| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent illegal use even after the activation of a portable terminal. SOLUTION: A portable terminal 1 for executing radio communication with a relay center 22 is provided with a processing part 200 for performing the processing of a function provided to the portable terminal 1, a communication part 101 for performing radio communication with the relay center 22, a discrimination part 102 for discriminating whether the portable terminal 1 exists within a range communicable with the relay center 22 and a power source/function limit part 103 for turning on power supply to the processing part 200 to make the portable terminal operative when the discrimination part 102 discriminates the existence of the terminal within the communicable range, stopping the turning ON of power supply to make the portable terminal unusable when the existence of the terminal within the communicable range is not discriminated. Then, it is periodically confirmed whether the portable terminal exists within the radio communicable range after the activation of the portable terminal 1 and when the terminal does not exist within the radio communicable range, the use of the portable terminal 1 is stopped or limited by the power source/ function limit part 103.</p> |
