KR20100068162A - Apparatus and method for controlling inter-cell interference - Google Patents

Abstract

PURPOSE: An inter-cell interference control device and a method thereof are provided to efficiently evade or relax the inter-cell interference by using fractional frequency reusing technology. CONSTITUTION: An obtaining unit(501) obtains the information about the resources used in a serving cell and a neighboring cell. A decision unit(502) divides the serving cell into one or more areas, designs the resources as area, and authorizes the interference property about each resources. A controlling unit(503) uses the designated resources and interference characteristic according to the location of the terminal within the serving cell in order to perform the resource allocation scheduling or the resources power management.

Description

Apparatus and method for controlling inter-cell interference}

Relates to mobile communication technology. More specifically, it relates to techniques for mitigating intercell interference in mobile communication systems.

The present invention is derived from the research conducted as part of the IT growth engine technology development project of the Ministry of Knowledge Economy and the Ministry of Information and Communication Research and Development. [Task management number: 2006-S-003-03, Task name: Development of next generation mobile communication service platform] .

Recently, discussions on technologies to be proposed for 4G mobile communication have been actively conducted. In particular, technologies such as expansion of transmission bandwidth, improved multi-antenna technology, uplink capacity improvement, and inter-cell interference mitigation are being discussed. Inter-cell interference mitigation techniques include small microcells to support high frequencies, femtocells installed in buildings or private areas to provide high data rates for specific users, and wireless to cell edge areas to increase base station coverage. The importance is increasing in the 4th generation mobile communication where a relay or the like will be installed.

As such, the presence of various cells having a small service area increases the cell overlapping area which is highly influenced by the inter-cell interference, and a technology for controlling inter-cell interference has become an essential technology for improving data efficiency of the system.

Soft frequency reuse technology (SFR) is a technology that can increase the data transmission of the terminal that is located at the cell boundary and the interference of the neighboring cell a lot. This is a generalization of the fractional frequency reuse (FFR) technology. By setting the transmit power of each subband differently, neighboring cells are located at the cell boundary and can increase the data transmission rate of the UE which is frequently affected by neighboring cells. It is a skill.

Using frequency reuse index 1, all cells use the same frequency, resulting in greater inter-cell interference. However, the maximum reuse of frequencies results in high overall system efficiency. On the other hand, increasing the frequency reuse index reduces inter-cell interference but causes a high frequency waste.

Disclosed herein is an apparatus and method for intercell interference coordination that can mitigate or adjust intercell interference by complementing a partial frequency reuse technique.

The apparatus and method according to an aspect of the present invention may divide a cell into a plurality of regions. An area of a cell may be divided into a central area and a peripheral area, and the peripheral area may be divided into an area adjacent to another cell and an area that is not.

In addition, the apparatus and method according to an aspect of the present invention may determine the resources to be allocated for each divided area. If resources are defined in logical physical resource block units, it is possible to designate specific physical resource blocks for each region. In addition, there may be a physical resource block that is always available and optionally available.

In addition, the apparatus and method according to an aspect of the present invention can determine the interference characteristic for each resource for each region. When a plurality of specific physical resource blocks in a region are designated, it is possible to give different interference characteristics to each physical resource block according to the possibility of interference and the possibility of interference avoidance.

In addition, the apparatus and method according to an aspect of the present invention can perform resource allocation scheduling in consideration of resources specified for each region and interference characteristics applied for each resource. If a plurality of specific physical resource blocks in a region are designated and different interference characteristics are assigned to each physical resource block according to the possibility of interference and the possibility of interference avoidance, the physical resource blocks with less likely to cause interference are allocated first. It is possible to do scheduling.

In addition, the apparatus and method according to an aspect of the present invention can perform power management in consideration of resources specified for each region and interference characteristics applied for each resource. When a plurality of specific physical resource blocks are specified in a region and different interference characteristics are given to each physical resource block according to the possibility of interference and the possibility of avoiding interference, the physical resource block having the least possibility of interference has a maximum power limit. It is possible to set high.

In addition, the apparatus and method according to an aspect of the present invention may separately define a part of a resource to be used in various ways to use it for a specific purpose, and then variously designate a resource for each region by using a separately defined resource.

According to the disclosed subject matter, it is possible to avoid or mitigate inter-cell interference more efficiently while using partial frequency reuse technology.

Hereinafter, specific examples for carrying out the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below are intended to illustrate the present invention by way of example and the scope of the present invention is not limited to the specific embodiments.

1 illustrates a communication framework according to an embodiment of the present invention.

Referring to FIG. 1, the communication framework according to the present embodiment may include a plurality of NodeBs and a Central Node. The Central Node manages multiple NodeBs, and each NodeB forms a cell so that the UE can wirelessly connect to the NodeB.

In FIG. 1, resource management on a communication framework may be performed at each NodeB or may be performed at a Central Node.

For example, in case of LTE, since there is no central node, it is possible to manage resources in a distributed manner through an inter-interface between NodeBs. In the case of IMT-Advanced, it is possible to intensively manage resources through the Central Node.

In FIG. 1, a radio interface (RI) represents an interface between a terminal and a NodeB, and an X2 interface represents an interface between the NodeBs. The X3 interface represents an interface between the Central Node and NodeB.

According to an embodiment of the present invention, the Central Node, NodeB, and the terminal may exchange messages for inter-cell interference control through the RI, X2, and X3, and may be proactive or reactive based on the related message. (reactive) it is possible to perform inter-cell interference coordination and avoidance.

According to an embodiment of the present invention, four message types for interference control may be used.

The Type 1 message is configured as (SBi, EBi) or (Sector_i_ID, SBi, EBi) when ICIC_FBS characteristics of the corresponding cells are specified in advance.

The Type 2 message is configured as (Ui, SBi, EBi) or (Ui, Sector_i_ID, SBi, EBi) when ICIC_FBS characteristics of the corresponding cells are not specified in advance.

The Type 3 message is {(U1, SB1, EB1), (U2, SB2, EB2)} or {(U1, Sector_1_ID, SB1, EB1), (U2, Sector_2_ID, when the ICIC_FBS characteristics of the cells may be different. SB2, EB2)}.

Type 4 messages are: {U, (SB1, EB1), (SB2, EB2)} or {U, (Sector_1_ID, SB1, EB1), (Sector_2_ID, SB2, EB2)} It is composed.

Dual Type 1 and Type 2 messages can be delivered through the X2 interface, and Type 3 and Type 4 messages can be delivered via the X3 interface.

The NodeB receiving the message allocates and manages resources using the received message. ICIC_FBS is determined according to the interference control algorithm to be operated, and parameters of related messages may be operated regularly or irregularly, fixedly or variably depending on whether the interference control is semi-static or dynamic. have.

Here, "{B (i)} or ICIC_FBS" means information on resources to be used by the cell. This is a logical concept. As described above, the ICIC_FBS definition element may be represented by B (i), (SBi, EBi), Ui, and Sector_i_ID.

"B (i)" means a specific resource designated as a forbidden band for the i-th cell. B (i) is used for a specific purpose in the i-th cell and can be changed semi-static regularly and irregularly. B (i) can broadcast to terminals in the cell. When only one cell exists in one node, only one B (i) exists. In this case, B (i) of the serving cell may or may not intersect with B (j) of the neighboring cell. This B (i) can be initially assigned or changed during operation according to the policy of the Central Node or OAM server. In addition, it is possible for an individual node to initially designate B (i) or change it during operation based on information obtained through communication with surrounding nodes. This B (i) is a logical concept. For example, if a physical resource block (PRB) from 0 to 11 is allocated to cell 1, B (1) may be designated as a 0 through 5 PRB. At this time, the designated B (1), that is, PRBs 0 to 5 may be used for a specific purpose according to the policy. For convenience of description, B (i) is named as a prohibited band, but it cannot be interpreted as being limited to mean a prohibited area.

"(SBi, EBi)" means a start position and an end position of a frequency corresponding to B (i). When the PRB consists of consecutive subcarriers (Centralized PRB Allocation), it is possible to express SBi and EBi in the direct frequency band. In addition, indirect expressions in the form of dividing the entire B (i) by the size and allocating PRBs in ascending or descending order and logically defining SBi and EBi based on the order values are also possible. However, when discontinuous subcarriers are assembled to form a PRB (Distributed PRB Allocation), it is impossible to express SBi and EBi in the form of a direct frequency.

"U (i)" means an attribute of B (i). For example, it is possible to use B (i) as a preferred band or as a non-preferred band depending on the value of U (i).

"Sector_i_ID" means an ID such as a node / sector / cell corresponding to B (i).

2 illustrates a frequency reuse characteristic and a cell planning method according to an embodiment of the present invention.

In Figure 2, 2-1 represents the frequency assigned to the operator. The operator is allocated a frequency such as 2-1 for a mobile communication service providing any wireless method. The allocated frequency band can be divided into several frequency assignments (FAs) according to the method supported by the wireless transmission method.

In FIG. 2, 2-2-1 divides the allocated frequency band into three types, FA1, FA2, and FA3. If there is interference between cells, cell planning is performed by setting the frequency reuse index to 3 as shown in 2-2-2. It is possible.

In addition, in order to increase the total data throughput of a cell in one base station, it is also possible to perform sectoring as shown in 2-3-1 using a directional antenna. 2-3-1 shows three sectors for each FA using a directional antenna for one base station. In this case, cell planning such as 2-3-2 is possible.

 In Figure 2, 2-4-1 is a feature of the radio transmission scheme shows that only FA1 can be used if there is no interference. In this case, cell planning may be performed by setting the frequency reuse index to 1 as shown in 2-4-1.

In addition, even if there is no inter-cell interference, if the operator is assigned frequencies of FA2 and FA3, cell planning may be performed as in 2-5-2. In this case, when the same wireless method is used, when the terminal connected to the radio moves from the FA1 cell to the FA1 cell, it is defined as an intra-frequency handover, and when the terminal moves to another FA such as moving from FA1 to FA2 It can be defined as inter-frequency handover.

The frequency reuse index may be set to 1 if the radio access method does not receive intercell interference. However, if there is an inherent inter-cell interference due to the radio transmission method, divide the frequency allocated to the operator and set the frequency reuse index to 2 or more to perform cell planning or the frequency reuse index to 1 but add a special interference mitigation method to perform cell planning. It is possible.

3 illustrates a frequency reuse characteristic and a cell planning method according to another embodiment of the present invention. This is based on the carrier aggregation scheme. When the available frequency carriers are C1, C2, and C3 in order to improve the total data processing performance of the cell, they may be used simultaneously in one base station.

In FIG. 3, C1, C2, C3 may be allocated continuously, such as 3-1, or may be allocated discontinuously, such as 3-2. In addition, one operator may be allotted C1, C2, C3 or C1, C2, C3 may be assigned to different operators.

In FIG. 3, when there is no interference, it is possible to perform cell planning of each of C1, C2, and C3 as in 3-2-2. For example, it is possible to utilize all of C1, C2, C3 according to the capability of the terminal. In addition, the total data throughput of the cell may be increased through sectoring, such as 3-3-2, through the directional antenna.

4 illustrates a resource according to an embodiment of the present invention.

In FIG. 4, 400 represents a resource allocated to a business operator. The frequency axis of the resource allocated to the operator is composed of frequency bands allocated, and the time axis may be composed of a frame, a subframe, a PRB unit (Physical Resource Block unit) on the time axis, a symbol, and the like.

For example, one frame may consist of several subframes, one subframe may consist of several PRB units, and one PRB unit may consist of several symbols. In addition, the PRB unit on the frequency can be configured by gathering several subcarriers on the frequency axis.

 In FIG. 4, when successive subcarriers such as 400 form one PRB unit in the frequency axis, this may be referred to as a centralized PRB. Alternatively, a PRB may be constructed by looking at some discrete subcarrier units, which may be referred to as a distributed PRB. When using a distributed PRB, it is possible to reduce the frequency selective fading in a stochastic manner compared to using a Cetnrallized PRB.

According to an embodiment of the present invention, "resource" may be a PRB composed of PRB (Physical Resource Block) units on a frequency and time axis, a set of such PRBs, or a corresponding frequency band.

5 illustrates a configuration of an intercell interference adjusting apparatus according to an embodiment of the present invention.

In FIG. 5, an inter-cell interference coordination apparatus 500 may be provided in a base station node managing a cell in a mobile communication system. The inter-cell interference control apparatus 500 may include an acquirer 501, a determiner 502, and an adjuster 503.

The acquirer 501 acquires information on resources to be used by the serving cell and neighbor cells. For example, the acquirer 101 may be an interface module provided in the base station node, and the obtained information may be ICIC_FBS, which is information about a resource.

Resource information can be generated by the base station node by exchanging Type 1 or Type 2 messages with other base station nodes in the vicinity, or by receiving Type 3 or Type 4 messages from an Operation Administration and Maintenance (OAM) server or a Central Node. It is possible to obtain by.

The determination unit 102 may be a resource management module of the L3 layer provided in the base station node.

In addition, the determination unit 102 divides the serving cell into a plurality of areas, and designates resources by area. For example, the serving cell may be divided into a central region and a peripheral region, and the peripheral region may be divided into an adjacent region, which is an area adjacent to another cell, and a non-adjacent area, which is an area not adjacent to another cell. In this case, the determination unit 102 may designate a resource for each region. The designated resource means a resource to be allocated to the terminal when the terminal is located in the corresponding area. For example, it is possible to designate a whole resource (Ω, for example, PRB # 0 to # 11) in the central region, and specify a resource except for a resource separately defined for interference control in the entire region. For example, a resource such as [Ω-B (1)] can be designated in the peripheral region. In this case, the resource specified in the peripheral area may always be a resource specified and optionally specified resources. Details will be described later.

In addition, the determination unit 102 provides an interference characteristic for each resource. When interference control is performed through resource scheduling or resource management, such interference characteristics may be used as basic information for interference control. According to one embodiment of the present invention, four kinds of interference characteristics may be used.

The first interference characteristic IFZ may be given to a resource for which no interference occurs. The second interference characteristic LIZ may be given to a resource that may generate interference but may avoid interference by power adjustment. Although the third interference characteristic (ICZ) may cause interference, it may be given to a resource capable of avoiding interference by physical interference cancellation with the terminal. The fourth interference characteristic (HIZ) may be given to a resource that may cause interference, but may avoid interference through message exchange with another cell. Interference avoidance through the exchange of messages with other cells means that, for example, if you want to use a particular resource exclusively, the relevant information is contained in an X2 message and other cells around you are informed of this fact and given the exclusive right to avoid interference. Can be.

The adjusting unit 103 may be a resource management module of the L2 layer or the L1 layer provided in the base station node.

In addition, the controller 103 performs allocation scheduling or power management for resources according to the position of the terminal in the serving cell. For example, the controller 103 may allocate a resource designated by the determiner 102 according to the location of the terminal and perform power management on the allocated resource. In this case, it is possible to adjust which resources are allocated in what order (scheduling view) or at which power level the allocated resources are managed (power management view) in consideration of the interference characteristics given to each resource. For example, it is possible to preferentially allocate a resource having a first interference characteristic (IFZ) to other resources or to manage using a maximum power value.

6 illustrates an interference control device and a communication framework according to an embodiment of the present invention. In FIG. 6, each node receives ICIC_FBS from the Central Node, and each cell is assumed to be one cell without sectoring.

Referring to FIG. 6, the Central Node drops ICIC_FBS to each Node through a Type4 message. For example, Node 1 may receive information such as {(U1, SB1, EB1), (U2, SB2, EB2), ...}. For example, if Node 1 receives this message, it can be seen that the resources from SB1 to EB1 among the resources allocated to it are designated for a specific purpose, and the characteristics (eg, whether they are preferred bands or non-preferred bands) through U1. You can also see. The resource characteristic information of the neighboring Node 2 can also be known.

D.RRM (Distributed Radio Resource Manegement) in the L3 layer of Node 1 classifies its own cell by area using B, U, SB, EB, etc. for its own cell and neighboring cell, and resource in each area. Specify. The interference characteristics (IFZ, LIZ, ICZ, HIZ, etc.) for each resource are determined.

D.RRM delivers resources specified by region and interference characteristic information assigned by resources to L2 layer through CSAPL2 interface and to L1 layer through CSAPL1 interface.

In this state, the D.RRM determines whether the location of the currently connected terminal and the location of the corresponding terminal belong to the terminal through the measurement report of the terminal RRC. Information about the location of the terminal and the corresponding area is transmitted to the L2 layer through the CSAPL2 interface. The L2 layer allocates resources assigned to the corresponding area to the terminal. At this time, it is possible to determine the allocation order in consideration of the interference characteristics applied to each terminal. In addition, information about the location of the terminal and the corresponding area is transmitted to the L1 layer through the CSAPL1 interface. The L1 layer places a constraint on the downlink power. In addition, the L1 layer provides the corresponding information to the terminal through the RRC to limit the uplink power based on this information. At this time, it is possible to restrict in consideration of the interference characteristics applied to the resource.

Algorithm-specific allocated resources and resource-specific interference characteristics may be different. By using this, the central node can manage and coordinate such interference information centrally through the X3 interface, or can coordinate each other in a distributed form by exchanging such interference information through the X2 interface between nodes without the central node. have. Such interference information is held by L3 of a node. If the interference information is provided to the L2 of the node through the CSAPL2 interface, the interference information can be avoided or scheduled by providing resource information or interference cancellation information of the terminal where interference is expected or already occurred, and measurement (through the CSAPL1L2 interface) For example, CQI) may also be used for scheduling considering such interference.

In addition, the L3 may provide such interference information through the CSAPL1 interface to proactively or reactively intervene in power control of the current Node L1. In this case, UL (uplink) interference may be reported to Node L3 through the CSAPL1 interface measured at Node L1, and DL (downlink) interference may be reported to UE L3 measured at UE L1 and transmitted to Node RRC as an RRC message. Can be reported.

In X2, a message called Load Indication may be defined, and the Ux, SBx, EBx, and Sector_i_IDs of the opposite nodes of the Distributed RRM may be identified by exchanging Type 1 or Type 2 messages. Inter-cell interference coordination can be performed through the Load Information (LI) message, and data for the modified inter-cell interference coordination can be collected through ResourceStatusUpdate (RSU) for each terminal. The update relationship setting may be performed in a manner that a node to collect sends a Resource Status Request (RSReq) to a neighbor node and responds through a Resource Status Response (RSRsp).

All of this information can be managed by distributed RRM, which is an individual node, for coordination and avoidance between cells. In addition, when using the X3 interface, the Central Node may provide Ux, SBx, EBx, and Sector_i_ID for each node through Type 3 or Type 4 in terms of cell planning, whereas the Central Node collects and manages the information. can do.

In addition, like the X2 interface, data can be collected for coordination between cells in each node through the RSUPlus procedure. Such a relationship can be established through the RSUPlus between the central node and the corresponding node through RSReqPlus and RSRspPlus. The RSUPlus reports to the Central Node by using the RSUPlus whenever the resource information including the interference of the node having such a relationship is updated.

In the LI, UL Interference Overload Indication (OI) information for each PRB is inserted into each sector managed by the Node (that is, a cell ID including the sector concept), and the sector managed by the target NodeB that wants to adjust the sector managed by the NodeB. It provides UL High Interference Indication (HII) for each PRB corresponding to (i.e., cell ID including sector concept), and provides average DL Maximum Tx Power per PRB for each sector of a node generating LI. The other node receiving the LI considers the OI (high, medium, low) for each PRB measured for each sector of the node providing the LI, and is provided for each sector of the node receiving the LI that affects the sector of the node providing the LI. In consideration of HII (high, low), it is possible to mitigate interference through UL Power Control or to avoid interference through UL scheduling. In addition, it is possible to mitigate interference through DL Power Control in consideration of DL Maximum Tx Power for each sector of a Node providing LI.

7 illustrates a location of a terminal according to an embodiment of the present invention.

Referring to FIG. 7, the case of U1 is a case where the terminal is inside the cell 1 and the case where U1-3, U1-2, U1-23 is the terminal is at the cell boundary. For example, U1-3 is the case where the terminal is adjacent to cell 3 while at the cell boundary, U1-2 is the case where the terminal is adjacent to cell 2 while at the cell boundary, and U1-23 is the case where the terminal is at the cell boundary and is in cell 2 and cell 3 It can be adjacent.

Inter-cell interference control according to an embodiment of the present invention is performed under the premise that the region where the terminal is located can be identified as shown in FIG. 7. In this case, the location of the terminal may be determined using location information such as GPS, TOA (Time Of Arrival), TDOA (Time Difference Of Arrival), and RSRP (Received Signal Received Power).

According to an embodiment of the present invention, a terminal located in an inner cell is managed with a power suitable for communication within the limit of not interfering with other cells, and by using all frequency bands of the cell, maximum performance can be achieved. I think you can. Since the UE located at the cell boundary does not improve the performance by allocating an available frequency band, priority may be given to ensuring high SINR.

8 illustrates resource information according to an embodiment of the present invention.

Referring to FIG. 8, it can be seen that resource information is configured in units of PRBs. In FIG. 8, if B (i) is defined as a resource designated for a specific purpose, the total band? For cells 1, 2, and 3 is 0 to 11, and B (1) is 0, 1, 2, 3, 4, B (2) is 4,5,6,7,8,9 and B (3) is 0,1,8,9,10,11.

Next, a method of adjusting interference between cells according to various embodiments of the present disclosure will be described.

Example 1-1

By defining B (i), a resource that is reluctant to be allocated to the cell periphery region (CEU) of the serving cell i (Cell_i), the frequency in B (i) is not used for the CEU of Cell_i. In the case of the cell center region (ICU), the entire band can be used under the premise that it is managed at an appropriate power and does not cause interference to the CEU or ICU of the adjacent cell j.

If there is an interfering cell (Cell_j) that is an adjacent neighboring cell causing interference, a portion of resource B (j) that is reluctant to be allocated to the CEU of Cell_j is made available in the CEU of Cell i.

For example, in the case of U1-2, CEU in cell 1 and located adjacent to cell 2, a portion of the band of the frequency of B (2) of cell 2 (that is, the area B (1) in the entire band Ω of cell 1). Band and the common area of the B (2) area).

If expressed in detail as follows.

UB1, ICU = Ω-(1)

UB1, CEU = Ω-B (1) --- Equation (2)

UB1-2, CEU = UB1, CEU ∩ B (2) --- Equation (3)

UB1-3, CEU = UB1, CEU ∩ B (3) --- Equation (4)

UB1-23, CEU = UB1, CEU ∩ B (2) ∩ B (3) --- Equation (5)

Considering the notation according to the position of the terminal of FIG. 7, as shown in FIGS. 8 and 9, if frequency bands B (1), B (2), and B (3) that are reluctant to be allocated are defined, Equation 1 indicates that a band available to a terminal located inside cell 1 (ie, UE1, ICU) becomes all frequency bands allocated in the cell, that is, Ω, and a terminal located at a cell boundary (ie, UE1, CEU) is available. The band is the band obtained by subtracting B (1) from Ω as shown in equation (2).

In detail, the UB1 and CEUs are classified according to regions, and the UEs UE1-2 and CEU located near the cell 2 at the boundary of the cell 1 may use the available bands of the UB1 and CEU and the B ( The intersection of 2) can be used. Terminals UE1-3 and CEU located close to cell 3 at the boundary of cell 1 may use an intersection of available bands of UB1 and CEU and B (3) as shown in Equation (4). Terminals (UE 1-23, CEU) located close to cell 2 and cell 3 at the boundary of cell 1 are connected to the available band of UB1, CEU and the intersection of B (2) and B (3), as shown in equation (5). Can be used.

Referring to FIG. 9 again, the available bands for UE1, ICU, UE1, CEU, UE1-2, CEU, UE1-3, CEU, UE1-23, and CEU UEs located in Cell 1 as shown in FIG. UB1, ICU in formula (1), UB1, CEU in formula (2), UB1-2, CEU in formula (3), UB1-3, CEU in formula (4), and UB1- in formula (5), respectively. 23, can be the CEU.

Referring to this from the perspective of PRB as shown in FIG. 8, B (1), B (2), and B (3) are 0, 1, 2, 3, 4, 5, and 4 for Cell 1, Cell 2, and Cell 3, respectively. 5,6,7,8,9 and 8,9,10,0,1. At this time, by applying the notation according to the terminal location as shown in Figure 7 UE1, ICU, UE1-23, CEU, UE1-2, CEU, UE1-3, CEU, UE2-13, CEU, UE3-12, CEU, UE2 -1, CEU, UE3-1, CEU, UE2-3, CEU, UE3-2, CEU, UE2, ICU, UE3, ICU respectively shows the parts available in the PRB as shown in FIG.

In FIG. 10, UE1 and ICU, which are the center regions of Cell 1, may use 0 to 11 which are the entire band of FIG. 8. Of these, 0, 1, 2, 3, 4, and 5 are the B (1) areas, so that the UEs in the CEUs of neighboring cells can be used, so appropriate power must be used. , 7, 8, 9, 10, and 11 are areas common to B (2) of cell 2, which is the adjacent cell, and not common to B (3) of cell 3, and 10, 11 are bands available for cell 1. In 6, 7, 8, 9, 10, and 11, it is an area which is common to B (3) of cell 3 which is an adjacent cell and is not common to B (2) of adjacent cell 2. Thus, 6, 7, 10, and 11 are relatively free of interference. 8 and 9 are areas common to B (2) of cell 2 and B (3) of cell 3 in 6, 7, 8, 9, 10, and 11, which are available bands in cell 1, and are both in cell 2 and cell 3 Since the band is not used, the possibility of interference is very low.

In FIG. 10, 8 and 9 may be used in the cell 1 region UE1-23, CEU where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other. That is, UE2-3, CEU, UE2-13, CEU, UE2-3, CEU and CEUs of cell 3 (that is, UE3-1, CEU, UE3-12, CEU, UE3-2, CEU) are not used. Band. Therefore, it is very unlikely to interfere with the CEU of cell 2 or cell 3.

In FIG. 10, in the case where UE1-2 and CEU which are the cell 1 regions in the overlapping circles of the dotted lines of the cell 1 and the cell 2 except for the overlapping portions of the three dotted circles of the cell 1, the cell 2, and the cell 3, 6, 7 (i.e., parts not overlapping B (3) in 6, 7, 8, 9, 6, 7, 8, 9, 10, 11 available in cell 1) and 8, 9 (I.e., a part not overlapping with B (2) at 8, 9, 10, 11, which is a part overlapping with B (3) at 6, 7, 8, 9, 10, 11 available in cell 1). At this time, since 8 and 9 belong to B (2) and B (3), the possibility of interference is lower than that of 6 and 7.

In FIG. 10, in the case where UE1-3 and CEU which are the cell 1 regions in the overlapped circles of the cells 1 and 3 except for the overlapped portions of the three dotted circles of the cells 1, 2 and 3, 10, 11 (i.e., the overlapping part of B (3) in 6, 7, 8, 9, 10, 11 available in cell 1, the part not overlapping B (2) in 8, 9, 10, 11) and 8, 9 (I.e., a part overlapping with B (2) at 8, 9, 10, 11, which is a part overlapping with B (3) at 6, 7, 8, 9, 10, 11 available in cell 1). At this time, since 8 and 9 belong to B (2) and B (3), the possibility of interference is lower than that of 10 and 11.

In FIG. 10, in the case where UE2-13, CEU, which is the cell 2 region, in which the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other, the remaining bands of B2 minus B (2) and B (1) and 0 and 1 which are common parts of B (3) can be used. Here, since 0 and 1 are resources not used in the CEUs of the cell 1 and the cell 3, the possibility of interference is very low.

In FIG. 10, in the case where UE3-12, CEU, which is the cell 3 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other, in the Ω 3 subtracting B (3) and B (1) and 4 and 5 which are common parts of B (2) can be used. Here, since 4 and 5 are resources not used in the CEUs of Cell 1 and Cell 2, the possibility of interference is very low.

In FIG. 10, in the case where the dotted circles of Cell 1 and Cell 2 overlap each other except for the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 0, 1 when the cell 2 region is UE2-1, CEU. , 2, 3 (ie, common bands of 0, 1, 2, 3, 10, 11 and B (1) available) can be used. Here, 0, 1, 2, and 3 have a relatively low possibility of interference in relation to the CEU of the cell 1.

In FIG. 10, in the case where UE3-1 and CEU, which are the cell 3 regions, are overlapped with the dotted circles of the cell 1 and the cell 3 except for the overlapped portions of the three dotted circles of the cell 1, the cell 2, and the cell 3, 2 and 3 , 4, 5 (ie, common bands of 2, 3, 4, 5, 6, 7 and B (1) available) can be used. Here, 2, 3, 4, and 5 have a relatively low possibility of interference in relation to the CEU of the cell 1.

In FIG. 10, 0 and 1 are cell 2 regions UE2-3 and CEU at portions where the dashed circles of cell 2 and cell 3 overlap except for portions where the three dashed circles of cell 1, cell 2 and cell 3 overlap. , 10, 11 (i.e., a part belonging to B (3) in 0, 1, 2, 3, 10, 11 available in the CEU of cell 2) may be used. From the point of view of cell 1, 0 and 1 are bands that are not used in the CEU, so the probability of interference is relatively low. 10 and 11 are bands used in the CEU, but the UE2-3, CEU and UE1-3, CEU are virtually non-adjacent. It does not appear to interfere with the CEU of 1.

In FIG. 10, 4 and 5 for UE3-2 and CEU, which are the cell 3 regions, in which the dotted circles of Cell 2 and Cell 3 overlap except for the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap. , 6, 7 (i.e., the part belonging to B (2) in 2, 3, 4, 5, 6, 7 available in the CEU of cell 3), 4, 5 is the CEU of cell 1 Since it is an unused region in, it can be seen that it does not interfere with the CEU of cell 1. In addition, from the cell 1 perspective, 6 and 7 are used in the CEU of the cell 1, but since UE3-2, CEU, UE1-2, and CEU are virtually not adjacent to each other, they do not directly interfere with the CEU of the cell 1.

In FIG. 10, since the ICUs (UE2, ICU) of the cell 2 and the ICUs (UE3, ICU) of the cell 3 are managed with appropriate powers, the ICU (UE1, ICU) of the cell 1 or the CEU (cell 1) of the cell 1 from the cell 1 perspective. UE 1, CEU) does not cause interference, and UE2, ICU, UE3, ICU can use the entire band like UE 1, ICU.

Example 1-2

Example 1-2 defines a common use band AB having a frequency reuse index of 1 in all cells, and defines a prohibited band B (i) of each cell based on the remaining bands except AB in all bands Ω.

For example, the ICU, the central region of the cell, uses the full band Ω. The periphery of the cell basically uses the entire band Ω minus the common use band AB and the forbidden band B (i). And the peripheral region of the cell selectively uses the common use band AB according to the given condition. In this case, even if the AB is used, interference may be avoided through interference cancellation with the UE, or a case in which an exclusive use of the AB may be guaranteed by exchanging a message with another cell.

Referring to the PRB view of FIG. 13, 0, 1, and 2 are defined as the common use band AB in cells 1, 2, and 3. And B (1) is 3, 4, 5, 6, 7 and B (2) is 6, 7, 8, 9, 10 and B (3) is defined as 3, 4, 9, 10, 11.

That is, as shown in FIG. 11, B (1), B (2), and B (3) are designated in the frequency band excluding AB in the entire band Ω. At this time, the band available to the UE1, ICU is the entire band Ω, and does not cause interference to neighbor cells through proper power management in the entire band use. UE1, CEU available bands are always available bands and optionally available bands. The always available band is the remainder except for B (1), and the optionally available band is the AB portion.

At this time, the AB may be used, but since the AB may also use the CEU of another neighboring cell, if the UE at the boundary of another neighboring cell uses the AB and the AB is used at the boundary of the serving cell, it interferes with UB1 and CEU. Since this can come in, a countermeasure is required in using AB.

The first countermeasure is to signal to the other cell that the serving cell is using the AB when trying to use the AB. For example, when the UE1-2, the UE of the CEU intends to use the AB, it is possible to inform the cell 2 and the cell 3 of this information and guarantee the exclusive use. The second countermeasure may be used if interference cancellation can be always operated.

In FIG. 11, the bands available to UE1-2 and CEU, which are areas adjacent to Cell 2 in the area of Cell 1, are UB1-2 and CEU (that is, [Ω-AB-B (1)] and B which are always available). The intersection of (2), and optionally available AB.

In FIG. 11, the bands available to UE1-3 and CEU, which are adjacent to Cell 3 in the area of Cell 1, are UB1-3 and CEU (that is, [Ω-AB-B (1)] and B which are always available). Intersection of (3), and optionally available AB.

In FIG. 11, the bands available to UE1-23 and CEUs, which are adjacent to Cells 2 and 3 in the region of Cell 1, are UB1-23, CEU (always available [Ω-AB-B (1)]). The intersection of B (2) and B (3), and optionally available AB.

There may be 0 ~ 2 interferences in the use of AB. In this case, the first measure is to freely use the AB if it is possible to cancel the interference, and the second measure is exclusively in one cell using the X2 interface. If you decide to use it, you can prohibit the use of AB in other cells that receive this information.

The above-described contents are expressed as follows.

AB = frequency reuse 1 area --- Equation (6)

UB1, ICU = Ω --- Equation (7)

UB1, CEU = Ω-AB-B (1) --- Equation (8)

UB1-2, CEU = UB1, CEU ∩ B (2) --- Equation (9)

UB1-3, CEU = UB1, CEU ∩ B (3) --- Equation (10)

UB1-23, CEU = UB1, CEU ∩ B (2) ∩ B (3) --- Equation (11)

For example, a resource band that can be used by the center region of cell 1 is shown in Equation (7). In addition, the resource band that can be used by the peripheral region of the cell 1 is basically guaranteed as in Equation (8), and optionally to use Equation (6).

Looking at the resource band that can be used by the surrounding area of the cell 1 by specific area, UE1-2, CEU can always use the intersection of UB1, CEU and B (2) as shown in Equation (9), AB can optionally be used. Similarly, UE1-3 and CEU can always use the intersection of UB1, CEU and B (3) as shown in Equation (10), and can optionally use AB depending on conditions. And UE1-23, CEU can always use the intersection of UB1, CEU and B (2) and B (3), as shown in equation (11), and can optionally use AB according to the conditions.

Referring back to FIG. 11, the available band UB for UE1, ICU, UE1, CEU, UE1-2, CEU, UE1-3, CEU, UE1-23, CEU is UB1, ICU of Equation (7), respectively. , UB1, CEU of formula (8), UB1-2, CEU of formula (9), UB1-3, CEU of formula (10), UB1-23, CEU of formula (11) and at the same time The common use band AB may optionally be used.

At this time, UE1, ICU, UE1-23, CEU, UE1-2, CEU, UE1-3, CEU, UE2-13, CEU, UE3-12, CEU, UE2-1, CEU, UE3-1, FIG. 12 shows a portion in which CEU, UE2-3, CEU, UE3-2, CEU, UE2, ICU, UE3, and ICU can be used as a PRB, and a PRB allocated to each position from a cell 1 perspective.

In FIG. 12, UE1, ICU, which is the center region of Cell 1, may use 0 to 11, which is the entire band. In this case, 0, 1, and 2 may be used when exclusive use signaling or interference cancellation is possible in the AB band. 3, 4, 5, 6, and 7 are the B (1) areas and can be used by the CEUs of neighboring cells. 9 and 10 are bands that are not used by both the CEUs of the cell 2 and the cell 3 so that no interference occurs. 8 and 11 belong to B (2) and B (3), respectively, and thus are relatively free of interference.

In FIG. 12, 0, 1, and 2 are defined as being available because the frequency reuse index is 1, and may be used in a corresponding cell when interference cancellation is possible or when exclusive use is guaranteed through signaling.

In FIG. 12, in a case where UE 1 -23 and CEU, which are cell 1 regions, overlap with each of the three dotted circles of cell 1, cell 2, and cell 3, 0, 1, 2 may be used or not available depending on conditions. Since 9 and 10 belong to B (2) and B (3) in the remaining bands 8, 9, 10 and 11 except for AB and B (1) in the entire bands 0 to 11, they can always be used. In this case, since 9 and 10 are not used by the CEUs of neighboring cells, they may be bands that do not cause interference.

In FIG. 12, 0, for UE1-2 and CEU, which are the cell 1 regions, at the overlapping circles of the dotted lines of the cell 1 and the cell 2 except for the overlapping portions of the three dotted circles of the cell 1, the cell 2, and the cell 3, 0, 1,2 may or may not be available depending on conditions. 8, 9, and 10 may be always used since they belong to B (2) in the remaining bands 8, 9, 10, and 11 except for AB and B (1) in the entire bands 0-11. At this time, since 9 and 10 also belong to B (3), the band can be free from interference.

In FIG. 12, 0, for UE1-3 and CEU, which are the cell 1 regions, in the overlapping circle of the dotted lines of cell 1 and cell 3 except for the overlapping portion of the three dotted circles of cell 1, cell 2, and cell 3, 0, 1,2 may or may not be available depending on conditions. 9, 10, and 11 are parts belonging to B (3) in the remaining bands 8, 9, 10, and 11 except for AB and B (1) in the entire bands 0 to 11, and thus can always be used. At this time, since 9 and 10 also belong to B (2), the band can be free from interference.

In FIG. 12, in the case where UE2-13, CEU, which is the cell 2 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other, 0, 1, 2 may or may not be available depending on conditions. Can be. Since 3 and 4 belong to B (1) and B (3) in the remaining bands 3, 4, 5, and 11 except for AB and B (2) in the entire bands 0 to 11, they can always be used. In this case, since 3 and 4 are not used by the CEU of the adjacent cell, 3 and 4 may be bands that do not cause interference.

In FIG. 12, in the case where UE3-12, CEU, which is the cell 3 region, in which portions of three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 0,1,2 may or may not be available depending on conditions. Can be. Since 6 and 7 belong to B (1) and B (2) in the remaining bands 5, 6, 7, and 8 except for AB and B (3) in the entire bands 0 to 11, they can always be used. In this case, since 6 and 7 are not used by the CEUs of neighboring cells, they may be bands that do not cause interference.

In FIG. 12, 0,1 for UE2-1, CEU, which is a cell 2 region in a portion where the dotted circles of Cell 1 and Cell 2 overlap except for the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other. 2 may or may not be available depending on conditions. Since 3, 4, and 5 belong to B (1) in the remaining bands 3, 4, 5, and 11 except for AB and B (2) in the entire bands 0 to 11, they can always be used. Of these, since 3 and 4 do not use the CEU of cell 3, they can be seen as completely free from interference.

In FIG. 12, in the case where UE3-1, CEU, which is a cell 3 region, overlaps the dotted circles of Cell 1 and Cell 3 except for the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 0,1 2 may or may not be available depending on conditions. 5, 6, and 7 are parts belonging to B (1) in the remaining bands 5, 6, 7, and 8 except for AB and B (3) in the entire bands 0 to 11, and thus may be always used. Of these, since 6 and 7 do not use the CEU of cell 2, they can be seen as completely free from interference.

In FIG. 12, 0,1 for UE2-3, CEU, which is a cell 2 region in a portion where the dotted circles of cell 2 and cell 3 overlap except for the portions where the three dotted circles of cell 1, cell 2, and cell 3 overlap each other. 2 may or may not be available depending on conditions. Since 3, 4, and 11 belong to B (3) in the remaining bands 3, 4, 5, and 11 except for AB and B (2) in the entire bands 0 to 11, they can always be used. Of these, 3 and 4 do not use the CEU of cell 1, so they can be seen as completely free of interference.

In FIG. 12, 0,1 for UE3-2 and CEU, which are cell 3 regions, where the dotted circles of cell 2 and cell 3 overlap except for the portions where the three dotted circles of cell 1, cell 2, and cell 3 overlap. 2 may or may not be available depending on conditions. 6, 7, 8 may be always used because they belong to B (2) in the remaining bands 5, 6, 7, and 8 except for AB and B (3) in the entire bands 0-11. Of these, since 6 and 7 do not use the CEU of cell 1, they can be seen as completely free from interference.

In FIG. 12, since the ICUs (UE2, ICU) of the cell 2 and the ICUs (UE3, ICU) of the cell 3 are managed with appropriate powers, the ICU (UE1, ICU) of the cell 1 or the CEU (cell 1) of the cell 1 from the cell 1 perspective. It can be seen that it does not cause interference to UE 1, CEU), and like the UE1, ICU, the entire band Ω may be used.

Example 1-3

In Embodiments 1-3, basically, B (i), which is a resource that is reluctant to be allocated to the peripheral area CEU of the serving cell i (Cell_i), is defined like in Embodiment 1-1. In addition, a band corresponding to B (i) is not used for the CEU of Cell_i, and an additional portion of B (i) is selectively used according to a condition. In addition, the entire band is used for the central region (ICU) of Cell_i under the premise that interference is not caused to the CEU of the neighboring cell j or the ICU of the neighboring cell j through power management.

For example, UE1-2 and CEU in cell 1 and located adjacent to cell 2 basically use the remaining band after subtracting the B (1) band from the total band Ω, and optionally using some band of B (1). do. Some bands of B (1) may be used in situations in which interference cancellation is possible or in situations in which monopoly rights may be granted through inter-cell signaling.

Expressed in the formula, Examples 1-3 can be expressed by using the following equation in addition to the formula (1), (2), (3), (4), (5).

C1B1-2, CEU = B (1) ∩ B (2) --- Equation (12)

C1B1-3, CEU = B2 (1) ∩ B (3) --- Equation (13)

C1B1-23, CEU = B (1) ∩ [B (2) ∪ B (3)]

            = CB1-2, CEU ∪ CB1-3, CEU --- Eq. (14)

Equations (12), (13) and (14) represent resources selectively available in the CEU of cell 1.

According to embodiments 1-3, resources available for each region are shown in FIG. 14.

Referring to FIG. 14, the center areas UE1 and ICU of cell 1 may use resources corresponding to UB1 and ICU. UB1, ICU may be the total resource? Assigned to the cell. The peripheral areas UE1 and CEU of the cell 1 may basically use resources corresponding to UB1 and CEU. UB1 and CEU may be resources corresponding to the remaining bands except for B (1) in the total resource Ω. In addition, the peripheral areas UE1 and CEU of Cell 1 may selectively use resources corresponding to C1B.

For example, the region (UE1-2, CEU) adjacent to cell 2 at the boundary of cell 1 can always use the band corresponding to the intersection of UB1, CEU and B (2), and C1B1-2, CEU, As in (12), a band corresponding to the intersection of B (1) and B (2) can be selectively used.

Similarly, the region close to cell 3 (UE1-3, CEU) at the boundary of cell 1 can always use the band corresponding to the intersection of UB1, CEU and B (3), and C1B1-3, CEU, that is, Equation (13) As described above, a band corresponding to the intersection of B (1) and B (3) can be selectively used.

The regions UE1-23.CEU adjacent to the cell 2 and the cell 3 at the boundary of the cell 1 can always use the band corresponding to the intersection of UB1, CEU and B (2) and B (3), and C1B1- The band corresponding to the union of B (2) and B (3) and the intersection of B (1) can be selectively used as shown in 23, CEU, that is, Equation (14).

At this time, if all cells intend to use the C1B region, there may be 0 to 2 interference regions, and there may be two countermeasures.

The first countermeasure is to freely use C1B in situations where interference cancellation is possible, and the second countermeasure is to inform other cells of exclusive use in one cell using the X2 interface and prohibit the use of C1B in other cells that receive this information. There is a way to.

Looking at the embodiment 1-3 from the PRB perspective as shown in FIG.

In FIG. 8, B (1) of cell 1 is 0, 1, 2, 3, 4, 5, B (2) of cell 2 is 4, 5, 6, 7, 8, 9, B of cell 3 (3) is defined as 0, 1, 8, 9, 10, 11. The PRBs that can be used according to Examples 1-3 are shown for each region as shown in FIG. 15.

In FIG. 15, UE1, ICU, which is the center region of Cell 1, may use 0 to 11, which is the entire band. At this time, resources from 0 to 11 can be prevented from occurring through proper power management.

In FIG. 15, in the case where UE1-23, CEU, which is the cell 1 region, in which the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 8, 9 are the remaining bands after subtracting B (1) from the total band Ω. Since it is a band common to B (2) and B (3), it can always use. In addition, since 4 and 5 are common parts of B (1) and B (2), they can be selectively used, and 0 and 1 can be selectively used as they are common parts of B (1) and B (3). As a result, resources assigned to UE1-23, CEU may be 8, 9, 0, 1, 4, 5. Of these, 8 and 9 are not used by the CEUs of other cells, so the possibility of interference is very low, and 0, 1, 4, and 5 may also be used in adjacent UE2-13, CEU, or UE3-12. have.

In FIG. 15, in the case where UE1-2 and CEU, which are the cell 1 regions, overlapped circles of cells 1 and 2 except for the overlapped portions of the three dotted circles of cells 1, 2, and 3, 6, Since 7, 8, and 9 are the bands common to B (2) among the remaining bands after subtracting B (1) from the total band Ω, they can always be used. In addition, since 4 and 5 are common parts of B (1) and B (2), they can be used selectively. As a result, resources assigned to UE1-2, CEU may be 6, 7, 8, 9, 4, 5. Of these, since 6, 7, 8, and 9 are not used by the CEUs of the cell 2, it is considered that the possibility of interference is very low, and 4 and 5 may selectively use the CEUs of the cell 2, so interference may occur. .

In FIG. 15, in the case where UE1-3 and CEU which are the cell 1 regions in the overlapped circle of the dotted lines of cell 1 and the cell 3 except for the overlapped portion of the three dotted circles of the cell 1, the cell 2 and the cell 3, 8, 9, 10, and 11 are the bands common to B (3) among the remaining bands after subtracting B (1) from the total band Ω. Since 0 and 1 are common parts of B (1) and B (3), they can be selectively used. Eventually, resources assigned to UE1-3 and CEU may be 0, 1, 8, 9, 10, and 11. Among them, 8, 9, 10, and 11 are not used by the CEU of the cell 3, so the possibility of interference is very low, and 0 and 1 may selectively use the CEU of the cell 3, so interference may occur. .

In FIG. 15, in the case where UE2-13, CEU, which is the cell 2 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other, 0 and 1 are the remaining bands after subtracting B (2) from the total band Ω. Since it is a band common to B (1) and B (3), it can always use. Since 4 and 5 are common parts of B (2) and B (1), they can be selectively used, and 8 and 9 can be selectively used because they are common parts of B (2) and B (3). As a result, resources assigned to UE2-13, CEU may be 0, 1, 4, 5, 8, 9. Of these, 0 and 1 are not used by the CEUs of other cells, so the possibility of interference is very low, and 4, 5, 8, and 9 may be used in adjacent UE1-23, CEU, or UE3-12. have.

In FIG. 15, in the case where UE3-12, CEU, which is the cell 3 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 4 and 5 are the remaining bands after subtracting B (3) from the total band Ω. Since the band is common to B (1) and B (2), it can always be used. Since 0 and 1 are common parts of B (3) and B (1), they can be selectively used, and 8 and 9 can be selectively used since they are common parts of B (3) and B (2). As a result, the resources assigned to UE3-12, CEU may be 0, 1, 4, 5, 8, 9. Of these, 4 and 5 are not used by the CEUs of other cells, so the possibility of interference is very low. 0, 1, 8, and 9 can also be used in adjacent UE1-23, CEU, or UE2-13. It may be.

In FIG. 15, 0 and 1 for UE2-1 and CEU, which are the cell 2 regions, in the portions where the dotted circles of Cell 1 and Cell 2 overlap except the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap. , 2, 3 are the bands common to B (1) among the remaining bands after subtracting B (2) from the total band Ω. 4 and 5 may be selectively used since they are common to B (2) and B (1). Eventually, resources assigned to UE2-1, CEU may be 0, 1, 2, 3, 4, 5. Among them, 0, 1, 2, and 3 are not used by the CEU of the cell 1, so the possibility of interference is very low, and 4 and 5 may selectively use the CEU of the cell 1, so interference may occur. .

In FIG. 15, in the case where UE3-1, CEU, which is a cell 3 region, overlaps the dotted circles of the cell 1 and the cell 3 except for the portion where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 2, 3 , 4, 5 are the bands common to B (1) among the remaining bands after subtracting B (3) from the total band Ω. Since 0 and 1 are common parts of B (3) and B (1), they can be selectively used. As a result, resources assigned to UE3-1, CEU may be 0, 1, 2, 3, 4, 5. Among them, 2, 3, 4, and 5 are not used by the CEU of cell 1, so the possibility of interference is very low, and 0, 1 may also selectively use the CEU of cell 1, so interference may occur. .

In FIG. 15, 0 and 1 for UE2-3 and CEU, which are cell 2 regions, where the dotted circles of cell 2 and cell 3 overlap except for the portions where the three dotted circles of cell 1, cell 2, and cell 3 overlap. , 10, and 11 are the bands common to B (3) among the remaining bands after subtracting B (2) from the total band Ω, and therefore can always be used. 8 and 9 can be used selectively since they are common to B (2) and B (3). As a result, resources assigned to UE2-3, CEU may be 0, 1, 8, 9, 10, 11. Among them, 0, 1, 10, and 11 are not used by the CEU of the cell 3, so the possibility of interference is very low, and 8 and 9 may selectively use the CEU of the cell 3, so interference may occur. .

In FIG. 15, in the case where UE3-2 and CEU which are the cell 3 regions in the overlapped portions of the cell 2 and the cell 3 except the overlapped portions of the three dotted circles of the cell 1, the cell 2, and the cell 3, 4 and 5 , 6 and 7 are always available because they are common to B (2) among the remaining bands after subtracting B (3) from the total band Ω. 8 and 9 can be used selectively since they are common to B (3) and B (2). As a result, resources assigned to UE3-2, CEU may be 4, 5, 6, 7, 8, 9. Among them, 4, 5, 6, and 7 are not used by the CEU of the cell 2, so the possibility of interference is very low, and 8 and 9 may selectively use the CEU of the cell 2, so interference may occur. .

In FIG. 15, UE2, ICU, which is the center region of cell 2, and UE, ICU, which is the center region of cell 3, may use the entire band like UE 1, ICU.

Example 1-4

Embodiments 1-4 are basically based on the above-described embodiments 1-3. The difference is that Equation (14) is modified to use:

C1B1-23, CEU = B (1) ∩ B (2) ∩ B (3) --- Equation (15)

According to the embodiments 1-4, resources available for each region are shown in FIG. 16.

Referring to FIG. 16, the center areas UE1 and ICU of cell 1 may use resources corresponding to UB1 and ICU. UB1, ICU may be the total resource? Assigned to the cell. The peripheral areas UE1 and CEU of the cell 1 may basically use resources corresponding to UB1 and CEU. UB1 and CEU may be resources corresponding to the remaining bands except for B (1) in the total resource Ω. In addition, the peripheral areas UE1 and CEU of Cell 1 may selectively use resources corresponding to C1B.

For example, the region (UE1-2, CEU) adjacent to cell 2 at the boundary of cell 1 can always use the band corresponding to the intersection of UB1, CEU and B (2), and C1B1-2, CEU, As in (12), a band corresponding to the intersection of B (1) and B (2) can be selectively used.

Similarly, the region close to cell 3 (UE1-3, CEU) at the boundary of cell 1 can always use the band corresponding to the intersection of UB1, CEU and B (3), and C1B1-3, CEU, that is, Equation (13) As described above, a band corresponding to the intersection of B (1) and B (3) can be selectively used.

The regions UE1-23.CEU adjacent to the cell 2 and the cell 3 at the boundary of the cell 1 can always use the band corresponding to the intersection of UB1, CEU and B (2) and B (3), and C1B1- 23, CEU, that is, the band corresponding to the intersection of B (1), B (2), B (3) can be selectively used as shown in Equation (15). In this case, since there is no common part, it can be seen that C1B1-23 and CEU do not have a corresponding band.

At this time, if all cells intend to use the C1B region, there may be 0 to 2 interference regions, and there may be two countermeasures.

The first countermeasure is to freely use C1B in situations where interference cancellation is possible, and the second countermeasure is to inform other cells of exclusive use in one cell using the X2 interface and prohibit the use of C1B in other cells that receive this information. There is a way to.

Looking at the embodiment 1-4 from the PRB perspective as shown in FIG.

In FIG. 8, B (1) of cell 1 is 0, 1, 2, 3, 4, 5, B (2) of cell 2 is 4, 5, 6, 7, 8, 9, B of cell 3 (3) is defined as 0, 1, 8, 9, 10, 11. 17 shows a PRB that can be used according to Examples 1-4 according to regions.

In FIG. 17, UE1 and ICU, which are the center regions of Cell 1, may use 0 to 11, which are all bands. At this time, resources from 0 to 11 can be prevented from occurring through proper power management.

In FIG. 17, in the case where UE1-23, CEU, which is the cell 1 region, in which the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 8, 9 are the remaining bands after subtracting B (1) from the total band Ω. Since it is a band common to B (2) and B (3), it can always use. Optionally, the available band may be C1B1-23, CEU as shown in Equation (15), but there is no corresponding part. As a result, resources assigned to UE1-23, CEU may be 8, 9, and 8, 9 are very unlikely to cause interference since CEUs of other cells are not used.

In FIG. 17, in the case where UE1-2 and CEU, which are the cell 1 regions, overlapped circles of cells 1 and 2 except for the portions where the three dotted circles of cells 1, 2 and 3 overlap each other, 6 , 7, 8, and 9 are the bands common to B (2) among the remaining bands after subtracting B (1) from the total band Ω. In addition, since 4 and 5 are common parts of B (1) and B (2), they can be used selectively. As a result, resources assigned to UE1-2, CEU may be 6, 7, 8, 9, 4, 5. Of these, since 6, 7, 8, and 9 are not used by the CEUs of the cell 2, it is considered that the possibility of interference is very low, and 4 and 5 may selectively use the CEUs of the cell 2, so interference may occur. .

In FIG. 17, in the case where UE1-3 and CEU which are the cell 1 regions in the overlapped circle of the dotted lines of cell 1 and the cell 3 except for the overlapped portion of the three dotted circles of the cell 1, the cell 2 and the cell 3, 8, 9, 10, and 11 are the bands common to B (3) among the remaining bands after subtracting B (1) from the total band Ω. Since 0 and 1 are common parts of B (1) and B (3), they can be selectively used. Eventually, resources assigned to UE1-3 and CEU may be 0, 1, 8, 9, 10, and 11. Among them, 8, 9, 10, and 11 are not used by the CEU of the cell 3, so the possibility of interference is very low, and 0 and 1 may selectively use the CEU of the cell 3, so interference may occur. .

In FIG. 17, in the case where UE2-13, CEU, which is the cell 2 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other, 0 and 1 are the remaining bands after subtracting B (2) from the total band Ω. Since it is a band common to B (1) and B (3), it can always use. Optionally, the usable band may be C1B2-13, CEU as shown in Eq. (15). As a result, resources assigned to UE2-13, CEU may be 0, 1, and since 0, 1 are not used by CEUs of other cells, the possibility of interference is very low.

In FIG. 17, in the case where UE3-12, CEU, which is the cell 3 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 4 and 5 are the remaining bands after subtracting B (3) from the total band Ω. Since the band is common to B (1) and B (2), it can always be used. Optionally, the available band may be C1B3-12, CEU as shown in Equation (15). As a result, resources assigned to UE3-12 and CEU may be 4 and 5, and since 4 and 5 are not used by CEUs of other cells, the possibility of interference is very low.

In FIG. 17, 0 and 1 for UE2-1 and CEU, which are the cell 2 regions, in the portions where the dotted circles of Cell 1 and Cell 2 overlap except the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap. , 2, 3 are the bands common to B (1) among the remaining bands after subtracting B (2) from the total band Ω. 4 and 5 may be selectively used since they are common to B (2) and B (1). Eventually, resources assigned to UE2-1, CEU may be 0, 1, 2, 3, 4, 5. Among them, 0, 1, 2, and 3 are not used by the CEU of the cell 1, so the possibility of interference is very low, and 4 and 5 may selectively use the CEU of the cell 1, so interference may occur. .

In FIG. 17, in the case where UE3-1, CEU, which is a cell 3 region, overlaps the dotted circles of the cell 1 and the cell 3 except for the portion where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 2, 3 , 4, 5 are the bands common to B (1) among the remaining bands after subtracting B (3) from the total band Ω. Since 0 and 1 are common parts of B (3) and B (1), they can be selectively used. As a result, resources assigned to UE3-1, CEU may be 0, 1, 2, 3, 4, 5. Among them, 2, 3, 4, and 5 are not used by the CEU of cell 1, so the possibility of interference is very low, and 0, 1 may also selectively use the CEU of cell 1, so interference may occur. .

In FIG. 17, 0 and 1 for UE2-3 and CEU, which are cell 2 regions, in a portion where the dotted circles of cell 2 and 3 overlap with each other except that the three dotted circles of cell 1, cell 2, and cell 3 overlap each other. , 10, and 11 are the bands common to B (3) among the remaining bands after subtracting B (2) from the total band Ω, and therefore can always be used. 8 and 9 can be used selectively since they are common to B (2) and B (3). As a result, resources assigned to UE2-3, CEU may be 0, 1, 8, 9, 10, 11. Among them, 0, 1, 10, and 11 are not used by the CEU of the cell 3, so the possibility of interference is very low, and 8 and 9 may selectively use the CEU of the cell 3, so interference may occur. .

In FIG. 17, 4 and 5 for UE3-2 and CEU, which are cell 3 regions, in which the dotted circles of Cell 2 and Cell 3 overlap except for the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap. , 6 and 7 are always available because they are common to B (2) among the remaining bands after subtracting B (3) from the total band Ω. 8 and 9 can be used selectively since they are common to B (3) and B (2). As a result, resources assigned to UE3-2, CEU may be 4, 5, 6, 7, 8, 9. Among them, 4, 5, 6, and 7 are not used by the CEU of the cell 2, so the possibility of interference is very low, and 8 and 9 may selectively use the CEU of the cell 2, so interference may occur. .

In FIG. 17, UE2, ICU, which is the center region of cell 2, and UE, ICU, which is the center region of cell 3, may use the entire band like UE 1, ICU.

Example 1-5

Example 1-5 defines a common unused band AXB that is not commonly used in all cells, and defines B ′ (i) which is a prohibited band of each cell based on the remaining bands excluding this AXB in all bands Ω. That's the way. That is, B (i) in the above-described embodiment may be expressed as the sum of AXB and B` (i).

For example, the cell's center region (ICU) uses the entire band, and the cell's peripheral region (CEU) basically uses the remaining bands except B ′ (i) and AXB, but some bands of B ′ (i) or This is an optional way to use AXB.

In this case, in the case of some bands of B ′ (i) or AXB selectively used, interference may occur, so it is necessary to consider whether interference cancellation is possible or whether exclusive use may be guaranteed through signaling.

According to the embodiments 1-5, resources available for each region are shown in FIG. 18.

Referring to FIG. 18, B (1), B (2), and B (3) indicate forbidden bands in each cell. And AXB represents a common unused band. Accordingly, in the case of B (1), it can be expressed as B (1) = AXB + B` (1). The UB always yields an available resource band, and C1B and A2B optionally indicate an available resource band. For example, C1B may be some band of B ′ (i), and A2B may be AXB.

If this is expressed through a concrete equation, it is as follows.

AXB = Frequency Common Unused Area --- Equation (16)

B (1) = AXB + B` (1) --- Equation (17)

B (2) = AXB + B` (2) --- Equation (18)

B (3) = AXB + B` (3) --- Equation (19)

UB1, ICU = Ω --- Equation (20)

UB1, CEU = Ω- [AXB + B` (1)] --- Equation (21)

UB1-2, CEU = UB1, CEU ∩ B` (2) --- Equation (22)

UB1-3, CEU = UB1, CEU ∩ B` (3) --- Equation (23)

UB1-23, CEU = UB1, CEU ∩ B` (2) ∩ B` (3) --- Equation (24)

C1B1-2, CEU = B` (1) ∩ B` (2) --- Equation (25)

C1B1-3, CEU = B` (1) ∩ B` (3) --- Equation (26)

C1B1-23, CEU = B` (1) ∩ B` (2) ∩ B` (3) --- Equation (27)

For example, an area (UE1-2, CEU) adjacent to cell 2 at the boundary of cell 1 may always use a band corresponding to the intersection of UB1, CEU and B` (2), and C1B1-2, CEU, that is, As in Equation (25), a band corresponding to the intersection of B ′ (1) and B ′ (2) may be selectively used. In addition, A2B corresponding to AXB may be selectively used.

Similarly, the region close to cell 3 (UE1-3, CEU) at the boundary of cell 1 can always use the band corresponding to the intersection of UB1, CEU and B` (3), and C1B1-3, CEU, ), A band corresponding to the intersection of B '(1) and B' (3) can be selectively used. In addition, A2B corresponding to AXB may be selectively used.

The regions UE1-23 and CEU adjacent to the cell 2 and the cell 3 at the boundary of the cell 1 can always use the band corresponding to the intersection of UB1, CEU and B ′ (2) and B ′ (3). A band corresponding to the intersection of B ′ (1), B ′ (2), and B ′ (3) may be selectively used as C1B1-23, CEU, that is, Equation (27). In this case, since there is no common part, it can be seen that C1B1-23 and CEU do not have a corresponding band. In addition, A2B corresponding to AXB may be selectively used.

At this time, if you intend to use C1B or A2B in all cells, there is a possibility that there will be 0 to 2 interference zones. There may be two countermeasures.

The first countermeasure is to freely use C1B or A2B if it is possible to cancel the interference, and the second countermeasure is to use the X2 interface to inform other cells of the exclusive use of one cell and to receive C1B or There is a way to prohibit the use of A2B.

Looking at the embodiment 1-5 from the PRB perspective as shown in FIG.

In FIG. 20, B (1) of cell 1 is 0, 1, 2, 3, 4, 5, 6, B (2) of cell 2 is 0, 1, 2, 6, 7, 8, 9, B (3) of cell 3 is defined as 0, 1, 2, 3, 4, 9, 10, 11. At this time, AXB is equal to 0, 1, 2. Therefore, B '(1) is equal to 3, 4, 5, 6.

19 shows a PRB that can be used according to Example 1-5 according to regions.

In FIG. 19, UE1, ICU, which is the center region of Cell 1, may use 0 to 11, which is the entire band. At this time, resources from 0 to 11 can be prevented from occurring through proper power management.

In FIG. 19, in the case where UE1-23 and CEU, which are the cell 1 regions at the portions where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 9 represents B in the remaining bands after subtracting B (1) from the total band? The band is common to `(2) and B` (3) and can always be used. Optionally, the first available band may be C1B1-23, CEU as shown in Eq. (27). Optionally, the second available band may be 0, 1, or 2, which is AXB. As a result, resources assigned to UE1-23, CEU may be 0, 1, 2, 9. Of these, 9 is not used by the CEUs of other cells, so the possibility of interference is very low, and 0, 1, and 2 may selectively use CEUs of other cells, so interference may occur.

In FIG. 19, in the case where UE1-2 and CEU which are the cell 1 regions in the overlapping circle of the dotted lines of cell 1 and cell 2 except for the overlapping portion of the three dotted circles of cell 1, the cell 2 and the cell 3, 7, 8 and 9 are always available because they are common to B '(2) among the remaining bands after subtracting B (1) from the total band Ω. 6 is a common part of B '(1) and B' (2), and can be used selectively. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, the resources assigned to UE1-2, CEU may be 0, 1, 2, 6, 7, 8, 9. Among them, 7, 8, and 9 are not used by the CEUs of the cell 2, so the possibility of interference is very low. Can be.

In FIG. 19, in the case where UE1-3 and CEU which are the cell 1 regions in the overlapped circles of the cells 1 and 3 except for the overlapped portions of the three dotted circles of the cells 1, 2 and 3, 9, 10 and 11 are always available because they are common to B ′ (3) among the remaining bands after subtracting B (1) from the total band Ω. And 3 is a common part of B` (1) and B` (3) can be used selectively. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, resources assigned to UE1-3 and CEU may be 0, 1, 2, 3, 9, 10, and 11. Of these, 9, 10, and 11 are not used by the CEUs of cell 3, so the possibility of interference is very low, and 0, 1, 2, and 3 may selectively use the CEUs of cell 3, so interference may occur. Can be.

In FIG. 19, in the case where UE2-13, CEU, which is the cell 2 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 3 is B in the remaining bands after subtracting B (2) from the total band Ω. The band is common to `(1) and B` (3) and can always be used. Optionally, the first available band may be C1B2-13, CEU as shown in Eq. (27). Optionally, the second available band may be 0, 1, or 2, which is AXB. As a result, resources assigned to UE2-13, CEU may be 0, 1, 2, 3. Of these, since 3 is not used by CEUs of other cells, the possibility of interference is very low, and 0, 1, and 2 may selectively use CEUs of other cells, and thus interference may occur.

In FIG. 19, in the case where UE3-12, CEU, which is the cell 3 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 6 represents B in the remaining bands after subtracting B (3) from the total band Ω. The band is common to `(1) and B` (2), so it can always be used. Optionally, the first available band may be C1B3-12, CEU as shown in Eq. (27). Optionally, the second available band may be 0, 1, or 2, which is AXB. As a result, resources assigned to UE3-12, CEU may be 0, 1, 2, 6. Since 6 of the CEUs of other cells are not used, the possibility of interference is very low, and 0, 1, and 2 may selectively use CEUs of other cells, so interference may occur.

In FIG. 19, 3 and 4 in the case of UE2-1 and CEU, which are the cell 2 regions, in which the dotted circles of Cell 1 and Cell 2 overlap except for the portions where the three dotted circles of Cell 1, Cell 2 and Cell 3 overlap each other. , 5 is a band common to B '(1) among the remaining bands after subtracting B (2) from the total band Ω. 6 is a common part of B '(2) and B' (1) and can be used selectively. In addition, since 0, 1, and 2 are AXB, they can be selectively used. Eventually, resources assigned to UE2-1, CEU may be 0, 1, 2, 3, 4, 5, 6. Of these, since 3, 4, and 5 are not used by the CEU of cell 1, the possibility of interference is very low, and 0, 1, 2, and 6 may selectively use the CEU of 1, which may cause interference. have.

In FIG. 19, 4 and 5 for UE3-1 and CEU, which are the cell 3 regions, in the portions where the dotted circles of Cell 1 and Cell 3 overlap except the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap. , 6 is a band common to B '(1) among the remaining bands after subtracting B (3) from the total band Ω. 3 is a common part of B '(3) and B' (1) and can be used selectively. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, resources assigned to UE3-1, CEU may be 0, 1, 2, 3, 4, 5, 6. Of these, 4, 5, and 6 are not used by the CEUs of cell 1, and therefore, the possibility of interference is very low. It may be.

In FIG. 19, in the case where UE2-3, CEU, which is the cell 2 region, overlaps the dotted circles of the cell 2 and the cell 3 except for the portions where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 3, 10 , 11 is a band common to B '(3) among the remaining bands after subtracting B (2) from the total band Ω. And since 9 is a common part of B` (2) and B` (3), it can be selectively used. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, resources assigned to UE2-3 and CEU may be 0, 1, 2, 3, 9, 10, 11. Of these, since 3, 10, and 11 are not used by the CEUs of the cell 3, the possibility of interference may be considered very low. It may be.

In FIG. 19, in the case where UE3-2 and CEU which are cell 3 regions in the overlapped portions of the cell 2 and the cell 3 except the overlapped portions of the three dotted circles of the cell 1, the cell 2 and the cell 3, 6 and 7 , 8 is a band common to B '(2) among the remaining bands after subtracting B (3) from the total band Ω. And since 9 is a common part of B` (3) and B` (2), it can be selectively used. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, the resources assigned to UE3-2, CEU may be 0, 1, 2, 6, 7, 8, 9. Among them, 6, 7, 8 are not used by the CEU of the cell 2, so the possibility of interference is very low, and 0, 1, 2, and 9 can selectively use the CEU of the cell 2, so interference may occur. It may be.

In FIG. 19, UE2, ICU, which is the center region of cell 2, and UE, ICU, which is the center region of cell 3, may use the entire band like UE 1, ICU.

Example 1-6

Example 1-6 basically uses the same method as Example 1-5. However, do not use AXB for areas where three or more cells overlap.

For example, the cell's center region (ICU) uses the entire band, and the cell's peripheral region (CEU) basically uses the remaining bands except B ′ (i) and AXB, but some bands of B ′ (i) or This is an optional way to use AXB. However, AXB is not used for an area where three or more cells overlap.

21, the resources available for each region are shown in FIG. 21.

Referring to FIG. 21, B (1), B (2), and B (3) indicate forbidden bands in each cell. And AXB represents a common unused band. Accordingly, in the case of B (1), it can be expressed as B (1) = AXB + B` (1). UB always yields an available resource band, and C1B and C2B optionally indicate an available resource band. For example, C1B may be some band of B ′ (i), and C2B may be AXB.

If this is expressed through a specific equation, it is the same as the equations (16) to (27).

For example, an area (UE1-2, CEU) adjacent to cell 2 at the boundary of cell 1 may always use a band corresponding to the intersection of UB1, CEU and B` (2), and C1B1-2, CEU, that is, As in Equation (25), a band corresponding to the intersection of B ′ (1) and B ′ (2) may be selectively used. In addition, C2B corresponding to AXB may be selectively used.

Similarly, the region close to cell 3 (UE1-3, CEU) at the boundary of cell 1 can always use the band corresponding to the intersection of UB1, CEU and B` (3), and C1B1-3, CEU, ), A band corresponding to the intersection of B '(1) and B' (3) can be selectively used. In addition, C2B corresponding to AXB may be selectively used.

The regions UE1-23 and CEU adjacent to the cell 2 and the cell 3 at the boundary of the cell 1 can always use the band corresponding to the intersection of UB1, CEU and B ′ (2) and B ′ (3). A band corresponding to the intersection of B ′ (1), B ′ (2), and B ′ (3) may be selectively used as C1B1-23, CEU, that is, Equation (27). In this case, since there is no common part, it can be seen that C1B1-23 and CEU do not have a corresponding band. And C2B corresponding to AXB is not used here, unlike Examples 1-5.

In this case, if you intend to use C1B or C2B in all cells, there may be 0 to 2 interference regions, and there may be two measures.

The first countermeasure is to freely use C1B or C2B if interference cancellation is possible, and the second countermeasure is to inform other cells of the exclusive use of one cell using the X2 interface, and the C1B or There is a way to prohibit the use of C2B.

Looking at the embodiment 1-6 from the PRB perspective as shown in FIG.

In FIG. 20, B (1) of cell 1 is 0, 1, 2, 3, 4, 5, 6, B (2) of cell 2 is 0, 1, 2, 6, 7, 8, 9, B (3) of cell 3 is defined as 0, 1, 2, 3, 4, 9, 10, 11. At this time, AXB is equal to 0, 1, 2. Therefore, B '(1) is equal to 3, 4, 5, 6.

22 shows PRBs that can be used according to Examples 1-6 according to regions.

In FIG. 22, UE1 and ICU, which are the center regions of Cell 1, may use 0 to 11, which are all bands. At this time, resources from 0 to 11 can be prevented from occurring through proper power management.

In FIG. 22, in the case where UE1-23 and CEU, which are the cell 1 regions at the portions where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 9 represents B in the remaining bands after subtracting B (1) from the total band? The band is common to `(2) and B` (3) and can always be used. Optionally, the available band may be C1B1-23, CEU as shown in Equation (27), but there is no corresponding part. As a result, the resource assigned to UE1-23, CEU may be 9. Since 9 is not used by the CEU of another cell, the possibility of interference is very low.

In FIG. 22, in the case where UE1-2 and CEU which are the cell 1 regions in the overlapped circles of cells 1 and 2 except for the overlapped portions of the three dotted circles of Cell 1, Cell 2 and Cell 3, 7, 8 and 9 are always available because they are common to B '(2) among the remaining bands after subtracting B (1) from the total band Ω. 6 is a common part of B '(1) and B' (2), and can be used selectively. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, the resources assigned to UE1-2, CEU may be 0, 1, 2, 6, 7, 8, 9. Among them, 7, 8, and 9 are not used by the CEUs of the cell 2, so the possibility of interference is very low, and 0, 1, 2, and 6 may selectively use the CEUs of the cell 2, which may cause interference. Can be.

In FIG. 22, in the case where UE1-3 and CEU which are the cell 1 regions in the overlapped circles of the cells 1 and 3 except for the overlapped portions of the three dotted circles of the cell 1, the cell 2 and the cell 3, 9, 10 and 11 are always available because they are common to B ′ (3) among the remaining bands after subtracting B (1) from the total band Ω. And 3 is a common part of B` (1) and B` (3) can be used selectively. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, resources assigned to UE1-3 and CEU may be 0, 1, 2, 3, 9, 10, and 11. Of these, 9, 10, and 11 are not used by the CEUs of cell 3, so the possibility of interference is very low, and 0, 1, 2, and 3 may selectively use the CEUs of cell 3, so interference may occur. Can be.

In FIG. 22, in the case where UE2-13, CEU, which is the cell 2 region, in which the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 3 is B in the remaining bands after subtracting B (2) from the total band Ω. The band is common to `(1) and B` (3) and can always be used. Optionally, the available band may be C1B2-13, CEU as shown in Equation (27), but there is no corresponding part. As a result, the resource assigned to UE2-13, CEU may be three. Since 3 is not used by the CEU of another cell, the possibility of interference is very low.

In FIG. 22, in the case where UE3-12, CEU, which is the cell 3 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 6 represents B in the remaining bands after subtracting B (3) from the total band Ω. The band is common to `(1) and B` (2), so it can always be used. Optionally, the available band may be C1B3-12, CEU as shown in Eq. (27). As a result, the resource assigned to UE3-12, CEU may be 6. Since 6 is not used by the CEU of another cell, the possibility of interference is very low.

In FIG. 22, in the case where UE2-1, CEU, which is the cell 2 region, overlaps the dotted circles of the cell 1 and the cell 2 except for the overlapped portions of the three dotted circles of the cell 1, the cell 2, and the cell 3, 3 and 4 , 5 is a band common to B '(1) among the remaining bands after subtracting B (2) from the total band Ω. 6 is a common part of B '(2) and B' (1) and can be used selectively. In addition, since 0, 1, and 2 are AXB, they can be selectively used. Eventually, resources assigned to UE2-1, CEU may be 0, 1, 2, 3, 4, 5, 6. Of these, since 3, 4, and 5 are not used by the CEU of cell 1, the possibility of interference is very low, and 0, 1, 2, and 6 may selectively use the CEU of 1, which may cause interference. have.

In FIG. 22, in the case where UE3-1, CEU, which is a cell 3 region, overlaps the dotted circles of the cell 1 and the cell 3 except for the portion where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 4, 5 , 6 is a band common to B '(1) among the remaining bands after subtracting B (3) from the total band Ω. 3 is a common part of B '(3) and B' (1) and can be used selectively. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, resources assigned to UE3-1, CEU may be 0, 1, 2, 3, 4, 5, 6. Of these, 4, 5, and 6 are not used by the CEUs of cell 1, so the possibility of interference is very low, and 0, 1, 2, and 3 may selectively use the CEUs of cell 1, causing interference. It may come to life.

In FIG. 22, in the case where UE2-3, CEU, which is the cell 2 region, overlaps the dotted circles of the cell 2 and the cell 3 except for the portions where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 3, 10 , 11 is a band common to B '(3) among the remaining bands after subtracting B (2) from the total band Ω. And since 9 is a common part of B` (2) and B` (3), it can be selectively used. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, resources assigned to UE2-3 and CEU may be 0, 1, 2, 3, 9, 10, 11. Of these, since 3, 10, and 11 are not used by the CEUs of the cell 3, the possibility of interference may be considered very low. It may be.

In FIG. 22, in the case where UE3-2 and CEU which are the cell 3 regions in the overlapped portions of the cell 2 and the cell 3 except the overlapped portions of the three dotted circles of the cell 1, the cell 2, and the cell 3, 6, 7 , 8 is a band common to B '(2) among the remaining bands after subtracting B (3) from the total band Ω. And since 9 is a common part of B` (3) and B` (2), it can be selectively used. In addition, since 0, 1, and 2 are AXB, they can be selectively used. As a result, the resources assigned to UE3-2, CEU may be 0, 1, 2, 6, 7, 8, 9. Among them, 6, 7, 8 are not used by the CEU of the cell 2, so the possibility of interference is very low, and 0, 1, 2, and 9 can selectively use the CEU of the cell 2, so interference may occur. It may be.

In FIG. 22, UE2, ICU, which is the center region of cell 2, and UE, ICU, which is the center region of cell 3, may use the entire band like UE 1, ICU.

Example 2

The above embodiments assume a case where sectoring is not performed in a cell. However, the above-described embodiments may be equally applicable to sectoring, and FIG. 23 illustrates when such sectoring is considered.

Example 3-1

In the above-described embodiments, it is assumed that the same total resource Ω is allocated to all cells. However, the above-described embodiments may be applied even if there is a band difference in the overall resource Ω.

For example, the case of Ω1 ≠ Ω2, Ω1 ≠ Ω3, and Ω2 = Ω3 from the PRB point of view is shown in FIG. 24.

Referring to FIG. 24, it can be seen that PRBs corresponding to 0 to 11 are commonly allocated to cells 1, 2, and 3, but in the case of cell 1, PRBs corresponding to 12 to 15 are further included. As such, when Ω i is not the same, cell 1 may recognize PRBs corresponding to 12 to 15 as B (2) of cell 2 and B (3) of cell 3.

The case where Ω i is not the same is applied to the above-described Examples 1-4, and the available PRBs are shown for each region as shown in FIG. 25.

In FIG. 25, UE1, ICU, which is the center region of Cell 1, may use 0 to 15, which is an entire band. In this case, resources from 0 to 11 can be prevented from causing interference through proper power management, and 12 to 15 can be considered completely free from interference because they are not used in other cells.

In FIG. 25, in the case where UE1-23, CEU, which is the cell 1 region, at the overlapping portions of three dotted circles of Cell 1, Cell 2, and Cell 3, 8 and 9 are the remaining bands after subtracting B (1) from the total band Ω. Since it is a band common to B (2) and B (3), it can always use. Further, 12, 13, 14, and 15 are bands not used by cells 2 and 3, and thus can always be used. In this case, cell 1 may recognize that 12, 13, 14, and 15 are included in B (2) and B (3). And optionally available band can be C1B1-23, CEU as shown in equation (15), it can be seen that there is no corresponding part. As a result, resources assigned to UE1-23, CEU may be 8, 9, 12, 13, 14, 15, and this band is very unlikely to cause interference since the CEU of another cell is not used.

In FIG. 25, in the case where UE1-2 and CEU which are the cell 1 areas in the overlapping circle of the dotted lines of cell 1 and cell 2 except for the overlapping portion of the three dotted circles of cell 1, the cell 2 and the cell 3, 6, Since 7, 8, and 9 are the bands common to B (2) among the remaining bands after subtracting B (1) from the total band Ω, they can always be used. 12, 13, 14, and 15 will also be recognized as B (2) and can always be used. In addition, since 4 and 5 are common parts of B (1) and B (2), they can be used selectively. As a result, the resources assigned to the UE1-2, CEU may be 4, 5, 6, 7, 8, 9, 12, 13, 14, 15. Among them, 8, 9, 12, 13, 14, and 15 are not used by the CEU of cell 2, so the possibility of interference is very low. This can happen.

In FIG. 25, in the case where UE1-3 and CEU which are the cell 1 areas in the overlapping circle of the dotted lines of cell 1 and cell 3 except for the overlapping portion of the three dotted circles of cell 1, the cell 2 and the cell 3, 8, 9, 10, and 11 are the bands common to B (3) among the remaining bands after subtracting B (1) from the total band Ω. 12, 13, 14, and 15 will also be recognized as B (3) and can always be used. In addition, since 0 and 1 are common parts of B (1) and B (3), they can be used selectively. As a result, resources assigned to UE1-3 and CEU may be 0, 1, 8, 9, 10, 11, 12, 13, 14, and 15. Among them, 8, 9, 10, 11, 12, 13, 14, and 15 are not used by the CEU of cell 3, so the possibility of interference is very low. Interference may occur as it can be used.

In FIG. 25, in the case where UE2-13, CEU, which is the cell 2 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other, 0 and 1 are the remaining bands after subtracting B (2) from the total band Ω. Since it is a band common to B (1) and B (3), it can always use. Optionally, the usable band may be C1B2-13, CEU as shown in Eq. (15). As a result, resources assigned to UE2-13, CEU may be 0, 1, and since 0, 1 are not used by CEUs of other cells, the possibility of interference is very low.

In FIG. 25, in the case where UE3-12, CEU, which is the cell 3 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 4 and 5 are the remaining bands after subtracting B (3) from the total band Ω. Since the band is common to B (1) and B (2), it can always be used. Optionally, the available band may be C1B3-12, CEU as shown in Eq. (15). As a result, resources assigned to UE3-12 and CEU may be 4 and 5, and since 4 and 5 are not used by CEUs of other cells, the possibility of interference is very low.

In FIG. 25, 0 and 1 for UE2-1 and CEU, which are the cell 2 regions, in the portions where the dotted circles of Cell 1 and Cell 2 overlap except the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap. , 2, 3 are the bands common to B (1) among the remaining bands after subtracting B (2) from the total band Ω. 4 and 5 may be selectively used since they are common to B (2) and B (1). Eventually, resources assigned to UE2-1, CEU may be 0, 1, 2, 3, 4, 5. Among them, 0, 1, 2, and 3 are not used by the CEU of the cell 1, so the possibility of interference is very low, and 4 and 5 may selectively use the CEU of the cell 1, so interference may occur. .

In FIG. 25, for the UE3-1 and CEU which are the cell 3 regions in the portions where the dotted circles of the cell 1 and the cell 3 overlap except the portions where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 2, 3 , 4, 5 are the bands common to B (1) among the remaining bands after subtracting B (3) from the total band Ω. Since 0 and 1 are common parts of B (3) and B (1), they can be selectively used. As a result, resources assigned to UE3-1, CEU may be 0, 1, 2, 3, 4, 5. Among them, 2, 3, 4, and 5 are not used by the CEU of cell 1, so the possibility of interference is very low, and 0, 1 may also selectively use the CEU of cell 1, so interference may occur. .

In FIG. 25, 0 and 1 for UE2-3 and CEU, which are cell 2 regions, in the portions where the dotted circles of cell 2 and cell 3 overlap except for the portions where the three dotted circles of cell 1, cell 2, and cell 3 overlap. , 10, and 11 are the bands common to B (3) among the remaining bands after subtracting B (2) from the total band Ω, and therefore can always be used. 8 and 9 can be used selectively since they are common to B (2) and B (3). As a result, resources assigned to UE2-3, CEU may be 0, 1, 8, 9, 10, 11. Among them, 0, 1, 10, and 11 are not used by the CEU of the cell 3, so the possibility of interference is very low, and 8 and 9 may selectively use the CEU of the cell 3, so interference may occur. .

In FIG. 25, for the UE3-2 and CEU which are the cell 3 regions in the overlapped portions of the cell 2 and the cell 3 except the overlapped portions of the three dotted circles of the cell 1, the cell 2, and the cell 3, 4 and 5 , 6 and 7 are always available because they are common to B (2) among the remaining bands after subtracting B (3) from the total band Ω. 8 and 9 can be used selectively since they are common to B (3) and B (2). As a result, resources assigned to UE3-2, CEU may be 4, 5, 6, 7, 8, 9. Among them, 4, 5, 6, and 7 are not used by the CEU of the cell 2, so the possibility of interference is very low, and 8 and 9 may selectively use the CEU of the cell 2, so interference may occur. .

In FIG. 25, UEs 2 and ICU which are the center regions of cell 2 and UEs and ICU which are the center regions of cell 3 may use 0 to 11.

Example 3-2

Example 3-2 relates to the case where Ω1 ≠ Ω2, Ω1 ≠ Ω3, and Ω2 ≠ Ω3.

For example, the case of Ω1 ≠ Ω2, Ω1 ≠ Ω3, Ω2 ≠ Ω3 from the PRB point of view is shown in FIG. 26.

Referring to FIG. 26, it can be seen that PRBs of cells 1 through 0, cell 2 through 0 through 13, and cell 3 through 0 through 11 are allocated. Thus, when Ω i is not the same, cell 1 can recognize 14, 15 as B (2) of cell 2, and 12, 13, 14, 15 can be recognized as B (3) of cell 3 have.

The case where Ω i is not the same is applied to the above-described Examples 1-4, and the available PRBs are shown for each region as shown in FIG. 27.

In FIG. 27, UE1, ICU, which is the center region of Cell 1, may use 0 to 15, which are all bands. At this time, it is possible to prevent interference from occurring through proper power management in 0 to 11, 12, and 13, and 14 and 15 are completely free from interference because they are not used in other cells.

In FIG. 27, in the case where UE1 -23 and CEU, which are the cell 1 regions, at the overlapping portions of the three dotted circles of the cell 1, the cell 2, and the cell 3, 8 and 9 are the remaining bands after subtracting B (1) from the total band? Since it is a band common to B (2) and B (3), it can always use. Further, since 14 and 15 are bands not used by cells 2 and 3, they can always be used. In this case, cell 1 may recognize 14 and 15 as B (2) of cell 2 and 12, 13, 14 and 15 as B (3) of cell 3. And optionally available band can be C1B1-23, CEU as shown in equation (15), it can be seen that there is no corresponding part. As a result, resources assigned to UE1-23, CEU may be 8, 9, 14, 15, and this band is not used by CEUs of other cells, and thus the possibility of interference is very low.

In FIG. 27, in the case where UE1-2 and CEU which are the cell 1 areas in the overlapped circle of the dotted lines of cell 1 and the cell 2 except for the overlapped portion of the three dotted circles of the cell 1, the cell 2 and the cell 3, 6, Since 7, 8, and 9 are the bands common to B (2) among the remaining bands after subtracting B (1) from the total band Ω, they can always be used. And 14, 15 degrees will be recognized as B (2) can always be used. In addition, since 4 and 5 are common parts of B (1) and B (2), they can be used selectively. As a result, the resources assigned to UE1-2, CEU may be 4, 5, 6, 7, 8, 9, 14, 15. Among them, 6, 7, 8, 9, 14, and 15 are not used by the CEU of cell 2, and thus, the possibility of interference is very low. This can happen.

In FIG. 27, in the case where UE1-3, CEU which is the cell 1 region in the overlapped circle of the dotted lines of the cell 1 and the cell 3 except for the overlapped portion of the three dotted circles of the cell 1, the cell 2 and the cell 3, 8, 9, 10, and 11 are the bands common to B (3) among the remaining bands after subtracting B (1) from the total band Ω. 12, 13, 14, and 15 will also be recognized as B (3) and can always be used. In addition, since 0 and 1 are common parts of B (1) and B (3), they can be used selectively. As a result, resources assigned to UE1-3 and CEU may be 0, 1, 8, 9, 10, 11, 12, 13, 14, and 15. Among them, 8, 9, 10, 11, 12, 13, 14, and 15 are not used by the CEU of cell 3, so the possibility of interference is very low. Interference may occur as it can be used.

In FIG. 27, in the case where UE2-13, CEU, which is the cell 2 region, in which the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap each other, 0 and 1 are the remaining bands after subtracting B (2) from the total band Ω. It is always available because it is a band common to B (1) and B (3). Optionally, the usable band may be C1B2-13, CEU as shown in Eq. (15). As a result, resources assigned to UE2-13, CEU may be 0, 1, and since 0, 1 are not used by CEUs of other cells, the possibility of interference is very low.

In FIG. 27, in the case where UE3-12, CEU, which is the cell 3 region, where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap, 4 and 5 are the remaining bands after subtracting B (3) from the total band Ω. Since the band is common to B (1) and B (2), it can always be used. Optionally, the available band may be C1B3-12, CEU as shown in Equation (15). As a result, resources assigned to UE3-12 and CEU may be 4 and 5, and since 4 and 5 are not used by CEUs of other cells, the possibility of interference is very low.

In FIG. 27, 0 and 1 for UE2-1 and CEU, which are the cell 2 regions, in the portions where the dotted circles of Cell 1 and Cell 2 overlap except the portions where the three dotted circles of Cell 1, Cell 2, and Cell 3 overlap. , 2, 3 are the bands common to B (1) among the remaining bands after subtracting B (2) from the total band Ω. 4 and 5 may be selectively used since they are common to B (2) and B (1). Eventually, resources assigned to UE2-1, CEU may be 0, 1, 2, 3, 4, 5. Among them, 0, 1, 2, and 3 are not used by the CEU of the cell 1, so the possibility of interference is very low, and 4 and 5 may selectively use the CEU of the cell 1, so interference may occur. .

In FIG. 27, in the case where UE3-1, CEU, which is a cell 3 region, overlaps the dotted circles of the cell 1 and the cell 3 except for the portion where the three dotted circles of the cell 1, the cell 2, and the cell 3 overlap, 2, 3 , 4, 5 are the bands common to B (1) among the remaining bands after subtracting B (3) from the total band Ω. Since 0 and 1 are common parts of B (3) and B (1), they can be selectively used. As a result, resources assigned to UE3-1, CEU may be 0, 1, 2, 3, 4, 5. Among them, 2, 3, 4, and 5 are not used by the CEU of cell 1, so the possibility of interference is very low, and 0, 1 may also selectively use the CEU of cell 1, so interference may occur. .

In FIG. 27, 0 and 1 for UE2-3 and CEU, which are cell 2 regions, where the dotted circles of cell 2 and cell 3 overlap except for the portions where the three dotted circles of cell 1, cell 2, and cell 3 overlap. , 10, and 11 are the bands common to B (3) among the remaining bands after subtracting B (2) from the total band Ω, and therefore can always be used. 8 and 9 can be used selectively since they are common to B (2) and B (3). As a result, resources assigned to UE2-3, CEU may be 0, 1, 8, 9, 10, 11. Among them, 0, 1, 10, and 11 are not used by the CEU of the cell 3, so the possibility of interference is very low, and 8 and 9 may selectively use the CEU of the cell 3, so interference may occur. .

In FIG. 27, in the case where UE3-2 and CEU which are the cell 3 regions in the overlapped portions of the cell 2 and the cell 3 except the overlapped portions of the three dotted circles of the cell 1, the cell 2 and the cell 3, 4 and 5 , 6 and 7 are always available because they are common to B (2) among the remaining bands after subtracting B (3) from the total band Ω. 8 and 9 can be used selectively since they are common to B (3) and B (2). As a result, resources assigned to UE3-2, CEU may be 4, 5, 6, 7, 8, 9. Among them, 4, 5, 6, and 7 are not used by the CEU of the cell 2, so the possibility of interference is very low, and 8 and 9 may selectively use the CEU of the cell 2, so interference may occur. .

In FIG. 27, UE2 and ICU, which are the center regions of Cell 2, may use 0 to 13, and 0 to 11 may be used as the UE3 and ICU, which are center regions of Cell 3.

Example 4

The fourth embodiment defines a JB band as shown in the following equation, and optionally allows the CEU of Cell i to exclusively use the JB band. If the CEU intends to use the JB band exclusively, inter-cell signaling is involved.

JB1-2, CEU = {UB1, CEU ∩ UB2, CEU}-JB1-23, CEU --- Equation (28)

JB1-3, CEU = {UB1, CEU ∩ UB3, CEU}-JB1-23, CEU --- Formula (29)

JB1-23, CEU = UB1, CEU ∩ UB2, CEU ∩ UB3, CEU --- Eq. (30)

For example, in the above-described embodiments 1-1 to 1-6, it is possible to selectively specify the JB in the peripheral region of the cell.

For example, in the PRB shown in FIG. 13, when JB is applied to Examples 1-2, the same results are used as in FIGS. 28 and 29.

In addition, in the PRB shown in FIG. 8, when JB is applied to Examples 1-3, it is the same as that of FIGS. 30 and 31.

In addition, in the PRB shown in FIG. 8, when the JB is applied to Examples 1-4, it is similar to FIGS. 32 and 33.

 In addition, in the PRB shown in FIG. 20, when JB is applied to Example 1-5, it is the same as FIG. 34 and FIG.

In addition, in the PRB shown in FIG. 20, when JB is applied to Examples 1-6, it is the same as FIG. 36 and FIG.

The fourth embodiment additionally defines the JB band that can be selectively used in the above-described first embodiment, and the description of each situation has been described in detail above, and thus a detailed description thereof will be omitted.

Example 5

Embodiment 5 can be thought of as a combination of Embodiments 3 and 4 described above. That is, even if JB is additionally defined, Example 3-1 and Example 3-2 may be equally applied.

For example, referring to FIG. 38, even if all resources allocated to each cell are different from each other, it is possible to designate a band that can always be used and a band that can be selectively used for each region, and determine interference characteristics for each band. have.

So far, the cell has been divided into a plurality of regions, and various methods of assigning resources to each region and what interference characteristics of the designated resources have been described. As described above, this process is performed by the acquisition unit 501 according to an embodiment of the present invention to receive messages of Type 1, 2, 3, 4, etc., and the determination unit 502 described above using the received message. As an example, it is possible to designate resources by region and to impart interference characteristics by resources.

While describing the above embodiments, the interference characteristics have not been described in detail. However, it has been described whether or not the resource has a high or low likelihood of interference in each resource available for each region, and it is possible to give various interference characteristics according to the likelihood of such interference.

According to an embodiment of the present invention, the interference characteristic is given to the first interference characteristic which is given to the resource which does not occur, and which has the possibility of interference but is relatively less likely and which can avoid the interference by power control. There is a second interference characteristic, the likelihood of occurrence of interference, and the likelihood is relatively high, but there is a third interference characteristic, the likelihood of occurrence of interference, and the likelihood of the interference is given to a resource that can avoid interference by physical interference cancellation with the terminal. A fourth interference characteristic is given to a resource that can be guaranteed exclusive use through an X2 message.

For example, referring to FIG. 12, it can be seen that the PRBs designated for UE1-2 and CEU are 0, 1, 2, 8, 9, and 10 according to the embodiment 1-2. Here, since 9 and 10 are not used in cells 2 and 3, 9 and 10 have a very low possibility of interference, and therefore, it is possible to give a first interference characteristic. In addition, in case of 8, since it is not used in the cell 2, since the possibility of interference is very low in the relationship with the cell 2, the first interference characteristic may be given. Alternatively, since interference may occur relative to 9 and 10, a second interference characteristic may be given. In the case of 0, 1, and 2, since the common use band, interference cancellation is possible, the third interference characteristic may be given, and if the exclusive use can be guaranteed through the X2 message, the fourth interference characteristic may be given.

Resource allocation scheduling and power management are performed according to the resources for each region and interference characteristics for each resource determined as described above.

For example, if a terminal is located in a certain area, the controller 503 according to an embodiment of the present invention may operate allocation scheduling according to an interference characteristic applied to a resource designated in the corresponding area. In the above example, for example, it is possible to preferentially schedule 8 with the first interference characteristic and later schedule 0, 1, 2 with the third or fourth interference characteristic.

In addition, in power management, the maximum power for each resource can be operated differently according to the interference characteristics. For example, in the above example, it is possible to manage 8 at maximum power and 9, 10 at less power.

The allocation scheduling and power management will be described in more detail as follows.

Example 6

The interference characteristics are classified into four categories as follows. For example, in the above-described embodiment, it is possible to give the following interference characteristics to the PRB designated for each region.

-IFZ (Interference Free Zone): First interference characteristic (if there is no interference)

-LZ (Low Interference Zone): ash 2 interference characteristics (if interference can be avoided by proper power adjustment)

Interference Cancellation Zone (ICZ): Third interference characteristic (when a specific terminal has interference cancellation capability in a corresponding region)

-High Interference Zone (HIZ): 4th interference characteristic (if the exclusive use can be guaranteed by exchanging X2 messages between cells)

In addition, according to the above-described interference generation characteristics, the usable band and the unused band of the neighboring cell CEU can be distinguished from the ICU and CEU of the serving cell as shown in the following table.

Based on such interference characteristics, transmission power control may be performed according to a region to which a terminal belongs, and for example, maximum transmission power may be controlled as follows.

IFZ = ICZ = LIZ = HIZ

The maximum transmit power limit may use a method of selecting any value among predetermined values. For example, RZTPthreshold is defined as a threshold value, and one of these values is selected, and IFZ is +3, ICZ is +1, LIZ is -3, and HIZ is -7.

RZTPthreshold = {11, -10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, + 1, + 2, + 3}

There can be various ways to initialize such RZTPthreshold, one of which is the method that Central Node directly initializes and delivers to each Node. In the future, each node can be adjusted according to the situation of the node. In addition, neighboring nodes may be notified of adjustments made by one node.

Example 7

In FIG. 6, if interference information is provided to L2 through the CSAPL2 interface by D.RRM, L2 should reflect the following in scheduling.

The degree of interference in a particular resource area

Whether the terminal has the ability to cancel interference

-Exclusive Use of Specific Resource Zones Occurs

In scheduling, a weight for interference control may be assigned by a cost function. For example, the resource allocation band selection preference (Weighted_CQI (I, j)) may be defined as in Equation (31) below, and resource allocation scheduling may be performed according to this equation.

Weighted_CQI (i, j) = Weight_1 (i) x [CQI_FBS (j) + Weight_2 (i)] --- Equation (31)

In Equation (31), CQI_FBS (j) represents the CQI value of the j th PRB, Weight_1 (i) represents the band preference weight for the i th terminal, and Weight_2 (i) represents the interference cancellation capability reflectance for the i th terminal. .

At this time, it is possible to set the weight according to each interference characteristic as follows.

That is, since the interference characteristic reflects the possibility of interference or the possibility of canceling interference, it is possible to schedule resource allocation so that interference does not occur.

For example, if there is no interference, it is assumed to be IFZ, and if there is one interference, it is classified as IZ. If the interference is two or more, it is classified as IZ. The IZ may be classified as ICZ if the terminal has the ability to cancel the interference. have. At this time, ICZ can set Off when there is no exclusive use instruction and On when there is an exclusive use instruction. In other words, a cell may have a monopoly or may receive a request for exclusive use of the ICZ from another cell. In addition, HIZ can be set to Off when there is no exclusive use instruction and On when there is an exclusive use instruction. In other words, a cell may have a monopoly or may receive an exclusive use request for the HIZ from another cell.

When the location of the terminal is determined, the always available band and the selective available band are determined according to the location according to the above-described embodiment, and IFZ, LIZ, IZ, etc. are determined based on the allocated band. The ability to determine the ICZ and HIZ for the IZ can be determined, and the exclusive use of the band can be determined by signaling.

Based on this, weight_1 (i) can be regarded as high because it normally assigns the band if IFZ remains, and it can be set as Medimum because there will be LIZ band if there is no IFZ band and there is only LIZ band. On the other hand, even in the case of IZ-ICZ, if the monopoly is granted by my cell, Weight_1 (i) in this case may be determined to be High because the IZ-ICZ band is allocated first to IFZ next to IFZ. Similarly, even in IZ-HIZ, if the monopoly is granted in its cell, Weight_1 (i) can be determined as High.

Weight_2 (i) can define and operate a predefined value considering system optimization only in the case of IZ-ICZ. In case of IZ-ICZ, this weight is set to 0. When calculating the resource allocation band selection preference, it is possible to perform scheduling as shown in Equation (31) together with Weight_1 (i) and Weight_2 (i).

Example 8

When the UE belonging to the serving cell Cell_i moves to neighbor cells Cell_j and Cell_k, it is possible to set RSRP reference values according to the position and direction of the UE and determine the position of the UE according to the RSRP. For example, it may be determined whether the terminal is in the ICU of the Cell_i or triggered by the CEU in the ICU based on the RSRP.

The location of the terminal can be classified as follows.

-D1: ICU area of the serving cell Cell_i

-D2: region adjacent to the adjacent cell Cell_j in the CEU region of the serving cell Cell_i

-D3: region adjacent to the adjacent cell Cell_k in the CEU region of the serving cell Cell_i

-D4: region adjacent to Cell_k while adjacent to Cell_j in the CEU region of the serving cell Cell_i

39 shows pure values of RSRP measured from a terminal. In FIG. 39, M, which are pure values of Cell_i, Cell_j, and Cell_k, may be Layer 1 filtered, and the filtered ML1 value may or may not pass through Layer 3 filtering. In addition, each RSRP of Cell_i, j, k processed at the end of the report to the base station may be reported to the node in a periodic form, or an event according to RSRP reference value Thr1 or Thr2 may be defined and reported to the node.

When the location of the terminal is determined, it is possible to instruct scheduling to use a specific resource at the L2 level or to perform power adjustment at the L1 level according to the above-described resource allocation rule.

Whether the location of the terminal is performed in the terminal or the base station can be used as shown in FIG. 40.

In FIG. 40, the measured values of cells measured at regular time intervals may be processed as shown in FIG. 39. The measured serving cell final measurement value is referred to as Ms (i), and this Ms (i) is defined as Thr1 (that is, RSRP reference). If the value is greater than 1), it should be decided as the D1 region, and if it is less than Thr2 (that is, the RFRP reference value 2), D2, D3, and D4 should be distinguished. And Mn (k), if it is not D1, if | Mn (j) -Mn (k) | is smaller than Thr2, D4 may be determined. Otherwise, D2 may be determined.

Example 9

The reason for defining the interference cancellation characteristic (ICZ) is that the interference cancellation performed in L1 of FIG. 6 is difficult to operate efficiently in the case where interference occurs in a random manner. Therefore, by notifying the L1 of the possibility of interference on a certain frequency resource at the current terminal location, efficient interference cancellation can be performed.

In conclusion, in order to increase interference cancellation efficiency, the artificial control of the characteristics and the possibility of interference is artificially controlled based on the framework of FIG. There is a need for physical channel designs that can facilitate design and enable this operation. As an example, a PRB selected under the assumption that interference cancellation will operate and a PRB selected under the assumption that interference cancellation does not operate may be designed to have different physical channel structures.

In addition, when a specific cell intends to exclusively use a resource corresponding to ICZ, two operations can be considered. The first possible operation is to make the area exclusively used by a particular cell, that is, only that cell uses that ICZ and no other cell uses the ICZ. The second possible operation is to use a specific cell exclusively for the area, but to improve performance by introducing Network MIMO concept. This Newtwork MIMO concept requires a Central Node and the following three points can be considered.

In a method in which one terminal utilizes both the ICZ of the current serving cell and the neighboring cell at the cell boundary, the terminal separates and transmits data using the ICZs of all neighboring cells, thereby improving transmission data throughput using receive diversity. Can be increased.

Soft combining by receive diversity by transmitting a multicast of the same data using the ICZ of all the neighboring cells in a manner in which one UE utilizes both the ICZ of the current serving cell and the neighboring cell at the cell boundary. Inning can increase the SINR at the cell boundary.

Just as central node resource control such as MCE is necessary for MBSFN, control for utilizing ICZ in Central Node is required for ICZ utilization in inter-cell interference coordination.

Example 10

In the above-described embodiments, the cell is divided into a plurality of areas, the resources that are always available and selectively available for each area are designated, the interference characteristics are assigned to each of the designated resources, and then, according to the location and the interference characteristics of the terminal. It relates to various ways to perform resource allocation scheduling and power limitation.

However, if these resources are fixedly used, the resources used by certain areas may be constantly in a bad environment. Therefore, there is a way to rotate the resources (Rotation) to solve this. In other words, there may be a method of turning areas by cell boundaries by constantly turning resources by area according to a rule, and obtaining frequency diversity by exchanging resources allocated to the ICU and resources allocated to the CEU. It may be.

1 illustrates a communication framework according to an embodiment of the present invention.

2 illustrates frequency reuse and cell planning according to an embodiment of the present invention.

3 illustrates frequency reuse and cell planning according to an embodiment of the present invention.

4 illustrates a resource according to an embodiment of the present invention.

5 illustrates a configuration of an interference control apparatus according to an embodiment of the present invention.

6 illustrates an interference control apparatus and a communication framework according to an embodiment of the present invention.

7 illustrates a location of a terminal and an area of a cell according to an embodiment of the present invention.

8 illustrates resource information according to an embodiment of the present invention.

9 illustrates available resource bands for respective regions according to the embodiment 1-1 of the present invention.

10 is a view illustrating available resource bands and interference characteristics for each region according to Example 1-1 of the present invention.

11 shows available resource bands for respective regions according to embodiments 1-2 of the present invention.

12 shows available resource bands and interference characteristics for each region according to embodiments 1-2 of the present invention.

13 illustrates resource information according to an embodiment of the present invention.

14 illustrates available resource bands for respective regions according to embodiments 1-3 of the present invention.

15 illustrates available resource bands and interference characteristics for each region according to embodiments 1-3 of the present invention.

16 illustrates available resource bands for respective regions according to embodiments 1-4 of the present invention.

17 is a view illustrating available resource bands and interference characteristics for each region according to embodiments 1-4 of the present invention.

18 illustrates available resource bands for respective regions according to the exemplary embodiment 1-5 of the present invention.

19 illustrates available resource bands and interference characteristics for respective regions according to the exemplary embodiments 1-5 of the present invention.

20 illustrates resource information according to an embodiment of the present invention.

21 shows available resource bands for respective regions according to embodiments 1-6 of the present invention.

22 is a view illustrating available resource bands and interference characteristics for each region according to embodiments 1-6 of the present invention.

23 illustrates a sectoring and resource allocation scheme according to a second embodiment of the present invention.

24 illustrates resource information according to an embodiment of the present invention.

FIG. 25 is a view illustrating available resource bands and interference characteristics for each region according to Example 3-1 of the present invention. FIG.

26 illustrates resource information according to an embodiment of the present invention.

27 shows available resource bands and interference characteristics for each region according to Embodiment 3-2 of the present invention.

28 shows available resource bands for respective regions according to the embodiment 4-1 of the present invention.

29 shows available resource bands and interference characteristics for each region according to Embodiment 4-1 of the present invention.

30 shows available resource bands for respective regions according to the embodiment 4-2 of the present invention.

31 shows available resource bands and interference characteristics for each region according to Embodiment 4-2 of the present invention.

32 shows available resource bands for respective regions according to the embodiment 4-3 of the present invention.

33 shows available resource bands and interference characteristics for each region according to the embodiment 4-3 of the present invention.

34 shows available resource bands for respective regions according to the embodiment 4-4 of the present invention.

35 is a view illustrating available resource bands and interference characteristics for each region according to embodiments 4-4 of the present invention.

36 illustrates available resource bands for respective regions according to the embodiment 4-5 of the present invention.

37 shows available resource bands and interference characteristics for each region according to the embodiment 4-5 of the present invention.

38 illustrates available resource bands and interference characteristics for each region according to the fifth embodiment of the present invention.

39 is a view illustrating a signal received by a base station for locating a terminal according to an embodiment of the present invention.

40 is a view illustrating a method for locating a terminal according to an embodiment of the present invention.

Claims (19)

An acquisition unit for obtaining information about a resource to be used by the serving cell and the neighbor cell; A determination unit dividing the serving cell into at least one region, designating the resource for each region, and giving an interference characteristic to each resource designated for each region; And An adjusting unit configured to perform resource allocation scheduling or resource power management using the designated resource and the interference characteristic according to the position of the terminal in the serving cell; Inter-cell interference control device comprising a. The method of claim 1, The information on the resource, the inter-cell interference control device, characterized in that it includes the total resources to be used by the serving cell and the neighbor cell, and resources separately defined from the total resources. The method of claim 2, The separately defined resource may include at least one of a prohibited band, a common used band, and a common unused band. The method of claim 1, The information on the resource, the inter-cell interference control device, characterized in that defined for each sector of the cell. The method of claim 1, The region includes a central region and a peripheral region, The resource specified in the peripheral area, the inter-cell interference control device, characterized in that it comprises a resource that is always specified and optionally specified. The method of claim 5, The always specified resource, the inter-cell interference control device, characterized in that using the remaining resources other than the resources defined separately from the total resources of the serving cell. The method of claim 5, And wherein the always specified resource includes a common part of the rest band except the forbidden band of the serving cell and the forbidden band of the neighboring cell. The method of claim 5, The selectively specified resource may include a resource defined by using a resource other than the always specified resource in all resources of the serving cell. The method of claim 5, The selectively designated resource may include a common portion of the forbidden band of the serving cell and the forbidden band of the neighboring cell, a common use portion of the serving cell and the neighboring cell, a common unused portion of the serving cell and the neighboring cell, and And at least one of a portion defined by the serving cell or the neighboring cell for exclusive use. The method of claim 1, The interference characteristic may include a first interference characteristic given to a resource that does not cause interference, a second interference characteristic given to a resource capable of avoiding interference by power adjustment, and possibly a interference occurrence. A third interference characteristic assigned to a resource capable of avoiding interference by canceling physical interference of the fourth interference characteristic, and a fourth interference characteristic conferred to a resource capable of avoiding interference through message exchange with another cell, which is likely to occur. Inter-cell interference control device comprising at least any one of. The method of claim 1, The resource allocation scheduling is performed using weights assigned to each resource, and the weights are set differently according to the interference characteristics. The method of claim 1, The resource power management is performed using a maximum power value assigned to each resource, and the maximum power value is set differently according to the interference characteristics. Obtaining information about a resource to be used in the serving cell and the neighbor cell; Dividing the serving cell into at least one region, assigning the resource for each region, and assigning an interference characteristic to each resource designated for each region; And Performing resource allocation scheduling or resource power management using the designated resource and the interference characteristic according to the location of the terminal in the serving cell; Inter-cell interference control method comprising a. The method of claim 13, The information on the resource, the inter-cell interference control method comprising the total resources to be used by the serving cell and the neighbor cell, and resources separately defined from the total resources. The method of claim 13, The information on the resource is inter-cell interference control method, characterized in that for each sector of the cell. The method of claim 13, The region includes a central region and a peripheral region, The resource specified in the peripheral area, the inter-cell interference control method characterized in that it comprises a resource that is always specified and optionally specified. The method of claim 16, The always-designated resource includes a common part of the rest band except the forbidden band of the serving cell and the forbidden band of the neighboring cell. The method of claim 16, The selectively designated resource may include a resource defined by using a resource other than the always specified resource in all resources of the serving cell. The method of claim 13, The interference characteristic may include a first interference characteristic given to a resource that does not cause interference, a second interference characteristic given to a resource capable of avoiding interference by power adjustment, and possibly a interference occurrence. A third interference characteristic assigned to a resource capable of avoiding interference by canceling physical interference of the fourth interference characteristic, and a fourth interference characteristic conferred to a resource capable of avoiding interference through message exchange with another cell, which is likely to occur. Inter-cell interference control method comprising at least any one of.

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