Research On Sonar Pulse Detection And Hardware System Realization

Passive ranging is one of the difficulties in the field of underwater sound signal processing. Detecting sonar pulse transmitted by active sonar, it is called "sonar pulse detection" . The main task of it is to measure the working parameter of active sonar and track the target. The key technology is passive ranging, while the key of ranging is the high precise time delay estimation.The research work of the dissertation includes the following two parts: researching the passive ranging technology and developing system hardware of the sonar pulse detection module.The main work of the first part includes: introducing some methods of underwater sound positioning and analyzing their performance, analyzing the theory of measuring direction and distance of the target by three elements symmetrical and dissymmetrical array, comparing the measuring error of two kinds of array, and giving the theory of the generic arrays and discussing the phase wrapping and the distance wrapping in passive ranging.The main work of the second part includes: analyzing the task and the requirements of the sonar pulse detection module, and presenting the idea of the designing the sonar pulse detection module. We construct the dependent subsystem by using digital signal processors as the core and using field programmable gate arrays as control logic and using external memory and analog-to-digital converter as the peripheral.An experiment on the module is carried out with the target simulator ATANC, and the experiment results show that the performance of sonar pulse detection module is good enough.