To provide a communication channel system and the device capable of improving frequency utilization efficiency and reducing an equipment cost by inserting low-speed data to high-speed data and performing communication.

In a transmitter, the high-speed data among different communication speeds are encoded, and for the data at the prescribed position of the encoded high-speed data, exclusive OR with the low-speed data different from the high-speed data is attained or the data for transmission composed by being replaced with the low-speed data are transmitted. In a receiver, the data decoded in an error correction decoding part 101 are outputted as the high-speed data, and corresponding to the data for the transmission, the exclusive OR of the data at the prescribed position of the data corrected and decoded in the error correction decoding part 101 and the data before correction is attained or the data at the prescribed position are taken out from the data inputted to the error correction decoding part 101 and the low-speed data are outputted.