Radio access network node and method—time coordinated cells for extended discontinuous receive (eDRX)

1. A radio access network (RAN) node configured to interact with a core network (CN) node to time coordinate cells and maintain a reliability of paging a wireless device, the RAN node comprising:

a processor; and,

a memory that stores processor-executable instructions, wherein the processor interfaces with the memory to execute the processor-executable instructions, whereby the RAN node is operable to:

receive a paging request from the CN node, wherein the paging request includes information associated with the wireless device;

calculate, using at least the information associated with the wireless device, a time remaining until a next paging opportunity for the wireless device within the cells comprising a paging area of the wireless device; and,

transmit a paging response to the CN node, wherein the paging response includes the time remaining until a next paging opportunity for the wireless device,

wherein the information comprises the following:

an International Mobile Subscriber Identity (IMSI) of the wireless device;

an extended Discontinuous Receive (eDRX) cycle length of the wireless device; and

a coverage class of the wireless device.

2. The RAN node of claim 1 , wherein the RAN node is further operable to

in response to receiving the paging request, transmitting a paging message to the wireless device; and,

receiving a paging response from the wireless device.

3. The RAN node of claim 1 , wherein:

receiving the paging request from the CN node includes receiving a dummy paging request from the CN node, wherein the dummy paging request includes the information associated with the wireless device;

calculating the time remaining until the next paging opportunity for the wireless device includes, upon receiving the dummy paging request, calculating the time remaining until the next paging opportunity for the wireless device using at least the information associated with the wireless device without transmitting a paging message over a radio interface to the wireless device; and,

transmitting the paging response to the CN node includes transmitting a dummy paging response to the CN node, wherein the dummy paging response includes the time remaining until a next paging opportunity for the wireless device.

4. The RAN node of claim 3 , wherein:

the CN node is a Serving General Packet Radio Service (GPRS) Support Node (SGSN); and,

the RAN node is a Base Station Subsystem (BSS).

5. The RAN node of claim 1 , wherein the time remaining until the next paging opportunity for the wireless device that is included in the paging response transmitted to the CN node is for using with an extended Discontinuous Receive (eDRX) cycle length associated with the wireless device for the CN node to maintain an eDRX cycle timer associated with the wireless device.

6. The RAN node of claim 5 , wherein the eDRX cycle timer is set by the CN node to expire a predetermined time before the next paging opportunity for the wireless device.

7. A method in a radio access network (RAN) node for interacting with a core network (CN) node to time coordinate cells and maintain a reliability of paging a wireless device, the method comprising:

receiving a paging request from the CN node, wherein the paging request includes information associated with the wireless device;

calculating, using at least the information associated with the wireless device, a time remaining until a next paging opportunity for the wireless device within the cells comprising a paging area of the wireless device; and,

transmitting a paging response to the CN node, wherein the paging response includes the time remaining until a next paging opportunity for the wireless device,

wherein the information comprises the following:

an International Mobile Subscriber Identity (IMSI) of the wireless device;

an extended Discontinuous Receive (eDRX) cycle length of the wireless device; and

a coverage class of the wireless device.

8. The method of claim 7 , further comprising:

in response to receiving the paging request, transmitting a paging message to the wireless device; and,

receiving a paging response from the wireless device.

9. The method of claim 7 , wherein:

receiving the paging request from the CN node includes receiving a dummy paging request from the CN node, wherein the dummy paging request includes the information associated with the wireless device;

calculating the time remaining until the next paging opportunity for the wireless device includes, upon receiving the dummy paging request, calculating the time remaining until the next paging opportunity for the wireless device using at least the information associated with the wireless device without transmitting a paging message over a radio interface to the wireless device; and,

transmitting the paging response to the CN node includes transmitting a dummy paging response to the CN node, wherein the dummy paging response includes the time remaining until a next paging opportunity for the wireless device.

10. The method of claim 9 , wherein:

the CN node is a Serving General Packet Radio Service (GPRS) Support Node (SGSN); and,

the RAN node is a Base Station Subsystem (BSS).

11. The method of claim 7 , wherein the time remaining until the next paging opportunity for the wireless device that is included in the paging response transmitted to the CN node is for using with an extended Discontinuous Receive (eDRX) cycle length associated with the wireless device for the CN node to maintain an eDRX cycle timer associated with the wireless device.

12. The method of claim 11 , wherein the eDRX cycle timer is set by the CN node to expire a predetermined time before the next paging opportunity for the wireless device.