Study Of Triangular Shaped Optical Pulse Generator Based On DD-MZM

ABSTRACT:Microwave photonic technology is a new technology that combines optical fiber communication and wireless communications, and it has been widely used in civilian communications, military and defense, aerospace, automotive communications and bio-medical fields nowadays. Millimeter-wave generator is one of the hot spots of microwave photonic technology.Since there are only odd harmonics exist in triangular optical pulse spectrum, and it has advantages such as slope linearization in waveform etc. It has been widely used in optical wireless communication systems (ROF).This paper presents a triangular optical pulse generator scheme based on microwave photons technology, using optical carrier suppression technology and fiber dispersion effect of Mach-Zehnder modulator (MZM), ultimately obtain triangular optical pulse with high repetition rate by adjusting the continuous optical pulse emitted from continuous wave laser. The main contents are as follows:Using the DD-MZM as a basic element, we study the basic principles and characteristics of the MZM chirp, analyze three modulation methods of MZM, then we summarize the advantages of suppressed carrier modulation scheme, control the parameters of MZM device strictly, then we obtain an output optical signal expression which infinite approach triangular pulse Fourier transform formula through theoretical analysis and formula derivation. And we use optical simulation software optisystem to prove the system of the scheme according to the quantitative expression analysis.Analyze the basic principle of the fading and broadening that result from dispersion, propose several common dispersion compensation technology, further analyze the proposed triangle millimeter wave generation system principle, then we get the optimum dispersion amount required to produce triangular optical pulse, and we eventually obtain triangular optical pulse through dispersion compensation technology with strict control of dispersion amount in the system which has been proved by optisystem simulation.Through theoretical analysis and simulation, we prove the feasibility and advantages of the demonstrated triangular optical pulse generation based on DD-MZM. This triangular wave generation scheme has advantages of high repeat ability, continuous tunability etc. which has provided foundation for the later-building of this system platform scheme and provided a reference to resolve related issues for the further practicality.