| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a terminal that generates an electromagnetic field for communication with at least one transponder, and to provide a method for controlling this terminal. SOLUTION: The terminal is provided with an oscillation circuit, that is excited by a remote supply signal from the transponder, a phase demodulator for detecting data sent from the transponder, a means for regulating a signal phase of the oscillation circuit of the terminal to be a reference value, a means for measuring a variable linked with a current and a voltage of the oscillation circuit, and a means that compares the present value of the variable with a prescribed value to decide whether the transponder is present.</p> |
