Method and apparatus for enabling channel and interference estimations in macro/RRH system

• US 9,544,108 B2
• Filed: 12/23/2011
• Issued: 01/10/2017
• Est. Priority Date: 02/11/2011
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Geirhofer, Stefan, Ji, Tingfang, Gaal, Peter, Luo, Tao, Chen, Wanshi, Montojo, Juan
• Primary Examiner(s): Patel, Chandrahas
• Assistant Examiner(s): TRUONG, LAN-HUONG
• Application Number:
  US13/336,599
• Publication Number:
  US 20120207043A1
• Time in Patent Office: 1,845 Days
• Field of Search: 370/322, 370/332, 370/443, 370/508, 370/352
• US Class Current: 1/1
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling

Abstract

Aspects disclosed herein relate to channel and interference estimations in a multiple transmission point environment including an eNB and RRHs. In the disclosed aspects, one or more transmission points can signal to a UE to measure channel state conditions based on a first and a second resource pattern. The UE may receive the signaling and perform interference estimation based at least in part on the first resource pattern, and channel estimation based at least in part on the second resource pattern. The UE may generate a channel state report based on the interference and channel estimations, and transmit the channel state report to a transmission point. The eNB may employ the received channel state report in scheduling one or more resources for use by the UE, and may select or adjust network traffic on the first and the second resource pattern, to affect the resulting channel and interference estimation.

Claims

1. A method of wireless communications, comprising:

signaling to a user equipment (UE), from a serving cell, to measure channel state conditions based on a first resource pattern, a second resource pattern, and a third resource pattern, the first resource pattern identifying resources for a channel estimation on which a first transmission point located within the serving cell transmits reference signals and the second resource pattern identifying resources for an interference estimation on which a second transmission point located within the serving cell transmits the reference signals and on which the first transmission point does not transmit the reference signals, wherein

the first resource pattern identifies the resources for the channel estimation for one or more signals from one or more coordinating transmission points,

the second resource pattern is a muted resource pattern that collides with a data transmission from the first transmission point to the UE, and

the third resource pattern identifies resources for an interference estimation for one or more signals from outside the one or more coordinating transmission points;

receiving a channel state condition report from the UE based, at least in part, on measurements obtained using the first resource pattern and second resource pattern; and

scheduling one or more resources for use by the UE based on the received channel state condition report.

2. The method of claim 1, wherein the third resource pattern corresponds to one or more common reference signal (CRS) patterns of the one or more coordinating transmission points.

3. The method of claim 1, wherein the signaling to the UE to measure channel state conditions further comprises signaling one or more of identifiers (IDs) corresponding to the one or more coordinating transmission points.

4. The method of claim 1, further comprising coordinating transmissions from the at least one of the one or more coordinating transmission points such that interference observed by the UE on the second resource pattern from the at least one of the one or more transmission points corresponds to expected transmissions by the one or more transmission points during transmissions to the UE.

5. The method of claim 1, wherein the channel state conditions include channel and interference estimation information.

6. The method of claim 5, wherein the interference estimation is based, at least in part, on the first resource pattern resources as filtered to remove or minimize the presence of one or more pilot signals.

7. The method of claim 1, wherein the first resource pattern is a first channel state information reference signal (CSI-RS) pattern, and wherein the second resource pattern is a second CSI-RS pattern.

8. The method of claim 1, further comprising:

semi-statically configuring at least one of the first resource pattern, the second resource pattern or the third resource pattern for signaling to the UE to measure the channel state conditions.

9. The method of claim 1, wherein:

the first resource pattern comprises a non-muted CSI-RS pattern where the first transmission point transmits on the non-muted CSI-RS pattern, and

the second resource pattern comprises a muted CSI-RS pattern where the first transmission point does not transmit on the muted CSI-RS pattern.

10. A method of wireless communications, comprising:

receiving, by a user equipment (UE), signaling of a first resource pattern, a second resource pattern, and a third resource pattern from a serving cell, the first resource pattern identifying resources for a channel estimation on which a first transmission point located within the serving cell transmits reference signals and the second resource pattern identifying resources for an interference estimation on which a second transmission point located within the serving cell transmits the reference signals and on which the first transmission point does not transmit the reference signals, wherein the second resource pattern is a muted resource pattern that collides with a data transmission from the first transmission point to the UE, and wherein the first and second resource patterns comprise channel state information reference signal (CSI-RS) patterns, respectively;

performing channel estimation based at least in part on the first resource pattern, and interference estimation for one or more signals from outside one or more transmission points based at least in part on the second resource pattern and the third resource pattern;

generating a channel state condition report based on the interference estimation and the channel estimation; and

transmitting the channel state condition report to one or more transmission points.

11. The method of claim 10, wherein the third resource pattern corresponds to one or more common reference signal (CRS) patterns corresponding to the one or more transmission points.

12. The method of claim 10, wherein the performing interference estimation further comprises:

measuring interference on a muted CSI-RS pattern of the first and second resource patterns where at least one of the one or more transmission points are not transmitting on the muted CSI-RS pattern, and wherein a non-muted CSI-RS pattern of the first and second resources patterns is filtered to remove or minimize the presence of one or more pilot signals.

13. The method of claim 10, wherein:

the first resource pattern comprises a non-muted CSI-RS pattern where the first transmission point transmits on the non-muted CSI-RS pattern, and

the second resource pattern comprises a muted CSI-RS pattern where the first transmission point does not transmit on the muted CSI-RS pattern.

14. An apparatus for wireless communication, comprising:

means for signaling to a user equipment (UE), from a serving cell, to measure channel state conditions based on a first resource pattern, a second resource pattern, and a third resource pattern, the first resource pattern identifying resources for a channel estimation on which a first transmission point located within the serving cell transmits reference signals and the second resource pattern identifying resources for an interference estimation on which a second transmission point located within the serving cell transmits the reference signals and on which the first transmission point does not transmit the reference signals, wherein

the first resource pattern identifies the resources for the channel estimation for one or more signals from one or more coordinating transmission points,

the second resource pattern is a muted resource pattern that collides with a data transmission from the first transmission point to the UE, and

the third resource pattern identifies resources for an interference estimation for one or more signals from outside the one or more coordinating transmission points;

means for receiving a channel state condition report from the UE based, at least in part, on measurements obtained using the first resource pattern and second resource pattern; and

means for scheduling one or more resources for use by the UE based on the received channel state condition report.

15. The apparatus of claim 14, wherein the third resource pattern corresponds to one or more common reference signal (CRS) patterns of the one or more coordinating transmission points.

16. The apparatus of claim 14, wherein the means for signaling to the UE to measure channel state conditions further comprises means for signaling one or more of identifiers (IDs) corresponding to the one or more coordinating transmission points.

17. The apparatus of claim 16, further comprising means for coordinating transmissions from the at least one of the one or more coordinating transmission points such that interference observed by the UE on the second resource pattern from the at least one of the one or more transmission points corresponds to expected transmissions by the one or more transmission points during transmissions to the UE.

18. The apparatus of claim 14, wherein the channel conditions include channel and interference estimation information.

19. The apparatus of claim 18, wherein the interference estimation is based, at least in part, on the first resource pattern resources as filtered to remove or minimize the presence of one or more pilot signals.

20. The apparatus of claim 14, wherein the first resource pattern is a first channel state information reference signal (CSI-RS) pattern, and wherein the second resource pattern is a second CSI-RS pattern.

21. The apparatus of claim 14, further comprising:

means for semi-statically configuring at least one of the first resource pattern, the second resource pattern, or the third resource pattern for signaling to the UE to measure the channel state conditions.

22. A apparatus for wireless communications, comprising:

means for receiving, by a user equipment (UE), signaling of a first resource pattern, a second resource pattern, and a third resource pattern from a serving cell, the first resource pattern identifying resources for a channel estimation on which a first transmission point located within the serving cell transmits reference signals and the second resource pattern identifying resources for an interference estimation on which a second transmission point located within the serving cell transmits the reference signals and on which the first transmission point does not transmit the reference signals, wherein the second resource pattern is a muted resource pattern that collides with a data transmission from the first transmission point to the UE, and wherein the first and second resource patterns comprise channel state information reference signal (CSI-RS) patterns, respectively;

means for performing channel estimation based at least in part on the first resource pattern, and means for performing interference estimation for one or more signals from outside one or more transmission points based at least in part on the second resource pattern and the third resource pattern;

means for generating a channel state condition report based on the interference estimation and the channel estimation; and

means for transmitting the channel state condition report to the one or more transmission points.

23. The apparatus of claim 22, wherein the third resource pattern corresponds to one or more common reference signal (CRS) patterns corresponding to the one or more transmission points.

24. The apparatus of claim 22, wherein the means for performing interference estimation further comprises:

means for measuring interference on a muted CSI-RS pattern of the first and second resource patterns where at least one of the one or more transmission points are not transmitting on the muted CSI-RS pattern, and wherein a non-muted CSI-RS pattern of the first and second resources patterns is filtered to remove or minimize the presence of one or more pilot signals.

25. A non-transitory computer-readable medium storing computer executable code for wireless communication, comprising code for:

signaling to a user equipment (UE), from a serving cell, to measure channel state conditions based on a first resource pattern, a second resource pattern, and a third resource pattern, the first resource pattern identifying resources for a channel estimation on which a first transmission point located within the serving cell transmits reference signals and the second resource pattern identifying resources for an interference estimation on which a second transmission point located within the serving cell transmits the reference signals and on which the first transmission point does not transmit the reference signals, wherein

the first resource pattern identifies the resources for the channel estimation for one or more signals from one or more coordinating transmission points,

the second resource pattern is a muted resource pattern that collides with a data transmission from the first transmission point to the UE, and

the third resource pattern identifies resources for an interference estimation for one or more signals from outside the one or more coordinating transmission points;

receiving a channel state condition report from the UE based, at least in part, on measurements obtained using the first resource pattern and second resource pattern; and

scheduling one or more resources for use by the UE based on the received channel state condition report.

26. The non-transitory computer-readable medium of claim 25, wherein the third resource pattern corresponds to one or more common reference signal (CRS) patterns of the one or more coordinating transmission points.

27. The non-transitory computer-readable medium of claim 25, wherein the code for signaling to the UE to measure channel state conditions further comprises code for signaling one or more of identifiers (IDs) corresponding to the one or more coordinating transmission points.

28. The non-transitory computer-readable medium of claim 27, further comprising code for coordinating transmissions from the at least one of the one or more coordinating transmission points such that interference observed by the UE on the second resource pattern from the at least one of the one or more transmission points corresponds to expected transmissions by the one or more transmission points during transmissions to the UE.

29. The non-transitory computer-readable medium of claim 25, wherein the channel conditions include channel and interference estimation information.

30. The non-transitory computer-readable medium of claim 29, wherein the interference estimation is based, at least in part, on the first resource pattern resources as filtered to remove or minimize the presence of one or more pilot signals.

31. The non-transitory computer-readable medium of claim 25, wherein the first resource pattern is a first channel state information reference signal (CSI-RS) pattern, and wherein the second resource pattern is a second CSI-RS pattern.

32. The non-transitory computer-readable medium of claim 25, further comprising code for:

semi-statically configuring at least one of the first resource pattern, the second resource pattern, or the third resource pattern for signaling to the UE to measure the channel state conditions.

33. A non-transitory computer-readable medium storing computer executable code for wireless communication, comprising code for:

receiving, by a user equipment (UE), signaling of a first resource pattern, a second resource pattern, and a third resource pattern from a serving cell, the first resource pattern identifying resources for a channel estimation on which a first transmission point located within the serving cell transmits reference signals and the second resource pattern identifying resources for an interference estimation on which a second transmission point located within the serving cell transmits the reference signals and on which the first transmission point does not transmit the reference signals, wherein the second resource pattern is a muted resource pattern that collides with a data transmission from the first transmission point to the UE, and wherein the first and second resource patterns comprise channel state information reference signal (CSI-RS) patterns, respectively;

performing channel estimation based at least in part on the first resource pattern, and interference estimation for one or more signals from outside one or more transmission points based at least in part on the second resource pattern and the third resource pattern;

generating a channel state condition report based on the interference estimation and the channel estimation; and

transmitting the channel state condition report to the one or more transmission points.

34. The non-transitory computer-readable medium of claim 33, wherein the third resource pattern corresponds to one or more common reference signal (CRS) patterns corresponding to the one or more transmission points.

35. The non-transitory computer-readable medium of claim 33, further comprising code for measuring interference on a muted CSI-RS pattern of the first and second resource patterns where at least one of the one or more transmission points are not transmitting on the muted CSI-RS pattern, and wherein a non-muted CSI-RS pattern of the first and second resources patterns is filtered to remove or minimize the presence of one or more pilot signals.

36. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory, the at least one processor configured to;

signal to a user equipment (UE), from a serving cell, to measure channel state conditions based on a first resource pattern, a second resource pattern, and a third resource pattern, the first resource pattern identifying resources for a channel estimation on which a first transmission point located within the serving cell transmits reference signals and the second resource pattern identifying resources for an interference estimation on which a second transmission point located within the serving cell transmits the reference signals and on which the first transmission point does not transmit the reference signals, wherein

the first resource pattern identifies the resources for the channel estimation for one or more signals from one or more coordinating transmission points,

the second resource pattern is a muted resource pattern that collides with a data transmission from the first transmission point to the UE, and

the third resource pattern identifies resources for an interference estimation for one or more signals from outside the one or more coordinating transmission points;

receive a channel state condition report from the UE based, at least in part, on measurements obtained using the first resource pattern and second resource pattern; and

schedule one or more resources for use by the UE based on the received channel state condition report.

37. The apparatus of claim 36, wherein the third resource pattern corresponds to one or more common reference signal (CRS) patterns of the one or more coordinating transmission points.

38. The apparatus of claim 36, wherein the at least one processor is further configured to signal one or more of identifiers (IDs) corresponding to the one or more coordinating transmission points.

39. The apparatus of claim 38, wherein the at least one processor is further configured to coordinate transmissions from the at least one of the one or more coordinating transmission points such that interference observed by the UE on the second resource pattern from the at least one of the one or more transmission points corresponds to expected transmissions by the one or more transmission points during transmissions to the UE.

40. The apparatus of claim 36, wherein the channel conditions include channel and interference estimation information.

41. The apparatus of claim 40, wherein the interference estimation is based, at least in part, on the first resource pattern resources as filtered to remove or minimize the presence of one or more pilot signals.

42. The apparatus of claim 36, wherein the first resource pattern is a first channel state information reference signal (CSI-RS) pattern, and wherein the second resource pattern is a second CSI-RS pattern.

43. The apparatus of claim 36, wherein the at least one processor is further configured to:

semi-statically configuring at least one of the first resource pattern, the second resource pattern, or the third resource pattern for signaling to the UE to measure the channel state conditions.

44. An apparatus for wireless communications, comprising:

a memory; and

at least one processor coupled to the memory, the at least one processor configured to;

receive signaling of a first resource pattern, a second resource pattern, and a third resource pattern from a serving cell, the first resource pattern identifying resources for a channel estimation on which a first transmission point located within the serving cell transmits reference signals and the second resource pattern identifying resources for an interference estimation on which a second transmission point located within the serving cell transmits the reference signals and on which the first transmission point does not transmit the reference signals, wherein the second resource pattern is a muted resource pattern that collides with a data transmission from the first transmission point to the UE, and wherein the first and second resource patterns comprise channel state information reference signal (CSI-RS) patterns, respectively;

perform channel estimation based at least in part on the first resource pattern, and interference estimation for one or more signals from outside one or more transmission points based at least in part on the second resource pattern and the third resource pattern;

generate a channel state condition report based on the interference estimation and the channel estimation; and

transmit the channel state condition report to the one or more transmission points.

45. The apparatus of claim 44, wherein the third resource pattern corresponds to one or more common reference signal (CRS) patterns corresponding to the one or more transmission points.

46. The apparatus of claim 44, wherein the at least one processor is further configured to:

measure interference on a muted CSI-RS pattern of the first and second resource patterns where at least one of the one or more transmission points are not transmitting on the muted CSI-RS pattern, and wherein a non-muted CSI-RS pattern of the first and second resources patterns is filtered to remove or minimize the presence of one or more pilot signals.