Electro-optical Logic Gate Based On Dual-drive Mach-zehnder Modulator And Its Application

In recent years,optical logic gates have received a lot of attention for their importance in optical networks.In order to adapt to the transmission characteristics of an electro-optical network,an electro-optical logic gate which can modulate and integrate input signals in the optical domain is proposed.It is simple in structure,easy to integrate and has high performance,and has great research value in the practical network.This thesis explores the realization and application of electro-optical logic gate based on modulator,the main findings are as follows:(1)Combining six basic electro-optical logic gates and NOT gates based on dual drive MZM,24 reconstructed electro-optical logic gates are realized,and corresponding configuration parameters and vector diagrams are given.Simulations were performed at a rate of 10Gbit/s and 24 logic gates were successfully implemented with a set of devices.This thesis introduces the reasons of competitive risk in logical output signal,and analyzes the burr size and location.Taking XOR Gate as an example,the factors affecting the extinction ratio of XOR logical signals were discussed,and the burrs were optimized from these factors.By using filter elimination method,reasonable frequency parameters are set to realize burr elimination.(2)The application of electro-optical logic gate based on dual drive Mach-Zehnder modulator in physical layer secure communication system is discussed.A physical layer encryption modulation integration system based on dual-drive Mach-Zehnder modulator is designed and tested at a rate of 32 Gbit/s.At the rate of 10 Gbit/s,a simulation system was built:the traditional OOK signal transmission system,the physical layer encrypted modulation integrated transmitter transmission system based on dual-drive Mach-Zehnder modulator,and the system’s encryption performance was analyzed at 0 to 50 km optical fiber transmission distances.Compared with the OOK signal,the extinction ratio of the encrypted signal was significantly higher than 5 dB after different transmission distances.(3)Using I/Q modulator as the main device,the design and development of high-speed photophysical layer decoding prototype were carried out from optical circuit module,circuit module and chassis module respectively.The prototype was functionally tested in 1 Gbit/s experimental system to verify the realization of encryption and decryption functions.The performance of the prototypes was also tested at different rates with an extinction ratio of 12.5 dB at 10 Gbit/s.