A communication device includes a communication circuit unit processing a high-frequency signal, a transmission path connected to the communication circuit, a ground, a coupling electrode supported so as to face the ground and to be separated by a height negligible with respect to a wavelength of the high-frequency signal, a resonating unit increasing a current flowing into the coupling electrode via the transmission path, and an extended section formed of a conductor disposed near a front of the coupling electrode with an angle θ formed relative to a direction of a microdipole being approximately 0 degree, the microdipole being formed of a line segment connecting a center of charges stored in the coupling electrode and a center of mirror-image charges stored in the ground, the conductor extended in a lateral direction approximately orthogonal to a propagating direction of an electric-field signal occurring from the front of the coupling electrode.