Discovery reference signal transmission window detection and discovery reference signal measurement configuration

• US 10,433,291 B2
• Filed: 02/23/2017
• Issued: 10/01/2019
• Est. Priority Date: 02/26/2016
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Radulescu, Andrei, Patel, Chirag, Luo, Tao, Chendamarai Kannan, Arumugam
• Primary Examiner(s): Qureshi, Afsar M
• Application Number:
  US15/441,222
• Publication Number:
  US 20170251456A1
• Time in Patent Office: 950 Days
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04J 11/0036 at the receiver
• CPC Class Codes: H04L 41/0866 Checking the configuration
• 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 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 48/00 Access restriction access security to prevent unauthorised access H04W12/08; Network selection; Access point selection
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Methods, systems, and devices for wireless communication are described. A user equipment (UE) may monitor a neighbor cell and report the result to a serving base station. Based on the report, the serving base station may identify an estimated discovery reference signal (DRS) transmission window of the neighbor cell. In some cases, the UE may estimate and report parameters of the neighbor DRS transmission window, and in other cases, the UE may make a measurement report and the base station may infer DRS transmission window parameters. The base station may then provide the UE with a DRS measurement timing configuration (DMTC) based on the estimated parameters of the neighbor cell so that the UE may monitor the neighbor cell and the serving cell in an efficient manner. For example, the UE may conserve battery life by refraining from monitoring DRS during periods when a DRS transmission is not likely.

Claims

1. A method of wireless communication comprising:

receiving a user equipment (UE) measurement report from a UE that includes information regarding a discovery reference signal (DRS) of a neighbor cell;

determining, based at least in part on the UE measurement report, one or more parameters associated with a DRS transmission window of the neighbor cell; and

transmitting a message that includes a DRS measurement timing configuration (DMTC) to the UE, wherein the DMTC is based at least in part on the one or more parameters associated with the DRS transmission window of the neighbor cell determined based at least in part on the UE measurement report.

2. The method of claim 1, wherein the DMTC comprises a configuration for a connected mode of the UE.

3. The method of claim 1, wherein the DMTC comprises a configuration for an idle mode of the UE.

4. The method of claim 1, wherein the one or more parameters associated with the DRS transmission window comprise a DRS transmission window offset parameter, a DRS transmission window periodicity parameter, or a DRS transmission window length parameter.

5. The method of claim 1, wherein the UE measurement report comprises:

signaling from the UE that indicates a UE estimate of the one or more parameters associated with the DRS transmission window of the neighbor cell, wherein the UE estimate is associated with a cell or a frequency, and wherein the one or more parameters are determined based at least in part on the UE estimate.

6. The method of claim 1, further comprising:

identifying a time stamp of the UE measurement report, wherein the one or more parameters associated with the DRS transmission window of the neighbor cell are determined based at least in part on the time stamp of the UE measurement report.

7. The method of claim 1, further comprising:

estimating a DRS transmission window periodicity, a DRS transmission window offset, or a DRS transmission window length for the neighbor cell; and

configuring the UE to perform a measurement of the neighbor cell based at least in part on the DRS transmission window periodicity, the DRS transmission window offset, or the DRS transmission window length, wherein the UE measurement report is based at least in part on the measurement.

8. The method of claim 7, wherein configuring the UE to perform the measurement comprises:

configuring the UE to perform the measurement for subframes that use DRS specific scrambling.

9. The method of claim 7, wherein the estimated DRS transmission window periodicity, the estimated DRS transmission window offset, or the DRS transmission window length is based at least in part on an interval comprising a maximum number of reference signal received power (RSRP) observations.

10. The method of claim 1, wherein a periodicity of the DMTC is an integer multiple or an integer divisor of a periodicity of a DRS transmission window, or wherein an on duration or an offset of the DMTC are configured to include at least a portion of the DRS transmission window.

11. The method of claim 1, further comprising:

storing the one or more parameters associated with the DRS transmission window of the neighbor cell; and

transmitting a subsequent message comprising a subsequent DMTC based at least in part on the one or more stored parameters.

12. The method of claim 1, wherein the DMTC comprises a plurality of parameters corresponding to a plurality of frequencies.

13. The method of claim 1, further comprising:

transmitting an indication of a subframe type in a field of an eSIB or a C-PDCCH message, wherein the subframe type comprises a multimedia broadcast single frequency network (MBSFN) type or a non-MBSFN type.

14. The method of claim 1, further comprising:

transmitting a DRS indication for a subsequent subframe.

15. The method of claim 1, further comprising:

transmitting of a control region restriction for a subsequent DRS.

16. The method of claim 1, further comprising:

transmitting an indication of a subframe type in UE-specific layer 1 signaling.

17. An apparatus for wireless communication comprising:

means for receiving a user equipment (UE) measurement report from a UE that includes information regarding a discovery reference signal (DRS) of a neighbor cell;

means for determining, based at least in part on the UE measurement report, one or more parameters associated with a DRS transmission window of the neighbor cell; and

means for transmitting a message that includes a DRS measurement timing configuration (DMTC) to the UE, wherein the DMTC is based at least in part on the one or more parameters associated with the DRS transmission window of the neighbor cell determined based at least in part on the UE measurement report.

18. An apparatus for wireless communication, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

receive a user equipment (UE) measurement report from a UE that includes information regarding a discovery reference signal (DRS) of a neighbor cell;

determine, based at least in part on the UE measurement report, one or more parameters associated with a DRS transmission window of the neighbor cell; and

transmit a message that includes a DRS measurement timing configuration (DMTC) to the UE, wherein the DMTC is based at least in part on the one or more parameters associated with the DRS transmission window of the neighbor cell determined based at least in part on the UE measurement report.

19. The apparatus of claim 18, wherein the DMTC comprises a configuration for a connected mode of the UE.

20. The apparatus of claim 18, wherein the DMTC comprises a configuration for an idle mode of the UE.

21. The apparatus of claim 18, wherein the one or more parameters associated with the DRS transmission window comprise a DRS transmission window offset parameter, a DRS transmission window periodicity parameter, or a DRS transmission window length parameter.

22. The apparatus of claim 18, wherein the UE measurement report comprises:

signaling from the UE that indicates a UE estimate of the one or more parameters associated with the DRS transmission window of the neighbor cell, wherein the UE estimate is associated with a cell or a frequency, and wherein the one or more parameters are determined based at least in part on the UE estimate.

23. The apparatus of claim 18, wherein the instructions are operable to cause the apparatus to:

identify a time stamp of the UE measurement report, wherein the one or more parameters associated with the DRS transmission window of the neighbor cell are determined based at least in part on the time stamp of the UE measurement report.

24. The apparatus of claim 18, wherein the instructions are operable to cause the apparatus to:

estimate a DRS transmission window periodicity, a DRS transmission window offset, or a DRS transmission window length for the neighbor cell; and

configure the UE to perform a measurement of the neighbor cell based at least in part on the DRS transmission window periodicity, the DRS transmission window offset, or the DRS transmission window length, wherein the UE measurement report is based at least in part on the measurement.

25. The apparatus of claim 24, wherein configuring the UE to perform the measurement comprises:

configuring the UE to perform the measurement for subframes that use DRS specific scrambling.

26. The apparatus of claim 24, wherein the estimated DRS transmission window periodicity, the estimated DRS transmission window offset, or the DRS transmission window length is based at least in part on an interval comprising a maximum number of reference signal received power (RSRP) observations.

27. The apparatus of claim 18, wherein a periodicity of the DMTC is an integer multiple or an integer divisor of a periodicity of a DRS transmission window, or wherein an on duration or an offset of the DMTC are configured to include at least a portion of the DRS transmission window.

28. The apparatus of claim 18, wherein the instructions are operable to cause the apparatus to:

store the one or more parameters associated with the DRS transmission window of the neighbor cell; and

transmit a subsequent message comprising a subsequent DMTC based at least in part on the one or more stored parameters.

29. The apparatus of claim 18, wherein the DMTC comprises a plurality of parameters corresponding to a plurality of frequencies.

30. The apparatus of claim 18, wherein the instructions are operable to cause the apparatus to:

transmit an indication of a subframe type in a field of an eSIB or a C-PDCCH message, wherein the subframe type comprises a multimedia broadcast single frequency network (MBSFN) type or a non-MBSFN type.

31. The apparatus of claim 18, wherein the instructions are operable to cause the apparatus to:

transmit a DRS indication for a subsequent subframe.

32. The apparatus of claim 18, wherein the instructions are operable to cause the apparatus to:

transmit of a control region restriction for a subsequent DRS.

33. The apparatus of claim 18, wherein the instructions are operable to cause the apparatus to:

transmit an indication of a subframe type in UE specific layer 1 signaling.

34. A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable to:

receive user equipment (UE) measurement report from a UE that includes information regarding a discovery reference signal (DRS) of a neighbor cell;

determine, based at least in part on the UE measurement report, one or more parameters associated with a DRS transmission window of the neighbor cell; and

transmit a message that includes a DRS measurement timing configuration (DMTC) to the UE, wherein the DMTC is based at least in part on the one or more parameters associated with the DRS transmission window of the neighbor cell determined based at least in part on the UE measurement report.

35. A method of wireless communication at a user equipment (UE), comprising:

sending user equipment (UE) measurement report from a UE to a base station that includes information regarding a discovery reference signal (DRS) of a neighbor cell;

receiving, from the base station, a message that includes a DRS measurement timing configuration (DMTC), wherein the DMTC is based at least in part on one or more parameters determined by the base station, based at least in part on the UE measurement report, and associated with a DRS transmission window of the neighbor cell; and

monitoring for a DRS according to the DMTC included in the message received from the base station.

36. The method of claim 35, wherein the DMTC comprises a configuration for a connected mode of the UE.

37. The method of claim 35, wherein the DMTC comprises a configuration for an idle mode of the UE.

38. The method of claim 35, wherein the one or more parameters associated with the DRS transmission window comprise a DRS transmission window offset parameter, a DRS transmission window periodicity parameter, or a DRS transmission window length parameter.

39. The method of claim 35, wherein the UE measurement report comprises:

signaling to the base station that indicates a UE estimate of the one or more parameters associated with the DRS transmission window of the neighbor cell, wherein the UE estimate is associated with a cell or a frequency, and wherein the one or more parameters are determined based at least in part on the UE estimate.

40. A user equipment (UE) for wireless communication comprising:

means for sending a UE measurement report from the UE to a base station that includes information regarding a discovery reference signal (DRS) of a neighbor cell;

means for receiving, from the base station, a message that includes a DRS measurement timing configuration (DMTC), wherein the DMTC is based at least in part on one or more parameters determined by the base station, based at least in part on the UE measurement report, and associated with a DRS transmission window of the neighbor cell; and

means for monitoring for a DRS according to the DMTC included in the message received from the base station.

41. A user equipment (UE) for wireless communication comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the UE to;

send a UE measurement report from the UE to a base station that includes information regarding a discovery reference signal (DRS) of a neighbor cell;

receive, from the base station, a message that includes a DRS measurement timing configuration (DMTC), wherein the DMTC is based at least in part on one or more parameters determined by the base station, based at least in part on the UE measurement report, and associated with a DRS transmission window of the neighbor cell; and

monitor for a DRS according to the DMTC included in the message received from the base station.

42. The UE of claim 41, wherein the one or more parameters associated with the DRS transmission window comprise a DRS transmission window offset parameter, a DRS transmission window periodicity parameter, or a DRS transmission window length parameter.

43. The UE of claim 41, wherein the instructions, when executed by the processor, further cause the apparatus to:

transmit signaling to the base station that indicates a UE estimate of the one or more parameters associated with the DRS transmission window of the neighbor cell, wherein the UE estimate is associated with a cell or a frequency, and wherein the one or more parameters are determined based at least in part on the UE estimate.

44. The UE of claim 41, wherein the instructions, when executed by the processor, further cause the apparatus to:

transmit a measurement report to the base station, wherein the one or more parameters associated with the DRS transmission window of the neighbor cell are determined based at least in part on the UE measurement report.

45. A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable to:

send a UE measurement report from a user equipment (UE) to a base station that includes information regarding a discovery reference signal (DRS) of a neighbor cell;

receive, from the base station, a message that includes a DRS measurement timing configuration (DMTC), wherein the DMTC is based at least in part on one or more parameters determined by the base station, based at least in part on the UE measurement report, and associated with a DRS transmission window of the neighbor cell; and

monitor for a DRS according to the DMTC included in the message received from the base station.