KR101102780B1 - Method and Module for Controlling Pattern-Based Interference Management in Network Apparatus - Google Patents

Abstract

The present invention relates to a pattern-based interference management control module and a method thereof in a network device.

In accordance with another aspect of the present invention, there is provided a pattern-based interference management control module in a network device, the pattern receiving unit receiving a pattern sequence from a central node in an upper cell for a lower cell in which the network device is located; A current pattern extraction unit which sequentially extracts a current pattern from the pattern sequence; A station selector which selects and serves a target station from a station in a lower cell where the network device is located if the network device is registered as a service AP in the current pattern; A data accumulator for accumulating service data for the destination station; A pattern request calculation unit for calculating a pattern request by summing service satisfaction for each station for each pattern; And a pattern request transmitter for transmitting the pattern request to a central node in an upper cell where the network device is located.

Centralized control, pattern, interference

Description

Pattern-based Interference Management Control Module in Network Device and Method therefor {Method and Module for Controlling Pattern-Based Interference Management in Network Apparatus}

An embodiment of the present invention relates to a pattern-based interference management control module and a method thereof in a network device. More specifically, in a multi-cell environment that accommodates a large number of network devices that centrally control downlink transmissions and uplink transmissions, a transmission pattern indicating whether each network device can be serviced can be used. It relates to a pattern-based interference management control module and a method in a network device to control the interference.

FIG. 1 is a diagram illustrating a general wireless communication network structure including an access point (AP) and a plurality of terminals (stations). An access point wirelessly connected to a terminal serves to relay data between an external wired and wireless network and the terminal.

The medium (channel) approach of the nodes (AP and terminal) used in the environment of FIG. 1 is implemented according to the IEEE 802.11 standard, and is a basic access method in the medium access control (MAC) layer protocol of IEEE 802.11. Is a Distributed Coordinated Function (DCF). DCF is based on Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA), and the preemption of the medium is made equal to all nodes in the unit cell. The DCF of the MAC layer protocol waits for interframe space, called Distributed Inter-frame Space (DIFS), and uses a random backoff algorithm to equally allocate to multiple nodes using at most one medium.

This fair access to media provides equal channel access opportunities for APs and terminals, which results in severe asymmetry of uplink / downlink transmission capacity in a single cell network consisting of one AP and multiple terminals. In the presence of terminals, there is a problem that the efficiency of transmission capacity can be seriously degraded due to competition for channel acquisition between stations.

One way to solve the above problems is to centrally communicate with the desired station and control the ratio of uplink / downlink traffic. That is, in FIG. 1, when downlink transmission, the AP always preempts the medium by downlink transmitting a data packet to the station using a medium access latency less than the medium access latency of the station.

The AP that preempts the medium in the downlink sets the transmission duration field to the time required for the uplink transmission so that the station can preempt the medium only when it wants to receive the uplink transmission from a station. Other stations that transmit the dummy packet to the destination station and overhear the dummy packet wait for the corresponding transmission duration so that the destination station of the dummy packet can preempt and uplink the channel during the transmission duration.

2 is a diagram schematically illustrating interference that may occur in a multicell environment.

This method has no problem in the case of one AP because the AP centrally manages channel occupancy. However, in the case of a multicell (multicell) environment using multiple APs to accommodate many stations in a small area as shown in FIG. 2, a centralized control is taken to completely manage channel occupation. The problem arises that the large and small interference that can be caused by multiple APs cannot be avoided.

An embodiment of the present invention is caused by a plurality of network devices by using a transmission pattern indicating whether each network device can be serviced in a multicell environment in which a plurality of network devices that centrally control downlink transmission and uplink transmission are accommodated. To control interference.

According to an embodiment of the present invention, a pattern-based interference management control module in a network device, comprising: a pattern receiver for receiving a pattern sequence from a central node in an upper cell for a lower cell in which the network device is located; A current pattern extraction unit which sequentially extracts a current pattern from the pattern sequence; A station selector which selects and serves a target station from a station in a lower cell where the network device is located if the network device is registered as a service AP in the current pattern; A data accumulator for accumulating service data for the destination station; A pattern request calculation unit for calculating a pattern request by summing service satisfaction for each station for each pattern; And a pattern request transmitter for transmitting the pattern request to a central node in an upper cell in which the network device is located.

The station selector may select the destination station in consideration of the average throughput and the current data rate among the stations in the lower cell.

The station selector may select a station having a maximum value of the following equation as the destination station.

[Equation]

U ' _k (R _k (t-1)) * r _kp (t)

Where U ' _k () represents the derivative of the satisfaction function of station k, R _k (t-1) is the average throughput of station k before the current timeslot (up to t-1), and r _kp ( t) is the transmission rate that station k will get in the current pattern p.

The service data may include an average throughput up to now, a cumulative service time rate received in the current pattern, and a cumulative average transmission rate in the current pattern.

The service satisfaction may be calculated in consideration of the satisfaction function of the destination station, the cumulative service time ratio received by the destination station in the current pattern, the cumulative average transmission rate received by the destination station, and the ratio of the entire pattern sequence of the current pattern. have.

The service satisfaction may be calculated by the following equation.

[Equation]

U'_k(R_k(t))*(π_kp(t)*Γ_kp(t)/π_p)D _p =

U ' _k (R _k (t)) * (π _kp (t) * Γ _kp (t) / π _p )

Where _U'k (R _k (t)) represents the derivative of the satisfaction function of station k, R _k (t) is the average throughput of station k to the current timeslot, and π _kp (t) is the station k is the cumulative service time rate in the current pattern p, Γ _kp (t) is the cumulative average transmission rate received by the destination station in the pattern p, π _p is the rate in the pattern sequence of the current pattern p.

The current pattern extracting unit may be operated every time slot, and the pattern request calculating unit and the pattern request transmitting unit may operate every time slot of a predetermined period.

The pattern request may be calculated when the current pattern is the last pattern of the pattern sequence.

The lower cell is located inside the upper cell.

Further, according to another embodiment of the present invention, a pattern-based interference management control module in a network device, comprising: a pattern request receiving unit for receiving a pattern request from an AP in a cell in which the network device is located; A pattern calculator configured to calculate the total request amount for each pattern by summing the request amounts of all APs for each pattern, and calculating a new pattern ratio in consideration of the total request amount for each pattern; A sequence generator for generating a pattern sequence according to the pattern ratio; And a pattern transmitter for transmitting the pattern sequence to all the APs in the cell.

The pattern ratio can be obtained by the following equation.

[Equation]

π ← proj (π + αD), where α is proportional constant

Where π is a pattern ratio vector representing the ratio of each pattern, D is a pattern request vector, and proj operation means converting to percentage.

According to another embodiment of the present invention, there is provided a pattern-based interference management control method in a network device, the method comprising: receiving a pattern sequence from a central node in an upper cell for a lower cell in which the network device is located; Extracting a current pattern sequentially from the pattern sequence; If the network device is registered as a service AP in the current pattern, selecting and serving a destination station from a station in a lower cell where the network device is located; Accumulating service data for the destination station; Calculating a pattern request by summing service satisfaction for each station for each pattern; And transmitting the pattern request to a central node in an upper cell where the network device is located.

According to another embodiment of the present invention, there is provided a pattern-based interference management control method in a network device, the method comprising: receiving a pattern request from an AP in a cell in which the network device is located; Calculating the total request amount for each pattern by summing the pattern request amounts of all APs for each pattern, and calculating a new pattern ratio in consideration of the total request amount for each pattern; Generating a pattern sequence according to the pattern ratio; And transmitting the pattern sequence to all APs in a cell.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same elements as much as possible even though they are shown in different drawings. In describing the embodiments of the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, in describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected to or connected to that other component, but there may be another configuration between each component. It is to be understood that the elements may be "connected", "coupled" or "connected".

3 is a diagram illustrating a pattern-based interference management control module according to a first embodiment of the present invention.

As shown in FIG. 3, the pattern-based interference management control module according to the first embodiment of the present invention includes a pattern receiver 302, a current pattern extractor 303, a station selector 304, a data accumulator 306, The pattern request calculator 308 and the pattern request transmitter 310 are included.

As shown in FIG. 2, a network device used in a pattern-based interference management control module in a network device in an environment in which a plurality of APs 202, 204, 206 and a plurality of stations 208, 210 share a channel is used as an access point. Point (AP), but the base station may also be a network device, the present invention is not limited thereto. In addition, the stations 208 and 210 may be PDAs, notebook computers, and the like, but are not limited thereto.

4 shows a network comprising a central node 402 and APs 404 and 406. In this case, the network area is composed of an upper cell (herein referred to as a macro cell) and a lower cell (here referred to as a microcell) divided into a plurality of areas therein, and the central node 402 is connected to a function of an AP in a lower cell. It may be a kind of AP that is in charge of all the central control functions of the upper cell, or may be a separate device that is only responsible for the central control function of the upper cell. In the present embodiment, a description will be given on the assumption that it is a separate device that performs the central control function in the upper cell. In addition, in the present embodiment, the network apparatus equipped with the pattern-based interference management control module of the present invention will be described based on the AP1 404.

The pattern receiver 302 receives a pattern sequence from the central node 402 in the upper cell where the AP1 404 is located.

The current pattern extractor 303 sequentially extracts the current pattern from the received pattern sequence.

If the AP1 404 is registered as a service AP in the current pattern on the pattern sequence, the station selector 304 selects and serves a target station from the stations 412 and 414 in the lower cell where the AP1 404 is located.

The data accumulator 306 accumulates the service data for the destination station.

The pattern request calculator 308 calculates a pattern request by summing service satisfaction for each station for each pattern.

The pattern request transmitter 310 transmits the pattern request calculated by the pattern request calculator 308 to the central node 402 in the upper cell where the AP1 404 is located.

The present invention avoids interference during downlink between APs in a manner in which APs are determined to be transmitted according to a specific transmission pattern instead of all APs always transmitting in a period in which the AP downlinks to a station in a corresponding cell.

The pattern receiver 302 receives a pattern sequence from the central node 402 in the upper cell covering the area of the AP1 404. The pattern sequence is an ordered sequence of patterns (P1, P2, P3, P1, P2, ...), and can take the form, each pattern means a combination of several APs are turned off or on. That is, if the AP is turned on and the off is turned off, the number of cases of (AP1, AP2) representing a combination of serving stations in the corresponding cell of each of AP1 and AP2 covered by one central node is (on , on), (on, off), and (off, on) may exist.

Each AP stores a type of pattern. That is, for example, information of P1 = (on, on), P2 = (on, off), and P3 = (off, on) is stored. This type of information may be changed when the number of APs is changed. That is, when there are three APs, examples of pattern types include P1 = (on, on, on), P2 = (on, on, off), P3 = (on, off, on), and P4 = (on, off). , off), P5 = (off, on, on), P6 = (off, on, off), and P7 = (off, off, on).

In the case of two APs, the pattern is (on / off, on / of), but in the case of three APs, the pattern is (on / off, on / off, on / off). do.

As described above, several identical patterns may be repeated in one pattern sequence. The reason for dividing into various kinds of patterns is as follows. When station 2 414, which is located near the center of the cell inside of AP1 404, is served, even if AP2 406 of an adjacent cell serves at the same time, the possibility of interference is small. However, when AP1 404 is serving station 1 412 at the edge of the cell, AP2 406 is stationed when AP2 406 in an adjacent cell simultaneously serves station 3 416. There is a greater likelihood of interference at 1 (412). Therefore, when servicing the station 1 412 located at the cell edge, the operation of the AP2 406 of the neighbor cell is turned off, thereby preventing interference from occurring.

Suppose P1 is (on, off), P2 is (off, on), and P3 is (on, on). Each pattern is applied to each timeslot. That is, in the first timeslot, a pattern of (on, off) is applied, so that the AP1 404 is ON and the AP2 406 is OFF. The pattern sequence is simultaneously transmitted from the central node 402 to all APs in the same form, and thus all APs may be synchronized on or off according to the pattern sequence.

The current pattern extractor 303 extracts the current pattern sequentially in each time slot from the received pattern sequence.

If the AP1 404 is registered as a service AP in the current pattern on the pattern sequence, the station selector 304 selects and serves a target station from the stations 412 and 414 in the lower cell where the AP1 404 is located.

For example, when the pattern is "(AP1, AP2) = P1 (on, off)", corresponding to AP1 404 is on. Since AP1 is on in this pattern and is registered as a service AP in the current pattern, AP1 404 selects a target station among stations in the lower cell to serve. Here, the service means that the AP1 404 transmits a packet to the destination station if there is a packet to be downlinked to the destination station.

The station selector 304 may select a method of selecting a target station from the stations in consideration of the average throughput and the current data rate.

That is, in order to select the destination station, Equation 1 is obtained by multiplying the derivative of the satisfying function and the current data rate for all station k in the cell, and selecting the station having the largest value as the destination station as the destination station. do.

U ' _k (R _k (t-1)) * r _kp (t)

Where U ' _k () represents the derivative of the satisfaction function of station k, r _kp (t) is the transmission rate that station k will get in the current pattern p. In addition, R _k (t-1) may be obtained by Equation 2 as the average throughput of the station k up to the current time slot (up to t-1).

R _k (t) ← (1-β ₁ ) * R _k (t-1) + β ₁ * r _kp (t), where β ₁ is a proportionality constant

r _kp (t) is the transmission rate that station k will obtain in the current pattern p. This rate is known by measuring the channel condition to the station before the AP transmits.

The data accumulator 306 calculates the average throughput up to the present for the destination station, the cumulative service time rate received by the destination station in the current pattern, and the cumulative average transmission rate received by the destination station in the current pattern.

The average throughput to date for the destination station is cumulatively calculated by equation (2).

The cumulative service time ratio π _kp (t) received in the current pattern (eg, P1) received by the destination station k is accumulated by Equation 3.

π _kp (t) ← (1-β ₂ ) * π _kp (t-1) + β ₂ , where β ₂ is a proportionality constant

The cumulative average data rate Γ _kp (t) received by the corresponding destination station k in the current pattern (eg, P1) is accumulated by Equation 4.

Γ _kp (t) ← (1-β ₃ ) * Γ _kp (t-1) + β ₃ * r _kp (t), where β ₃ is a proportionality constant

r _kp (t) is the transmission rate that station k will get in the current pattern p

The pattern request calculator 308 calculates a pattern request by summing service satisfaction for each station for each pattern.

If the AP is registered as a service AP in the current pattern on the pattern sequence, the process of selecting and serving a target station from the stations in the AP and accumulating the service data for the target station after the service occurs every time slot, but the AP is moved from the central node. The process of receiving the pattern sequence and the process of calculating the pattern request are performed at regular intervals. For example, when a pattern request is calculated for every 100 timeslots, a pattern request is calculated for every 100 timeslots, the pattern request is transmitted to the central node 402, and the pattern sequence is generated from the central node 402 that receives the pattern request. Can be received.

In other words, the operation of the station selector 304 and the data accumulator 306 is performed every time slot, and the pattern request calculator 308 and the pattern request transmitter 310 operate every time slot in a predetermined period. Meanwhile, the operation of the pattern receiver 302 may also operate for each time slot of a predetermined period.

The equation for summing service satisfaction for each station with respect to one pattern p may be calculated by Equation 5.

Dⁿ _p = U'_k(R_k(t))*(π_kp(t)*Γ_kp(t)/π_p)

D ⁿ _p = U ' _k (R _k (t)) * (π _kp (t) * Γ _kp (t) / π _p )

Where _U'k () represents the derivative of the satisfaction function of station k, R _k (t) is the average throughput of station k to the current timeslot, and π _kp (t) is the current pattern p received by station k The cumulative service time ratio received at (eg, P1), Γ _kp (t) is the cumulative average transmission rate received by the station k, and π _p is the ratio of the entire pattern sequence of the current pattern p (eg, P1). Π _p can be obtained by calculating the ratio of each pattern from the received pattern sequence. For example, if the sequence of patterns is (P1, P2, P1, P2, P3), then (P1: P2: P3 = 40%: 40%: 20%). In addition, D ⁿ _p is the service satisfaction of each station k for the pattern p with respect to the identifier n of the AP.

[U ' _k (R _k (t)) * (π _kp (t) * Γ _kp (t) / π _p )] in Equation 5 calculates the satisfaction for each station k, so D _p is By adding satisfaction to the station, a pattern request for the pattern can be calculated.

Therefore, the pattern request for the entire pattern becomes a pattern request vector as shown in Equation 6 consisting of the pattern requests calculated for all the patterns.

D = (D ₁ , D ₂ , ..., D _p )

That is, when three patterns exist, the form similar to (D1, D2, D3) is shown.

The pattern request transmitter 310 transmits the pattern request calculated by the pattern request calculator 308 to the central node 402 in the upper cell where the AP1 404 is located.

Meanwhile, the central node 402 receives the pattern request vector from all the APs 404 and 406, generates a new pattern sequence, and sends it to each AP. This will be described later.

5 is a diagram illustrating a pattern-based interference management control module according to a second embodiment of the present invention.

As shown in FIG. 5, the pattern-based interference management control module according to the second embodiment of the present invention includes a pattern request receiver 502, a pattern calculator 504, a sequence generator 506, and a pattern transmitter 508. Include.

This embodiment illustrates the operation of the central node 402 used as a network device.

The pattern request receiver 502 receives a pattern request from all APs in the upper cell where the central node 402 is located.

The pattern calculator 504 calculates the total request amount for each pattern by summing the pattern requests received from all APs by the pattern request receiver 502 for each pattern, and calculates the total request amount for each pattern. In consideration of this, a new pattern ratio is calculated.

The sequence generator 506 generates a pattern sequence according to the calculated pattern ratio.

The pattern transmitter 508 transmits the pattern sequence generated by the sequence generator 506 to all APs in the cell.

The pattern request receiver 502 receives (D ¹ ₁ , D ¹ ₂ , D ¹ ₃ ) and AP2 406 the pattern requests received from all APs in the upper cell where the central node 402 is located from the AP1 404. ) And (D ² ₁ , D ² ₂ , D ² ₃ ).

The pattern calculator 504 calculates the total request amount for each pattern by summing the request amounts of all APs for each pattern for the pattern requests received by the pattern request receiver 502 from all APs. That is, by receiving and summing (D ¹ ₁ , D ¹ ₂ , D ¹ ₃ ) and (D ² ₁ , D ² ₂ , D ² ₃ ), the total request amount for each pattern (D ¹ ₁ + D ² ₁ , D ¹⁾ ₂ + D ² ₂ , D ¹ ₃ + D ² ₃ ).

The pattern calculator 504 calculates a new pattern ratio in consideration of the calculated total request amount for each pattern. The pattern ratio calculated here may be calculated by Equation 7.

π ← proj (π + αD), where α is proportional constant

Here, π is a pattern ratio vector representing the ratio of each pattern, and after multiplying the pattern request vector by a constant constant, it is added to the current pattern ratio, and then it is added to the plane of π ₁ + π ₂ + .. + π _n = 100%. Perform a proj operation that projects and converts it to a percentage. For example, if the result of adding the pattern request vector multiplied by a constant constant to the current pattern ratio is (40 + 10%: 40 + 10%: 20 + 20%), proj (40 + 10%: 40 + 10% : 20 + 30%) becomes proj (50%, 50%, 50%), which translates into a percentage of the total (π ₁ : π ₂ : π ₃ ) = (33.3%: 33.3%: 33.3%) .

The sequence generator 506 generates a pattern sequence according to the calculated pattern ratio.

Here, the actual pattern ratio that is generated is not always correctly generated according to the ratio of (π ₁ : π ₂ : π ₃ ). For example, assuming 10 pattern sequences are generated, the ratio of (33.3%: 33.3%: 33.3%) cannot be accurately reflected as a natural number. As a method of generating the ratio of the pattern sequence calculated by the actual natural number, the pattern number is randomly generated by using a random generator that generates three numbers with a probability (33.3%: 33.3%: 33.3%) at every pattern generation. . When the pattern sequence is generated using the random generator as described above, the pattern ratio may not be accurately reflected. However, when the pattern sequence has several tens or hundreds or more, it may reflect the approximately generated pattern ratio. In this way, the pattern sequence may be the same as (P1, P2, P1, P3, P2, P1, P2, P3, P2, P3). Here, the actual pattern ratio generated is (P1: P2: P1) = (3: 4: 3).

The number of pattern sequences is equal to a predetermined period of timeslots for generating the pattern sequences.

The pattern transmitter 508 transmits the pattern sequence generated by the sequence generator 506 to all APs 404 and 406 in the cell.

6 is a flowchart illustrating a pattern-based interference management control method according to a first embodiment of the present invention.

As shown in FIG. 6, the method for controlling pattern-based interference management in the AP 404 or 406 used as the network device according to the first embodiment of the present invention may be performed through the following steps.

First, a pattern sequence is received from the central node 402 in the upper cell for the lower cell in which the network device is located (S602).

When the timeslot occurs (S604), after receiving the pattern sequence, the current pattern is extracted from the pattern sequence (S606).

If it is determined whether the network device AP is registered as a service AP in the current pattern (S608). If the current pattern is not registered as a service AP, it waits for the next timeslot to occur (S604).

If the current pattern is registered as a service AP, the target station is selected and serviced from stations in the lower cell where the network device is located (610).

After selecting and serving the destination station, service data for the destination station is accumulated (S612).

It is checked whether the current pattern is the last pattern on the pattern sequence (S614).

If it is not the last pattern, wait until the next timeslot occurs (S604). If the current pattern is the last pattern in the pattern sequence, a pattern request is calculated by summing service satisfaction for each station with respect to each pattern (S616).

The calculated pattern request is transmitted to the central node 402 in the upper cell where the network device is located (S618).

7 is a flowchart illustrating a pattern-based interference management control method according to a second embodiment of the present invention.

As shown in FIG. 7, the method for controlling pattern-based interference management in the central node 402 used as the network device according to the second embodiment of the present invention may be performed through the following steps.

First, a pattern request is received from the AP 404 and / or 406 in the cell where the central node 402 is located (702).

The total request amount for each pattern is calculated by summing the pattern request amounts of all APs for each pattern (S704). When the total request amount for each pattern is calculated, a new pattern ratio is calculated in consideration of the total request amount for each pattern (S706).

A pattern sequence is generated according to the calculated pattern ratio (S708), and the generated pattern sequence is transmitted to all APs 404 and 406 in the cell (S710).

As described above, according to an embodiment of the present invention, by using a transmission pattern indicating whether each network device can be serviced in a multicell environment in which a plurality of network devices that centrally control downlink transmission and uplink transmission are accommodated. There is an effect of controlling the interference caused by multiple network devices.

In the above description, all elements constituting the embodiments of the present invention are described as being combined or operating in combination, but the present invention is not necessarily limited to the embodiments. That is, all of the components may operate selectively in combination with one or more of them. In addition, although all of the components may be implemented in one independent hardware, each or all of the components may be selectively combined to perform some or all functions combined in one or a plurality of hardware. It may be implemented as a computer program having a. Codes and code segments constituting the computer program may be easily inferred by those skilled in the art. Such a computer program may be stored in a computer readable storage medium and read and executed by a computer, thereby implementing embodiments of the present invention. The storage medium of the computer program may include a magnetic recording medium, an optical recording medium, a carrier wave medium, and the like.

In addition, the terms "comprise", "comprise", or "having" described above mean that the corresponding component may be embedded unless otherwise stated, and thus, other components. It should be construed that it may further include other components rather than to exclude them. All terms, including technical and scientific terms, have the same meanings as commonly understood by one of ordinary skill in the art unless otherwise defined. Terms commonly used, such as terms defined in a dictionary, should be interpreted to coincide with the contextual meaning of the related art, and shall not be construed in an ideal or excessively formal sense unless explicitly defined in the present invention.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

FIG. 1 is a diagram illustrating a general wireless communication network structure including an access point (AP) and a plurality of terminals (stations).

2 is a diagram schematically illustrating interference that may occur in a multicell environment.

3 is a diagram illustrating a pattern-based interference management control module according to a first embodiment of the present invention.

4 shows a network comprising a central node 402 and APs 404 and 406.

5 is a diagram illustrating a pattern-based interference management control module according to a second embodiment of the present invention.

6 is a flowchart illustrating a pattern-based interference management control method according to a first embodiment of the present invention.

7 is a flowchart illustrating a pattern-based interference management control method according to a second embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

102: AP

104: station 1

106: station 2

108: station 3

202 and 404: AP1

204 and 406: AP2

206: AP3

208, 412: Station 1

210, 414: station 2

302: pattern receiving unit

303: current pattern extraction unit

304: station selection unit

306: data accumulation part

308: pattern request calculation unit

310: pattern request transmission unit

402: central node

416: station 3

502: pattern request receiving unit

504: pattern calculation unit

506: sequence generator

508: pattern transmission unit

Claims (17)

In the pattern-based interference management control module in a network device, A pattern receiver configured to receive a pattern sequence in which a pattern representing a combination in which several APs are turned on / off from a central node in a macro cell for a micro cell in which the network device is located; A current pattern extraction unit which sequentially extracts a current pattern from the pattern sequence; A station selecting unit for selecting and serving a target station from stations in a microcell where the network device is located if the network device is registered as a service AP in the current pattern; A data accumulator for accumulating service data for the destination station; A pattern request calculation unit for calculating a pattern request by summing service satisfaction for each station for each pattern; And A pattern request transmitter for transmitting the pattern request to a central node in a macro cell where the network device is located. , &Lt; / RTI & In the pattern sequence, the central node calculates the total request amount for each pattern by summing up the request amounts of all APs for each pattern, multiplies the total request amount for each pattern by a constant constant, and then adds the current pattern ratio to each value. The method generates and transmits a number corresponding to the pattern number by the number of patterns in the new pattern ratio according to the new pattern ratio. Interference management control module, characterized in that it is generated using a random generator for generating each of the numbers. The method of claim 1, And the station selector selects the destination station in consideration of the average throughput and the current data rate among the stations in the micro cell. The method of claim 1, And the station selector selects a station having a maximum value as the following station as the destination station. [Equation] U ' _k (R _k (t-1)) * r _kp (t) Where U ' _k () represents the derivative of the satisfaction function of station k, R _k (t-1) is the average throughput of station k before the current timeslot (up to t-1), and r _kp ( t) is the transmission rate that station k will get in the current pattern p. The method of claim 1, And the service data includes an average throughput up to now, a cumulative service time rate received in the current pattern, and a cumulative average transmission rate in the current pattern. The method of claim 1, The service satisfaction is An interference function calculated by considering a satisfaction function of the destination station, a cumulative service time rate of the destination station serviced in the current pattern, a cumulative average transmission rate received by the destination station, and a ratio of the entire pattern sequence of the current pattern Management control module. The method of claim 1, The service satisfaction is interference management control module, characterized in that calculated by the following equation. [Equation] D _p =

U ' _k (R _k (t)) * (π _kp (t) * Γ _kp (t) / π _p ) Where _U'k (R _k (t)) represents the derivative of the satisfaction function of station k, R _k (t) is the average throughput of station k to the current timeslot, and π _kp (t) is the station k is the cumulative service time rate in the current pattern p, Γ _kp (t) is the cumulative average transmission rate received by the station k in the pattern p, and π _p is the ratio in the pattern sequence of the current pattern p. The method of claim 1, The operation of the current pattern extractor is performed every time slot, and the pattern request calculator and the pattern request transmitter are operated for each time slot of a predetermined period. The method of claim 1, And the calculation of the pattern request is performed when the current pattern is the last pattern of the pattern sequence. delete In the pattern-based interference management control module in a network device, A pattern request receiver configured to receive a pattern request, which is a request for a pattern representing a combination in which the AP is on / off, from an AP in a cell in which the network device is located; Calculate the total request amount for each pattern by summing the request amounts of all APs for each pattern, multiplying the total request amount for each pattern by a certain constant, and converting the percentage of each pattern to the value added to the current pattern ratio. A pattern calculator for calculating a new pattern ratio; A sequence generator for generating a pattern sequence by using a random generator for generating the number corresponding to the pattern number as many as the number of patterns in the new pattern ratio according to the new pattern ratio, the probability of the new pattern ratio ; And A pattern transmitter for transmitting the pattern sequence to all APs in a cell Interference management control module comprising a. delete In the method comprising a pattern receiver, a current pattern extractor, a station selector, a data accumulator, a pattern request calculator, and a pattern request transmitter, the pattern-based interference management, Receiving, by the pattern receiving unit, a pattern sequence in which a pattern representing a combination in which several APs are turned on / off from a central node in a macro cell for a micro cell in which a network device is located; Extracting the current pattern sequentially from the pattern sequence by the current pattern extracting unit; Selecting, by the station selecting unit, a destination station from among stations in a microcell in which the network device is located if the network device is registered as a service AP in the current pattern; Accumulating the service data for the destination station by the data accumulator; Calculating, by the pattern request calculator, a pattern request by summing service satisfaction for each station with respect to each pattern; And Transmitting, by the pattern request transmitter, the pattern request to a central node in a macro cell where the network device is located; , &Lt; / RTI & In the pattern sequence, the central node calculates the total request amount for each pattern by summing up the request amounts of all APs for each pattern, multiplies the total request amount for each pattern by a constant constant, and then adds the current pattern ratio to each value. The method generates and transmits a number corresponding to the pattern number by the number of patterns in the new pattern ratio according to the new pattern ratio. Interference management control method characterized in that it was generated using a random generator for generating each of the numbers. The method of claim 12, And selecting the destination station in consideration of an average throughput and a current data rate among the stations in the micro cell. The method of claim 12, And the service data includes an average throughput up to now, a cumulative service time ratio received in the current pattern, and a cumulative average transmission rate in the current pattern. The method of claim 12, And extracting the current pattern every time slot, and calculating the pattern request every time slot of a predetermined period. The method of claim 12, And calculating the pattern request when the current pattern is the last pattern of the pattern sequence. A method for controlling a pattern based interference management by an apparatus including a pattern request receiver, a pattern calculator, a sequence generator, and a pattern transmitter, Receiving, by the pattern request receiving unit, a pattern request that is a request for a pattern indicating a combination in which the AP is on / off from an AP in a cell in which a network device is located; The pattern calculator calculates the total request amount for each pattern by summing the request amounts of all APs for each pattern, multiplies the total request amount for each pattern by a certain constant, and then calculates a percentage of each pattern for a value added to the current pattern ratio. Calculating a new pattern ratio by a conversion method; The sequence generator generates a pattern sequence using a random generator that generates a number corresponding to the pattern number by the number of patterns within the new pattern ratio according to the new pattern ratio, but generates each of the numbers with a probability of the new pattern ratio. Doing; And Transmitting, by the pattern transmitter, the pattern sequence to all APs in a cell Interference management control method comprising a.

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