Patent ID: 8706029

Claim:
A communication system comprising: a transmitter including a transmitting circuit to generate radio frequency signals for transmitting data and a first electrical field coupling antenna to transmit the radio frequency signals as an electrostatic field or an inductive electrical field; and a receiver including a second electrical field coupling antenna and a receiving circuit to perform a reception process on radio frequency signals received by the second electrical field coupling antenna, wherein each of the first and second electrical field coupling antennas includes: a plate coupling electrode, a resonant portion to strengthen electrical coupling between the plate coupling electrodes, a connection portion located in a substantial center position of the resonant portion and connecting the plate coupling electrode and the resonant portion, and a radio wave absorber placed near the coupling electrode, wherein the radio wave absorber covers at least a surface of the plate coupling electrode or the connection portion; and wherein the radio frequency signals are transmitted as an electric-field longitudinal wave component through electrical field coupling between the plate coupling electrodes of the first and second electrical field coupling antennas, the plate coupling electrodes facing each other.