Telecommunications apparatus and methods
A terminal device for use in a wireless telecommunications system comprises a transceiver to perform wireless communication with a base station and to obtain system information defining communication parameters from system information data received from that base station; system information storage; and a controller to detect whether the system information storage already holds at least some of the system information applicable to a newly communicating base station and to control the transceiver to obtain any portions of the system information not already held by the terminal device, in which: the system information comprises a plurality of system information blocks; and the controller is configured to detect parts of a system information block stored by the system information storage which are applicable to the newly communicating base station and to obtain other parts of that system information block as a partial system information block from the newly communicating base station.
1. A method of operation of a terminal device for use in a wireless telecommunications system, the method comprising:
obtaining system information defining communication parameters from system information data received from a base station, the system information comprising a plurality of system information blocks;
storing the system information in memory;
detecting whether the memory already holds at least some of the system information applicable to a newly communicating base station; and
obtaining any portions of the system information not already stored in the memory by detecting parts of a stored system information block which are applicable to the newly communicating base station and obtaining other parts of the system information block as a partial system information block from the newly communicating base station wherein
the system information comprises a master information block, obtained by the terminal device before the terminal device obtains the system information blocks,
the master information block provides one or more parameters for reception of one system information block of the plurality of system information blocks, and
the one system information block provides one or more parameters for reception of one or more further system information blocks of the plurality of system information blocks.
2. The method of claim 1 , further comprising:
determining whether identification data associated with system information received from the newly communicating base station corresponds to identification data associated with system information stored by the memory.
3. The method of claim 1 , further comprising:
storing two or more instances of system information, each instance corresponding to one or more respective base stations.
4. The method of claim 3 , further comprising:
storing two or more distinct instances of system information most recently obtained by the terminal device.
5. The method of claim 1 , wherein the identification data is carried by one or both of the master information block and the one system information block.
6. The method of claim 5 , further comprising:
in response to reception of a first system information block carrying identification data which corresponds to system information stored by the memory, not processing the further system information blocks.
7. The method of claim 2 , further comprising:
storing, as the identification data, a set of one of more base station identifiers applicable to at least respective portions of an instance of stored system information.
8. The method of claim 7 , wherein the base station identifiers comprise one or more selected from the list consisting of:
a cell identifier;
an area identifier;
an information block tag;
a tracking area identifier; and
a public land mobile network identifier.
9. The method of claim 1 , wherein the system information received from a base station defines one or both of:
communication parameters for communication with the base station; and
communication parameters for communicating with other terminal devices operating under the control of communication parameters received from the base station in a device-to-device communication operation.
10. The method of claim 1 , wherein the system information data received from the base station is broadcast by the base station.
11. A user equipment for use in a wireless telecommunications system, the user equipment comprising:
a receiver configured to receive system information defining communication parameters from system information data received from a base station, the system information comprising a plurality of system information blocks;
a memory configured to store the system information; and
a processor configured to
determine whether the memory holds at least some of the system information applicable to a newly communicating base station; and
control the receiver to obtain portions of the system information not already stored in the memory by detecting parts of a stored system information block which are applicable to the newly communicating base station, and obtaining other parts of the system information block as a partial system information block from the newly communicating base station, wherein
the system information comprises a master information block, obtained by the terminal device before the terminal device obtains the system information blocks,
the master information block provides one or more parameters for reception of one system information block of the plurality of system information blocks, and
the one system information block provides one or more parameters for reception of one or more further system information blocks of the plurality of system information blocks.
12. The user equipment of claim 11 , wherein the processor is configured to determine whether identification data associated with system information received from the newly communicating base station corresponds to identification data associated with system information stored by the memory.
13. The user equipment of claim 11 , wherein the memory is configured to store two or more instances of system information, each instance corresponding to one or more respective base stations.
14. The user equipment of claim 13 , wherein the memory is configured to store two or more distinct instances of system information most recently obtained by the terminal device.
15. The user equipment of claim 11 , wherein the identification data is carried by one or both of the master information block and the one system information block.
16. Circuitry for a terminal device for use in a wireless telecommunications system, the circuitry configured to:
obtain system information defining communication parameters from system information received from a base station, the system information comprising a plurality of system information blocks;
store the system information in memory;
detect whether the memory already holds at least some of the system information applicable to a newly communicating base station; and
obtain any portions of the system information not already stored in the memory by detecting parts of a stored system information block which are applicable to the newly communicating base station and obtain other parts of the system information block as a partial system information block from the newly communicating base station, wherein
the system information comprises a master information block, obtained by the terminal device before the terminal device obtains the system information blocks,
the master information block provides one or more parameters for reception of one system information block of the plurality of system information blocks, and
the one system information block provides one or more parameters for reception of one or more further system information blocks of the plurality of system information blocks.