CN106559770B

CN106559770B - Network selection method and system of foreign roaming boundary

Info

Publication number: CN106559770B
Application number: CN201510621241.2A
Authority: CN
Inventors: 王大亮
Original assignee: Leadcore Technology Co Ltd; Datang Semiconductor Design Co Ltd
Current assignee: Chenxin Technology Co ltd
Priority date: 2015-09-25
Filing date: 2015-09-25
Publication date: 2020-09-11
Anticipated expiration: 2035-09-25
Also published as: CN106559770A

Abstract

The invention provides a network selection method and a network selection system of a foreign roaming boundary. A network selection method of a foreign roaming boundary comprises the following steps: obtaining an air interface MCC list according to PLMN information obtained from the air interface; determining that the air interface MCC list comprises a local MCC and a foreign MCC; judging whether the MCC of the first PLMN network which resides currently is the same as the local MCC, if so, registering the first PLMN network, if not, filtering the foreign MCC in the air interface MCC list, selecting to reside a second PLMN network in the PLMN network corresponding to the filtered air interface MCC list, and registering the second PLMN network. The invention realizes that the mobile terminal preferentially resides in the proper local PLMN network under the condition that the local network and the foreign roaming network are crossed and coexisted, thereby effectively saving the user charge and improving the network selection speed.

Description

Network selection method and system of foreign roaming boundary

Technical Field

The invention relates to the field of network selection methods, in particular to a network selection method and a network selection system for a foreign roaming boundary.

Background

At present, with the rapid development of social economy, the demand of people for travel and business trip to different places or foreign countries is increasing. At the same time, the performance of wireless communication devices is increasingly demanded.

If the process is selected according to PLMN (public Land Mobile network) in 3GPP (3rd Generation Partnership Project)23.122 protocol, the Mobile terminal needs to select network and reside according to the priority of PLMN when being powered on or recovering coverage:

for example, RPLMN- > HPLMN/EHPLMN- > UPLMN- > OPLMN- > PLMN with high quality and low quality-PLMN selection sequence. In the foreign roaming boundary area, the situation that the home network and the foreign roaming network coexist in a cross mode exists, how to quickly reside in a proper network in the network environment and how to quickly select a network after moving to the non-cross network environment, the network searching time is too long in the realistic problem scenes, the user experience is further influenced, and meanwhile, if the home network can be preferentially resided in the foreign roaming boundary area, the problem of user expense is effectively improved. Therefore, how to solve the problems of long network searching time and unreasonable user charges caused by the foreign roaming boundary area is an urgent problem to be solved in the industry.

Disclosure of Invention

The invention provides a network selection method and a network selection system of a foreign roaming boundary, which are used for solving the problem of overhigh user charge caused by a foreign roaming boundary area.

The embodiment of the invention adopts the following technical scheme:

the invention provides a network selection method of a foreign roaming boundary, which comprises the following steps:

obtaining an air interface MCC list according to the MCC information acquired from the air interface;

determining that the air interface MCC list comprises a local MCC and a foreign MCC;

judging whether the MCC of the first PLMN network which resides currently is the same as the local MCC, if so, registering the first PLMN network, if not, filtering the foreign MCC in the air interface MCC list, selecting to reside a second PLMN network in the PLMN network corresponding to the filtered air interface MCC list, and registering the second PLMN network.

Selecting to reside a second PLMN network in the PLMN network corresponding to the filtered empty MCC list, which specifically includes:

and selecting the second PLMN network to reside in the PLMN network corresponding to the filtered air interface MCC list through a PLMN selection process in a 3GPP23.122 protocol.

Preferably, the obtaining an air interface MCC list according to PLMN information acquired from the air interface specifically includes:

and if the acquired cell broadcast contains the MCC which is not in the air interface MCC list acquired in advance, updating the air interface MCC list according to the MCC in the cell broadcast.

Preferably, the obtaining an air interface MCC list according to PLMN information acquired from the air interface specifically includes: and obtaining an air interface MCC list according to PLMN information periodically acquired from the air interface.

Preferably, the obtaining an air interface MCC list according to PLMN information periodically acquired from the air interface specifically includes:

judging whether the air interface MCC list is consistent with a pre-obtained air interface MCC list or not, if not, reducing the period to a first period, wherein the first period is more than or equal to a preset minimum period threshold value; and if so, prolonging the period to a second period, wherein the second period is less than or equal to a preset maximum period threshold value.

Preferably, after obtaining the air interface MCC list according to the PLMN information acquired from the air interface, the method further includes:

and if the air interface MCC list only comprises the local MCC, selecting a resident third PLMN network in the network system supported by the local area of the operator through a preset PLMN selection process, and registering the third PLMN network.

and if the air interface MCC list only comprises the foreign MCC, selecting a resident fourth PLMN network in the network system supported by the foreign region of the operator through a preset PLMN selection process, and registering the fourth PLMN network.

The invention also provides a network selection system of the foreign roaming boundary, which comprises:

an obtaining unit, configured to obtain an air interface MCC list according to PLMN information obtained from the air interface;

a first MCC detecting unit, configured to determine that the air interface MCC list includes a local MCC and a foreign MCC;

a determining unit, configured to determine whether the MCC of the currently residing first PLMN network is the same as the local MCC, if so, register the first PLMN network, otherwise, filter the foreign MCC in the empty MCC list, select to reside a second PLMN network in the PLMN network corresponding to the filtered empty MCC list, and register the second PLMN network.

The judging unit is used for: judging whether the MCC of the first PLMN network which resides currently is the same as the local MCC, if so, registering the first PLMN network, if not, filtering the foreign MCC in the air interface MCC list, selecting to reside a second PLMN network in the PLMN network corresponding to the filtered air interface MCC list through a PLMN selection process in a 3GPP23.122 protocol, and registering the second PLMN network.

Preferably, the obtaining unit is specifically configured to:

Preferably, the obtaining unit is specifically configured to: and obtaining an air interface MCC list according to PLMN information periodically acquired from the air interface.

Preferably, the obtaining unit is specifically configured to:

Preferably, the mobile station further includes a second MCC detecting unit, connected to the obtaining unit, and configured to determine that the air interface MCC list includes only a local MCC, and select to reside in a third PLMN network in a network standard supported by a local area of an operator through a preset protocol selection process, and register the third PLMN network.

Preferably, the mobile station further includes a third MCC detecting unit, connected to the obtaining unit, configured to determine that the air interface MCC list includes only an alien MCC, and select to reside in a fourth PLMN network in a network standard supported by an operator alien region through a preset protocol selection procedure, and register the fourth PLMN network.

Compared with the prior art, the network selection method and the system of the foreign roaming boundary provided by the invention have the following beneficial effects:

the invention selects the resident second PLMN network after filtering the foreign MCC in the air interface MCC list, realizes that the mobile terminal preferentially resides in the proper local PLMN network under the condition of cross coexistence of the local network and the foreign roaming network, can effectively save user charge and improve the network selection speed; after the mobile terminal moves to a non-cross network environment, network selection is carried out by filtering a network system which is not supported by an operator in the area, so that rapid network selection is realized, the network selection residence process can be effectively accelerated, the period for acquiring PLMN information from an air interface is adjusted according to the change condition of an air interface MCC list, and the power consumption of the mobile terminal can be effectively reduced.

Drawings

Fig. 1 is a flowchart of a network selection method for a foreign roaming boundary according to a first embodiment of the present invention.

Fig. 2 is a flowchart of a method for selecting a network at a foreign roaming boundary according to a second embodiment of the present invention and a flowchart of a method for selecting a network at a foreign roaming boundary according to a third embodiment of the present invention.

Fig. 3 is a flowchart of a third embodiment of a network selection method for a foreign roaming boundary according to the present invention.

Fig. 4 is a block diagram illustrating a first embodiment of a network selection system for a foreign roaming boundary according to the present invention.

Fig. 5 is a block diagram of a second embodiment of a network selection system of a foreign roaming boundary provided in the present invention.

Fig. 6 is a block diagram illustrating a third embodiment of a network selection system for a foreign roaming boundary according to the present invention.

Detailed Description

In order to make the technical problems solved, technical solutions adopted and technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Fig. 1 shows a method flowchart of a first embodiment of a network selection method of a foreign roaming boundary provided by the present invention. A network selection method of the foreign roaming boundary of the embodiment is mainly executed by the mobile terminal. Among them, the mobile terminal includes but is not limited to: cell-phone, panel computer, wearable equipment etc. this method includes the following step:

s11: and obtaining an air interface MCC list according to the PLMN information acquired from the air interface.

Specifically, the mobile terminal extracts the MCC from the PLMN information acquired by the air interface, and stores the MCC into the mobile terminal to obtain a list of MCCs of the air interface. The PLMN (Public Land Mobile Network) includes MCC (Mobile country code) and MNC (Mobile Network code), where the MCC is the first three digits of the PLMN, for example, 46000 for PLMN in china Mobile and 460 for MCC.

S12: and determining that the air interface MCC list comprises the local MCC and the foreign MCC.

Specifically, the local MCC is an MCC in the current air interface MCC list that is the same as the MCC of the HPLMN in the phone card, the foreign MCC is an MCC in the current air interface MCC list that is different from the MCC of the HPLMN in the phone card, the HPLMN is a home PLMN, the phone card may be an SIM card or an USIM card, and the mobile terminal determines that the air interface MCC list includes the local MCC and the foreign MCC one by comparing the MCC of the HPLMN in the phone card with each MCC in the air interface MCC list, which indicates that the local network and the international roaming network exist in the current air interface MCC list of the mobile terminal at the same time, that is, the mobile terminal is in.

For example, obtaining a HPLMN (Home PLMN, i.e. Home PLMN) in a SIM card or USIM card in the mobile terminal; comparing whether the MCC in the air interface MCC list is the same as the MCC of the HPLMN in the SIM card, if there is the same MCC and there are different MCCs, it can be determined that the air interface MCC list includes a local MCC and an external MCC, the local MCC is the same MCC as the MCC of the HPLMN in the air interface MCC list, and the external MCC is a MCC different from the MCC of the HPLMN in the air interface MCC list.

S13: judging whether the MCC of the first PLMN network which resides currently is the same as the local MCC, if so, registering the first PLMN network, if not, filtering the foreign MCC in an air interface MCC list, selecting to reside a second PLMN network in the PLMN network corresponding to the filtered air interface MCC list, and registering the second PLMN network.

For example, the mobile terminal determines whether the MCC of the currently residing first PLMN network is the same as the local MCC, if so, registers the first PLMN network, and if not, filters the foreign MCC in the empty MCC list, selects to reside the second PLMN network in the PLMN network corresponding to the filtered empty MCC list through a preset protocol, that is, selects to reside the second PLMN network only from the PLMN network corresponding to the local MCC, and registers the second PLMN network. For example, the second PLMN network may be selected to reside in the PLMN network corresponding to the filtered air interface MCC list through a PLMN selection procedure in the 3GPP23.122 protocol.

The currently camped first PLMN network is a PLMN network in which the mobile terminal currently resides, and is selected to reside in PLMN information acquired through a preset PLMN selection procedure in an air interface, for example, the mobile terminal selects to reside in the first PLMN network in PLMN information acquired through a PLMN selection procedure in a 3GPP23.122 protocol in the air interface.

In summary, the embodiment realizes that the mobile terminal preferentially camps on the appropriate home PLMN network under the cross coexistence condition that the home network and the foreign roaming network cross coexist, so that the user cost can be effectively saved.

Fig. 2 shows a method flowchart of a second embodiment of the network selection method of the foreign roaming boundary provided by the present invention. A network selection method of the foreign roaming boundary of the embodiment is mainly executed by the mobile terminal. Among them, the mobile terminal includes but is not limited to: compared with a network selection method of a foreign roaming boundary, the present embodiment differs from the first embodiment in that: according to the change condition of an air interface MCC list, the period of acquiring PLMN information from the air interface is shortened or prolonged, and the power consumption of the mobile terminal can be effectively reduced, and the method comprises the following steps:

s21: and obtaining an air interface MCC list according to the PLMN information acquired from the air interface.

Specifically, the mobile terminal extracts the MCC from the PLMN information acquired by the air interface, and stores the MCC into the mobile terminal to obtain a list of MCCs of the air interface.

S21 in this embodiment includes: the method comprises the steps of obtaining an air interface MCC list according to PLMN information periodically acquired from an air interface, wherein the period in the periodic acquisition process can be fixed or unfixed, the step can be realized by periodically updating a timer, and the initial duration of the step is a minimum period threshold Tmin.

Preferably, in order to reduce the power consumption of the mobile terminal in network selection, whether the empty MCC list is consistent with a pre-obtained empty MCC list or not can be judged, if not, the period is shortened to a first period, and the first period is greater than or equal to a preset minimum period threshold; if yes, the period is prolonged to a second period, and the second period is less than or equal to a preset maximum period threshold value.

Specifically, a minimum period threshold Tmin and a maximum period threshold Tmax are preset, an acquired air interface MCC list a1 is obtained according to currently acquired PLMN information, whether the air interface MCC list a1 is consistent with a pre-acquired air interface MCC list a2 is judged, if not, the current period T0 is reduced to a first period T1, and the first period T1 is greater than or equal to the preset minimum period threshold Tmin; if yes, the current period T0 is extended to a second period T2, the second period T2 is less than or equal to a preset maximum period threshold Tmax, and the empty MCC list a1 is the current MCC list. The air interface MCC list a1 is obtained periodically from an air interface according to a period T0 or obtained by triggering a background network search through other programs, the pre-obtained air interface MCC list a2 is an MCC list obtained before obtaining the current MCC list, and may be a most adjacent MCC list updated last time before obtaining the current MCC list, and the air interface MCC list a2 may be obtained through PLMN information periodically obtained from the air interface, or may be obtained by triggering and reading a cell broadcast message through other programs in the mobile terminal.

The other program triggering processes specifically include: determining that the acquired cell broadcast includes an MCC that is not in the pre-obtained air interface MCC list, updating the air interface MCC list according to the MCC in the cell broadcast, and triggering other programs including updating the MCC list after detecting a new MCC under the conditions of reselection by the mobile terminal, coverage recovery, and the like, for example: the method comprises the steps that a mobile terminal acquires cell broadcast in a normal network selection process, whether the acquired cell broadcast contains MCC which is not in a pre-acquired air interface MCC list or not is judged, and if so, the air interface MCC list is updated according to the MCC in the cell broadcast; the mobile terminal acquires a reselection instruction input by a user, acquires cell broadcast, judges whether the acquired cell broadcast contains MCC which is not in a pre-acquired air interface MCC list, and if so, updates the air interface MCC list according to the MCC in the cell broadcast; and the mobile terminal detects that coverage is recovered, acquires cell broadcast, judges whether the acquired cell broadcast contains MCC which is not in the pre-acquired air interface MCC list, and if so, updates the air interface MCC list according to the MCC in the cell broadcast.

The above procedure for updating the empty MCC list is further explained by the following example:

a: the mobile terminal updates an air interface MCC list through a periodic updating timer, and the initial duration of the mobile terminal is the minimum value T;

b: after the periodic update timer is overtime, the mobile terminal acquires MCC information of an air interface in a background network searching mode, and the wireless resource management module/physical layer tries to read a signal cell broadcast message to acquire PLMN information of the air interface;

c: a wireless resource management module of the mobile terminal records air interface MCC information detected in the background network searching of the current round first, and the wireless resource management module is used for executing a preset PLMN selection process;

d: checking whether the background network searching process of the current round is finished: checking whether all the standard frequency points try to acquire empty PLMN (public land mobile network), if the process is not finished, executing C next to acquire PLMN information of the next frequency point; if the current round of network searching process is finished, next, executing step E, and further checking whether the current round of background network searching detects a new MCC:

e: after the network searching is completed in the current round, the wireless resource management module notifies the detected air interface MCC information to the network selection control module, and the network selection control module checks whether a new MCC is detected. And when the mobile terminal detects a new MCC during normal network selection, reselection or coverage restoration, updating and checking the maintained empty MCC list. If the new MCC is detected, G is executed next, and the mobile terminal updates an air interface MCC list; otherwise, indicating that no new MCC is detected, then executing step F, and changing the time length of the timer retrieved by the air interface MCC;

f: and indicating that no new MCC is detected in the round, and considering power consumption, gradually shortening or lengthening the time length of the timer for periodic retrieval of the air interface MCC by combining the change condition of each round of searching the air interface MCC according to different scenes for triggering MCC change detection. If the MCC at the air interface is not changed after a certain round of search is completed, the duration of the timer is gradually lengthened, and the maximum value of the duration can be N-hour level (the MCC is in different scenes such as timeout of a periodic timer, coverage recovery, reselection and the like, and the step length of the timer can be different). The process flow ends.

G: and detecting a new MCC by the PLMN search of the air interface in the round, updating the MCC list stored by the mobile terminal, and simultaneously considering resetting or shortening the time length of the timer for the periodic retrieval of the MCC at the air interface. When a new MCC is detected, the time length of the reset timer is the initial minimum value, so that the network environment of the mobile terminal can be determined as soon as possible in a short time.

In summary, in this embodiment, the period for acquiring PLMN information from the air interface is adjusted according to the change of the MCC list of the air interface, so that the power consumption of the mobile terminal can be effectively reduced.

S22: and determining that the air interface MCC list comprises the local MCC and the foreign MCC. This step is performed in the same manner as S12.

S23: judging whether the MCC of the first PLMN network which resides currently is the same as the local MCC, if so, registering the first PLMN network, if not, filtering the foreign MCC in an air interface MCC list, selecting to reside a second PLMN network in the PLMN network corresponding to the filtered air interface MCC list, and registering the second PLMN network. This step is performed in the same manner as S13.

Fig. 2 and fig. 3 are flow charts of a method for selecting a network at a foreign roaming boundary according to a third embodiment of the present invention. A network selection method of the foreign roaming boundary of the embodiment is mainly executed by the mobile terminal. Among them, the mobile terminal includes but is not limited to: compared with a second embodiment of the network selection method of the foreign roaming boundary, the second embodiment of the network selection method of the present embodiment is different in that the process change of network selection in the PLMN network after the mobile terminal moves to the non-cross network environment is added to realize fast network selection, and the method adds the following steps on the basis of the second embodiment:

after the step S21, steps S31 and S32 are included, wherein there is no precedence order between S31 and S32.

S31: and if the air interface MCC list only comprises the local MCC, selecting a resident third PLMN network in the network system supported by the local area of the operator through a preset PLMN selection process, and registering the third PLMN network.

Specifically, the mobile terminal compares the MCC of the HPLMN in the phone card with each MCC in the empty MCC list one by one, and if it is determined that the empty MCC list only includes a local MCC, selects a resident third PLMN network in a network format supported by a local area of an operator in the empty through a preset protocol selection flow, and registers the third PLMN network. For example, the preset PLMN selection procedure is a PLMN selection procedure in the 3GPP23.122 protocol. When the mobile terminal moves in the local network environment, the network is selected in the network system supported by the local area of the operator so as to realize quick network selection. For example, by combining the MCC and the SIM/USIM card, if it is detected that the local MCC is 460, that is, in china, the PLMN is 46000, which is a mobile card, only the system supported by the china mobile in china is searched, and the WCDMA system is not searched.

S32: and if the air interface MCC list only comprises the foreign MCC, selecting to reside a fourth PLMN network in the network system supported by the foreign area of the operator through a preset PLMN selection process, and registering the fourth PLMN network.

Specifically, the mobile terminal compares the MCC of the HPLMN in the phone card with each MCC in the air interface MCC list one by one, and if it is determined that the air interface MCC list only includes an alien MCC, selects a resident fourth PLMN network in a network standard supported by an operator alien region in the air interface through a preset PLMN selection flow, and registers the fourth PLMN network. For example, the preset PLMN selection procedure is a PLMN selection procedure in the 3GPP23.122 protocol. If the MCC of the HPLMN is 460, and it is determined that the air interface MCC list includes only the foreign MCC, it is determined that the mobile terminal is in the international roaming network outside the continental china, and because the network outside the continental china does not support the TDSCDMA system, the network selection residence of the TDSCDMA system PLMN network is not performed, thereby increasing the network selection speed. When the mobile terminal moves in the environment of the foreign network, the network selection is realized rapidly by the network selection in the PLMN of the foreign network support system.

Fig. 4 shows a block diagram of a first embodiment of a network selection system of a foreign roaming boundary provided by the present invention. A network selection system of the foreign roaming boundary of the embodiment is mainly executed by the mobile terminal. The system comprises an acquisition unit 41, a first MCC detection unit 42 and a determination unit 43.

An obtaining unit 41, configured to obtain an air interface MCC list according to PLMN information obtained from the air interface. Specifically, the mobile terminal extracts the MCC from the PLMN information acquired by the air interface, and stores the MCC into the mobile terminal to obtain a list of MCCs of the air interface.

The first MCC detecting unit 42 is configured to determine that the air interface MCC list includes the local MCC and the foreign MCC.

A determining unit 43, configured to determine whether the MCC of the currently residing first PLMN network is the same as the local MCC, if so, register the first PLMN network, otherwise, filter the non-local MCC in the empty MCC list, select to reside in the second PLMN network in the PLMN network corresponding to the filtered empty MCC list, and register the second PLMN network.

In summary, the embodiment realizes that the mobile terminal preferentially resides in the appropriate home PLMN network under the condition of cross coexistence of the home network and the foreign roaming network, which effectively saves the user cost, and effectively improves the network selection speed due to the filtering of the foreign PLMN network.

Fig. 5 is a block diagram illustrating a second embodiment of a network selection system for a foreign roaming boundary according to the present invention. The difference between this embodiment and the first embodiment of the network selection system of the foreign roaming boundary is that: the obtaining unit may further shorten or prolong a period of obtaining PLMN information from the air interface according to a change of the air interface MCC list, which may effectively reduce power consumption of the mobile terminal. The system comprises an acquisition unit 51, a first MCC detection unit 52 and a determination unit 53.

An obtaining unit 51, configured to obtain an air interface MCC list according to PLMN information obtained from the air interface.

The obtaining unit 51 in this embodiment is specifically configured to: the method comprises the steps of obtaining an air interface MCC list according to PLMN information periodically acquired from an air interface, wherein the period in the periodic acquisition process can be fixed or unfixed, the step can be realized by periodically updating a timer, and the initial duration of the step is a minimum period threshold Tmin.

Specifically, a minimum period threshold Tmin and a maximum period threshold Tmax are preset, an acquired air interface MCC list a1 is obtained according to currently acquired PLMN information, whether the air interface MCC list a1 is consistent with a pre-acquired air interface MCC list a2 is judged, if yes, the current period T0 is reduced to a first period T1, and the first period T1 is greater than or equal to the preset minimum period threshold Tmin; if not, the current period T0 is extended to a second period T2, the second period T2 is less than or equal to a preset maximum period threshold Tmax, and the empty MCC list a1 is the current MCC list. The air interface MCC list a1 is obtained periodically from an air interface according to a period T0 or obtained by triggering a background network search through other programs, the pre-obtained air interface MCC list a2 is an MCC list obtained before obtaining the current MCC list, and may be a most adjacent MCC list updated last time before obtaining the current MCC list, and the air interface MCC list a2 may be obtained through PLMN information periodically obtained from the air interface, or may be obtained by triggering and reading a cell broadcast message through other programs in the mobile terminal.

The update procedure of the air interface MCC list in the obtaining unit 51 is further explained by the following example:

a: the obtaining unit 51 updates the air interface MCC list by periodically updating the timer, and the initial duration of the obtaining unit is the minimum value T;

b: after the periodic update timer is overtime, the obtaining unit 51 obtains MCC information of an air interface in a background network searching manner, and the radio resource management module/physical layer tries to read a signal cell broadcast message to obtain PLMN information of the air interface;

c: the obtaining unit 51 records air interface MCC information detected in the background network search of the current round through a radio resource management module, where the radio resource management module is used to execute a preset PLMN selection process;

d: the obtaining unit 51 checks whether the background web searching process is finished: checking whether all the standard frequency points try to acquire empty PLMN (public land mobile network), if the process is not finished, executing C next to acquire PLMN information of the next frequency point; if the network searching process of the current round is finished, executing E, and further checking whether the background network searching of the current round detects a new MCC;

e: after the network searching is completed in the current round, the wireless resource management module notifies the detected air interface MCC information to the network selection control module, and the network selection control module checks whether a new MCC is detected. The obtaining unit 51 detects a new MCC when the mobile terminal normally selects a network, reselects or recovers coverage, and then updates and checks the maintained empty MCC list. If a new MCC is detected, G is executed next, and the obtaining unit 51 updates an air interface MCC list stored in the mobile terminal; otherwise, indicating that no new MCC is detected, then executing step F, and changing the time length of the timer retrieved by the air interface MCC;

G: the air interface PLMN search detects a new MCC, the obtaining unit 51 updates the MCC list stored in the mobile terminal, and meanwhile, the time length of the timer for the air interface MCC periodic retrieval is reset or shortened. When a new MCC is detected, the time length of the reset timer is the initial minimum value, so that the network environment of the mobile terminal can be determined as soon as possible in a short time.

The first MCC detecting unit 52 is configured to determine that the air interface MCC list includes the local MCC and the foreign MCC. The first MCC detection unit 52 is implemented in the same way as the first MCC detection unit 42 of the first embodiment of the network selection system of the foreign roaming boundary.

A determining unit 53, configured to determine whether the MCC of the currently residing first PLMN network is the same as the local MCC, if so, register the first PLMN network, otherwise, filter the non-local MCC in the empty MCC list, select to reside in the second PLMN network in the PLMN network corresponding to the filtered empty MCC list, and register the second PLMN network. The function of the judging unit 53 is the same as that of the judging unit 43 of the first embodiment of the network selection system of the foreign roaming boundary.

Fig. 6 shows a block diagram of a third embodiment of a network selection system of a foreign roaming boundary provided by the present invention. The difference between this embodiment and a second embodiment of a network selection system at a foreign roaming boundary is that a first MCC detecting unit 61 and a second MCC detecting unit 62 are added, and a network selection process in a PLMN network after a mobile terminal moves to a non-cross network environment changes to implement fast network selection, and the system is added with a second determining unit 61 and a third determining unit 62 on the basis of the second embodiment.

And a second MCC detecting unit 61, connected to the obtaining unit 51, configured to determine that the MCC list in the air interface includes only the local MCC, and select to reside in a third PLMN network in a network system supported by a local area of an operator through a preset PLMN selection procedure, so as to register the third PLMN network.

Specifically, the second MCC detecting unit 61 compares the MCC of the HPLMN in the phone card with each MCC in the empty MCC list one by one, and if it is determined that the empty MCC list includes only the local MCC, selects to reside the third PLMN network in the network system supported by the local area of the operator in the empty via the preset protocol selection flow, and registers the third PLMN network. For example, the preset PLMN selection procedure is a PLMN selection procedure in the 3GPP23.122 protocol. When the mobile terminal moves in the local network environment, the network is selected in the network system supported by the local area of the operator so as to realize quick network selection. For example, by combining the MCC and the SIM/USIM card, if it is detected that the local MCC is 460, that is, in china, the PLMN is 46000, which is a mobile card, only the system supported by the china mobile in china is searched, and the WCDMA system is not searched.

And a third MCC detecting unit 62, connected to the obtaining unit 51, configured to determine that the air interface MCC list includes only an alien MCC, and select to reside in a fourth PLMN network in a network system supported by an operator foreign area through a preset PLMN selection procedure, so as to register the fourth PLMN network.

Specifically, the third MCC detecting unit 62 compares the MCC of the HPLMN in the phone card with each MCC in the air interface MCC list one by one, and if it is determined that the air interface MCC list includes only an alien MCC, selects to reside the fourth PLMN network in the network system supported by the operator alien region in the air interface through a preset PLMN selection process, and registers the fourth PLMN network. For example, the preset PLMN selection procedure is a PLMN selection procedure in the 3GPP23.122 protocol. If the MCC of the HPLMN is 460, and it is determined that the air interface MCC list includes only the foreign MCC, it is determined that the mobile terminal is in the international roaming network outside the continental china, and because the network outside the continental china does not support the TDSCDMA system, the network selection residence of the TDSCDMA system PLMN network is not performed, thereby increasing the network selection speed. When the mobile terminal moves in the environment of the foreign network, the network selection is realized rapidly by the network selection in the PLMN of the foreign network support system.

In summary, the network selection method and system for the foreign roaming boundary provided by the present invention implement that the mobile terminal preferentially resides in the appropriate home PLMN network under the condition that the home network and the foreign roaming network coexist crosswise, so that the user cost can be effectively saved and the network selection speed is improved.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims

1. A network selection method for a foreign roaming boundary, comprising:

obtaining an air interface MCC list according to PLMN information periodically obtained from an air interface, wherein, whether the air interface MCC list is consistent with a pre-obtained air interface MCC list or not is judged, if not, the period is reduced to a first period, and the first period is more than or equal to a preset minimum period threshold value; if yes, prolonging the period to a second period, wherein the second period is less than or equal to a preset maximum period threshold value;

2. The method of claim 1, wherein the obtaining of the air interface MCC list according to the PLMN information acquired from the air interface specifically comprises:

3. The method of claim 1, wherein after obtaining the air interface MCC list according to the PLMN information acquired from the air interface, the method further comprises:

4. The method of claim 1, wherein after obtaining the air interface MCC list according to the PLMN information acquired from the air interface, the method further comprises:

5. A network selection system for a foreign roaming boundary, comprising:

an obtaining unit, configured to obtain an air interface MCC list according to PLMN information periodically obtained from an air interface, where whether the air interface MCC list is consistent with a pre-obtained air interface MCC list is judged, and if not, a cycle is reduced to a first cycle, where the first cycle is greater than or equal to a preset minimum cycle threshold; if yes, prolonging the period to a second period, wherein the second period is less than or equal to a preset maximum period threshold value;

6. The system of claim 5, wherein the determining unit is to: judging whether the MCC of the first PLMN network which resides currently is the same as the local MCC, if so, registering the first PLMN network, if not, filtering the foreign MCC in the air interface MCC list, selecting to reside a second PLMN network in the PLMN network corresponding to the filtered air interface MCC list, and registering the second PLMN network.

7. The system of claim 5, wherein the obtaining unit is specifically configured to:

8. The system of claim 5, further comprising a second MCC detecting unit, connected to the obtaining unit, configured to determine that the air interface MCC list includes only a local MCC, and select to camp on a third PLMN network in a network format supported by a local area of an operator through a preset protocol selection procedure, so as to register the third PLMN network.

9. The system of claim 5, further comprising a third MCC detecting unit, connected to the obtaining unit, configured to determine that the air interface MCC list includes only a foreign MCC, and select to camp on a fourth PLMN network in a network standard supported by a foreign area of an operator through a preset protocol selection procedure, so as to register the fourth PLMN network.