| 摘要 |
Provided are transmitting, receiving and communication systems of an optical network and a method for modulating a signal. The transmitting system includes: first Passive Optical Network, PON, equipment, configured to output a binary digital signal; and an M-order digital modulator, configured to modulate the binary digital signal into an M-order digital signal, and output the M-order digital signal, wherein each transmission symbol in the M-order digital signal carries information of N = log 2 M bits, where N is a natural number greater than 1 and M is a natural number. By the present invention, the problems of higher using cost of a user and poorer practicability caused by the fact that a binary digital modulation mode is adopted in most of optical communication systems, greater bandwidths are required during transmission and optical transceiver modules with higher transmission rates are required by greater bandwidths is solved, the bandwidths required by transmission are further reduced, and the actual cost of the optical transceiver modules is lowered; and meanwhile, power spectrums can be reshaped by virtue of M-nary characteristics, so that a power spectrum of an RF signal is prevented from being superimposed with a power spectrum of a downlink signal of a PON, and the technical problem of Raman crosstalk is solved. |
