CN100421504C - A method for storing mobile station information and a method for positioning the mobile station - Google Patents

Abstract

The invention discloses a method for storing information of a mobile station, which is applied to a communication system including a first mobile switching center and a second mobile switching center. The center sends an inter-office handover request; the second mobile switching center analyzes the aforementioned inter-office handover request to obtain mobile station information; the second mobile switching center stores the aforementioned mobile station information. The invention also discloses a mobile station positioning method. When an inter-office handover occurs, the second mobile switching center saves the mobile station information; the initial mobile switching center starts the positioning process; the positioning service entity requests the second mobile switching center to return the mobile station information; the second mobile switching center returns the aforementioned mobile station information to the positioning service entity; the positioning service entity returns the location service information to the second mobile switching center.

Description

A method for storing mobile station information and a method for positioning the mobile station

technical field

The invention relates to a method for storing network information and a location service in the communication field, in particular to a method for storing information of a mobile station and a method for positioning the mobile station.

Background technique

With the development of the mobile communication industry, business innovation has become the fundamental driving force for the development of networks and technologies. At present, the voice service is still the main body of the mobile communication service, and various new mobile value-added services and mobile data services are the strong economic growth points of the mobile communication market. Among them, services related to user location have developed rapidly.

Location-based services, also known as mobile location services or positioning services, mean that the mobile network obtains the geographic location information (latitude and longitude coordinates) of the mobile terminal through a specific positioning technology, provides it to the mobile station, communication system or a third party, and uses a certain The support of electronic map information provides mobile stations with calling or non-calling services related to their locations. The initial application of the mobile location service is the 911 emergency call in the United States. The national security network can quickly and accurately resolve emergencies such as social security and emergency rescue by locating the location of the calling user. After that, the location business gradually developed and improved, and can be applied to other non-public safety services, such as vehicle dispatching, location query, child monitoring, location billing, travel services, etc., and the protocol system is also becoming more and more perfect.

Enhanced wireless 911 phase two agreement: "J-STD-036-AD-2" agreement defines the positioning process after the mobile station dials the 911 number. The mobile station information is stored in the VLR (Visitor Location Register, Visitor Location Register) of the MSC (Mobile Switch Center, mobile switching center). When a mobile station initiates or receives a call, the MSC that first establishes a traffic channel is called AMSC (Anchor MSC, initial mobile switching center). During the calling process, if the mobile station moves and arrives within the range of another MSC, the mobile station can switch to the service channel of the new MSC. This new MSC is called SMSC (Serving MSC, serving mobile switching center). The switching of MSC during the calling process is called interoffice switching. In the location service, the AMSC notifies the entities related to the location service to initiate the location acquisition procedure. Entities related to location services include MPC (Mobile Location Center), PDE (Position Decision Entity), etc., and perform location services during the conversation of the mobile station. In the location acquisition process, the MPC or PDE queries the relevant data of the mobile station from the MSC, and the MSC returns the mobile station information stored in the VLR to the entity related to the location service. The map and other information converted from the location information is returned to the mobile station. Since the VLR is indexed with the mobile station identity (IMSI (International Mobile Subscriber Identity) or ESN (Electronic Serial Number, electronic serial number), MIN (Mobile Identification Number, mobile identification number)), the VLR can be directly based on The mobile station ID fetches the mobile station information.

During the calling process of the prior art, the information of the mobile station is always stored in the VLR of the AMSC, and the information of the mobile station is not stored in the VLR of the SMSC. The subscriber identity (IMSI, ESN or MIN) obtains the mobile station information from the VLR of the AMSC.

However, there are defects in the existing technology. As shown in Figure 1, after the mobile station is handed over between offices, the AMSC first sends an inter-office handover request to the SMSC, and the SMSC does not store the mobile station information carried in the inter-office handover request. After the handover is completed, the MPC Or when the PDE inquires the relevant information of the mobile station from the SMSC, there is no information content that can be provided in the SMSC, so the entity related to the positioning service cannot obtain or obtain the information of the mobile station in a timely manner, so that the positioning fails or increases the processing time of the positioning, and finally leads to failure to obtain or The exact location of the mobile station (latitude and longitude, altitude, time and other information) cannot be obtained in time.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for storing mobile station information, so that the mobile station can store the mobile station information in the serving mobile switching center when the mobile station is handed over between offices.

Another technical problem to be solved by the present invention is to provide a mobile station positioning method, so that the positioning service entity can successfully obtain the mobile station information from the serving mobile switching center when the mobile station is handed over between offices.

In order to solve the above-mentioned technical problems, the present invention provides a method for storing mobile station information, which is applied to a communication system including a first mobile switching center and a second mobile switching center, and is characterized in that it includes steps:

1) The first mobile switching center sends an inter-office handover request to the second mobile switching center;

2) The second mobile switching center analyzes the aforementioned inter-office handover request to obtain mobile station information;

3) The second mobile switching center saves the aforementioned mobile station information, and returns an inter-office handover request response to the first mobile switching center.

Wherein, in the step 3), the second mobile switching center stores the information of the mobile station in the visitor location register.

Wherein, a database may also be added in the second mobile switching center, and the mobile station information is saved in the database in the step 3) to save the mobile station information.

The present invention also includes the following steps:

The second mobile switching center refreshes the saved mobile station information.

When the call is released, the mobile station information of the second mobile switching center is deleted.

The deletion of mobile station information can also be completed by selecting the following steps:

1. When the call is released, the mobile station information in the first mobile switching center and the second mobile switching center are deleted together.

2. After the second mobile switching center successfully saves the mobile station information, delete the mobile station information of the first mobile switching center.

The method for positioning a mobile station provided by the present invention is realized based on the above method for storing mobile station information, including steps:

A. The second mobile switching center receives the switching request from the initial mobile switching center and obtains the information of the mobile station;

B. The second mobile switching center saves the mobile station information;

C. The initial mobile switching center starts the positioning process;

D. The positioning service entity requests the second mobile switching center to return the information of the mobile station;

E. The second mobile switching center returns the aforementioned mobile station information to the positioning service entity;

F. The positioning service entity returns the location service information to the second mobile switching center.

Wherein, the step E is specifically realized by the following steps: the second mobile switching center analyzes the request sent by the location service entity; obtains the mobile station information from the visitor location register, and sends it to the location service entity.

The step E can also be implemented by the following steps: the second mobile switching center analyzes the request sent by the location service entity; obtains the mobile station information from the database, and sends it to the location service entity.

Compared with the prior art, the beneficial effect of the present invention is: the present invention provides the process that the serving mobile switching center saves the relevant data of the mobile station when switching between offices, and when the present invention is applied to the location service, it solves the existing problems The problem that the positioning entity cannot obtain the information of the mobile station when switching between technical bureaus.

Since the serving mobile switching center stores the mobile station information in the VLR, and the VLR is a database indexed by the mobile station ID, and because the request sent by the positioning service entity to the serving mobile switching center contains the mobile station ID, the serving mobile switching center The center can timely return the mobile station information to the location service entity. The serving mobile switching center deletes the stored mobile station information when necessary, thereby avoiding conflicts caused by saving mobile station information in multiple mobile switching centers; in addition, in order to ensure the correctness and validity of the mobile station information, the serving mobile The switching center regularly refreshes the stored relevant information of the mobile station.

Description of drawings

Fig. 1 is the working flow diagram of the location service when switching between offices in the prior art;

Fig. 2 is the flow chart of SMSC storing mobile station information when switching forward according to the present invention;

Fig. 3 is the embodiment of backward switching when the first SMSC of the present invention deletes the mobile station information;

Fig. 4 is an embodiment of mobile station positioning combined with the method for storing mobile station information according to the present invention.

Detailed ways

Mobile station information is stored in the MSC. When a mobile station initiates or receives a call, the MSC that first establishes a traffic channel is called AMSC. During the calling process, if the mobile station moves and arrives within the range of another MSC, the mobile station can switch to the service channel of the new MSC. This new MSC is called SMSC. The switching of MSC during the calling process is called interoffice switching. The handover of the mobile station from the current MSC to the new MSC is called forward handover; the process of handover of the mobile station from the current MSC to the new MSC and then back to the original MSC is called backward handover.

The present invention provides a solution for storing the information of the mobile station in the serving mobile switching center when the mobile station is handed over between offices.

The following is a detailed introduction to forward switching and backward switching:

When the mobile station is handed over for the first time, the method for storing the information of the mobile station provided by the present invention is that the initial mobile switching center sends an inter-office handover request to the serving mobile switching center, and the request carries the mobile station identification, and the current Cell, mobile station positioning capability, air interface parameters and other mobile station information related to positioning; the serving mobile switching center will send the inter-office handover request response to the initial mobile switching center after saving the aforementioned mobile station information; after the incoming handover is completed, if the mobile station When an intra-office handover occurs, the serving mobile switching center updates the stored mobile station information; in order to avoid storing mobile station information in multiple mobile switching centers, the serving mobile switching center deletes the mobile station information after the call is released.

Fig. 2 is the embodiment during the above-mentioned forward handover, and the step of storing mobile station information specifically includes:

Step F1, AMSC sends FACDIR2 (Facilities Directive 2 Invoke, forward handover request) to SMSC, requesting to establish a wireless channel in the SMSC area, the request carries the mobile station identification, and the current cell, mobile station positioning capability, air interface parameters and other mobile station information related to positioning;

Step F2, SMSC analyzes the received forward handover request, obtains the aforementioned mobile station information from the forward handover request according to the mobile station identifier, and saves it in the visitor location register VLR;

Step F3, SMSC sends facdir2 (forward switching request response) to AMSC, establishes a connection between AMSC and SMSC, and incoming switching is completed;

Step F4, since the mobile station information contains the current cell, intra-office handover may occur after the mobile station completes the inter-office handover, so in order to ensure the correctness and validity of the mobile station information, when the SMSC detects that the mobile station information changes Mobile station information is updated;

Step F5, in order to avoid problems such as call conflict caused by storing the mobile station information in multiple MSCs, after the call is released, delete the mobile station information in the SMSC.

In the above step F2, the SMSC can also be implemented by adding a database for storing mobile station information.

When the mobile station has multiple forward handovers, the current SMSC sends a forward handover request to the new SMSC, and the new SMSC analyzes the aforementioned forward handover request and saves the information of the mobile station. The saving process is the same as the storage when the AMSC switches to the SMSC The process is similar and will not be repeated; the same new SMSC can also store mobile station information by adding a database. After the new SMSC stores the mobile station information, in order to ensure that only the mobile station information is saved in the AMSC, the mobile station information in the SMSC can be deleted in the following two ways:

D1: After the current SMSC successfully stores the mobile station information, delete the mobile station information in the previous SMSC;

D2: After the call is released, delete all the mobile station information in the SMSC.

When the mobile station is handed over backwards, the mobile station is handed over from AMSC to SMSC, and then switched back to AMSC from SMSC, since the mobile station information is saved in both SMSC and AMSC during the call process, there is no need to perform mobile station handover during the handover process. Information preservation, in order to ensure the correctness and validity of the mobile station information, it is necessary to update the mobile station information stored in the AMSC.

When the mobile station has multiple forward handovers, if it is executed according to the above D2 method, and the previous SMSC does not delete the mobile station information after the current SMSC saves the mobile station information during the call process, when switching back to the previous SMSC from the current SMSC, The former SMSC only needs to refresh the stored mobile station information according to the information in HANDBACK2 (backward handover request), and does not need to store the mobile station information again.

Fig. 3 is carried out according to above-mentioned D1 method, the embodiment of backward switching when previous SMSC deletes mobile station information, concrete steps include:

Step B1, the current SMSC sends a HANDBACK2 (backward handover request) to the previous SMSC, which carries the mobile station identification, and the current cell, mobile station positioning capability, air interface parameters and other mobile station information related to positioning;

Step B2, the previous SMSC analyzes the received backward handover request, obtains the aforementioned mobile station information from the forward handover request according to the mobile station identifier, and stores it in the request in the visitor location register VLR;

Step B3, the previous SMSC sends a backward switching request response to the current SMSC, and the incoming switching is completed;

Step B4, since the mobile station information contains the current cell, intra-office handover may occur after the mobile station completes the inter-office handover, so in order to ensure the correctness and validity of the mobile station information, when the SMSC detects that the mobile station information changes Mobile station information is updated;

Step B5, in order to avoid problems such as call conflict caused by storing the mobile station information in multiple MSCs, delete the mobile station information in the SMSC, and the deletion method can be performed according to the above-mentioned D1 and D2.

Combining the specific embodiments of the above-mentioned forward handover and backward handover, the method for storing mobile station information provided by the present invention is that when an interoffice handover occurs in a mobile station, the first mobile switching center sends an interoffice handoff to the second mobile switching center. request; the second mobile switching center parses the aforementioned inter-office handover request to obtain mobile station information; the second mobile switching center stores the aforementioned mobile station information. The first mobile switching center is the above-mentioned AMSC when the first forward handover occurs, and the second mobile switching center is the above-mentioned SMSC; when multiple forward handovers occur, the first mobile switching center is the above-mentioned current SMSC, and the second mobile switching center The switching center is the previous SMSC mentioned above. Since the mobile station may undergo an intra-office handover after an inter-office handover, the mobile station information is updated after each handover; in addition, in order to ensure that the mobile station information is only saved in the AMSC, the mobile station information in the SMSC must be deleted , the deletion time may be after the call is released, or after the second mobile switching center successfully saves the information of the mobile station.

The present invention also provides a method for applying the above-mentioned method for storing mobile station information to a method for mobile station positioning. The following describes the embodiment of mobile station positioning in detail with reference to FIG. 4 and in combination with the above-mentioned method for storing mobile station information.

After the inter-office handover of the mobile station, the serving mobile switching center saves the mobile station information; if the initial mobile switching center detects that the mobile station has a location service, it starts the positioning process; the entity related to the positioning service requests the serving mobile switching center to return the mobile station information , the request carries the mobile station ID; the serving mobile switching center returns the saved mobile station information to the entity related to the positioning service according to the ID of the mobile station; the entity related to the positioning service calculates the position of the mobile station according to the relevant information of the mobile station; The entity returns location information (coordinates, etc.) to the serving mobile switching center.

Specific steps include:

Step P1, the serving mobile switching center saves the information of the mobile station;

Step P2, the initial mobile switching center judges whether the location service occurs in the mobile station, if so, the initial mobile switching center sends an ISPOSREQFWD message (IntersystemPositionRequestForward, forward inter-office position request) to the serving mobile switching center, which includes the mobile station identification, position Location-related mobile station information such as request type and mobile station location capability;

Step P3, the serving mobile switching center then sends an ISPOSREQ (IntersystemPositionRequest, inter-office position request) to the MPC, including the mobile station identification and the mobile station positioning capability (such as whether to support GPS positioning), the current cell, etc. information;

Step P4, MPC constructs parameters such as the aforementioned call origination request, mobile station identification, service mobile switching center identification, location request type (such as carrying out GPS positioning) into GPOSREQ (GeoPositionRequest, geographic location request) and sends it to the selected PDE, indicating The PDE obtains the location information of the mobile station;

Step P5, PDE constructs SMDPP (SMSDeliveryPointToPoint, short message point-to-point delivery) message after receiving the aforementioned geographic location request, and the GPS positioning parameters (such as GPS satellite measurement parameters) required for measurement by the mobile station identification and the mobile station are passed through the service The mobile switching center and the base station controller transmit it to the mobile station, and wait for the mobile station to return relevant measurement information and data for position calculation;

Step P6, the mobile station returns smdpp (short message point-to-point delivery response) to the PDE, with GPS measurement results (distance to 4 satellites, etc.), current cell (obtained from the target mobile switching center), air interface parameters (from obtained from the target mobile switching center) and return to the PDE;

Step P7, PDE returns gposreq (geographical location request response) to MPC, sends positioning result (success/failure), positioning location information to MPC;

In step P8, the MPC returns an isposreq message (inter-office handover request response) to the serving MSC, and returns the location information to the serving MSC.

The above step P1 can be executed according to the aforementioned method for storing mobile station information.

The serving mobile switching center in the above embodiments can be replaced by the first SMSC and the second SMSC correspondingly according to the actual situation.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications should also be It is regarded as the protection scope of the present invention.

Claims (10)

1. A method for storing mobile station information, applied to the communication system comprising the first mobile switching center and the second mobile switching center, is characterized in that, comprising steps: 1) The first mobile switching center sends an inter-office handover request to the second mobile switching center; 2) The second mobile switching center analyzes the aforementioned inter-office handover request to obtain mobile station information; 3) The second mobile switching center saves the aforementioned mobile station information, and returns an inter-office handover request response to the first mobile switching center. 2. The method for storing mobile station information according to claim 1, characterized in that: in the step 3), the second mobile switching center stores the mobile station information in the visitor location register. 3. The method for storing mobile station information according to claim 1, further comprising: adding a database at the second mobile switching center, and in said step 3), the mobile station information is saved to said database. 4. The method for storing mobile station information according to claim 1, 2 or 3, further comprising: the second mobile switching center refreshes the stored mobile station information. 5. The method for storing mobile station information according to claim 4, further comprising: deleting the mobile station information of the second mobile switching center when the call is released. 6. The method for storing mobile station information according to claim 4, further comprising: deleting the mobile station information in the first mobile switching center and the second mobile switching center together when the call is released. 7. The method for storing mobile station information according to claim 4, further comprising: after the second mobile switching center successfully saves the mobile station information, deleting the mobile station information of the first mobile switching center. 8. A method for mobile station positioning, characterized in that it comprises steps: A. The second mobile switching center receives the switching request from the initial mobile switching center and obtains the information of the mobile station; B. The second mobile switching center saves the mobile station information; C. The initial mobile switching center starts the positioning process; D. The positioning service entity requests the second mobile switching center to return the information of the mobile station; E. The second mobile switching center returns the aforementioned mobile station information to the positioning service entity; F. The positioning service entity returns the location service information to the second mobile switching center. 9. The method for a kind of mobile station location according to claim 8, it is characterized in that, described step E specifically comprises: the request that the second mobile switching center resolves aforementioned positioning service entity to send; Obtain aforementioned mobile station from visitor location register The information is sent to the positioning business entity. 10. A kind of mobile station location method according to claim 8, is characterized in that: described step E specifically comprises: the second mobile switching center analyzes the request that aforementioned positioning service entity sends; Obtain aforementioned mobile station information from database, Sent to the positioning business entity.

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