Abstract: In a mobile terminal including at least two CPUs and a shared memory resource, a CPU executing real-time code has priority access to the memory over a CPU executing non-real-time code. In one embodiment, real-time code and non-real-time code are located in separate regions of logical memory, and a memory management unit between the CPUs and the shared memory resource partially decodes the address of a memory access request, granting higher priority access to the CPU executing real-time code. In another embodiment, each CPU provides a priority signal upon requesting access to the shared memory resource, and access is granted according to the requested priorities.

Abstract: A method of interpreting location area information data in a satellite/terrestrial dual mode mobile terminal is provided, with the mobile terminal in the satellite mode and communicating with a satellite system. The method includes the steps of determining if a most recent registration of the mobile terminal was accomplished in the satellite or terrestrial mode and, if it is determined that the most recent registration of the mobile terminal was accomplished in the terrestrial mode, then determining if (1) a satellite operator ID broadcast by the satellite system matches a satellite operator ID from a most recent satellite location update of the mobile terminal, and (2) a satellite beam pair in a satellite spotbeam pair list broadcast by the satellite system matches a satellite beam pair in a satellite spotbeam ID from a most recent satellite location update of the mobile terminal.

Abstract: A user terminal is operable to acquire service in a satellite mobile communication network in which plural service providers each communicate via satellite with users on one or more spotbeams each having a select frequency. The user terminal comprises a communication system including a transmitter and a receiver for communicating via a spotbeam. A memory stores frequency information. The frequency information identifies carrier frequencies associated with the spotbeams in the network. The memory further stores identification information identifying a service provider associated with each carrier frequency. A communication controller is operatively associated with the communication system and the memory for selecting a spotbeam carrier frequency to communicate on, the communication controller utilizing identification information to select the spotbeam carrier frequency.

Abstract: A multi-mode mobile terminal having a subscriber identity is provided which uses knowledge of communications network supported service levels to navigate to a communication mode allowing the greatest possible service availability when the subscriber identity in at least one of the network modes is invalid. The mobile terminal may not only provide the ability to switch communication service from a current mode to an alternative mode to process emergency calls but may also restrict user operations on a communications network based on the services available without a valid subscriber identity. Operations of the mobile terminal invention may be supported by service level information on various communication service providers contained in memory within the mobile terminal or be obtained by the mobile terminal from the networks.