Research Of Model-Based Singnal Processing On Underwater Acoustic Localization Method

In recent years,with the introduction of the national ocean policy,accelerating the construction of a maritime power has become a need for domestic development.Acoustic localization technology has also become one of the hot spots in the field of underwater acoustic.However,how to detect,locate,and track the target in a complicated and ever-changing shallow sea environment and improve the positioning accuracy and signal processing performance are still the difficulties of the underwater acoustic localization technology.Traditional positioning methods such as ternary array positioning system can not estimate the depth of the sound source,the positioning of long-distance sound velocity gradient will also cause greater error.With the development of matching field processing(MFP),matching field passive positioning technology has been favored by many scholars and experts.When the ocean channel model approximates the real marine environment,the matching field processing has more accurate positioning results and can well estimate the sound source distance and depth,also have good results in terms of noise suppression and processing gain.However,the matching field processing uses a deterministic environment model.The complexity of the real ocean channel causes mismatch problems such as mismatch of environment in the matching field processing,and the applicability is limited.In order to solve the problem of matching field mismatch sensitivity and provide a more robust positioning method,this paper has carried out a research on underwater acoustic localization based on model-based signal processing in shallow sea environment.The environment model,noise model,propagation model and other physical models and signal processing knowledge are combined to provide an adaptive positioning method.Compared with the traditional signal processing technology,it has a more distinct performance advantage,and has a more promising application prospect in engineering applications.In this paper,based on the theory of model-based technology,the localization system of sound source in water is established by using the acoustic wave propagation model of simple wave.The formulas of sequential Bayesian technology and particle filter are studied.The state model and measurement model are established.And the objective function is constructed.On the basis of this,the localization and simulation of underwater target is carried out.The simulation results converge,and the error with the real value is small,which can locate the target's distance and depth more accurately.In order to further verify the reliability of the method and the validity of the location,a 32-element hydrophone vertical linear receiving array(VLA)was used to locate the source of the explosion and to further process the experimental data at sea.The results were compared,and performance has been verified.Error,influence factor analysis and performance advantage of water target location has been analyed,which laid the foundation for the practical application of the signal-based signal localization.