Research on High-speed DPSK and Coherent Optical Communication Systems
|Course||Communication and Information System|
|Keywords||DPSK modulation Coherent detection Digital coherent optical receiver Linear optical sampling|
In order to meet the growing demand for bandwidth , commonly used in modern high - speed large-capacity optical transmission technology ary modulation scheme to improve the spectrum utilization . The study shows that the DPSK modulation method exhibit far superior OOK modulation scheme of the transmission performance and a better resistance to non-linear performance . RZ-DPSK is considered to be the modulation method of the next generation of high speed transmission systems Select . Coherent optical receiver ary modulation signal processing techniques and linear optical sampling measurement technology has also become a hot research and development in the field of optical communications . High sensitivity, the receiver of the coherent optical communication system , the transmission of long distance relay , more conducive to make full use of the broadband of the optical fiber , to improve the communication quality . Linear optical sampling technique is suitable for high speed PSK , DPSK optical signal measurement technique, using sampling techniques based on coherent detection of the linear light is measured in the high bit rate PSK, DPSK signal waveform and eye diagram . Therefore , it is necessary depth exploration of the DPSK modulation method and the PSK , DPSK Coherent detection communication system . The papers on the use of arms MZM DPSK signal modulation , the new digital coherent optical receiver system and linear optical sampling technology has done a lot of research , the main work is the following : ( 1 ) to study the use of arms the MZM phase modulator modulated DPSK optical signal and the DPSK optical signal receiving the principle of the the MZDI balanced detection . The use of Optisystem light simulation software simulation DPSK optical signal MZM modulation MZDI - balance detection receiver . (2) study the basic principles of coherent optical detection , schematic design homodyne detection circuit and DSP - based digital coherent receiver , and the derivation of the relevant formulas . ( 3 ) study the linear optical sampling principles and to achieve linear optical sampling conditions and linear optical sampling noise analysis derived formula . ( 4 ) design a linear optical sampling experiments Figure , Figure Hybrid linear optical sampling simulation based on the experimental principle .