WO2012048556A1

WO2012048556A1 - Method and mobile communication terminal for accelerating cell search

Info

Publication number: WO2012048556A1
Application number: PCT/CN2011/072100
Authority: WO
Inventors: 郑宏涛
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-10-13
Filing date: 2011-03-24
Publication date: 2012-04-19
Also published as: CN101980571A; CN101980571B

Abstract

A method and mobile communication terminal for accelerating cell search are disclosed by the invention. When a cell frequency point is searched by the terminal, frequency point information used by a current public land mobile network (PLMN) is searched in an operator frequency point information list of the terminal; the searched frequency point information is added to a registered cell list of the terminal; and then an available cell frequency point is searched in the registered cell list. The frequency point information used by the current PLMN is saved in the registered cell list, so an available cell can be quickly searched when the terminal searches the network, therefore the speed for the terminal to capture the network is greatly accelerated, the power consumption of the terminal is also reduced, and the standby time of the terminal is prolonged.

Description

Method for accelerating cell search and mobile communication terminal

The present invention relates to a digital communication method and terminal, and more particularly to a method and a mobile communication terminal for accelerating cell search. Background technique

At present, the process of powering up the terminal and capturing the network from the Out Of Service (00S) area to the signal area is shown in Figure 1:

The non-access stratum (NAS) layer of the terminal protocol stack obtains the current public land mobile telephone network (PLMN) and sends a network request to the access layer (AS) layer of the terminal protocol stack. The NAS checks whether there is an RPLMN (the last registered PLMN) in the terminal, and if not, selects the HPLMN (the home PLMN, which is stored in the SIM/USIM card), and then the NAS sends a Radio Resource Control (RRC) PLMN search request to the AS ( Search REQ) message, requesting the AS to search for available cells of the current PLMN. The RPLMN is stored in a Subscriber Identity Card (SIM) / 3G Subscriber Identity Card (USIM) card.

After receiving the network request from the NAS layer, the AS layer performs full-band scanning on the frequency band supported by the terminal to search for available cells. When searching for a frequency point, the AS first searches for a frequency point registered by the terminal. If an available cell is searched, the AS sends an RRC PLMN search CNF message to the NAS, informing the NAS that a suitable cell has been found. If there is no search or the terminal has no previously registered cell information, the AS layer performs a full-band search according to the frequency band supported by the terminal. This process takes a long time. If an available cell is found, the AS will notify The NAS has found a suitable cell. If not found, the AS will send the currently existing network to the NAS, and the NAS selects an available PLMN according to the priority of the PLMN. The priority order of PLMN is as follows: HPLMN;

User-controlled PLMN-ACT list stored in the SIM card (USER Controlled PLMN Selector with Access Technology);

Operator Controlled PLMN Selector with Access Technology stored in the SIM card;

Randomly select other networks with high signal quality;

Select other networks according to the signal strength from high to low.

According to the current method of capturing a cell, if the user is powered on for the first time or the user moves to the foreign country or the user moves from the OOS area to the signaled area, the terminal does not store the information of the registered network before the shutdown, or the stored network information and the current network information. Inconsistent, the terminal will capture the network for a long time. Moreover, in general, an operator only uses some frequency points in one frequency band, and does not use hundreds of frequency points of the entire frequency band. Therefore, the terminal spends most of the time searching for frequencies that the operator does not use at all. point. Summary of the invention

The object of the present invention is to provide a method for accelerating cell search and a mobile communication terminal, which can better solve the problem that the terminal does not store the information of the pre-shutdown registration network or the stored network information and the current network information are inconsistent when the terminal captures the network time. Long question.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

A method for accelerating cell search, the method comprising the following steps:

A. When the terminal searches for the cell frequency point, the frequency point information used by the current public land mobile telephone network PLMN is searched from the operator frequency point information list stored in the terminal;

B. If the frequency point information used by the current PLMN is found, the frequency information used by the current PLMN is saved to the list of cells registered by the terminal, and the frequency information used by the current PLMN is saved. Search for available cell frequency points in the list of registered cells; otherwise, search for available cell frequency points in the list of registered cells. The step A includes:

The NAS layer of the terminal protocol stack reads the current PLMN stored in the terminal SIM/USIM card; the NAS layer searches for the frequency point information used by the current PLMN from the list of carrier frequency information stored in the terminal.

In the step B, when the frequency point information is found, the process of performing the saving and searching includes:

The NAS layer sends an add request for adding the frequency point information used by the current PLMN to the registered cell list to the AS layer of the terminal protocol stack;

The AS layer responds to the addition request of the NAS layer, clears the frequency point information used by the previously added PLMN in the registered cell list, and saves the frequency point information used by the current PLMN sent by the NAS to the registered cell list;

The NAS layer sends a network request to the AS layer;

The AS layer responds to the network request of the NAS layer, searches for the available cell frequency points from the list of registered cells that store the frequency information used by the current PLMN, and sends the search result to the NAS layer.

And searching for the available cell frequency points from the list of registered cells that store the frequency point information used by the current PLMN, including:

First search for the frequency points registered before the terminal, and then search for the frequency points used by the current PLMN. In the step B, when the frequency point information is not found, the process of performing the search includes:

The NAS layer sends a network request to the AS layer;

The AS layer responds to the network request of the NAS layer, searches for the available cell frequency points from the list of registered cells, and sends the search result to the NAS layer.

The method further includes a process of performing a full-band search when the available cell frequency points are not searched in the list of registered cells, including:

Perform full-band scanning on the frequency bands supported by the terminal to search for available cell frequencies. The method further includes the process of updating a carrier frequency point information list, including: performing a full frequency band search on a frequency band supported by the terminal, and if searching for an available cell frequency point, adding the searched available cell frequency point to the stored terminal In the list of carrier frequency information in the list, to update the list of carrier frequency information;

The terminal reads the frequency point information of the inter-frequency neighboring cell of the current cell from the message sent by the base station, and adds it to the operator frequency point information list stored in the terminal to update the operator frequency point information list.

A mobile communication terminal for accelerating cell search, wherein the terminal is provided with a list of carrier frequency information for storing frequency point information used by the operator, and is also provided with frequency information for storing the registered cell and used by the current PLMN. List of registered cells of frequency information;

The terminal includes:

a control module, configured to search for the frequency point information used by the current PLMN from the list of the operator frequency information, and save the information to the registered cell list;

The search module is configured to search for available cell frequency points from the list of registered cells.

The terminal further includes an update module, configured to update the frequency point information stored in the operator frequency point information list.

The terminal further includes a full-band search module, configured to: when the search module does not search for available cell frequency points, perform full-band scanning on the frequency band supported by the terminal to search for available small-area frequency points.

Compared with the prior art, the present invention has the following advantages: since the frequency point information used by the current PLMN is saved in the registered cell list, the network is saved when the terminal is powered on or moved from the OOS area to the signal area. The time also reduces the power consumption of the terminal and increases the standby time of the terminal. DRAWINGS

1 is a schematic diagram of a terminal acquisition network provided by the prior art; 2 is a schematic diagram of a terminal capture network according to an embodiment of the present invention;

3 is a flowchart of automatically updating an operator frequency point information according to an embodiment of the present invention; FIG. 4 is a schematic structural diagram of a mobile communication terminal according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a list of carrier frequency information provided by an embodiment of the present invention. detailed description

The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings.

The protocol stack of the mobile terminal is generally divided into the NAS layer and the AS layer. The NAS is mainly responsible for protocol interaction with the core network. The AS is mainly responsible for interacting with the base station and the base station controller, and establishing an air interface connection for the NAS. After the terminal is powered on or returned from the no service area to the service area, the NAS first reads the current PLMN from the SIM/USIM card of the terminal, and then searches the carrier frequency information list for the frequency used by the current PLMN (operator). The frequency point information list is shown in Figure 5). If found, the NAS notifies the AS to add the frequency point information used by the current PLMN to the registered cell list, and then the NAS sends a network request to the AS. If not found, the NAS sends a request for a network directly to the AS.

In the present invention, when the NAS layer of the terminal protocol stack starts to search for a network, the frequency point information used by the current PLMN is added to the registered cell list (Strored cell list) of the terminal, so as to speed up the speed at which the terminal captures the network. The main improvement over the prior art is to add an interface for communication with the NAS at the AS layer, so that the AS can receive the frequency information used by the current PLMN from the NAS, and add the frequency information used by the current PLMN to the registered one. In the cell list.

When adding the frequency point information to the registered cell list, the AS layer first clears the frequency point information used by the previously added PLMN in the registered cell list, and then saves the frequency point information used by the current PLMN and notifies the NAS. Add frequency information successfully. After receiving the notification from the AS, the NAS sends a request for a network to the AS.

2 is a schematic diagram of a terminal capture network according to an embodiment of the present invention, as shown in FIG. The method of cell search is as follows:

Step 201: The NAS acquires the current PLMN. When the terminal is powered on or enters the service area from the no-service area, the NAS first checks whether there is an RPLMN in the SIM/USIM card of the terminal. If so, the RPLMN is obtained. If not, the HPLMN in the SIM/USIM card is read.

Step 202: The NAS searches the operator frequency information list for the frequency information used by the current PLMN. The frequency information of the carrier is stored in the carrier frequency information list. The NAS searches the carrier frequency information list for the frequency information used by the current PLMN. If found, the process proceeds to step 203. Otherwise, the process proceeds to step 206.

Step 203: The NAS requests the AS to add the frequency point information used by the current PLMN to the list of registered cells. The N AS sends an RRC Update Cell List (UPDATE CELL LIST) REQ message to the AS, requesting the AS to add the frequency point information used by the current PLMN to the registered cell list.

Step 204: The AS saves the frequency information used by the current PLMN in the registered cell list in response to the request of the NAS. After receiving the RRC UPDATE CELL LIST REQ message of the NAS, the AS first clears the frequency point information used by the previously added PLMN in the registered cell list, and then saves the frequency point information used by the current PLMN to the registered cell list. in.

Step 205: The AS sends a message to the NAS that the save is successful. After the AS saves the frequency information used by the current PLMN in the registered cell list, the AS returns an RRC UPDATE CELL LIST CNF message to the NAS to notify the NAS that the transmission is successful.

Step 206: The NAS sends a network request to the AS. The NAS sends an RRC PLMN Search REQ message to the AS, requesting the AS to start searching for available cell frequency points.

Step 207: The AS starts searching for available cell frequency points. After receiving the network request from the NAS, the AS searches for the available cell frequency points in the list of available cells that have been registered. The AS first searches the registered cell list for the frequency point that the terminal has registered last time. If the frequency point is the frequency of the available cell, step 208 is performed. Otherwise, the registered cell list is used to search for the current PLMN. Frequency Information, if an available cell frequency point is searched for in the frequency point information used by the current PLMN, step 208 is performed, otherwise, step 209 is skipped.

Step 208: The NAS is notified that the available cell is successfully searched. The AS sends an RRC PLMN Search CNF message to the NAS, informing the NAS that the available cell has been successfully searched. At this point, the entire cell search process is completed, and the following steps are no longer performed.

Step 209: The AS performs a full-band search on the frequency band supported by the terminal.

Step 210: The AS sends a full-band search result to the NAS. If the AS searches for an available cell when performing a full-band search on the frequency band supported by the terminal, the AS sends an RRC PLMN Search CNF message to the NAS, informing the NAS that the available cell is successfully searched. If no available cell is found at this time, the AS also sends an RRC PLMN Search CNF message to the NAS, notifying the NAS that no available cell is found, and notifying the currently existing cell to the NAS.

FIG. 3 is a flowchart of automatically updating carrier frequency information according to an embodiment of the present invention. As shown in FIG. 3, first, NAS searches for a frequency of an available cell, and if an available cell is searched, further acquires a broadcast message of the base station. The frequency information of the inter-frequency neighboring cell of the current cell is read in the broadcast message, thereby updating the carrier frequency point information list. If the NAS does not search for available cells, then a full band search is performed. In the process of searching in the full-band, if the cell is captured, the frequency of the captured cell is added to the carrier frequency information list, and the broadcast message of the base station is acquired, and the inter-frequency of the current cell is read from the broadcast message. The frequency point information of the neighboring cell, and then the operator frequency point information list is updated. If the full-band search does not capture the cell, then any cell search is performed.

After the terminal is powered on, the AS searches for the available cell in the registered cell list. If the terminal searches for the network, the terminal finds the network successfully, and then obtains the broadcast message sibll/sibl2/measurement control message from the base station (at CELL_DCH). The message is received in the state, and the frequency information of the inter-frequency neighboring cell of the currently available cell is read from the broadcast message. The frequency information of the inter-frequency neighboring cell is already present in the operator frequency information list. If not, the frequency information of the inter-frequency neighboring cell is added to the operator frequency information list. If the NAS does not search for available cells in the list of registered cells, the AS performs full-band scanning in the frequency band supported by the terminal. If the available cells are searched for, the corresponding frequency of the cell is definitely not in the carrier frequency list. Therefore, the available cell frequency points obtained by the full-band search are directly added to the operator frequency point information list. After the terminal finds the network successfully, it can obtain the broadcast message and the measurement control message of the base station, and read the frequency point information of the inter-frequency neighboring cell of the currently available cell from the broadcast message and the measurement control message, and determine the frequency of the inter-frequency neighboring cell. Whether the point information exists in the operator frequency point information list, if not, adds the frequency point information of the inter-frequency neighboring cell to the operator frequency point information list. If the full-band search does not find an available cell, then any cell search is performed.

In addition, when cell reselection or handover occurs in the terminal, it is also necessary to update the operator frequency point information list according to the broadcast message and the measurement control message. The update process is the same as the update process when the terminal is powered on.

4 is a schematic structural diagram of a mobile communication terminal according to an embodiment of the present invention. As shown in FIG. 4, a mobile communication terminal for accelerating cell search includes: an operator frequency point information list 1, a control module 2, a search module 3, and a Registered cell list 4. The business frequency information list 1 is used to store the frequency information used by the operator; the registered cell list 4 is used to store the frequency information of the registered cell and the frequency information used by the current PLMN; And searching for the frequency point information used by the current PLMN from the operator frequency point information list, and saving the information to the registered cell list; and searching module 3, for using the current PLMN used for saving from the registered cell list. Search for available cell frequencies in the point information. The mobile communication terminal further includes: an update module, configured to update frequency point information stored in the operator frequency point information list; and a full frequency band search module, when the available cell is not searched in the registered cell list, the full frequency band search module Perform a full-band search in the available frequency bands supported by the terminal to search for available cells.

In summary, the present invention saves the frequency information used by the current PLMN in the registered cell list, thereby saving the terminal from booting or moving from the non-service area to the service area. When the network is acquired, the power consumption of the terminal is also reduced, and the standby time of the terminal is increased.

Although the invention has been described in detail above, the invention is not limited thereto, and various modifications may be made by those skilled in the art in accordance with the principles of the invention. Therefore, modifications made in accordance with the principles of the present invention should be construed as falling within the scope of the present invention.

Claims

Claim

A method for accelerating cell search, characterized in that the method comprises the following steps:

B. If the frequency point information used by the current PLMN is found, the frequency information used by the current PLMN is saved to the list of cells registered by the terminal, and the frequency information used by the current PLMN is saved. Search for available cell frequency points in the list of registered cells; otherwise, search for available cell frequency points in the list of registered cells.

2. The method according to claim 1, wherein the step A comprises: the NAS layer of the terminal protocol stack reads the current PLMN stored in the terminal SIM/USIM card; and the NAS layer operates from the terminal stored in the terminal. Find the frequency information used by the current PLMN in the list of quotient frequency information.

The method according to claim 1, wherein in the step B, when the frequency point information is found, the process of performing the saving and searching includes:

The NAS layer sends a network request to the AS layer;

The method according to claim 3, wherein the searching for available cell frequency points from the list of registered cells storing the frequency point information used by the current PLMN comprises:

First search for the frequency points registered before the terminal, and then search for the frequency points used by the current PLMN.

The method according to claim 1, wherein in the step B, when the frequency point information is not found, the searching process includes:

The NAS layer sends a network request to the AS layer;

The method according to any one of claims 1 to 6, wherein the method further comprises: performing a full-band search process when the available cell frequency points are not searched in the list of registered cells, including:

Perform full-band scanning on the frequency bands supported by the terminal to search for available cell frequencies.

The method according to any one of claims 1 to 6, wherein the method further comprises the process of updating the operator frequency point information list, including:

Performing full-band search on the frequency band supported by the terminal. If the available cell frequency is searched, the searched available cell frequency points are added to the operator frequency information list stored in the terminal to update the carrier frequency. Point information list;

8. A mobile communication terminal for accelerating cell search, characterized in that

The terminal is provided with a list of carrier frequency information for storing frequency point information used by the operator, and a list of registered cells for storing frequency point information of the registered cell and frequency point information used by the current PLMN.

The terminal includes:

The terminal according to claim 8, wherein the terminal further comprises an update module, configured to update the frequency point information stored in the operator frequency point information list.

The terminal according to claim 8 or 9, wherein the terminal further comprises a full-band search module, configured to: when the search module does not search for an available cell frequency point, on a frequency band supported by the terminal Perform a full band scan to find available cell frequencies.