Communication apparatus power line communication method and power line.

A communication apparatus power line (100) that transmits and receives a signal having a plurality of subcarriers via a power line, the apparatus including communication power line (100): a connection unit transmission line (101) receiving the signal having the plurality of subcarriers via the power line; one noise calculator (115) calculates a noise level corresponding to each of the plurality of subcarriers; a determination unit (115) that determines a modulation scheme employed for each of the plurality of subcarriers based on the noise level; a calculating transmission rate (116) that calculates a transmission rate corresponding to a data volume per symbol based on the level corresponding to each of the subcarriers noise; and a display (117) having the transmission rate calculated by the transmission rate calculator.