KR20120106436A - Scheduling apparatus and method - Google Patents

Abstract

PURPOSE: A scheduling apparatus and a method thereof are provided to perform handover to macro cells of difference frequency in case a socket service request is transmitted from a terminal in a femto cell. CONSTITUTION: A service request receiving unit(111) receives a service request from a terminal. The terminal is connected to a femto cell. A determining unit(112) determines whether the service request is a circuit service request or a packet data service request. A handover controlling unit(113) controls handover of the terminal to a target macro cell in case the service request is the circuit service request. [Reference numerals] (111) Service request receiving unit; (112) Determining unit; (114) Message transmitting unit; (115) Message receiving unit; (116) Determining unit; (117) Handover indicating unit; (118) Estimating unit; (119) Selecting unit; (120) Terminal; (AA) Handover controlling unit

Description

Scheduling Apparatus and Method {SCHEDULING APPARATUS AND METHOD}

A scheduling apparatus and method are disclosed. In particular, embodiments of the present invention, when a circuit service request such as a voice or video call is transmitted from a terminal connected to a femtocell, the terminal uses a macrocell of another frequency having a relatively large cell radius. The present invention relates to a technique capable of providing a high speed data service to other users accessing a femtocell while providing a stable voice or video service to the terminal.

As mobile communication has evolved from providing voice communication services to simple mobile users to providing various multimedia services, more bandwidth is required in a mobile environment.

Accordingly, the introduction of ultra-small base stations that can improve the data transmission rate by increasing the frequency reuse rate as a solution to the increase in data usage in recent years.

There is increasing interest in femtocells with respect to the introduction of such micro base stations.

Femtocell is a communication technology that allows users to freely use wired and wireless communication services through a mobile communication terminal using a micro base station connected to an indoor wired IP network.It does not use an indoor repeater, but directly transmits mobile communication data from a base station to an exchange. As a result, service providers can catch three rabbits simultaneously, such as reducing network construction costs, reducing frequency loads, and improving call quality.In addition, users can use voice and data communication services at a low cost indoors with base stations installed. It is attracting attention as a communication technology.

By installing femtocells dedicated to packet data services in hot spot areas where data usage is high, it is possible to reliably provide high-speed data services to general subscribers.

However, since a handover occurs frequently in a small cell in which users are frequently moved, the quality of the voice or video service may be degraded.

Therefore, in a femtocell environment, it is possible to maintain high-speed data service by minimizing the resources of radio resources allocated to voice or video calls, and to reduce the call quality due to handover in places where the service area is relatively small and the user's movement is frequent. There is a need for research on techniques that can provide high quality services.

According to embodiments of the present invention, when a circuit service request such as a voice or video call is transmitted from a terminal connected to a femtocell, the terminal is handed over to a macrocell of another frequency having a relatively large cell radius, thereby providing stable voice for the terminal. In addition, while providing a video service, it is possible to provide a high-speed data service to other users connected to the femtocell.

According to an embodiment of the present invention, a scheduling apparatus includes a service request receiving unit receiving a service request from a terminal accessing a femtocell, a determining unit determining whether the service request is a circuit service request or a packet data service request, and the service request In the case of a circuit service request, a handover control unit for controlling a handover of the terminal to a target macrocell adjacent to the femtocell.

In this case, according to an embodiment of the present invention, the handover controller is a message transmitter for transmitting a measurement control message including information on at least one cell adjacent to the femtocell, the at least one from the terminal A message receiver for receiving a measurement report message including signal transmission quality information for a cell, a determination unit for determining the target macrocell among the at least one cell based on the signal transmission quality information included in the measurement report message; The terminal may include a handover instruction unit for transmitting a handover instruction message to the target macrocell.

In addition, according to an embodiment of the present invention, the signal transmission quality information for the at least one cell is any one of Received Signal Code Power (RSCP) or Chip Energy / Others Interference (Ec / Io) for the at least one cell. It may include one or more.

In addition, according to an embodiment of the present invention, the determining unit may determine a macro cell of which at least one of the RSCP or the Ec / Io is the maximum among the at least one cell as the target macro cell.

According to an embodiment of the present invention, when the measurement control message is received from the scheduling apparatus, the terminal transmits the information to the at least one cell based on information on the at least one cell included in the measurement control message. The measurement report message may be transmitted to the scheduling apparatus by measuring a signal transmission quality.

According to an embodiment of the present invention, the handover instruction message includes frequency information and synchronization code information of the target macrocell, and the terminal receives the handover instruction message from the scheduling apparatus, when the handover instruction message is received. The handover may be performed to the target macrocell based on the frequency information and the synchronization code information of the target macrocell included in the over indication message.

According to an embodiment of the present invention, the handover controller is an estimator for estimating a pilot Ec / Io for at least one cell adjacent to the femtocell, and the estimated pilot Ec among the at least one cell. A selection unit for selecting a macrocell having a maximum / Io and a determination unit for determining the selected macrocell as the target macrocell when the pilot Ec / Io of the selected macrocell is larger than a predetermined threshold. have.

According to an embodiment of the present invention, when the femtocell belongs to the coverage of one macrocell, the handover controller determines the macrocell as the target macrocell and hands the terminal to the target macrocell. Over can be controlled.

According to an embodiment of the present invention, a scheduling method includes receiving a service request from a terminal accessing a femtocell, determining whether the service request is a circuit service request or a packet data service request, and the service request is a circuit service request In the case of A, the method comprises controlling a handover of the terminal to a target macrocell adjacent to the femtocell.

In this case, according to an embodiment of the present invention, the controlling of the handover of the terminal comprises: transmitting a measurement control message including information on at least one cell adjacent to the femtocell to the terminal; Receiving a measurement report message including signal transmission quality information for at least one cell, and determining the target macrocell among the at least one cell based on the signal transmission quality information included in the measurement report message And transmitting a handover indication message to the target macrocell to the terminal.

In addition, according to an embodiment of the present invention, the signal transmission quality information for the at least one cell may include any one or more of RSCP or Ec / Io for the at least one cell.

In addition, according to an embodiment of the present invention, the determining may determine a macro cell of which at least one of the RSCP or the Ec / Io is the maximum among the at least one cell as the target macro cell.

According to an embodiment of the present invention, the controlling of the handover of the terminal includes estimating a pilot Ec / Io for at least one cell adjacent to the femtocell, and the estimated pilot among the at least one cell. The method may include selecting a macrocell having the maximum Ec / Io and determining the selected macrocell as the target macrocell when the pilot Ec / Io of the selected macrocell is larger than a predetermined threshold.

According to an embodiment of the present invention, the controlling of the handover of the terminal may include determining the macrocell as the target macrocell when the femtocell belongs to the coverage of one macrocell. Can be.

According to embodiments of the present invention, when a circuit service request such as a voice or video call is transmitted from a terminal connected to a femtocell, the terminal is handed over to a macrocell of another frequency having a relatively large cell radius, thereby providing stable voice for the terminal. In addition, while providing a video service, it is possible to provide a high-speed data service to other users connected to the femtocell.

In addition, embodiments of the present invention can provide a faster packet data service at a lower cost than using a conventional mobile communication network for a hot spot area, and can be degraded due to handover that occurs frequently in a small cell. By handing over an existing voice call or video call to a macro cell, it is possible to prevent deterioration of the quality of the voice call or video call.

1 is a diagram showing the structure of a scheduling apparatus according to an embodiment of the present invention.
2 is a flowchart illustrating a scheduling method according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

A femtocell base station is a small base station that provides a mobile communication service to an area within a 10m radius. It is mainly installed in the area where shadow of the macro cell is deteriorated, such as home or inside the building, to be used for the purpose of supplementing the quality of mobile communication service, or installed in the hot spot where the service needs of users are concentrated. Used for the purpose of improving quality.

In addition, the femtocell base station uses a general-purpose Internet line for communication with the core network, which is a core control station of a mobile communication network, and thus has low installation cost and maintenance cost, and can be installed anywhere in the area where the Internet line is installed. have.

Recently, femtocells have been discussed with wireless LANs as the wireless data traffic has increased rapidly. Since femtocells use licensed frequencies, connection speeds are faster and more stable for packet services.

In general, when a femtocell base station dedicated to packet data service is installed in a hot spot area, it is possible to stably provide high speed data service to general subscribers. However, since a handover occurs frequently in a small cell in which users are frequently moved, the quality of voice or video service may be degraded.

Accordingly, embodiments of the present invention, when a circuit service request such as a voice or video call is transmitted from a terminal connected to a femtocell, by handing over the terminal to a macrocell of a different frequency with a relatively large cell radius, In addition to providing a stable voice or video service, it is possible to provide a high-speed data service to other users connected to the femtocell.

1 is a diagram showing the structure of a scheduling apparatus according to an embodiment of the present invention.

Referring to FIG. 1, the scheduling apparatus 110 includes a service request receiver 111, a determiner 112, and a handover controller 113.

The service request receiver 111 receives a service request from the terminal 120 accessing the femtocell.

The determination unit 112 determines whether the service request is a circuit service request or a packet data service request.

When the service request is a circuit service request, the handover control unit 113 controls the terminal 120 to hand over the terminal 120 to a target macrocell adjacent to the femtocell.

In this case, according to an embodiment of the present invention, the handover controller 113 may include a message transmitter 114, a message receiver 115, a determiner 116, and a handover indicator 117.

The message transmitter 114 transmits a measurement control message including information on at least one cell adjacent to the femtocell to the terminal 120.

In this case, when the measurement control message is received from the scheduling apparatus 110, the terminal 120 determines the signal transmission quality of the at least one cell based on the information on the at least one cell included in the measurement control message. The measurement report message may be transmitted to the scheduling apparatus 110.

In this case, the message receiver 115 receives the measurement report message including the signal transmission quality information for the at least one cell from the terminal 120.

The determination unit 116 determines the target macrocell among the at least one cell based on the signal transmission quality information included in the measurement report message.

In this case, according to an embodiment of the present invention, the signal transmission quality information for the at least one cell may include RSCP or Ec / Io for the at least one cell.

In this case, according to an embodiment of the present invention, the determination unit 116 may determine a macro cell of which at least one of the RSCP or the Ec / Io is the maximum among the at least one cell as the target macro cell.

The handover instruction unit 113 transmits a handover instruction message to the target macrocell to the terminal 120.

In this case, according to an embodiment of the present invention, the handover indication message may include frequency information and sync code information of the target macrocell.

In this case, when the handover instruction message is received from the scheduling apparatus 110, the terminal 120 hands the target macrocell to the target macrocell based on the frequency information and the synchronization code information of the target macrocell included in the handover instruction message. You can perform an over.

In this case, according to an embodiment of the present invention, the terminal 120 may maintain a circuit service by performing a hard handover between frequencies to the target macrocell.

According to an embodiment of the present invention, when the femtocell belongs to the coverage of one macrocell, since the target macrocell is one, the handover control unit 113 transmits the measurement control message to the terminal 120. The terminal 120 may control the terminal 120 to perform a blind hard handover to the target macrocell without performing the process of receiving the measurement report message from the terminal 120 or the like.

Through this, embodiments of the present invention can increase the hard handover success rate of the terminal 120 because the terminal 120 can exclude the time for measuring the signal strength of the cell of a different frequency.

According to an embodiment of the present invention, the handover controller 113 may further include an estimator 118 and a selector 119.

The estimator 118 configures the at least one neighbor neighbor list in the femtocell based on the received signal strength indication (RSSI) and the pilot RSCP for the at least one cell measured using a downlink reception function. The pilot Ec / Io for one cell is estimated.

In this case, the estimator 118 may estimate the pilot Ec / Io according to Equation 1 below.

The selector 119 selects a macrocell having the maximum pilot Ec / Io of the at least one cell.

In this case, when the pilot Ec / Io of the selected macrocell is greater than a predetermined threshold, the determination unit 116 may determine the selected macrocell as the target macrocell.

At this time, according to an embodiment of the present invention, the determining unit 116 is larger than the first threshold value, the difference between the pilot Ec / Io of the selected macro cell and the Ec / Io of the other neighboring cells, When the pilot Ec / Io is larger than the predetermined second threshold, the selected macrocell may be determined as the target macrocell.

In other words, when the pilot Ec / Io of the selected macrocell satisfies the following Equation 2 and Equation 3, the determiner 116 may determine the selected macrocell as the target macrocell.

At this time, according to an embodiment of the present invention, the scheduling device 110, if the pilot Ec / Io of the macro cell selected by the selection unit 119 satisfies the equation (2) and the equation (3), the terminal 120 Instead of transmitting the measurement control message or receiving the measurement report message from the terminal 120, the scheduling unit 110 itself determines that the selected macro cell is the target macro cell. By determining, the terminal 120 may control the terminal 120 to perform a blind hard handover to the target macrocell.

 In other words, when there is only one macro cell that satisfies Equation 2 and Equation 3, the scheduling apparatus 110 determines the macro cell as the target macro cell to perform blind hard handover of the terminal 120. Can be controlled.

According to another embodiment of the present invention, the femtocell system operated by the scheduling device 110 is connected to a Serving GPRS Support Node (SGSN) and a Gateway GPRS Support Node (GGSN) through a gateway way (AGW), thereby providing a terminal 120. A femtocell base station which provides voice or video simultaneous services among data services by being connected to a mobile switching center (MSC) and a media gate way (MGW) through the AGW. Can be.

According to an embodiment of the present invention, the scheduling device 110 may be configured as a device included in the femtocell base station or may be configured as a separate stand-alone device for femtocell system operation.

2 is a flowchart illustrating a scheduling method according to an embodiment of the present invention.

In step S210, a service request is received from a terminal accessing a femtocell.

In step S220, it is determined whether the service request is a circuit service request or a packet data service request.

As a result of the determination of step S220 in step S230, if the service request is a packet data service request, a packet data service is provided to the terminal and the process ends.

However, if the service request is a circuit service request as a result of the determination of step S220 in step S230, in step S240, the handover of the terminal is controlled by a target macrocell adjacent to the femtocell. .

At this time, according to an embodiment of the present invention, step S240 may include transmitting a measurement control message including information on at least one cell adjacent to the femtocell to the terminal.

Then, step S240 may further include receiving a measurement report message including the signal transmission quality information for the at least one cell from the terminal.

In this case, when the measurement report message is received from the terminal, in step S240, the method further includes determining the target macrocell among the at least one cell based on the signal transmission quality information included in the measurement report message. can do.

In this case, according to an embodiment of the present invention, the signal transmission quality information for the at least one cell may include RSCP or Ec / Io for the at least one cell.

In this case, according to an embodiment of the present disclosure, the determining of the target macrocell may include determining, as the target macrocell, a macrocell in which at least one of the RSCP and the Ec / Io is the maximum among the at least one cell. have.

Then, the step (S240) may further include transmitting a handover indication message to the target macrocell to the terminal.

In this case, the terminal may perform a handover to the target macrocell based on the handover indication message.

According to an embodiment of the present invention, in step S240, estimating pilot Ec / Io for at least one cell adjacent to the femtocell and macro of the estimated pilot Ec / Io of the at least one cell being the maximum And selecting a cell.

In operation S240, when the pilot Ec / Io of the selected macrocell is larger than a predetermined threshold, the selected macrocell may be determined as the target macrocell.

In addition, according to another embodiment of the present invention, step S240 may include determining the macrocell as the target macrocell when the femtocell belongs to the coverage of one macrocell.

The scheduling method according to an embodiment of the present invention has been described above with reference to FIG. 2. Here, since the scheduling method according to an embodiment of the present invention may correspond to the configuration of the scheduling apparatus 110 described with reference to FIG. 1, a detailed description thereof will be omitted.

Scheduling method according to an embodiment of the present invention is implemented in the form of program instructions that can be executed by various computer means may be recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks, such as floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

In the present invention as described above has been described by the specific embodiments, such as specific components and limited embodiments and drawings, but this is provided to help a more general understanding of the present invention, the present invention is not limited to the above embodiments. For those skilled in the art, various modifications and variations are possible from these descriptions.

Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

110: scheduling device
111: service request receiving unit 112: determination unit
113: handover control unit 114: message transmission unit
115: message receiving unit 116: determining unit
117: handover indicating unit 118: estimating unit
119: selection unit 120: terminal

Claims (14)

A service request receiving unit receiving a service request from a terminal accessing the femtocell;
A determination unit determining whether the service request is a circuit service request or a packet data service request; And
If the service request is a circuit service request, a handover control unit for controlling the handover of the terminal to a target macrocell adjacent to the femtocell
Scheduling apparatus comprising a. The method of claim 1,
The handover control unit
A message transmitter for transmitting a measurement control message including information on at least one cell adjacent to the femtocell to the terminal;
A message receiving unit which receives a measurement report message including signal transmission quality information for the at least one cell from the terminal;
A determination unit which determines the target macrocell among the at least one cell based on the signal transmission quality information included in the measurement report message; And
Handover indicating unit for transmitting a handover indication message to the target macrocell to the terminal
Scheduling apparatus comprising a. The method of claim 2,
Signal transmission quality information for the at least one cell
And at least one of Received Signal Code Power (RSCP) or Chip Energy / Others Interference (Ec / Io) for the at least one cell. The method of claim 3,
The determination unit
And a macro cell of which at least one of the RSCP and the Ec / Io is the maximum among the at least one cell is determined as the target macro cell. The method of claim 2,
The terminal
When the measurement control message is received from the scheduling device, the measurement report is measured to the scheduling device by measuring a signal transmission quality for the at least one cell based on the information on the at least one cell included in the measurement control message. Scheduling device for sending messages. The method of claim 2,
The handover indication message is
Including frequency information and sync code information of the target macrocell,
The terminal, when the handover instruction message is received from the scheduling apparatus, the scheduling apparatus for performing a handover to the target macrocell based on the frequency information and the synchronization code information of the target macrocell included in the handover instruction message. . The method of claim 1,
The handover control unit
An estimator estimating a pilot Ec / Io for at least one cell adjacent to the femtocell;
A selection unit for selecting a macrocell having the maximum estimated pilot Ec / Io among the at least one cell; And
A determination unit for determining the selected macrocell as the target macrocell when a pilot Ec / Io of the selected macrocell is larger than a predetermined threshold
Scheduling apparatus comprising a. The method of claim 1,
The handover control unit
And when the femtocell belongs to the coverage of one macrocell, determining the macrocell as the target macrocell to control handover of the terminal to the target macrocell. Receiving a service request from a terminal accessing the femtocell;
Determining whether the service request is a circuit service request or a packet data service request; And
If the service request is a circuit service request, controlling a handover of the terminal by a target macrocell adjacent to the femtocell
Scheduling method comprising a. 10. The method of claim 9,
Controlling handover of the terminal
Transmitting a measurement control message including information on at least one cell adjacent to the femtocell to the terminal;
Receiving a measurement report message including signal transmission quality information for the at least one cell from the terminal;
Determining the target macrocell among the at least one cell based on the signal transmission quality information included in the measurement report message; And
Transmitting a handover indication message to the target macrocell to the terminal;
Scheduling method comprising a. The method of claim 10,
Signal transmission quality information for the at least one cell
A scheduling method comprising at least one of Received Signal Code Power (RSCP) or Chip Energy / Others Interference (Ec / Io) for the at least one cell. The method of claim 11,
The step of determining
A scheduling method of determining a macro cell of which at least one of the RSCP and the Ec / Io is the maximum among the at least one cell as the target macro cell. 10. The method of claim 9,
Controlling handover of the terminal
Estimating a pilot Ec / Io for at least one cell adjacent to the femtocell;
Selecting a macrocell having the maximum estimated pilot Ec / Io among the at least one cell; And
If the pilot Ec / Io of the selected macrocell is greater than a predetermined threshold, determining the selected macrocell as the target macrocell
Scheduling method comprising a. 10. The method of claim 9,
Controlling handover of the terminal
If the femtocell belongs to the coverage of one macrocell, determining the macrocell as the target macrocell
Scheduling method comprising a.

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