The Study Of Maritime Wireless Transmission Based On SC-FDE

Based on the single carrier frequency domain equalization (SC-FDE), maritime wireless transmission technology is researched in the paper. At present, the study of maritime wireless transmission is restricted due to the broad surface, no fixed base stations and not mature maritime wireless channel model. The paper aims to provide practical technology and technical basis for maritime wireless transmission system. In this paper, maritime wireless channel model analysis and other work are as follows.Firstly, the paper considers the effects of the direct, specular and diffuse reflections in maritime radio wave propagation, the energy of the specular reflection and diffuse reflection are analyzed in theory and the maritime multi-path channel model is established. The maritime wireless transmission is divided into two categories:one is from ship to shore communication and the other is ship to ship communication. Carrier frequency, transmission distance and antenna height on the impact of multi-path channel are discussed in both cases, respectively.Secondly, the frame structure of SC-FDE system is designed, the peak average power ratio and performance of SC-FDE are compared with orthogonal frequency divisioh multiplexing (OFDM), and the transmission performance of SC-FDE is studied under maritime multi-path channel. The simulation results show that SC-FDE system has a good system performance under maritime multi-path channel. With the increase of transmission distance, the symbol error rate of SC-FDE system increases, but it decreases with the increase of the guard interval length, and when the guard interval length is constant value and unique word length in the frame structure decreases, the symbol error rate of SC-FDE system also reduce.Finally, based on the traditional synchronization algorithm of the SC-FDE system three new timing metric calculation methods are proposed by changing training sequence structure. The simulation results show that improved synchronization algorithm is helpful in avoiding the phenomenon of the timing metric plateau, suppress redundant peaks and reduce the mean square error of the timing offset.