Research And Validation Of Key Technology For 100Mbps Wireless Transmission In Sea Surface Environment

With the improvement of national strength,the strategic position of the sea becomes more and more important,and the demand for coordinated situational awareness and realtime information transmission of the marine combat fleet becomes more and more urgent,and a sea surface high-speed wireless communication system is urgently needed to provide technical support for high-speed and reliable communication between sea surface communication nodes.Due to the complex and variable ocean channel environment and strong reflection path,the current sea surface high-speed transmission technology cannot meet the needs of the sea surface fleet for long distance,high speed and low cost.In this paper,based on a full study of the sea surface wireless communication channel,and drawing on mature technologies of wireless transmission at home and abroad,a sea surface communication waveform with a transmission rate of one hundred Mbps is designed to achieve high-speed and reliable data transmission in the sea surface environment,and the main research contents of this paper include:First,the current status of research on sea surface communication is summarized and analyzed.According to the characteristics of sea surface communication channel,the multi-carrier system based on orthogonal frequency division multiplexing technology is selected to design sea surface high speed transmission waveform according to the application requirements.The key parameters involved in the sea surface propagation environment,such as electromagnetic wave transmission path attenuation,multipath effect and Doppler effect,are theoretically analyzed,and the functional indexes of the designed waveform are analyzed,and the key performance indexes are thoroughly demonstrated.Second,based on the sea surface wireless channel characteristics and functional performance index requirements,a multi-carrier communication link with 100 Mbps wireless transmission in the sea surface environment is designed.Firstly,a waveform design scheme for sea surface high-speed wireless transmission is given,including bitlevel information processing,symbol-level signal processing,and digital intermediate frequency signal processing.The design process of signal processing algorithms of key modules such as scrambling and descrambling of baseband signals,channel coding and decoding,orthogonal frequency division multiplexing(OFDM)modulation and demodulation,time synchronization,frequency correction,and digital variable sampling rate is analyzed in detail.Matrix laboratory(MATLAB)software is used to carry out floating-point simulation of the communication link designed in this paper to verify the designed transmission waveform and key technologies,including the simulation test of time-frequency synchronization,channel equalization,bit error ratio(BER)and other indicators.Finally,the hardware implementation and verification of the high-speed wireless communication system designed in this paper on field programmable gate array(FPGA)platform are completed.The overall architecture and resource distribution of the hardware implementation platform are outlined,and the implementation framework of the sea surface wireless communication system is given.The implementation scheme of the key modules such as time-frequency synchronization and channel equalization of the sea surface high-speed wireless communication system is analyzed in detail.Finally,the BER,packet loss rate and other indexes of the communication system are tested in the experimental and microwave darkroom.The test results verify the function and performance indexes of the communication system and prove the feasibility and reliability of the designed communication system.The sea surface high-speed wireless communication system designed in this paper improves the communication capability between sea surface ships and provides theoretical reference and engineering support for future maritime communication.