SIGNAL COUPLING DEVICE

摘要

In a capacitive coupler (CCU) 100 used in a power line communication system that performs communication by putting a high-frequency signal on a power line (8), increasing the capacitance of a high-voltage capacitor (1) in order to increase the coupling efficiency in the low-frequency region of the high-frequency signal has been problematic, for example, in that the cost of the capacitor is increased and the breakdown voltage is lowered. In a signal coupling device of this invention, a drain coil (2) used in the CCU (100) is wound around a magnetic core (21) to match a frequency in the characteristic region in which the Q value of the complex permeability of a magnetic material constituting the magnetic core (21) increases with a frequency in the low-frequency region of the high-frequency signal. This enables the coupling efficiency in the low-frequency region of the high-frequency signal to increase, so that a high coupling efficiency is obtained in a wider frequency range.