Radio Access Technology Selection

• US 20130136115A1
• Filed: 12/02/2011
• Published: 05/30/2013
• Est. Priority Date: 11/29/2011
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Renesas Mobile Corporation (Renesas Electronics Corporation)
• Inventors: MOISANEN, Matti, Pelkonen, Petri
• Granted Patent: US 8,761,138 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 36/0022 for transferring data sessions between adjacent core network technologies
• CPC Class Codes: H04W 36/00224 between packet switched [PS] and circuit switched [CS] network technologies, e.g. circuit switched fallback [CSFB]
• CPC Class Codes: H04W 36/0079 in case of hand-off failure or rejection
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 76/18 Management of setup rejection or failure

Abstract

There is provided a method, including detecting, by a user terminal connected to a public land mobile net-work, PLMN, via a first radio access technology and having requested a circuit switched fallback service procedure, that a network controlled radio access technology change related to the circuit switched fallback service procedure is not performed; and selecting a second radio access technology to be applied on the basis of stored information, wherein the second radio access technology to be applied is capable to provide circuit switched services and the stored information associates at least one PLMN with at least one radio access technology.

Claims

1. A method, comprising:

detecting, by a user terminal connected to a public land mobile network, PLMN, via a first radio access technology and having requested a circuit switched fallback service procedure, that a network controlled radio access technology change related to the circuit switched fallback service procedure is not performed; and

selecting a second radio access technology to be applied on the basis of stored information, wherein the second radio access technology to be applied is capable to provide circuit switched services and the stored information associates at least one PLMN with at least one radio access technology.

2. The method of claim 1, wherein the selected second radio access technology provides coverage for the current PLMN.

3. The method of claim 1, wherein the stored information comprises at least one PLMN selector list, wherein the at least one PLMN selector list is predefined by at least one PLMN and comprises at least one radio access technology candidate for the at least one PLMN.

4. The method of claim 3, further comprising:

selecting the second radio access technology which has the highest priority for the current PLMN, wherein the at least one PLMN selector list comprises prioritized at least one radio access technology candidate for the at least one PLMN.

5. The method of claim 4, further comprising:

verifying that the selected second radio access technology provides coverage for the current PLMN by applying coverage data, wherein the coverage data indicates which at least one radio access technology in the current geographical area provides coverage for the current PLMN.

6. The method of claim 3, further comprising:

selecting the second radio access technology from the at least one PLMN selector list having at least one non-prioritized radio access technology candidate for the at least one PLMN; and

selecting the second non-prioritized radio access technology which provides coverage for the current PLMN on the basis of coverage data, wherein the coverage data indicates which at least one radio access technology in the current geographical area provides coverage for the current PLMN.

7. The method of claim 3, wherein the at least one PLMN selector list is stored in a subscriber identity module coupled to the user terminal.

8. The method of claim 1, further comprising:

selecting the second radio access technology on the basis of coverage data, wherein the stored information comprises the coverage data indicating which at least one radio access technology is associated with which at least one PLMN in which geographical areas.

9. The method of claim 8, further comprising:

recording the coverage data by observing which at least one radio access technology has provided coverage for which of the at least one PLMN along at least part of the trajectory of the user terminal.

20. A computer program product embodied on a distribution medium readable by a computer and comprising program instructions which, when loaded into an apparatus, execute the method according to claim 1.

10. An apparatus, comprising:

at least one processor and at least one memory including a computer program code, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to;

detect that a network controlled radio access technology change related to a circuit switched fallback service procedure is not performed for a user terminal connected to a public land mobile network, PLMN, via a first radio access technology and having requested the circuit switched fallback service procedure; and

select a second radio access technology to be applied on the basis of stored information, wherein the second radio access technology to be applied is capable to provide circuit switched services and the stored information associates at least one PLMN with at least one radio access technology.

11. The apparatus of claim 10, wherein the selected second radio access technology provides coverage for the current PLMN.

12. The apparatus of claim 10, wherein the stored information comprises at least one PLMN selector list, wherein the at least one PLMN selector list is predefined by at least one PLMN and comprises at least one radio access technology candidate for the at least one PLMN.

13. The apparatus of claim 12, wherein the apparatus is further caused to:

select the second radio access technology which has the highest priority for the current PLMN, wherein the at least one PLMN selector list comprises prioritized at least one radio access technology candidate for the at least one PLMN.

14. The apparatus of claim 13, wherein the apparatus is further caused to:

verify that the selected second radio access technology provides coverage for the current PLMN by applying coverage data, wherein the coverage data indicates which at least one radio access technology in the current geographical area provides coverage for the current PLMN.

15. The apparatus of claim 12, wherein the apparatus is further caused to:

select the second radio access technology from the at least one PLMN selector list having at least one non-prioritized radio access technology candidate for the at least one PLMN; and

select the second non-prioritized radio access technology which provides coverage for the current PLMN on the basis of coverage data, wherein the coverage data indicates which at least one radio access technology in the current geographical area provides coverage for the current PLMN.

16. The apparatus of claim 12, wherein the at least one PLMN selector list is stored in a subscriber identity module coupled to the user terminal.

17. The apparatus of claim 10, wherein the apparatus is further caused to:

select the second radio access technology on the basis of coverage data, wherein the stored information comprises the coverage data indicating which at least one radio access technology is associated with which at least one PLMN in which geographical areas.

18. The apparatus of claim 17, wherein the apparatus is further caused to:

record the coverage data by observing which at least one radio access technology has provided coverage for which of the at least one PLMN along at least part of the trajectory of the user terminal.

19. The apparatus of claim 10, wherein the apparatus is further caused to:

select the second radio access technology on the basis of radio access technology availability information, wherein the stored information comprises the radio access technology availability information indicating which at least one radio access technology is available in which geographical areas.