Study Of The Generation Of Wavelength Tunable Chaotic Laser Based On Ultra-long Erbium-doped Fiber Ring Laser

With the maturity of the fiber manufacturing technology and the improvement of the semiconductor laser technology, fiber laser is now becoming a new research focus in the laser field. The erbium-doped fiber laser is widely used in optical communication system because of the advantages of wide gain spectrum, low loss and high average power, what’s more, the wavelengths locate in the low loss window of optical communication system. In recent years, with the rapid development of DWDM system, the wavelength tunable erbium-doped fiber laser is more and more important. Chaotic lasers are widely used in high-speed chaotic secure communication, anti-interference ranging, and sensing field because of their natural confidentiality, anti-interference, and non-predictability. Fiber lasers generate chaotic bandwidth of at least tens of GHz. The wide bandwidth leads to high-speed data transmission and high precision measurement resolution in the WDM network communication and detection. Moreover, the measurement resolution of the chaotic optical signal is not related to fiber length, therefore, the tunable chaotic laser is a promising light source in the future application of the WDM network.The erbium-doped chaotic fiber laser with the tunable fiber Bragg grating was carried out:1. The characteristics and application of erbium-doped fiber laser is summarized. We make a comprehensive review about the development trend of the chaotic generation and the tunable fiber laser.2. The theoretical model of the chaotic generation of erbium-doped fiber laser is analyzed, and the technological principle of the tunable fiber laser is introduced.3. The tunable chaotic output of erbium-doped fiber ring laser is studied experimentally. The results show that the output of the tunable chaotic laser have the wavelengths with0.5nm linewidth from1533nm to1558nm, and any of the wavelengths is chaotic with10GHz bandwidth at least. The full width at half maximum of the chaotic correlation curve of the different wavelengths is on a picosecond timescale, thereby offering millimeter spatial resolution in WDM detection.4. We carried out an experiment to detect the WDM-PON network to further prove the excellent properties of the tunable chaotic laser, and the spatial resolution from the point of different wavelengths and different distance is analyzed. The experimental results demonstrate the wide bandwidth, the high spatial resolution and signal to noise ratio characteristic of the tunable chaotic laser, what’s more, the experiment come to a conclusion that the spatial resolution has nothing to do with the detected distance.