Enhanced mobile network system acquisition using scanning triggers

• US 8,908,561 B2
• Filed: 09/18/2009
• Issued: 12/09/2014
• Est. Priority Date: 09/18/2009
• Status: Expired due to Fees

• Current Assignee: General Motors LLC (General Motors Company)
• Original Assignee: General Motors LLC (General Motors Company)
• Inventors: Krause, Kevin R., Kassam, Ayaz S., Doherty, James, Yi, Ki Hak
• Primary Examiner(s): Towfighi, Afshawn
• Assistant Examiner(s): WILLIAMS, JENEE LAUREN
• Application Number:
  US12/562,698
• Publication Number:
  US 20110069680A1
• Time in Patent Office: 1,908 Days
• Field of Search: 370/254
• US Class Current: 370/254
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A system and method for executing network acquisition employ a triggered scan for network acquisition regardless of the recorded optimal nature of the current network. In general, when one or more predefined conditions occur, a network scan is initiated to identify another network, if any, that is more optimal than the current network. Example trigger conditions include failed registration attempts, exceeding a predetermined distance threshold, entry to or exit from a pre-determined region, excess CDMA Chip delay, and others. Triggers may be used singly or in Boolean combinations. In this way, network scanning occurs when it may be beneficial, but will not be initiated too frequently or in situations where connectivity may not actually be suboptimal. This triggered scan provides improved connectivity, and can allow the device to make and receive calls in locations where it would otherwise not have been possible.

Claims

1. A method of providing improved network connectivity to a wireless device by identifying an alternative cellular network to replace a current cellular network, the device being associated with a Preferred Roaming List (PRL), the method comprising:

determining, by the wireless device, while idling on the current cellular network, status of a plurality of preconfigured trigger conditions, wherein combinations of at least two preconfigured trigger conditions define circumstances under which a network acquisition scan is to be undertaken, and wherein a preconfigured trigger condition in each of the combinations is detection of local satellite radio repeaters;

initiating, in response to detecting at least one of the combinations of preconfigured trigger conditions is met, a scan of one or more alternative networks, the scan including at least one network that is not listed in the PRL, wherein none of the combinations of preconfigured trigger conditions can be met when no local satellite radio repeaters are detected;

identifying, during the scan, an alternative network that supports a service level that is higher than the current cellular network; and

disassociating from the current cellular network and acquiring the alternative network.

2. The method according to claim 1, wherein the preconfigured trigger conditions further include at least one of:

distance of the wireless device from a base station being greater than a preconfigured threshold, distance of the wireless device from a site of a prior acquisition task being greater than a preconfigured threshold;

exiting from a preconfigured geographical region;

Code Division Multiple Access (CDMA) chip delay being greater than a preconfigured amount;

a received signal strength being less than a threshold value; and

Ec/Io being above a preconfigured threshold.

3. The method according to claim 2, wherein the preconfigured amount of CDMA chip delay is 100 μ

s.

4. The method according to claim 1, wherein the preconfigured trigger conditions further include:

distance of the wireless device from a base station being greater than a preconfigured threshold, wherein the distance of the wireless device from the base station is determined by comparing a current latitude/longitude with a base station latitude/longitude included in a sync message.

5. The method according to claim 1, wherein the preconfigured trigger conditions further include:

distance of the wireless device from a site of a prior acquisition task being greater than a preconfigured threshold, wherein the distance of the wireless device from the site of the prior acquisition task is determined by recording a latitude/longitude where the prior acquisition task was performed and comparing a current latitude/longitude to the recorded latitude/longitude.

6. The method according to claim 1, wherein the preconfigured trigger conditions further include:

received signal strength being less than a preconfigured signal value and Ec/Io being above a preconfigured threshold, and wherein the plurality of combinations includes a combination of preconfigured trigger conditions where;

for a duration exceeding a threshold duration, the received signal strength is less than a preconfigured signal value and the Ec/Io is above a preconfigured noise value; and

satellite radio is available.

7. The method according to claim 6, wherein the threshold duration is about 60 seconds and the preconfigured signal value is about −

100 dbm.

8. The method according to claim 6, wherein the preconfigured noise value is about 7.

9. The method of claim 1, further comprising placing a wireless call on the alternative network that could not be placed on the current network.

10. The method of claim 1, further comprising receiving a call on the alternative network that could not be received on the current cellular network.

11. The method according to claim 1, wherein the alternative network is not listed in the PRL.

12. The method according to claim 1, wherein the alternative network is listed in the PRL, but is associated with a lower priority in the PRL than the current cellular network.

13. The method according to claim 2, wherein the preconfigured trigger conditions are user-selectable.

14. A non-transitory computer-readable medium having thereon computer-executable instructions for providing improved network connectivity to a wireless device by identifying an alternative cellular network to replace a current cellular network, the device being associated with a Preferred Roaming List (PRL), the computer-executable instructions comprising instructions for:

determining, while idling on the current cellular network, status of a plurality of preconfigured trigger conditions, wherein combinations of at least two preconfigured trigger conditions define circumstances under which a network acquisition scan is to be undertaken, and wherein a preconfigured trigger condition in each of the combinations is detection of local satellite radio repeaters;

initiating, in response to detecting at least one of the combinations of preconfigured trigger conditions is met, a scan of one or more alternative networks, the scan including at least one network that is not listed in the PRL, wherein none of the combinations of preconfigured trigger conditions can be met when no local satellite radio repeaters are detected;

identifying an alternative network during the scan that supports a service level that is higher than the current cellular network; and

disassociating from the current cellular network and acquiring the alternative network.

15. A vehicle-borne telematics unit for communicating over one or more wireless networks, the telematics unit comprising:

a processor for operating the telematics unit in accordance with computer-readable executable instructions; and

a memory associated with the processor and having thereon computer-executable instructions for identifying an alternative cellular network to replace a current cellular network that was selected based on a Preferred Roaming List (PRL), the instructions including instructions for;

determining, while idling on the current cellular network, status of a plurality of preconfigured trigger conditions, wherein combinations of at least two preconfigured trigger conditions define circumstances under which a network acquisition scan is to be undertaken, and wherein a preconfigured trigger condition in each of the combinations is detection of local satellite radio repeaters,

initiating, in response to detecting at least one of the plurality of combinations of preconfigured trigger conditions is met, a scan of one or more alternative networks, the scan including at least one network that is not listed in the PRL, wherein none of the combinations of preconfigured trigger conditions can be met when no local satellite radio repeaters are detected,

identifying an alternative cellular network that supports a service level higher than the current cellular network, and

disassociating from the current cellular network and acquiring the alternative cellular network.