KR20050036399A - Method for selecting mobile system in wireless communication terminal - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

The present invention relates to a system selection method in a wireless communication terminal.

2. The technical problem to be solved by the invention

In the present invention, in performing a process (BSR) for selecting a higher priority system among a plurality of serviceable systems, the wireless communication terminal generally takes advantage of the fact that it is most likely to reconnect to a recently connected system. The system with the highest priority, the most recently used system (MRU), and the M systems with higher priority than the most recently used system (MRU) are searched in order to select a higher priority system in a shorter time. The purpose of the present invention is to provide a method of selecting a system in a wireless communication terminal.

3. Summary of the Solution of the Invention

According to an aspect of the present invention, there is provided a system selection method of a wireless communication terminal, comprising: a first step of the wireless communication terminal selecting a usage system using a most recently used system (MRU) and a highest priority system; After the wireless communication terminal generates an optimal service rescan list MT_BSR_List by limiting the number of priority systems higher than a most recently used system (MRU) to a predetermined value or less, the optimal service rescan list MT_BSR_List Searching for systems and selecting connectable systems according to; And a third step of the wireless communication terminal selecting a connectable system by searching for higher priority systems than a most recently used system (MRU).

4. Important uses of the invention

The present invention is used in a wireless communication terminal.

Description

System selection method in wireless communication terminal {METHOD FOR SELECTING MOBILE SYSTEM IN WIRELESS COMMUNICATION TERMINAL}

The present invention relates to a method of selecting a system in a wireless communication terminal. More particularly, in selecting a system, the wireless communication terminal has a higher priority in a short time due to the fact that it is likely to reconnect to a recently connected system. A system selection method in a wireless communication terminal for selecting a system of the ranking.

In the present invention, a wireless communication terminal is an analog mobile communication terminal, a personal mobile communication terminal (PCS), a personal digital terminal (PDA), a smart phone, a next-generation mobile communication terminal (IMT-2000) such as a mobile terminal capable of mobile communication while the individual Say. In the following example, a mobile communication terminal will be described as an example.

In addition, in the present invention, the system refers to an operation system of a mobile communication service provided by each mobile communication service provider to provide a service to a mobile communication terminal, and according to the development of mobile communication technology, an analog method, a digital cellular method, and a PCS method. There are many ways to mix things together, and the system can be different as well.

A typical mobile communication system divides an entire service area into a plurality of base station areas, constitutes cells, which are small service areas, and centrally controls base stations with mobile switching centers (MSCs) to allow subscribers to inter-cell. It allows you to continue the call while moving.

That is, the mobile communication terminal acquires a signal through interworking with the base station, and receives the call service by informing the mobile communication system of its location and whether or not it is registered using the obtained signal. First, when the user turns on the mobile communication terminal, the mobile communication terminal selects a base station to be tuned in the initialization state (Mobile Station Initialization Station) and acquires base station information (Acuisition). At this time, since each base station transmits a unique pilot signal, the mobile communication terminal selects a base station transmitting the strongest pilot signal. In addition, the mobile communication terminal periodically selects a base station to be serviced by exchanging a signal with a base station, and receives a continuous service even while moving by handoff.

Handoff refers to the automatic switching of the current call channel when moving between sectors within a cell or moving from one cell to another. The handoff is performed in three stages: measuring parameters, determining an appropriate handoff time from the collected information, and executing a handoff to establish a new link and release the previous link.

On the other hand, the type of handoff is divided into intra-cell handoff, inter-cell handoff and intra-network handoff according to the range in which the handoff occurs. . Handoff in a cell is to change the channel being used within cell coverage where the mobile communication terminal is currently located. In this case, there is no new connection establishment or release. The handoff between cells is a method in which the mobile communication terminal continues the existing communication through the new base station when the mobile communication terminal cannot continue the connection due to the cell boundary of the base station. In this case, handoff delay and cell loss occur due to connection resetting and release of the existing connection. Finally, handoff between manganeses is to perform handoff when the mobile communication terminal moves between different networks.

As such a handoff is required in the mobile communication system, a service for providing a mobile communication service between different mobile communication systems is required. As such, other mobile communication providers can be jointly used by different mobile communication providers. Providing the same mobile communication service to subscribers is called a roaming service.

For example, when several mobile carriers establish their own service networks, the service providers cooperate with each other to provide services by interworking service networks with each other regardless of which service provider the user subscribes to. And broaden the service area. In addition, when roaming is made overseas, even if a user subscribes to a domestic specific mobile service provider, the user can use a mobile communication terminal with his / her phone number anywhere in the world.

At this time, the mobile communication providers have a roaming list called "PRL (Preferred Roaming List)" which is a list of identifiers (IDs) of the mobile communication systems that support roaming in the subscriber's mobile communication terminal for roaming service. The roaming list (PRL) includes an Acquisition Table and a System Table for each region in which the system is provided.

The acquisition table is classified according to an acquisition type to which each index is assigned, and includes information indicating the number of channels or blocks that can be serviced for each acquisition type and corresponding channels or blocks. The acquisition type indicates a system capable of service, such as an analog system, a digital cellular system, and a PCS system.

In addition, the system table includes "SID (system identifier)", "NID (network identifier)", service availability, region information, priority, acquisition index, roaming indicator, and the like. It is defined. An acquisition index is an index assigned to an acquisition type of the acquisition table. The acquisition index is required for matching between the system table and the acquisition table, and " SID " is information that can identify the system. Since the identification information of the "SID" is the same value can be regarded as the same system.

Meanwhile, when the mobile communication terminal acquires a signal transmitted from the mobile communication system during the initialization operation, the mobile communication terminal attempts to acquire a channel according to the roaming list PRL. In addition, when the mobile communication terminal moves to another area or moves to another mobile communication system (eg, an analog system), roaming is possible by searching for a channel in the roaming list (PRL).

That is, the mobile communication terminal periodically performs a channel search according to the roaming list (PRL) in the initialization state (Mobile Station Initialization Station), which is entered into the "BSR (Better Service Rescan)" (No Service) state. Search for high priority systems).

"BSR" creates a list of systems of higher priority than the system currently being serviced, and then searches in order according to the list, so that a system of higher priority than the system currently being serviced is connectable. You will select that system and try to connect. However, as a result of performing the "BSR", if the system with a higher priority than the system currently being serviced is not selected, the system which was recently serviced according to the most recently used table (MRU) (the system currently being serviced) Select channel again.

2 is a flowchart illustrating a system selection method in a mobile communication terminal according to a conventional method.

First, the mobile communication terminal attempts to connect with the base station through a channel corresponding to the acquisition type in the order of the acquisition table, and when the connection is made with the base station, information about a system corresponding to the connected base station, that is, a system identifier (SID) and a network Receives and stores an identifier (NID).

Thereafter, the mobile communication terminal periodically performs a next procedure (BSR) in an idle state. That is, the mobile communication terminal retrieves information (SID, NID) of the most recently used system (MRU: Most Recently Used) from a roaming list (PRL) (201), and most recently used system (MRU). It is determined whether the system has the highest priority in the current region (202).

If the determination result 202, the system having the highest priority is selected (MRU: Most Recently Used) (206), and if the determination result 202, the system having the highest priority is not the roaming list (PRL) By using the Preferred Roaming List (203), all the systems of the highest priority in the current region and the higher priority than the most recently used system (MRU) are sequentially searched (203) to select a connectable system (204, 205). In this case, if a system having a higher priority than most recently used system (MRU) is not selected, the most recently used system (MRU) is selected (206).

Such a conventional "BSR" scheme generally has a long initial state by searching for all channels of a system having a higher priority than a previously connected system despite the possibility of reconnecting to a previously connected system. As a result, there is a problem in that a no service state becomes longer.

The present invention has been proposed to solve the above problems, and in recent years, in performing a procedure (BSR) for selecting a higher priority system among a plurality of systems that a wireless communication terminal can service, a recent connection is generally performed. Using the fact that there is a high possibility of reconnecting to the system, the system is searched for the highest priority system, most recently used (MRU), and M systems with higher priority than most recently used (MRU). Accordingly, an object of the present invention is to provide a method of selecting a system in a wireless communication terminal for selecting a system having a higher priority within a short time.

According to an aspect of the present invention, there is provided a system selection method in a wireless communication terminal, wherein the wireless communication terminal selects a use system using a most recently used system (MRU) and a highest priority system. Stage 1; After the wireless communication terminal generates an optimal service rescan list MT_BSR_List by limiting the number of priority systems higher than a most recently used system (MRU) to a predetermined value or less, the optimal service rescan list MT_BSR_List Searching for systems and selecting connectable systems according to; And a third step of the wireless communication terminal selecting a connectable system by searching for higher priority systems than a most recently used system (MRU).

In addition, the present invention is a method of selecting a system in a wireless communication terminal, the wireless communication terminal using a roaming list (PRL: Preferred Roaming List) from the system of the highest priority in the current region to the most recently used system (MRU: Most Recently) Searching for a system having a higher priority than Used); Generating, by the wireless communication terminal, an optimal service rescan list (MT_BSR_List) by limiting the number of priority systems higher than the most recently used system (MRU) to be less than or equal to a preset value; And a third step of searching for systems according to the generated optimal service re-search list MT_BSR_List and selecting a connectable system.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of an embodiment of a mobile communication system to which the present invention is applied.

As shown in FIG. 1, a mobile communication system to which the present invention is applied, each transmits a unique pilot signal and is connected to a mobile communication terminal and a radio channel under the control of the base station controller 14 to perform communication. (11, 12, 13), a device international controller 14 for controlling and managing the base stations (11, 12, 13), and a mobile communication network (15).

3 is a flowchart illustrating a system selection method in a mobile communication terminal according to the present invention.

First, the mobile communication terminal attempts to connect with the base station through a channel corresponding to the acquisition type in the order of the acquisition table, and when the connection is made with the base station, information about a system corresponding to the connected base station, that is, a system identifier (SID) and a network Receives and stores an identifier (NID).

Thereafter, the mobile communication terminal periodically performs a next procedure (BSR) in an idle state. That is, the mobile communication terminal retrieves information (SID, NID) of the most recently used system (MRU: Most Recently Used) from a roaming list (PRL) (301), and most recently used system (MRU). It is determined whether the system has the highest priority in this current region (302).

If the determination result 302, the system having the highest priority is selected (MRU: Most Recently Used) (310), and if the determination result 302, the system with the highest priority is not roaming list (PRL) Use the Preferred Roaming List to identify the number of systems with higher priority than most recently used systems (MRUs) (303, 304).

As a result of the check 304, if the number of priority systems higher than the most recently used system (MRU) is less than the preset number (N), the roaming list (PRL: Preferred Roaming List) is used as the highest priority in the current region. All systems having a higher priority than the most recently used system (MRU) are sequentially searched (307) to select a connectable system (308, 309). As a result of performing the process 307, if a system having a higher priority than the most recently used system (MRU) is not selected, the system uses the most recently used system (MRU) (310).

On the other hand, if the number 304 of the priority system higher than the most recently used system (MRU: Most Recently Used) is greater than or equal to the preset value (N), then the optimal service rescan list MT_BSR_List is generated (305). In step 309, the connectable system is selected based on the generated optimal service re-search list MT_BSR_List.

A process of generating an optimal service rescan list MT_BSR_List will be described in more detail with reference to FIG. 4.

FIG. 4 is a detailed flowchart illustrating a process of generating an optimal service rescan list MT_BSR_List among system selection methods in a mobile communication terminal according to the present invention.

First, the mobile communication terminal extracts a system having the highest priority in the current region from a roaming list (PRL) and adds it to the optimal service rescan list MT_BSR_List (401).

In addition, the most recently used system (MRU: Most Recently Used) is added to the optimal service re-search list (MT_BSR_List) with reference to the MRU table (402), and the most recently used system except the highest priority system in the current region (MRU: Most) is used. A system of a predetermined number M is extracted from systems having a higher priority than Recently Used and sequentially added to the optimal service rescan list MT_BSR_List (403).

After that, the most recently used system (MRU: Most Recently Used) is added again, and the remaining ones that are not added to the optimal service re-search list (MT_BSR_List) among the systems having higher priority than the most recently used system (MRU) are again added. The system may be configured to extract a predetermined number of systems and add them to the optimal service rescan list MT_BSR_List in order.

At this time, the preset values M and N may be set to appropriate values by the mobile service provider or the mobile terminal manufacturer, and the optimal service rescan list MT_BSR_List is also updated because the priority of the system is changed when the area is changed. .

In addition, when a system is selected using the optimal service re-search list (MT_BSR_List) generated by the above method, the system with the highest priority is searched, and then the most recently used system (MRU), and then Significantly re-captures the time it takes to recapture the system from idle by searching for M systems that have a higher priority than the rest of the most recently used systems (MRUs) and then most recently used systems (MRUs). Can be reduced.

On the other hand, the system selection process of the mobile communication terminal as described above is " BSR " which is executed periodically after the end of a normal call or in an idle state (for example, every 3 minutes for a CDMA system and every 2 minutes for an AMPS system). It can be applied to a city (a process of searching for a higher priority system by entering a No Service state).

The present invention described above is capable of various substitutions, modifications, and changes without departing from the spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

As described above, the present invention provides a process of searching for a system having a higher priority by entering a No Service state (BSR) for selecting a system having a higher priority from among a plurality of systems serviceable by the wireless communication terminal. In performing the above method, unlike the conventional method of selecting a connectable system by sequentially searching for all systems having the highest priority from the highest priority system in the current region to the most recently used system (MRU), the highest priority in the current region. System, followed by M Recently Used System (MRU: Most Recently Used), followed by M Most Highly Used System (MRU: Most Recently Used). (MRU: Most Recently Used) in turn to find the time it takes to recapture the system while idle. Hi There may reduce effectiveness.

1 is a configuration diagram of an embodiment of a mobile communication system to which the present invention is applied.

2 is a flowchart illustrating a system selection method in a mobile communication terminal according to a conventional method.

3 is a flowchart illustrating a method for selecting a system in a mobile communication terminal according to the present invention.

4 is a detailed flowchart illustrating a process of generating an optimal service rescan list MT_BSR_List among system selection methods in a mobile communication terminal according to the present invention.

* Explanation of symbols on the main parts of the drawing

11,12,13: base station 14: base station controller

15: Mobile communication network

Claims (4)

In the system selection method in a wireless communication terminal, A first step of the wireless communication terminal selecting a use system using a most recently used system (MRU) and a highest priority system; After the wireless communication terminal generates an optimal service rescan list MT_BSR_List by limiting the number of priority systems higher than a most recently used system (MRU) to a predetermined value or less, the optimal service rescan list MT_BSR_List Searching for systems and selecting connectable systems according to; And A third step in which the wireless communication terminal selects a connectable system by searching for higher priority systems than a most recently used system (MRU); System selection method in a wireless communication terminal comprising a. In the system selection method in a wireless communication terminal, A first step of the wireless communication terminal searching for a system having a higher priority than the most recently used system (MRU: most recently used) in the current region by using a roaming list (PRL); Generating, by the wireless communication terminal, an optimal service rescan list (MT_BSR_List) by limiting the number of priority systems higher than the most recently used system (MRU) to be less than or equal to a preset value; And A third step of searching for systems according to the generated optimal service re-search list MT_BSR_List and selecting a connectable system System selection method in a wireless communication terminal comprising a. The method according to claim 1 or 2, The process of generating the optimal service re-search list (MT_BSR_List), A fourth step of the wireless communication terminal extracting a system having the highest priority in the current region from a Preferred Roaming List (PRL) and adding it to the optimal service rescan list (MT_BSR_List); A fifth step of the wireless communication terminal adding the most recently used system (MRU) to the optimal service rescan list MT_BSR_List; And The wireless communication terminal extracts a system having a higher priority than the most recently used system (MRU) from the roaming list (PRL) except the system having the highest priority in the current region by a preset value (M). 6th step of adding to the optimal service rescan list MT_BSR_List System selection method in a wireless communication terminal comprising a. The method of claim 3, wherein A seventh step of the wireless communication terminal re-adding the most recently used system (MRU); And The wireless communication terminal presets a system that is not added to the optimal service re-search list MT_BSR_List among systems having a higher priority than a most recently used system (MRU) from a roaming list (PRL). An eighth step of extracting M) and adding it to the optimal service rescan list MT_BSR_List System selection method in a wireless communication terminal further comprising.