Abstract: A mobile terminal for use in a mobile communications system includes a SIM card storing subscriber related data. For security, the SIM card performs secret cryptographic calculations with secret numbers. Secret information is hidden from outside observation by scheduling the calculations using a precomputed, fixed randomization schedule in such a way that externally observable parameters of the device cannot be associated to particular pieces, bits, symbols or values of the secret information.

Abstract: A method and system for performing cryptographic calculations on a bitstring using secret information. A cipher key is manipulated to obtain a modified cipher key. An indicator word is generated that corresponds to the modified cipher key and includes a plurality of indicator bits. A first product is computed with an insecure processor as a function of the bitstring and the modified cipher key. A second product is computed with a secure processor as a function of the bitstring and the indicator. A final product is then computed as a function of the first and second products.

Abstract: In a dual-mode satellite/cellular phone system, a user has the option of placing or receiving calls to and from the satellite network with either the cellular/PCS phone or the fully self-contained, stand-alone satellite phone. If the user places or receives a satellite call with the cellular/PCS phone, the communication signals to and from the cellular/PCS phone will first be received from or transmitted to the satellite phone over a short-range, low-power communication link. The satellite phone, in turn, communicates directly with the satellite network from a location that is within a short range of the cellular/PCS phone, and from a location that preferably has a direct line-of-sight with the one or more satellites that make up the satellite network.

Abstract: A method and apparatus for effectuating communication between a mobile telephone and at least one communication network not supported by the mobile telephone. A converter interfaces to a mobile telephone to effectuate communication between the mobile telephone and the communication network.The converter includes a controller for controlling operation of the converter and further for selecting a communication network for communicating with the mobile telephone. Communication protocol functionality within the mobile computer effectuates communication between the mobile telephone and the selected communication network and an interface provides for communication between the mobile telephone and the communication network.

Abstract: In a wireless terminal adapted to operate according to more than one air interface protocol, processing circuits are provided to process signals received by the terminal or to be transmitted by the terminal according to the respective protocol. One of the processing circuits is chosen to be connected to user interface equipment of the terminal to communicate with that equipment also on behalf of the other processing circuits according to a user interface equipment signal format. The other processing circuits communicate with that one processing circuit via a bus according to a bus signal format. The one processing circuit converts the bus signal format to the user interface equipment signal format and vice versa when the terminal is operating according to the protocol of any of the other processing circuits (2-4).

Abstract: A recyclable cellular telephone is disclosed having an inner rigid cellular electronics supporting frame member surrounded by a replaceable outer cover. The telephone is acquired having a limited period of use. The electronics of the telephone operate to disable the telephone following expiration of the period of use. Following expiration of the period of use, the telephone is returned for refurbishment where the outer cover is stripped and replaced and the electronics tested before being recycled with a new period of use for an another acquisition. The cellular network supporting telephone operation also monitors the period of use, disabling telephone access to the network following expiration. Directory numbers are selectively assigned to the recyclable telephones from a pool of available numbers, with assigned numbers returned to the pool after expiration of a predetermined period or telephone deactivation for re-use by another recyclable telephone.