Evolved multimedia broadcast multicast service on enhanced component carriers

• US 9,883,485 B2
• Filed: 12/17/2015
• Issued: 01/30/2018
• Est. Priority Date: 01/08/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Zhang, Xiaoxia, Wang, Jun, Yoo, Taesang
• Primary Examiner(s): Ng, Christine
• Application Number:
  US14/973,300
• Publication Number:
  US 20160205664A1
• Time in Patent Office: 775 Days
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint
• CPC Class Codes: H04L 5/00 Arrangements affording multiple use of the transmission path
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/30 Resource management for broadcast services

Abstract

Methods, systems, and devices are described for evolved multimedia broadcast multicast service (eMBMS) utilizing enhanced component carriers (eCCs). A wireless system may send unicast data using resources allocated for multicast transmissions (e.g., eMBMS transmissions). The presence of unicast data in a transmission time interval (TTI) scheduled for multicast transmission may be indicated by a control region within the TTI. A UE may monitor the control region to identify the presence of unicast information. A TTI scheduled for multicast transmission may also include reference signals to aid in the demodulation of multicast or unicast data. In some cases, the reference signals may be front-loaded at the beginning or embedded within the TTI. The embedded reference signals may be configured based on the type of data carried by the TTI scheduled for multicast transmission, or by length of the cyclic prefix used by the TTI scheduled for multicast transmission.

Claims

1. A method of communication at a wireless device, comprising:

determining that a set of resources is scheduled for an evolved multimedia broadcast multicast service (eMBMS);

determining that a first symbol period of the set of resources is associated with a cell-specific reference signal (CRS) preamble and a second symbol period of the set of resources is a unicast control symbol period;

identifying a control message in the unicast control symbol period indicating a unicast data transmission utilizing the set of resources;

performing a CRS on/off detection for a subframe associated with the set of resources;

receiving at least one CRS during the subframe based at least in part on the CRS on/off detection; and

combining the at least one CRS with accumulated CRS data based at least in part on the CRS on/off detection.

2. The method of claim 1, further comprising:

receiving at least one demodulation reference signal (DMRS) during the subframe associated with the set of resources.

3. The method of claim 2, wherein the at least one DMRS utilizes at least one resource element associated with a CRS pattern.

4. The method of claim 3, wherein the at least one DMRS utilizes a low-density resource pattern for a set of non-CRS resource elements.

5. The method of claim 1, further comprising:

receiving the control message during the unicast control symbol period; and

receiving the unicast data transmission during the subframe associated with the set of resources based at least in part on the control message.

6. The method of claim 1, further comprising:

transmitting the control message during the unicast control symbol period; and

transmitting the unicast data transmission during the subframe associated with the set of resources.

7. The method of claim 1, further comprising:

determining that a second set of resources is scheduled for a second eMBMS.

8. The method of claim 7, further comprising:

determining that the set of resources and the second set of resources are multiplexed according to a frequency division multiplexing (FDM) configuration.

9. The method of claim 7, further comprising:

determining that the set of resources and the second set of resources are multiplexed according to a time division multiplexing (TDM) configuration.

10. The method of claim 1, further comprising:

receiving an eMBMS preemption indication; and

determining that the set of resources scheduled for the eMBMS contains unicast data based at least in part on the eMBMS preemption indication.

11. The method of claim 1, wherein the set of resources are based at least in part on a reduced symbol period, wherein the reduced symbol period corresponds to an enhanced component carrier (eCC) configuration.

12. The method of claim 11, wherein the reduced symbol period is equal to a clear channel assessment (CCA) length.

13. The method of claim 11, wherein the reduced symbol period is based at least in part on an extended cyclic prefix (CP) length.

14. The method of claim 13, wherein the reduced symbol period based at least in part on the extended CP length corresponds to a bandwidth range associated with the eMBMS and a second reduced symbol period based at least in part on a non-extended CP length corresponds to a bandwidth range associated with unicast transmission.

15. The method of claim 1, wherein the control message uses a physical uplink format indicator channel (PUFICH) format or resource assignment.

16. The method of claim 1, wherein determining that the set of resources is scheduled for the eMBMS comprises:

receiving a system information block (SIB) indicating the eMBMS and receiving a multicast control channel (MCCH) based at least in part on the SIB.

17. An apparatus for communication at a wireless device, comprising:

means for determining that a set of resources is scheduled for an evolved multimedia broadcast multicast service (eMBMS);

means for determining that a first symbol period of the set of resources is associated with a cell-specific reference signals (CRS) preamble and a second symbol period of the set of resources is a unicast control symbol period;

means for identifying a control message in the unicast control symbol period indicating a unicast data transmission utilizing the set of resources;

means for performing a CRS on/off detection for a subframe associated with the set of resources;

means for receiving at least one CRS during the subframe based at least in part on the CRS on/off detection; and

means for combining the at least one CRS with accumulated CRS data based at least in part on the CRS on/off detection.

18. An apparatus for communication at a wireless device, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory;

wherein the instructions are executable by the processor to cause the apparatus to;

determine that a set of resources is scheduled for an evolved multimedia broadcast multicast service (eMBMS);

determine that a first symbol period of the set of resources is associated with a cell-specific reference signals (CRS) preamble and a second symbol period of the set of resources is a unicast control symbol period;

identify a control message in the unicast control symbol period indicating a unicast data transmission utilizing the set of resources;

perform a CRS on/off detection for a subframe associated with the set of resources;

receive at least one CRS during the subframe based at least in part on the CRS on/off detection; and

combine the at least one CRS with accumulated CRS data based at least in part on the CRS on/off detection.

19. The apparatus of claim 18, wherein the instructions are executable by the processor to cause the apparatus to:

receive at least one demodulation reference signal (DMRS) during the subframe associated with the set of resources.

20. The apparatus of claim 19, wherein the at least one DMRS utilizes at least one resource element associated with a CRS pattern and a low-density resource pattern for a set of non-CRS resource elements.

21. The apparatus of claim 18, wherein the instructions are executable by the processor to cause the apparatus to:

receive the control message during the unicast control symbol period; and

receive the unicast data transmission during the subframe associated with the set of resources based at least in part on the control message.

22. The apparatus of claim 18, wherein the instructions are executable by the processor to cause the apparatus to:

transmit the control message during the unicast control symbol period; and

transmit the unicast data transmission during the subframe associated with the set of resources.

23. The apparatus of claim 18, wherein the instructions are executable by the processor to:

determine that a second set of resources is scheduled for a second eMBMS.

24. The apparatus of claim 23, wherein the instructions are executable by the processor to cause the apparatus to:

determine that the set of resources and the second set of resources are multiplexed according to a frequency division multiplexing (FDM) configuration.

25. The apparatus of claim 23, wherein the instructions are executable by the processor to cause the apparatus to:

determine that the set of resources and the second set of resources are multiplexed according to a time division multiplexing (TDM) configuration.

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

determine that a set of resources is scheduled for an evolved multimedia broadcast multicast service (eMBMS);

determine that a first symbol period of the set of resources is associated with a cell-specific reference signals (CRS) preamble and a second symbol period of the set of resources is a unicast control symbol period;

identify a control message in the unicast control symbol period indicating a unicast data transmission utilizing the set of resources;

perform a CRS on/off detection for a subframe associated with the set of resources;

receive at least one CRS during the subframe based at least in part on the CRS on/off detection; and

combine the at least one CRS with accumulated CRS data based at least in part on the CRS on/off detection.