| 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, 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, where N>1. A signal demodulation method corresponding to the signal modulation method is further disclosed. A signal modulation system and a signal demodulation system are further disclosed. Compared with a conventional technology, the signal modulation method, the signal demodulation method, the signal modulation apparatus, and the signal demodulation apparatus of the present invention can better utilize bandwidth. |
