Distributed paging in a cellular telecommunication system
View Patent ↗In a cellular telecommunication system having multiple cells and respectively associated base stations, a user equipment (UE) is paged by sending a paging request to the base station that most recently communicated with the UE. This base station pages the UE and upon failing to receive a response forwards the paging request to its the base stations of neighboring cells Each of these base stations pages the UE and upon failing to receive a response similarly forwards the paging request to further base stations of neighboring cells. This process is repeated to repeatedly expand the paging area until the UE is located or until a forwarding limit has been reached.
1. A method of paging a mobile communication terminal in a Long Term Evolution (LTE) telecommunication network having multiple eNode Bs associated with respective cells of the LTE telecommunication network, the method comprising:
identifying a first eNode B, wherein the first eNode B is associated with a first cell of the LTE telecommunication network;
sending a first paging request to the first eNode B from a mobility management entity (MME) of the LTE telecommunication network using an S1 logical interface between the MME and the first eNode B;
receiving the first paging request at the first eNode B;
paging the mobile communication terminal from the first eNode B;
determining that the mobile communication terminal has not responded to the paging; and
in response to determining that the mobile communication terminal has not responded to the paging, (a) identifying a plurality of second eNode Bs that are associated respectively with cells of the LTE telecommunication network that geographically neighbor the first cell, and (b) forwarding the first paging request from the first eNode B to the second eNode Bs using X2 logical interfaces between the first eNode B and the second eNode Bs, respectively.
2. The method of claim 1 , wherein the forwarding comprises forwarding the first paging request to a group of the second eNode Bs that have been most highly utilized by the first eNode B.
3. The method of claim 1 , further comprising waiting for a wait time after determining that the mobile communication terminal has not responded to the paging before forwarding the first paging request.
4. The method of claim 1 , further comprising:
receiving a second paging request at the first eNode B;
determining that the second paging request is a duplicate of the first paging request; and
in response to determining that the second paging request is a duplicate of the first paging request, disregarding the second paging request.
5. The method of claim 1 , wherein identifying the first eNode B comprises determining which of the multiple eNode Bs most recently received a communication from the mobile communication terminal.
6. The method of claim 1 , wherein identifying the first eNode B comprises identifying an LTE tracking area within which the mobile communication terminal is located, the method further comprising sending the first paging request from the MME to multiple eNode Bs associated with the LTE tracking area.
7. The method of claim 1 , further comprising
receiving the first paging request by one of the second eNode Bs, wherein the one of the second eNode Bs is associated with a second cell;
paging the mobile communication terminal from the one of the second eNode Bs;
determining that the mobile communication terminal has not responded to the paging from the one of the second eNode Bs;
in response to determining that the mobile communication terminal has not responded to the paging from the one of the second eNode Bs, identifying a plurality of third eNode Bs that are associated respectively with cells of the LTE telecommunication network that neighbor the second cell; and
forwarding the first paging request from the one of the second eNode Bs to the third eNode Bs using X2 logical interfaces between the one of the second eNode Bs and the third eNode Bs, respectively.
8. The method of claim 1 , wherein the first paging request specifies a forwarding limit, the method further comprising:
receiving the first paging request by one of the second eNode Bs;
paging the mobile communication terminal from the one of the second eNode Bs;
determining that the mobile communication terminal has not responded to the paging from the one of the second eNode Bs;
determining that the forwarding limit has not been exceeded; and
in response to determining forwarding limit has not been exceeded, forwarding the first paging request from the one of the second eNode Bs to third eNode Bs using X2 communication interfaces between the one of the second eNode Bs and the third eNode Bs, respectively.
9. The method of claim 8 , wherein the forwarding limit comprises one or more of:
a time limit; or
a limit on a number of times that the first paging request is forwarded.
10. The method of claim 1 , wherein forwarding the first paging request comprises:
prioritizing multiple ones of the second eNode Bs;
forwarding the first paging request to the prioritized second eNode Bs at a first time;
forwarding the first paging request to second eNode Bs other than the prioritized second eNode Bs at a second time;
wherein the second time follows the first time by a prioritization delay.
11. The method of claim 1 , further comprising:
receiving the first paging request at a third eNode B, wherein the third eNode B is associated with a third cell;
paging the mobile communication terminal from the third eNode B;
determining that the mobile communication terminal has responded to the paging from the third eNode B; and
in response to determining that the mobile communication terminal has responded to the paging from the third eNode B, sending a cancellation request to one or more fourth eNode Bs that are associated respectively with cells of the LTE telecommunication network that geographically neighbor the third cell, wherein the cancellation request instructs the fourth eNode Bs to cancel forwarding of the first paging request.
12. A first base station for use in association with a first cell of a cellular telecommunication network, the first base station comprising:
one or more processors;
one or more non-transitory computer-readable media storing computer-executable instructions that, when executed on the one or more processors, cause the one or more processors to perform actions comprising:
receiving a paging request that specifies a mobile communication terminal;
paging the mobile communication terminal in response to receiving the paging request;
determining that the mobile communication terminal has not responded to the paging; and
in response to determining that the mobile communication terminal has not responded to the paging, (a) identifying a plurality of second base stations that are associated respectively with cells of the cellular telecommunication network that geographically neighbor the first cell, and (b) forwarding the paging request from the first base station to the second base stations;
the one or more non-transitory computer-readable media also storing data identifying the cells of the cellular telecommunication network that geographically neighbor the first cell.
13. The first base station of claim 12 , the actions further comprising:
receiving a cancellation request corresponding to the paging request, wherein the cancellation request specifies a cell traversal history;
examining the cell traversal history to determine an upstream base station from which the paging request was received; and
forwarding the cancellation request to the upstream base station.
14. The first base station of claim 12 , wherein the first base station comprises a Long Term Evolution (LTE) eNode B.
15. The first base station of claim 12 , wherein:
the cellular telecommunication network comprises a Long Term Evolution (LTE) network; and
forwarding the paging request from the first base station to the second base stations uses X2 logical interfaces of the LTE network.
16. The first base station of claim 12 , wherein the receiving comprises receiving the paging request from a management component of the cellular telecommunication network over a backhaul communication channel between the management component and the first base station.
17. The first base station of claim 12 , wherein the receiving comprises receiving the paging request from a third base station of the cellular telecommunication network.
18. The first base station of claim 12 , wherein forwarding the paging request from the first base station to the plurality of second base stations comprises communicating with each second base station using a Long Term Evolution (LTE) X2 logical interface between the first base station and the second base station.
19. The first base station of claim 12 , wherein the receiving comprises receiving the paging request from a third base station of the cellular telecommunication network using a Long Term Evolution (LTE) X2 logical interface between the first base station and the third base station.
20. The first base station of claim 12 , wherein:
the paging request specifies a neighbor limit parameter; and
identifying the plurality of second base stations comprises limiting a number of the identified plurality of second base stations based at least in part on the neighbor limit parameter.
21. The first base station of claim 12 , wherein forwarding the paging request comprises:
prioritizing multiple ones of the second base stations;
forwarding the paging request to the prioritized second base stations at a first time;
forwarding the paging request to second base stations other than the prioritized second base stations at a second time;
wherein the second time follows the first time by a prioritization delay.
22. A method performed by a first base station for use in association with a first cell of a cellular telecommunication network, the method comprising:
receiving a first paging request that specifies a first mobile communication terminal;
paging the first mobile communication terminal in response to receiving the paging request;
determining that a response from the first mobile communication terminal to the paging has not been received; and
in response to determining that a response from the first mobile communication terminal to the paging has not been received, (a) identifying a plurality of second base stations that are associated respectively with cells of the cellular telecommunication network that geographically neighbor the first cell, and (b) forwarding the first paging request from the first base station to the second base stations,
the first base station storing data identifying the cells of the cellular telecommunication network that geographically neighbor the first cell.
23. The method of claim 22 , wherein the receiving comprises receiving the first paging request from a management component of the cellular telecommunication network over a backhaul communication channel between the management component and the first base station.
24. The method of claim 22 , wherein the receiving comprises receiving the first paging request from a third base station of the cellular telecommunication network.
25. The method of claim 22 , further comprising:
receiving a second paging request from a third base station of the cellular telecommunication network, wherein the second paging request specifies a second mobile communications terminal;
paging the second mobile communication terminal;
receiving a response from the second mobile communication terminal; and
sending a paging cancellation request to the third base station.
26. The method of claim 22 , wherein forwarding the first paging request from the first base station to the plurality of second base stations comprises communicating with each second base station using a Long Term Evolution (LTE) X2 logical interface between the first base station and the second base station.
27. The method of claim 22 , wherein the receiving comprises receiving the first paging request from a third base station of the cellular telecommunication network using a Long Term Evolution (LTE) X2 logical interface between the first base station and the second base station between the first base station and the third base station.
28. The method of claim 22 , wherein forwarding the first paging request comprises:
prioritizing multiple ones of the second base stations;
forwarding the paging request to the prioritized second base stations at a first time;
forwarding the paging request to second base stations other than the prioritized second base stations at a second time;
wherein the second time follows the first time by a prioritization delay.