KR20070023510A - Communication resource allocation method of basestation - Google Patents

Abstract

Disclosed is a communication resource allocation method of a base station for solving a resource request imbalance situation in a cell.

The base station allocates a whisper resource, which is a part of communication resources, to a whisper region, which is an area around the base station in terms of a radio wave environment, and allocates a conversation resource, which is another part of the communication resource, to a conversation area, which is a cell boundary area, in the radio wave environment.

When the resource request of the whispering area increases, the base station further allocates a part of the conversation resource to the whispering area or increases the ratio of the whispering resource. On the other hand, when the resource request of the conversation area increases, the threshold for distinguishing the whisper area from the conversation area is adjusted or the ratio of the conversation resource is increased.

Resource allocation, base station, whisper area, conversation area

Description

COMMUNICATION RESOURCE ALLOCATION METHOD OF BASESTATION

1 is a diagram illustrating a cell to which communication resources are allocated according to an embodiment of the present invention.

2 is a diagram illustrating a cell to which communication resources are allocated according to another embodiment of the present invention.

3 is a diagram illustrating a cell to which communication resources are allocated according to another embodiment of the present invention.

4 is a flowchart illustrating a method of determining a location of a terminal by a base station according to an embodiment of the present invention.

5 is a diagram illustrating a method for determining a location of a terminal by a base station according to another embodiment of the present invention.

6 is a diagram illustrating a method for determining a location of a terminal by a base station according to another embodiment of the present invention.

7 is a diagram illustrating a resource allocation method according to an embodiment of the present invention.

FIG. 8 is a flowchart illustrating a method of allocating a portion of a conversation resource to a terminal of a whisper region to solve an increase in a whisper resource request according to an embodiment of the present invention.

9 is a flowchart illustrating a method of eliminating an increase in a whisper resource request by increasing a ratio of whisper resources according to an embodiment of the present invention.

FIG. 10 is a flowchart illustrating a method of narrowing the range of a conversation resource allocation area to eliminate an increase in a conversation resource request according to an embodiment of the present invention.

FIG. 11 is a flowchart illustrating a method of reducing an increase in a conversation resource allocation area and resolving an increase in a conversation resource request according to another embodiment of the present invention.

12 is a flowchart illustrating a method of resolving an increase in a conversation resource request by increasing a ratio of conversation resources according to an embodiment of the present invention.

13 is a conceptual diagram illustrating a method of creating a new resource zone according to an embodiment of the present invention.

14 is a flowchart illustrating a method of allocating communication resources when there is no resource area to allocate to a whisper area according to an embodiment of the present invention.

15 is a diagram illustrating a method for allocating communication resources in a three-sector multi-cell environment according to an embodiment of the present invention is the same as the method for allocating communication resources in an omni cell environment.

The present invention relates to a communication resource allocation method of a base station.

In a conventional FDMA or TDMA-based cellular system, cells adjacent to each other do not use common resources for interference avoidance, thereby obtaining sufficient signal-to-interference ratio. However, this caused a low frequency reuse efficiency. In the conventional cellular system, the main purpose is to provide a voice service having a constant data rate. Therefore, in order to increase the capacity of the system, it is effective to increase the number of available channels having sufficient signal-to-interference ratio through power control. For this reason, CDMA-based voice systems have been spread, which greatly increases the frequency reuse efficiency. The CDMA-based voice system reduces the fluctuation in the amount of interference received by each channel through interference averaging so that many channels as a whole receive moderate interference.

However, as the direction of the communication service is changed from a voice service of a constant data rate to a packet service having a variable data rate, it is not necessarily optimal to maintain proper interference through interference averaging. In addition, as orthogonal frequency division multiplexing (OFDM) and orthogonal frequency division multiplexing access (OFDMA) techniques, which are easy to avoid interference, have developed into the cellular domain, interference problems between adjacent cells have reoccurred. .

In order to solve the interference problem between adjacent cells in an OFDM / OFDMA-based cellular environment, there is a method of averaging interference through frequency hopping. According to this method, each base station averages interference between adjacent cells by using a different hopping pattern for each cell.

Another method of averaging interference through frequency hopping to solve the neighbor cell interference problem in an OFDM / OFDMA-based cellular environment is disclosed in Korean Patent Application Laid-Open No. 2005-0048261 ("Orthogonal Frequency Division Multiple Access Based Cellular"). Resource Space Partitioning, Physical Channel Allocation and Power Allocation Method, and Frequency Reuse Efficiency Enhancement Method ", ETRI, 2005.5.24. According to one embodiment of this method, the entire cell is divided into three frequency reuse patterns, and one resource space is divided into three resource subspaces. Each cell causes the terminal to communicate with a large power using one resource subspace among three resource subspaces, and the terminal uses the remaining two resource subspaces among the three resource subspaces to affect adjacent cells. In order not to give a large amount of power, communication is performed with a small power. That is, when a terminal having a poor channel state at a cell boundary communicates with a frequency reuse factor of 3 using one third of all resources, a terminal having a good channel state around a base station communicates without causing significant interference to an adjacent cell. To perform.

Siemens contributed to the 3GPP conference as a way to increase the frequency reuse factor for terminals at cell boundaries (R1-050599, Siemens, "Interference mitigation ?? considerations and results on frequency reuse," 3GPP RAN WG1 Ad Hoc on LTE, Sophia Antipolis, France, June 2005.). According to this method, a terminal in a cell uses a part of resources in common, and a terminal at a cell boundary divides the remaining resources into three equal parts and uses one of them. However, this method is not very good in terms of resource utilization efficiency.

In particular, according to the aforementioned communication resource allocation method of the base station, since the base station continuously allocates a certain portion of the communication resources to the terminal, the terminal has a loss in terms of diversity gain. In addition, the aforementioned communication resource allocation methods of the base station did not provide a solution for the resource request imbalance situation in the cell.

An object of the present invention is to provide a method for allocating a communication resource of a base station to maximize diversity gain and solve a resource request imbalance situation in a cell.

According to an aspect of the present invention, there is provided a communication resource allocation method, the method comprising: allocating a whisper resource whose resource area changes within the communication resource over time to a whisper area that is a peripheral area of the first base station; Allocating a resource corresponding to a whisper resource of the second base station to a conversation area belonging to the base station and bordering with the second base station.

According to another aspect of the present invention, there is provided a method of allocating a whisper resource, which is part of the communication resource, to a whisper area, which is a peripheral area of the first base station, and a boundary between a second base station and a second base station. Allocating a conversation resource corresponding to a whisper resource of the second base station to a conversation area, which is an area; and when a requested resource of the whisper area is larger than a whisper resource allocated to the whisper area, a part of the conversation resource is allocated to the whisper area. Further assigning to.

According to still another aspect of the present invention, there is provided a method for allocating a whisper resource, which is part of the communication resource, to a whisper area, which is a peripheral area of the first base station. Allocating a conversation resource corresponding to a whisper resource of the second base station to a conversation area, which is a boundary area, and increasing a ratio of the whisper resources allocated to the whisper area when a resource request of the whisper area increases. do.

A communication resource allocation method according to another embodiment of the present invention obtains a path attenuation difference value that is a difference between a first path attenuation value from a first base station to the terminal and a second path attenuation value from a second base station to the terminal. Allocating a first resource that is a part of the communication resource to a whisper region in which the path attenuation difference value is greater than a predetermined threshold, and in the conversation area in which the path attenuation difference value is smaller than the threshold value. And allocating a second resource corresponding to a whisper resource of the second base station, and decreasing the threshold value when the resource request of the conversation area increases.

A communication resource allocation method according to another embodiment of the present invention is a first path attenuation difference which is a difference between a first path attenuation value from the first base station to the terminal and a second path attenuation value from the second base station to the terminal. Obtaining a value; obtaining a second path attenuation difference value that is a difference between the first path attenuation value and a third path attenuation value from a third base station to the terminal; Obtaining a third path attenuation difference value that is a difference of a third path attenuation value, and a whisper region wherein the first path attenuation difference value is greater than a first threshold value and the second path attenuation difference value is greater than a second threshold value Allocating a first resource that is a part of the communication resource to the first conversation area, wherein the first path attenuation difference is less than the first threshold and the third path attenuation difference is greater than a third threshold. Allocating a first conversation resource corresponding to a whisper resource of the second base station, and wherein the second path attenuation difference value is smaller than the second threshold value and the third path attenuation difference value is smaller than a third threshold value. Allocating a second conversation resource corresponding to a whisper resource of the third base station in a second conversation area.

According to still another aspect of the present invention, there is provided a method for allocating a whisper resource, which is part of the communication resource, to a whisper area, which is a peripheral area of the first base station. Allocating a first conversation resource corresponding to a whisper resource of the second base station to a conversation area which is a boundary area, and when the resource request of the conversation area increases, the second conversation resource corresponding to the whisper resource of the third base station is allocated. Decreasing the ratio and increasing the ratio of the first conversation resource by a decrease in the ratio of the second conversation resource.

In accordance with still another aspect of the present invention, there is provided a method for allocating a communication resource, by the first base station, receiving path attenuation information from one or more base stations to a terminal, determining an adjacent base station through the path attenuation information; Obtaining a path attenuation difference value, which is a difference between path attenuation information from the first base station to the terminal and path attenuation information from the neighbor base station to the terminal, and a first corresponding to a whisper resource of the neighbor base station among the communication resources; Allocating a resource to a conversation area in which the path attenuation difference value is smaller than the threshold value, and when there is no resource other than the whisper resource of the neighboring base station in the communication resource, the communication resource corresponding to the whispering resource of two or more neighboring base stations. Gathering a portion to form a second resource, and the path attenuation difference Allocating the second resource to a whisper region whose value is greater than the threshold.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

In addition, when a part is said to "include" a certain component, which means that it may further include other components, except to exclude other components unless otherwise stated.

Hereinafter, a frequency, a time, a code, etc. used by a terminal to communicate with a base station will be referred to as a communication resource. In view of the propagation environment, the area around the base station is called a whisper area, and the area of the cell boundary is called a conversation area. A method of distinguishing the whisper region from the conversation region will be described later. In addition, a resource allocated to the whisper region by the base station will be referred to as a whisper resource, and a resource allocated to the conversation region will be referred to as a conversation resource. Whisper resources and conversation resources are part of communication resources.

The base station assigns a communication resource to a specific area at the same time or either the base station allocates a resource for transmitting data to the terminal of the area and the terminal of the area allocates a resource for transmitting data to the base station. Expression that includes.

Now, a method of allocating communication resources to a cell according to various embodiments of the present disclosure will be described with reference to FIGS. 1 to 3. In FIG. 1 to FIG. 3, the resource region is divided in a geometric position but is actually divided according to a propagation environment including shadows and the like.

1 is a diagram illustrating a cell to which communication resources are allocated according to an embodiment of the present invention.

As shown in FIG. 1, communication resources are divided into seven areas 1 to 7. In FIG. 1, communication resources are continuously equally divided, but do not necessarily need to be divided continuously, nor need to be evenly divided. In FIG. 1, the nth resource allocated to the whisper region by the base station is denoted by Wn, and the nth resource allocated to the conversation region is indicated by Sn.

The first to seventh base stations 11 to 17 are the first resource (1), the second resource (2), the third resource (3), the fourth resource (4), the fifth resource (5), the sixth The resources 6 and the seventh resource 7 are allocated to the terminals of the whisper regions, respectively. Referring to the first base station 11, the first base station 11 allocates the first resource 1 as the whisper resource W1 to the terminal of the whispering area 21, which is a peripheral area of the first base station 11. The second to seventh resources 2 to 7 which are the remaining resources are allocated to the terminal of the conversation area. In particular, the first base station 11 uses the second resource 2 used by the second base station 12 as the whisper resource W2 to the terminal of the conversation area 22 which is a boundary area with the second base station 12. It allocates as conversation resource S2. Similarly, the second base station 12 uses the first resource 1 used by the first base station 11 as the whisper resource W1 to the terminal of the conversation area 23 which is a boundary area with the first base station 11. It allocates as conversation resource S1.

When a communication resource is allocated as described above, a method of wireless communication between a base station and a terminal in uplink and downlink will be described. In the uplink, the terminal of the whispering area 21 is interfered by the terminal using the conversation resource (S1) outside the cell managed by the first base station 11 when communicating with the first base station 11, Since the terminal of the whisper area 21 is located close to the first base station 11, communication is possible. On the other hand, the terminal of the conversation area 22 is interfered by the terminal of the whisper area 24, etc. when communicating with the first base station 11, but is located closer than the terminal of the whisper area 24, the communication is possible.

In the downlink, the base station can transmit data to the terminal of the whisper region 21 at low power, so that the amount of interference to the terminal of the conversation region 23 is not large. In addition, even if the base station transmits data with high power to the terminal of the conversation area 22, the amount of interference given to the terminal using the second resource 2 of the outer cell is not large.

In FIG. 1, communication resources are divided into seven equally and allocated to the terminal. However, if the cell shape becomes indefinite rather than hexagonal, the communication resources may be divided into more than seven and allocated to the terminal.

2 is a diagram illustrating a cell to which communication resources are allocated according to another embodiment of the present invention.

As shown in FIG. 2, communication resources are divided into three areas (1 to 3). In addition, the first base station 11 to the seventh base station 17 is the first resource (1), the second resource (2), the third resource (3), the second resource (2), the third resource (3), respectively , Second resource 2 and third resource 3 are allocated to the terminal of the whisper region.

Referring to the first base station 11, as in FIG. 1, the first base station 11 allocates the first resource 1 to the terminal of the whispering region 31 as the whispering resource W1. The second resource 2 to the third resource 3 are allocated to the terminal as a conversation resource. In particular, the first base station 11 uses the second resource 2 used by the second base station 12 as the whisper resource W2 to the terminal of the conversation area 32 which is a boundary area with the second base station 12. It allocates as conversation resource S2.

3 is a diagram illustrating a cell to which communication resources are allocated according to another embodiment of the present invention.

As shown in FIG. 3, communication resources are divided into four areas 1 to 4. The first to seventh base stations 11 to 17 respectively include a first resource 1, a second resource 2, a third resource 3, a fourth resource 4, a second resource 2, The third resource 3 and the fourth resource 4 are allocated to the terminal of the whisper region.

Referring to the first base station 11, as in FIG. 1, the first base station 11 allocates the first resource 1 as the whisper resource W1 to the terminal of the whisper region 41 and is the remaining resource. The second resource to the fourth resource 4 are allocated to the terminal as a conversation resource. In particular, the first base station 11 uses the second resource 2 used by the second base station 12 as the whisper resource W2 to the terminal of the conversation area 42 which is a boundary area with the second base station 12. It allocates as conversation resource S2.

As shown in Figures 1 to 3, according to an embodiment of the present invention, the base station divides the communication resources into three or more and allocates one of them to the terminals around the base station and allocates the remaining resources to the terminals at the cell boundary. . In particular, the base station allocates a resource used by the neighbor cell as a whisper resource to the terminal in the boundary area with the neighbor cell.

Next, a method of determining whether a base station is located near a base station or at a cell boundary will be described with reference to FIGS. 4 to 6.

4 is a flowchart illustrating a method of determining a location of a terminal by a base station according to an embodiment of the present invention. In order to easily explain the flowchart shown in FIG. 4, reference is made to FIG. 1.

First, the terminal calculates a path attenuation value from the first base station 11 through a pilot signal from the first base station 11 (S101).

Next, the terminal calculates a path attenuation value from the second base station 12 through the pilot signal from the second base station 12 (S102).

Then, the terminal transmits the path attenuation value from the first base station 11 and the path attenuation value from the second base station 12 to the first base station 11 (S103).

Upon receiving the path attenuation value, the first base station 11 obtains a path attenuation difference value that is a difference between the path attenuation information from the first base station 11 and the path attenuation information from the second base station 12 (S104).

When the path attenuation difference is greater than the threshold determined by the system design, the first base station 11 determines that the terminal exists in the whisper region 21 (S105) and allocates a whisper resource to the terminal (S106).

On the other hand, if the path attenuation difference value is smaller than the threshold value, the first base station 11 determines that the terminal exists close to the conversation area 22 (S105), and allocates a conversation resource to the terminal (S107).

In the above, the method of determining whether the first base station 11 exists in the whisper area 21 or the conversation area 22 has been described. However, the terminal may provide the first base station 11 with path attenuation values from a plurality of adjacent base stations 11 to 17, and the first base station 11 that receives the terminal is located at a certain position in the cell. You can clearly see if you do.

5 is a diagram illustrating a method for determining a location of a terminal by a base station according to another embodiment of the present invention.

First, the terminal calculates a path attenuation value from the first base station 11 through the pilot signal from the first base station 11 (S201).

Next, the terminal calculates a path attenuation value from the second base station 12 through the pilot signal from the second base station 12 (S202).

Then, the terminal calculates a path attenuation difference value, which is a difference between the path attenuation information from the first base station 11 and the path attenuation information from the second base station 12 (S203), and calculates it to the first base station 11. It transmits (S204).

When the path attenuation difference is greater than the threshold determined by the system design, the first base station 11 determines that the terminal exists in the whispering area 21 (S205), and allocates a whispering resource to the terminal (S206). .

Meanwhile, when the path attenuation difference value is smaller than the threshold value, the first base station 11 determines that the terminal exists in the conversation area 22 adjacent to the second base station 12 (S205), and allocates a conversation resource to the terminal. (S207).

6 is a diagram illustrating a method for determining a location of a terminal by a base station according to another embodiment of the present invention. According to FIG. 6, the base station determines the position of the terminal by an absolute path attenuation value from the base station to the terminal.

In order to determine the location of the terminal according to FIG. 6, the terminal first calculates a path attenuation value from the first base station 11 through a pilot signal from the first base station 11 (S301).

Next, the terminal transmits the path attenuation value from the first base station 11 to the first base station 11 (S302).

When the path attenuation value is smaller than the threshold determined by the system design, the first base station 11 determines the location of the terminal that has sent the path attenuation value as the whisper region 21 (S303), and allocates the whisper resource to the terminal. (S304).

On the other hand, when the path attenuation value is greater than the threshold value, the first base station 11 determines that the terminal that has sent the path attenuation value exists in the conversation area 22 (S303), and allocates a conversation resource to the terminal (S305).

According to FIG. 6, although the first base station 11 determines the position of the terminal by the path attenuation value from the first base station 11 to the terminal, the position of the terminal is determined by the path attenuation value from the second base station 12 to the terminal. You can also judge. That is, the terminal obtains a path attenuation value from the second base station 12 and transmits it to the first base station, and the first base station 11 whispers the position of the terminal when the received path attenuation value is larger than a predetermined threshold value. Judging by (21). When the received path attenuation value is smaller than a predetermined threshold value, the first base station 11 determines the position of the terminal as the conversation area 22.

4 to 6, according to an embodiment of the present invention, the base station determines the location of the terminal based on the propagation environment in various ways. That is, the base station may determine whether the terminal exists in the whisper region or the conversation region using the path attenuation difference value, or may determine the position of the terminal using the absolute path attenuation value. In addition, the base station may determine the position of the terminal using a plurality of path attenuation values corresponding to the plurality of base stations to the terminal.

Next, a resource allocation method according to various embodiments of the present disclosure will be described with reference to FIGS. 7 to 15.

7 is a diagram illustrating a resource allocation method according to an embodiment of the present invention. In particular, FIG. 7 is a diagram illustrating a resource allocation method in a cell to which resources are allocated as shown in FIG. 3.

That is, the resource area of the whisper resource W1 and the conversation resources S2 to S4 of the first base station 11 changes with time.

According to FIG. 7, the first base station 11 uses the first resource region as the whisper resource W1 from 0 seconds to T seconds, and uses the second resource region as the whisper resource W1 at 2T seconds from T seconds. The third resource region is used as the whisper resource W1 at 2T seconds and 3T seconds, and the fourth resource region is used as the whisper resources W1 at 4T seconds at 3T seconds. The first base station 11 changes the area of the conversation resource as time passes. Since the first base station 11 sequentially allocates the fourth resource region to the whisper region 41 in the first resource region over time, the second base station 12 correspondingly corresponds to the fourth in the first resource region. Resource areas are sequentially assigned to the conversation area 43.

If the first base station 11 uses the whisper resources W1 and the conversation resources S2 to S4 with a fixed allocation method as in T seconds from 0 seconds, the first base station 11 or the terminal is diversity. Diversity Benefits are bound to be limited. That is, the terminal using the whisper resource W1 can obtain the diversity gain only in the first resource region.

However, if a resource allocation method such as that shown in FIG. 7 is used, the first base station 11 and the terminal using the whisper resource W1 are divers in the entire communication resource (that is, the first resource area to the fourth resource area). City gains can be obtained. In addition, the first base station 11 and the terminal using the conversation resources S2 to S4 can obtain a diversity gain in all the communication resources (that is, the first resource area to the fourth resource area).

The following describes how to resolve the imbalance in the degree of resource request between the whisper area and the conversation area. See FIG. 1 for this.

First, when the resource request of the whisper area 21 increases, a method of solving the problem will be described with reference to FIGS. 8 and 9. The increase in resource request refers to a case in which traffic to be transmitted or received is increased. The problem in the case where the resource request of the whisper area 21 increases is when the amount of the requested resource of the whisper area 21 is larger than the whisper resource W1.

The first method that can be used when the amount of the requested resource in the whisper area 21 is larger than the whisper resource W1 is a method of allocating a part of the conversation resource to the terminal of the whisper area 21. This method will be described with reference to FIG.

FIG. 8 is a flowchart illustrating a method of allocating a portion of a conversation resource to a terminal of a whisper region to solve an increase in a whisper resource request according to an embodiment of the present invention.

First, the first base station 11 allocates a whisper resource W1 which is a part of communication resource to the whisper area 21 which is a peripheral area of the first base station 11 (S401), and belongs to the first base station 11, The conversation resource S2 corresponding to the whisper resource of the second base station 12 is allocated to the conversation area 22 which is a boundary area with the second base station 12 (S402). At this time, the first base station 11 divides the cell area into the whisper area 21 and the conversation area 22 according to the radio wave environment information. The first base station 11 may divide the cell area into the whisper area 21 and the conversation area 22 according to FIGS. 4 to 6.

Then, when the first base station 11 determines that the amount of the requested resource of the whisper area 21 is greater than the amount of the first resource 1 (S403), the part of the second resource 2 is whispered (21). ) Is further allocated (S404).

Next, as shown in FIG. 8, the case in which the first base station 11 further allocates a portion of the conversation resource to the whisper region 21 will be described by dividing the downlink and the uplink. Referring to the downlink, when the first base station 11 has a lot of data to transmit in the whisper area 21, the first base station 11 uses a portion of the second resource 2 to the terminal of the whisper area 21. Send data to Originally, since the first base station 11 uses the second resource as power that can be transmitted to the entire cell in the downlink, the conversation resource S2 is used for the terminal of the whispering area 21 closer than the conversation area 22. Sending data does not cause problems. In addition, in the uplink, transmission of data to the first base station 11 by the terminal of the whispering area 21 using the conversation resource S2 is an external cell of the cell managed by the first base station 11. It does not cause problems because it reduces the interference to.

A second method that can be used when the amount of the requested resource in the whisper area 21 is larger than the whisper resource W1 is a method of increasing the ratio of the whisper resource W1. This method will be described with reference to FIG.

9 is a flowchart illustrating a method of eliminating an increase in a whisper resource request by increasing a ratio of whisper resources according to an embodiment of the present invention.

First, the first base station 11 allocates a whisper resource W1 which is a part of the communication resource to the whisper area 21 (S501), and the conversation corresponding to the whisper resource of the second base station 12 in the conversation area 22. The resource S2 is allocated (S502).

Then, when the first base station 11 determines that the amount of the requested resource in the whisper area 21 is greater than the amount of the first resource 1 (S503), the ratio of the first resource 1 which is the whisper resource is increased. (S504).

Since the amount of communication resources that can be allocated by the first base station 11 is limited, the first base station 11 decreases the ratio of other resources by increasing the ratio of the first resource 1 which is a whisper resource (S505). . For example, when the first base station 11 determines that the amount of resource requests in the conversation area 22 is less than the amount of the second resource 2, the ratio of the second resource 2 is reduced. The first base station 11 may reduce the ratio of any one of the second resource 2 to the seventh resource 7 to secure an increase of the first resource 1 which is a whisper resource, and the second resource 2 It is also possible to reduce the ratio of two or more of the seventh resource (7) to the seventh resource (7) to secure an increase of the first resource (1) as a whisper resource.

Assuming that the first base station 11 equally uses 1/7 of communication resources, the first base station 11 whispers when the amount of the requested resource of the whisper area 21 is larger than the whisper resource W1. The ratio of the resource W1 is increased by 1/14, and the ratio of the conversation resource S2 is decreased by 1/14. Increasing the ratio of whisper resources W1 and decreasing the ratio of conversation resources S2 does not increase interference to foreign cells, so that the first base station 11 using the method as shown in FIG. 9 does not cause a problem. Do not.

Next, a method of solving the case where the amount of the requested resource in the conversation area 22 is larger than the conversation resource S2 will be described with reference to FIGS. 10 to 12.

FIG. 10 is a flowchart illustrating a method for reducing an increase in conversation resource request by narrowing a range of a conversation resource allocation area according to an embodiment of the present invention. Reference is made to FIG. 1 to describe FIG. 10.

First, the first base station 11 obtains a path attenuation difference value that is a difference between a path attenuation value from the first base station 11 to the terminal and a path attenuation value from the second base station 12 to the terminal (S601).

Next, the first base station 11 performs allocation of communication resources for the area to be managed (S602). That is, the first base station 11 allocates the first resource 1 to the whisper region 21 where the path attenuation difference value is larger than the predetermined threshold value. The first base station 11 allocates a second resource 2 which is a resource used by the second base station 12 as a whisper resource to the conversation area 22 having a path attenuation difference smaller than a predetermined threshold.

Then, when the first base station 11 determines that the amount of the requested resource in the conversation area 22 is greater than the amount of the second resource 2 (S603), the threshold value is reduced (S604). This narrows the regional range of the dialogue area 22 and widens the regional range of the whisper area 21. In this case, since some terminals existing in the conversation area 22 are incorporated into the whisper area 21, the requested resource of the conversation area 22 is reduced by that amount.

Some processing may be required for terminals incorporated into the whisper area 21 in the conversation area 22.

In the case of the downlink, the first base station 11 needs to perform adaptive modulation encoding for the terminal incorporated in the whisper region 21 in the conversation region 22 (S605). The first base station 11 applies a power lower than that applied to the talk resource for the whisper resource in the downlink. However, the terminal incorporated into the whisper region 21 in the conversation area 22 according to the decrease in the threshold value is in a position where the path attenuation from the first base station 11 is large, thereby increasing the probability of an error occurring when receiving data. In this case, when the first base station 11 applies higher power to the whisper resource than before, there is a problem that more interference is caused to the neighboring cell. Accordingly, the first base station 11 performs Adaptive Modulation and Coding (AMC) for the terminal incorporated into the whisper region 21 from the conversation region 22 as the threshold value decreases. That is, the first base station 11 changes the modulation method or encoding method applied to the terminal incorporated into the whisper area 21 from the conversation area 22 according to the threshold value reduction, and transmits the data to the corresponding terminal. Lower. For example, if the first base station 11 transmits data to the terminal through 64-QAM (Quadrature Amplitude Modulation) before the threshold decreases, the first base station 11 is incorporated into the whisper region 21 from the conversation area 22 after the threshold decreases. Data is transmitted via 16-QAM, which is a modulation method with lower error rate than 64-QAM.

In the case of the uplink, the first base station 11 controls the terminal to reduce the transmission power of the terminal incorporated in the talk area 22 to the whisper area 21 (S606), or provides threshold reduction information to the neighboring base stations. It is necessary (S607). The terminal incorporated into the whisper area 21 in the conversation area 22 uses the whisper resources when communicating with the first base station 11, but is not located in the vicinity of the first base station 11 and is in a boundary area with an adjacent cell. Located in Therefore, when the terminal incorporated into the whisper area 21 in the conversation area 22 communicates with the first base station 11 through the whisper resource, a problem occurs that interferes with an adjacent cell. In order to solve this problem, the first base station 11 controls the terminal to reduce the transmission power of the terminal incorporated in the whisper region 21 in the conversation region 22 (S606). Alternatively, the first base station 11 provides the threshold reduction information to the neighboring base station (S607) so that the neighboring base station can use the adaptive modulation encoding by using the threshold reduction information of the first base station 11.

FIG. 11 is a flowchart illustrating a method of reducing an increase in a conversation resource allocation area and resolving an increase in a conversation resource request according to another embodiment of the present invention. Reference is made to FIG. 1 to describe FIG. 11.

The method shown in FIG. 11 incorporates some terminals of the conversation area 22 into the conversation area 25 when the amount of the requested resource in the conversation area 22 is greater than the second resource 2. It is about reducing the amount of resources required.

First, the first base station 11 obtains a first path attenuation difference value C1 which is a difference between path attenuation information from the first base station 11 to the terminal and path attenuation information from the second base station 12 to the terminal. do. The first base station 11 obtains a second path attenuation difference value (hereinafter, C2), which is a difference between path attenuation information from the first base station 11 to the terminal and path attenuation information from the third base station 13 to the terminal. do. In addition, the first base station 11 obtains a third path attenuation difference value (hereinafter, C3) which is a difference between path attenuation information from the second base station 12 to the terminal and path attenuation information from the third base station 13 to the terminal. (S701).

Next, the first base station 11 performs allocation of communication resources for the area to be managed (S702). That is, the first base station 11 has a first resource that is a whispering resource in the whispering area 21 where C1 is greater than the first predetermined threshold (hereinafter, referred to as TH1) and C2 is greater than the second predetermined threshold (hereinafter, referred to as TH2). Allocate 1). Then, the first base station 11 allocates the second resource 2, which is the conversation resource, to the conversation area 22 where C1 is smaller than TH1 and C3 is larger than the predetermined third threshold (hereinafter TH3). In addition, the first base station 11 allocates the third resource 3, which is a conversation resource, to the conversation area 25 where C2 is smaller than TH2 and C3 is smaller than TH3.

Then, when the first base station 11 determines that the amount of the requested resource in the talk area 22 is greater than the amount of the second resource 2 (S703), it increases TH3 (S704). The local range of the conversation area 22 is then narrowed, and the local range of the conversation area 25 is widened. In this case, since some terminals using the second resource 2 use the third resource 3, the requested resource of the conversation area 22 is reduced by that amount.

Some processing may be required for the terminal incorporated in the conversation area 22 from the conversation area 22 as shown in FIG. 10.

That is, the terminal incorporated into the conversation area 25 in the conversation area 22 may have a lower success rate of data reception through the third resource 3 than the terminal originally existing in the conversation area 25. Accordingly, the first base station 11 may perform adaptive modulation encoding on the terminal incorporated in the conversation area 22 from the conversation area 22 (S705).

On the other hand, since the terminal incorporated in the conversation area 22 in the conversation area 22 uses the third resource 3 while being in the boundary area with the cell managed by the second base station 12, the second base station 12 is used. It may interfere with the terminal using the third resource (3) in the governing cell. Accordingly, the first base station 11 controls the terminal to reduce the transmission power of the terminal incorporated in the conversation area 22 from the conversation area 22 (S706), or transmits the increase information of TH3 to the second base station 12. By providing the second base station 12 to use the increase information of TH3 for adaptive modulation encoding (S707).

12 is a flowchart illustrating a method of resolving an increase in a conversation resource request by increasing a ratio of a conversation resource according to an embodiment of the present invention. Reference is made to FIG. 1 to describe FIG. 12.

First, the first base station 11 allocates a whisper resource W1 which is a part of the communication resource to the whisper area 21 (S801), and the conversation corresponding to the whisper resource of the second base station 12 in the conversation area 22. The resource S2 is allocated (S802).

Then, when the first base station 11 determines that the amount of the requested resource in the conversation area 22 is greater than the amount of the conversation resource S2 (S803), it is a resource used by the third base station 13 as a whisper resource. The ratio of the conversation resource S3 is decreased (S804), and the ratio of the conversation resource S2 is increased by that amount (S805). At this time, it is preferable that the ratio of the whisper resources W3 of the third base station 13 does not decrease.

Next, the first base station 11 requests the second base station 12 to reflect the rate increase of the second resource 2 in the whisper resource of the second base station 12 (S806).

The following is a description of a case in which base stations of neighboring cells allocate all resource regions to their whisper regions so that a specific base station is not in a resource region to be assigned as a whisper resource. In this case, a method of creating a new resource region and using it as a whisper resource will be described with reference to FIG. 13.

13 is a conceptual diagram illustrating a method of creating a new resource zone according to an embodiment of the present invention.

As illustrated in FIG. 13, communication resources are divided into a first resource region, a second resource region, a third resource region, and a fourth resource region. In this case, when a part of at least two or more resource areas among the first resource area, the second resource area, the third resource area, and the fourth resource area is collected, a new resource area may be created.

When the base station uses the new resource area generated as a whisper resource, a problem overlaps with another resource area. However, even if there is no resource area to be assigned as a whisper resource, the base station may allocate a certain resource to the terminal of the whisper area. Can be.

Next, a method of allocating communication resources when there is no resource region to allocate as a whisper resource will be described with reference to FIGS. 14 and 1.

14 is a flowchart illustrating a method of allocating communication resources when there is no resource region to allocate as a whisper resource according to an embodiment of the present invention.

First, the first base station 11 receives a path attenuation value from one or more base stations to the terminal from the terminal and collects it for a predetermined time (S901).

The first base station 11 determines an adjacent base station (referred to as a second base station of FIG. 1 for convenience of description) through the collected path attenuation values (S902).

Then, the first base station 11 calculates a path attenuation difference value that is a difference between the path attenuation value from the first base station 11 to the terminal and the path attenuation value from the second base station 12 to the terminal (S903).

The first base station 11 allocates the second resource 2 corresponding to the whisper resource of the second base station 12 for the terminal of the conversation area 22 having a path attenuation difference smaller than a predetermined threshold (S904). ). The first base station 11 allocates a resource corresponding to the whisper resource of the neighboring base station for the boundary area with all neighboring base stations determined in step S902.

Next, the first base station 11 allocates resources to all conversation areas in step S904 and determines whether there are remaining resource areas (S905). If so, all or part of the remaining resource areas are allocated to the terminal of the whispering area. (S906). However, if there are no remaining resources, the first base station 11 configures a new resource region as shown in FIG. 13 (S907), and allocates the configured new resource region to the terminal of the whisper region (S908).

In the above, a method of allocating communication resources by a base station in an omni cell environment has been described. However, the method of allocating communication resources by the base station in a three-sector multi-cell environment is also similar to that of the omni cell environment. This will be described with reference to FIG. 15.

15 is a diagram illustrating a method for allocating communication resources in a three-sector multi-cell environment according to an embodiment of the present invention is the same as the method for allocating communication resources in an omni cell environment.

As shown in FIG. 15, one sector has six neighboring sectors, so that the base station can allocate one whisper resource and one or more conversation resources to one sector. That is, one sector of FIG. 15 completely corresponds to one cell of FIG.

The embodiments of the present invention described above are not implemented only through the apparatus and the method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. Implementation may be easily implemented by those skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

According to an embodiment of the present invention, a base station allocates resources whose resource areas change over time to various areas within a cell, so that terminals in the cell can obtain diversity gains in all ranges of communication resources.

In addition, according to an embodiment of the present invention, the base station can solve the imbalance of the degree of resource request between the whisper area and the conversation area.

In addition, according to an embodiment of the present invention, even when there is no resource region to be allocated to the whisper region, the base station may create a new resource region and allocate it to the whisper region.

Claims (20)

In the method for allocating communication resources by the first base station, Allocating a whisper resource in which a resource region changes in the communication resource over time to a whisper region which is a peripheral region of the first base station; And Allocating a resource corresponding to a whisper resource of the second base station to a conversation area belonging to the first base station and a boundary area with a second base station. The method of claim 1, The whisper resource of the second base station varies in a resource zone within the communication resource. In the method for allocating communication resources by the first base station, Allocating a whisper resource that is part of the communication resource to a whisper area that is a peripheral area of the first base station; Allocating a conversation resource corresponding to a whisper resource of the second base station to a conversation area belonging to the first base station and a boundary area with a second base station; Allocating a portion of the conversation resource to the whisper zone if the requested resource of the whisper zone is greater than the whisper resource allocated to the whisper zone. In the method for allocating communication resources by the first base station, Allocating a whisper resource that is part of the communication resource to a whisper area that is a peripheral area of the first base station; Allocating a conversation resource corresponding to a whisper resource of the second base station to a conversation area belonging to the first base station and a boundary area with a second base station; And Increasing the percentage of whisper resources allocated to the whisper zone when the resource request of the whisper zone increases. The method according to any one of claims 1 to 4, Obtaining a path attenuation difference value that is a difference between a first path attenuation value from the first base station to a terminal and a second path attenuation value from the second base station to the terminal; Determining an area to which the terminal belongs as the whisper area when the path attenuation difference is greater than a predetermined threshold; Determining the area to which the terminal belongs as the conversation area when the path attenuation difference value is smaller than the threshold value. The method of claim 5, Obtaining the path attenuation difference value Receiving the first path attenuation value and the second path attenuation value from the terminal; And Calculating the path attenuation difference value that is a difference between the first path attenuation value and the second path attenuation value. The method of claim 5, Obtaining the path attenuation difference value And receiving the path attenuation difference value from the terminal. The method according to any one of claims 1 to 4, Obtaining a path attenuation value from the first base station to a terminal; Determining an area to which the terminal belongs as the whisper area when the path attenuation value is smaller than a predetermined threshold value; Determining the area to which the terminal belongs as the conversation area when the path attenuation value is greater than the threshold value. The method according to any one of claims 1 to 4, Obtaining a path attenuation value from the second base station to the terminal; Determining an area to which the terminal belongs as the whisper area when the path attenuation value is greater than a predetermined threshold value; Determining the area to which the terminal belongs as the conversation area when the path attenuation value is smaller than the threshold value. In the method for allocating communication resources by the first base station, Obtaining a path attenuation difference value that is a difference between a first path attenuation value from a first base station to the terminal and a second path attenuation value from a second base station to the terminal; Allocating a first resource that is part of the communication resource to a whisper region wherein the path attenuation difference value is greater than a predetermined threshold value; Allocating a second resource corresponding to a whispering resource of the second base station among the communication resources in a conversation area in which the path attenuation difference value is smaller than the threshold value; And Decreasing the threshold if the resource request of the conversation area increases. The method of claim 10, And applying a modulation or coding method having an error rate lower than before the threshold reduction to the terminal that has left the conversation area as the threshold is decreased. The method of claim 10, Controlling the terminal to decrease the transmit power of the terminal leaving the conversation area as the threshold is decreased. The method of claim 10, Providing the reduced information of the threshold to the second base station so that the second base station can use the reduced information of the threshold for adaptive modulation encoding. A method for allocating a communication resource to a terminal by a first base station, Obtaining a first path attenuation difference value that is a difference between a first path attenuation value from the first base station to the terminal and a second path attenuation value from a second base station to the terminal; Obtaining a second path attenuation difference value that is a difference between the first path attenuation value and a third path attenuation value from a third base station to the terminal; Obtaining a third path attenuation difference value that is a difference between the second path attenuation value and the third path attenuation value; Allocating a first resource that is part of the communication resource to a whisper region wherein the first path attenuation difference value is greater than a first threshold and the second path attenuation difference value is greater than a second threshold value; Allocating a first talk resource corresponding to a whisper resource of the second base station in a first talk area in which the first path attenuation difference value is smaller than the first threshold and the third path attenuation difference value is greater than a third threshold value. Doing; And Allocating a second conversation resource corresponding to a whisper resource of the third base station in a second conversation area in which the second path attenuation difference value is smaller than the second threshold value and the third path attenuation difference value is smaller than a third threshold value. Method comprising the steps of: The method of claim 14, Increasing the third threshold if the amount of request resources in the first conversation area is greater than the amount of first conversation resources. The method of claim 15, Controlling the terminal to decrease the transmit power of the terminal leaving the first conversation area as the third threshold is increased. The method of claim 15, And providing the third base station with increase information of the third threshold so that the third base station can use the increase information for adaptive modulation encoding. In the method for allocating communication resources by the first base station, Allocating a whisper resource that is part of the communication resource to a whisper area that is a peripheral area of the first base station; Allocating a first conversation resource corresponding to a whisper resource of the second base station to a conversation area belonging to the first base station and bordering with the second base station; Decreasing the ratio of the second conversation resource corresponding to the whisper resource of the third base station when the resource request of the conversation area increases; And Increasing the ratio of the first conversation resource by decreasing the ratio of the second conversation resource. The method of claim 18, Requesting the second base station to reflect the percentage increase of the first talk resource in a whisper resource of the second base station. In the method for allocating communication resources by the first base station, Receiving, by the first base station, path attenuation information from one or more base stations to a terminal; Determining an adjacent base station based on the path attenuation information; Obtaining a path attenuation difference value that is a difference between path attenuation information from the first base station to the terminal and path attenuation information from the neighboring base station to the terminal; Allocating a first resource among the communication resources corresponding to the whispering resource of the neighboring base station to a conversation area in which the path attenuation difference value is smaller than the threshold value; Gathering a part of communication resources corresponding to the whisper resources of two or more neighboring base stations and configuring a second resource when there are no resources except the whisper resources of the neighboring base station in the communication resources; And Allocating the second resource to a whisper region wherein the path attenuation difference is greater than the threshold.

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