Network search method and terminal device

• US 10,701,612 B2
• Filed: 05/06/2016
• Issued: 06/30/2020
• Est. Priority Date: 05/06/2016
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Yu, Hsiu, Huang, Chengsheng, Shu, Haw-Wei, Chang, Yifang
• Primary Examiner(s): Nawaz, Asad M
• Assistant Examiner(s): Cairns, Thomas R
• Application Number:
  US16/099,407
• Publication Number:
  US 20190159101A1
• Time in Patent Office: 1,516 Days
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 36/322 by location data
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 8/183 Processing at user equipment or user record carrier
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems

Abstract

Embodiments of this application disclose a network search method and a terminal device. The network search method is applied to a terminal device, and a subscriber identity module SIM card is installed in the terminal device. The method part in the embodiments of this application includes: when the terminal device camps on a visited public land mobile network VPLMN, determining an MCC home area corresponding to the SIM card; determining whether the terminal device has entered the MCC home area or is to enter the MCC home area; and triggering a network search if the terminal device has entered the MCC home area or is to enter the MCC home area. The embodiments of this application also disclose the terminal device, so as to increase a speed of going back, by the terminal device, from the VPLMN network to camp on an HPLMN network.

Claims

1. A network search method, wherein the method is applied to a terminal device, a subscriber identity module (SIM) card is installed in the terminal device, and the method comprises:

when the terminal device camps on a visited public land mobile network (VPLMN), determining a mobile country code (MCC) home area corresponding to the SIM card;

determining whether the terminal device has entered the MCC home area or is to enter the MCC home area, wherein the determining whether the terminal device has entered the MCC home area comprises;

determining a quantity of first cells, wherein the first cells are all cells that can be found currently by the terminal device;

determining a proportion of second cells in the first cells, wherein each second cell is a cell, whose MCC is the same as an MCC corresponding to the SIM card, in the first cells; and

if the proportion of the second cells in the first cells is greater than a preset proportion, determining that the terminal device has entered the MCC home area, wherein the preset proportion is not equal to zero; and

triggering a network search if the terminal device has entered the MCC home area or is to enter the MCC home area.

2. The network search method according to claim 1, wherein the triggering a network search comprises:

determining first timing duration according to the proportion of the second cells in the first cells;

setting the first timing duration as timing duration of a target timer, and starting timing when determining that the terminal device enters the MCC home area; and

triggering the network search when a time of the target timer exceeds the first timing duration.

3. The network search method according to claim 2, wherein the determining first timing duration according to the proportion of the second cells in the first cells comprises:

determining the first timing duration T1 according to the following formula;

4. The network search method according to claim 2, wherein the method further comprises:

if the proportion of the second cells in the first cells is less than or equal to the preset proportion, determining second timing duration according to the proportion of the second cells in the first cells;

setting the second timing duration as duration of the target timer; and

triggering the network search when a time of the target timer exceeds the second timing duration.

5. The network search method according to claim 4, wherein the determining second timing duration according to the proportion of the second cells in the first cells comprises:

determining the second timing duration T2 according to the following formula;

6. The network search method according to claim 1, before the determining whether the terminal device is to enter the MCC home area, further comprising:

recording an identity of a third cell and an identity of a neighboring cell of the third cell, wherein the third cell is the first VPLMN cell on which the terminal device camps when entering a VPLMN area from the MCC home area; and

if determining, according to the identities, that a currently camped-on cell is the third cell or the neighboring cell of the third cell, determining that the terminal device is to enter the MCC home area.

7. The network search method according to claim 1, wherein the triggering a network search comprises:

performing the network search in a manner of triggering a higher priority PLMN search.

8. A terminal device, comprising:

a transmitter, an antenna, a bus, at least one processor, and a memory, wherein;

the transmitter, the at least one processor, and the memory are connected by using the bus;

the antenna is connected to the transmitter; and

the memory is configured to store an instruction, and the at least one processor is configured to execute the instruction stored in the memory, so that the terminal device executes the processing method comprising;

when the terminal device camps on a visited public land mobile network (VPLMN), determining a mobile country code (MCC) home area corresponding to a subscriber identity module (SIM) card installed in the terminal device;

determining whether the terminal device has entered the MCC home area or is to enter the MCC home area, wherein the determining whether the terminal device has entered the MCC home area comprises;

determining a quantity of first cells, wherein the first cells are all cells that can be found currently by the terminal device;

determining a proportion of second cells in the first cells, wherein each second cell is a cell, whose MCC is the same as an MCC corresponding to the SIM card, in the first cells; and

if the proportion of the second cells in the first cells is greater than a preset proportion, determining that the terminal device has entered the MCC home area, wherein the preset proportion is not equal to zero; and

triggering a network search if the terminal device has entered the MCC home area or is to enter the MCC home area.