EMERGENCY CALLS FOR INTERNET PROTOCOL MULTIMEDIA SUBSYSTEM (IMS) OVER PACKET SWITCHED CODE DIVISION MULTIPLE ACCESS (CDMA) NETWORKS

摘要

A mobile communication device receives initiation of an emergency call by a user of the mobile communication device, and determines whether a single-carrier radio transmission technology (1xRTT) network is available for the emergency call. The mobile communication device also routes the emergency call over the 1xRTT network when the 1xRTT network is available for the emergency call, and routes the emergency call over an enhanced high rate packet data (eHRPD) network when the 1xRTT network is unavailable for the emergency call.