A communication apparatus comprising: a regular optical transceiver including a first number of optical transceivers to each generate a regular subcarrier signal serving as a subcarrier signal; a narrowband optical transceiver including a second number of optical transceivers (21, 22) each capable of generating a narrowband subcarrier signal serving as a subcarrier signal having a narrower frequency band than the regular subcarrier signal; and a subcarrier configuration determiner to determine a configuration of a plurality of componential subcarrier signals in a super-channel signal, based on information on the number of optical filter stages to pass through, which is information on the number of optical filters through which the super-channel signal containing the plurality of componential subcarrier signals passes in a transmission path when the super-channel signal is transmitted to a counterpart communication apparatus, wherein the plurality of componential subcarrier signals consists of the first number of regular subcarrier signals and the second number of narrowband subcarrier signals; wherein the regular optical transceiver is arranged to shift positions of the regular subcarrier signals in the super-channel signal, according to optical frequency shift amounts indicating shift amounts of the plurality of componential subcarrier signals indicated by the configuration determined by the subcarrier configuration determiner, and the narrowband optical transceiver is arranged to shift positions of the narrowband subcarrier signals in the super-channel signal, according to the optical frequency shift amounts. a regular optical transceiver including a first number of optical transceivers to each generate a regular subcarrier signal serving as a subcarrier signal; a narrowband optical transceiver including a second number of optical transceivers (21, 22) each capable of generating a narrowband subcarrier signal serving as a subcarrier signal having a narrower frequency band than the regular subcarrier signal; and a subcarrier configuration determiner to determine a configuration of a plurality of componential subcarrier signals in a super-channel signal, based on information on the number of optical filter stages to pass through, which is information on the number of optical filters through which the super-channel signal containing the plurality of componential subcarrier signals passes in a transmission path when the super-channel signal is transmitted to a counterpart communication apparatus, wherein the plurality of componential subcarrier signals consists of the first number of regular subcarrier signals and the second number of narrowband subcarrier signals; wherein the regular optical transceiver is arranged to shift positions of the regular subcarrier signals in the super-channel signal, according to optical frequency shift amounts indicating shift amounts of the plurality of componential subcarrier signals indicated by the configuration determined by the subcarrier configuration determiner, and the narrowband optical transceiver is arranged to shift positions of the narrowband subcarrier signals in the super-channel signal, according to the optical frequency shift amounts.