Heterogeneous network (HETNET) user equipment (UE) radio resource management (RRM) measurements

• US 9,282,472 B2
• Filed: 03/27/2013
• Issued: 03/08/2016
• Est. Priority Date: 04/13/2010
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Ji, Tingfang, Song, Osok, Damnjanovic, Aleksandar, Gaal, Peter, Luo, Tao, Malladi, Durga Prasad
• Primary Examiner(s): Ajibade Akonai, Olumide T
• Application Number:
  US13/851,815
• Publication Number:
  US 20130229933A1
• Time in Patent Office: 1,077 Days
• Field of Search: 455/448, 455/449, 455/450, 455/451, 455/452.1, 455/452.2, 455/453, 455/509, 455/422.1, 455/63.1, 370/252, 370/328, 370/329, 370/330, 370/336, 370/347
• US Class Current: 1/1
• CPC Class Codes: H04J 11/0023 Interference mitigation or co-ordination direct sequence spread spectrum [DSSS] systems H04B1/7097; frequency hopping H04B1/713; allocation criteria for ingress interference avoidance H04L5/0062; frequency allocation criteria for requirements on out-of-channel emissions H04L5/0066; arrangements for removing intersymbol interference or baseband equalisers H04L25/03006; peak power aspects in multicarrier modulation H04L27/2614; power management H04W52/00; traffic scheduling H04W72/54, H04W72/541
• CPC Class Codes: H04J 11/005 of intercell interference
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: H04W 16/02 Resource partitioning among network components, e.g. reuse partitioning
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 36/0088 Scheduling hand-off measurements
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B
• CPC Class Codes: H04W 84/047 using dedicated repeater stations

Abstract

Methods and apparatus for performing radio resource management (RRM) measurements in a heterogeneous network (HetNet) are provided in an effort to prevent failure of RRM measurement procedures in a dominant interference scenario. Several alternatives are provided for determining particular resources (e.g., subframes) to use for performing the RRM measurements, wherein the particular resources are based on cooperative resource partitioning between cells of the HetNet, wherein the cells may be of different types (e.g., macro, pico, or femto cells). These alternatives include, for example: (1) intra-frequency or intra-RAT (radio access technology) alternatives, which may involve transmitting resource partitioning information (RPI) in or deriving non-serving cell RPI based on the serving cell'"'"'s RPI, as well as (2) inter-frequency or inter-RAT alternatives, where the RRM measurements may be performed during a measurement gap.

Claims

1. A method for wireless communications at a user equipment (UE), comprising:

receiving transmissions from a plurality of cells, at the UE, the transmissions occurring during a plurality of subframes, and the plurality of cells including a serving cell and one or more non-serving cells;

determining a set of subframes, from the plurality of subframes, to include in a radio resource measurement, the set of subframes being based on a subframe resource allocation map for the plurality of cells, the subframe resource allocation map identifying at least one protected subframe among the plurality of cells; and

performing the radio resource measurement for the determined set of subframes.

2. The method of claim 1, wherein the determining comprises receiving, from the serving cell, information regarding the subframe resource allocation map for both the serving cell and the one or more non-serving cells.

3. The method of claim 2, wherein a neighbor list from the serving cell carries the information in a system information block (SIB).

4. The method of claim 1, wherein the determining comprises:

receiving, from the serving cell, information regarding the subframe resource allocation map for the serving cell; and

deriving the subframe resource allocation map for the one or more non-serving cells based on the information for the serving cell.

5. The method of claim 4, wherein the deriving comprises considering the subframe resource allocation map for the one or more non-serving cells to be the same as the subframe resource allocation map for the serving cell.

6. The method of claim 4, wherein the deriving comprises performing blind detection based on performing the radio resource measurement for the determined set of subframes.

7. The method of claim 1, wherein the determining comprises receiving, from the one or more non-serving cells, information regarding the subframe resource allocation map for the one or more non-serving cells.

8. The method of claim 1, wherein the radio resource measurement is a measurement of reference signal receive quality (RSRQ) based on a received signal strength indicator (RSSI) of the determined set of subframes and on a reference signal receive power (RSRP) of an interfering cell from among the one or more non-serving cells.

9. The method of claim 1, wherein the radio resource measurement comprises an intra-frequency radio resource measurement associated with the serving cell or the one or more non-serving cells.

10. An apparatus for wireless communications, comprising:

means for receiving transmissions from a plurality of cells, at the UE, the transmissions occurring during a plurality of subframes, and the plurality of cells including a serving cell and one or more non-serving cells;

means for determining a set of subframes, from the plurality of subframes, to include in a radio resource measurement, the set of subframes being based on a subframe resource allocation map for the plurality of cells, the subframe resource allocation map identifying at least one protected subframe among the plurality of cells; and

means for performing the radio resource measurement for the determined set of subframes.

11. The apparatus of claim 10, wherein the means for determining is configured to receive, from the serving cell, information regarding the subframe resource allocation map for both the serving cell and the one or more non-serving cells.

12. The apparatus of claim 11, wherein a neighbor list from the serving cell carries the information in a system information block (SIB).

13. The apparatus of claim 10, wherein the means for determining is configured to:

receive, from the serving cell, information regarding the subframe resource allocation map for the serving cell; and

derive the subframe resource allocation map for the one or more non-serving cells based on the information for the serving cell.

14. The apparatus of claim 13, wherein deriving the subframe resource allocation map for the one or more non-serving cells comprises considering the subframe resource allocation map for the one or more non-serving cells to be the same as the RPI for the serving cell.

15. The apparatus of claim 13, wherein deriving the subframe resource allocation map for the one or more non-serving cells comprises performing blind detection based on performing the radio resource measurement for the determined set of subframes.

16. The apparatus of claim 10, wherein the means for determining is configured to receive, from the one or more non-serving cells, information regarding the subframe resource allocation map for the one or more non-serving cells.

17. The apparatus of claim 10, wherein the radio resource measurement is a measurement of reference signal receive quality (RSRQ) based on a received signal strength indicator (RSSI) of the determined set of subframes and on a reference signal receive power (RSRP) of an interfering cell from among the one or more non-serving cells.

18. The apparatus of claim 10, wherein the radio resource measurement comprises an intra-frequency radio resource measurement associated with the serving cell or the one or more non-serving cells.

19. An apparatus for wireless communications, comprising:

a receiver configured to receive transmissions from a plurality of cells, at the UE, the transmissions occurring during a plurality of subframes, and the plurality of cells including a serving cell and one or more non-serving cells; and

at least one processor configured to;

determine a set of subframes, from the plurality of subframes, to include in a radio resource measurement, the set of subframes being based on a subframe resource allocation map for the plurality of cells, the subframe resource allocation map identifying at least one protected subframe among the plurality of cells; and

perform the radio resource measurement for the determined set of subframes.

20. The apparatus of claim 19, wherein the at least one processor is configured to determine the set of subframes by receiving, from the serving cell, information regarding the subframe resource allocation map for both the serving cell and the one or more non-serving cells.

21. The apparatus of claim 20, wherein a neighbor list from the serving cell carries the information in a system information block (SIB).

22. The apparatus of claim 19, wherein the at least one processor is configured to determine the set of subframes by:

receiving, from the serving cell, information regarding the subframe resource allocation map for the serving cell; and

deriving the subframe resource allocation map for the one or more non-serving cells based on the information for the serving cell.

23. The apparatus of claim 22, wherein the deriving comprises considering the subframe resource allocation map for the one or more non-serving cells comprises considering the subframe resource allocation map for the one or more non-serving cells to be the same as the RPI for the serving cell.

24. The apparatus of claim 22, wherein the deriving comprises performing blind detection based on performing the radio resource measurement for the determined set of subframes.

25. The apparatus of claim 19, wherein the at least one processor is configured to determine the set of subframes by receiving, from the one or more non-serving cells, information regarding the subframe resource allocation map for the one or more non-serving cells.

26. The apparatus of claim 19, wherein the radio resource measurement is a measurement of reference signal receive quality (RSRQ) based on a received signal strength indicator (RSSI) of the determined set of subframes and on a reference signal receive power (RSRP) of an interfering cell from among the one or more non-serving cells.

27. The apparatus of claim 19, wherein the radio resource measurement comprises an intra-frequency radio resource measurement associated with the serving cell or the one or more non-serving cells.

28. A non-transitory computer-readable medium having computer executable code stored thereon for:

receiving transmissions from a plurality of cells, at the UE, the transmissions occurring during a plurality of subframes, and the plurality of cells including a serving cell and one or more non-serving cells;

determining a set of subframes, from the plurality of subframes, to include in a radio resource measurement, the set of subframes being based on a subframe resource allocation map for the plurality of cells, the subframe resource allocation map identifying at least one protected subframe among the plurality of cells; and

performing the radio resource measurement for the determined set of subframes.

29. The computer-readable medium of claim 28, wherein the determining comprises receiving, from the serving cell, information regarding the subframe resource allocation map for both the serving cell and the one or more non-serving cells.

30. The computer-readable medium of claim 29, wherein a neighbor list from the serving cell carries the information in a system information block (SIB).

31. The computer-readable medium of claim 28, wherein the determining comprises:

receiving, from the serving cell, information regarding the subframe resource allocation map for the serving cell; and

deriving the subframe resource allocation map for the one or more non-serving cells based on the information for the serving cell.

32. The computer-readable medium of claim 31, wherein the deriving comprises considering the subframe resource allocation map for the one or more non-serving cells comprises considering the subframe resource allocation map for the one or more non-serving cells to be the same as the RPI for the serving cell.

33. The computer-readable medium of claim 31, wherein the deriving comprises performing blind detection based on performing the radio resource measurement for the determined set of subframes.

34. The computer-readable medium of claim 28, wherein the determining comprises receiving, from the one or more non-serving cells, information regarding the subframe resource allocation map for the one or more non-serving cells.

35. The computer-readable medium of claim 28, wherein the radio resource measurement is a measurement of reference signal receive quality (RSRQ) based on a received signal strength indicator (RSSI) of the determined set of subframes and on a reference signal receive power (RSRP) of an interfering cell from among the one or more non-serving cells.

36. The computer-readable medium of claim 28, wherein the radio resource measurement comprises an intra-frequency radio resource measurement associated with the serving cell or the one or more non-serving cells.

37. A method for wireless communications, comprising:

determining, at a first base station, a measurement gap associated with a second base station for an inter-frequency or an inter-RAT (radio access technology) radio resource measurement;

generating, at the first base station, a subframe resource allocation map identifying subframe usage among at least the first and second base stations, wherein the subframe resource allocation map includes at least one subframe designated for radio resource measurements of the first base station; and

transmitting subframes from the first base station according to the subframe resource allocation map, wherein the at least one subframe designated for radio resource measurements of the first base station falls within the measurement gap associated with the second base station.

38. The method of claim 37, wherein the at least one subframe comprises more than 2 subframes.

39. The method of claim 37, wherein the determining comprises receiving an indication of the measurement gap via a backhaul between the first and second base stations.

40. An apparatus for wireless communications, comprising:

means for determining a measurement gap associated with a base station for an inter-frequency or an inter-RAT (radio access technology) radio resource measurement;

means for generating a subframe resource allocation map identifying subframe usage among at least the apparatus and the base station, wherein the subframe resource allocation map includes at least one subframe designated for radio resource measurements of the apparatus; and

means for transmitting subframes from the apparatus according to the subframe resource allocation map, wherein the at least one subframe designated for radio resource measurements of the apparatus falls within the measurement gap associated with the base station.

41. The apparatus of claim 40, wherein the at least one subframe comprises more than 2 subframes.

42. The apparatus of claim 40, wherein the means for determining is configured to receive an indication of the measurement gap via a backhaul between the apparatus and the base station.

43. An apparatus for wireless communications, comprising:

at least one processor configured to;

determine a measurement gap associated with a base station for an inter-frequency or an inter-RAT (radio access technology) radio resource measurement; and

generate a subframe resource allocation map identifying subframe usage among at least the apparatus and the base station, wherein the subframe resource allocation map includes at least one subframe designated for radio resource measurements of the apparatus; and

a transmitter configured to transmit subframes from the apparatus according to the subframe resource allocation map, wherein the at least one subframe designated for radio resource measurements of the apparatus falls within the measurement gap associated with the base station.

44. The apparatus of claim 43, wherein the at least one subframe comprises more than 2 subframes.

45. The apparatus of claim 43, wherein the at least one processor is configured to determine the measurement gap by receiving an indication of the measurement gap via a backhaul between the apparatus and the base station.

46. A non-transitory computer-readable medium having computer executable code stored thereon for:

determining, at a first base station, a measurement gap associated with a second base station for an inter-frequency or an inter-RAT (radio access technology) radio resource measurement;

generating, at the first base station a subframe resource allocation map identifying subframe usage among at least the first and second base stations, wherein the subframe resource allocation map includes at least one subframe designated for radio resource measurements of the first base station; and

transmitting subframes from the first base station according to the subframe resource allocation map, wherein the at least one subframe designated for radio resource measurements of the first base station falls within the measurement gap associated with the second base station.

47. The computer-readable medium of claim 46, wherein the at least one subframe comprises more than 2 subframes.

48. The computer-readable medium of claim 46, wherein the determining comprises receiving an indication of the measurement gap via a backhaul between the first and second base stations.