Research Of Dynamic Characteristics For The Radio Over Fiber System And The System’s Optimization Design

Radio over Fiber is a new kind technology that combines light wave and microwave. It integrates the advantages of optical fiber communication in low power, wide bandwidth, high immunity to electro-magnetic interferences with that of wireless communication in wide coverage, flexible access and so on, making it one of the most promising communication technologies in both academic and commercial fields during the recent several years. And it is also thought to be with great research and application prospects in the near future. The Distributed Antenna System based on Radio over Fiber can be viewed as a kind of cognitive network on one hand, to realize wide-range information collection. On the other hand, it adjusts to the development of Mobile Internet and provides an "anytime, anywhere, anything" access service to meet the consumers’demand for quickly approach the net.This thesis focuses on the key indicator "Dynamic Range", and is devoted to the theoretical research and experimental verification for the dynamic characteristics of Radio over Fiber system. It consists of four parts. The first part analyzes the upper limit of the system’s dynamic range and researches two main factors that affect it. Then an experiment is made to observe how they restrict the system’s dynamic character. The second part is mainly about the discussion of the lower limit of the system’s dynamic range, including the formula derivation for the system noises, the study for the effect of optical losses on the system transmission and the comprehension for the concept of it. The third part is based on the analysis of upper and lower limits of the system’s dynamic range, the distortion and the optical losses to realize the system’s optimization design, aiming to make the system operate with a lower cost, which is of great significance in the build of practical Radio over Fiber network. The last part is about an actual Distributed Antenna System that I built based on Radio over Fiber technology, including the state sensing, the video monitoring and the broadband access. It is a small model of the modern Internet of Things.