L2 tunneling based low latency single radio handoffs

Abstract

An example of this invention provides low latency handovers between Mobile WiMAX and 2G/3G/LTE networks with only a single radio transmitting at any given point in time, by establishing L2 tunnel between 3GPP MME and WiMAX ASN for control plane signaling to perform pre-registration, pre-authentication and context transfer to the target network, while UE maintains its connection to the source network, and by setting up bearer path for packet forwarding between Servicing Gateway and WiMAX ASN. An example of this invention uses a virtual eNB to facilitate low latency L2 handoffs to legacy 2G/3G networks with minimum impact to SGSN and MME.

1 - 30 . (canceled) 
     
     
         31 . A user equipment (UE) to execute an inter-network handover, the UE being configured to:
 communicate with a source radio network;   receive a message from the source radio network to initiate a handover procedure to a target radio network;   exchange messages with the target radio network via the source radio network through a tunnel established between the source radio network and the target radio network; and   switch from the source radio network to the target radio network to execute the handover, wherein handover signaling is tunneled between the UE and the target network via the tunnel.   
     
     
         32 . A user equipment as claimed in  claim 31 , wherein the tunnel comprises an S101 interface between the source radio network and the target radio network. 
     
     
         33 . A user equipment as claimed in  claim 31 , wherein the UE is further configured to pre-register with a target radio network prior to executing the handover. 
     
     
         34 . A user equipment as claimed in  claim 31 , wherein the messages are exchanged inside radio resource control (RRC) messages. 
     
     
         35 . A user equipment as claimed in  claim 31 , wherein the source radio network comprises a Third Generation Partnership Project (3GPP) network and the target radio comprises a non-3GPP network. 
     
     
         36 . A user equipment as claimed in  claim 31 , wherein the target radio network comprises a Code Division Multiple Access (CDMA) network. 
     
     
         37 . A user equipment as claimed in  claim 31 , wherein the target network comprises a high data rate Packet (HDRP) network. 
     
     
         38 . A method to execute an inter-network handover, the method comprising:
 communicating with a source radio network;   receiving a message from the source radio network to initiate a handover procedure to the target radio network;   exchanging messages with the target radio network via the source radio network through a tunnel established between the source radio network and the target radio network; and   switching from the source radio network to the target radio network to execute the handover, wherein handover signaling is tunneled between the UE and the target network via the tunnel.   
     
     
         39 . A method equipment as claimed in  claim 38 , wherein the tunnel comprises an S101 interface between the source radio network and the target radio network. 
     
     
         40 . A method equipment as claimed in  claim 38 , wherein the UE is further configured to pre-register with a target radio network prior to executing the handover. 
     
     
         41 . A method equipment as claimed in  claim 38 , wherein the messages are exchanged inside radio resource control (RRC) messages. 
     
     
         42 . A method equipment as claimed in  claim 38 , wherein the source radio network comprises a Third Generation Partnership Project (3GPP) network and the target radio comprises a non-3GPP network. 
     
     
         43 . A user equipment as claimed in  claim 38 , wherein the target radio network comprises a Code Division Multiple Access (CDMA) network. 
     
     
         44 . A user equipment as claimed in  claim 38 , wherein the target network comprises a high data rate Packet (HDRP) network. 
     
     
         45 . An enhanced Node B (eNB) to facilitate an inter-network handover for a user equipment (UE), the eNB being configured to:
 couple the UE to a source radio network;   send a message to the UE to initiate a handover procedure to a target radio network;   transfer messages between the UE and the target radio network via the source radio network through a tunnel established between the source radio network and the target radio network; and   tunnel handover signals between the UE and the target network via the tunnel to facilitate the handover of the UE from the source network to the target network.   
     
     
         46 . An enhanced Node B as claimed in  claim 45 , wherein the tunnel comprises an S101 interface between the source radio network and the target radio network. 
     
     
         47 . An enhanced Node B as claimed in  claim 45 , wherein the UE is further configured to pre-register with a target radio network prior to executing the handover. 
     
     
         48 . An enhanced Node B as claimed in  claim 45 , wherein the messages are exchanged inside radio resource control (RRC) messages. 
     
     
         49 . An enhanced Node B as claimed in  claim 45 , wherein the source radio network comprises a Third Generation Partnership Project (3GPP) network and the target radio comprises a non-3GPP network. 
     
     
         50 . An enhanced Node B as claimed in  claim 45 , wherein the target radio network comprises a Code Division Multiple Access (CDMA) network. 
     
     
         51 . An enhanced Node B as claimed in  claim 45 , wherein the target network comprises a high data rate Packet (HDRP) network. 
     
     
         52 . A method to execute an inter-network handover, the method comprising:
 communicating with a source radio network;   receiving a message from the source radio network to initiate a handover procedure to the target radio network;   exchanging messages with the target radio network via the source radio network through a tunnel established between the source radio network and the target radio network; and   switching from the source radio network to the target radio network to execute the handover, wherein handover signaling is tunneled between the UE and the target network via the tunnel.   
     
     
         53 . A method as claimed in  claim 52 , wherein the tunnel comprises an S101 interface between the source radio network and the target radio network. 
     
     
         54 . A method as claimed in  claim 52 , wherein the UE is further configured to pre-register with a target radio network prior to executing the handover. 
     
     
         55 . A method as claimed in  claim 52 , wherein the messages are exchanged inside radio resource control (RRC) messages. 
     
     
         56 . A method as claimed in  claim 52 , wherein the source radio network comprises a Third Generation Partnership Project (3GPP) network and the target radio comprises a non-3GPP network. 
     
     
         57 . A method as claimed in  claim 52 , wherein the target radio network comprises a Code Division Multiple Access (CDMA) network. 
     
     
         58 . A method as claimed in  claim 52 , wherein the target network comprises a high data rate Packet (HDRP) network.