KR20170078303A - Base station and control method thereof - Google Patents

Abstract

The present invention proposes an operation method of a base station apparatus and a base station apparatus capable of efficiently improving a phenomenon in which a frequency efficiency is reduced in proportion to the number of terminals that are objects of a multicast service in providing a multicast service.

Description

TECHNICAL FIELD [0001] The present invention relates to a base station apparatus and a base station apparatus,

The present invention relates to a base station apparatus and an operation method of a base station apparatus, and more particularly, to a base station apparatus and a base station apparatus capable of efficiently improving the frequency efficiency in proportion to the number of terminals, which are targets of a multicast service, And more particularly, to a base station apparatus and a base station apparatus.

In the case of a multicast service (one-to-many communication) in which the same data is transmitted to a plurality of terminals (users) such as a broadcast service (MBMS), since the same resources are allocated to the plurality of terminals and the same data is transmitted, The efficiency is very high in terms of frequency.

One of the technologies for providing such a multicast service is SC-PTM (Single-Cell Point-to-Multipoint).

SC-PTM can provide a multicast service on a per-base-station basis, and the greatest advantage compared with other technologies that provide a multicast service is that the modulation and coding scheme (MCS) can be dynamically Setting / adjusting.

That is, since the SC-PTM receives the feedback on the channel state from the UE, the SC-PTM can set a MCS level that can be decoded by all the UEs to which the multicast service is provided and adjust the MCS level dynamically to obtain a relatively high performance .

When setting the MCS level, the SC-PTM adopts a method of setting the MCS level with a focus on the terminal having the worst channel status among all the terminals (users) to which the multicast service is provided.

However, the greater the number of terminals to which multicast service is provided, the higher the probability that the channel state of the terminal having the worst channel state with respect to the average channel state of the terminals becomes larger.

The MCS setting method of the existing SC-PTM that sets the MCS level with the focus on the terminal with the worst channel state is as follows. As the gap of the channel state of the terminal with the worst channel state compared to the average channel state becomes larger The more inefficient.

This is because as the lower MCS level is set, the base station must allocate more frequency bands in order to satisfy the target rate. However, other terminals with good channel status can receive data at a higher MCS level, This is because many frequency bands must be allocated until data is received at the MCS level.

In the present invention, as described above, as the gap between the channel states of the terminal having the worst channel state compared to the average channel state is increased (the number of terminals is increased), the frequency efficiency is lowered. And the frequency efficiency is reduced in proportion to the number.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a multicast service in which efficiency of frequency efficiency is reduced in proportion to the number of terminals to which a multicast service is provided, And an operation method of the base station apparatus and the base station apparatus.

In order to achieve the above object, a base station apparatus according to a first aspect of the present invention includes: a grouping unit for grouping a plurality of terminals into a first group and a remaining group to a second group in all terminals to which a multicast service is provided; A frequency band role part allocating an additional frequency band to the first group; A data processing scheme setting unit for setting data processing schemes differently in each of the fundamental frequency band for the multicast service and the additional frequency band; And providing the multicast service to the entire terminal based on a data processing method set in the basic frequency band through the basic frequency band, and a data processing method set in the additional frequency band through the additional frequency band And a service providing unit for providing the multicast service to the terminal in the first group based on the multicast service.

The grouping unit may group some UEs whose channel quality information is less than or equal to a preset threshold value into the first group based on the channel quality information of the basic frequency band received from the entire UE.

Preferably, the data processing mode setting unit sets the data processing mode setting unit to select a terminal having the smallest channel quality information value among the terminals in the first group based on the channel quality information of the additional frequency band received from the terminal in the first group The data processing method can be set in the additional frequency band.

Preferably, the data processing mode setting unit sets the data processing mode setting unit to select a terminal having the smallest channel quality value among the terminals in the second group based on the channel quality information of the basic frequency band received from the terminal in the second group, The data processing method can be set in the basic frequency band.

Preferably, the data processing mode setting unit adjusts the data processing method in the additional frequency band based on the feedback information related to the additional frequency band received from the terminal in the first group, The data processing method can be adjusted in the basic frequency band based on the basic frequency band related feedback information.

Advantageously, the grouping unit moves a specific terminal in the first group to the second group, and moves a specific terminal in the second group to the first group.

The specific terminal in the first group may be a terminal that satisfies a target rate as a result of decoding data of the multicast service using only the basic frequency band without using the additional frequency band.

Preferably, the specific terminal in the second group may be a terminal whose channel quality value measured in the basic frequency band falls below a preset threshold value.

According to a second aspect of the present invention, there is provided a method of operating a base station apparatus, the method comprising: grouping a plurality of terminals into a first group and a remaining group to a second group in all terminals to which a multicast service is provided; A frequency band allocation step of allocating an additional frequency band to the first group; A data processing method setting step of setting a data processing method in each of the basic frequency band and the additional frequency band for the multicast service differently; And providing the multicast service to the entire terminal based on a data processing method set in the basic frequency band through the basic frequency band, and a data processing method set in the additional frequency band through the additional frequency band And providing the multicast service to the terminals in the first group based on the multicast service.

Preferably, the grouping step may include grouping, into the first group, a plurality of UEs whose channel quality information is less than or equal to a preset threshold based on the channel quality information of the basic frequency band received from the entire UE .

Preferably, the data processing mode setting step includes a step of setting, based on the channel quality information of the basic frequency band received from the terminal in the second group, a terminal having the smallest channel quality information value among the terminals in the second group And the channel quality information of the terminal in the first group is set to a minimum value based on the channel quality information of the additional frequency band received from the terminal in the first group, The data processing method can be set in the additional frequency band based on the terminal.

Preferably, the data processing method is adjusted in the additional frequency band based on the additional frequency band related feedback information received from the terminal in the first group, and the basic frequency band related feedback And adjusting the data processing method in the basic frequency band based on the information.

Advantageously, a particular terminal in the first group may be moved to the second group, and a particular terminal in the second group may be moved to the first group.

Preferably, the specific terminal in the first group is a terminal satisfying a target rate as a result of decoding the data of the multicast service using only the basic frequency band without using the additional frequency band, A specific terminal in the second group may be a terminal whose channel quality value measured in the basic frequency band falls below a preset threshold value.

Thus, according to the operation method of the base station apparatus and the base station apparatus of the present invention, the effect of reducing the frequency efficiency in proportion to the number of terminals to which the multicast service is provided in providing the multicast service can be efficiently improved .

1 is a configuration diagram illustrating a communication system including a base station apparatus according to a preferred embodiment of the present invention.
2 is a block diagram illustrating a configuration of a base station apparatus according to a preferred embodiment of the present invention.
3 is a flowchart illustrating an operation method of a base station apparatus according to a preferred embodiment of the present invention.
4 is an exemplary diagram showing a frequency band and a data processing method (MCS level) allocated and set according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a diagram illustrating a communication system including a base station apparatus according to a preferred embodiment of the present invention.

1, a communication system including a base station apparatus according to a preferred embodiment of the present invention is connected to the base station apparatus 100 and the base station apparatus 100 according to the present invention and is provided from the base station apparatus 100 And a plurality of terminals (1, 2, 3 ... 10) using a multicast service.

The multicast service refers to a one-to-many communication method in which the same resource (frequency band) is allocated to a plurality of terminals (users) and the same data is transmitted, such as a broadcast service (MBMS).

Accordingly, the base station apparatus 100 according to the present invention is preferably a base station capable of providing a multicast service, among other communication services.

The base station apparatus 100 of the present invention further includes a single-cell point-to-point (SC-PTM) system 100 capable of dynamically setting / adjusting a data processing scheme, i.e., a modulation and coding scheme (MCS) It is desirable to provide a multicast service based on Multipoint.

Hereinafter, the data processing method and the MCS have the same meaning and will be used in accordance with the description.

1, it is assumed that a plurality of terminals (1, 2, 3,... 10) are objects of provision of a multicast service provided by the base station apparatus 100. FIG.

On the other hand, since the SC-PTM receives the feedback on the channel state from the UE, the SC-PTM sets an MCS level that can be decoded by all the UEs (1, 2, 3 ... 10) And relatively high performance can be obtained by adjusting the MCS level.

Referring to FIG. 1, a method of setting an MCS level in an existing SC-PTM will be described. In the conventional SC-PTM, Sets the MCS level with the focus on the worst terminal.

For example, when it is assumed that the channel state of the terminal 1 is the worst, the existing SC-PTM uses the data processing system, that is, the MCS Quot; is set.

However, the greater the number of terminals to which multicast service is provided, the higher the probability that the channel state of the terminal having the worst channel state with respect to the average channel state of the terminals becomes larger.

The existing MCS setting method of the existing SC-PTM for setting the MCS level based on the terminal with the worst channel state is as follows. As the channel state of the terminal with the worst channel state is larger than the average channel state, It is inefficient.

This is because as the lower MCS level is set, the base station must allocate more frequency bands in order to satisfy the target rate. However, other terminals with good channel status can receive data at a higher MCS level, This is because many frequency bands must be allocated until data is received at the MCS level.

In the present invention, as described above, as the gap between the channel states of the terminal having the worst channel state compared to the average channel state is increased (the number of terminals is increased), the frequency efficiency is lowered. And the frequency efficiency is reduced in proportion to the number.

A base station apparatus 100 according to the present invention will now be described.

The base station apparatus 100 groups all of the terminals into the first group and the remaining terminals into the second group in all the terminals (1,2,3 ... 10) to which the multicast service is provided.

For example, as shown in FIG. 1, the base station apparatus 100 groups terminals 1, 2, 3, and 4 into a first group G1, 10 into the second group G2.

Then, the base station apparatus 100 allocates an additional frequency band to the first group G1.

That is, the base station apparatus 100 further allocates an additional frequency band to the first group G1 in addition to the basic frequency band for providing the multicast service to all the terminals 1, 2, 3 ... 10 .

Then, the base station apparatus 100 sets the data processing method, i.e., MCS, differently in each of the basic frequency band and the additional frequency band.

Then, the base station apparatus 100 provides a multicast service to all the terminals (1, 2, 3 ... 10) based on the MCS level set in the basic frequency band through the basic frequency band, 3 and 4 in the first group G1 based on the MCS level set in the additional frequency band.

That is, in the present invention, based on one MCS level set in focus on a terminal (for example, terminal 1) having the worst channel state among all terminals 1, 2, 3 ... 10 through the basic frequency band Unlike the existing SC-PTM that provides a multicast service to all terminals (1, 2, 3 ... 10), a group-based SC-PTM is proposed.

Hereinafter, the base station apparatus of the present invention, which realizes the group-based SC-PTM proposed in the present invention, will be described in more detail with reference to FIG.

2, a base station apparatus 100 according to the present invention includes a grouping unit 110 for grouping a plurality of terminals into a first group and a remaining group to a second group in all terminals to which a multicast service is provided, A frequency band role allocating unit 120 for allocating an additional frequency band to the first group, a data processing method setting unit 120 for setting a data processing mode in each of the basic frequency band and the additional frequency band for the multicast service differently, And providing the multicast service to all the MSs based on a data processing scheme set in the basic frequency band through the basic frequency band, And a service providing unit 140 for providing the multicast service to the terminal in the first group based on the set data processing method .

As described above, the base station apparatus 100 according to the present invention includes a Single-Cell Point-To-Point (SC-PTM) 100 capable of dynamically setting / adjusting a data processing scheme, i.e., a Modulation and Coding Scheme (MCS) It is desirable to provide a multicast service on the basis of a multi-point.

The grouping unit 110 groups all of the terminals into the first group and the remaining terminals into the second group in all the terminals to which the multicast service is provided.

Hereinafter, with reference to FIG. 1, it will be assumed that a plurality of terminals (1, 2, 3,... 10) are the objects of provision of the multicast service provided by the base station 100.

On the premise of this assumption, the grouping unit 110 divides the first group and the second group by grouping the terminals in all the terminals (1, 2, 3 ... 10).

The grouping process of the grouping unit 110 will be described in more detail as follows.

The grouping unit 110 groups some terminals whose channel quality information is equal to or less than a predetermined threshold value based on the channel quality information of the basic frequency band received from all terminals 1, 2, 3, ..., Group into groups.

Here, the basic frequency band refers to a frequency band used for providing a multicast service to all terminals (1, 2, 3 ... 10) as a default resource for a multicast service.

The grouping unit 110 receives channel quality (e.g., SNR) measurement results (hereinafter, referred to as channel quality information) measured in each base station from each of all terminals 1, 2, 3, (E.g., SNR) of the channel quality information is equal to or less than a threshold value, based on the channel quality information of each of all the received terminals 1, 2, 3, . Then, the grouping unit 110 groups the remaining terminals, which are not grouped into the first group among all terminals 1, 2, 3 ... 10, into the second group.

That is, among all the terminals (1, 2, 3,...) 10 to which the multicast service is provided, terminals whose channel quality (SNR) And terminals having a channel quality (e.g., SNR) exceeding a threshold value in a basic frequency band, i.e., terminals having a good channel state, are grouped into a second group.

Hereinafter, for convenience of description, as shown in Fig. 1, terminals 1, 2, 3, and 4 among all the terminals 1, 2, 3 ... 10 are grouped into a first group G1, , 6, 7, 8, 9, and 10 are grouped into the second group G2.

The frequency band role assignment unit 120 allocates an additional frequency band to the first group G1.

Here, the additional frequency band is an additional resource for the multicast service, and a rate or throughput that the terminal in the first group G1 having a bad channel state in the basic frequency band can not obtain in the basic frequency band is compensated Means the frequency band used for

In other words, in addition to the basic frequency band for providing a multicast service to all the terminals (1,2,3 ... 10), the frequency band role part 120 further adds an additional frequency band to the first group G1 Quot;

The data processing mode setting unit 130 sets the data processing method, i.e., MCS, differently in each of the basic frequency band and the additional frequency band for the multicast service.

The data processing method, or MCS, can be divided into several levels based on 16QAM (for example, 10 to 16), various levels based on QPSK (for example, 0 to 9) ~ 28).

Hereinafter, for convenience of description, various levels (for example, 10 to 16) based on 16QAM will be described, and the data processing method and the MCS will be used interchangeably according to the same meaning.

A process of setting a data processing method (MCS) in each of the basic frequency band and the additional frequency band will be described in detail as follows.

First, the process of setting the data processing method (MCS) in the basic frequency band will be described.

The data processing mode setting unit 130 sets the data processing mode setting unit 130 to set the data processing mode to be the same as the channel frequency of the basic frequency band received from the terminals 5,6,7,8,9,10 in the second group G2 having good channel quality (e.g., SNR) Based on the quality information, a terminal having the smallest channel quality information value (e.g., SNR) among terminals 5, 6, 7, 8, 9 and 10 in the second group G2 is referred to as a data processing method That is, the MCS level is set.

As described above, the base station apparatus 100 obtains channel quality (e.g., SNR) measurement results (hereinafter, referred to as channel quality Information).

Based on the channel quality information of the received basic frequency band thus received from the terminals 5, 6, 7, 8, 9 and 10 in the second group G2, the data processing mode setting unit 130 sets The MCS level is set in the base frequency band based on the terminal having the smallest channel quality information value (e.g., SNR) among terminals 5, 6, 7, 8, 9, and 10 in the group G2.

For example, it can be assumed that the value (e.g., SNR) of the channel quality information received at the terminal 5 is the smallest.

In this case, the data processing mode setting unit 130 sets the data processing mode setting unit 130 to set the terminal 5 having the smallest channel quality information value (e.g., SNR) among the terminals 5, 6, 7, 8, 9 and 10 in the second group G2 , The MCS level is set in the basic frequency band.

That is, in the present invention, the MCS level in the basic frequency band to be used in all the terminals (1, 2, 3 ... 10) to which the multicast service is provided is the first group 6, 7, 8, 9, and 10 in the second group G2 having relatively good channel status are excluded and only the terminals 5, 6, 7, 8, 9 in the second group G2 , The MCS level is set with a focus on a terminal having the worst 10-channel state (e.g., terminal 5).

On the other hand, the data processing mode setting unit 130 sets the data processing method, that is, the MCS level, in the additional frequency band separately from setting the MCS level in the basic frequency band as described above.

The data processing mode setting unit 130 sets the data processing mode of the additional frequency band received from the terminals 1, 2, 3, and 4 in the first group G1 having a poor channel quality (e.g., SNR) That is, the MCS level in the additional frequency band based on the terminal having the smallest channel quality information value (e.g., SNR) among the terminals 1, 2, 3 and 4 in the first group G1 Setting.

After allocating an additional frequency band to the first group G1, the base station apparatus 100 acquires the channel quality measured by each terminal in the additional frequency band from each of the terminals 1, 2, 3, and 4 in the first group G1, (E.g., SNR) measurement result (hereinafter referred to as channel quality information).

Therefore, the data processing mode setting unit 130 sets the data processing mode setting unit 130 in the first group G1 based on the channel quality information of the received additional frequency band received from the terminals 1, 2, 3, and 4 in the first group G1, The MCS level is set in the additional frequency band based on the terminal having the smallest value (e.g., SNR) of the channel quality information of the terminals 1, 2, 3,

For example, it can be assumed that the value (e.g., SNR) of the channel quality information received at the terminal 1 is the smallest.

In this case, the data processing mode setting unit 130 sets the data processing mode setting unit 130 to use the additional frequency (for example, 1 MHz) based on the terminal 1 having the smallest channel quality information value (e.g., SNR) among the terminals 1, Set the MCS level in the band.

That is, in the present invention, the MCS level in the additional frequency band to be used in the terminals 1, 2, 3, and 4 in the first group G1 in the base frequency band, The MCS level is set with a focus on the terminal having the worst channel state of 1, 2, 3, or 4 (for example, terminal 1).

Here, the MCS level set in the basic frequency band considering the second group G2 having a relatively good channel state is higher than the MCS level set in the additional frequency band considering the relatively poor first group G1 will be.

Hereinafter, for convenience of explanation, it is assumed that the MCS level set in the basic frequency band is MCS 15, and the MCS level set in the additional frequency band is MCS 11.

In this manner, the data processing mode setting unit 130 can set the MCSs differently in the basic frequency band and the additional frequency band for the multicast service (MCS 15, MCS 11).

The service providing unit 140 provides the multicast service to all the terminals (1, 2, 3, ...) 10 based on the data processing method set in the basic frequency band, that is, the MCS 15, And provides the multicast service to the terminals 1, 2, 3, and 4 in the first group G1 based on the data processing method set in the additional frequency band, i.e., MCS 11, through the additional frequency band.

That is, the service providing unit 140 modulates and codes the data of the multicast service on the basis of the MCS 15, and transmits the data to all the terminals 1, 2, 3 ... 10 through the basic frequency band, Lt; / RTI >

In addition, the service providing unit 140 modulates and codes data of the multicast service based on the MCS 11 and transmits the data to the terminals 1, 2, 3 and 4 in the first group G1 through the additional frequency band, And provides a multicast service.

In this case, in the case of terminals 5, 6, 7, 8, 9, and 10 in the second group G2 having a relatively good channel state, data of the multicast service received through the base frequency band is demodulated and demodulated based on MCS 15 By decoding, a multicast service can be used.

In addition, in the case of the first, second, third, and fourth groups G1 in the relatively inferior channel state, the data of the multicast service received through the base frequency band is received through the additional frequency band based on the MCS 15 Data of the multicast service is demodulated and decoded based on the MCS 11, so that the multicast service can be used by combining the two frequency bands.

In this case, the UEs 1, 2, 3, and 4 in the first group G1, which have poor channel conditions, can reduce the rate or throughput that is not obtained due to the high MCS 15 in the basic frequency band to a low MCS 11 will be compensated.

As shown in FIG. 4 (a), if all the UEs (1, 2, 3,... 10) to which the multicast service is provided in the base frequency band have the worst channel conditions : MCS 11 (MCS 11) would have been set to focus on terminal 1).

Therefore, in the past, all of the terminals 1, 2, 3, ..., 10 would have received data of the multicast service in an MCS (e.g., MCS 11) set lower than necessary in the basic frequency band

Accordingly, since a low MCS level MCS (for example, MCS 11) is set as shown in FIG. 4 (a), the target rate To satisfy the requirement, the base station had to allocate more frequency bands until it received data at a lower MCS level than necessary, although terminals with good channel conditions could receive data at a higher MCS level.

However, according to the present invention (group-based SC-PTM), as shown in FIG. 4B, the UEs 5, 6, 7, 8, 9 and 10 in the second group (G2) (E.g., MCS 11) is set considering only the UEs 1, 2, 3, and 4 in the first group G1 where channel conditions are relatively poor in the additional frequency band, Is set.

4B, in the present invention, in order to satisfy the target rate at all terminals (1, 2, 3 ... 10) as compared with the existing SC-PTM, It is possible to improve the problem phenomenon of the existing SC-PTM in which the frequency efficiency is reduced in proportion to the number of terminals that are the targets of the multicast service.

On the other hand, since the radio environment between the base station and the mobile station varies from time to time, a process of dynamically adjusting the data processing method, that is, the MCS level is required.

To this end, the base station apparatus 100 of the present invention can operate a feedback channel for receiving feedback information related to the fundamental frequency band, and a feedback channel for receiving feedback information related to the additional frequency band, respectively. That is, two feedback channels are operated.

In the present invention, in the case of the terminals 5, 6, 7, 8, 9 and 10 in the second group G2, feedback information related to the fundamental frequency band is transmitted to the base station apparatus 100, And transmits the feedback information related to the additional frequency band to the base station apparatus 100 in the case of the terminals 1, 2, 3,

At this time, the feedback information means information including ACK notifying that it is normally received at the time of reception and NACK informing that it is not received at the time of non-reception in units of data packets received through the frequency band.

Accordingly, the data processing mode setting unit 130 dynamically adjusts the MCS level (for example, MCS 15) previously set in the basic frequency band and the MCS level (for example, MCS 11) set in the additional frequency band.

Specifically, the data processing mode setting unit 130 sets the data processing mode, i.e., the MCS level, in the additional frequency band based on the additional frequency band related feedback information received from the terminals 1, 2, 3, .

That is, if the number of NACKs is more than a certain number (for example, one or a plurality of M) based on the feedback information received through the feedback channel of the additional frequency band, (Eg, MCS 11 -> MCS 12) set in the additional frequency band if the NACK is not acknowledged for a predetermined time (TTIs) Can be adjusted.

On the other hand, the data processing mode setting unit 130 sets the data processing mode in the basic frequency band based on the basic frequency band related feedback information received from the terminals 5, 6, 7, 8, 9 and 10 in the second group G2 That is, the MCS level is adjusted.

That is, if the number of NACKs is more than a certain number (for example, one, a plurality of M) based on the feedback information received through the feedback channel of the fundamental frequency band, (Eg, MCS 15 -> MCS 16) set in the basic frequency band if the NACK is not confirmed for a predetermined time (TTIs) Can be adjusted.

On the other hand, since the mobile station can be in good or bad channel condition due to movement and vice versa, it is necessary to support the movement between the first group and the second group.

To do this, the grouping unit 110 may move a specific terminal in the first group G1 to the second group G2 and move a specific terminal in the second group G2 to the first group G1 have.

At this time, the specific terminal in the first group G1 is a terminal that satisfies a target rate as a result of decoding data of the multicast service using only the basic frequency band without using an additional frequency band.

More specifically, in the present invention, in the case of the terminals 1, 2, 3, and 4 in the first group G2, the multicast service is used by combining the two frequency bands (basic and additional) It is possible to periodically perform an operation of demodulating and decoding data of the multicast service using only the basic frequency band (MCS 15) without using the additional frequency band.

Accordingly, among the terminals 1, 2, 3, and 4 in the first group G2, an operation of demodulating and decoding the data of the multicast service using only the basic frequency band (MCS 15) without periodically using the additional frequency band is performed As a result, if there is a terminal satisfying a target rate, the base station apparatus 100 of the present invention recognizes this terminal (hereinafter referred to as a specific terminal in the first group G1).

Accordingly, the grouping unit 110 can move the specific terminal (for example, terminal 4 in FIG. 1) in the first group G1 recognized as described above to the second group G2.

On the other hand, the specific terminal in the second group G2 is a terminal whose channel quality value measured in the basic frequency band falls below a preset threshold value.

More specifically, in the present invention, in the case of the terminals 5, 6, 7, 8, 9 and 10 in the second group G2, it is possible to periodically measure the channel quality (e.g., SNR) thereof.

As a result of measuring the channel quality (e.g., SNR) of the UE 5, 6, 7, 8, 9, and 10 in the second group G2 periodically, if the channel quality value falls below a preset threshold value If there is a terminal, the base station apparatus 100 of the present invention recognizes this terminal (hereinafter referred to as a specific terminal in the second group G2).

Accordingly, the grouping unit 110 can move the specific terminal (e.g., terminal 6 of FIG. 1) in the second group G1 recognized as described above to the first group G1.

The threshold value used to move a specific terminal in the second group G2 to the first group G1 may be determined by dividing the entire terminal 1, 2, 3, ... 10 into a first group G1 and a second group G2, May be equal to the threshold value used when dividing into the second group G2.

As described above, the base station apparatus 100 according to the present invention proposes a group-based SC-PTM to provide a multicast service in which the frequency efficiency is reduced in proportion to the number of terminals, Can be efficiently improved.

Hereinafter, an operation method of the base station apparatus according to the present invention will be described with reference to FIG. For convenience of explanation, the reference numerals of Figs. 1 and 2 will be described.

In the operation method of the base station apparatus 100 according to the present invention, all the terminals to which a multicast service is provided are grouped into a first group and a remaining group to a second group (S100).

Hereinafter, with reference to FIG. 1, it will be assumed that a plurality of terminals (1, 2, 3,... 10) are the objects of provision of the multicast service provided by the base station 100.

Based on this assumption, the operating method of the base station apparatus 100 according to the present invention is based on the channel quality information of the base frequency band received from all of the terminals 1, 2, 3 ... 10, To a first group in which some UEs whose values are equal to or less than a preset threshold value.

That is, the method of operating the base station apparatus 100 according to the present invention is a method of measuring channel quality (e.g., SNR) measurement results measured in each base station from each of all terminals 1, 2, 3, (E.g., SNR) of the channel quality information based on the channel quality information of each of all the received terminals 1, 2, 3, ..., Or less are grouped into the first group. The method of operation of the base station apparatus 100 according to the present invention groups the remaining terminals not grouped into the first group among all the terminals 1, 2, 3 ... 10 into a second group.

Hereinafter, for convenience of description, as shown in Fig. 1, terminals 1, 2, 3, and 4 among all the terminals 1, 2, 3 ... 10 are grouped into a first group G1, , 6, 7, 8, 9, and 10 are grouped into the second group G2.

Thereafter, an operation method of the base station apparatus 100 according to the present invention allocates an additional frequency band to the first group G1 (S110).

In other words, the method of operating the base station 100 according to the present invention is characterized in that, in addition to the basic frequency band for providing a multicast service to all terminals 1, 2, 3 ... 10, To allocate more frequency bands to the base station.

The method of operation of the base station apparatus 100 according to the present invention sets the data processing method, that is, the MCS, in the basic frequency band and the additional frequency band for the multicast service differently (S120 and S130).

Hereinafter, for convenience of description, various levels (for example, 10 to 16) based on 16QAM will be described, and the data processing method and the MCS will be used interchangeably according to the same meaning.

A process of setting a data processing method (MCS) in each of the basic frequency band and the additional frequency band will be described in detail as follows.

First, the process of setting the data processing method (MCS) in the basic frequency band will be described.

The operation method of the base station apparatus 100 according to the present invention is a method of operating the base station apparatus 100 according to the first embodiment of the present invention. Based on the channel quality information of the frequency band, a terminal having the smallest value (e.g., SNR) of channel quality information among the terminals 5, 6, 7, 8, 9 and 10 in the second group G2, I.e., an MCS level, at step S120.

As described above, the base station apparatus 100 obtains channel quality (e.g., SNR) measurement results (hereinafter, referred to as channel quality Information).

The method of operation of the base station apparatus 100 according to the present invention is based on the channel quality information of the received basic frequency band received from the terminals 5, 6, 7, 8, 9 and 10 in the second group G2 And sets the MCS level in the basic frequency band based on the terminal having the smallest channel quality information value (e.g., SNR) among the terminals 5, 6, 7, 8, 9, and 10 in the second group G2.

For example, it can be assumed that the value (e.g., SNR) of the channel quality information received at the terminal 5 is the smallest.

In this case, the operation method of the base station apparatus 100 according to the present invention is a method in which the value (e.g., SNR) of channel quality information among the terminals 5, 6, 7, 8, 9 and 10 in the second group G2 is the smallest The MCS level is set in the basic frequency band on the basis of the terminal 5.

Meanwhile, the method of operating the base station apparatus 100 according to the present invention sets the data processing method, i.e., the MCS level, in the additional frequency band separately from setting the MCS level in the basic frequency band as described above (S120) S130).

The method of operation of the base station apparatus 100 according to the present invention is characterized in that the base station apparatus 100 receives the additional Based on the channel quality information of the frequency band, a terminal having the smallest channel quality information value (e.g., SNR) among the terminals 1, 2, 3 and 4 in the first group G1 as a reference, That is, the MCS level is set.

After allocating an additional frequency band to the first group G1, the base station apparatus 100 acquires the channel quality measured by each terminal in the additional frequency band from each of the terminals 1, 2, 3, and 4 in the first group G1, (E.g., SNR) measurement result (hereinafter referred to as channel quality information).

The method of operation of the base station apparatus 100 according to the present invention is based on the channel quality information of the received additional frequency band received from the terminals 1, 2, 3, and 4 in the first group G1, The MCS level is set in the additional frequency band based on the terminal having the smallest channel quality information value (e.g., SNR) among the terminals 1, 2, 3, and 4 in the group G1.

For example, it can be assumed that the value (e.g., SNR) of the channel quality information received at the terminal 1 is the smallest.

In this case, the operation method of the base station apparatus 100 according to the present invention is a method in which the terminal 1 having the lowest channel quality information value (e.g., SNR) among the terminals 1, 2, 3, , The MCS level is set in the additional frequency band.

Here, the MCS level set in the basic frequency band considering the second group G2 having a relatively good channel state is higher than the MCS level set in the additional frequency band considering the relatively poor first group G1 will be.

Hereinafter, for convenience of explanation, it is assumed that the MCS level set in the basic frequency band is MCS 15, and the MCS level set in the additional frequency band is MCS 11.

The operation method of the base station apparatus 100 according to the present invention is a method in which all terminals 1, 2, 3, ..., 10 are connected to a multi- And provides the multicast service to the terminals 1, 2, 3, and 4 in the first group G1 based on the data processing method set in the additional frequency band, that is, the MCS 11 through the additional frequency band ( S140).

That is, in the method of operating the base station apparatus 100 according to the present invention, the data of the multicast service is modulated and coded on the basis of the MCS 15 and transmitted to all the terminals (1, 2, 3 ... 10) Thereby providing a multicast service.

In addition, the method of operating the base station 100 according to the present invention modulates and codes the data of the multicast service based on the MCS 11, and transmits the modulated data to the terminals 1, 2, 3 in the first group G1 , 4 to provide a multicast service.

In this case, in the case of terminals 5, 6, 7, 8, 9, and 10 in the second group G2 having a relatively good channel state, data of the multicast service received through the base frequency band is demodulated and demodulated based on MCS 15 By decoding, the multicast service can be used (S150).

In addition, in the case of the first, second, third, and fourth groups G1 in the relatively inferior channel state, the data of the multicast service received through the base frequency band is received through the additional frequency band based on the MCS 15 The data of the multicast service is demodulated and decoded based on the MCS 11 so that the multicast service can be used by combining the two frequency bands (S150).

In this case, the UEs 1, 2, 3, and 4 in the first group G1, which have poor channel conditions, can reduce the rate or throughput that is not obtained due to the high MCS 15 in the basic frequency band to a low MCS 11 will be compensated.

Meanwhile, since the wireless environment changes occasionally between the base station and the terminal, a process of dynamically adjusting the data processing method, that is, the MCS level is required (S160, S165).

To this end, the method of operation of the base station apparatus 100 according to the present invention can operate a feedback channel for receiving feedback information related to a fundamental frequency band and a feedback channel for receiving feedback information related to an additional frequency band, respectively have. That is, two feedback channels are operated (S160).

In the present invention, in the case of the terminals 5, 6, 7, 8, 9 and 10 in the second group G2, feedback information related to the fundamental frequency band is transmitted to the base station apparatus 100, And transmits the feedback information related to the additional frequency band to the base station apparatus 100 in the case of the terminals 1, 2, 3,

Therefore, the method of operation of the base station apparatus 100 according to the present invention is based on two feedback channels, in which the MCS level (for example, MCS 15) set in the basic frequency band and the MCS level set in the additional frequency band : MCS 11) are respectively dynamically adjusted (S165).

More specifically, the method of operation of the base station apparatus 100 according to the present invention is a method for processing data in an additional frequency band based on additional frequency band related feedback information received from the terminals 1, 2, 3, 4 in the first group G1 I.e., the MCS level.

That is, the method of operating the base station apparatus 100 according to the present invention is a method in which when a number of NACKs is more than a certain number (for example, one or a plurality of M) based on feedback information received through a feedback channel of an additional frequency band If the MCS level (eg MCS 11 -> MCS 10) set in the additional frequency band has been lowered and the NACK has not been checked for a predetermined time (TTIs), the MCS level set in the additional frequency band (eg MCS 11 - > MCS 12).

The method of operation of the base station apparatus 100 according to the present invention may include the steps of receiving a baseband frequency band based on fundamental frequency band related feedback information received from the terminals 5, 6, 7, 8, 9, 10 in the second group G2, That is, the MCS level.

That is, the method of operation of the base station apparatus 100 according to the present invention is a method in which if a number of NACKs is more than a certain number (for example, one or a plurality of M) based on feedback information received through a feedback channel of a fundamental frequency band If the MCS level (for example, MCS 15 -> MCS 14) set in the basic frequency band is lowered and adjusted and the NACK is not checked for a predetermined time (TTIs) > MCS 16) can be adjusted.

Meanwhile, since the mobile station may be in a good channel condition due to movement, and the opposite case may be possible, a process of supporting movement between the first group and the second group is required (S170).

To this end, the method of operating the base station apparatus 100 according to the present invention is characterized in that the specific terminals in the first group G1 are moved to the second group G2, the specific terminals in the second group G2 are moved to the first group G2, (Step S170).

More specifically, in the present invention, in the case of the terminals 1, 2, 3, and 4 in the first group G2, the multicast service is used by combining the two frequency bands (basic and additional) It is possible to periodically perform an operation of demodulating and decoding data of the multicast service using only the basic frequency band (MCS 15) without using the additional frequency band.

Accordingly, among the terminals 1, 2, 3, and 4 in the first group G2, an operation of demodulating and decoding the data of the multicast service using only the basic frequency band (MCS 15) without periodically using the additional frequency band is performed As a result, if there is a terminal satisfying a target rate, the base station apparatus 100 of the present invention recognizes this terminal (hereinafter referred to as a specific terminal in the first group G1).

The operation method of the base station apparatus 100 according to the present invention can move the specific terminal (for example, the terminal 4 in FIG. 1) in the first group G1 recognized as described above to the second group G2 have.

Meanwhile, in the present invention, in the case of the terminals 5, 6, 7, 8, 9 and 10 in the second group G2, the channel quality (e.g., SNR) of its own can be periodically measured.

As a result of measuring the channel quality (e.g., SNR) of the UE 5, 6, 7, 8, 9, and 10 in the second group G2 periodically, if the channel quality value falls below a preset threshold value If there is a terminal, the base station apparatus 100 of the present invention recognizes this terminal (hereinafter referred to as a specific terminal in the second group G2).

The operation method of the base station apparatus 100 according to the present invention can move the specific terminal (for example, terminal 6 in FIG. 1) in the second group G1 recognized as described above to the first group G1 have.

At this time, the threshold value used to move the specific terminal in the second group G2 to the first group G1 is the same as the threshold used in the first group G1 G1) and the second group (G2).

The method of operation of the base station apparatus 100 according to the present invention will provide a multicast service while repeating the above and following steps S140 unless the multicast service is terminated (S180 No).

INDUSTRIAL APPLICABILITY As described above, the method of operating the base station apparatus according to the present invention can efficiently improve the frequency efficiency in proportion to the number of terminals that are the target of the multicast service in providing the multicast service.

The method of operating the base station according to an embodiment of the present invention may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and configured for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

According to the operation method of the base station apparatus and the base station apparatus according to the present invention, in efficiently providing the multicast service, the frequency efficiency is reduced in proportion to the number of terminals that are the targets of the multicast service, It is an invention that is industrially applicable because it is not only the use of related technology but also the possibility of market or operation of the applicable device as well as the possibility of being practically and practically obvious as it goes beyond the limit.

100: base station device
110: grouping unit 120: frequency band role request
130: data processing method setting unit 140:

Claims (10)

A grouping unit for grouping a plurality of terminals into a first group and a remaining group to a second group in all the terminals to which the multicast service is provided;
A frequency band role part allocating an additional frequency band to the first group;
A data processing scheme setting unit for setting data processing schemes differently in each of the fundamental frequency band for the multicast service and the additional frequency band; And
Providing the multicast service to all the terminals based on a data processing method set in the basic frequency band through the basic frequency band and providing a data processing method set in the additional frequency band through the additional frequency band And a service providing unit for providing the multicast service to the terminal in the first group based on the multicast service. The method according to claim 1,
The grouping unit,
And grouping, into the first group, some UEs whose channel quality information values are equal to or less than a preset threshold value, based on the channel quality information of the basic frequency band received from all the UEs. The method according to claim 1,
Wherein the data processing method setting unit comprises:
A data processing method in the additional frequency band is set based on the channel quality information of the additional frequency band received from the terminal in the first group on the basis of the terminal having the smallest channel quality information value among the terminals in the first group The base station apparatus comprising: The method according to claim 1,
Wherein the data processing method setting unit comprises:
A data processing method in the basic frequency band is set based on the channel quality information of the basic frequency band received from the terminal in the second group on the basis of the terminal having the smallest channel quality value among the terminals in the second group The base station apparatus comprising: The method according to claim 1,
The grouping unit moves a specific terminal in the first group to the second group,
Wherein the specific terminal in the first group is a terminal that satisfies a target rate as a result of decoding data of the multicast service using only the basic frequency band without using the additional frequency band. The method according to claim 1,
The grouping unit moves a specific terminal in the second group to the first group,
Wherein the specific terminal in the second group is a terminal whose channel quality value measured in the basic frequency band falls below a preset threshold value. A grouping step of grouping some terminals into a first group and the remaining terminals into a second group in all terminals to which a multicast service is provided;
A frequency band allocation step of allocating an additional frequency band to the first group;
A data processing method setting step of setting a data processing method in each of the basic frequency band and the additional frequency band for the multicast service differently; And
Providing the multicast service to all the terminals based on a data processing method set in the basic frequency band through the basic frequency band and providing a data processing method set in the additional frequency band through the additional frequency band And providing the multicast service to the terminals in the first group based on the multicast service. 8. The method of claim 7,
Wherein the grouping comprises:
And grouping, into the first group, some UEs whose channel quality information is less than or equal to a preset threshold value, based on the channel quality information of the basic frequency band received from the entire UE. 8. The method of claim 7,
The data processing method setting step includes:
A data processing method in the basic frequency band is set based on the channel quality information of the basic frequency band received from the terminal in the second group on the basis of the terminal having the smallest channel quality value among the terminals in the second group and,
A data processing method in the additional frequency band is set based on the channel quality information of the additional frequency band received from the terminal in the first group on the basis of the terminal having the smallest channel quality information value among the terminals in the first group The base station apparatus comprising: 8. The method of claim 7,
Based on feedback information related to the additional frequency band received from the terminal in the first group, and controls the data processing method in the additional frequency band based on the basic frequency band related feedback information received from the terminal in the second group Further comprising: adjusting a data processing scheme in the base frequency band.

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