KR101915108B1 - Base station and control method thereof - Google Patents

Abstract

The present invention relates to a base station apparatus and a base station apparatus capable of improving communication quality of both a CA terminal and a CA-not-supported terminal by realizing load balancing (SCell) of a CA terminal in consideration of an overall load environment of a base station We propose an operation method.

Description

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

The present invention relates to a method of operating a base station apparatus and a base station apparatus, and more particularly, to a method of operating a base station apparatus and a base station apparatus by realizing load balancing of an auxiliary cell (SCell) And more particularly, to a base station apparatus and a base station apparatus that can improve the communication quality of all of the terminals.

In the existing LTE system, it is possible to support high-speed communication service by using a bandwidth of up to 20 MHz. However, as the type of communication service and the speed of transmission demand have become diverse, there is an increasing demand for faster speed communication systems.

In recent years, an IMT-advanced communication system capable of supporting a wider band than the existing 20 MHz band has emerged. In an IMT-advanced communication system, in a case where a plurality of frequency bands coexist, (CA) technology to support a wider bandwidth.

CA technology can secure a broader frequency band through integration of multiple unit frequency bands (CCs), and since each frequency band (CC) is used as an LTE frequency band for LTE terminals, So that compatibility can be maintained.

A terminal supporting the CA function (hereinafter referred to as a CA terminal) firstly accesses a base station through a primary cell (PCell) of a base frequency band in which an initial connection among a plurality of frequency bands CC is designated, Accordingly, it is possible to simultaneously access the base station through a secondary cell (SCell) in the auxiliary frequency band, and to use communication services by integrating cells of various frequency bands, that is, PCell and SCell.

Of course, in the LTE system, not only the CA terminal but also the terminal before the CA technology emerges, that is, terminals that do not support the CA function (hereinafter, CA supported terminal) coexist.

In this case, when the CA terminal accesses the base station through the base frequency band (PCell), the base station notifies the CA terminal of which sub-frequency band cell should be used as the auxiliary cell (SCell) (Assigned) according to the reception environment.

Thereafter, when the auxiliary cell (SCell) of the CA terminal is changed, when a new auxiliary cell (SCell) is designated as the basic cell (PCell) is changed or when the signal reception environment of the current auxiliary cell (SCell) And the auxiliary cell (SCell) is designated.

However, since the above-described conventional SCell changing method considers only the position of the CA terminal and does not consider the entire load environment of the base station, it is connected to the corresponding cell as viewed from the side of the auxiliary cell SCell It may adversely affect the communication quality of all terminals.

Accordingly, the present invention proposes a method of realizing SCell load balancing considering the overall load environment of the base station, that is, the overall load environment reflecting both the CA terminal and the CA unsupported terminal.

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 an apparatus and method for realizing load balancing of an auxiliary cell (SCell) of a CA terminal in consideration of an overall load environment of a base station, And a method of operating a base station apparatus and a base station apparatus capable of improving communication quality of all CA unsupported terminals.

According to a first aspect of the present invention, there is provided a base station apparatus including an overload checking unit for checking a specific cell in an overloaded state among a plurality of cells based on a load amount for each of a plurality of cells; An information obtaining unit for obtaining measurement information on a candidate cell that can be changed among at least one candidate terminal using the specific cell as a secondary cell among the terminals connected to the specific cell; A terminal selecting unit for selecting a changing terminal among the candidate terminals based on the plurality of cell load amounts and the obtained measurement information; And a control unit for handing over the auxiliary cell of the changing terminal from the specific cell to a candidate cell of the changing terminal.

Preferably, the information obtaining unit provides a policy to the at least one candidate terminal to report to the base station device measurement information on a neighbor cell whose signal strength is greater than or equal to a predetermined threshold value, among neighboring cells other than the connected cell, From the at least one candidate terminal, measurement information for the neighboring cell reported according to the policy, as measurement information for the changeable candidate cell.

Preferably, the terminal selection unit selects a candidate cell having the smallest load among the candidate cells according to the obtained measurement information, based on the load amount for each of the plurality of cells and the obtained measurement information, A candidate terminal reporting measurement information on the selected candidate cell among the terminals can be selected as the changing terminal.

Preferably, the candidate cell of the changing terminal may be a candidate cell having the smallest load among the candidate cells according to the obtained measurement information.

According to a second aspect of the present invention, there is provided an operation method of a base station apparatus, comprising: an overload checking step of checking a specific cell in an overloaded state among a plurality of cells based on a load amount for each of a plurality of cells; An information obtaining step of obtaining measurement information on a candidate cell which can be changed among at least one candidate terminal using the specific cell as a secondary cell among the terminals connected to the specific cell; A terminal selecting step of selecting a changing terminal among the candidate terminals based on the plurality of cell load amounts and the obtained measurement information; And a connection control step of handing over the auxiliary cell of the changing terminal from the specific cell to a candidate cell of the changing terminal.

Preferably, the method further comprises the step of providing a policy to the at least one candidate terminal to report to the base station measurement information for neighboring cells whose signal strength among adjacent cells other than the connected cell is greater than or equal to a predetermined threshold value; The information obtaining step may obtain measurement information on the neighboring cell reported from the at least one candidate terminal according to the policy as measurement information for the changeable candidate cell.

Preferably, the terminal selecting step selects a candidate cell having the smallest load among the candidate cells according to the obtained measurement information, based on the load amount for each of the plurality of cells and the obtained measurement information, A candidate terminal reporting measurement information on the selected candidate cell among the candidate terminals may be selected as the changing terminal.

Preferably, the candidate cell of the changing terminal may be a candidate cell having the smallest load among the candidate cells according to the obtained measurement information.

According to the operation method of the base station apparatus and the base station apparatus of the present invention, the load balancing of the auxiliary cell (SCell) of the CA terminal in consideration of the overall load environment of the base station is realized, And the like.

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.

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.

As shown in FIG. 1, in the communication system including the base station apparatus 100 of the present invention, a plurality of frequency bands coexist in the same area.

For example, referring to FIG. 1, the base station apparatus 100 includes a plurality of frequency bands, for example, a first frequency band B1, a second frequency band B2, and a third frequency band B3 In the cell view, the base station apparatus 100 may include a plurality of cells, for example, cells B1_a, B1_b ... B1_f according to the first frequency band, cells B2_a ... B2_c ) And cells B3_a ... B3_c according to the third frequency band.

The present invention is related to a Carrier Aggregation (CA) technique adopted in an IMT-advanced communication system that has been introduced to support a wider band than the existing 20 MHz band.

Here, the CA technology can secure a wider frequency band through the integration of multiple unit frequency bands (CCs), and since each unit frequency band (CC) is used as an LTE frequency band for LTE terminals, So that compatibility with the system can be maintained.

1, not only a terminal supporting a CA function (hereinafter referred to as CA terminal) but also a terminal not supporting a CA function (hereinafter referred to as a CA unsupported terminal) are connected to the cells formed in the base station apparatus 100 It coexists.

Accordingly, the base station apparatus 100 according to the present invention can be applied to any one of frequency bands (e.g., a first frequency band, a second frequency band, and a third frequency band) (CA terminal, CA-not-supported terminal) connected to the base station through the CA function, and in particular, for the terminal functioning as the CA function, the communication service utilizing the CA function, that is, integrating cells of two or more frequency bands, It will be a CA-supported base station that can provide.

When the terminal 1 is powered on, the terminal 1 is connected to the base station 100 through one of the frequency bands of the plurality of frequency bands.

At this time, since the terminal 1 is the CA terminal, the terminal 1 is connected to the base station apparatus 100 through the frequency band designated with a high priority in the priority information for each frequency band, that is, the frequency band designated for initial connection. And the cell of the fundamental frequency band used for connection with the base station apparatus 100 corresponds to a primary cell (PCell).

The terminal 1 is connected to the base station apparatus 100 through the base cell (PCell) in the basic frequency band and then transmitted to the base station apparatus 100 through a secondary cell (SCell) of at least one sub- (PC) and SCell of a plurality of frequency bands, thereby making it possible to use communication services.

At this time, when the terminal 1 accesses the base station apparatus 100 through the base cell (PCell), the base station apparatus 100 determines which sub frequency band of the terminal 1 should be used as the auxiliary cell (SCell) 100), and assigns (Add, assigns) it according to a signal receiving environment reported from the CA terminal or internally.

If the auxiliary cell (SCell) of the terminal 1 is changed according to the conventional method of changing the auxiliary cell (SCell), a new auxiliary cell (SCell) is designated Or a new auxiliary cell (SCell) is designated when the reception environment of the current auxiliary cell (SCell) signal deteriorates.

However, the above-described conventional SCELL changing method considers only the position of the terminal 1, that is, the CA terminal, and the entire load environment of the base station, that is, the consideration of the entire load environment in which both the CA terminal and the CA non- .

Accordingly, if the existing auxiliary cell (SCell) changing method described above is used, if the signal receiving environment is good in the terminal 1, the auxiliary cell (SCell) of the terminal 1 changes to the corresponding cell regardless of the current load amount of the corresponding cell And the change of the SCELL of the CA terminal will adversely affect the communication quality of all the terminals connected to the cell, particularly the CA terminal, when viewed from the side of the auxiliary cell SCell.

Accordingly, the present invention proposes a method of realizing SCell load balancing considering the overall load environment of the base station 100, that is, the entire load environment reflecting both the CA terminal and the CA-not-supported terminal .

To this end, the base station apparatus 100 according to the present invention identifies a specific cell in an overloaded state among a plurality of cells based on a load amount per a plurality of cells.

Then, the base station apparatus 100 receives, from at least one candidate terminal (CA terminal) using a specific cell among the terminals connected to the specific cell in the overload state as a secondary cell, And acquires measurement information about the cell.

Then, the base station apparatus 100 selects a changing terminal from among the candidate terminals based on the load amount per a plurality of cells and the obtained measurement information, and performs handover from the specified cell to the candidate cell of the changing terminal, .

Hereinafter, a configuration of a base station apparatus according to a preferred embodiment of the present invention will be described in detail with reference to FIG. For convenience of explanation, reference will be made to the above-mentioned reference numerals.

The base station apparatus 100 according to the present invention includes an overload checking unit 110 for identifying a specific cell in an overloaded state among the plurality of cells based on a load amount for each of a plurality of cells, An information obtaining unit (120) for obtaining measurement information on a candidate cell that can be changed from at least one candidate terminal using a specific cell as a secondary cell; And a controller (130) for selecting a changing terminal among the candidate terminals based on the obtained measurement information, and a controller (130) for handing over the auxiliary cell of the changing terminal from the specific cell to a candidate cell of the changing terminal 140).

Here, the base station apparatus 100 provides a plurality of frequency bands, for example, a first frequency band B1, a second frequency band B2 and a third frequency band B3 as shown in Fig. 1, A plurality of cells B1_a, B1_b ... B1_f according to the first frequency band, cells B2_a ... B2_c according to the second frequency band, cells B3_a ... B3_c according to the third frequency band, Can be formed.

As described above, the base station apparatus 100 is capable of providing a communication service utilizing the CA function, that is, a CA supporting base station (BS) capable of providing communication services by integrating cells of two or more frequency bands, would.

The overload checking unit 110 identifies a specific cell in an overload state among a plurality of cells based on a load amount per a plurality of cells.

1, a plurality of cells are divided into cells B1_a, B1_b ... B1_f in the first frequency band, cells B2_a ... B2_c in the second frequency band, and cells (B3_a ... B3_c).

In this case, the overload checking unit 110 determines the number of cells B1_a, B1_b, ..., B1_b, ..., B1_b, ..., B1_f, B2_a ... B2_c, B3_a ... B3_c) of the overloaded state.

More specifically, the overload checking unit 110 determines the load amount per a plurality of cells B1_a, B1_b, ... B1_f, B2_a ... B2_c, B3_a ... B3_c by a predetermined load amount checking period T1 Can be confirmed.

Hereinafter, a process of confirming the load amount for each of a plurality of cells B1_a, B1_b, B1_f, B2_a, B2_c, B3_a, ..., B3_c will be described.

For example, the overload checking unit 110 determines the number of terminals in the active state connected to the cell, for each of the plurality of cells B1_a, B1_b, ... B1_f, B2_a ... B2_c, B3_a ... B3_c, And a radio resource usage amount of the cell, and confirm the load amount of the corresponding cell as a result of the collection.

A cell B2_b of the second frequency band B2 as one of the plurality of cells B1_a, B1_b, B1_f, B2_a, B2_c, B3_a, ... B3_c will be described below.

The overload checking unit 110 collects the number of terminals in the active state connected to the cell B2_b at every load checking period T1.

At this time, an active terminal connected to the cell B2_b may include a CA unsupported terminal connected to the cell B2_b, and a CA terminal connected to the cell B2_b using the cell B2_b as a base cell (PCell) (Including CA function activation and deactivation), and CA terminal (CA function activation) connected by using cell B2_b as an auxiliary cell (SCell) may also be included.

Alternatively, the overload checking unit 110 collects the radio resource usage amount of the cell B2_b every load amount checking period T1.

At this time, the radio resource usage amount of the cell B2_b may include a radio resource usage amount used by the CA supported terminal connected to the cell B2_b, and may include the amount of radio resources used by the CA terminal MS connected with the cell B2_b as a basic cell (Including CA function activation and deactivation), and the amount of radio resources used by the CA terminal (CA function activation) connected by using the cell B2_b as an auxiliary cell (SCell) may also be included .

Thus, the overload checking unit 110 sets the number of terminals and the radio resource usage in the active state collected for the cell B2_b to the load amount of the cell B2_b at every load checking period T1 as described above .

The overload checking unit 110 checks the number of cells B1_a, B1_b ... B1_f, B2_a ... B2_c, B3_a ... B3_c ), Respectively.

Thereafter, the overload checking unit 110 determines whether or not the overload checking unit 110 is based on the load amount per a plurality of cells B1_a, B1_b, ... B1_f, B2_a ... B2_c, B3_a ... B3_c, B1_f, B2_a, B2_c, B3_a ... B3_c of the cells B1_a, B1_b, ..., B1_f, B2_a, ..., B3_c.

For example, the overload checking unit 110 determines the number of terminals in the active state, that is, the number of terminals in the active state, and the number of terminals in the radio resource (B3_a, B3_a, B3_a, If there is a cell (for example, B2_b) whose number of terminals in the active state is equal to or larger than a predetermined first overload threshold value or whose radio resource usage is equal to or greater than a predetermined second overload threshold value, the cell B2_b is overloaded It can be confirmed that it is a specific cell in the state.

Hereinafter, for convenience of description, it is noted that the cell B2_b among the plurality of cells B1_a, B1_b, B1_f, B2_a, B2_c, B3_a ... B3_c is identified as a specific cell in the overload state I will explain it.

When a specific cell is identified by the overload checking unit 110, the information obtaining unit 120 obtains information on a cell from at least one candidate terminal using a particular cell as a spare cell (SCell) B1_a, B1_b, B1_f, B2_a, B2_c, B3_a, and B3_c of the candidate cells.

More specifically, the information obtaining unit 120 selects at least one candidate terminal using the cell B2_b among the terminals connected to the specific cell, for example, the cell B2_b as the auxiliary cell SCell.

A terminal connected to the cell B2_b is connected to a CA terminal (connected to the cell B2_b), a CA terminal (including both the CA function activation and deactivation) connected by using the cell B2_b as a base cell PCell, And the CA terminal (CA function activation) connected using the second cell (B2_b) as the auxiliary cell (SCell).

The information acquiring unit 120 acquires the CA terminal (CA function activation) connected by using the cell B2_b as the auxiliary cell SCell among the terminals connected to the cell B2_b to the at least one candidate terminal Can be selected.

At this time, the information obtaining unit 120 may select all of the connected CA terminals (CA function activated) using the cell B2_b as the auxiliary cell SCell as the candidate terminal, or may select the cell B2_b as the auxiliary terminal (SCell), and may select randomly some of the connected CA terminals (CA function activation) and select them as candidate terminals.

Hereinafter, for convenience of explanation, the terminals 1, 2, 3, 4, and 5 will be described as at least one selected candidate terminal. In other words, it is assumed that the terminals 1, 2, 3, 4, and 5 are CA terminals (CA function activation) using the overloaded cell B2_b as the auxiliary cell SCell.

The information acquisition unit 120 acquires a plurality of cells B1_a, B1_b, ... B1_f, B2_a ... B2_c, B3_a ... B3_c Of the candidate cell.

More specifically, the information obtaining unit 120 determines at least one of the neighboring cells other than the connected cell to report the measurement information on the neighboring cell whose signal strength is equal to or greater than a preset threshold value to the base station apparatus 100 2, 3, 4, and 5, respectively.

The policy at this time is preferably the A4 event policy to report the A4 (A4) event.

In other words, the information obtaining unit 120 loads the A4 event policy including the preset threshold value (A4 threshold) and the A4 event in the rrcConnectionReconfiguration message to at least one candidate terminal, i.e., terminal 1, 2, .

Accordingly, each of the terminals 1, 2, 3, 4, and 5 that have received the A4 event policy transmits the signal strength of the neighboring cell in addition to the cell B2_b used as the connected cell, that is, the auxiliary cell SCell, (For example, PCI, RSRP, RSRQ, etc.) to the base station apparatus 100 when the adjacent cell having the measured signal strength is equal to or greater than the threshold value (A4 threshold) thereby performing an operation of reporting the result.

In this case, the adjacent cell that measures the signal strength (e.g., RSRP, RSRQ) according to the A4 event policy includes the cell in the same frequency band as the cell B2_b used as the connected cell, that is, the auxiliary cell SCell And a cell of a frequency band different from that of the cell B2_b.

As described above, each of the terminals 1, 2, 3, 4, and 5 provided with the A4 event policy reports the measurement information about the adjacent cell that can be assigned (assigned and assigned) to the base station apparatus 100 via the A4 event )can do.

Accordingly, the information obtaining unit 120 obtains the measurement information on the neighboring cells reported according to the A4 event policy from the candidate terminals, i.e., the terminals 1, 2, 3, 4, and 5, as the measurement information on the changeable candidate cell .

Measurement information on the cell B1_c is obtained from the terminals 1, 3 and 4 among the candidate terminals, i.e., the terminals 1, 2, 3, 4 and 5, and measurement information on the cell B3_b Is obtained.

The terminal selection unit 130 selects the change terminal from the candidate terminal based on the load amount and the obtained measurement information for each of the plurality of cells B1_a, B1_b ... B1_f, B2_a ... B2_c, B3_a ... B3_c do.

As described in the foregoing, the base station apparatus 100 confirms the loading amount for each of the plurality of cells B1_a, B1_b, ... B1_f, B2_a ... B2_c, B3_a ... B3_c for each load checking period T1 .

Therefore, the terminal selection unit 130 determines the load amount per a plurality of cells B1_a, B1_b, B1_f, B2_a, B2_c, B3_a ... B3_c, Based on the measurement information, a changing terminal is selected from the candidate terminals, i.e., terminals 1, 2, 3, 4,

Hereinafter, a process of selecting a changing terminal among the candidate terminals, that is, the terminals 1, 2, 3, 4, and 5, will be described in more detail.

First, the terminal selecting unit 130 selects a load based on the load amount per a plurality of cells (B1_a, B1_b ... B1_f, B2_a ... B2_c, B3_a ... B3_c) and the measurement information acquired by the information obtaining unit 120 And selects the candidate cell having the smallest load among the candidate cells according to the obtained measurement information.

As described above, the measurement information for the cell (B1_c) from the terminals 1, 3 and 4 and the measurement for the cell (B3_b) from the terminals 2 and 5 among the candidate terminals, If the information is obtained, the candidate cell according to the obtained measurement information will be the cell B1_c and the cell B3_b.

In this manner, the terminal selecting unit 130 grasps the candidate cells, that is, the cell B1_c and the cell B3_b, based on the measurement information obtained by the information obtaining unit 120. [

The terminal selecting unit 130 then selects a candidate cell, that is, the cell B1_c and the cell B1_b based on the load amount for each of the plurality of cells B1_a, B1_b, ... B1_f, B2_a ... B2_c, B3_a ... B3_c, B3_b), the candidate cell with the smallest load can be selected.

Of course, in addition to the above-described method, a variety of methods based on the load amount for a plurality of cells (B1_a, B1_b, ..., B1_f, B2_a ... B2_c, B3_a ... B3_c)

For example, the terminal selecting unit 130 selects a predetermined threshold load (for example, the number of active terminals <the third overload threshold, the third overload threshold (the third overload threshold), and the third overload threshold among the candidate cells, i.e., the cell B1_c and the cell B3_b, The first overload threshold value or the radio resource use amount fourth overload threshold value, and the fourth overload threshold value < second overload threshold value).

Accordingly, if both the cell B1_c and the cell B3_b are equal to or smaller than the critical load amount, the terminal selecting unit 130 can select all of them.

The terminal selecting unit 130 may then select a candidate cell having the smallest load among the cells B1_c and B3_b only if neither the cell B1_c nor the cell B3_b is below the critical load.

Hereinafter, it is assumed that the cell B1_c is selected from among the candidate cells, that is, the cell B1_c and the cell B3_b, according to the measurement information.

Then, the terminal selecting unit 130 selects a candidate terminal to which the measurement information for the selected candidate cell, that is, the cell B1_c, is reported as the above-mentioned candidate terminal, i.e., the terminal 1, 2, .

When the measurement information on the cell B1_c is acquired (reported) from the terminals 1, 3 and 4 among the candidate terminals, i.e., the terminals 1, 2, 3, 4 and 5 as described above , The terminal 1, 3, 4 reporting the measurement information on the cell B1_c among the terminals 1, 2, 3, 4, 5 is selected as the changing terminal.

As a result, the terminal selection unit 130 selects a candidate cell that has the best load condition among the candidate candidates that have been acquired (reported) from the candidate terminals, that is, the terminals 1, 2, As the changing terminal.

The control unit 140 handover the auxiliary cell (SCell) of the selected changing terminal to the candidate cell of the changing terminal from the specific cell when the changing terminal is selected by the terminal selecting unit 130. [

Here, the candidate cell of the changing terminal means the candidate cell having the smallest load among the candidate cells according to the measurement information acquired by the information acquiring unit 120 described above.

That is, in the case of the above-described example, the candidate cells of the terminals 1, 3 and 4 selected as the changing terminal are selected from the candidate cells according to the measurement information obtained (reported) from the candidate terminals 1, 2, And a cell B1_c which is a candidate cell having the smallest load.

When the terminal 1, 3, 4 is selected as the changing terminal, the control unit 140 sets the auxiliary cell (SCell) of the terminal 1, 3, 4 to the above-mentioned specific cell, (B1_c) of the terminals 1, 3 and 4 from the cell B 1 _b.

In this case, the base station apparatus 100 of the present invention is capable of transmitting only the CA terminals that can change the auxiliary cell (SCell) to the cell having the excellent load condition among the CA terminals using the overloaded cell as the auxiliary cell (SCell) The load of the auxiliary cell (SCell) of the CA terminal can be dispersed from the cell in the overload state by changing the handover of the auxiliary cell (SCell) of the CA terminal.

As a result, the base station apparatus 100 of the present invention does not change the auxiliary cell (SCell) of the CA terminal only in consideration of the position of the CA terminal but changes the overall load environment reflecting both the CA terminal and the CA- Load balancing in which the auxiliary cell (SCell) load of the CA terminal is distributed in a cell having excellent load condition is realized in consideration of the load.

As described above, according to the base station apparatus of the present invention, the load balancing of the auxiliary cell (SCell) of the CA terminal in consideration of the overall load environment of the base station is realized, and consequently, the communication of both the CA terminal and the CA non- The effect of improving the quality can be obtained.

Hereinafter, an operation method of the base station apparatus according to the preferred embodiment of the present invention will be described with reference to FIG. For convenience of description, reference will be made to the reference numerals of FIGS. 1 to 2 described above.

Here, the base station apparatus 100 provides a plurality of frequency bands, for example, a first frequency band B1, a second frequency band B2 and a third frequency band B3 as shown in Fig. 1, A plurality of cells B1_a, B1_b ... B1_f according to the first frequency band, cells B2_a ... B2_c according to the second frequency band, cells B3_a ... B3_c according to the third frequency band, &Lt; / RTI &gt;

The operation method of the base station apparatus 100 according to the present invention is characterized in that the load amount (B3_a) is calculated for each of a plurality of cells (B1_a, B1_b ... B1_f, B2_a ... B2_c, B3_a ... B3_c) (S100).

The operation method of the base station apparatus 100 according to the present invention includes a plurality of cells B1_a, B1_b, B1_f, B2_a, B2_c, B3_a, B1_f, B2_a, B2_c, B3_a ... B3_c of the plurality of cells (B1_a, B1_b, ..., B3_c) in the overloaded state (S110).

Hereinafter, for convenience of description, it is noted that the cell B2_b among the plurality of cells B1_a, B1_b, B1_f, B2_a, B2_c, B3_a ... B3_c is identified as a specific cell in the overload state I will explain it.

The method of operation of the base station apparatus 100 according to the present invention is a method of operating at least one cell that uses a cell B2_b as a spare cell SCell of a terminal connected to a cell B2_b, (S120).

To be more specific, a terminal connected to the cell B2_b is connected to a CA terminal (CA function activated, inactivated) connected by using the CA unsupported terminal connected to the cell B2_b and the cell B2_b as a basic cell PCell, , And the CA terminal (CA function activation) connected using the cell B2_b as the auxiliary cell SCell.

The method of operating the base station apparatus 100 according to the present invention is a method of operating the CA terminal (CA function activation) connected using the cell B2_b as the auxiliary cell SCell among the terminals connected to the cell B2_b , At least one candidate terminal can be selected.

The method of operating the base station apparatus 100 according to the present invention may select all the CA terminals (CA function activated) connected using the cell B2_b as the auxiliary cell SCell as the candidate terminal, (CA function activation) connected thereto by using the auxiliary cell (B2_b) as an auxiliary auxiliary cell (SCell), and may select randomly as a candidate terminal.

Hereinafter, for convenience of explanation, the terminals 1, 2, 3, 4, and 5 will be described as at least one selected candidate terminal.

The operation method of the base station apparatus 100 according to the present invention is a method for operating a plurality of cells B1_a, B1_b ... B1_f, B2_a ... B2_c , B3_a ... B3_c) of the candidate cell.

More specifically, the method of operating the base station apparatus 100 according to the present invention is a method of operating an A4 event policy including a preset threshold value (A4 threshold) and an A4 event in an rrcConnectionReconfiguration message to generate at least one candidate terminal, , 2, 3, 4, 5 (S130).

Accordingly, each of the terminals 1, 2, 3, 4, and 5 that have received the A4 event policy transmits the signal strength of the neighboring cell in addition to the cell B2_b used as the connected cell, that is, the auxiliary cell SCell, (For example, PCI, RSRP, RSRQ, etc.) to the base station apparatus 100 when the adjacent cell having the measured signal strength is equal to or greater than the threshold value (A4 threshold) thereby performing an operation of reporting the result.

In this case, the adjacent cell that measures the signal strength (e.g., RSRP, RSRQ) according to the A4 event policy includes the cell in the same frequency band as the cell B2_b used as the connected cell, that is, the auxiliary cell SCell And a cell of a frequency band different from that of the cell B2_b.

As described above, each of the terminals 1, 2, 3, 4, and 5 provided with the A4 event policy reports the measurement information about the adjacent cell that can be assigned (assigned and assigned) to the base station apparatus 100 via the A4 event )can do.

Accordingly, the method of operation of the base station 100 according to the present invention is a method in which measurement information on a neighboring cell reported according to the A4 event policy is transmitted from a candidate terminal, i.e., the terminals 1, 2, (Step S140).

Measurement information on the cell B1_c is obtained from the terminals 1, 3 and 4 among the candidate terminals, i.e., the terminals 1, 2, 3, 4 and 5, and measurement information on the cell B3_b Is obtained.

The operation method of the base station apparatus 100 according to the present invention may further include the steps of determining a load amount for each of the plurality of cells B1_a, B1_b, B1_f, B2_a, B2_c, B3_a ... B3_c, And selects a changing terminal from the candidate terminal based on the obtained measurement information.

More specifically, the method of operation of the base station apparatus 100 according to the present invention determines whether or not a load amount And a candidate cell having the smallest load among the candidate cells according to the obtained measurement information is selected based on the measurement information acquired in step S140.

As described above, the measurement information for the cell (B1_c) from the terminals 1, 3 and 4 and the measurement for the cell (B3_b) from the terminals 2 and 5 among the candidate terminals, If the information is obtained, the candidate cell according to the measurement information obtained in step S140 may be the cell B1_c and the cell B3_b.

As described above, the method of operating the base station apparatus 100 according to the present invention grasps candidate cells, i.e., the cell B1_c and the cell B3_b, based on the measurement information obtained in step S140.

The method of operation of the base station apparatus 100 according to the present invention may further include the steps of determining whether the number of cells B1_a, B1_b, B1_f, B2_a, B2_c, B3_a ... B3_c, It is possible to select a candidate cell having the smallest load among the candidate cells, that is, the cell B1_c and the cell B3_b.

Of course, in addition to the above-described method, a variety of methods based on the load amount for a plurality of cells (B1_a, B1_b, ..., B1_f, B2_a ... B2_c, B3_a ... B3_c)

Hereinafter, it is assumed that the cell B1_c is selected from among the candidate cells, that is, the cell B1_c and the cell B3_b, according to the measurement information.

The method of operation of the base station apparatus 100 according to the present invention is characterized in that the measurement information for the candidate cell selected in step S150, i.e., the cell B1_c, among the candidate terminals, i.e., the terminals 1,2,3,4,5, The candidate terminal is selected as the changing terminal (S160).

The operation method of the base station apparatus 100 according to the present invention is such that the measurement information on the cell B1_c from the terminals 1, 3 and 4 among the candidate terminals, i.e., the terminals 1, 2, 3, (Reporting), the terminal 1, 3, 4 reporting the measurement information on the cell B1_c among the terminals 1, 2, 3, 4, 5 is selected as the changing terminal.

As a result, the method of operation of the base station apparatus 100 according to the present invention is a method in which the best-loadable cells among the candidate candidates obtained (reported) from the candidate terminals, that is, the terminals 1, 2, ) Is selected as the changing terminal.

The method of operating the base station 100 according to the present invention handover the auxiliary cell (SCell) of the selected changing terminal from the aforementioned specific cell to the candidate cell of the changing terminal when the changing terminal is selected in step S160.

In other words, in the operation method of the base station apparatus 100 according to the present invention, when the terminals 1, 3 and 4 are selected as the changing terminals in step S160, the auxiliary cells SCell of the terminals 1, , It is possible to perform forced handover from the above-mentioned specific cell, that is, from the overloaded cell B2_b to the candidate cell of the terminal 1, 3, 4, that is, the cell B1_c (S170).

In this way, the method of operation of the base station apparatus 100 according to the present invention can be applied to a part of the CA terminal using the overloaded cell as the auxiliary cell (SCell), the auxiliary cell (SCell) The load of the auxiliary cell (SCell) of the CA terminal can be dispersed from the cell in the overloaded state by changing the handover of the auxiliary cell (SCell) of the CA terminal only to the CA terminal.

As a result, the method of operating the base station apparatus 100 according to the present invention is not limited to changing the auxiliary cell (SCell) of the CA terminal only in consideration of the position of the CA terminal, Load balancing in which the auxiliary cell (SCell) load of the CA terminal is dispersed in a cell having an excellent load condition in consideration of the environment, i.e., the load per cell is realized.

The operation method of the base station apparatus 100 according to the present invention can repeat the operation including the step S100 after the load confirmation period (T1) as long as the base station operation is not terminated (S180 No).

As described above, according to the method of operating the base station apparatus according to the present invention, the load balancing of the auxiliary cell (SCell) of the CA terminal in consideration of the overall load environment reflecting both the CA terminal and the CA non- The effect of improving the communication quality of both the CA terminal and the CA-supported terminal can be obtained as a result.

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 constructed 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 as defined by the appended claims.

According to the operation method of the base station apparatus and the base station apparatus according to the present invention, the load balancing of the auxiliary cell (SCell) of the CA terminal in consideration of the overall load environment of the base station is realized, It is not only the use of the related technology but also the possibility of commercialization or operation of the applied device is sufficient as well as it can be carried out clearly and practically, Invention.

10: Terminal
100: base station device
110: overload checking unit 120: information obtaining unit
130: Terminal selection unit 140:

Claims (8)

An overload checking unit for checking a specific cell in an overload state among the plurality of cells based on a plurality of cell load amounts;
An information obtaining unit obtaining at least one candidate terminal using the specific cell as a secondary cell, the measurement information for a candidate cell changeable among the plurality of cells;
And selecting a candidate cell among the candidate cells from which the measurement information is acquired based on the plurality of cell-by-cell load amounts and the measurement information and selecting a candidate terminal related to the specific candidate cell among the candidate terminals, Preceding Government; And
And a control unit for handing over the auxiliary cell of the changing terminal from the specific cell to the specific candidate cell. The method according to claim 1,
The information obtaining unit obtains,
To the at least one candidate terminal, a policy for reporting measurement information on a neighboring cell whose signal strength among neighboring cells other than the connected cell is greater than or equal to a predetermined threshold value to the base station apparatus,
And acquires measurement information for the neighboring cell reported from the at least one candidate terminal according to the policy, as measurement information for the changeable candidate cell. The method according to claim 1,
The terminal selection unit,
A candidate cell having the smallest load among the candidate cells according to the acquired measurement information is selected based on the plurality of cell-by-cell load amounts and the obtained measurement information,
Wherein the candidate terminal reporting the measurement information of the selected candidate cell among the at least one candidate terminal is selected as the changing terminal. The method according to claim 1,
Wherein the candidate cell of the changing terminal comprises:
And the candidate cell having the smallest load among the candidate cells according to the acquired measurement information. An overload checking step of identifying a specific cell in an overloaded state among the plurality of cells based on a plurality of cell load amounts;
An information obtaining step of obtaining measurement information on a candidate cell which can be changed among at least one candidate terminal using the specific cell as a secondary cell;
And selecting a candidate cell among the candidate cells from which the measurement information is acquired based on the plurality of cell-by-cell load amounts and the measurement information and selecting a candidate terminal related to the specific candidate cell among the candidate terminals, Selection stage; And
And a connection control step of handing over the auxiliary cell of the changing terminal from the specific cell to the specific candidate cell. 6. The method of claim 5,
Providing a policy to the at least one candidate terminal to report to the base station measurement information for a neighboring cell whose signal strength among adjacent cells other than the connected cell is greater than or equal to a predetermined threshold value;
The information acquiring step includes:
And acquires, as measurement information for the changeable candidate cell, measurement information for the neighboring cell reported from the at least one candidate terminal according to the policy. 6. The method of claim 5,
The terminal selection step includes:
A candidate cell having the smallest load among the candidate cells according to the acquired measurement information is selected based on the plurality of cell-by-cell load amounts and the obtained measurement information,
Wherein the candidate terminal reporting the measurement information of the selected candidate cell among the at least one candidate terminal is selected as the changing terminal. 6. The method of claim 5,
Wherein the candidate cell of the changing terminal comprises:
And the candidate cell having the smallest load among the candidate cells according to the acquired measurement information.

Images