COMMUNICATION SYSTEM AND COMMUNICATION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a communication system and a communication method, which can avoid deterioration of transmission efficiency even if an error correction encoding system is applied.SOLUTION: A communication system includes: a PON for connecting one OLT and a plurality of ONUs via an optical power splitter; hierarchical modulation means for transmitting a hierarchical modulation signal obtained by multiplexing downlink data to the ONUs from the OLT; data distribution means for distributing the downlink data to one of hierarchies of the hierarchical modulation signal; and error correction means for setting at least one of an error correction encoding system and redundancy of the error correction encoding system for each hierarchy to which the data distribution means distributes the downlink data.