Method and apparatus for efficient network scanning
AssigneeBlackBerry Limited
InventorYiu Ming Lam
Life of this patent
Estimating the term…
Abstract
A method and apparatus for efficient network scanning that selects candidate frequencies based upon the frequency bands that were noted as being active during a previous network scan. A mobile device performs a full network scan on power up or on radio cycle and determines the available active bands. This information is stored as active band information on the device. When the device loses coverage on a selected one of the bands, then it identifies a candidate frequency based upon the stored active band information and attempts to locate a suitable network on the candidate band.
Claims19
A method of frequency band scanning of multiple supported bands to obtain service for a mobile device, the supported band including first bands from a first network frequency plan and second bands from a second network frequency plan, the first bands being different from the second bands, the method comprising:
- scanning, from the mobile device, to identify which of the first bands and second bands are active, wherein a band is active if the mobile device could obtain wireless services on that band;
- establishing a connection on one of the bands identified as being active;
- storing, in memory on the mobile device, a list of the bands identified as being active during the scanning, including the one band on which the connection was established and a band on which the mobile device did not obtain wireless services;
- in response to a loss of coverage on the one band, selecting another band from the list of bands, irrespective of the frequency plan to which said another band belongs;
- and
- scanning the selected band, and
- wherein the one band is a member of said first network frequency plan and wherein the selected band is a member of said second network frequency plan, and wherein said list excludes another band within said first network frequency plan.
A mobile electronic device, comprising:
- a communications subsystem for frequency band scanning of multiple supported bands to obtain service for a mobile device, the supported band including first bands from a first network frequency plan and second bands from a second network frequency plan, the first bands being different from the second bands;
- memory;
- and
- a processor connected to said memory and to said communications subsystem for controlling operation of said communications subsystem, wherein the processor is configured to
- scan, at the mobile device, to identify which of the first bands and second bands are active, wherein a band is active if the mobile device could obtain wireless services on that band,
- establish a connection on one of the bands identified as being active,
- store in memory a list of the bands identified as being active during the scanning,
- including the one band on which the connection was established and a band on which the mobile device did not obtain wireless service,
- in response to a loss of coverage on the one band, select another band from the list of bands, irrespective of the frequency plan to which the another band belongs, and
- scan the selected band, and
- wherein the one band is a member of said first network frequency plan and wherein the selected band is a member of said second network frequency plan, and wherein said list excludes another band within said first network frequency plan.
A mobile electronic device, comprising:
- a communications subsystem for frequency band scanning of multiple supported bands to obtain service for a mobile device, the supported band including first bands from a first network frequency plan and second bands from a second network frequency plan, the first bands being different from the second bands;
- memory;
- and
- a network locator component configured to
- identify, at the mobile device, which of the first bands and second bands are active,
- wherein a band is active if the mobile device could obtain wireless services on that band,
- instruct the communications system to establish a connection on one of the bands identified as being active,
- store in memory a list of the bands identified as being active including the one band on which the connection was established and a band on which the mobile device did not obtain wireless service,
- select another band from the list of bands, irrespective of the frequency plan to which the another band belongs, in response to a loss of coverage on the one band, and
- scan the selected band, and
- wherein the one band is a member of said first network frequency plan and wherein the selected band is a member of said second network frequency plan, and wherein said list excludes another band within said first network frequency plan.
Dependencies are inferred from the claim text.