Research On Adaptive Control Of Underwater Target Echo

In underwater offensive and defensive confrontation,the enemy’s active sonar uses echoes generated by our targets for detection,identification and parameter estimation.In order to improve the stealth performance of our equipment,it is necessary to study the adaptive control mechanism of the underwater target echo and summarize the method of weakening the target echo.Traditional passive stealth technology has limitations and is difficult to adapt to the development trend of high-speed informatization.Active control methods have gradually become research hotspots due to their high flexibility and strong applicability.This paper focuses on the problem of adaptive control of low-frequency active sonar target echo.The parametric array is used to generate low-frequency signals,and the target characteristics are added to simulate the target echo signal,and the simulated echo signal is constantly close to the actual echo through the adaptive control algorithm.In this way,adaptive echo control is achieved.Firstly,this paper studies the mechanism of active sonar echo signal generation,and simulates low-frequency active sonar target echo signals based on the characteristics of simple typical targets such as noise,envelope,doppler frequency shift,and phase jump;Secondly,based on the basic theory of parametric array,actively emit a lowfrequency control signal in the medium,study the modulation algorithm of the parametric array transmission signal,analyze the relationship between the difference frequency wave and the original frequency wave in phase and amplitude,and select the best amplitude and phase conditions in the echo adaptive control process;Thirdly,focus on the study of adaptive control algorithms,make various improvements to the kernel function and adjustment parameters of the nonlinear function variable step size algorithm,analyze the performance differences of the algorithm before and after the improvement according to the simulation results;Finally,integrate the research results of each part to form a set of the whole process of target echo adaptive control.Through the simulation analysis of the factors that affect the target echo active control effect,the appropriate active control signal conditions are obtained,and the echo cancellation different adaptive control is analyzed.The influence of different sonar detection signals under the control algorithm.The research results show that the improvement of the kernel function and adjustment parameters of the adaptive algorithm in this paper has advantages in convergence speed,antinoise performance,tracking performance,calculation amount and steady-state error.The combination of adaptive algorithm and parametric array to generate low-frequency simulated target echo can reduce the echo intensity of the target in the receiving direction of the enemy sonar,and achieve effective suppression of low-frequency active sonar target echo.