Research On Pulse Signal Detection Technology With Unknown Parameters In Target Simulator

With the competition for ocean resources and the rapid development of intelligent acoustic equipment world widely,the target simulator which can be used in training scenarios has become a hotspot in the development of underwater acoustic equipment nowadays.Due to the high human and economic costs in underwater weapon training tests,simulating the real target echo by transmitting the received pulse signal from the target simulator can improve the efficiency of scientific research,reduce the cost and increase the number of experiments.So,the detection performance of the target simulator is particularly important.Taking the detection of unknown parameter pulse signal in the target simulator as the background,this paper discusses the noise power spectrum estimation,signal enhancement based on short-time spectrum amplitude estimation and the detection of unknown parameter multipath pulse signal.Firstly,according to the requirements of signal enhancement algorithm on short-time spectrum amplitude estimation for noise statistical characteristics estimation,minimum statistics algorithm,continuous spectrum minimum statistics algorithm,minimum-contraled recursive averaging noise estimation algorithm are discussed,this paper realizes the continuous tracking of the statistical characteristics of noise even in the presence of a signal,analyzes the influence factors,advantages and disadvantages of the three algorithms,and uses the ocean exprimental data to verify the tracking optimality of minimum-contraled recursive averaging noise estimation algorithm.Secondly,the enhancement algorithms of unknown parameter pulse signal based on shorttime spectrum amplitude estimation were discussed,such as spectrum subtraction,improved spectrum subtraction,minimum mean square error amplitude estimation and minimum mean square error logarithmic amplitude estimation,this paper analyzes the enhanced performance of the minimum mean square error logarithm amplitude spectrum estimation.The data of ocean experiment were used for processing and analysis,the results shows that the algorithm enhances the signal effectively,improves the signal-to-noise ratio,makes a good foundation for the detection of unknown parameter pulse signal.Finally,under the influence of multiple paths,two pulse signal detection algorithms with unknown parameters are studied,sliding window energy method and Page Test method are studied.Through the double verification of simulation and data,the Page Test algorithm can respond to the transient moment of the signal more quickly.In addition,the ocean experiment data are used to verify the algorithm combining the Page Test algorithm and the minimum mean square error logarithm amplitude spectrum estimation algorithm.The results show that this algorithm effectively improved the detection performance of the system.