Power Over Fiber Technology And Its Applications In Communication And Detection

Power over fiber technology is a new energy supply technology that uses special optical fiber to transmit high-power laser to the remote end,and then the electrical energy converted by photovoltaic cells is used to power the device or module.Due to the inherent advantages of optical fiber such as small size,low cost,and electromagnetic isolation,power over fiber technology has important applications in the fields of sensing,monitoring and communication,especially in special scenarios such as flammability and explosion,strong electromagnetic interference,and strong radiation.Starting from the background and significance of the topic,this thesis introduces the advantages of power over fiber technology and the research progress at home and abroad,and explains the main application areas of power over fiber technology;then it discusses the key components of the power over fiber system.The basic principles of power lasers,high-power energy-transfer fibers and photovoltaic cells have been studied,and the performance parameters of these key devices have been analyzed.Then,an power over fber scheme was designed.The program consists of high-power lasers,energy-transmitting fibers,photovoltaic cells and DC-DC step-down modules.High-power laser produces a laser with a power of 3W,transmits it through a 2km multimode fiber,converts the laser into current and voltage through a photovoltaic cell,and then converts it into a stable voltage through a DC-DC step-down module.And then,the performance of the scheme was tested experimentally,and finally a 2km optical fiber remote transmission with 165 m W electric power was realized,and the overall energy conversion efficiency was 5.5%.On this basis,a Radio-over-Fiber(RoF)scheme based on power over fiber technology is designed.The key technologies involved in the scheme(such as OFDM technology,OFDM-RoF system and DDO-OFDM structure)are analyzed and researched.An experimental scheme is proposed and the transmission link and digital signal generation process of the scheme are explained in detail.In the verification experiment,realized the2 km distance transmission of 1GHz bandwidth 16QAM-OFDM signal based on power over fiber technology,obtained a clear constellation diagram when the input optical power was-6dBm to-1dBm.Simultaneously,a railway electromagnetic interference detection scheme based on power over fiber technology is designed.Collect the electromagnetic signal along the railway by a directly modulated laser powered by optical fiber(simulated by an arbitrary waveform generator and a vector signal generator).After being transmitted by a 2km single-mode optical fiber,the electrical signal is recovered by a photodetector and the electrical signal is obtained by a vector signal analyzer.Spectrogram,constellation and eye diagram of the signal.The electromagnetic interference detection scheme based on optical fiber energy transmission successfully identified the type of electromagnetic interference suffered by the railway GSM-R signal.