METHOD AND APPARATUS FOR MANAGING DOWNLINK TRANSMISSION POWER IN A HETEROGENEOUS NETWORK

• US 20100323745A1
• Filed: 06/15/2010
• Published: 12/23/2010
• Est. Priority Date: 06/19/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Montojo, Juan, Chen, Wanshi, Khandekar, Aamod Dinkar, Ji, Tingfang
• Granted Patent: US 8,600,424 B2
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/243 taking into account interferences
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
• CPC Class Codes: H04W 52/322 Power control of broadcast channels
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels

Abstract

A method, an apparatus, and a computer program product for wireless communication are provided in which it is determined that a transmission of a first instance of control information in a first control region in a subframe of a first power class eNodeB a non-modified power spectral density (PSD) will result in interference above a threshold with a transmission of a second instance of control information in a second control region in a subframe of a second power class eNodeB, PSD is modified for a portion of at least one of the first or second control regions of at least one of the subframes for at least one of the first power class or second power class eNodeB, and the first instance of control information is transmitted during the control region using the modified PSD for the portion of the first instance of control information.

Claims

1. A method of wireless communication, comprising:

determining a transmission of a first instance of control information in a first control region in a subframe of a first power class eNodeB using a non-modified power spectral density (PSD) will result in interference above a threshold with a transmission of a second instance of control information in a second control region in a subframe of a second power class eNodeB;

modifying the PSD for a portion of at least one of the first or second control regions of at least one of the subframes for at least one of the first power class or second power class eNodeB; and

transmitting the first instance of control information during the control region using the modified PSD for the portion of the first instance of control information.

2. The method of claim 1, wherein the subframe of the first power class eNodeB is a multicast broadcast single frequency network (MBSFN) subframe, and wherein the subframe of the second power class eNodeB is a non-MBSFN subframe.

3. The method of claim 1, wherein the modifying further comprises reducing the PSD for the portion of the first control region of the subframe of the first power class eNodeB.

4. The method of claim 3, wherein the reducing the PSD for the portion further comprises:

reducing the PSD for one or more channels scheduled for transmission during the control region, wherein the one or more channels comprise at least one of a common reference signal (CRS), a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), or a physical downlink control channel (PDCCH).

5. The method of claim 3, wherein the reducing the PSD for the portion further comprises:

scheduling transmission of control channel information for a subframe other than the subframe of the first power class eNodeB that results in interference with the subframe of the second power class eNodeB.

6. The method of claim 1, further comprising:

transmitting a message indicating which one or more of a plurality of subframes is transmitted using the modified PSD, wherein the message is transmitted to a least one of the second power class eNodeB or one or more user equipments (UEs) served by the second power class eNodeB.

7. The method of claim 1, further comprising:

determining transmissions from one or more other first power class eNodeB will result in interference above the threshold with the transmission of the second instance of control information in the second control region in the subframe of the second power class eNodeB; and

prompting at least one of the one or more other first power class eNodeBs to modify the PSD of a transmission a corresponding subframe during the subframe of the first power class eNodeB.

8. The method of claim 7, wherein the at least one of the one or more other first power class eNodeBs modify the PSD of the corresponding subframe using a different PSD modification value than that used by the first power class eNodeB.

9. The method of claim 1, wherein the modifying the PSD further comprises increasing the PSD for the portion of the second control region of the subframe of the second power class eNodeB.

10. The method of claim 1, wherein the first power class eNodeB is a macro cell and the second power class eNodeB is a pico cell.

11. The method of claim 1, wherein the first power class eNodeB is a femto cell and the second power class eNodeB is either a pico cell or macro cell.

12. An apparatus for wireless communication, comprising:

means for determining a transmission of a first instance of control information in a first control region in a subframe of a first power class eNodeB using a non-modified power spectral density (PSD) will result in interference above a threshold with a transmission of a second instance of control information in a second control region in a subframe of a second power class eNodeB;

means for modifying the PSD for a portion of at least one of the first or second control regions of at least one of the subframes for at least one of the first power class or second power class eNodeB; and

means for transmitting the first instance of control information during the control region using the modified PSD for the portion of the first instance of control information.

13. The apparatus of claim 12, wherein the subframe of the first power class eNodeB is a multicast broadcast single frequency network (MBSFN) subframe, and wherein the subframe of the second power class eNodeB is a non-MBSFN subframe.

14. The apparatus of claim 12, wherein the means for modifying further comprises means for reducing the PSD for the portion of the first control region of the subframe of the first power class eNodeB.

15. The apparatus of claim 14, wherein the means for reducing the PSD for the portion further comprises:

means for reducing the PSD for one or more channels scheduled for transmission during the control region, wherein the one or more channels comprise at least one of a common reference signal (CRS), a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), or a physical downlink control channel (PDCCH).

16. The apparatus of claim 14, wherein the means for reducing the PSD for the portion further comprises:

means for scheduling transmission of control channel information for a subframe other than the subframe of the first power class eNodeB that results in interference with the subframe of the second power class eNodeB.

17. The apparatus of claim 12, further comprising:

means for transmitting a message indicating which one or more of a plurality of subframes is transmitted using the modified PSD, wherein the message is transmitted to a least one of the second power class eNodeB or one or more user equipments (UEs) served by the second power class eNodeB.

18. The apparatus of claim 12, further comprising:

means for determining transmissions from one or more other first power class eNodeB will result in interference above the threshold with the transmission of the second instance of control information in the second control region in the subframe of the second power class eNodeB; and

means for prompting at least one of the one or more other first power class eNodeBs to modify the PSD of a transmission of a corresponding subframe during the subframe of the first power class eNodeB.

19. The apparatus of claim 18, wherein the at least one of the one or more other first power class eNodeBs modify the PSD of the corresponding subframe using a different PSD modification value than that used by the first power class eNodeB.

20. The apparatus of claim 12, wherein the means for modifying the PSD further comprises means for increasing the PSD for the portion of the second control region of the subframe of the second power class eNodeB.

21. The apparatus of claim 12, wherein the first power class eNodeB is a macro cell and the second power class eNodeB is a pico cell.

22. The apparatus of claim 12, wherein the first power class eNodeB is a femto cell and the second power class eNodeB is either a pico cell or macro cell.

23. A computer program product, comprising:

a computer-readable medium comprising code for;

determining a transmission of a first instance of control information in a first control region in a subframe of a first power class eNodeB using a non-modified power spectral density (PSD) will result in interference above a threshold with a transmission of a second instance of control information in a second control region in a subframe of a second power class eNodeB;

modifying the PSD for a portion of at least one of the first or second control regions of at least one of the subframes for at least one of the first power class or second power class eNodeB; and

transmitting the first instance of control information during the control region using the modified PSD for the portion of the first instance of control information.

24. The computer program product of claim 23, wherein the subframe of the first power class eNodeB is a multicast broadcast single frequency network (MBSFN) subframe, and wherein the subframe of the second power class eNodeB is a non-MBSFN subframe.

25. The computer program product of claim 23, wherein the computer-readable medium further comprises code for reducing the PSD for the portion of the first control region of the subframe of the first power class eNodeB.

26. The computer program product of claim 25, wherein the computer-readable medium further comprises code for:

reducing the PSD for one or more channels scheduled for transmission during the control region, wherein the one or more channels comprise at least one of a common reference signal (CRS), a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), or a physical downlink control channel (PDCCH).

27. The computer program product of claim 25, wherein the computer-readable medium further comprises code for:

scheduling transmission of control channel information for a subframe other than the subframe of the first power class eNodeB that results in interference with the subframe of the second power class eNodeB.

28. The computer program product of claim 23, wherein the computer-readable medium further comprises code for:

transmitting a message indicating which one or more of a plurality of subframes is transmitted using the modified PSD, wherein the message is transmitted to a least one of the second power class eNodeB or one or more user equipments (UEs) served by the second power class eNodeB.

29. The computer program product of claim 23, wherein the computer-readable medium further comprises code for:

determining transmissions from one or more other first power class eNodeB will result in interference above the threshold with the transmission of the second instance of control information in the second control region in the subframe of the second power class eNodeB; and

prompting at least one of the one or more other first power class eNodeBs to modify the PSD of a transmission a corresponding subframe during the subframe of the first power class eNodeB.

30. The computer program product of claim 29, wherein the at least one of the one or more other first power class eNodeBs modify the PSD of the corresponding subframe using a different PSD modification value than that used by the first power class eNodeB.

31. The computer program product of claim 23, wherein the computer-readable medium further comprises code for increasing the PSD for the portion of the second control region of the subframe of the second power class eNodeB.

32. The computer program product of claim 23, wherein the first power class eNodeB is a macro cell and the second power class eNodeB is a pico cell.

33. The computer program product of claim 23, wherein the first power class eNodeB is a femto cell and the second power class eNodeB is either a pico cell or macro cell.

34. An apparatus for wireless communication, comprising:

a processing system configured to;

determine a transmission of a first instance of control information in a first control region in a subframe of a first power class eNodeB using a non-modified power spectral density (PSD) will result in interference above a threshold with a transmission of a second instance of control information in a second control region in a subframe of a second power class eNodeB;

modify PSD for a portion of at least one of the first or second control regions of at least one of the subframes for at least one of the first power class or second power class eNodeB; and

transmit the first instance of control information during the control region using the modified PSD for the portion of the first instance of control information.

35. The apparatus of claim 34, wherein the subframe of the first power class eNodeB is a multicast broadcast single frequency network (MBSFN) subframe, and wherein the subframe of the second power class eNodeB is a non-MBSFN subframe.

36. The apparatus of claim 34, wherein the processing system is further configured to reduce the PSD for the portion of the first control region of the subframe of the first power class eNodeB.

37. The apparatus of claim 36, wherein the processing system is further configured to:

reduce the PSD for one or more channels scheduled for transmission during the control region, wherein the one or more channels comprise at least one of a common reference signal (CRS), a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), or a physical downlink control channel (PDCCH).

38. The apparatus of claim 36, wherein the processing system is further configured to:

schedule transmission of control channel information for a subframe other than the subframe of the first power class eNodeB that results in interference with the subframe of the second power class eNodeB.

39. The Apparatus of claim 34, wherein the processing system is further configured to:

transmit a message indicating which one or more of a plurality of subframes is transmitted using the modified PSD, wherein the message is transmitted to a least one of the second power class eNodeB or one or more user equipments (UEs) served by the second power class eNodeB.

40. The apparatus of claim 34, wherein the processing system is further configured to:

determine transmissions from one or more other first power class eNodeB will result in interference above the threshold with the transmission of the second instance of control information in the second control region in the subframe of the second power class eNodeB; and

prompt at least one of the one or more other first power class eNodeBs to modify the PSD of a transmission a corresponding subframe during the subframe of the first power class eNodeB.

41. The apparatus of claim 40, wherein the at least one of the one or more other first power class eNodeBs modify the PSD of the corresponding subframe using a different PSD modification value than that used by the first power class eNodeB.

42. The apparatus of claim 34, wherein to modify the PSD, the processing system is configured to increase the PSD for the portion of the second control region of the subframe of the second power class eNodeB.

43. The apparatus of claim 34, wherein the first power class eNodeB is a macro cell and the second power class eNodeB is a pico cell.

44. The apparatus of claim 34, wherein the first power class eNodeB is a femto cell and the second power class eNodeB is either a pico cell or macro cell.