WDM And PDM Signal Processing For Advancd Modulation Formats

In recent years, optical fiber communication technology has developed rapidly, with thethe reasearch for ultra high speed, large capacity, long distance optical transmission networktechnology, advanced modulation formats have obtained much more attention at home andabroad for their stronger non-linear resistance and higher spectrum efficiency than thetraditional format. At the same time, more and more signal multiplexing technologies havebeen applied to increase the capacity of the communication systems. Therefore, the signalprocessing such as regeneration, format conversions for these multi-demensionalmultiplexed new formats are deserved to be further investigated.Sponsored by the National Basic Research Program of China (973) and the NationalNatural Science Foundation project, the all-optical signal processing for themulti-demensional multiplexed advanced modulation formats, including format conversionand signal regeneration of the wavelength division multiplexed (WDM) and polarizationmultiplexed (PDM) signals, using the active nonlinear devices-semiconductor opticalamplifier (SOA) and passive optical filters, are fully and systemically investigated.Overview of the full text, main research results are as follows:(1) The significance and principle of all-optical signal processing for the advancedmodulation formats are discussed, the method of the signal decomposition to deal with theformat conversion is suggested. At the same time, the ideas about multi-dimensionsmultiplexing signal parallel processing are put forward, and the method about parallel signalprocessing is discussed by the analysis of the processing about the WDM and PDM signals,which enable the subsequent experimental schemes possible.(2) The8channel40Gb/s non-return-to-zero on-off keying (NRZ-OOK) to return-to-zeroon-off keying (RZ-OOK) format conversion based on a phase modulator (PM) and a delayinterferometer (DI) is successfully implemented.(3) The amplitude regeneration of6channel40Gb/s return-to-zero phase-shift keying(RZ-PSK) signals can be achieved simultaneously.(4) An amplitude regeneration scheme of80Gb/s return-to-zero quadrature differentialphase-shift keying (RZ-DQPSK) signal using the gain saturation effect of a SOA is proposed,and the possible solution for mulit-channel processing is also investigated. (5) The WDM and PDM mixed multiplexing signal format conversion program isstudied.4-wavelength20Gbaud wavelength division multiplexed and polarization divisionmultiplexed RZ-OOK to NRZ-OOK, RZ-DPSK to NRZ-DPSK and RZ-QPSK toNRZ-QPSK conversions have been achieved respectively.(6) The WDM and PDM mixed multiplexing signal regeneration scheme is studied. Anamplitude regeneration scheme of20Gbaud WDM and PDM RZ-PSK signal using a SOA isproposed, and the amplitude regeneration for multi-dimensional multiplex signal can beachieved simultaneously.