| 摘要 |
PROBLEM TO BE SOLVED: To efficiently supply power to a handset even if the handset is cordless, and to produce an audio signal transmitter/receiver circuit with low cost. SOLUTION: A master device body 2a includes a power/audio transmitter circuit 11 which transmits a power and an audio signal to the handset 2b, and a master device receiver circuit 12 which receives an audio signal transmitted from the handset 2b. The handset 2b includes a power/audio receiver circuit 16 which receives the power and audio signal from the master device body 2a, an electrical double-layer capacitor 18 which stores the received power, and a handset transmitter circuit 17 which transmits an audio signal to the master device body 2a. The power/audio transmitter circuit 11 and the power/audio receiver circuit 16 use a loop coil antenna to transmit and receive the power by electromagnetic coupling caused by electromagnetic waves of 455 kHz, and perform amplitude modulation on the electromagnetic waves to transmit an audio signal from the master device body 2a to the handset 2b. COPYRIGHT: (C)2011,JPO&INPIT |
