Patent ID: 8874177

Claim:
A method performed by a mobile device, the method comprising: at a first time: obtaining from a cellular radio subsystem incorporated in the mobile device a first cellular signal strength measurement and identifying to which first cellular signal strength category of a predefined set of cellular signal strength categories the first cellular signal strength measurement belongs; and obtaining from a wireless local area network (WLAN) radio subsystem incorporated in the mobile device a first WLAN signal strength measurement and identifying to which first WLAN signal strength category of a predefined set of WLAN signal strength categories the first WLAN signal strength measurement belongs; waiting a predefined amount of time following the first time; at a second time: obtaining from the cellular radio subsystem a second cellular signal strength measurement and identifying to which second cellular signal strength category of the predefined set of cellular signal strength categories the second cellular signal strength measurement belongs; and obtaining from the WLAN radio subsystem a second WLAN signal strength measurement and identifying to which second WLAN signal strength category of the predefined set of WLAN signal strength categories the second WLAN signal strength measurement belongs; comparing the first cellular signal strength category to the second cellular signal strength category; comparing the first WLAN signal strength category to the second WLAN signal strength category; in the event that both (i) the first cellular signal strength category represents a stronger cellular signal strength than the second cellular signal strength category and (ii) the first WLAN signal strength category represents a weaker WLAN signal strength than the second WLAN signal strength category, determining that the obtained measurements are indicative of an outdoor-to-indoor transition of the mobile device and increasing a background scanning frequency of the WLAN radio subsystem.