Paging in Heterogeneous Networks with Discontinuous Reception

• US 20130114484A1
• Filed: 07/10/2012
• Published: 05/09/2013
• Est. Priority Date: 11/04/2011
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Research In Motion Limited (Blackberry Limited)
• Inventors: Suzuki, Takashi, Cai, Zhijun
• Granted Patent: US 8,964,672 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 68/025 Indirect paging
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for operating a UE in a wireless communications network is provided. The method comprises attempting, by a UE configured to operate in a DRX mode and with time domain measurement resource restrictions, to read a paging message in a paging occasion in a restricted subframe during DRX active time.

Claims

1. A method for operating a user equipment (UE) in a wireless communications network, the method comprising:

attempting, by a UE configured to operate in a discontinuous reception (DRX) mode and with time domain measurement resource restrictions, to read a paging message in a paging occasion in a restricted subframe during DRX active time.

2. The method of claim 1, further comprising estimating, by the UE, available paging occasions based on paging control channel configurations and configured DRX parameters and restricted subframe patterns.

3. The method of claim 1, further comprising calculating, by the UE, the number of paging occasions to read by assuming that the probability of a target paging occasion being within the active time is a predetermined number.

4. The method of claim 1, further comprising calculating, by the UE, the number of paging occasions to read by assuming that the probability of a target paging occasion being within the active time is proportional to current data activity.

5. A user equipment (UE) comprising:

a processor configured such that the UE attempts to read a paging message in a paging occasion in a restricted subframe during discontinuous reception (DRX) active time, wherein the UE is configured to operate in DRX mode and with time domain measurement resource restrictions.

6. The UE of claim 5, wherein the UE estimates available paging occasions based on paging control channel configurations and configured DRX parameters and restricted subframe patterns.

7. The UE of claim 5, wherein the UE calculates the number of paging occasions to read by assuming that the probability of a target paging occasion being within the active time is a predetermined number.

8. The UE of claim 5, wherein the UE calculates the number of paging occasions to read by assuming that the probability of a target paging occasion being within the active time is proportional to current data activity.

9. A method for operating a network element in a wireless communications network, the method comprising:

configuring, by the network element, a discontinuous reception (DRX) cycle to 5*2ⁿ subframes and a DRX start offset that aligns on-duration periods to paging occasions that are protected by restricted subframes, wherein the network element is configured to utilize DRX and time domain measurement resource restrictions.

10. The method of claim 9, wherein the DRX start offset is set to 10*m+9 (m=0, 1, . . . floor((5*2ⁿ-9)/10).

11. The method of claim 9, wherein the network element is a victim node in a heterogeneous network.

12. The method of claim 11, wherein the victim node is at least one of:

a pico cell;

a femto cell;

a relay;

or

a macro cell.

13. A network element in a wireless communications network, the network element comprising:

a processor configured such that the network element configures a discontinuous reception (DRX) cycle to 5*2ⁿ subframes and a DRX start offset that aligns on-duration periods to paging occasions that are protected by restricted subframes, wherein the network element is configured to utilize DRX and time domain measurement resource restrictions.

14. The network element of claim 13, wherein the DRX start offset is set to 10*m+9 (m=0, 1, . . . floor((5*2ⁿ-9)/10).

15. The network element of claim 13, wherein the network element is a victim node in a heterogeneous network.

16. The network element of claim 15, wherein the victim node is at least one of:

a pico cell;

a femto cell;

a relay;

or

a macro cell.

17. A method for operating a user equipment (UE) in a wireless heterogeneous network, the method comprising:

attempting, by the UE, to read a paging radio network temporary identifier in selected subframes at a selected time interval; and

activating, by the UE, its receiver to receive transmissions from at least one of an underlay cell and an overlay cell during an active time,

wherein the subframes are selected by the network to promote intercell interference coordination via a coordination method, the coordination method being one of a backhaul signaling technique or an almost blank subframe technique.

18. The method of claim 17, wherein the selected time interval duration is one of a value allocated to the UE by the network or a broadcast value.

19. The method of claim 17, further comprising receiving, by the UE, a configuration, wherein the configuration includes a DRX interval set to 5*2ⁿ subframes and a start offset that substantially results in the UE reading paging messages during the selected subframes and the UE not seeking to read paging messages in other subframes and within an on-duration, and wherein n is a positive integer.