Handover signaling using an MBSFN channel in a cellular communication system

• US 10,004,022 B2
• Filed: 11/12/2012
• Issued: 06/19/2018
• Est. Priority Date: 11/15/2011
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Kalhan, Amit, Chang, Henry, Dunn, Douglas, Comstock, David
• Primary Examiner(s): Anwar, Mohammad
• Assistant Examiner(s): BROCKMAN, ANGEL T
• Application Number:
  US14/358,354
• Publication Number:
  US 20140314047A1
• Time in Patent Office: 2,045 Days
• CPC Class Codes: H04W 36/0011 for data sessions of end-to-end connection
• CPC Class Codes: H04W 36/0072 of resource information of target access point
• CPC Class Codes: H04W 36/0088 Scheduling hand-off measurements
• CPC Class Codes: H04W 36/38 by fixed network equipment

Abstract

A method of handover signaling in a cellular communication system is disclosed. Prior to a user equipment (UE) undergoing a cell-to-cell transition, a target node transmits handover-related signaling in one or more Multicast Broadcast Single Frequency Network (M8SFN) subframes in order to reduce handover delay. The cellular communication system includes a source node configured to transfer a handover (HO) request to the target node. The (HO) request corresponds to a (UE) presently being served by the source node. The target node is configured to transmit (HO) information to the (UE) over at least one MBSFN subframe in response to the (HO) request.

Claims

1. A cellular communication system, comprising:

a source node configured to transfer a handover (HO) request to a target node, the HO request corresponding to a user equipment (UE) presently being served by the source node; and

the target node configured to transmit HO information to the UE over a Multicast Broadcast Single Frequency Network (MBSFN) subframe in response to the HO request.

2. The cellular communication system of claim 1, wherein the target node is further configured to monitor at least one physical level transmission from the UE, and transmission of the HO information from the target node to the UE is based, in part, on the at least one physical level transmission.

3. The cellular communication system of claim 2, wherein the target node commences monitoring the at least one physical level transmission as a result of the target node receiving the HO request.

4. The cellular communication system of claim 2, wherein the target node is further configured to:

monitor a sounding reference signal (SRS) transmitted by the UE, and measure uplink (UL) timing of the UE.

5. The cellular communication system of claim 2, wherein the target node is further configured to unicast transmit the HO information in an unassigned MBSFN subframe.

6. The cellular communication system of claim 1, wherein the target node increases its transmit power during transmission of the MBSFN subframe containing the HO information.

7. The cellular communication system of claim 1, wherein the source node is configured to:

receive one or more measurement reports from the UE, and determine whether to transfer the HO request to the target node based on the measurement reports.

8. The cellular communication system of claim 1, wherein the source node does not transmit in the MBSFN subframe while the HO information is being transmitted by the target node.

9. A cellular system node, comprising:

means for monitoring at least one physical level transmission from a user equipment (UE) being served by another node; and

means for transmitting handover (HO) information to the UE over a Multicast Broadcast Single Frequency Network (MBSFN) subframe, based on the at least one physical level transmission.

10. The cellular system node of claim 9, further comprising:

means for receiving an HO request from the other node, the HO request corresponding to the UE;

means for commencing monitoring of the at least one physical level transmission from the UE as a result of receiving the HO request; and

means for transmitting HO information to the UE over the MBSFN subframe based on the at least one physical level transmission and in response to the HO request.

11. The cellular system node of claim 9, wherein the other node does not transmit in the MBSFN subframe while the HO information is being transmitted by the target node.

12. The cellular system node of claim 9, wherein the HO information is unicast transmitted in an unassigned MBSFN subframe.

13. A method of handover signaling in a cellular communication system, comprising:

transferring a handover (HO) request from a source node to a target node, the HO request corresponding to a user equipment (UE) presently being served by the source node; and

transmitting HO information from the target node to the UE over a Multicast Broadcast Single Frequency Network (MBSFN) subframe based on the HO request.

14. The method of claim 13, further comprising:

the target node monitoring at least one physical level transmission from the UE; and

transmitting HO information from the target node to the UE over a Multicast Broadcast Single Frequency Network (MBSFN) subframe based on the at least one physical level transmission and the HO request.

15. The method of claim 14, wherein monitoring the at least one physical level transmission commences as a result of the target node receiving the HO request.

16. The method of claim 14, wherein monitoring by the target node includes:

monitoring a sounding reference signal (SRS) transmitted by the UE; and

measuring uplink (UL) timing of the UE.

17. The method of claim 13, wherein the HO information is unicast transmitted in an unassigned MBSFN subsframe.

18. The method of claim 13, further comprising:

increasing transmit power of the target node during transmission of the MBSFN subframe containing the HO information.

19. The method of claim 13, further comprising:

receiving one or more measurement reports at the source node from the UE; and

the source node deciding to transfer the HO request to the target node based on the measurement reports.

20. The method of claim 13, wherein the source node does not transmit in the MBSFN subframe while the HO information is being transmitted by the target node.