KR20180078538A - Method, apparatus and system for transmitting svc video data in radio communication environment - Google Patents

Abstract

According to an aspect of the present invention, disclosed is a scheduling method for transmitting scalable video coding (SVC) video data in a wireless communications environment. The method comprises the following steps: receiving SVC video data; selecting selectable modulation and coding scheme (MCS) candidates in consideration of a channel quality indicator (CQI) within a range satisfying a threshold image quality for a layer of the SVC video data; and determining a modulation and coding scheme to be applied to each layer of the SVC video data so that user terminals to be transmitted among the modulation and coding scheme candidates can have guarantee for the quality of a threshold image for each layer.

Description

TECHNICAL FIELD [0001] The present invention relates to a scheduling method, apparatus, and system for transmitting SVC video data in a wireless communication environment,

The present invention relates to a scheduling method and apparatus, and more particularly, to a method and apparatus for scheduling video data in a wireless communication environment.

Scalable Video Coding (SVC) is an H.264 international standard and is formed of one BL (Base Layer) and several EL (Enhancement Layer) layers, which can cause a lot of video data traffic. In addition, as multicast services are activated in the future, video multicast services over mobile communication networks are expected to expand. There is a need for research on the resource consumption problem and quality of service (QoS) problems caused by such video multicast service.

Conventionally, when transmitting SVC data in an OFDMA-based system, a modulation and coding scheme (MCS) is selected using a probabilistic model or a subgrouping method to minimize resources, Is proposed. When one modulation is used equally in a multicast group, a cell-edge user (a user located outside the mobile network) will become a bottleneck for video data transmission and receive a smooth service There is a problem that it can not be done.

According to an aspect of the present invention, there is provided a scheduling method for SVC video data transmission in a wireless communication environment for allocating a minimum resource while ensuring video transmission quality using a CQI (Channel Quality Indicator) Device.

According to an aspect of the present invention, there is provided a scheduling method for transmitting Scalable Video Coding (SVC) video data in a wireless communication environment, the method including receiving SVC video data, Selecting a Modulation and Coding Scheme (MCS) candidate that can be selected in consideration of a channel quality indicator (CQI) within a range satisfying a threshold image quality, And determining a modulation and coding scheme to be applied to each layer of the SVC video data so that the transmission target user terminals can guarantee the critical image quality for each layer.

The modulation and coding scheme candidates can be selected in consideration of a condition that the sum of all resources for all layers of the SVC video data should be minimum.

When considering the multicast environment for a plurality of user terminals, the threshold ratio of the number of user terminals satisfying the image quality for the first SVC layer to the total number of user terminals in the multicast environment The modulation and coding scheme candidates can be selected.

The modulation and coding scheme candidates can be selected in consideration of a condition that the ratio of the SVC video quality of the upper layer to the minimum number of users of the first SVC layer is smaller than the number of users satisfying the minimum quality of the first SVC layer .

Wherein the step of determining a modulation and coding scheme to be applied to each layer of the SVC video data among the modulation and coding scheme candidates comprises the steps of decreasing the order of the modulation and coding scheme of the highest order among the modulation and coding scheme candidates, And determining a modulation and coding scheme to be applied to each layer of the SVC video data by determining whether the quality is satisfied.

Determining a modulation and coding scheme to be applied to each layer of the SVC video data among the modulation and coding scheme candidates includes the steps of calculating a resource capable of receiving a SVC video data of a first layer higher than a first threshold, Calculating a resource satisfying the minimum image quality excluding the modulation and coding scheme candidates when the calculated resource is smaller than the available resource as a result of the comparison; And determining a modulation and coding scheme to be applied to each layer of the SVC video data based on the calculated resources.

The determination as to whether the threshold image quality is satisfied can be made by directly simulating the probability that the user terminal successfully receives data of all layers of the SVC video data.

The scheduling method may further include allocating a resource block (RB) in consideration of the selected at least one modulation and coding scheme.

The scheduling method may be used in a multicast environment for transmitting the SVC video data to a plurality of user terminals.

According to another aspect of the present invention, there is provided a scheduling apparatus for SVC (Scalable Video Coding) video data transmission in a wireless communication environment, including a data input unit for receiving SVC video data, (MCS) candidates in consideration of a channel quality indicator (CQI) within a range that satisfies a threshold image quality, and a demodulation section for selecting a candidate for modulation and coding scheme (MCS) And a modulation and coding scheme decision unit for deciding a modulation and coding scheme to be applied to each layer of the SVC video data considering that the transmission target user terminals among the coding scheme candidates are guaranteed to be able to guarantee the critical image quality for each layer .

According to another aspect of the present invention, there is provided a wireless communication system for transmitting SVC video data, the system including: a channel quality indicator for indicating a threshold image quality of a layer of the SVC video data; (MCS) candidates in consideration of the channel quality indicator (CQI) of the selected modulation and coding scheme candidates, and selects a modulation and coding scheme candidate from among the selected modulation and coding scheme candidates, A base station for determining a modulation and coding scheme to be applied to each layer of the SVC video data in consideration of being guaranteed to receive the SVC video data, and a user terminal for transmitting and receiving the SVC video data based on the allocated resources.

According to the scheduling method and apparatus for transmitting SVC video data in the wireless communication environment of the present invention, it is possible to increase the efficiency of resource allocation and reduce the loss rate of video data in the base station, and to use Gaussian ) Hardware can be implemented using the erase method, thereby reducing the complexity of the implementation.

1 is a conceptual diagram illustrating an SVC video multicast transmission system in an LTE-A environment,
2 is a conceptual diagram for explaining a frequency / time domain scheduling method in an LTE-A environment,
FIG. 3 is a conceptual diagram for explaining the flow according to the MAC and PHY steps of the scheduling method for transmitting SVC video data according to an embodiment of the present invention;
4 is a flowchart schematically illustrating a scheduling method for SVC video data transmission according to an embodiment of the present invention.
5 is a detailed flowchart for explaining an MCS determination process of a scheduling method for transmitting SVC video data according to an exemplary embodiment of the present invention;
6 is a block diagram schematically illustrating a scheduling apparatus for transmitting SVC video data according to an embodiment of the present invention.
FIG. 7 is a graph showing a distance to a resource load comparing a conventional method with a scheduling method for transmitting SVC video data according to an embodiment of the present invention,
FIG. 8 is a graph illustrating a distance of a base layer (BL) versus a restoration probability according to an exemplary embodiment of the present invention in comparison with a scheduling method for transmitting SVC video data and a conventional method.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the present invention, the same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

1 is a conceptual diagram illustrating an SVC video multicast transmission system in an LTE-A environment. As shown in FIG. 1, a multicast transmission system according to an embodiment of the present invention may include a base station 120, a multicast group 130, and the like.

Referring to FIG. 1, a base station 120 is a wireless communication equipment for connecting a network and a terminal for wireless communication service, and is a subject of allocating radio resources such as frequency and time. The base station 120 may be referred to as e-UTRAN node-B in the LTE / LTE-A environment and node-B in the 3G communication. The base station may be a base station, an advanced base station (ABS), an HR-BS, a site controller, a base transceiver system (BTS), an access point (AP) But is not limited to, any other type of interfacing device that is capable of operating in an environment.

The base station 120 may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, Lt; RTI ID = 0.0 > RAN. The base station may be configured to transmit and / or receive wireless signals within a particular geographic area, which may be referred to as a cell (not shown).

According to an embodiment of the present invention, the eNB 120 may assume an LTE / LTE-A environment, and the eNB 120 may transmit the layered video data, i.e., the SVC video data 110 in a multicast manner to a plurality of user terminals, And to each user terminal in the multicast group 130. When the same MCS (Modulation and Coding Scheme) is applied to the UEs in the multicast group 130, the eNB 120 causes cell-edge users to become bottlenecks. Therefore, the eNB 120 selects different MCSs And transmit the SVC video data 110. At this time, the minimum image quality according to each layer of the SVC video data 110 to be transmitted can be considered as a factor for selecting the MCS.

The transmitted SVC video data 110 may include a plurality of layers from Layer 1 to Layer L, and each layer has a higher importance as the lower layer. Accordingly, layer 1 (base layer BL) must be decoded so that upper layers (layer 2 or higher) can be decoded based on this. Accordingly, it is desirable that the eNB 120 selects an MCS that maximizes the SVC video quality while minimizing the resource allocation by setting the minimum image quality differently according to the importance of the SVC layer. In addition, the eNB 120 may perform a subgrouping strategy based on the CQI index fed back from the user terminals in the multicast group 130. That is, subgroups of users in the multicast group 130 can be applied to each subgroup. Thereby allowing all user terminals in multicast group 130 to achieve minimum video quality.

The eNB 120 may use RLNC (Random Linear Network Coding) to reduce the loss rate of the multicast video data. RLNC is one of network coding methods. Reducing the loss rate of video data using RLNC increases overall transmission efficiency and enables efficient resource use. In addition, the RLNC can be hardware implemented using the Gaussian elimination method, thereby reducing the complexity of the implementation.

Thus, in one embodiment of the present invention, the eNB 120 uses the RLNC for transmission of the SVC video data 110 and achieves optimization for the resource allocation method.

The multicast group 130 is composed of a plurality of user terminals, and receives the coded SVC video data 110 according to the MCS selected by the eNB 120.

2 is a conceptual diagram for explaining a frequency / time domain scheduling method in an LTE-A environment.

Referring to FIG. 2, the eNB allocates frequency / time domain resources. This is called scheduling. In a two-dimensional domain based on the frequency axis and the time axis, one frame may have 10 ms and one sub-frame may have 1 ms. Also, one slot may have a size of 0.5 ms.

A resource block having one slot and one unit frequency may be composed of 84 resource elements including 12 subcarriers and 7 symbols. In the LTE / LTE-A environment, the eNB can perform scheduling in units of resource blocks configured as described above.

FIG. 3 is a conceptual diagram for explaining the flow according to the MAC and PHY steps of the scheduling method for transmitting SVC video data according to an embodiment of the present invention.

Referring to FIG. 3, the eNB performs a scheduling operation in a MAC area and a PHY area. Upon receiving the original SVC video data V ₁ , V ₂ , ..., V _L in the MAC area, the frequency domain scheduler 310 selects a frequency to minimize the number of resource blocks allocated for transmission. At this time, the eNB considers the size of the fixed resource block, but the capacity of the resource block can be varied by the MCS. That is, according to the MCS having a high coding rate, more information can be transmitted. However, in this case, since the packet loss rate is high, the image quality may be adversely affected. Therefore, although the number of symbols to be transmitted increases with the high coding rate, since the loss rate also increases, it is necessary to provide a minimum line of deterioration in image quality according to the loss rate in consideration of the CQI index.

A table showing the CQI value and the number of coded symbols per resource block according to the MCS scheme is as follows.

[Table 1]

As shown in Table 1, the SINR value according to the MCS varies according to the CQI index. Therefore, it is preferable that the eNB selects the MCS considering the CQI based on this information.

로 정의될 수 있다. 여기서, |·|은 세트의 구성요소의 수를 의미하고, TTI는 전송시간 간격이고, R_l은 l번째 SVC 계층의 비트레이트를 의미하며, SS는 심볼 사이즈를 나타낸다. 모든 심볼을 고정된 사이즈를 가질 수 있다. Referring again to FIG. 3, V _l denotes a set of original video symbols associated with the 1 st SVC layer, and | V _l |

. ≪ / RTI > Here, | · | denotes the number of elements of the set, TTI denotes a transmission time interval, R ₁ denotes a bit rate of the 1 st SVC layer, and SS denotes a symbol size. All symbols can have a fixed size.

According to the embodiment of the present invention, V _l can be defined as follows.

로 표현될 수 있다. 여기서, f_i,l은 난수생성기(RNG: Random Number Generator)를 사용하여 사이즈 q의 한정 필드 GF(q) 너머 무작위로 균일하게 생성된 코딩 계수를 의미한다. Here, v _{i, l} denotes the i-th original symbol associated with the l-th SVC layer. According to an embodiment of the present invention, the MAC layer can be transformed into an RLNC operation. Thus, each original video symbol of each layer is encoded separately. The network coded symbols of the lth SVC layer are a linear combination of all original video symbols in the lth SVC layer. this is

. ≪ / RTI > Here, f _{i, l} means a coding coefficient randomly generated uniformly over a limited field GF (q) of size q using a random number generator (RNG).

을 입력으로 받아, 주파수 도메인 스케줄러(310)는 피드백 받은 CQI를 고려하여 적절한 MCS를 적응적으로 선택한다. 이를 AMC(Adaptive Modulation and Coding)이라 부른다. 주파수 도메인 스케줄러(310)는 AMC 모듈을 포함하고, AMC 모듈은 SVC 비디오 품질을 극대화하면서 리소스 할당을 최소화하는 방향으로 MCS를 선정한다. AMC 모듈은 네트워크 코딩된 심볼들의 전송을 위해 사용되는 최적의 MCS를 할당한다. 주파수 도메인 스케줄러(310)는 할당된 리소스 블록들 및 할당된 MCS에 대한 정보를 PDCCH(Physical Downlink Control Channel)를 통해 사용자 단말로 전송한다. 각 사용자 단말은 PDCCH의 페이로드를 읽고, 적절한 PDSCH(Physical Downlink Shared Channel)의 페이로드로 액세스할 수 있다. That is, depending on the importance,

And the frequency domain scheduler 310 adaptively selects an appropriate MCS considering the feedback CQI. This is called AMC (Adaptive Modulation and Coding). The frequency domain scheduler 310 includes an AMC module, which selects an MCS in a direction that minimizes resource allocation while maximizing SVC video quality. The AMC module allocates an optimal MCS used for transmission of network coded symbols. The frequency domain scheduler 310 transmits information on the allocated resource blocks and the allocated MCS to the user terminal through the Physical Downlink Control Channel (PDCCH). Each user terminal can read the payload of the PDCCH and access the payload of the appropriate PDSCH (Physical Downlink Shared Channel).

4 is a flowchart schematically illustrating a scheduling method for SVC video data transmission according to an embodiment of the present invention.

Referring to FIG. 4, the eNB receives SVC video data to be transmitted (S410). Then, it is preferable to allocate the RB so that the number of blocks of the resource allocated for transmission is minimized while maintaining the SVC video quality.

To this end, the eNB first selects an actually selectable MCS candidate so as to meet the above goal (S420). The candidate selection has the following constraints, and the MCS satisfying the constraint is selected as the candidate MCS. At this time, a selectable MCS candidate is selected in consideration of the channel quality indicator (CQI) within a range satisfying the threshold image quality for the SVC video data layer.

In step S430, a modulation and coding scheme to be applied to each layer of the SVC video data is determined so that the target user terminals can guarantee the critical image quality of each layer among the selected candidates. Hereinafter, steps S420 and S430 will be described in more detail with reference to FIG.

5 is a detailed flowchart illustrating an MCS determination process of a scheduling method for transmitting SVC video data according to an exemplary embodiment of the present invention.

First, the sum of all resources from the first layer (BL) to the first layer is calculated through the following equation (S510).

[Equation 1]

Here, N _l denotes a resource allocated to the l < th > SVC layer, and N denotes a resource available for 1 ms of a subframe. Hereinafter, ml denotes a MCS index assigned to the l-th resource block, and C denotes a set of CQI levels.

The eNB intends to obtain the minimum value of the sum of all resources on the left side of Equation (1). Equation (1) means a condition that the sum of all resources must be smaller than an available resource (| N |).

Then, the following equations are considered as constraints related to Equation (1).

&Quot; (2) "

&Quot; (3) "

&Quot; (4) "

First, considering the Equation (2), the eNB calculates the ratio of users satisfying the quality of the 1 < st > layer SVC video data, U _{TH, l} (S520). In Equation (2), U _{TH, l} is a minimum threshold of the ratio of the number of users that can support the l-th SVC layer to the total number of users receiving the multicasting service. U _{TH, l} can be expressed as a prime number that is greater than or equal to 0 and less than or equal to 1.

과 같이 표현되며, 최소품질을 보장하는 l번째 계층의 전송 성공확률(P_TH,l)보다 높은 전송 성공확률을 갖는 전제(P_k,l≥P_TH,l) 하에 l-1번째 계층 데이터를 받은 사용자들을 U₁이라 표현한다. 따라서 수학식 2는 전체 사용자 중 l번째 계층 SVC 비디오 품질을 만족하는 사용자의 비율을 의미하고, 전체 사용자 중 l번째 계층 SVC 비디오 품질을 만족하는 사용자의 비율이 U_TH,l 이상 되어야 한다는 조건을 의미한다. u _l

Is expressed as follows, the l-1-th layer data the assumption has a high transmission success rate than the transmission success probability of the l-th layer to ensure a minimum quality (P _{TH, l)} (P _{k, l} ≥P _{TH, l)} The received users are expressed as U ₁ . Therefore, Equation (2) means a ratio of users satisfying the l-th layer SVC video quality among all users, and a condition that the ratio of users satisfying the l th layer SVC video quality among all users should be U _{TH, l} do.

Next, it is checked whether the ratio of the number of quality satisfaction users in the (l + 1) th layer is smaller than the ratio in the number of quality satisfied users in the (l) th layer through Equation 3 (S530).

Equation (3) is a mathematical expression that represents a condition that the ratio of the (l + 1) th higher layer SVC video quality satisfactory minimum users should be smaller than the ratio of the minimum quality satisfied users of the (l) th layer. Since it is an upper layer, it is common to set the ratio of the minimum number of users satisfying quality to be small, and the eNB confirms that these conditions are satisfied.

Next, the eNB checks whether the (l + l) th layer transmission probability is smaller than the lth layer transmission probability (S540).

Similarly to Equation (3), Equation (4) also represents a premise that the (l + 1) th layer transmission probability is smaller than the lth layer transmission probability.

Next, a simulation for selecting an optimal MCS is performed in consideration of the following equation (S550).

&Quot; (5) "

Equation (5) expresses the probability of successfully receiving the SVC data of all layers prior to the lth layer by using MCS m _l (meaning a specific MCS). Here, the target error probability of Pe is shown. eNB can be expressed as | N | |, where | P _{k, l} ≥ P _TH, It is necessary to transmit resource blocks.

The eNB can select the best performance MCS for each layer on the basis of the result of simulation through Equation (5) (S560).

As a result, it is the final goal to apply the modulation and the RLNC so that the sum of all resources required under the conditions satisfying the equations (1) to (4) is minimized.

The scheduling method according to the embodiment of the present invention is implemented in the MAC layer and may be applied to SVC multicast transmission.

Programming the above steps for MCS selection can be implemented with the following two main algorithms. That is, it is preferable that steps S520 and 530 of FIG. 5 are performed in algorithm 1, and steps 540 through 560 are performed in algorithm 2. FIG. Algorithm 1 is an algorithm for calculating the maximum MCS, and Algorithm 2 may be an algorithm for calculating the modulation scheme that all users can guarantee the minimum SVC quality considering all of the SVC layers.

Algorithm 1 can be expressed as:

Referring to Algorithm 1, the modulation schemes supported by the physical layer are various. There are performance constraints to consider all these modulation schemes. Therefore, find the maximum value among the modulation schemes that guarantee the minimum QoS, and determine the modulation scheme to be applied to each layer in the modulation schemes below

Algorithm 1 aims at finding the maximum value of MCS under conditions satisfying the above-mentioned Equations (2) and (3). In line 2 of the algorithm 1, it is checked whether all the resources satisfy the equations (2) and (3). Check all 4 or more acceptable CQI levels in line 3. Line 4 collects the CQI values of all users in the multicast group and adds up the sum. When the total value exceeds the threshold value in line 5, the maximum MCS is obtained as the maximum MCS candidate to guarantee the threshold value for the entire resource. The maximum MCS is checked only to the minimum CQI 4, and the following is checked only when the communication environment is poor in Algorithm 2.

The reason for obtaining the maximum MCS through Algorithm 1 is to check only the modulation scheme having the maximum MCS or less by selecting the maximum MCS since the A calculation takes a long time when the algorithm 2 is performed.

The following is algorithm 2.

Algorithm 2 is an algorithm that calculates the modulation scheme that all users can guarantee the minimum SVC quality considering all the SVC layers. Calculate the maximum MCS (| C |) using algorithm 1 based on the CQI value in line 3. From the 4th to 17th lines, the maximum MCS is decremented by one, and the MCS satisfying the minimum quality is selected. Find a resource (| N _l |) that is greater than or equal to the threshold probability (P _{TH, l} ) of probability probability Pk, l? To receive the data of the lth layer so as to be successfully decoded in line 9. If the number of resources required at 10 is less than the number of available resources, that is, if the current communication channel state is not good (for example, the CQI value is 3) Hereinafter, a resource satisfying the minimum quality is calculated. Therefore, in the algorithm 2, a modulation scheme to be used for each SVC layer and an allocated resource can be obtained.

The overall complexity of algorithm 2 is O (L | N || C |). Here, | C | is the total number of MCS indexes. The eNB needs this much time consumption but it guarantees the minimum quality and allocates the minimum resources, so it is not a large delay considering the case of the case of the conventional case of failing after the transmission.

6 is a block diagram schematically illustrating a scheduling apparatus for transmitting SVC video data according to an embodiment of the present invention. 6, a scheduling apparatus 600 according to an exemplary embodiment of the present invention includes a data input unit 610, an MCS candidate selection unit 620, and an MCS determination unit 630.

Referring to FIG. 6, a data input unit 610 receives SVC video data to be transmitted.

The MCS candidate selection unit 620 first selects an actually selectable MCS candidate (S420). For the candidate selection, the MCS satisfying the constraints and the above-mentioned mathematical expressions and constraints are selected as the candidate MCS. At this time, a selectable MCS candidate is selected in consideration of the channel quality indicator (CQI) within a range satisfying the threshold image quality for the SVC video data layer.

The MCS determination unit 630 determines a modulation and coding scheme to be applied to each layer of the SVC video data, so that the target user terminals can guarantee the critical image quality of each layer among the selected candidates.

Simulation result

FIG. 7 is a graph illustrating a distance to a resource load comparing a conventional method with a scheduling method for transmitting SVC video data according to an exemplary embodiment of the present invention.

Referring to FIG. 7, it can be seen that the scheduling method according to an embodiment of the present invention uses the least resources in terms of resource occupancy.

FIG. 8 is a graph illustrating a distance of a base layer (BL) versus a restoration probability according to an exemplary embodiment of the present invention in comparison with a scheduling method for transmitting SVC video data and a conventional method.

Referring to FIG. 8, it can be seen that the performance of the scheduling method according to an embodiment of the present invention is excellent in terms of BL decoding.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions as defined by the following claims It will be understood that various modifications and changes may be made thereto without departing from the spirit and scope of the invention.

Claims (11)

1. A scheduling method for transmitting Scalable Video Coding (SVC) video data in a wireless communication environment,
Receiving SVC video data;
A Modulation and Coding Scheme (MCS) candidate that can be selected in consideration of a channel quality indicator (CQI) within a range satisfying a threshold image quality for the SVC video data layer Selecting step; And
And determining a modulation and coding scheme to be applied to each layer of the SVC video data so that transmission target user terminals among the modulation and coding scheme candidates can be guaranteed a threshold image quality for each layer, A scheduling method for data transmission. The method according to claim 1,
And selecting the modulation and coding scheme candidates in consideration of a condition that a sum of all resources for all layers of the SVC video data should be minimized. The method according to claim 1,
When considering the multicast environment for a plurality of user terminals, the threshold ratio of the number of user terminals satisfying the image quality for the first SVC layer to the total number of user terminals in the multicast environment And selecting the modulation and coding scheme candidates by taking into account the scheduling method of the SVC video data. The method according to claim 1,
A SVC video selecting the modulation and coding scheme candidate considering a condition that a ratio of the SVC video quality of the upper layer to the minimum number of users of the first SVC layer is smaller than the number of users satisfying the minimum quality of the first SVC layer A scheduling method for data transmission. The method of claim 1, wherein the modulating and coding scheme to be applied to each layer of the SVC video data among the modulation and coding scheme candidates includes:
Determining a modulation and coding scheme to be applied to each layer of the SVC video data by determining whether the threshold image quality is satisfied while reducing the order from the modulation and coding scheme of the highest order among the modulation and coding scheme candidates one by one, Scheduling method for SVC video data transmission. The method of claim 1, wherein the modulating and coding scheme to be applied to each layer of the SVC video data among the modulation and coding scheme candidates includes:
Calculating a resource capable of receiving a SVC video data of a first layer at a probability equal to or higher than a first threshold value;
Comparing the calculated resource with a usable resource;
Calculating a resource satisfying the minimum image quality excluding the modulation and coding scheme candidates when the calculated resource is smaller than the available resources as a result of the comparison; And
And determining a modulation and coding scheme for each layer of the SVC video data based on the calculated resource. The method according to claim 1,
Wherein the determination as to whether the threshold image quality is satisfied is performed by directly simulating the probability that data of all layers of the SVC video data are successfully transmitted by the user terminal. The method according to claim 1,
And allocating a resource block (RB) in consideration of the selected at least one modulation and coding scheme. The method according to claim 1,
A method for scheduling SVC video data transmission in a multicast environment in which the SVC video data is transmitted to a plurality of user terminals. 1. A scheduling apparatus for SVC (Scalable Video Coding) video data transmission in a wireless communication environment,
A data input unit for receiving SVC video data;
A Modulation and Coding Scheme (MCS) candidate that can be selected in consideration of a channel quality indicator (CQI) within a range satisfying a threshold image quality for the SVC video data layer Candidate elective government; And
A modulation and coding scheme determining a modulation and coding scheme to be applied to each layer of the SVC video data in consideration of being guaranteed that transmission target user terminals among the modulation and coding scheme candidates can be guaranteed to have a critical image quality per layer Wherein the scheduling method comprises the steps of: A wireless communication system for SVC video data transmission,
A modulation and coding scheme (MCS) candidate which can be selected in consideration of a channel quality indicator (CQI) within a range satisfying a threshold image quality for the SVC video data layer A modulation and coding scheme to be applied to each layer of the SVC video data is determined considering that the transmission target user terminals among the selected modulation and coding scheme candidates are guaranteed to be able to guarantee the threshold image quality for each layer ; And
And a user terminal for transmitting and receiving the SVC video data based on the allocated resources.

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