Communication device, a communication system, and communication method

A communication apparatus may include at least one connection terminal configured to connect with at least one external power line coupled to an external apparatus, at least one internal power line configured to carry power and a communication signal to the at least one connection terminal, and a wireless communication circuit connected to the at least one internal power line. The wireless communication circuit may have an input configured to receive the power and the communication signal from the at least one internal power line, and may be configured to separate the communication signal from the power, and to wirelessly transmit the communication signal to the external apparatus. A communication method may include transmitting power and a communication signal via a power line, separating the communication signal from the power via a circuit connected to the power line, and wirelessly transmitting the separated communication signal via a communication antenna.