| 摘要 |
PROBLEM TO BE SOLVED: To provide radio communication equipment in which a communication range is extended with small power consumption and miniaturization and light weight configuration are easily realized. SOLUTION: In a memory card that receives and rectifies a carrier sent from a data reader to generate an operating power and a reference clock so as to send ID data synchronously with the reference clock, an antenna B2 for data transmission is made up of an LC resonance circuit consisting of a capacitor C4 and a coil L4. In the case of sending data, a modulation circuit 38 outputs a drive signal Sb with a prescribed pulse width Ton only when the transmission data are '1' and the drive signal turns on a switching element SW. As a result, energy is stored in the LC resonance circuit when the switching element SW is closed and after the switching element SW is open, the LC resonance circuit is resonated by the energy and the coil L4 emits a radio wave with a resonance frequency. |
