KR101307468B1 - Method And Apparatus For Incentive-Based Association Control - Google Patents

Abstract

The present invention provides incentives for providing a predetermined resource to an intermediate access point that is closed to a specific user in a heterogeneous networks system including a macro base station and an intermediate access point. The present invention relates to a method and apparatus for performing communication by determining connection and performing access control accordingly.

Description

Incentive-based access control method and apparatus therefor {Method And Apparatus For Incentive-Based Association Control}

In the following description, a heterogeneous networks system including a macro base station and an intermediate access point may be provided in exchange for opening a predetermined resource to an intermediate access point that is closed to a specific user. The present invention relates to a method and apparatus for performing communication by determining an incentive and performing connection control accordingly.

Heterogeneous networks including macro base stations and intermediate access points have been developed and used to increase coverage and improve communication quality in shaded areas.

1 is a view for explaining the concept of a heterogeneous network.

A heterogeneous network includes one or more intermediate access points in addition to the conventional base station, and the conventional base station may be referred to as a macro base station or a macro eNB to distinguish from the intermediate access point. In addition, the intermediate access point may include a femto base station (Femto BS), an access point (AP), etc. In FIG. 1, these are collectively referred to as a remote radio head (RRH).

The macro base station and the intermediate access point (or RRH) may each be a transmission point (TP), and the terminal or user equipment may be directly connected to and serviced by the macro base station (for example, UE0), or each intermediate access point. Can be connected to and serviced (eg, UE1 and UE2).

In the heterogeneous network situation described above, the intermediate access points may be open to all user devices and may be used closed to only a specific user. As such, the intermediate access point operating in a closed manner may indirectly affect the user equipment serviced by the macro base station, and may have a problem in that the utility may be reduced in view of the entire network.

In the present invention, in the heterogeneous network system described above, an incentive to be provided in exchange for opening a predetermined resource to an intermediate access point closed to a specific user is determined, and accordingly, access control of the user equipment for the macro base station and the intermediate access point is performed. A method of performing communication and an apparatus therefor are provided.

According to an aspect of the present invention for solving the above problems, there is provided a method for performing a communication by the macro base station in a mobile communication system including a macro base station and an intermediate access point that is closed to a specific user. do. The method relates to a resource for allowing access to a device of a user other than the specific user determined based on information on an incentive to be provided when the intermediate access point allows access to a device of a user other than the specific user. And receiving information and controlling access to the intermediate access point of a device of a user other than the specific user based on information on a resource for allowing access to a device of a user other than the specific user.

In this case, the incentive may be proportional to the amount of resources allowing the intermediate access point to access a device of a user other than the specific user.

Further, the incentive to provide when the intermediate access point allows access to a device of a user other than the specific user may determine a factor according to the incentive provided to the intermediate access point in the overall throughputs of the user devices serviced by the macro base station. It may be updated in consideration of the macro cell utility corresponding to the deduction.

In addition, controlling access of the device of the user other than the specific user to the intermediate access point may include calculating an incentive for a specific associated state in the macro cell, and determining the macro cell utility according to the specific associated state and the calculated incentive. If the current macro cell utility according to the current association state is greater than the current macro cell utility according to the specific association state and the calculated incentive, update the current association state to the specific association state. It may be.

Alternatively, when any user device connected to the macro base station moves a connection to the intermediate access point, when the macro cell availability increases, the user device may be instructed to handover to the intermediate access point.

In addition, the intermediate access point may include a CSG femto base station (Closed Subscriber Group Femto BS), the CSG femto base station that allows access to the device of the user other than the specific user may correspond to the CSG-Open femto base station. .

In addition, a local white list may be provided to a device of a user other than the specific user based on information on resources for allowing access to a device of a user other than the specific user.

In addition, the intermediate access point may include a Home evolved Node B (HeNB) operating in a closed access mode, and the HeNB allowing access to a device of a user other than the specific user may be configured from the closed access mode. It can be switched to a hybrid access mode.

On the other hand, in an aspect of the present invention for solving the above problems is a method for performing the communication in the intermediate access point in a mobile communication system including a macro base station (Macro Base Station) and an intermediate access point closed to a specific user To provide. According to the present invention, when the intermediate access point permits access to a device of a user other than the specific user, a resource for allowing access to a device of a user other than the specific user determined based on information on incentives to be provided. Information about the macro base station, and a device of a user other than the specific user accesses the intermediate access point to perform communication using the resource.

Here, too, the incentive may be proportional to the amount of resources that allow the intermediate access point to access a device of a user other than the specific user.

In addition, a resource for allowing access to a device of a user other than the specific user may be determined in consideration of femtocell availability corresponding to a sum of factors of incentives provided to the intermediate access point with the overall throughput of the specific user's devices. .

In addition, the intermediate access point may include a CSG femto base station (Closed Subscriber Group Femto BS), the CSG femto base station that allows access to the device of the user other than the specific user may correspond to the CSG-Open femto base station. .

In addition, the intermediate access point may include a Home evolved Node B (HeNB) operating in a closed access mode, and the HeNB allowing access to a device of a user other than the specific user may be configured from the closed access mode. It may be switched to a hybrid access mode.

On the other hand, another aspect of the present invention for solving the above problems is proposed a macro base station (Macro Base Station) for performing communication in a mobile communication system including an intermediate access point that is closed to a specific user. The macro base station includes a transceiver for signal transmission and reception; And a processor connected to the transceiver to control signal transmission and reception of the transceiver, wherein the intermediate access point is determined based on information on incentives to be provided when the intermediate access point permits access to a device of a user other than the specific user. When the transceiver receives information on a resource that allows access to a device of a user other than the specific user,

The processor is configured to control access of a device of a user other than the specific user to the intermediate access point based on information on a resource allowing access to a device of a user other than the specific user.

In this case, the processor may be configured to update the incentive in consideration of the macro cell efficiency corresponding to the subtraction of the factor according to the incentive provided to the intermediate access point in the sum of the throughputs of the user equipments serviced by the macro base station.

In addition, another aspect of the present invention for solving the above problems is to perform a communication in a mobile communication system including a macro base station (Macro Base Station), and provides an intermediate access point that is closed to a specific user . The macro base station includes a transceiver for signal transmission and reception; And a processor connected to the transceiver to control signal transmission and reception of the transceiver, wherein the processor is configured to provide information on incentives to be provided when the intermediate access point allows access to a device of a user other than the specific user. Determine information on a resource allowing access to a device of a user other than the specific user, and provide information on a resource allowing access to a device of a user other than the specific user to the macro base station through the transceiver. And a device of a user other than the specific user is connected to the intermediate access point to perform communication using the resource.

In this case, the processor may be configured to determine a resource for allowing access to a device of a user other than the specific user in consideration of the sum of the throughputs of the devices of the specific user plus a factor according to an incentive provided to the intermediate access point. .

According to the present invention as described above, the intermediate connection points that operate selfishly can also open resources for increasing their usefulness, thereby increasing overall macro cell utility.

1 is a view for explaining the concept of a heterogeneous network.
2 is a view for explaining a configuration diagram of a heterogeneous network system to which a femto base station is added.
3 and 4 are diagrams for explaining the concept of incentive-based access control according to an embodiment of the present invention.
5 is a view for explaining an incentive-based association control scheme according to an embodiment of the present invention.
6 is a view for explaining an incentive-based association control scheme according to another embodiment of the present invention.
7 is a view for explaining an incentive-based association control scheme according to another embodiment of the present invention.
8 is a diagram illustrating a scheduling scheme by a femto base station when association control is performed according to an embodiment of the present invention.
9 is a diagram illustrating a macro / femto base station or terminal device structure according to an embodiment of the present invention.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description, together with the accompanying drawings, is intended to illustrate exemplary embodiments of the invention and is not intended to represent the only embodiments in which the invention may be practiced. The following detailed description includes specific details in order to provide a thorough understanding of the present invention. However, those skilled in the art will appreciate that the present invention may be practiced without these specific details.

In some instances, well-known structures and devices may be omitted or may be shown in block diagram form, centering on the core functionality of each structure and device, to avoid obscuring the concepts of the present invention. In the following description, the same components are denoted by the same reference numerals throughout the specification.

In addition, in the following description, it is assumed that a user device collectively refers to a mobile or fixed user terminal device such as a UE, a mobile station (MS), and an advanced MS (AMS). In addition, it is assumed that the macro base station collectively refers to any node of the network side that communicates with the terminal, such as a Node B, an eNode B, and a Base Station, which are separated from the intermediate access point. In addition, it is assumed that the intermediate access point collectively refers to femto BS, AP, pico BS, etc., unless a special example is described.

First, the above-described invention will be described with an example of an intermediate access point being a femto base station for convenience of description. In this regard, we first look at femtocells.

With the rapidly increasing amount of wireless communication, the demand for high data rates is increasing. In recent years, femtocells have gained much attention as an alternative to increase the reuse of frequency resources and increase the capacity of systems in wireless network environments. Unlike macro base stations, which are elaborately deployed by mobile operators, femto base stations tend to be unspecified and densely distributed because they are deployed or moved by users. The distribution of dense and unspecified femto base stations results in cell link interference being compromised by not only users at cell coverage boundaries but even macro terminals near their femto base stations, and a large proportion of users are exposed to cell interference. do.

In addition, since femto base stations allow access only to terminals belonging to a closed subscriber group (CSG) by default, it is difficult for terminals to receive services from a base station that provides better link quality through handover. Increase link quality degradation.

2 is a view for explaining a configuration diagram of a heterogeneous network system to which a femto base station is added.

As shown in FIG. 2, the wireless communication system to which the femto base station is added includes a femto base station 110, a macro base station 120, a femto network gateway (FNG) 130, and an access service network. (access service network, hereinafter referred to as "ASN") 140 and connectivity service network (hereinafter referred to as "CSN") 150. The macro base station 120 refers to a general base station of a conventional wireless communication system.

The femto base station 110 is a compact version of the macro base station 120 and performs most of the functions of the macro base station. The femto base station 110 directly connects to a transmission control protocol / internet protocol (TCP / IP) network and operates independently like the macro base station 120, and has a coverage of about 0.1 to 30 m, and one femto base station 110 is accommodated. There are about 10 to 20 terminals. The femto base station 110 may use the same frequency as the macro base station 120 or may use another frequency.

The femto base station 110 may be connected to the macro base station 120 through an R1 interface to receive a downlink channel of the macro base station 120, and the femto base station 110 may control a control signal to the macro base station 120. signal) can be sent.

The femto base station 110 may cover an indoor or shadowed area that the macro base station 120 does not cover, and may support high data transmission. The femto base station 110 may be installed in an overlay form in the macro, or may be installed in a non-overlay form in an area not covered by the macro base station 120.

The femto base station 110 may be classified into two types. The first type is a closed subscriber group (CSG) femto base station, and the second type is an open subscriber group (OSG) femto base station. The CSG femto base station groups the terminals accessible to it and grants a CSG ID (identification), and only the terminal to which the CSG ID is assigned can access the CSG femto base station. The OSG femto base station is a base station to which all terminals can access. On the other hand, some of the femto base station 110 described above basically operates as a CSG femto base station, but in a hybrid access mode (Hybrid Access Mode) to allow the use of resources to non-subscribers in a line that guarantees QoS for their subscribers It may work.

Meanwhile, the FNG 130 is a gateway for controlling the femto base station 110 and is connected to the ASN 140 and the CSN 150 through the Rx interface and the Ry interface. The femto base station 110 may receive a service from the CSN 150 through the FNG 130, and the terminal connected to the femto base station 110 may provide functions such as authentication and IMS to the FNG 130 or the CSN 150. You can get the service from. The CSN 150 provides a terminal with a connection of an application service such as the Internet, VoIP, and the like, and provides an authentication and charging function, and the ASN 140 controls the macro base station 120 and the macro base station 120 and the CSN 150. Manages connections.

In the following description, a terminal serviced by a macro base station among terminals is referred to as a macro UE (MUE), and a terminal serviced by a femto base station is referred to as a femto UE (FUE).

3 and 4 are diagrams for explaining the concept of incentive-based access control according to an embodiment of the present invention.

Originally, the problem of associating a macro base station or a femto base station with a UE was an assumption of an open femto base station operated by a macrocell operator. However, in a real environment, femto base stations installed by not only operators of the macro cell but also other companies within the coverage of the macro cell, and femto base stations purchased and installed and operated by users are mixed. As such, the femto base station purchased and installed / operated by another operator / user has no reason to open resources to the MUE, so it is likely to operate selfishly, and may cause interference to the MUE in some cases.

The present invention proposes incentives to femto base stations operated by macro base stations and other users in such an environment, thereby inducing their opening, sharing some of the radio resources of the femto base stations, and solving the interference problem of the femto base station to the MUE, It is proposed a method of balancing the load of the base station.

To this end, as shown in FIG. 3, the macro base station 301 may provide incentives to the femto base station 302 operating in a closed manner (i.e., operating in CSG mode) for a specific user when allowing access to MUEs. ('C' in FIG. 3) may be considered. The incentive may be a direct radio resource fee payment to the femto base station owner or a fee reduction for the use of the femto base station, but is not limited thereto. In addition, the following incentives assume that the femto base station is proportional to the amount of resources (eg, bandwidth) that allows the MUE to access. For example, if the bandwidth allocated to the MUE by the femto base station 302 is π , it is assumed that the incentive (or increase in the efficiency of the femto base station) becomes 'c * π '.

Accordingly, as shown in FIG. 3, the femto base station 302 may allow access to the general MUE as well as the FUE in its CSG list, and may allocate resources.

Meanwhile, in the embodiment of the present invention, it is assumed that the roles of the macro base station and the femto base station are divided as shown in FIG. 4.

Referring to FIG. 4, the macro base station may determine incentives (c1-cf) to be provided when each femto base station (Femto BS 1-Femto BSf) allows access to a device of a user other than its subscriber. Preferably, this incentive may be an incentive per bandwidth that each femto base station opens.

Based on the incentive information (c1-cf) determined in this way, each femto base station can determine the bandwidth ( π ₁ - π _f ) to allow access to the MUE not subscribed to it.

Both the macro base station and the femto base stations may include a scheduler to allocate resources to the UEs associated with them, and as mentioned above, the femto base station that has decided the bandwidth to open to the MUE not subscribed to itself is based on the MUE. And a resource assigned to the FUE subscribed to it.

In addition, as shown in FIG. 4, the macro base station may include an association control entity. As described above, the associated control entity may determine whether each UE performs handover from the macro base station to the femto base station based on a bandwidth ( π ₁ - π _f ) to allow access to the MUE determined by each femto base station. have.

3 and 4 will be described in more detail with respect to the algorithm for determining the bandwidth to allow the femto base station to access the MUE according to the information (c) for the incentive.

First, one embodiment of the present invention proposes to define its utility as follows from the perspective of a femto base station.

In Equation 1, I _f denotes a set of UEs (FUEs) subscribed to a femto base station f, Ri denotes an average throughput of UE i, and π _f denotes a bandwidth for opening a FUE from a femto base station f to MUE, cf represents incentives per bandwidth. And β represents an arbitrary coefficient.

In Equation 1, the front end represents a condition in which the log sum of the throughputs of the FUEs of the corresponding femto base station is maximized, and the rear end represents the degree of incentive according to the degree to which the corresponding femto base station opens bandwidth to the MUEs. The form connected by β is shown. In the case of using the utility defined in this way, the CSG femto base station can determine the bandwidth maximizing the above-mentioned utility and provide it to the MUE. Hereinafter, the utility as shown in Equation 1 is expressed as Uf.

The following constraints are assumed to determine the bandwidth maximizing the utility by using the above definition of utility.

In Equation 2, qi represents a minimum required throughput. i represents any i in If.

In the above equation, Wf represents the available bandwidth of the femto base station f.

In Equation 4, Zf represents the number of FUEs belonging to the femto base station f, and it is assumed that the average throughput is calculated by subtracting a bandwidth open to the MUE in the entire bandwidth.

Substituting the constraints of Equations 2 to 4 into the utility definition of Equation 1 and arranging, the following conclusions were drawn.

Equation (5) preferably does not open bandwidth to the MUE when the incentive cf is less than or equal to the first reference value, and each of the incentives cf is greater than the first reference value but less than or equal to the second reference value, and greater than the second reference value, respectively. It specifies the bandwidth to open to the MUE.

Meanwhile, hereinafter, an algorithm for determining an optimal incentive for the macro base station will be described. In one embodiment of the present invention, the optimal incentive for the macro base station may be based on the information about the bandwidth to be opened for each femto base station as described above. To this end, it is preferable that each femto base station reports to the macro base station the bandwidth information determined to be opened through the utility concept based on Equation (1).

In one embodiment of the present invention, the utility of the macro base station is proposed to be defined as follows.

The macro base station has its utility depending on the incentive provided to the femto base station serving the MUE and the association state of the MUEs. In Equation 6, x denotes an association indicator of the MUE, and hereinafter, MUE i will be represented as x _{M, i} , x _{f, i} depending on whether it is associated with the macro base station or the femto base station. In Equation 6, I _M represents a set of MUE.

In Equation 6, the front end represents the log sum of throughputs of the MUEs, and the rear end represents the utility spent by providing an incentive to the femto base station. And these two are assumed to be connected by arbitrary coefficient β.

In the present embodiment, the utility of the macro cell is expressed as the expenditure due to the sum and incentive of the utility of the MUEs as shown in Equation 6 above, and the macro base station is associated with an optimal association state (matrix X) and a corresponding association state to maximize the utility. Suppose we determine the optimal incentive (vector C) in.

Consider the following constraints in the determination.

Equation (7) indicates that the sum of the association indicators for all UEs should be one.

In Equation 8, Y _M represents the number of MUEs associated with the macro base station.

In Equation 9, Y _f represents the number of MUEs associated with a femto base station according to the scheme according to the present embodiment.

In Equation 10, W _M represents the bandwidth of the macro base station, and Equation 10 indicates that the average throughput of the MUEs is increased not only by the bandwidth of the macro base station but also by the frequency provided by the femto base station according to the present embodiment. .

By substituting the constraints of Equations 7 to 10 into the utility definition of Equation 6, it is proposed to calculate the following association control and an optimal incentive per bandwidth.

는 다음과 같이 정의하는 것을 가정하였다.In Equation (11)

Assumes the following definition:

In the following description, an association control algorithm that can be used by the macro base station according to the present invention will be described. As an embodiment of the present invention, the following two algorithms are proposed.

Tables 1 and 2 show examples of algorithms that can be used to perform associative control based on an optimal per-band incentive for each femto base station determined by Equation 6 in the macro base station.

According to Table 1, an optimal per-bandwidth incentive is calculated for each target association state X, and when the macro cell utility according to the calculated incentive and association state is greater than the preset macro cell utility, the preset macro cell utility Update algorithm and an association control to the target association state.

Offline algorithms for finding such optimized results (associated control states and incentives) can be less useful due to high computational complexity.

는 매크로 유저 k 를 매크로 기지국으로부터 펨토 기지국 f 로 핸드오버 시키며, 그때의 연관상태에 대응되는 최적의 인센티브를 f 에게 제공할 때 증가하게 되는 매크로기지국의 효용을 나타낸다. 마찬가지로,

는 펨토셀 f로부터 서비스를 받던 매크로 유저 k 를 매크로 기지국으로 핸드오버 시킬 때 증가하게 되는 매크로 기지국의 효용을 나타낸다.Therefore, we propose an on-line algorithm as shown in Table 2, which can operate in real time with low computational complexity even though it does not always find an optimal result. In Table 2

Denotes the utility of the macro base station to be increased when handing the macro user k from the macro base station to the femto base station f and providing f with an optimal incentive corresponding to the association state at that time. Likewise,

Denotes the utility of the macro base station, which is increased when handing over a macro user k received from the femtocell f to the macro base station.

In the above-described embodiments, the subject that determines the incentive and performs the association control has been described as a macro base station, but the FNG 130 and the like shown in FIG. 2 perform this in accordance with the specification of the architecture including the femto base station. You may. In addition, as described above, the above-described scheme may be applied to a heterogeneous network including a femto base station as well as a heterogeneous network including any other intermediate access point.

Hereinafter, an incentive-based association control method according to each embodiment of the present invention will be described based on the above-described concept.

5 is a view for explaining an incentive-based association control scheme according to an embodiment of the present invention.

First, when the femto base station permits access to the MUE, the femto base station may determine a resource for allowing access to the MUE based on information on incentives to be provided (S501). In this case, the femto base station may determine a resource allowing the access using the femtocell availability concept considering not only the sum of throughputs of the FUE but also an incentive according to the amount of resources to be provided to the MUE as shown in Equation 1 above. The bandwidth information thus determined may be delivered to the macro base station (S502).

Upon receiving such bandwidth information, the macro base station may perform association control and incentive optimization of MUEs based on the received information (S503). The optimal incentive is preferably determined using the macrocell utility defined as in Equation 6 above. In addition, as for the association control of MUEs, the algorithm of Table 1 or Table 2 may be used.

For example, when the algorithm of Table 2 is used, it is determined whether handing over a specific MUE to a femto base station results in an increase in macrocell efficiency, and according to this determination, results in an increase in macrocell efficiency. A handover instruction may be transmitted to the user (S504). Accordingly, the MUE may request access to the femto base station (S505), and the femto base station may allow access of the MUE through the bandwidth determined in step S501 described above (S506).

A femto base station operating in accordance with the embodiments described above may be referred to as a CSG-Open femto base station that allows connection to a non-subscriber of a CSG femto base station in certain cases. This can be contrasted with the CSG-Closed femto base station, which allows non-subscriber access only in emergency situations.

In addition, in a 3GPP LTE-based system, a femto base station may be referred to as a HeNB (Hone eNB), and a femto base station operating according to the above embodiments may correspond to a HeNB operating in a mixed access mode. That is, the HeNB according to the present embodiments can switch from the closed mode to the mixed connection mode by opening a constant bandwidth to the MUEs.

6 is a view for explaining an incentive-based association control scheme according to another embodiment of the present invention.

In FIG. 5 and the above-described embodiments, it is assumed that the femto base station first determines the bandwidth to open to the MUE, and the macro base station updates the incentive and performs the association control based on the bandwidth information determined by the femto base station. However, in another embodiment of the present invention, the macro base station first provides information on the incentive to the femto base stations, and after the femto base station receives such incentive information, it considers a mechanism for determining the bandwidth to open to the MUE. Specifically, in the present embodiment, the macro base station may be in the form of predicting a bandwidth to be opened to the MUE by the femto base station according to the incentive provided per bandwidth, and determining an incentive to be provided per bandwidth based on the prediction.

In this embodiment, the macro base station may first determine an incentive per bandwidth that the femto base station will open to the MUE according to the above-described embodiments (S601). In this case, the determination of the incentive may use a macrocell utility concept defined as in Equation 6 above. The information on the bandwidth that the femto base station will open to the MUE may use the bandwidth information that the femto base station opens to the MUE at this stage, may use a preset bandwidth level, or predict the bandwidth that the femto base station will open according to other information. have. The determined incentive (C) information may be delivered to the femto base station (S602).

Upon receiving the incentive information, the femto base station may determine the bandwidth to open to the MUE based on this (S603). Determination of the open bandwidth of the femto base station may use the concept of the utility of the femto base station defined as in Equation 1 above. The bandwidth information thus determined may be transferred back to the macro base station (S604).

The macro base station that has received the bandwidth information to open to the MUE from the femto base station may perform the association control of the UE accordingly. Of course, at this stage, the macro base station may update the incentive information again.

In detail, the macro base station that has received the bandwidth information to be opened to the MUE from the femto base station may perform the association control through the algorithm described above with respect to Table 1 or Table 2 based on this. For example, when using the online algorithm shown in Table 2, when it is determined that the increase in the macrocell efficiency is maximized when a specific MUE is handed over to the femto base station, the handover indication may be transmitted to the corresponding MUE (S6O6). Upon receiving the handover instruction, the MUE may transmit an access request to the corresponding femto base station (S606), and the femto base station may allocate a bandwidth determined to open to the MUE to the MUE and transmit a response message for the access (S607). ).

7 is a view for explaining an incentive-based association control scheme according to another embodiment of the present invention.

5 and 6, only the network initiated handover, in which the macro base station determines a handover decision of the MUE and transmits a handover indication to the MUE, is considered. However, in the association control according to the present invention, each MUE may also initiate a handover to the CSG femto base station, and FIG. 7 will be described in consideration of such an embodiment.

Steps S601 to S604 in FIG. 7 are the same as those in FIG. 6. That is, the macro base station determines the incentive, and the femto base station can determine the bandwidth to open to the MUE based on this. However, as shown in FIG. 5, the femto base station first determines the bandwidth to open to the MUE, and the same may be applied to the case where the macro base station determines the incentive based on the same. Hereinafter, it is assumed that both cases are considered. do.

In the present embodiment, the macro base station that receives bandwidth information to be opened to the MUE from the femto base station may update the MUE white list allowing access to each MUE based on the received information (S701). The original MUE white list is information on an identifier (ID) list of femto base stations that allow access to the corresponding MUEs. CSG femto base stations to which the corresponding MUE is not subscribed are not included in this MUE white list. However, according to an embodiment of the present invention, the macro base station that has received the information about the CSG femto base station that has decided to open a predetermined bandwidth to the MUE may include the CSG femto base station (CSG femto base station ID) in the white list of the corresponding MUE. have. The updated MUE white list is transmitted to the MUE (S702), so that the corresponding MUE can obtain a femto base station list allowed to access the MUE.

On the other hand, as another example, the macro base station may separately generate and transmit a list of CSG femto base stations determined to open according to the present invention among CSG femto base stations to which the corresponding MUE is not subscribed separately from the white list of the conventional MUE. Receiving such information, the MUE may attempt to access the femto base station list according to the conventional classification and the femto base station list determined to open according to the present invention.

The above-described MUE white list may be based on the geographic location information of the corresponding MUE. Accordingly, the MUE white list may additionally include location information of the MUE.

In this way, the MUE having secured the femto base station list to which it can access may initiate a terminal induction handover procedure (S703). That is, the MUE transmits a handover request message to the macro base station, and based on this, the handover procedure may be performed by sending the handover indication message to the MUE.

Of course, in the above-described embodiment, the handover may be performed by the network-induced handover.

Meanwhile, hereinafter, a method of performing scheduling in a corresponding femto base station after association control is performed according to the embodiments as described above will be described.

8 is a diagram illustrating a scheduling scheme by a femto base station when association control is performed according to an embodiment of the present invention.

Each femto base station can schedule FUE and MUE based on its open bandwidth ( π ). Scheduling can be performed in the secondary domain, which consists of a time axis and a frequency axis. In the present embodiment, for convenience of explanation, only resource division in the time axis (TDMA-time division multiple access) is described, but in the time-frequency axis The same case may be described in the case of dividing the bandwidth.

Referring to FIG. 8, FIG. 8 illustrates an example of scheduling three femto-users and two macro-users by applying an open bandwidth determined by a femto base station. There is a method (periodic) to apply the determined open bandwidth in each resource allocation frame (upper right corner of FIG. 8), and in each frame, even if the resource allocation is not performed according to the ratio of open bandwidth, the resources are allocated according to the ratio of open bandwidth in the long term. There is a without period (bottom right of FIG. 8).

At the same time, opportunistic scheduling (right interruption in FIG. 8) can be applied to obtain multi-user gains in a channel environment that varies over time (or frequency) while maintaining an open bandwidth determined over time. It is proposed to select a UE for each slot as a reference.

는 펨토 기지국이 개방하기로 결정한 대역폭이고,

는 현재 슬롯까지의 평균 개방 대역폭을 나타낸다. θ는

과

의 차이를 반영하기 위한 파라미터이고, 펨토 유저들의 경우 1로 설정함으로써, 기존 비례공평스케쥴링 방법과 동일한 메트릭(metric)을 적용할 수 있다. 아래 수학식 14는 매 슬롯마다 UE들의 이동평균 전송률을 갱신하는 방법을 나타낸 것이다.In Equation 13

Is the bandwidth that the femto base station decides to open,

Denotes the average open bandwidth up to the current slot. θ is

and

This parameter reflects the difference of, and by setting it to 1 for femto users, the same metric as the existing proportional fair scheduling method can be applied. Equation 14 below shows a method of updating the moving average data rates of UEs in each slot.

Hereinafter, an apparatus of a macro base station, a femto base station, and a terminal for performing incentive-based access control according to the embodiments as described above will be described.

9 is a diagram illustrating a macro / femto base station or terminal device structure according to an embodiment of the present invention.

The macro / femto base station or terminal device 800 according to an embodiment of the present invention may include a transmitting module 840, a receiving module 810, and a processor 820. The transmitting module 84 and the receiving module 810 may be physically implemented in the form of a transceiver, but need not be limited thereto.

Meanwhile, the apparatus 800 according to an embodiment of the present invention stores the incentive determination algorithm, the open bandwidth determination algorithm, the association control algorithm as described above, and the memory 830 for temporarily storing the received information according to the situation. It may further include.

When the apparatus 800 of FIG. 9 is a macro base station, the processor 820 may allow an intermediate access point (eg, a femto base station) to access a device (eg, MUE) of a user other than a specific user. When receiving information about a resource allowing access to a device of a user other than the specific user determined based on the information on the incentive to be provided through the transceiver (or the receiving module 810), The device may be configured to control access to the intermediate access point by a device of a user other than the specific user based on information on a resource for allowing access to the device.

In addition, the memory module 830 may store the macro cell utility information (or each of the factors) corresponding to the subtraction of the factor according to the incentive provided to the intermediate access point from the sum of the throughputs of the user equipments serviced by the macro base station. In addition, the processor 830 may be configured to update the incentive in consideration of the macro cell utility.

Meanwhile, when the apparatus 800 of FIG. 9 is an intermediate access point (for example, a femto base station), the processor 820 may provide information about incentives to be provided when the intermediate access point allows a device of a user other than a specific user. Determine information on a resource that allows access to a device of a user other than the specific user based on the transceiver, and transmit / receive information about a resource that allows access to a device of a user other than the specific user (for example, a transmission module) And a device of a user other than the specific user to access the intermediate access point and perform communication by using the resource (840).

Further, the memory 830 may store a factor according to the sum of throughputs of the devices of the specific user and / or an incentive provided to the intermediate access point, and the processor 830 may store the intermediate value in the sum of throughputs of the devices of the specific user. It may be configured to determine a resource to allow access to the device of the user other than the specific user in consideration of the sum of the factors according to the incentive provided to the access point.

The detailed description of the preferred embodiments of the invention disclosed as described above is provided to enable any person skilled in the art to make and practice the invention. While the above has been described with reference to preferred embodiments of the present invention, those skilled in the art will understand that various modifications and changes can be made without departing from the scope of the present invention. For example, those skilled in the art can use each configuration described in the above embodiments in a manner that combines with each other.

Accordingly, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Embodiments of the present invention as described above may be used in the same manner in various mobile communication systems in which an intermediate access point such as a femto base station as well as a 3GPP LTE system may be used.

Claims (21)

In the mobile communication system comprising a macro base station (Macro Base Station) and an intermediate access point that is closed to a specific user, the method of the macro base station to perform the communication,
Receiving information on a resource allowing access to a device of a user other than the specific user determined based on information on an incentive to be provided when the intermediate access point permits access to a device of a user other than the specific user and,
And controlling access to the intermediate access point by a device of a user other than the specific user based on information on a resource allowing access to a device of a user other than the specific user. The method of claim 1,
And wherein the incentive is proportional to the amount of resources the intermediate access point allows access to a device of a user other than the particular user. 3. The method of claim 2,
The incentive to provide when the intermediate access point allows a device of a user other than the specific user,
And updating in consideration of macro cell availability corresponding to subtracting a factor according to an incentive provided to the intermediate access point in total throughputs of user equipments serviced by the macro base station. The method of claim 3, wherein
Controlling a device of a user other than the specific user from connecting to the intermediate connection point,
Calculate incentives for specific association states within macro cells,
If the macro cell utility according to the specific association state and the estimated incentive is greater than the current macro cell utility according to the current association state, the macro cell utility according to the particular association state and the calculated incentive And adjust the current association state to the specific association state. The method of claim 3, wherein
If any user equipment connected to the macro base station moves the connection to the intermediate access point, when the macro cell availability increases, instructing the user equipment to handover to the intermediate access point; . The method of claim 1,
Wherein the intermediate access point comprises a Closed Subscriber Group Femto BS. The method according to claim 6,
The CSG femto base station that allows access to a device of a user other than the specific user corresponds to the CSG-Open femto base station, the communication method of the macro base station. The method of claim 1,
And providing a local white list to a device of a user other than the specific user based on information on resources for allowing access to a device of a user other than the specific user. The method of claim 1,
Wherein the intermediate access point comprises a Home evolved Node B (HeNB) operating in Closed Access Mode. The method of claim 9,
A HeNB that allows access to a device of a user other than the specific user is switched from the closed access mode to a hybrid access mode. In the mobile communication system including a macro base station (Macro Base Station) and an intermediate access point that is closed to a specific user, the method of performing the communication in the intermediate access point,
When the intermediate access point permits access to a device of a user other than the specific user, the information on resources for allowing access to a device of a user other than the specific user determined based on the information on incentives to be provided. To the macro base station,
And a device of a user other than the specific user accesses the intermediate access point to perform communication using the resource. The method of claim 11,
And wherein the incentive is proportional to the amount of resources that the intermediate access point allows access to a device of a user other than the specific user. The method of claim 11,
A resource that allows access to a device of a user other than the specific user,
And determining femtocell availability corresponding to the sum of the factors according to incentives provided to the intermediate access point for the overall throughput of the devices of the particular user. The method of claim 11,
And the intermediate access point comprises a closed subscriber group femto base station (CSG). 15. The method of claim 14,
The CSG femto base station that allows access to a device of a user other than the specific user corresponds to a CSG-Open femto base station, communication method of the intermediate access point. The method of claim 11,
And the intermediate access point comprises a Home evolved Node B (HeNB) operating in a closed access mode. 17. The method of claim 16,
A HeNB that allows access to a device of a user other than the specific user is switched from the closed access mode to a hybrid access mode. In a macro base station performing a communication in a mobile communication system including an intermediate access point closed to a specific user,
A transceiver for transmitting and receiving a signal; And
A processor connected to the transceiver to control signal transmission and reception of the transceiver,
When the intermediate access point permits access to a device of a user other than the specific user, the information on the resource for allowing access to the device of the user other than the specific user determined based on the information on the incentive to be provided. If the transceiver is receiving,
And the processor is configured to control access to the intermediate access point of a device of a user other than the specific user based on information on a resource allowing access to a device of a user other than the specific user. The method of claim 18,
And the processor is configured to update the incentive in consideration of macro cell availability corresponding to subtracting a factor according to an incentive provided to the intermediate access point in a sum of throughputs of user equipments serviced by the macro base station. In an intermediate access point that performs communication in a mobile communication system including a macro base station and is closed to a specific user,
A transceiver for transmitting and receiving a signal; And
A processor connected to the transceiver to control signal transmission and reception of the transceiver,
The processor may provide information on a resource allowing access to a device of a user other than the specific user based on information on an incentive to be provided when the intermediate access point allows access to a device of a user other than the specific user. Determine, and provide information about a resource allowing access to a device of a user other than the specific user to the macro base station through the transceiver, and a device of a user other than the specific user accesses the intermediate access point. Intermediate access point, characterized in that configured to perform communication using. 21. The method of claim 20,
And the processor is configured to determine a resource allowing access to a device of a user other than the specific user in consideration of the sum of the throughputs of the devices of the specific user plus a factor according to an incentive provided to the intermediate access point.

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