Cell selection in border regions

To prevent battery drain, 3GPP generally mandates that while under international roaming, a cellular device only scan for networks of the foreign country. For example, a US-based cellular device that is roaming in Canada will not generally scan for US service providers so long as it is being served by a Canadian service provider. This sometimes results in the unintended consequence of a cellular device in a border area physically in the home country but nevertheless stuck in international roaming. Techniques of this disclosure provide a mechanism for a cellular device to recognize, through a process of self-learning, its presence in a border region. When a cellular device finds itself in a border region, it intelligently scans for preferred carriers in both home and foreign countries. When not close to a border region, the cellular device scans exclusively for carriers of the country it is currently physically present in

Enhanced OOS Recovery Mitigation During Screen Status Change

A smartphone can reduce power consumption when located in a low service coverage area by determining whether to scan for service based on a screen status of the smartphone. However, in some cases, screen activation does not imply the user is initiating smartphone use, such as when the screen is activated in response to an alarm or a reminder triggered by an application. Smartphone power management is improved by using a proximity sensor to determine whether to initiate a service scan, as well as the type of service scan to initiate

Voice Service Availability Indication for Data Centric Networks on a Mixed-Use Wireless Device

A wireless device, such as a smartphone, includes voice and data capabilities for a user. However, a user interface (UI) on the wireless device shows the signal quality of only the voice service signal. The user does not have information about the signal quality of data service which may be available to the user, creating a frustrating user experience. To improve the user wireless device experience, the availability of data service and the availability of voice service can be displayed in the UI

Self-Optimizing Geofence for Opportunistic Wireless Networks

A method is provided for optimizing a geofence boundary in order to reduce the amount of time between a mobile device entering the geofence and the mobile device connecting to the network. Optimizing a geofence boundary can also reduce battery power used by the mobile device in scanning for network coverage. Once a mobile device is within an area that is covered by a cellular network and has connected to the network, an algorithm is employed that adjusts an edge of a geofence that encompasses some or all of the cellular coverage area. The algorithm moves the edge of the geofence based on the location of the last unsuccessful scan by the mobile device. The algorithm iteratively adjusts the edges of multiple zones of a geofence as the mobile device user moves within the geofence, resulting in a geofence that more closely matches the boundary of actual cellular coverage

Skip Unnecessary Public Land Mobile Networks for Data-Only Subscriber Identity Module

A user equipment (UE) employing a data-only subscriber identity module (SIM) is configured to ignore or skip non-preferred public land mobile networks (PLMNs). For example, the UE is restricted to a predefined list of (preferred) PLMNs stored at the UE. When the UE determines that a registered PLMN or a home PLMN is not available, the UE compares available PLMNs (if any) to the predefined list of PLMNs. If an available PLMN is identified as a preferred PLMN based on the predefined list of PLMNs, the UE selects and attempts to register on the PLMN. However, if no available PLMNs are identified as a preferred PLMN, the UE does not attempt to register with these “non-preferred” PLMNs

Optimized Data Switching for Opportunistic Data DSDS Devices

Dual SIM Dual Standby (DSDS) wireless devices are configured with a primary subscriber identity module (SIM) card providing both voice and data connections on a primary network and a secondary SIM card for providing data-only access on a secondary network. The utilization of wireless network resources by a DSDS wireless device can be enhanced by accounting for congestion on each of the associated networks and data usage of the device to determine whether a switch between networks would be beneficial for device performance

Throttling downlink throughput to mitigate device temperature increase

The temperature of a mobile device can increase due to heavy use, e.g., high-speed downloads, large computational load, etc. Sustained periods of high temperature can damage the mobile device. The techniques of this disclosure reduce downlink throughput upon detection of device temperature that exceeds a threshold. Throughput is reduced, e.g., by signaling the thermal state to the network, by reporting lower channel quality indicator (CQI) values to the network, etc. After the temperature drops to a safe level, throughput is brought back up in a phased manner

INTELLIGENT SIM SWITCHING IN A MULTI-SIM COMPUTING DEVICE

A system is described that enables a computing device (e.g., a mobile phone, a tablet computer, a laptop computer, etc.) to intelligently determine whether to move a data connection from a default data subscriber identity module (DDS) to a non-default data subscriber identity module (non-DDS) when initiating a voice call or during an on-going voice call on the non-DDS in a multiple subscriber identity module (multi-SIM) computing device based on a current state of the computing device. The current state of the computing device may be determined based on various contextual signals, including data usage for each application on the device, the number of foreground applications, the number of background applications, data tethering state, voice call characteristics, connected peripherals, computing device screen state, and/or sensor data generated by one or more sensors (e.g., proximity sensors, near-field microwave sensors, radar, capacitive sensors, etc.) of the computing device. The computing device may analyze these contextual signals to determine a current state of the device and may selectively move the data connection from the DDS to the non-DDS based on this state information

Restricting Low Priority Data Access when Data Quality is Poor

A user equipment (UE) identifies situations in which a less-preferred radio access technology (RAT) camped on a network is unlikely to provide sufficient data throughput for one or more software applications executing at the UE. In such situations, the UE selectively represents the camped RAT as providing voice service only, even when data service is actually available. Alternatively, rather than a blanket prohibition on use of data services in this situation, the high-level operating system (HLOS) of the UE instead may identify software applications that require a data rate higher than that practicable for the less-preferred RAT under the current conditions and selectively bar these identified applications from using the PS data service provided by the less-preferred RAT, while allowing other software applications that have a sufficiently low data rate requirement to utilize the PS service. This prevents the user from attempting to utilize the poor data quality provided by the less-preferred RAT for an application that requires a higher data rate, thus avoiding unnecessary user frustration and excess power consumption from frequent data retransmissions resulting from attempted use of a poor data quality connection

Aggressive Smartphone Thermal Mitigation at High Temperatures

Thermal mitigation at a smartphone is improved by employing an emergency disconnect mode that is entered in response to heat at the smartphone exceeding a specified threshold. In the emergency disconnect mode, the smartphone is disconnected from a cellular network. This allows the components of a radio front-end of the smartphone to be turned off or placed in a low power mode while the smartphone is in the emergency disconnect mode, thereby rapidly decreasing the amount of heat generated at the device and allowing the smartphone to return to a normal mode of operation more quickly