Study On 1550nm Amplifier Based On Double-clad Fiber And High-power Detector

Fiber amplifiers with high-power, wide-gain band and low-noise figure are required for applications to DWDM systems, fiber CATV system and space optical communication system. Ultrahigh-power, ultra-wide band and optimal parameters are becoming the goals the fiber amplifier pursues for and the focus both at home and abroad. Based on the characteristics of double-cladding fiber's configuration, the amplifier with high-power output at 1550 nm is studied in this dissertation by using the cladding-pumped coupling technique.In this dissertation, the double cladding Er³⁺-Yb³⁺ co-doped fiber amplifiers is designed and optimized through theoretical analysis at first. Using the Runge-Kutta method to solve the rate and power propagation equations of amplifiers, the output signal power, gain and noise characteristics of double cladding Er³⁺-Yb³⁺ co-doped fiber amplifiers pumped at 975nm are investigated numerically. Their varyings as functions of the active fiber length, input pump power and input signal power are described.The experiment measured the major functional parameters of the amplifier. When the pumping wavelength was 975nm and the total pumping power was 10W, the output power of the amplifier at 1550nm reached 400mW with Ps=0dBm and the small-signal gain was more than 26dB.With the development of fiber communication technology, fiber measure equipment is also in progress, which is obviously important to the measurement of transferring laser. Optical detectors are important fundamental equipments in many fiber system measure instruments that need empolder urgently.In this dissertation, all kinds of familiar optical detectors on the market are introduced classifiedly. The principle of the pyroelectricity optical detector is analyzed emphatically. A high-power fiber-chucking device is designed. A kind of high-power pyroelectricity optical detector is studied through experimentation, and its characteristic is assessed and compared.