Relay enhanced cellular telecommunication network
View Patent ↗Systems and techniques for avoiding inefficiencies resulting from failed handover attempts. A base station selects one or more mobility management entity (MME) pools for assignment to a relay node, with the selection being performed so as to minimize or eliminate handover attempts requiring that a target device support a particular MME pool when the MME pool is not supported by the MME. A base station selects, when communicating with a relay node, a subset of the MME pools that it supports and assigns the subset to the base station. UEs served by the relay node are assigned the MME pool or MME pools assigned to the relay node. The relay node is informed of the MME pools supported by one or more neighbor nodes and, when attempting a handover to a neighbor node, attempts an X2 handover only to neighbor nodes supporting an MME pool assigned to the relay node.
1. A method comprising:
configuring a base station to perform operations comprising:
sending a globally unique group identifier list to a device;
wherein sending the globally unique group identifier list to the device is performed upon one or more of initial association with the device or a configuration update for the device; and
wherein sending of the globally unique group identifier list comprises, if the device is a relay node associated with the base station, including in the globally unique group identifier list a subset of mobility management entity pool identifiers associated with the base station, wherein the mobility management entity pool identifiers included in the subset are chosen so as to exclude mobility management entity pool identifiers that are unsupported by one or more neighbor nodes of the device.
2. The method of claim 1 , wherein sending a globally unique group identifier list to a relay node further comprises assigning the one or more mobility management entity pools to all user equipments served by the relay node.
3. The method of claim 1 , wherein the globally unique group identifier list for a relay node is sent to the relay node upon initial attachment by the relay node to the apparatus.
4. The method of claim 1 , wherein the subset of mobility management entity pools selected for a relay node comprises a single mobility management entity pool.
5. The method of claim 1 , wherein the subset of mobility management entity pools selected for a relay node comprises all mobility management entity pools meeting the condition that the mobility management entity pool is supported by all neighboring cells of the relay node.
6. The method of claim 1 , wherein the operations further comprise, upon establishing a connection with a neighbor node, sending a configuration update to the relay node comprising a globally unique group identifier list identifying one or more mobility management entity pools supported by the neighbor node.
7. The method of claim 6 , wherein the operations further comprise responding to a change in the one or more mobility management entity pools supported by a neighbor node to send a configuration update to the relay node to report the change.
8. The method of claim 1 , wherein the operations further comprise causing the base station to assign one or more mobility management entity pools to the relay node based on information indicating which mobility management entity pools are supported by neighbors of the relay node.
9. The method of claim 7 , wherein the operations further comprise:
assigning a new mobility management entity pool to user equipments being served by the relay node; and
performing a mobility management entity relocation procedure for UEs not currently assigned to the new MME pool.
10. The method of claim 1 , wherein the operations further comprise:
receiving from the relay node information specifying one or more mobility management entity pools supported by neighbors of the relay node; and
assigning one or more mobility management entity pools to the relay node based on the information received from the relay node.
11. The method of claim 1 , wherein the operations further comprise:
configuring a relay node operating in a long term evolution wireless network to perform operations comprising:
identifying a mobility management entity pool serving a user equipment associated with the relay node
receiving information identifying one or more mobility management entity pools supported by a handover target;
comparing the one or more mobility management entity pools supported by the handover target to the MME pool serving the UE;
if the handover target supports the immobility management entity pool serving the user equipment, initiating an X2 handover to handover the user equipment to the target; and
if the handover target does not support the mobility management entity pool serving the user equipment, initiating an S1 handover to handover the user equipment to the target.
12. An apparatus comprising:
a least one processor;
memory storing computer program code;
wherein the memory and the computer program code are configured, with the at least one processor, to cause operations comprising:
controlling a base station to send a globally unique group identifier list to a device;
wherein sending the globally unique group identifier list to the device is performed upon one or more of initial association with the device or a configuration update for the device; and
wherein sending of the globally unique group identifier list comprises, if the device is a relay node associated with the base station, including in the globally unique group identifier list a subset of mobility management entity pool identifiers associated with the base station, wherein the MME pool identifiers included in the subset are chosen so as to exclude mobility management entity pool identifiers that are unsupported by one or more neighbor nodes of the device.
13. The apparatus of claim 12 , wherein sending a globally unique group identifier list to a relay node further comprises assigning the one or more mobility management entity pools to all user equipments served by the relay node.
14. The apparatus of claim 12 , wherein the subset of mobility management entity pools selected for a relay node comprises a single mobility management entity pool.
15. The apparatus of claim 12 , wherein the subset of mobility management entity pools selected for a relay node comprises all mobility management entity pools meeting the condition that the mobility management entity pool is supported by all neighboring cells of the relay node.
16. The apparatus of claim 12 , wherein the operations further comprise, upon establishing a connection with a neighbor node, sending a configuration update to the relay node comprising a globally unique group identifier list identifying one or more mobility management entity pools supported by the neighbor node.
17. The apparatus of claim 12 , wherein the operations further comprise:
causing the base station to assign one or more mobility management entity pools to the relay node based on information indicating which mobility management entity pools are supported by neighbors of the relay node;
assigning a new mobility management entity pool to user equipments being served by the relay node; and
performing a mobility management entity relocation procedure for UEs not currently assigned to the new MME pool.
18. The apparatus of claim 12 , wherein the operations further comprise:
receiving from the relay node information specifying one or more mobility management entity pools supported by neighbors of the relay node; and
assigning one or more mobility management entity pools to the relay node based on the information received from the relay node.
19. The apparatus of claim 12 , wherein the operations further comprise:
configuring a relay node operating in a long term evolution wireless network to perform operations comprising:
identifying a mobility management entity pool serving a user equipment associated with the relay node
receiving information identifying one or more mobility management entity pools supported by a handover target;
comparing the one or more mobility management entity pools supported by the handover target to the MME pool serving the UE;
if the handover target supports the mobility management entity pool serving the user equipment, initiating an X2 handover to handover the user equipment to the target; and
if the handover target does not support the mobility management entity pool serving the user equipment, initiating an S1 handover to handover the user equipment to the target.
20. A computer program product comprising a non-transitory computer-readable storage medium bearing computer program code embodied therein for use with a computer, the computer program code comprising:
code for configuring—a base station to perform operations, the configuring comprising:
sending a globally unique group identifier list to a device;
wherein sending the globally unique group identifier list to the device is performed upon one or more of initial association with the device or a configuration update for the device; and
wherein sending of the globally unique group identifier list comprises, if the device is a relay node associated with the base station, including in the globally unique group identifier list a subset of mobility management entity pool identifiers associated with the base station, wherein the mobility management entity pool identifiers included in the subset are chosen so as to exclude mobility management entity pool identifiers that are unsupported by one or more neighbor nodes of the device.