Patent ID: 11888521
Assignee: PANASONIC HOLDINGS CORPORATION
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 5:
6. A slave station device comprising:
a receiver which, in operation, receives an optical signal via a fronthaul; and
a processor which, in operation, identifies a subcarrier modulation signal based on an in-phase (I) component and a quadrature-phase (Q) component of the subcarrier modulation signal mapped to the optical signal, wherein:
the subcarrier modulation signal is coded in a first quadrature amplitude modulation scheme having a plurality of signal points,
the optical signal is coded in a second quadrature amplitude modulation scheme having a plurality of candidate signal points, the second quadrature amplitude modulation scheme having a higher modulation multilevel number than the first quadrature amplitude modulation scheme, and
the processor sets each of the plurality of candidate signal points of the optical signal to a corresponding signal point of the plurality of signal points of the subcarrier modulation signal, a distance from the each of the candidate signal points of the optical signal to the corresponding signal point being a shortest distance in an IQ plane of the subcarrier modulation signal.