High-frequency coupler and communication device

A communication device comprising:

• a communication circuit unit to perform a process of a high-frequency signal transmitting data;
• a transmission path of a high-frequency signal connected to the communication circuit unit;
• a ground;
• a coupling electrode which faces the ground and is supported so as to be separated by a negligible height with respect to a wavelength of the high-frequency signal;
• and
• a resonating unit to increase a current flowing into the coupling electrode via the transmission path,
• wherein the coupling electrode has bent portions in places where charges with a first polarity are accumulated so that charges with a second polarity are gathered in a front face toward a radiating direction of an electric field when the high-frequency signal is input to the coupling electrode via the transmission path and a standing wave occurs, and
• wherein an infinitesimal dipole constituted by a line connecting a center of the charges accumulated in the coupling electrode and a center of mirror-image charges accumulated in the ground is formed, and the high-frequency signal is transmitted toward a high- frequency coupler of a communication partner side arranged to face each other so that an angle θ formed in a direction of the infinitesimal dipole is substantially 0 degrees.