METHODS AND APPARATUS FOR QUICKLY EXPLOITING A NEW LINK DURING HAND-OFF IN A WIRELESS NETWORK

• US 20090040967A1
• Filed: 10/22/2008
• Published: 02/12/2009
• Est. Priority Date: 10/10/2001
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: O'Neill, Alan
• Granted Patent: US 8,411,639 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04W 36/0005 Control or signalling for completing the hand-off
• CPC Class Codes: H04W 36/0016 Hand-off preparation specially adapted for end-to-end data sessions
• CPC Class Codes: H04W 36/00692 using simultaneous multiple data streams, e.g. cooperative multipoint [CoMP], carrier aggregation [CA] or multiple input multiple output [MIMO] allocation of physical resources in CoMP or in CA H04L5/0035
• CPC Class Codes: H04W 36/02 Buffering or recovering information during reselection ; Modification of the traffic flow during hand-off
• CPC Class Codes: H04W 36/16 Performing reselection for specific purposes
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling

Abstract

A way to deliver traffic to a mobile node that is undergoing a hand-off between two Access Routers (AR) is described. The method of the present invention operates to perform some or all of the following. Decrease, e.g., minimize, delays between the time the old link breaks and the first packet is sent from the new link. Reduce and/or eliminate packet bursts from old to new AR when an old (existing) link breaks. Ensure that packets are neither lost nor duplicated during hand-off. Maintain QoS control of delivery order to the MN. Make good or best use of multiple links during Make before break hand-off. Support both uplink and downlink traffic.

Claims

1. A method of operating a mobile node comprising:

receiving a frame communicated over one of a first downlink with a first access router and a second downlink with a second access router prior to said frame having been successfully communicated over another one of said first and second downlinks, said first and second downlinks being unsynchronized downlinks with respect to frame transmissions; and

communicating acknowledgment information, to both said first access router and said second access routers, indicating the successful reception of said frame.

2. The method of claim 1 further comprising:

sending an acknowledgment over an uplink to said first access router and sending an acknowledgment over an uplink to said second access router.

3. The method of claim 1, wherein communicating acknowledgment information includes:

sending an acknowledgment to prevent the first access router from transmitting the content of said frame over said first downlink.

4. The method of claim 1, wherein said method is performed as part of a handoff from an old access router to a new access router, said first access router being said old access router, said second access router being said new access router.

5. The method of claim 4, wherein said frame is a mac layer frame communicating a portion of a packet.

6. The method of claim 1,

wherein said one said downlinks is said second downlink;

wherein an attempt to receive said frame over said first downlink resulted in an error; and

wherein communicating acknowledgement information includes transmitting an acknowledgement to said first access router indicating successful receipt of said frame which was not successfully received from said first access router.

7. The method of claim 6, further comprising, prior to transmitting said acknowledgement to said first access router, successfully receiving the content of said frame from the second downlink.

8. The method of claim 1, wherein said method is performed as part of a handoff from said first access router to said second access router.

9. A mobile node comprising:

means for receiving a frame communicated over one of a first downlink with a first access router and a second downlink with a second access router prior to the frame having been successfully communicated over another one of said first and second downlinks, said first and second downlinks being unsynchronized downlinks with respect to frame transmissions; and

means for communicating acknowledgment information, to both said first access router and said second access routers, indicating the successful reception of said frame.

10. The mobile node of claim 9, wherein said means for communicating acknowledgment information includes:

means for sending an acknowledgment over an uplink to said first access router and sending an acknowledgment over an uplink to said second access router.

11. The mobile node of claim 9, wherein said means for communicating acknowledgment information includes:

means for sending an acknowledgment to prevent said first access router from transmitting the content of said frame over said first downlink.

12. The mobile node of claim 9, wherein said first access router is an old access router and said second access router is a new access router to which said mobile node is being handed off from the old access router.

13. The mobile node of claim 12, wherein said frame is a mac layer frame communicating a portion of a packet.

14. The mobile node of claim 9,

wherein said one of said downlinks is said second downlink;

wherein an attempt to receive said frame over said first downlink resulted in an error; and

wherein said means for communicating acknowledgement information includes means for transmitting an acknowledgement to said first access router indicating successful receipt of said frame which was not successfully received from said first access router.