Patent ID: 8498571

Claim:
A communication device comprising: a communication circuit unit that processes a high frequency signal which transmits data; a high frequency signal transmission path that is connected to the communication circuit unit; a high frequency coupler that receives the high frequency signal and radiates an induction electric field signal of a longitudinal wave; and an antenna that receives the high frequency signal and radiates a radiation electromagnetic field or an electric wave signal of a transverse wave, wherein the high frequency coupler includes: a coupling electrode that is connected to one end of the high frequency signal transmission path and accumulates a charge; a ground that is disposed to face the coupling electrode and accumulates a reflected image charge of the charge; a resonance unit that increases a current flowing into the coupling electrode by installing the coupling electrode at a part where a voltage amplitude of a standing wave generated when the high frequency signal is supplied becomes great; and a support unit that is constituted by a metal line connected to the resonance unit at a nearly central position of the coupling electrode, wherein a microscopic dipole is formed by a line segment connecting a center of the charge accumulated in the coupling electrode to a center of the reflected image charge accumulated in the ground, and wherein the induction electric field signal of the longitudinal wave is output towards the high frequency coupler of a communication partner side which is disposed to face the coupling electrode such that an angle .theta. formed in a direction of the microscopic dipole becomes nearly 0 degrees.