Generation Of100Gb/s High Speed Optical Signal

With the rapid development of the society and the appearment of new technologies, therequirement for information exchange and communication capacity has been increasedcontinuously. Dense wavelength division multiplexing (DWDM) technology is widely usedto increase the communication capacity by increasing the number of the channels and thespectrum efficiency. At the same time, the speed of single channel is increased continuously.Unfortunately, generation of high speed optical signal higher than40Gb/s based on simplemodulation format, for example, the On-Off-Keying (OOK), is very difficult due to thelimitation of electronic bottleneck. So how to improve the speed of single channel with thelimited electronic bitrate is a very important topic. Supported by National Basic ResearchProgram of China (Grant No.2011CB301704), we focuses on the investigation of generationof100Gb/s high speed optical signal. The main contents and achievements are listed asfollows:(1) An overview of the research on the generation of high speed optical signal wasgiven. Two main methods of generation of high speed optical signal, high order modulationformat and optical time division multiplexing (OTDM), were analyzed. In this thesis, wechoosed Dual-Polarization Quadrature Phase Shift Keying (DP-QPSK) as the high ordermodulation format, and the ultra-short pulse source of OTDM came from a pulsecompression system.(2) Analysis of the principle of generation of DP-QPSK has been made, and the schemebased on discrete devices was choosen to be used in this paper in consideration of our specialdemand and the condition we have. We also analyzed the operation principle of three keyparts of the system, IQ modulator, electric amplifier and auto-bais control. By optimizing theoperation parameters, the system was built and100Gb/s DP-QPSK was generatedsuccessfully. Finally, the system was made into a pluggable instrument.(3) Many kinds of existing optical pulse compression technologies were analyzed intheory, including chirped pulse compression, soliton effect pulse compression, adiabaticsoliton pulse compression, pre-chirped pulse compression, and so on. We also built mathematical models and completed numerical simulation for these schemes based onMATLAB. Some thchnologies of pedestal suppression or remove was analyzed briefly.(4) We analyzed characteristics of all kinds of technologies mentioned above andproposed a new pulse compression scheme by combining several schemes and optimizingthe parameters. We analyzed the principle of the scheme and proved it through simulationwith MATLAB and OPTISYSTEM. We built the system successfully and a0.98psultra-short pulse was gained based on the system. Several methods for improving the systemto get narrower pulse were proposed in theory, which was proved by some experimentalresults. A70nm region was found by theoretical analysis and experiment, where the systemwas insensitive to the operation wavelength. Then the system was extended tomulti-wavelength pulse compression, and four short pulses with full width at half maximumof2.8,2.9,2.6and2ps were generated simultaneously. Finally, we gained160GHz opticalsignal with good quality based on our compression pulse and a OTDM system, and the timeslot between adjacent pulses was wide enough for further division to get higher speed.