Fang Wenjing1, Bai Chenglin1, Zhang Xia1, et al. Commonly used modem structure establishment and simulation of optical MDPSK[J]. 2012,(4):13-15. DOI: 10.13756/j.gtxyj.2012.04.008.
The novel phase modulation format technology is important to optical transmission systems as it can effectively reduce the damages in optical transmissions.This paper theoretically analyzes the principles of modulation and demodulation of optical M-ary Differential Phase Shift Keying(MDPSK)
establishes its common modem structure and derives for the first time its general and demodulation formulas.Finally
it obtains by using MATLAB software the spectrum after modulation and eye diagram after demodulation
taking DQPSK
8DPSK and 16DPSK that are based on Carrier-Suppressed Return-to-Zero(CSRZ with duty cycle of 67%) as the examples.The simulation results show that the spectral width of MDPSK modulation format gradually becomes narrower with the increase of M