information indicating the number of frames and reception information of a data packet in the transmitting apparatus are checked. That is, the size of the payload, the number of frames, the length of the frames, and the starting point of the frames in the payload are identified through the information included in the header and the information included in the mode field.

In operation 630, the frames included in the payload are decoded based on the identified information. Here, after decoding the main frame as described above in the frames included in the payload, if there is a lost sequence frame in the decoded main frame, the redundancy frame is decoded, and the decoded redundancy frame also includes a sequence frame If lost, decode the XOR frame.

Next, in step 640, the lost sequence frame is identified in the decoded main frame, and if the lost sequence frame exists, the lost sequence is changed from the decoded redundancy frame to a sequence frame corresponding to the lost sequence frame. And recover the lost sequence frame through the XOR frame when the lost sequence frame is also lost in the decoded redundancy frame, thereby transmitting data transmitted by the transmitting apparatus, that is, data corresponding to the multimedia service. Restore it.

Here, the reception information of the data packet at the receiving device, that is, the loss information of the data packet corresponding to the loss of the data packet at the receiving device and recovery of the lost data packet as described above, is sent to the data packet to the transmitting device. At the time of transmission, it transmits to the said transmission apparatus, At this time, the loss information of the said data packet is contained in the mode field of the payload of the data packet transmitted to the said transmission apparatus. In addition, the structure of the data packet received from the transmitting apparatus, and the frames included in the payload of the data packet, that is, the structure of the XOR frame as well as the main frame and the redundancy frame, and receiving a plurality of frames and data packets Since the operation has been described in detail above, a detailed operation thereof will be omitted.

As described above, in the communication system according to an exemplary embodiment of the present invention, as described above, a plurality of frames including data corresponding to a multimedia service are transmitted and received in one data packet, and the payload of the data packet is included in the receiving apparatus. The main frame and the redundancy frame are included, or the main frame, the redundancy frame, and the XOR frame are included according to the loss information of the data packet of the information packet. The information indicating the number of frames is included in a mode field of the payload, and the information on the payload is included in a header of the data packet.

In addition, in the communication system according to an embodiment of the present invention, after receiving the data packet as described above, after decoding the main frame from the frames included in the payload of the data packet, the decoded main frame is lost Decoded redundancy frames if there is a sequence frame present, and the decoded redundancy frames also decode XOR frames if sequence frames are lost. Identify the lost sequence frame in the decoded main frame, and recover the lost sequence frame from the decoded redundancy frame to the sequence frame corresponding to the lost sequence frame if the lost sequence frame exists; When the lost sequence frame is also lost in the decoded redundancy frame, the lost sequence frame is recovered through the XOR frame to restore data transmitted by the transmitting apparatus, that is, data corresponding to the multimedia service.

Accordingly, in a communication system according to an exemplary embodiment of the present invention, methods proposed to minimize existing data loss, for example, a loss recovery method using a forward error correction code, a transmission control method using quality or loss feedback, and congestion Compared with communication systems using the avoidance method, the packet loss rate is significantly lowered, thereby improving the performance of transmitting and receiving data, thereby transmitting and receiving large amounts of data normally. Referring to FIG. 7, the transmission / reception performance 710 of the communication system according to the embodiment of the present invention is compared with the transmission / reception performance 720, 730, and 740 of conventional communication systems. With the highest quality of service and the highest quality of service at the same packet loss rate, a communication system according to an embodiment of the present invention can normally transmit and receive a large amount of data having a higher QoS level than conventional communication systems. In addition, it has the smallest packet loss rate when transmitting and receiving the same data packet as the conventional communication systems (where FIG. 7 schematically shows the performance results of the communication system according to an embodiment of the present invention). Drawing.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be determined by the scope of the appended claims, as well as the appended claims.

Claims (20)

An apparatus for transmitting data in a communication system,
A receiving unit which receives reception information of a data packet at the receiver from a receiver;
A frame generation unit generating a plurality of frames including data to be transmitted to the receiver in consideration of the received information;
A packet generator configured to generate a data packet by including the plurality of frames in a payload; And
A transmitting unit for transmitting the generated data packet to the receiver;
The data packet includes a header and the payload;
The payload is a data field, characterized in that it comprises a mode field (mode field) including information on the plurality of frames and the plurality of frames.
The method of claim 1,
The mode field includes the reception information and information indicating the number of the plurality of frames.
3. The method of claim 2,
The frame generator determines a loss ratio of the data packet through the received information, and includes a main frame including a plurality of sequence frames corresponding to the data, and a redundancy frame of the main frame. And an exclusive OR (XOR) frame of the main frame.
The method of claim 3,
And the packet generation unit generates the data packet by including the main frame and the redundancy frame in the payload when the loss rate is smaller than a threshold value.
The method of claim 3,
The packet generation unit generates a data packet by including the main frame, the redundancy frame, and the XOR frame in the payload when the loss rate is greater than a threshold.
The method of claim 3,
And the frame generation unit generates the redundancy frame in which the sequence frames of the main frame are delayed in sequence according to the loss rate.
The method according to claim 6,
And all the fields include sequence delay information of the sequence frames in the redundancy frame.
The method of claim 3,
And the frame generation unit generates the XOR frame including frames as a result of performing an XOR operation on predetermined sequence frames adjacent to the sequence frames of the main frame according to the loss rate.
An apparatus for receiving data in a communication system,
A receiver which receives a data packet from a transmitter;
A confirmation unit for confirming control information included in a header of the data packet and information on a plurality of frames included in a payload of the data packet;
A decoder for decoding a plurality of frames included in the payload;
A decompressor for restoring data transmitted by the transmitter through the decoded plurality of frames; And
A transmitter for transmitting the received information of the data packet to the transmitter;
The payload may include a mode field including information about the plurality of frames and the plurality of frames.
10. The method of claim 9,
The mode field includes the reception information and information indicating the number of the plurality of frames.
The method of claim 10,
The identification unit, through the header and the mode field, characterized in that for confirming the size of the payload, the length of each of the plurality of frames, and each starting point of the plurality of frames in the payload Receiving device.
The method of claim 10,
The decoder, after decoding a main frame including a plurality of sequence frames corresponding to the data in the plurality of frames, when there is a sequence frame lost in the sequence frames of the decoded main frame, And decoding a redundancy frame of the main frame in the plurality of frames.
The method of claim 12,
The recovery unit recovers the lost sequence frame from the decoded redundancy frame to a sequence frame corresponding to the lost sequence frame.
The method of claim 12,
The decoder is configured to decode an exclusive OR (XOR) frame of the main frame when a sequence frame corresponding to the lost sequence frame is lost in the decoded redundancy frame.
15. The method of claim 14,
The reconstructor may perform an XOR operation on an XOR operation result frame corresponding to the lost sequence frame in the decoded XOR frame and sequence sequences adjacent to the lost sequence frame in the decoded main frame to perform the lost sequence frame. Data receiving apparatus, characterized in that for recovering.
In the communication system for transmitting and receiving data,
Receiving reception information of a data packet at the receiver from a receiver;
In consideration of the received information, after generating a plurality of frames including data to be transmitted to the receiver, the plurality of frames are included in a payload, the data including a header and the payload Generating a packet; And
Transmitting the generated data packet to the receiver;
The payload includes a mode field including information about the plurality of frames and the plurality of frames;
The mode field, the data transmission and reception method, characterized in that it includes information indicating the number of the plurality of frames.
17. The method of claim 16,
Generating a main frame including a plurality of sequence frames corresponding to the data by checking a loss ratio of the data packet through the received information;
Generating a redundancy frame in which the sequence frames of the main frame are delayed in sequence according to the loss rate; And
And generating an XOR frame including frames as a result of performing an exclusive OR between the adjacent adjacent sequence frames in the sequence frames of the main frame according to the loss rate. How to send and receive data.
The method of claim 17, wherein the generating step,
If the loss rate is less than a threshold, include the main frame and the redundancy frame in the payload to generate a data packet;
And when the loss rate is greater than a threshold value, generating the data packet by including the main frame, the redundancy frame, and the XOR frame in the payload.
17. The method of claim 16,
Decoding a main frame including a plurality of sequence frames corresponding to the data in the plurality of frames;
If there is a lost sequence frame in the sequence frames of the decoded main frame, decoding a redundancy frame of the main frame in the plurality of frames; And
Decoding an exclusive OR (XOR) frame of the main frame when a sequence frame corresponding to the lost sequence frame is lost in the decoded redundancy frame. .
20. The method of claim 19,
Recovering the lost sequence frame from the decoded redundancy frame to a sequence frame corresponding to the lost sequence frame; And
Recovering the lost sequence frame by performing an XOR operation between an XOR operation result frame corresponding to the lost sequence frame in the decoded XOR frame and sequence sequences adjacent to the lost sequence frame in the decoded main frame. Data transmission and reception method characterized in that it further comprises.

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