Research For Underwater Acoustic Synchronous Positioning Based On Single-carrier Communication Technology

With the rapid development of ocean industry, people desire to explore the underwater resources, and thus, underwater acoustic communication and positioning technology become one of the very active research areas in recent year. The single-carrier frequency domain equalization technology has also been proven to be a research focus in wireless communications these years, with its its unique characteristics to suppress multipath effect, eliminate inter-symbol interference and overcome Doppler frequency shift. In addition, introduceing the concept of time stamp in underwater acoustic communication, as the the tag number of a data frame, can effectively solve the problem of data frames receiveing in proper order and fuzzy distance. So, the time stamp mechanism being introduced into the data frames of single carrier frequency domain equalization, with the timestamp-based single-carrier underwater wireless communication technology to achieve the underwater positioning purpose, can be a good solution to realize underwater positioning in the complex underwater acoustic channel conditions.Traditional underwater acoustic positioning technology was largely based on acoustic echo signal detection method, and the positioning accuracy depends on the underwater acoustic channel conditions. This paper mainly focuses on underwater positioning with the timestamp-based single-carrier underwater wireless communication technology and the main work and achievements are:(1) The underwater acoustic channel is analyzed, including the main features and concepts, and thus design the corresponding acoustic channel model, and consider the basic principles of single carrier underwater acoustic communication system.(2) The classification of acoustic positioning system and performance are described in detail, and then we propose the acoustic positioning calculation model based on the time-difference and phase-difference calculation methods, and analyze their principles, meanwhile, we start the detailed mathematical statements to study the positioning error and obtain the positioning error equations.(3)The single carrier underwater acoustic communication technology about synchronous positioning is detailedly studied, and then we discuss the feasibility of introducing the single-carrier technology and the time stamp concept to realize precision underwater positioning, give the structure of the positioning system as well as its performance advantages. Our studies show that the single carrier underwater acoustic communication synchronous positioning system can effectively solve the strong multipath interference and fuzzy distance problems in underwater channel, and achieve underwater moving target continuously tracking and positioning. Moreover, we demonstrate the relationship between communication rate and underwater positioning. In a conclusion, utilizing the single-carrier wireless communication technology to carry out underwater target tracking and positioning, has a good theoretical basis and market prospects.(4) Through the pool experiments based on some necessary hardware platforms, observing the underwater acoustic signal transmission results in specific environment, the experiments show that the underwater acoustic channel exists indeed serious multi-path interference and attenuation effect. Besides, with the single carrier frequency domain equalization underwater acoustic communication system, and the underwater acoustic channel model parameters, we implement some Matlab experimental simulations, the results show that the single carrier frequency domain equalization technology effectively overcomes the strong multi-path interference, and achieve a high-quality underwater wireless communication data transmission result. Finally, we also carried out the corresponding real-time underwater moving target continuously tracking and positioning simulations, the experimental data satisfactorily covers our research method and results in this paper.