TWI481270B - Method of controlling home cell selection for a wireless communication system and related device - Google Patents

Description

Method for controlling special cell selection by wireless communication system and related device

The present invention relates to a method for a wireless communication system and a communication device thereof, and more particularly to a method for a wireless communication system and a communication device thereof, to save power consumption of a cell selection operation of a roaming user terminal.

System Architecture Evolution (SAE) system, standardized by the 3rd Generation Mobile Communications Alliance (3GPP), is a new core network architecture of the Universal Mobile Telecommunications System (UMTS), which is the Internet. The mass market of the Internet Protocol (IP) provides cost-effective deployment and operation. Network evolution mainly includes meeting the wireless interface requirements of a long term evolution (LTE) system, simplifying the network structure, and all-IP networks, that is, all services use packet switching for transmission, wireless channel switching, and support for different services. Access to inter-network mobility and service continuity, such as 2G/3G, Long Term Evolution, and non-3GPP access systems.

The system architecture evolution system includes a Mobility Management Entity (MME), a Serving Gateway (S-GW), and a PDN Gateway (P-GW). The mobile management system is a control plane entity that manages network service attach, client authentication, and coordination of the establishment of associated wireless bearers for the evolved wireless access network.

The function of the system architecture evolution system includes the non-access layer function performed by the client in the idle mode, and the user terminal and the evolved packet core network are performed by an evolved universal mobile communication system (Evolved UMTS, E-UTRAN). The non-access layer signaling process and the third layer signaling flow transmitted between the UE and the evolved packet core network through the non-3GPP access network. The evolved universal mobile communication system includes a plurality of evolved base stations.

In the non-access layer, the Home Cell is deployed to use a single base station for a home range, a building range, or a small cell group (eg, in a campus range). Eligibility for access to a particular cell is limited to the intended user. A Closed Subscriber Group (CSG) cell can be considered a unique cell that is part of the Public Land Mobile Network (PLMN). In addition, when the cell identification of a closed user group cell is stored in a white list of a user terminal, the user terminal can access the closed user group cell. In other words, the whitelist is used to provide cell identification for a plurality of accessible closed user group cells, allowing the client to reside in a closed user group of cells on the whitelist. In general, the whitelist is determined by the public land mobile network.

A roaming client refers to a client moving from a mass transit mobile network to other mass transit mobile networks. The public place mobile network that the user leaves is called a local network, and the public place mobile network that the user station is temporarily called is a visiting network. When a client with a whitelist roams to a visited network, the visited network cannot know whether the whitelist is stored by the client, and therefore the visited network cannot process the whitelist. When the client is stationed in one of the visiting networks (Macro Cell), the client will try to search for closed user group cells in the whitelist. However, closed user group cells visiting the network are usually not on the whitelist of the client. In this case, the client continuously performs closed user group cell search, but does not search for any accessible closed user group cells, so that unnecessary cell search procedures may cause unnecessary power consumption at the user end.

The present invention provides a method and associated communication device for conserving power consumption of a particular cell selection operation of a roaming user terminal of a wireless communication system.

The invention discloses a method for saving power consumption of a special cell selection operation, which is used for a user end of a wireless communication system, the user end comprising a white list for providing a plurality of accessible special cells, the method The method includes: when the client roams to a visiting network, the whitelist is cleared.

The invention further discloses a communication device for a wireless communication system, which is used for saving power consumption of a special cell selection operation of a user terminal, and the user terminal comprises a white list for providing a plurality of accessible specialities. Is a cell. The communication device includes a processor, a communication interface unit, a control unit, and a computer readable recording medium. The processor is configured to process a stored data; the communication interface unit is configured to exchange wireless signals with a remote communication device of the wireless communication system; the control unit is coupled to the processor and the communication interface unit, The communication interface unit and the communication device are controlled according to the processing result of the processor; the computer can read the recording medium and is coupled to the processor for storing the stored data. The stored data includes a program for clearing the whitelist when the client roams to a visited network.

The invention further discloses a method for saving power consumption of a special cell selection operation, which is used for a user end of a wireless communication system, the user end comprising a white list for providing a plurality of accessible special cells and corresponding In the network of the plurality of accessible special cells, the method includes: when the user roams to a visiting network and resides in a macro cell of the visiting network, searching for a special cell in the whitelist; detecting the presence of the visiting network in the whitelist; and stopping searching for the whitelist when the visiting network is not detected from the whitelist Multiple specific cells.

The invention further discloses a communication device for a wireless communication system, which is used for saving power consumption of a special cell selection operation of a user terminal, and the user terminal comprises a white list for providing a plurality of accessible specialities. Is a cell. The communication device includes a processor, a communication interface unit, a control unit, and a computer readable recording medium. The processor is configured to process a stored data; the communication interface unit is configured to exchange wireless signals with a remote communication device of the wireless communication system; the control unit is coupled to the processor and the communication interface unit, The communication interface unit and the communication device are controlled according to the processing result of the processor; the computer can read the recording medium and is coupled to the processor for storing the stored data. The stored data includes a white list for providing a plurality of accessible special cells and a network corresponding to the plurality of accessible special cells; a first program for using the client Roaming to a visiting network and detecting the presence of the visiting network in the whitelist when the macro cell is located in the visiting network; and a second program for using the parameter When the visited network is not detected from the white list, the search for the plurality of unique cells in the white list is stopped.

Please refer to FIG. 1 , which is a schematic diagram of a wireless communication system 10 . The architecture of the wireless communication system 10 is based on a system architecture evolution (SAE), a Universal Mobile Telecommunications System (UMTS), or a hybrid system of a system architecture evolution system and a universal mobile communication system. The wireless communication system 10 includes a client 100 and a Public Land Mobile Network (PLMN) 110 and 120, wherein the PLMNs 110 and 120 include Home Location Registers (HLRs) 112 and 122, and visits. Location Registers (VLRs) 114 and 124, and Base Station Systems (BSSs) 116 and 126. The client 100 can support a system architecture evolution system and a universal mobile communication system, and can be applied to the wireless communication system 10. The local location register 112 records that the client 100 is a dedicated client. When the client 100 resides in a macro cell of the PLMN 110, the PLMN 110 can process a whitelist of the client 100, which provides a plurality of accessible Closed Subscriber Group (CSG) cells for which The field has a Home Cell that is well known to those of ordinary skill. The client 100 searches for appropriate CSG cells for use in the CSG service based on the whitelist.

When the UE 100 roams from the PLMN 110 to the PLMN 120, the PLMN 110 is treated as a local network and the PLMN 120 is considered a visited network. The visitor location register 124 determines that the client 100 is a visitor, and therefore provides a wireless interface through the base station system 126 for user action management, authentication, and authorization and billing procedures. During the roaming process, the PLMN 120 cannot know whether the client 100 has stored a white list.

Please refer to FIG. 2, which is a schematic diagram of a wireless communication device 20 according to an embodiment of the present invention. The wireless communication device 20 can be the client 100 in FIG. 1 and includes a processor 200, a computer readable recording medium 210, a communication interface unit 220, and a control unit 230. The computer readable recording medium 210 can be any data storage device for storing a stored data 212, which includes a program and a white list, which are read and processed by the processor 200. The computer readable recording medium 210 can be a read-only memory (ROM), a random-access memory (RAM), a CD-ROM (a CD-ROM), or a tape ( Magnetic tapes), floppy disks, optical data storage devices, and carrier signals (such as data transmission over the Internet). The control unit 230 is configured to control the status and related operations of the communication interface unit 220 and the communication device 20 according to the processing result of the processor 200. The communication interface unit 220 is preferably a wireless receiver for wireless communication with the base station, wherein the base station can be one of the base stations of the base station system 126 of FIG.

The whitelist of communication devices 20 described above can provide a plurality of CSG cells and associated networks, the CSG cells of which can be accessed by the communication device 20 and provided by a local network. Through the whitelist, when the communication device 20 resides in a macro cell of the local network, the communication device 20 can search for CSG cells in the whitelist to use the CSG service. When the communication device 20 roams from the local network to a visiting network, the communication device 20 stops searching for CSG cells in accordance with the inventive concept.

One embodiment of the present invention provides a whitelist removal procedure to prevent the communication device 20 from searching for CSG cells.

Please refer to FIG. 3 , which is a schematic diagram of a white list clearing process 30 according to an embodiment of the present invention. The whitelist clearing process 30 is used for one of the wireless communication systems to save the power consumption of a CSG cell selection operation of a client (such as the client 100), and can be compiled to be stored in a computer readable record. The program in the storage 210 of the media 210. The whitelist removal process 30 includes the following steps:

Step 300: Start.

Step 302: When the client roams to a visited network, the whitelist is cleared.

Step 304: End.

According to the whitelist clearing process 30, when the user roams to the visiting network, the visiting network can clear the whitelist. Preferably, the visiting network clears the whitelist using a whitelist update process. The whitelist update process may be at least one of an additional process initiated by the client, a tracking area update process, a location area update process, and a routing area update process.

When the user roams to the visited network, the whitelist removal process 30 does not search for CSG cells, and when the user station is in a macro cell, the CSG cells listed in the white list are cleared. Therefore, CSG cell selection will not be performed. Therefore, the user can avoid power consumption when searching for CSG cells.

The embodiment of the whitelist removal process 30 can be applied to the client 100 of FIG. When the UE 100 roams from the PLMN 110 to the PLMN 120, the UE initiates an additional procedure by transmitting an ATTACH REQUEST message to the PLMN 120. The PLMN 120 then places a blank white list in an ATTACH ACCEPT message and transmits the additional acceptance message to reply to the additional request message. After the user receives and reads the additional acceptance message, all CSG cells in the whitelist are removed. Therefore, after roaming to the PLMN 120, the UE 100 does not continue to search for CSG cells.

Another embodiment of the present invention provides a visited network detection process to prevent the communication device 20 from searching for CSG cells.

Please refer to FIG. 4, which is a schematic diagram of a visited network detection process 40 according to an embodiment of the present invention. The visit network detection process 40 is used in a client to save power consumption of the CSG cell selection operation of the client, and can be compiled into a program stored in the storage data 212 of the computer readable recording medium 210. The visit network detection process 40 includes the following steps:

Step 400: Start.

Step 402: When the user station resides in a macro cell of a visiting network, detecting the presence of the visiting network in the white list.

Step 404: When the visited network is not detected from the white list, stop searching for CSG cells in the white list.

Step 406: End.

According to the visiting network detection process 40, when roaming to the visiting network and stationing in the macro cell, the presence of the visiting network in the whitelist is first detected to determine whether the visiting network is white. The list of accessible networks is available. When the client does not detect the visited network from the whitelist, it stops searching for CSG cells in the whitelist.

The embodiment of the visited network detection process 40 can be applied to the client 100 of FIG. In order to provide CSG services, PLMN 110 provides a whitelist of client 100 that contains a list of a plurality of accessible CSG cells and their associated networks. For example, the whitelist contains the identification of accessible CSG cells and network identification corresponding to these CSG cells. When the UE 100 roams from the PLMN 110 to the PLMN 120, the UE 100 determines whether the PLMN 120 is in the white list. When the client 100 is unable to find the PLMN 120 in the whitelist, then all CSG cells in the whitelist are not in the range of the PLMN 120. In this case, the client 100 stops the CSG cell search to save power. The UE 100 can determine whether to stop the CSG cell search according to the system information broadcast by the PLMN 120, and the system data includes the network identification of the PLMN 120.

According to the visited network detection process 40, steps 404 and 402 can be simplified as follows: the user detects the presence of the visited network; when the visited network exists (enters), the user stops searching for the CSG cells.

The following is another embodiment of the visit network detection process 40 applied to the client 100. Similarly, PLMN 110 provides a whitelist of client 100 to provide CSG services. The whitelist contains the identification of accessible CSG cells and the identification of their associated networks. When the UE 100 roams from the PLMN 110 to the PLMN 120, the UE 100 detects whether the PLMN 120 is a visited network. When the UE 100 determines that the PLMN 120 is a visiting network, the CSG cell search is stopped to save power. Similarly, the client 100 can decide whether to stop the CSG cell search based on the network identification in the system data broadcast by the PLMN 120.

In summary, the embodiment of the present invention solves the problem of CSG cell search for wasted power by roaming the whitelist or detecting the existence of the visited network.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

10. . . Wireless communication system

100. . . user terminal

110, 120. . . Public place mobile network

112, 122. . . Local location register

114, 124. . . Visit location register

116, 126. . . Base station system

20. . . Communication device

200. . . processor

210. . . Computer readable recording medium

220. . . Communication interface unit

230. . . control unit

212. . . Storage data

30, 40. . . Process

300, 302, 304, 400, 402, 404, 406. . . step

Figure 1 is a schematic diagram of a wireless communication system.

FIG. 2 is a schematic diagram of a communication device according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of a white list clearing process according to an embodiment of the present invention.

FIG. 4 is a schematic diagram of a visit network detection process according to an embodiment of the present invention.

30. . . Process

300, 302, 304. . . step

Claims (11)

A method for saving power consumption of a closed user group cell selection operation, which is used for a user end of a wireless communication system, the method comprising: stopping the search for a closed user group cell when the user side roams to a visiting network, The client includes a whitelist that provides identification of a plurality of accessible closed subscriber group cells and at least one network of public land mobile networks corresponding to the plurality of accessible closed subscriber group cells The step of identifying, and stopping searching for the closed user group cells includes: detecting the presence of the visited network; and stopping searching for the plurality of accessible closed user group cells when the visiting network exists. The method of claim 1, wherein the stopping the searching for the closed user group cell comprises clearing the whitelist of the user terminal. The method of claim 2, wherein the clearing of the whitelist includes clearing the whitelist through a whitelist update process when the client roams to the visited network. The method of claim 3, wherein the whitelist update process includes at least one of an additional process, a tracking area update process, a location area update process, and a routing area update process. The method of claim 1, wherein the stopping the searching for the closed user group cell comprises: detecting the presence of the visiting network in the whitelist when resident in the macro cell of the visiting network; And when the visiting network is not detected from the whitelist, stop searching for the plurality of accessible closed user group cells provided by the whitelist. A communication device for a wireless communication system for saving power consumption of a closed user group cell selection operation, the communication device comprising: a processor for processing a stored data; and a communication interface unit for a remote communication device of the wireless communication system exchanges wireless signals; and a computer readable recording medium coupled to the processor for storing the stored data; wherein the stored data includes: a white list for Providing a plurality of accessible closed user group cells for identification and at least one network identification of a mass land mobile network corresponding to the plurality of accessible closed user group cells; a first program for detecting a visiting network; and a second program for stopping searching for the closed user group cells when the visiting network exists. The communication device of claim 6, wherein the cessation of searching for the plurality of accessible closed user group cells comprises clearing the whitelist. The communication device of claim 7, wherein the whitelist is cleared by a whitelist update process. The communication device of claim 8, wherein the whitelist update process includes at least one of an additional process, a tracking area update process, a location area update process, and a routing area update process. A communication device for a wireless communication system for saving power consumption of a closed user group cell selection operation, the communication device comprising: a processor for processing a stored data; a communication interface unit for exchanging wireless signals with a remote communication device of the wireless communication system; and a computer readable recording medium coupled to the processor for storing the stored data; wherein the stored data includes There is: a white list for providing identification of a plurality of accessible closed user group cells and at least one network identification of a mass land mobile network corresponding to the plurality of accessible closed user group cells; a first program for detecting the presence of the visiting network in the whitelist; and a second program for stopping searching for the white when the visiting network is not detected from the whitelist The plurality of accessible closed user group cells of the list. A method for saving power consumption of a closed user group cell selection operation for use in a network of a wireless communication system, the method comprising: providing an identification of a plurality of accessible closed user group cells and at least one corresponding to A whitelist of network identifications of the plurality of accessible closed subscriber group cells of the mass transit mobile network to a subscriber end of the wireless communication system.