Patent ID: 8023890

Claim:
A communication system, comprising: a transmitter including a transmission circuit unit configured to generate a radio-frequency signal for transmitting data and an electric-field-coupling antenna configured to transmit the radio-frequency signal as an electrostatic field or an induced electric field; a receiver including an electric-field-coupling antenna and a reception circuit unit configured to receive and process the radio-frequency signal received by the electric-field-coupling antenna; and an impedance matching unit configured to make an impedance of the electric-field-coupling antenna of the transmitter equal to an impedance of the electric-field-coupling antenna of the receiver, wherein: the radio-frequency signal is transmitted by electric-field coupling between the electric-field-coupling antennas, facing each other, of the transmitter and the receiver; and the radio-frequency signal is transmitted by a longitudinal wave component of the electrostatic field or the induced electric field.