Research On Miniaturized, Low-noise, High-gain Optical Amplifier Technology

In recent years,with the development of new data services such as big data,Internet of Things,Cloud Computing,Video Conferencing,etc.People have put forward higher requirements for communication bandwidth,and optical communication has become an effective means to solve high-speed and large-capacity transmission.In optical communication systems,the loss of optical signals is unavoidable,which greatly limits the development of ultra-long-haul optical communications.In order to enable the optical signal to be transmitted over long distances the purpose is achieved by placing an EDFA(Erbium-doped fiber amplifier)on the link.As an important part of the optical communication system,EDFA is mainly used to amplify the signal light in the 1550 nm band,which solves the problem that the optical signal is difficult to transmit over long distances.In order to ensure the transmission performance of the entire optical communication system.It's necessary to study low noise and high gain optical amplification technology to first ensure high quality processing of weak optical signals.At the same time,in order to reduce the size,weight and power consumption of the optical communication device,the internal optical device and the EDFA module need to be miniaturized and easily integrated.This thesis focuses on miniaturized low-noise and high-gain optical amplification technology,and has carried out theoretical research,simulation analysis and experimental research on broadband ASE(Amplifier spontaneous emission noise)noise suppression,two-stage high-gain amplification,low-loss narrow-band filtering,and small-scale package integration design.The main research contents of the thesis include:Firstly,the development of optical fiber communication and erbium-doped fiber amplifiers,the status quo at home and abroad,etc.are summarized.The functions and significance of different kinds of erbium-doped fiber amplifiers are introduced,and the low-noise and high-gain optical amplification technology is described.The important role of long-distance optical communication systems.Secondly,Conducted theoretical research on miniaturization of low noise and high gain optical amplification.The basic structure and working principle of erbium-doped fiber amplifier are introduced.The basic model theory of typical erbium-doped fiber amplifier is studied theoretically.Including the optical wave propagation equation during optical amplification.Finally,the main performance of erbium-doped fiber amplifier is studied.Factors affecting Parameter Gain,Noise Figure,Output Optical Power,etc.Thirdly,A small-scale low-noise and high-gain optical amplification simulation study was carried out.A single-stage,bipolar low-noise,high-gain amplification structure is designed,especially in the two-stage amplification scheme with forward and backward ASE noise suppression design.In this paper,the single-stage amplification and two-stage amplification structure of erbium-doped fiber amplifiers are simulated by the professional optical simulation software OptiSystem.By studying the effects of pump optical power,signal optical power,and erbium-doped fiber length on the performance of the amplification system.Single-stage amplification can not achieve low noise and high gain output at the same time,and dual-stage amplification can achieve high gain and low noise amplification through a specially designed noise suppression structure.After noise suppression,a simulation results that gain of 52.60dB and noise figure of 3.80dB are obtained..Finally,An experimental study on miniaturization of low noise and high gain optical amplification was carried out.This article uses small-scale high-performance optics to build a small,low-noise,high-gain optical amplification system to reduce the size.Experimental studies of single-stage amplification and two-stage amplification structures have been carried out separately.In single-stage amplification,the noise figure and gain cannot meet the requirements at the same time.In the two-stage amplification,a low noise high gain amplification effect with a noise figure of 3.54 dB and a gain of 43 dB is achieved by the effect of wideband ASE noise suppression.In the experiment,the influence of core factors such as 980nm pump power and erbium-doped fiber length on the amplification system is fully studied,and the optimal parameter setting of the system is explored.Finally,all miniaturized optical devices and circuits are miniaturized and packaged to obtain a miniaturized low-noise and high-gain erbium-doped fiber amplifier with a volume of 90×70×15mm,which has the potential to be applied to small optical communication systems.