Methods to support continuous MBMS reception without network assistance

• US 20110305184A1
• Filed: 06/14/2011
• Published: 12/15/2011
• Est. Priority Date: 06/15/2010
• Status: Active Grant

• Current Assignee: HFI Innovation, Inc. (MediaTek, Inc.)
• Original Assignee: MediaTek, Inc.
• Inventors: Hsu, Chia-Chun
• Granted Patent: US 9,185,682 B2
• Time in Patent Office: Days
• US Class Current: 370/312
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04W 36/0007 for multicast or broadcast services, e.g. MBMS multicast or broadcast application services H04W4/06; resource management for broadcast services H04W72/30; connection management for selective distribution or broadcast H04W76/40
• CPC Class Codes: H04W 36/00835 Determination of neighbour cell lists
• CPC Class Codes: H04W 36/08 Reselecting an access point
• 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 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 76/40 for selective distribution or broadcast
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

In an LTE/LTE-A system, a UE subscribes to an MBMS service in a source cell. In one embodiment, the UE with ongoing MBMS service handovers to a target cell. The UE obtains MBMS information of the target cell before or after the handover. The UE then determines MBMS service continuity in the target cell based on the obtained MBMS information. In another embodiment, the UE with ongoing MBMS service reselects a new cell. The UE makes cell reselection decision based on obtained MBMS information of its neighbor cells. If the subscribed MBMS service is discontinued after handover or cell reselection, the UE releases MBMS bearer and informs a NAS entity. If the subscribed MBMS service is available after handover or cell reselection, the UE keeps MBMS bearer during handover or cell reselection. By acquiring MBMS information, the UE is able to maintain continuous MBMS reception after handover or cell reselection.

Claims

1. A method comprising:

receiving a subscribed multimedia broadcast multicast service (MBMS) service by a user equipment (UE) in a source cell;

performing handover to a target cell;

obtaining MBMS information of the target cell, wherein the MBMS information comprises an MBMS single frequency network (MBSFN) area ID of the target cell; and

determining MBMS service continuity in the target cell, wherein the UE releases MBMS bearer and informs a non-access stratum (NAS) entity if the subscribed MBMS service is discontinued after handover, and wherein the UE keeps MBMS bearer during handover if the subscribed MBMS service is available after handover.

2. The method of claim 1, wherein the source cell and the target cell belong to the same MBSFN area, and wherein the UE reuses MBMS information of the source cell after handover.

3. The method of claim 1, wherein the serving cell and the target cell belong to different MBSFN areas, and wherein the UE obtains an MBMS service list from a multicast control channel (MCCH) of the target cell.

4. The method of claim 1, further comprising:

providing a prompt for whether to continue the subscribed MBMS service in the target cell.

5. The method of claim 1, wherein the UE subscribes multiple MBMS services from one or more MBSFN areas, and wherein the UE determines whether the subscribed MBMS services are available by checking each multicast control channel (MCCH) of each MBSFN area supported by the target cell.

6. The method of claim 1, wherein the subscribed MBMS service is provided by multiple MBSFN areas supported by the target cell, and wherein a preferred MBSFN area is selected based on user preference or a predetermined priority.

7. The method of claim 1, wherein the UE receives a handover command indicating a first number of carrier frequencies supporting MBMS by a target eNB, wherein the UE is capable of receiving MBMS over a second number of carrier frequencies, and wherein a preferred MBSFN area is selected based on user preference or a predetermined priority.

8. A user equipment (UE), comprising:

a radio frequency (RF) module that receives a subscribed multimedia broadcast multicast service (MBMS) service from a multimedia broadcast service center (MBSC);

a handover (HO) module that performs handover from a source cell to a target cell; and

an MBMS module that obtains MBMS information of the target cell, wherein the MBMS information comprises an MBMS single frequency network (MBSFN) area ID, wherein the UE releases MBMS bearer and informs a non-access stratum (NAS) entity if the subscribed MBMS service is discontinued after handover, and wherein the UE keeps MBMS bearer during handover if the subscribed MBMS service is available after handover.

9. The UE of claim 8, wherein the source cell and the target cell belong to the same MBSFN area, and wherein the UE reuses MBMS information of the source cell after handover.

10. The UE of claim 8, wherein the source cell and the target cell belong to different MBSFN areas, and wherein the UE obtains an MNMS service list from a multicast control channel (MCCH) of the target cell.

11. The UE of claim 8, further comprising:

a user interface module that provides a prompt for whether to continue the subscribed MBMS service in the target cell.

12. The UE of claim 8, wherein the UE subscribes multiple MBMS services from one or more MBSFN areas, and wherein the UE determines whether the subscribed MBMS services are available by checking each multicast control channel (MCCH) of each MBSFN area supported by the target cell.

13. The UE of claim 8, wherein the subscribed MBMS service is provided by multiple MBSFN areas supported by the target cell, and wherein a preferred MBSFN area is selected based on user preference or a predetermined priority.

14. A method comprising:

receiving a subscribed multimedia broadcast multicast service (MBMS) service by a user equipment (UE) in a first cell;

obtaining MBMS information of neighbor cells, wherein the MBMS information comprises an MBMS single frequency network (MBSFN) area ID, MBMS configuration information, and an MBMS service list; and

determining a second cell from the neighbor cells for cell reselection based on the obtained MBMS information, wherein the UE releases MBMS bearer and informs a non-access stratum (NAS) entity if the UE discontinues the subscribed MBMS service, and wherein the UE keeps MBMS bearer during cell reselection if the subscribed MBMS service is available after cell reselection.

15. The method of claim 14, wherein the second cell is determined based on user preference or a predetermined priority.

16. The method of claim 14, further comprising:

providing a prompt for whether to reselect cell and which cell to be determined as the second cell for cell reselection.

17. The method of claim 14, further comprising:

providing a prompt for whether to continue the subscribed MBMS service in the second cell.

18. The method of claim 14, wherein the UE subscribes multiple MBMS services from one or more MBSFN areas, and wherein the UE determines whether the subscribed MBMS services are available by checking each multicast control channel (MCCH) of each MBSFN area supported by the neighbor cells.

19. The method of claim 14, wherein the subscribed MBMS service is provided by multiple MBSFN areas supported by the second cell, and wherein a preferred MBSFN area is selected based on user preference or a predetermined priority.

20. A user equipment (UE), comprising:

a radio frequency (RF) module that receives a subscribed multimedia broadcast multicast service (MBMS) service in a first cell from a multimedia broadcast service center (MBSC); and

an MBMS module that obtains MBMS information of neighbor cells and thereby determining a second cell from the neighbor cells for cell reselection, wherein the MBMS information comprises an MBMS single frequency network (MBSFN) area ID, MBMS configuration information, and an MBMS service list, wherein the UE releases MBMS bearer and informs a non-access stratum (NAS) entity if the UE discontinues the subscribed MBMS service, and wherein the UE keeps MBMS bearer during cell reselection if the subscribed MBMS service is available after cell reselection.

21. The UE of claim 20, wherein the second cell is determined based on user preference or a predetermined priority.

22. The UE of claim 20, further comprising:

a user interface module that provides a prompt for which cell to be determined as the second cell for cell reselection.

23. The UE of claim 20, further comprising:

a user interface module that provides a prompt for whether to continue the subscribed MBMS service in the second cell.

24. The UE of claim 20, wherein the UE subscribes multiple MBMS services from one or more MBSFN areas, and wherein the UE determines whether the subscribed MBMS services are available by checking each multicast control channel (MCCH) of each MBSFN area supported by the neighbor cells.

25. The UE of claim 20, wherein the subscribed MBMS service is provided by multiple MBSFN areas supported by the second cell, and wherein a preferred MBSFN area is selected based on user preference or a predetermined priority.