KR101072768B1 - Asynchronous Mobile Communication System and Roaming Control Method - Google Patents

Abstract

An asynchronous mobile communication system and a roaming control method in the system for facilitating network connection of a roaming terminal are provided.

The asynchronous mobile communication system of the present invention is connected to a wireless network controller, is connected to a mobile communication terminal using a plurality of channels, and at least one roaming channel for transmitting a control signal with a power strength greater than other channels of the plurality of channels In the roaming control method of the present invention, the roaming control method of the present invention searches for a roamable communication network and connects to a roaming cell using a roaming channel of the inducing node B, thereby performing location registration for the mobile communication terminal. And instructing the handover node B to handover the mobile communication terminal according to the service request of the mobile communication terminal, and performing the handover by the mobile communication terminal.

According to the present invention, roaming of a mobile communication terminal can be performed quickly.

Roaming, induction, control channels

Description

Asynchronous Mobile Communication System and Roaming Control Method in the System

1 is a block diagram of an asynchronous mobile communication system according to the present invention;

2 is a view for explaining a concept of roaming control in an asynchronous mobile communication system according to the present invention;

3 is a flowchart illustrating a roaming control method in an asynchronous mobile communication system according to the present invention.

Description of the Related Art [0002]

12, 14, 16: Node B 18: Induction Node B

22, 24: wireless network controller 26: switchboard

30: core network 100: roaming mobile communication terminal

The present invention relates to a mobile communication system, and more particularly, to an asynchronous mobile communication system and a roaming control method in the system to facilitate roaming terminal network connection.

In mobile telecommunications, roaming service allows subscribers to use mobile telecommunications service anywhere, across regions or borders. In particular, international roaming is based on agreements between mobile telecommunications providers. Means to use the mobile communication service.

The asynchronous mobile communication system is developed in consideration of an international roaming service, and a roaming service in an asynchronous mobile communication system may be divided into roaming through a mobile communication terminal and roaming through a subscriber identification card (for example, a SIM card). Roaming services through subscriber identity cards offer the advantage of enabling the use of communication services between mobile networks with different radio access schemes, thus providing interoperability between a wider range of systems employing different radio communication technologies. Instead of carrying a mobile communication terminal, a subscriber can access a desired mobile communication network by simply carrying a subscriber identification card and inserting it into another mobile communication terminal. In particular, roaming by the subscriber identity card does not depend on the access system used by each mobile communication network, so there is an advantage that the connection to any communication network does not suffer from technical obstacles.

On the other hand, for the international roaming service, as described above, an agreement between mobile carriers between countries is required.In case a one-to-one agreement is made between the home network operator and the roaming network operator, the subscriber's terminal entering the roaming network is the communication network of the contracted party. In case of agreement on a one-to-many basis, one of a plurality of communication networks should be selected and connected.

To this end, any one of a method of selecting and accessing a communication network to roam manually by a subscriber and a method of automatically accessing a communication network to roam from a mobile communication terminal are used. The home roaming network information and roamable communication network information are recorded on the roamable mobile communication terminal or subscriber identification card. When using the manual access method, a communication network accessible to the terminal is displayed. Connect with In addition, in the automatic access method, if a mobile communication terminal attempts to access a home access network from the list of accessible network networks and fails, the roaming network (entered by the subscriber or a roaming network entered by the subscriber) is referred to the roamable network information. A roaming network), a method of selecting any one of the base stations discovered by the mobile communication terminal, and a method of selecting a base station having the best performance by comparing the reception power of the base stations received by the terminal.

Among the methods of manually selecting a communication network among the subscribers, it is difficult for the subscriber to grasp the network information directly and it is not easy to input the network information into the terminal or the subscriber identification card. The main method is to select a base station with the best performance.

However, when the mobile communication provider has negotiated one-to-many, it takes a lot of time for cell search and radio wave environment measurement to selectively connect with any one of a plurality of communication networks, resulting in a deterioration in service quality.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described disadvantages, and provides an asynchronous mobile communication system and a roaming control method in the system, which can reduce the searching time of a roaming terminal and increase the roaming success rate. There is.

The asynchronous mobile communication system of the present invention for achieving the above-described technical problem is a plurality of Node B to operate as a base station for the wireless section communication with the mobile communication terminal, a wireless for controlling the Node B connected to the plurality of Node B An asynchronous mobile communication system including a network controller and a switch connected to the plurality of wireless network controllers to perform a call exchange for providing a service to a mobile communication terminal, the asynchronous mobile communication system being connected to the wireless network controller and using a plurality of channels. An induction node B is connected to a mobile communication terminal and includes at least one roaming channel for transmitting a control signal with a power intensity greater than that of other channels among the plurality of channels.

In addition, the roaming control method of the present invention includes a plurality of Node Bs, a radio network controller, a switch, and an induction node B including at least one roaming channel for transmitting a control signal with a power intensity greater than that of other channels among the plurality of channels. A roaming control method in an asynchronous mobile communication system, wherein a mobile communication terminal searches for a roamable communication network and accesses to a roaming cell using the roaming channel of the induction node B, thereby performing location registration for the mobile communication terminal. step; Instructing the handover node B to handover to the mobile communication terminal according to a service request of the mobile communication terminal; And performing the handover by the mobile communication terminal.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Hereinafter, the mobile communication terminal may be any one of a mobile communication terminal roaming by inserting a mobile communication terminal having a roaming function or a subscriber identification card into the terminal itself, and for convenience of description, referred to as a 'mobile communication terminal'. Collectively. In addition, the mobile communication terminal may roam by selecting any one of a plurality of communication networks by a manual or automatic access method, and in particular, a case in which a base station having the best performance among neighboring base stations is selected and roams.

1 is a block diagram of an asynchronous mobile communication system according to the present invention.

As shown, the asynchronous mobile communication system is connected to the Node Bs 12, 14 and 16 and the Node Bs 12, 14 and 16 as base stations for wireless section communication with the mobile communication terminal to control the Node B. An asynchronous exchange (MSC) 26 and an asynchronous exchange connected to a radio network controller (RNC) 22 and 24, a plurality of radio network controllers 22 and 24 to perform a call exchange for providing a service to a mobile communication terminal. Is connected to, and consists of a core network 30 to provide a core function for a mobile communication service. In addition, the asynchronous mobile communication system of the present invention further includes at least one induction node B 18 connected to the radio network controller 24.

In general, the Node Bs 12, 14, and 16 divide the serviceable area into three or more sectors, and each sector consists of a plurality of cells. In addition, the Node Bs 12, 14, and 16 actually transmit information for voice or data services through a traffic channel, and control signals or auxiliary signals for transmitting and receiving traffic information through a control channel. A traffic channel and a control channel are allocated at a ratio of about 9: 1, and the mobile communication terminal selects an access target base station using information included in a common pilot channel (CPICH) among control channels.

Therefore, if the ratio of the control channel including the common pilot channel is increased than the traffic channel, the output of the control channel can be increased, and as a result, the mobile communication terminal will select a base station having a large output of the control channel. Accordingly, in the present invention, the mobile communication system is configured by adding at least one induction node B 18 to induce roaming of the mobile communication terminal, and the control channel allocation rate is assigned to a plurality of channels used in the induction node B 18. By including this high at least one roaming channel, roaming of the mobile communication terminal is induced.

When the induction node B 18 is installed in a place where the roaming mobile communication terminal first searches for a roaming communication network, such as an airport, the roaming mobile communication terminal recognizes a roaming channel of the induction node B 18 with strong radio wave strength, The roaming channel allows quick and easy access to the cell served by the roaming channel.

In addition, after the mobile communication terminal accesses the induction node B 18, in order to use an actual voice or data service, a traffic channel must be used. The roaming channel to which the mobile communication terminal is currently connected is a channel assigned to the traffic channel. Since the amount is small, in order to provide a smooth voice or data service, handover is performed to a cell serviced by a normal channel (a channel having a traffic channel allocation rate higher than a control channel). That is, the mobile communication terminal performs a handover to another cell in the sector including the cell to which the mobile terminal initially accesses.

2 is a view for explaining a concept of roaming control in an asynchronous mobile communication system according to the present invention.

The induction node B 18 is preferably installed at a place such as an airport, and the mobile communication terminal 100 searches for a roaming communication network to be connected for the first time at a place such as an airport. In this case, since the induction node B 18 includes at least one roaming channel having a high control channel allocation, the mobile communication terminal receives information included in a common pilot channel of a roaming channel having a high control channel allocation, that is, a high propagation strength. Reference is made to the induction node B 18.

For example, the serviceable area by the induction node B 18 is divided into three sectors as shown in FIG. 2, and the mobile communication terminal has a control channel allocation amount among a plurality of channels used by the induction node B 18. Roaming is induced by this high channel and connected to the corresponding cell (roaming cell) in sector 1.

In this way, after the roaming mobile communication terminal completes communication selection and completes communication preparation, the induction node B 18 causes the mobile communication terminal 100 to perform a handover to a cell to which another channel in the same sector is allocated. The mobile communication terminal 100 is connected to the node B (16) through a general channel to use the actual service. Here, the handover preferably uses a network directed handover method. Accordingly, the mobile communication terminal initially accesses a roaming cell to which a channel FA2 having a high control channel allocation is allocated, and then accesses a cell to which a general channel FA1 is allocated under the control of the induction node B 18. You will use the service.

Here, the network indication handover does not determine and instruct the handover in the access network (wireless network controller) according to the performance of the neighbor cell measured by the mobile communication terminal, but the mobile communication in the access network due to the needs of the mobile communication system. It means a handover made by triggering a handover to the terminal.

In addition, when the induction node B 18 requests that the mobile communication terminal 100 performs the RRC CONNECTION ESTABLISHMENT, when the mobile communication terminal 100 requests to perform the RADIO BEARER ESTABLISHMENT, the radio bearer When requesting to perform RADIO BEARER RECONFIGURATION, when requesting to perform TRANSPORT CHANNEL RECONFIGURATION, when requesting to perform PHYSICAL CHANNEL RECONFIGURATION. In one case, it is possible to request the mobile communication terminal 100 to perform a handover to the Node B 16, and when requesting to perform an RRC CONNECTION ESTABLISHMENT, it is preferable to request the handover.

3 is a view for explaining a roaming concept in an asynchronous mobile communication system according to the present invention. After the mobile communication terminal accesses to the induction node B, handover is performed to a neighbor cell in the same sector according to a request for performing a connection procedure of the mobile communication terminal. It shows the roaming control method when performed.

As shown, the mobile communication terminal searches for a roamable communication network for roaming and measures the signal strength received from a plurality of neighboring Node Bs (S10), wherein the signal strength transmitted through the roaming channel of the induction node B is Since it is the largest, the induced node B is selected as the roaming base station and connected to the cell (roaming cell) to which the roaming channel is assigned (S20). As described above, this is possible by controlling the control channel allocation amount larger than other channels for at least one channel among the plurality of channels used in the induction node B.

Subsequently, after the service for the roaming mobile communication terminal is allowed by performing a location registration and subscriber authentication process according to the request of the mobile communication terminal (S30), the terminal transmits a connection request message (RRC CONNECTION SETUP REQ) to the induction node B. If (S40), the induction node B instructs the mobile communication terminal to perform a handover with the response (RRC CONNECTION SETUP (INTER FA NETWORK DIRECTED H / O) (S50). The target cell information to be handed over to the communication terminal is also transmitted.

Accordingly, after the mobile communication terminal performs a handover to the handover target cell received from the induction node B (S60), and transmits a connection request message (RRC CONNECTION SETUP REQ) to the handover cell (S70), the node B moves By transmitting a response message (RRC CONNECTION SETUP COMLETE) to the communication terminal (S80), the connection procedure between the mobile communication terminal and the handover cell is completed.

On the other hand, when the roaming communication network to which the mobile communication terminal is connected in step S20 is determined, such information is stored in the mobile communication terminal, and when the power is turned off and the mobile communication terminal is started again, the mobile communication terminal automatically selects the previously selected terminal. The roaming network is accessed.

In FIG. 3, a case in which the induction node B instructs handover to the mobile communication terminal according to a request for performing an RRC connection connection procedure is not limited thereto. However, the present invention is not limited thereto. When requesting to perform RADIO BEARER ESTABLISHMENT, when requesting to perform RADIO BEARER RECONFIGURATION, when requesting to perform TRANSPORT CHANNEL RECONFIGURATION, physical In any case of requesting to perform a PHYSICAL CHANNEL RECONFIGURATION, the mobile terminal 100 may request a handover to the Node B 16.

As such, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without changing the technical spirit or essential features thereof. Therefore, the above-described embodiments are to be understood as illustrative in all respects and not as restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

According to the present invention, the roaming of the mobile communication terminal can be performed quickly by providing an induction node B in which at least one of the plurality of channels has a high allocation of the control channel for the traffic channel.

Claims (8)

A plurality of Node Bs operating as base stations for wireless section communication with a mobile communication terminal, a wireless network controller connected to the plurality of Node Bs to control the Node B, and connected to the plurality of wireless network controllers to a mobile communication terminal An asynchronous mobile communication system including an exchange for performing a call exchange to provide a service, An induction node B connected to the wireless network controller, connected to a mobile communication terminal using a plurality of channels, and including at least one roaming channel for transmitting a control signal with a power intensity greater than that of other channels among the plurality of channels; Asynchronous mobile communication system characterized in that it comprises. The method of claim 1, The roaming channel, the asynchronous mobile communication system, characterized in that the control channel is allocated at a rate higher than the control channel allocation rate in the other channel. The method according to claim 1 or 2, The induction node B instructs handover to the mobile communication terminal as the mobile communication terminal accesses and requests a service. The method of claim 3, wherein The service request is any one of a request for performing a connection procedure, a request for performing a radio bearer setup procedure, a request for performing a radio bearer reset procedure, a request for performing a transport channel reset procedure, and a request for performing a physical channel reset procedure. Roaming control method in asynchronous mobile communication system comprising a plurality of Node B, wireless network controller, switch and induction node B including at least one roaming channel for transmitting a control signal with a power intensity greater than other channels of the plurality of channels As Performing a location registration for the mobile communication terminal as the mobile communication terminal searches for a roamable communication network and accesses a roaming cell using the roaming channel of the induction node B; Instructing the handover node B to handover to the mobile communication terminal according to a service request of the mobile communication terminal; And Performing a handover by the mobile communication terminal; Roaming control method in an asynchronous mobile communication system comprising a. The method of claim 5, And instructing the induction node B to handover to the mobile communication terminal is a step of transmitting handover target cell information along with a handover instruction. The method according to claim 5 or 6, And instructing the induction node B to handover to a mobile communication terminal instructing handover to an adjacent cell in the same sector as the roaming cell. The method according to claim 5 or 6, The service request of the mobile communication terminal may be any one of a request for performing an access procedure, a request for performing a radio bearer setup procedure, a request for performing a radio bearer reset procedure, a request for performing a transport channel reset procedure, and a request for performing a physical channel reset procedure. Roaming control method in communication system.

Images