Underwater Acoustic Decoy On Acoustic Homing Torpedo Interference Mechanism And Simulation Studies

As a common means to defense acoustic homing torpedo, soft-kill devices are drawing more and more attention. The study on acoustic interference shrapnel is a new topic which was put forward in this application background. It relies on the noise generated by underwater explosion of ammunition to reduce the sonar receiver SNR to achieve the purpose of improving the probability of ship survival. Compared with the traditional noise-jammer, acoustic interference shrapnel has the characteristics of high energy conversion, high Source Level, wide bandwidth and low cost, so this study has a very broad application prospects.In order to make acoustic interference shrapnel exploded underwater by a certain sequence to form a stable interference source, the circuit which control underwater detonation was designed. The circuit model use a microcontroller as the master chip, has well precise delay, and the tests of underwater detonation verify the accuracy and reliability of the circuit.In this paper, the average reduced rate of torpedo homing detect distance is used as the evaluation indicator of acoustic countermeasure (ACM) effect, and establish corresponding mathematical model. Aiming at three factors that impact ACM effect, simulation on it has been carried out by using Monte-Carlo simulation method. The results show that underwater detonation of acoustic interference shrapnel can play an important role in interfering with active homing torpedo, especially in the case of good sea state and large depth.A mathematical model for anti-torpedo decision of vessel is presented in this paper, and mathematics optimization methods are used to resolve the model into nonlinear constraint target optimization function. The optimal evasion angle and the perfect location of acoustic interference shrapnel in different attacking states of torpedo are obtained by simulation. The results show that the perfect launch angle of acoustic interference shrapnel almost has nothing to do with the attacking state of torpedo, and always has two perfect locations. These results can be well guided the use of acoustic interference shrapnel in actual combat.