CN1988720A - Selecting method for communication network - Google Patents

Abstract

A method for selecting a communication network, comprising the steps: the mobile phone receives parameters from the current network and/or a home network that has overlapping coverage areas with the current network; the mobile phone performs related operations with the current network and/or the home network; the mobile phone according to the Parameters to determine whether to give priority to the home network for access attempts. According to the method of the present invention, when the mobile phone roams to the border area bordering on the home network and other networks, it can preferentially select its home network instead of other networks. According to the invention, the user may avoid expensive roaming or even international roaming charges; the operator who the user subscribes to may also save considerable settlement charges.

Description

How to choose a communication network

technical field

The present invention relates to the communication field, in particular, to a method for selecting a communication system network.

Background technique

Whenever the mobile phone is turned on or the user moves to a new registration area, the mobile phone will initiate a Public Land Mobile Network (hereinafter referred to as PLMN) discovery process. Usually, the mobile phone moves within the service range of its home PLMN (hereinafter referred to as HPLMN), and receives the service of its HPLMN. This HPLMN is usually the PLMN owned by the service provider contracted with the user.

Generally speaking, after signing a contract with a service provider, each subscriber will obtain a code that is used to uniquely identify the user—the International Mobile Station Identity (hereinafter referred to as IMSI), which is usually stored in a small inside the SIM card. This SIM card can be inserted into the mobile phone and can be used to identify the user's code when needed. Referring to Figure 1, the IMSI includes a mobile country number (hereinafter referred to as MCC), a mobile network number (hereinafter referred to as MNC) and a customer identification code field (hereinafter referred to as MSIN), which are used to indicate which country the user belongs to and which country the user belongs to. A mobile network and which user is on the mobile network. The mobile phone knows whether a PLMN is an HPLMN by comparing a PLMN's mobile country code (hereinafter referred to as MCC) and mobile network number (hereinafter referred to as MNC) fields with the IMSI's MCC/MNC field. If the mobile phone cannot establish a connection with the HPLMN, it must search and connect to another different PLMN, that is, a visited PLMN (hereinafter referred to as VPLMN). This usually happens when a mobile phone roams into an area where its HPLMN cannot provide coverage.

When the mobile phone selects a suitable PLMN, it will search for and select a suitable cell of the PLMN that can provide cellular services. Then the mobile phone will tune to the control channel of the selected cell, and register with the network that its current location exists in the registration area to which the selected cell belongs. Later, when communication needs to be initiated (such as making a call), the mobile phone accesses the network through the control channel of the selected cell. Sometimes the mobile phone will periodically continue to search for a more suitable cell in the selected PLMN. This situation sometimes happens, for example, the mobile phone moves out of the service range of the selected cell and loses the coverage of the selected cell.

Sometimes, a specific area may be covered by more than one PLMN, that is, there is overlap of PLMN service areas. At this time, the mobile phone needs to select a specific PLMN from these existing PLMNs at the beginning, instead of selecting other PLMNs. In addition, for example, in the case of roaming, the mobile phone may lose the coverage of the selected PLMN. At this time, the mobile phone must select another PLMN network to provide services. The operation of selecting a specific PLMN can be performed automatically or manually. Automatic selection uses a list of PLMNs arranged according to priority, from which the mobile phone selects the top PLMN that exists in turn. Manual selection is to provide the user with a list of existing PLMNs from which the user must select a PLMN.

Currently, the list of available PLMNs and their priorities are determined by which network provides the strongest signal or the strongest radio frequency (hereinafter referred to as RF). For example, if the provider of the first PLMN provides a stronger signal than the provider of the second PLMN, the phone ranks the first PLMN higher than the second PLMN in the list, so that if If the phone uses auto-select, then the first PLMN will be automatically selected based on its signal strength. If a VPLMN is selected, the handset may continue to periodically look for its HPLMN. For a more detailed description of the current PLMN selection, please refer to "Universal MobileTelecommunications System (UMTS) Non-Access-Stratum functions related to Mobile Station (MS) in idle mode," 3GPP TS 23.122, V.4.1.0, Release 4, European Telecommunications Standards Institute (2001).

Regardless of whether it is automatic selection or manual selection, the PLMN selection process usually takes a long time, and it usually takes several minutes to tens of minutes depending on the specific situation. At present, in order to speed up the selection of PLMN, when the mobile phone is turned on or the user moves to a new registration area, the mobile phone will first try to contact the last selected PLMN. If the PLMN does not exist, the mobile phone starts the process of automatically or manually selecting the PLMN.

With the improvement of people's living standards and the development of mobile communications, there are more and more situations where users roam to other places, including the situation where users roam to border areas bordering HPLMN and other PLMNs. At this time, for these users, if they have selected other PLMNs before, then when they turn on the phone again or move from other registration areas to these border areas, the mobile phones will also preferentially select other previous PLMNs. In this way, even if there is HPLMN coverage in these areas, the mobile phones of these users will bring expensive roaming or even international roaming charges to these users because they choose other PLMNs. From the point of view of the contracted operators of these users, they are also willing for these users to choose HPLMN instead of other PLMNs, so as to avoid paying corresponding settlement fees to the contracted users because they use the network of other PLMNs.

Contents of the invention

Therefore, the purpose of the present invention is to propose a method for a mobile phone to select a PLMN, so that the mobile phone can preferentially select the HPLMN instead of other PLMNs when it roams to the border area bordering the HPLMN and other PLMNs.

In order to achieve the above purpose, a method for selecting a communication network includes the steps of:

a) The handset receives parameters from the current network and/or a home network with mutually overlapping coverage areas with the current network;

b) The mobile phone performs related operations with the current network and/or home network;

c) The mobile phone decides whether to preferentially select the home network to try to access according to the parameters.

According to the method of the present invention, when the mobile phone roams to the border area bordering on the home network and other networks, it can preferentially select its home network instead of other networks. According to the present invention, the user may avoid expensive roaming or even international roaming charges; the operator the user subscribes to may also save considerable settlement charges.

Description of drawings

Figure 1 is a block diagram of the components of the IMSI;

Figure 2 is a block diagram representing a wireless communication system that may be used in the preferred embodiment of the present invention;

Figure 3 is a block diagram representing multiple PLMNs with overlapping service areas;

FIG. 4 is a flowchart describing the steps performed for PLMN selection according to the first embodiment of the present invention;

FIG. 5 is a flowchart describing the steps performed for PLMN selection according to a second embodiment of the present invention;

Fig. 6 is a flowchart describing the steps performed for PLMN selection according to a third embodiment of the present invention.

Detailed ways

The invention relates to a method for a mobile phone to select a communication network. The invention provides a communication network selection method suitable for mobile phones, so that the mobile phone can preferentially select its home network instead of other networks when it roams to the border area bordering the home network and other networks. When the mobile phone accesses a certain network last time, the said network or other networks provide a parameter to the mobile phone. When the mobile phone needs to select a network, it determines whether to preferentially select its home network according to the parameters.

Referring to the accompanying drawings, three preferred embodiments of the communication system according to the present invention are described below. In particular, the communication system is a wireless communication system operating in compliance with at least one of the following communication standards. These standards include various analog, digital or analog/digital dual-mode communication system protocols, such as but not limited to Advanced Mobile Phone System (AMPS for short), Narrowband Advanced Mobile Phone Service (NAMPS for short), Global System for Mobile Communications (referred to as GSM), High Data Rate GSM Evolution (referred to as EDGE), General Packet Radio Service (referred to as GPRS), Universal Mobile Telecommunications System (referred to as UMTS), Frequency Division Multiple Access (referred to as FDMA), IS-55 Time Division Multiple Access ( TDMA for short) digital cellular, IS-136 TDMA digital cellular, IS-95 Code Division Multiple Access (CDMA for short) digital cellular, distribution on demand (DA/TDMA, DA/CDMA, DA/FDMA), broadband code division Multiple access (referred to as WCDMA), CDMA 2000, IMT-2000, personal wireless communication system (referred to as PCS/PHS), 3GPP, 3GPP2 and various deformations and evolutions of these protocols. The communication system described in the present invention may further refer to all communication network systems as described below. A node in these communication network systems needs to distinguish different users. For example, the communication network system identifies that a user who needs to access the network belongs to the contract A local user of the network is still a roaming user roaming to this network; or a different network, for example, when a user accesses a communication network system, it needs to identify whether the network to be accessed is the subscribed home network or the visited network. This may include a local area network (hereinafter referred to as LAN), a wireless local area network (hereinafter referred to as WLAN), and the like. In order to avoid making the description of this patent too lengthy, in the following description, detailed descriptions of functions or devices that are well known to the public are omitted.

Referring to FIG. 2 , a wireless communication system 200 includes a communication backbone network 210 , a group of base station controllers (hereinafter referred to as BSCs) 220 and 222 , and they jointly provide services in a service area 230 . Typically, the BSC handles encryption/decryption of signals, handover decisions, and access decisions. The wireless communication system 200 may be, but not limited to, an FDMA-based communication system, a TDMA-based communication system, or a CDMA-based communication system. As these systems are known, each BSC 220 and 222 and one or more base transceiver stations (hereinafter referred to as BTS) 240, 242, 244 and 246 associated with it, each communication cell 250 in the entire service area 230 , 252, 254 and 256 provide services. For ease of explanation, the BSC and BTS are described from the perspective of the invention. But, this is not equal to that invention is only limited to BSC and BTS; Because radio network controller (hereinafter referred to as RNC), base station (abbreviated as Node B) and other similar technologies can also be used to realize the present invention, this is to those skilled in the art To a technical person, it is very obvious. BSC220 and 222, and BTS240, 242, 244 and 246 comply with practical and feasible standards, and provide wireless communication services for mobile phones (hereinafter referred to as MS) 260, 262, 264, 266 working in communication cells 250, 252, 254 and 256 . Each of the system components mentioned above is commercially available, such as from Motorola.

Referring to FIG. 3, multiple PLMNs 302, 304 have service areas that overlap with each other. Each PLMN 302, 304 can be set up like the wireless communication system 200 in FIG. 2 . For ease of illustration, each PLMN 302, 304 is represented by several communication cells 302a-c, 304a-c. But actually, each PLMN usually has a lot of network cells, with several BTSs and several BSCs. The handset 310 as shown in FIG. 2 is located within the overlapping cells 302a, 304a and thus is located with coverage of the PLMNs 302, 304 at the same time. The handset 310 needs to find available PLMNs and select an appropriate one to serve the communication process it will use (eg, voice communication, real-time video communication, text messaging, Internet access, etc.). In the process of finding a suitable PLMN, the handset 310 may consider each PLMN 302, 304 as a possible communication network for it.

For the handset 310, each PLMN 302, 304 may have different characteristics. For example, PLMN 302 is the contracted home PLMN of mobile phone 310 , and PLMN 304 is a visiting PLMN for mobile phone 310 . In this way, even if the mobile phone 310 performs the same communication process, it may need to pay different fees when it selects the PLMN302 or the PLMN304.

First real-time example

In this embodiment, the mobile phone has selected and accessed a network PLMN1 in an automatic or manual manner according to the method described in the present invention or other feasible methods, and accepted the service of PLMN1. Fig. 4 shows the working flowchart of each component of the communication system according to the first embodiment of the present invention. The HPLMN described in Fig. 4 is the home PLMN of the mobile phone. In step 401, the mobile phone accesses the PLMN1 system and accepts the service of the PLMN1. During the above access process, PLMN1 may need to exchange information with the mobile phone HPLMN, for example, authenticate and authenticate the mobile phone.

In step 402, the HPLMN provides a parameter to the mobile phone. In this embodiment, this parameter gives a binary value indicating whether the service area of PLMN1 and the service area of HPLMN overlap with each other. The step 402 can also be performed in the process of the above step 401.

In step 403, the mobile phone, the PLMN1 system, and the HPLMN perform related operations according to current practical and feasible standards, such as performing wireless communication services.

In step 404, the mobile phone needs to select a PLMN again, for example, the mobile phone is turned off again after being turned off, or the PLMN is reselected periodically.

In step 405, the mobile phone decides whether to preferentially select HPLMN to try to access according to the parameters in step 402. In this embodiment, if the binary value parameter is "yes", then the mobile phone preferentially selects HPLMN to try to access. Otherwise, the mobile phone selects a suitable PLMN to try to access according to the existing technology.

Second real-time example

In this embodiment, the mobile phone has selected and accessed a network PLMN1 in an automatic or manual manner according to the method described in the present invention or other feasible methods, and accepted the service of PLMN1. Fig. 5 shows the working flowchart of each component of the communication system according to the second embodiment of the present invention. The HPLMN described in Fig. 5 is the home PLMN of the mobile phone.

In step 501, the mobile phone accesses the PLMN1 system and accepts the service of PLMN1. During the above access process, PLMN1 may need to exchange information with the mobile phone HPLMN, for example, authenticate and authenticate the mobile phone.

Step 502, PLMN1 provides a parameter to the mobile phone. In this embodiment, this parameter is a list of PLMNs whose service areas overlap with the HPLMN service area. The step 502 can also be performed in the process of the above step 501 .

Step 503 , the mobile phone, the PLMN1 system, and the HPLMN perform related operations according to current practical and feasible standards, such as performing wireless communication services.

In step 504, the mobile phone needs to select a PLMN again, for example, the mobile phone is turned off again after being turned off, or the PLMN is reselected periodically.

Step 505, the mobile phone decides whether to preferentially select HPLMN to try to access according to the parameters in step 502. In this embodiment, if there is PLMN1 in the PLMN list, the mobile phone preferentially selects HPLMN to try to access. Otherwise, the mobile phone selects a suitable PLMN to try to access according to the existing technology.

The third real-time example

In this embodiment, the mobile phone has selected and accessed a network PLMN1 in an automatic or manual manner according to the method described in the present invention or other feasible methods, and accepted the service of PLMN1. FIG. 6 shows the working flowchart of each component of the communication system according to the third embodiment of the present invention. The HPLMN described in Fig. 6 is the home PLMN of the mobile phone.

In step 601, the mobile phone accesses the PLMN1 system and accepts the service of the PLMN1. During the above access process, PLMN1 may need to exchange information with the mobile phone HPLMN, for example, authenticate and authenticate the mobile phone.

Step 602, HPLMN provides a parameter to the mobile phone. In this embodiment, this parameter provides a list of geographical areas, in which the mobile phone can be regarded as a communication network that can be used by HPLMN, and can also be regarded as at least one communication network that can be used by other PLMNs. The step 602 can also be performed in the process of the above step 601.

In step 603, the mobile phone, the PLMN1 system, and the HPLMN perform related operations according to current practical and feasible standards, such as performing wireless communication services.

In step 604, the mobile phone needs to select a PLMN again, for example, the mobile phone needs to be turned off again after being turned off, or the PLMN is reselected periodically.

In step 605, the mobile phone decides whether to preferentially select HPLMN for attempted access according to the parameters in step 602 and the current geographic location. In this embodiment, if the current geographic location is within the geographic area list, the mobile phone preferentially selects HPLMN to attempt to access. Otherwise, the mobile phone selects a suitable PLMN to try to access according to the existing technology.

The current geographic location of the mobile phone can be obtained through existing technologies, such as GPS positioning.

Although the invention has been described in terms of the three illustrated examples, it should be noted that these examples are by way of illustration and not limitation of the invention. Those skilled in the art can easily modify, add and delete any steps in these embodiments without departing from the spirit and scope of the present invention.

Claims (7)

1. the system of selection of a communication network comprises step:

A) mobile phone receives and has the parameter of the home network of overlapped overlay area from current network and/or with current network;

B) mobile phone and current network and/or home network carry out associative operation;

C) mobile phone is according to described parameter, and whether decision preferentially selects home network to attempt inserting.

2. method according to claim 1 is characterized in that described parameter is a bi-values.

3. method according to claim 1 is characterized in that described parameter is a PLMN tabulation.

4. method according to claim 1 is characterized in that described parameter is a geographic area tabulation.

5. according to the described method of one of claim 1-4, it is characterized in that described parameter is provided by current network or home network.

6. method according to claim 1, it is characterized in that described step a) also comprises: current network is carried out authentication, authentication to mobile phone.

7. method according to claim 1 is characterized in that the selection in the described step c) comprises: shutdown back mobile phone shuts down or periodic PLMN reselection procedure again.