摘要 |
<p>A detachable IC card (2a) applicable to a portable data processing device referred to as an "electronic organizer" is disclosed. The IC card is formed of microstrip lines formed on a dielectric substrate (281). An antenna (201a) receives an unmodulated carrier signal (20a) externally applied and guides the received signal to microstrip lines (212a1, 212a2) for impedance conversion. Cathode potential of a diode is varied in response to a data signal outputted from a CPU (222a), so that the barrier capacitance of the diode varies. Accordingly, the carrier is reflected according to the data signal and radiated toward the electronic organizer main body through the antenna. An oscillator for data transmission is not required in the IC card, so that an internal buttery having a large capacitance is not required, either. As a result, without increasing the size and weight of the device, data transmission by radio from the IC card can be accomplished. <IMAGE></p> |