Studies On EDFA And Ultra-short Pulse

As is known to us all, the optical fiber communication has become more and more popular in our modern life. The optical fiber amplifiers and ultrashort pulse source are key devices in the system. The dissertation is focused on EDFA and pulse compression used for narrower pulsewidth. And the main contents are as follows.I. Experimental research was done on C-band and L-band EDFAs which are composed of high-concentration-Erbium-doped fiber. Two EDFAs are made with different EDFs in length, using the 980nm LD as the pump source. The gain spectra, Gain, NF, saturation input and output power etc. are measured respectively. In addition, the shape of the gain spectra which can optimize the L-band EDFA are brought forward.II. Pulse compressions were theoretically and experimentally analyzed. Including,1) Hyperbolic secant pulse of 1550nm in wavelength, 12.5ps in pulsewidth and 3mW in peak power was well compressed.2) Pulse was compressed by comb-like dispersion profiled fiber. Pulse of 6.25ps in pulsewidth, 3.1 compression ratio was compressed with a little pedestal component.3) Fundamental soliton was compressed by d-EDFA, different compression ratio were gained with fibers of different GVD.4) Loss management fiber was used to gain a good compression.III. Based on the analyses of generation mechanism of CS-RZ, 20GHz optical pulse of CS-RZ was generated by using 10GHz MZI-LN-MOD which worked at zero bias. Meanwhile compared to the frequency spectrum of RZ, its characteristic in suppressing the carried wave was fully confirmed. Besides, we simulated the transmission of CS-RZ and RZ in fibers, and the CS-RZ format with better nonlinearity tolerance was shown to be a better choice for high bitrate and long haul optical fiber transmission.