Method and apparatus for determining paging time

1. A method for facilitating a network device's capability to page a user equipment (UE), the method comprising:

determining a System Frame Number (SFN) of a radio frame, wherein the radio frame is designated for carrying a Paging Radio Network Temporary Identifier (P-RNTI) for a paging of the UE by the network device, the radio frame comprising a plurality of radio sub-frames, and the P-RNTI being configured to be transmitted by the network device to the UE in a Physical Downlink Control Channel (PDCCH) within one of the plurality of the radio sub-frames in the radio frame; and

determining a position of the radio sub-frame configured to be used in the transmission of the P-RNTI, wherein the determining the position includes consideration of parameters including an International Mobile Subscriber Identifier (IMSI) of the UE being paged, a Discontinuous Reception (DRX) period length of the UE being paged, and a quantity of radio sub-frames suitable for the paging in the radio frame.

2. The method of claim 1 , wherein the determining the SFN of the radio frame

includes consideration of parameters including a UE identifier of the UE being paged, the DRX period length, a quantity of paging occasions within the DRX period, and the quantity of radio sub-frames suitable for the paging in the radio frame.

3. The method of claim 2 , wherein the UE identifier comprises an identifier related to the IMSI of the UE.

4. The method of claim 2 , wherein the UE identifier is the IMSI of the UE mod a positive integer.

5. The method of claim 1 , wherein the determining the SFN of the radio frame comprises:

determining the SFN according to the following formula:

SFN=(PAGING_DRX_PERIOD div PAGING_OCCASION_NUMBER)* (UE_ID mod PAGING_OCCASION_NUMBER)+ n *PAGING_DRX_PERIOD+Frame Offset

wherein the UE_ID indicates a UE identifier of the UE being paged, the PAGING_DRX_PERIOD indicates the DRX period length, the PAGING_OCCASION_NUMBER indicates a quantity of paging occasions within the DRX period length, the Frame Offset indicates an offset of a frame, and the n is a non-negative integer.

6. The method of claim 1 , wherein the determining the SFN of the radio frame comprises:

determining the SFN according to the following formula:

SFN={(UE_ID div M) mod (PAGING_DRX_PERIOD div PAGING_OCCASION_NUMBER)}* PAGING_OCCASION_NUMBER+ n *PAGING_DRX_PERIOD+Frame Offset

wherein the UE_ID indicates a UE identifier of the UE being paged, the PAGING_DRX_PERIOD indicates the DRX period length, the PAGING_OCCASION_NUMBER indicates a quantity of paging occasions within the DRX period length, the Frame Offset indicates an offset of a frame, the n is a non-negative integer, and the M indicates the quantity of radio sub-frames suitable for the paging in the radio frame.

7. The method of claim 1 , wherein the position of the radio sub-frame is determined according to: (IMSI div Y) mod M, where the IMSI is the IMSI of the UE being paged, the Y is a parameter relating to the DRX period length, and the M is a parameter indicating the quantity of radio sub-frames suitable for the paging in the radio frame.

8. An apparatus, comprising:

a first determining unit, configured to determine a System Frame Number (SFN) of a radio frame, wherein the radio frame is designated for carrying a Paging Radio Network Temporary Identifier (P-RNTI) for a paging of a user equipment (UE) by a network device, the radio frame comprising a plurality of radio sub-frames, the P-RNTI being configured to be transmitted by the network device to the UE in a Physical Downlink Control Channel (PDCCH) within one of the plurality of the radio sub-frames in the radio frame; and

a second determining unit, configured to determine a position of the radio sub-frame configured to be used in the transmission of the P-RNTI, wherein the position is determined by consideration of parameters including an International Mobile Subscriber Identifier (IMSI) of the UE being paged, a Discontinuous Reception (DRX) period length of the UE being paged, and a quantity of radio sub-frames suitable for the paging in the radio frame.

9. The apparatus of claim 8 , wherein

the SFN of the radio frame is determined according to the following formula:

SFN=(PAGING_DRX_PERIOD div PAGING_OCCASION_NUMBER)* (UE_ID mod PAGING_OCCASION_NUMBER)+ n *PAGING_DRX_PERIOD+Frame Offset

wherein the UE_ID indicates a UE identifier of the UE being paged, the PAGING_DRX_PERIOD indicates the DRX period length, the PAGING_OCCASION_NUMBER indicates a quantity of paging occasions within the DRX period length, the Frame Offset indicates an offset of a frame, and the n is a non-negative integer.

10. The apparatus of claim 8 , wherein

the SFN of the radio frame is determined according to the following formula:

SFN={(UE_ID div M) mod (PAGING_DRX_PERIOD div PAGING_OCCASION_NUMBER)}* PAGING_OCCASION_NUMBER+ n *PAGING_DRX_PERIOD+Frame Offset

wherein the UE ID indicates a UE identifier of the UE being paged, the PAGING_DRX_PERIOD indicates the DRX period length, the PAGING_OCCASION_NUMBER indicates a quantity of paging occasions within the DRX period length, the Frame Offset indicates an offset of a frame, the n is a non-negative integer, and the M indicates the quantity of radio sub-frames suitable for the paging in the radio frame.

11. The apparatus of claim 8 , wherein the SFN of the radio frame is determined by consideration of parameters including a UE identifier of the UE being paged, the DRX period length, a quantity of paging occasions within the DRX period length, and the quantity of radio sub-frames suitable for the paging in the radio frame.

12. The apparatus of claim 11 , wherein the UE identifier comprises an identifier related to the IMSI of the UE.

13. The apparatus of claim 11 , wherein the UE identifier is the IMSI of the UE mod a positive integer.

14. The apparatus of claim 8 , wherein the apparatus is incorporated into the UE.

15. The apparatus of claim 8 , wherein the apparatus is incorporated into the network device.

16. The apparatus of claim 8 , wherein the position of the radio sub-frame is determined according to: (IMSI div Y) mod M, where the IMSI is the IMSI of the UE being paged, the Y is a parameter relating to the DRX period length, and the M is a parameter indicating the quantity of radio sub-frames suitable for the paging in the radio frame.

17. A wireless communications apparatus, comprising:

a memory for storing instructions; and

a processor coupled to the memory configured to execute the instructions to allow the apparatus to:

determine a System Frame Number (SFN) of a radio frame, wherein the radio frame is designated for carrying a Paging Radio Network Temporary Identifier (P-RNTI) for a paging of a UE by a network device, the radio frame comprising a plurality of radio sub-frames, the P-RNTI being configured to be transmitted by the network device to the UE in a Physical Downlink Control Channel (PDCCH) within one of the plurality of the radio sub-frames in the radio frame; and

determining a position of the radio sub-frame configured to be used in the transmission of the P-RNTI, wherein the determining the position includes consideration of parameters including an International Mobile Subscriber Identifier (IMSI) of the UE being paged, a Discontinuous Reception (DRX) period length of the UE being paged, and a quantity of radio sub-frames suitable for the paging in the radio frame.

18. The wireless communications apparatus of claim 17 , wherein the position of the radio sub-frame is determined according to: (IMSI div Y) mod M, where the IMSI is the IMSI of the UE being paged, the Y is a parameter relating to the DRX period length, and the M is a parameter indicating the quantity of radio sub-frames suitable for the paging in the radio frame.

19. A mobile communications system, comprising: a network device in communication with a user equipment (UE), wherein

the network device is configured to:

send a Paging Radio Network Temporary Identifier (P-RNTI) to the UE in a Physical Downlink Control Channel (PDCCH) within a radio sub-frame of a radio frame, wherein a paging message is associated with the P-RNTI, the paging message being configured to be transmitted in a Physical Downlink Shared Channel (PDSCH) within the radio sub-frame; and

the UE is configured to:

determine a System Frame Number (SFN) of the radio frame;

determine a position of the radio sub-frame within the radio frame by consideration of parameters including an International Mobile Subscriber Identifier (IMSI) of the UE, a Discontinuous Reception (DRX) period length of the UE, and a quantity of radio sub-frames suitable for paging in the radio frame;

decode the PDCCH within the radio sub-frame;

obtain the P-RNTI in the PDCCH; and

obtain the paging message associated with the P-RNTI.

20. The mobile communications system of claim 19 , wherein the position of the radio sub-frame is determined according to: (IMSI div Y) mod M, where the IMSI is the IMSI of the UE being paged, the Y is a parameter relating to the DRX period length, and the M is a parameter indicating the quantity of radio sub-frames suitable for the paging in the radio frame.