CN101980571A - Method for accelerating cell search and mobile communication terminal - Google Patents

Abstract

The invention discloses a method for speeding up cell search and a mobile communication terminal. When the terminal searches for a cell frequency point, it searches for the frequency point information currently used by the PLMN from the operator's frequency point information list of the terminal, and adds the frequency point information found Go to the terminal's registered cell list, and then search for available cell frequencies in the registered cell list. Since the frequency point information used by the current PLMN is saved in the list of registered cells, the terminal will quickly search for available cells when searching for a network, thereby greatly speeding up the speed of the terminal capturing the network and reducing the power consumption of the terminal. Power, improve the standby time of the terminal.

Description

A method and mobile communication terminal for speeding up cell search

technical field

The present invention relates to a digital communication method and a terminal, in particular to a method for speeding up cell search and a mobile communication terminal. Specifically, when the NAS layer of the terminal protocol stack starts to search for a network, the frequency point used by the current PLMN is The information is added to the terminal's registered cell list (Strored cell list) to speed up the terminal's capture of the network.

Background technique

At present, the process of the terminal being powered on and capturing the network from the OOS (Out Of Service) area to the signal area is shown in Figure 1:

After obtaining the current PLMN, the NAS layer of the terminal protocol stack sends a network search request to the AS layer of the terminal protocol stack. The NAS checks whether there is an RPLMN (the PLMN registered last time, stored in the SIM/USIM card) in the terminal, if not, selects the HPLMN (belonging to the PLMN, stored in the SIM/USIM card), and then the NAS sends the RRC PLMN to the AS Search REQ message, requesting the AS to search for available cells of the current PLMN.

After receiving the network search request from the NAS layer, the AS layer scans the entire frequency band on the frequency band supported by the terminal to search for available cells. When the AS searches for a frequency point, it first searches for a frequency point registered by the terminal before. If an available cell is found, the AS sends an RRC PLMN serarch CNF message to the NAS to notify the NAS that a suitable cell has been found. If no cell information is found or there is no previously registered cell information in the terminal's memory, the AS layer will search for the entire frequency band according to the frequency band supported by the terminal. This process will take a long time. If an available cell is found, the AS will notify The NAS has found a suitable cell. If not, the AS will send the currently existing network to the NAS, and the NAS will select an available PLMN according to the priority of the PLMN. The priority order of PLMN is as follows:

1. HPLMN.

2. "USER Controlled PLMN Selector with Access Technology" stored in the SIM card.

3. "Operator Controlled PLMN Selector with Access Technology" stored in the SIM card.

4. Randomly select other networks with high signal quality.

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

According to the current method of capturing cells, if the user turns on for the first time or the user moves to another place or the user moves from an OOS area to an area with a signal, because the terminal does not store the information of the registered network before the shutdown, or because the stored network information and the current network information Inconsistent, the time for the terminal to capture the network will be very long. Moreover, generally an operator will only use a few frequency points in a frequency band, and will not use hundreds of frequency points in the entire frequency band. Therefore, the terminal will spend most of its time searching for frequencies that the operator does not use at all. point.

Contents of the invention

The purpose of the present invention is to provide a method for speeding up cell search and a mobile communication terminal, which can better solve the problem that the terminal does not store the information registered on the network before shutdown or the stored network information is inconsistent with the current network information. long question.

According to one aspect of the present invention, a method for speeding up cell search is provided, characterized in that the method comprises the following steps:

(A) When the terminal searches for a cell frequency point, it searches the frequency point information used by the current PLMN from the operator frequency point information list stored in the terminal;

(B) If the frequency point information used by the current PLMN is found in step (A), then the found frequency point information used by the current PLMN is stored in the list of cells registered by the terminal, and in the Search available cell frequencies in the registered cell list.

(C) If the frequency point information used by the current PLMN is not found in step (A), search for available cell frequency points in the registered cell list.

The step (A) of the method is specifically: 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 current PLMN used by the current PLMN from the operator frequency information list stored in the terminal. Frequency information.

The step (B) of the method is specifically: the NAS layer sends to the AS layer of the terminal protocol stack an addition request to add the frequency point information used by the current PLMN in the registered cell list; the AS layer responds to the addition request of the NAS layer, clears The frequency point information used by the PLMN previously added in the registered cell list saves the frequency point information used by the current PLMN sent by the NAS in the registered cell list; the NAS layer sends a network search request to the AS layer; The AS layer responds to the network search request of the NAS layer, searches for available cell frequency points from the registered cell list, and sends the search results to the NAS layer.

In this method, searching for available cell frequency points from the registered cell list storing the frequency point information used by the current PLMN is specifically: firstly searching for the frequency points registered by the terminal before, and then searching for the frequency points used by the current PLMN.

The step (C) of the method is specifically: the NAS layer sends a network search request to the AS layer; the AS layer responds to the network search request of the NAS layer, searches for available cell frequency points from the registered cell list, and sends the search result to the NAS layer.

The method also includes performing a full frequency band search step when no available cell frequency point is found in the registered cell list, specifically: performing full frequency band scanning on a frequency band supported by the terminal to search for available cell frequency points.

The method also includes the step of updating the operator's frequency point information list, which can be specifically implemented in the following manner: perform a full frequency band search on the frequency band supported by the terminal, and if an available cell frequency point is found, add the searched available cell frequency point to to the operator’s frequency point information list stored in the terminal to update the operator’s frequency point information list; the terminal reads the frequency point information of the inter-frequency adjacent cell of the current cell from the message sent by the base station, and adds it to Stored in the operator's frequency point information list in the terminal, so as to update the operator's frequency point information list.

According to another aspect of the present invention, a mobile communication terminal for speeding up cell search is provided, characterized in that it includes:

The business frequency point information list is used to save the frequency point information used by the operator;

The registered cell list is used to save the frequency point information of the registered cell and the frequency point information used by the current PLMN;

A control module, configured to search the frequency point information used by the current PLMN from the operator's frequency point information list, and save it in the registered cell list;

The search module is used to search for available cell frequency points from the registered cell list.

The mobile communication terminal also includes: an updating module, used for updating the frequency point information stored in the operator's frequency point information list.

The mobile communication terminal also includes: a full frequency band search module, when the search module does not find an available cell frequency point, it scans the entire frequency band on the frequency band supported by the terminal to search for an available cell frequency point.

Compared with the prior art, the beneficial effect of the present invention is that since the frequency point information used by the current PLMN is saved in the registered cell list, it saves the need to capture network information when the terminal is turned on or moves from an OOS area to a signal area. It also reduces the power consumption of the terminal and improves the standby time of the terminal.

Description of drawings

FIG. 1 is a schematic diagram of a terminal capture network provided by the prior art;

FIG. 2 is a schematic diagram of a terminal capture network provided by an embodiment of the present invention;

Fig. 3 is a flow chart of automatically updating operator frequency point information provided by an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a mobile communication terminal provided by an embodiment of the present invention;

FIG. 5 is a schematic diagram of a list of operator frequency point information provided by an embodiment of the present invention;

Detailed ways

The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described below are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

The protocol stack of the mobile terminal is generally divided into the NAS layer and the AS layer. The NAS is mainly responsible for the protocol interaction with the core network, and the AS is mainly responsible for the interaction with the base station and the base station controller, and establishes an air interface connection for the NAS. After the terminal is powered on or returns to a service area from an unserved area, the NAS first reads the current PLMN from the terminal's SIM/USIM card, and then searches the frequency point used by the current PLMN from the operator's frequency point information list (operator The frequency point information list is shown in Figure 5). If it is found, the NAS will notify the AS to add the frequency point information used by the current PLMN to the registered cell list, and then the NAS will send a network search request to the AS. If not found, the NAS directly sends a network search request to the AS.

The main improvement of the present invention is that an interface for communicating with NAS is added at the AS layer, so that AS can receive the frequency point information used by the current PLMN from the NAS, and add the frequency point information used by the current PLMN to the registered cell list middle. When the AS layer adds frequency point information to the registered cell list, it 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 The frequency point information is added successfully. After receiving the notification from the AS, the NAS sends a network search request to the AS.

FIG. 2 is a schematic diagram of a terminal capture network provided by an embodiment of the present invention. As shown in FIG. 2, the specific cell search method is as follows:

Step 201: the NAS obtains the current PLMN. When the terminal is powered on or enters an area with service from an unserved area, the NAS first checks whether there is an RPLMN in the SIM/USIM card of the terminal, if yes, obtains the RPLMN, and if not, reads the HPLMN in the SIM/USIM card.

Step 202: The NAS searches the frequency point information currently used by the PLMN in the operator's frequency point information list. The frequency information used by the operator is stored in the operator frequency information list. The NAS searches the frequency point information used by the current PLMN in the operator's frequency point information list, and if found, executes step 203; otherwise, skips to step 206.

Step 203: The NAS requests the AS to add the frequency information used by the current PLMN to the list of registered cells. The NAS sends an RRC UPDATE CELLLIST REQ message to the AS, requesting the AS to add the frequency information used by the current PLMN to the list of registered cells.

Step 204: The AS responds to the request of the NAS, and saves the frequency point information currently used by the PLMN in the registered cell list. After the AS receives the RRC UPDATE CELL LIST REQ message from the NAS, it 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 middle.

Step 205: the AS sends a message of successful storage to the NAS. After the AS saves the frequency point information used by the current PLMN in the registered cell list, it returns the RRC UPDATE CELLIST CNF message to the NAS to notify the NAS of the successful saving.

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

Step 207: the AS starts to search for available cell frequency points. After receiving the network search request from the NAS, the AS searches for available cell frequencies in the list of registered available cells. The AS first searches the registered cell list for the frequency point that the terminal registered last time. If the frequency point is the frequency point of an available cell, execute step 208; otherwise, search for the frequency point used by the current PLMN in the registered cell list. For frequency point information, if an available cell frequency point is found in the frequency point information used by the current PLMN, execute step 208; otherwise, skip to step 209.

Step 208: Notifying the NAS that an available cell has been found successfully. The AS sends an RRC PLMNSearch CNF message to the NAS to notify the NAS that an available cell has been successfully searched. At this point, the entire cell search process is completed, and the following steps are not performed any more.

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

Step 210: the AS sends the full frequency 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 to notify the NAS that it has successfully searched for an available cell. If no available cell has been found at this time, the AS will also send an RRC PLMN Search CNF message to the NAS, informing the NAS that no available cell has been found, and notify the NAS of the currently existing cells.

Figure 3 is a flow chart for automatically updating operator frequency point information provided by an embodiment of the present invention. As shown in Figure 3, the NAS first searches for the frequency point of an available cell, and if an available cell is found, it further obtains a broadcast message from the base station, from Read the frequency point information of the adjacent cells with different frequencies in the current cell in the broadcast message, so as to update the operator's frequency point information list. If the NAS does not find an available cell, it will perform a full frequency band search. In the process of full-band search, if a cell is captured, the frequency point of the captured cell will be added to the operator's frequency point information list, and at the same time, the broadcast message of the base station will be obtained, and the different frequency of the current cell will be read from the broadcast message The frequency point information of adjacent cells, and then update the operator's frequency point information list. If no cell is captured by the full frequency band search, any cell search is performed.

After the terminal is powered on, the AS first searches for available cells in the registered cell list (stored cell list). If the search is found, the terminal successfully finds the network, and then obtains the broadcast message sib11/sib12/measurement control message from the base station (in the CELL_DCH The message will be received in the state), and read the frequency point information of the inter-frequency adjacent cells of the currently available cell from the broadcast message. Check whether the frequency point information of the inter-frequency adjacent cell already exists in the operator's frequency point information list, and if not, add the frequency point information of the inter-frequency adjacent cell to the operator's frequency point information list.

If the NAS cannot search for an available cell in the registered cell list, the AS will scan the entire frequency band in the frequency band supported by the terminal. If an available cell is found at this time, the corresponding frequency point of the cell must not be in the operator's frequency point information list. Therefore, directly add the frequency points of the available cells obtained from the full frequency band search to the operator's frequency point information list. After the terminal successfully finds the network, it can obtain the broadcast message and measurement control message of the base station, and read the frequency point information of the inter-frequency adjacent cell of the currently available cell from the broadcast message and measurement control message, and judge the frequency of the inter-frequency adjacent cell. Whether the point information exists in the operator's frequency point information list, if not, then add the frequency point information of the inter-frequency adjacent cell to the operator's frequency point information list. If no available cell is found in the full frequency band search, search for any cell.

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

FIG. 4 is a schematic structural diagram of a mobile communication terminal provided by an embodiment of the present invention. As shown in FIG. Registered cell list4. The business frequency point information list 1 is used to save the frequency point information used by the operator; the registered cell list 4 is used to save the frequency point information of the registered cell and the frequency point information used by the current PLMN; the control module 2, Used to search the frequency point information used by the current PLMN from the operator's frequency point information list, and save it in the registered cell list; the search module 3 is used to save the frequency used by the current PLMN from the registered cell list. Search available cell frequency points in point information. The mobile communication terminal also includes: an update module, used to update the frequency point information stored in the operator's frequency point information list; a full frequency band search module, when no available cell is found in the registered cell list, the full frequency band search module Perform a full frequency band search in the available frequency bands supported by the terminal to search for available cells.

To sum up, the present invention saves the frequency point information used by the current PLMN in the registered cell list, saves the time for capturing the network when the terminal is turned on or moves from an unserved area to a service area, and also reduces The power consumption of the terminal increases the standby time of the terminal.

Although the present invention has been described in detail above, the present invention is not limited thereto, and various modifications can be made by those skilled in the art based on the principle of the present invention. Therefore, any modifications made according to the principles of the present invention should be understood as falling within the protection scope of the present invention.

Claims (10)

1. method of accelerating Cell searching is characterized in that this method may further comprise the steps:

(A) during the terminal searching subdistrict frequency point, search the employed frequency point information of current public land mobile network PLMN in the operator's frequency point information tabulation from be stored in terminal;

(B) if in step (A), find the employed frequency point information of current PLMN, the employed frequency point information of current PLMN that then will find is saved in the registered cell list of terminal, and in the described registered cell list of preserving the frequency point information that current PLMN uses search available cell frequency.

(C), then in registered cell list, search for the available cell frequency if in step (A), do not find the employed frequency point information of current PLMN.

2. quickening small region search method according to claim 1 is characterized in that described step (A) comprising:

The NAS layer of terminal protocol stack reads the current PLMN that is stored in the terminal SIM/USIM card;

Search the frequency point information that current PLMN uses operator's frequency point information tabulation of NAS layer in being stored in terminal.

3. quickening small region search method according to claim 2 is characterized in that described step (B) comprising:

The AS layer of NAS course terminal protocol stack sends the interpolation request of adding the employed frequency point information of current PLMN in registered cell list;

The employed frequency point information of PLMN of adding before in the registered cell list is removed in the interpolation request of AS layer response NAS layer, and the employed frequency point information of current PLMN that NAS is sent is saved in the described registered cell list;

NAS course AS layer sends the net request of looking for;

The net of looking for of AS layer response NAS layer is asked, and searches for the available cell frequency from the registered cell list of preserving the employed frequency point information of current PLMN, and Search Results is sent to the NAS layer.

4. quickening small region search method according to claim 3 is characterized in that the described available cell frequency of searching for comprises from the registered cell list of preserving the employed frequency point information of current PLMN:

At first the frequency of registering before the search terminal is searched for the employed frequency of current PLMN again.

5. quickening small region search method according to claim 2 is characterized in that described step (C) comprising:

NAS course AS layer sends the net request of looking for;

The net of looking for of AS layer response NAS layer is asked, and searches for the available cell frequency from registered cell list, and Search Results is sent to the NAS layer.

6. quickening small region search method according to claim 1 is characterized in that also being included in and carries out the full frequency band search step when not searching the available cell frequency in the described registered cell list, comprising:

On the frequency range of terminal support, carry out full frequency band scanning, with search available cell frequency.

7. according to each described quickening small region search method of claim 1 to 6, it is characterized in that described method also comprises the step of upgrading operator's frequency point information tabulation, comprising:

On the frequency range of terminal support, carry out the full frequency band search,, then the available cell frequency that searches is added in the operator's frequency point information tabulation that is stored in the terminal, to upgrade the frequency point information tabulation of described operator if search the available cell frequency;

Terminal reads the frequency point information of the alien frequencies neighbor cell of current area from the message that the base station sends, and adds in the operator's frequency point information tabulation that is stored in the terminal, to upgrade the frequency point information tabulation of described operator.

8. mobile communication terminal of accelerating Cell searching is characterized in that comprising:

Operator's frequency point information tabulation is used to preserve the employed frequency point information of operator;

Registered cell list is used to preserve the frequency point information and the employed frequency point information of current PLMN of registered sub-district;

Control module is used for searching the employed frequency point information of current PLMN from the frequency point information tabulation of described operator, and is saved in the registered cell list;

Search module is used for from registered cell list search available cell frequency.

9. the mobile communication terminal of quickening Cell searching according to claim 8 is characterized in that the mobile communication terminal of described Cell searching also comprises:

Update module is used for upgrading the frequency point information that is kept at operator's frequency point information tabulation.

10. the mobile communication terminal of quickening Cell searching according to claim 8 is characterized in that also comprising:

The full frequency band search module, when search module did not search the available cell frequency, full frequency band scanning on the frequency range that terminal is supported was to search the available cell frequency.

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