Method and Terminal Device for Cell Reselection

Abstract

A method and a terminal device for cell reselection are provided. The method is applied to a terminal device. A connection between the terminal device and a network device is in a disconnected state, and the network device retains context information of the terminal device, the context information being used to establish a connection between the terminal device and the network device. The method comprises: when the terminal device triggers a cell reselection operation, determining a serving cell of the terminal device according to a configuration of an initial paging area of the terminal device.

What is claimed is: 
     
         1 . A method for cell reselection, applied to a terminal device, wherein a connection between the terminal device and a network device is in a disconnected state, and the network device retains context information of the terminal device, and the context information is used for establishing the connection between the terminal device and the network device;
 the method comprises:   when the terminal device triggers a cell reselection operation, determining a serving cell of the terminal device according to a configuration situation of an initial paging area of the terminal device.   
     
     
         2 . The method of  claim 1 , wherein determining the serving cell of the terminal device according to the configuration situation of the initial paging area of the terminal device comprises:
 when the terminal device is configured with the initial paging area and the cell of at least one first cell in the initial paging area satisfies a cell selection criterion, S criterion, determining, by the terminal device, the serving cell in the at least one first cell.   
     
     
         3 . The method of  claim 2 , wherein determining, by the terminal device, the serving cell in the at least one first cell, comprises:
 when the at least one first cell is a plurality of first cells, determining, by the terminal device, the serving cell in the plurality of first cells according to frequency priority information corresponding to each first cell and/or cell quality information of each first cell.   
     
     
         4 . The method of  claim 1 , wherein determining the serving cell of the terminal device according to the configuration situation of the initial paging area of the terminal device comprises:
 when the terminal device is configured with the initial paging area and each cell in the initial paging area does not satisfy the cell selection criterion, S criterion, determining, by the terminal device, the serving cell in at least one second cell, wherein the initial paging area does not overlap with the at least one second cell.   
     
     
         5 . The method of  claim 1 , wherein determining the serving cell of the terminal device according to the configuration situation of the initial paging area of the terminal device comprises:
 when the network device does not configure the initial paging area for the terminal device, determining, by the terminal device, the serving cell in at least one third cell, wherein the at least one third cell is a cell measured by the terminal device.   
     
     
         6 . The method of  claim 1 , before determining the serving cell of the terminal device, the method further comprises:
 receiving, by the terminal device, a system message or a network configuration message, wherein the system message or the network configuration message comprises information for determining the serving cell of the terminal device.   
     
     
         7 . The method of  claim 1 , wherein
 a frequency priority of each cell in the initial paging area is higher than that of a cell outside the initial paging area.   
     
     
         8 . The method of  claim 1 , wherein,
 a cell where the terminal device resides in the initial paging area has a highest frequency priority.   
     
     
         9 . A terminal device, wherein a connection between the terminal device and a network device is in a disconnected state, and the network device retains context information of the terminal device, the context information is used for establishing the connection between the terminal device and the network device;
 the terminal device comprises: a processor and a transceiver, wherein   the processor is configured to determine a serving cell of the terminal device according to a configuration situation of an initial paging area of the terminal device when a cell reselection operation is triggered.   
     
     
         10 . The terminal device of  claim 9 , wherein the processor is configured to:
 when the terminal device is configured with the initial paging area and the cell of at least one first cell in the initial paging area satisfies a cell selection criterion, S criterion, determine the serving cell in the at least one first cell.   
     
     
         11 . The terminal device of  claim 10 , wherein the processor is configured to:
 when the at least one first cell is a plurality of first cells, determine the serving cell in the plurality of first cells according to frequency priority information corresponding to each first cell and/or cell quality information of each first cell.   
     
     
         12 . The terminal device of  claim 9 , wherein the processor is configured to:
 when the terminal device is configured with the initial paging area and each cell in the initial paging area does not satisfy the cell selection criterion, S criterion, determine the serving cell in at least one second cell, wherein the initial paging area does not overlap with the at least one second cell.   
     
     
         13 . The terminal device of  claim 9 , wherein the processor is configured to:
 when the network device does not configure the initial paging area for the terminal device, determine, by the terminal device, the serving cell in at least one third cell, wherein the at least one third cell is a cell measured by the terminal device.   
     
     
         14 . The terminal device of  claim 9 , wherein:
 the transceiver is configured to receive a system message or a network configuration message before the serving cell of the terminal device is determined, wherein the system message or the network configuration message comprises information for determining the serving cell of the terminal device.   
     
     
         15 . The terminal device of  claim 9 , wherein,
 a frequency priority of each cell in the initial paging area is higher than that of a cell outside the initial paging area.   
     
     
         16 . The terminal device of  claim 9 , wherein,
 a cell where the terminal device resides in the initial paging area has a highest frequency priority.   
     
     
         17 . A chip, comprising an input interface, an output interface, at least one processor, and a memory, wherein the processor is used for executing codes in the memory to implement the method of  claim 1 .