| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical communication system having improved frequency use efficiency by setting an optimal signal bandwidth of a multi-level modulation signal to an optimal value to fit to a frequency interval. <P>SOLUTION: The optical communication system for modulating data by the multi-level modulation scheme includes: a transmission device for mapping an input data to a complex symbol according to a mapping table in which the sequence of the multi-level modulation scheme is described, and converting the real part and the imaginary part of the complex symbol respectively from a digital signal to an analog signal, and modulating the analog-converted signal; and a reception device for converting the received analog signal into a digital signal, and deciding a multi-level modulation scheme with which the converted digital signal is modulated, and determining a complex symbol on the basis of the decision, and restoring an output binary. <P>COPYRIGHT: (C)2013,JPO&INPIT |
