Abstract: A cellular telephone includes a receiver for receiving cellular communications and a transmitter for transmitting cellular communications. A controller is coupled to the receiver and the transmitter and controls the receiver and the transmitter based on the command signals. The controller includes a first memory for storing call rate information indicative of rates charged for the cellular communications. A timer provides a timer signal indicative of a time during which the cellular communications take place. The controller determines the amount of currency to be charged for the cellular communications based on the call rate information and the timer signal. An administrator station is provided for loading a threshold amount of currency into the cellular telephone. The entire system can be tracked and managed, and system wide statistics are available to the system operator.

Abstract: A mobile radiotelephone is responsive to user entry of an extension such as the last four digits of a telephone number, to identify a prefix such as the first three digits of a telephone number, for the user-entered extension. By automatically identifying a prefix, the user need not enter all of the numbers for the destination telephone. A default automatic prefix may be stored and retrieved in response to user entry of an extension. Alternatively, in response to user entry of an extension, the stored extensions in a memory such as a speed dialing memory are searched to identify a match to the user-entered extension. The associated prefix for the matched extension is retrieved. Default and speed dialing prefix identification may be combined. Simplified dialing and enhanced user safety are thereby provided.

Abstract: A self-disabling device for a portable terminal used in a mobile telephone network includes a register holding an identification number of the portable terminal and a buffer memory for temporarily storing short information messages transmitted by a control station of the network. One message contains a list of identifier numbers of terminals used fraudulently. A comparator compares the identifier number of the terminal with each of the identifier numbers in the list and transmission of calls by the portable terminal is disabled in response to a positive comparison by the comparator.

Abstract: A mobile unit having a unit for transmitting and receiving signals to and from a base station by radio telephony, an input unit for use in entering information, a display and a control unit, is provided with a first memory in which "unwritten" or "written" is stored as a state of a password for enabling the dial lock, and a second memory in which a password for enabling the dial lock is stored. When a dial lock signal is supplied from the input unit, the control unit writes a password entered at the input unit in the second memory and changes the state of a password in the first memory from "unwritten" to "written." Thereafter, except after providing the password, the mobile unit cannot be used for calling. Moreover, the password cannot be modified.

Abstract: In a mobile telephone device having a preassigned call number and comprising a power supply unit, a keyboard section, a display section, a power key, and a control section, the mobile telephone device transmits, on position registration operation, a position registration signal including the preassigned call number to the base station and receives an information signal from the base station as a result of the position registration operation. The information signal is for representing whether or not the preassigned call number coincides with that of a stolen mobile telephone device. The control section invalidates the operation of the keyboard and the power key and stops display of the display section and then transmitting an alarm signal to the base station on reception of the information signal representing the fact that the preassigned call number coincides with that of the stolen mobile telephone device.