The Research And Design Of OFDM-ROF System

With the coming of the 5G era,5G will go into all aspects of life to meet the diverse needs of people.5G technology has been researched,and OFDM-ROF technology fully combines the advantages of wireless communication technology and optical fiber communication technology.OFDM-ROF technology has the advantages of high capacity,low loss,anti-interference and so on.OFDM-ROF technology was one of the key technologies for 5G research,which has attracted the attention of scholars in the world.FPGA,with strong parallel processing ability and real-time performance,has been a very effective choice for real-time digital signal.With high integra-tion and flexibility of the AD9361,the RF design of the transmitter is significantly simplified.Based on FPGA,using the AD9361,an OFDM-ROF transmitter has been proposed in order to generate the real-time OFDM signal.The influence of fiber dispersion on signal transmission in OFDM-ROF system has been studied,and the optical fiber dispersion compensation scheme has been proposed in this paper.The main contents and results of this research are as follows:1.The research background,research status,technical principles of OFDM-ROF technology are simply introduced,and three transmission schemes in ROF system are described and compared.2.Based on the principle of OFDM-ROF technology and the RF transmission scheme of RF signal in ROF system,the OFDM-ROF transmitter has been built to real-time generate 2.4GHz OFDM radio frequency signals.The OFDM baseband modulation was divided into several modules by the top-down design method and realized on FPGA.By configuring the AD9361 related register,the digital baseband signal was modulated the 2.4GHz RF signal.The test results of the transmitter show that the transmitter has good performance,and it can meet the requirements of real-time OFDM-ROF signal transmission.3.By means of OFDM-ROF technology,Opti System and MATLAB software are used to build the simulation platform of analog OFDM-ROF and digital OFDM-ROF communication system.The signal transmission performance of the two systems have been analyzed and compared from the experimental results.The digital OFDM-ROF is superior to analog OFDM-ROF in transmission performance,with more stable dynamic transmission distance.The simulation results show that the intra-symbol frequency domain average method and dispersion compensation can improve the transmission performance of the system.