COMMUNICATION SYSTEM, TRANSMISSION DEVICE, AND RECEPTION DEVICE

摘要

In the present invention, either a communication device (100) or another communication device (200) is provided with a DC power source (110) that: generates a direct current, for serial communication, from AC power that is supplied by an AC power source (600) via a power line (510) and a common use line (530); and sends the generated direct current through a current loop. Either the communication device (100) or the other communication device (200) is provided with an adjustment unit (160) that adjusts the impedance between a signal line (520) and the common use line (530) in accordance with the voltage between the signal line (520) and the common use line (530).