SIGNAL MODULATION METHOD, SIGNAL DEMODULATION METHOD, SIGNAL MODULATION APPARATUS, SIGNAL DEMODULATION APPARATUS AND SIGNAL TRANSMISSION SYSTEM

摘要

The present invention discloses a signal modulation method, including: demultiplexing an input signal into 2N sub-signals; grouping every two of the 2N sub-signals into a pair; performing filtering on two sub-signals in each pair; performing carrierless amplitude phase (CAP) modulation on the two sub-signals in each pair; modulating the two sub-signals in each pair to a same frequency band, to generate N pairs of CAP signals, where frequency bands of different pairs of sub-signals are different, and a spacing between center frequencies of two neighboring frequency bands is greater than or equal to an average value of baud rates of sub-signals corresponding to the two neighboring frequency bands; and combining the N pairs of CAP signals, and performing electro-optic modulation on a signal obtained after the combining. A signal demodulation method corresponding to the signal modulation method is further disclosed.

主权项

1. A signal modulation method, comprising:
demultiplexing an input signal into 2N sub-signals; grouping every two of the 2N sub-signals into a pair, performing filtering on two sub-signals in each pair, performing carrierless amplitude phase (CAP) modulation on the two sub-signals in each pair, and modulating the two sub-signals in each pair to a same frequency band, to generate N pairs of CAP signals, wherein frequency bands of different pairs of sub-signals are different, two sub-signals in each pair of CAP signals are orthogonal to each other, and a spacing between center frequencies of two neighboring frequency bands is greater than or equal to an average value of baud rates of sub-signals corresponding to the two neighboring frequency bands; and combining the N pairs of CAP signals and performing electro-optic modulation on a signal obtained after the combining, wherein N>1.