Research On Key Technologies Of Passive Positioning Sonar Receiving And Acquisition System For Eextendable Wing Underwater Vehicle

Passive positioning sonar is an important means of searching for black box acoustic beacons.With the help of passive positioning sonar carried on the extendable wing submersible platform,it can reach the seabed and search for black box targets in specific areas according to the predetermined planning path,thus providing technical support for the rescue and salvage of the crashed aircraft.Based on the research needs of the sub project "Embedded underwater sensing and sensitive target search technology" of the national key research and development plan "New concept submarine target search submersible with extendable hull",this paper mainly focuses on the design and implementation of the receiving and acquisition system in the project,focusing on the passive positioning sonar for the extendable wing submersible platform.The main research contents include the following aspects.1.Based on the research background,briefly describe the background,principle and importance of underwater passive positioning sonar carried by submarine.According to the actual needs of the black box search submersible,this paper analyzes the adaptive performance of the acoustic sensors carried on the extendable wing submersible.The basic principle,signal conditioning,data acquisition and other key technologies and hardware architecture of passive positioning sonar closely related to the research work are introduced to provide reference for specific unit module design.2.Analyze the characteristics of the passive received signal and the underwater background noise distribution,and research and realize the passive positioning signal receiving and conditioning technology.Research and analyze the technical indicators of signal receiving and conditioning,describe the connection between the receiving sensor and the multi-channel receiver through the analysis of functional module composition,and focus on the low noise technology research on the noise suppression and elimination of the receiver.At the same time,impedance matching circuit,signal gain circuit,filter conditioning circuit and other specific signal conditioning modules are designed and implemented..3.Based on passive positioning signal receiving and conditioning technology,research and implement multi-channel parallel signal A/D conversion technology.According to the signal frequency range,the number of parallel channels,data conversion interfaces and other necessary parameters,the multi-channel parallel signal A/D conversion unit is designed and implemented,including DSP and FPGA interface circuit,parallel acquisition and transmission logic,data preprocessing logic,etc.The principle and logic of signal acquisition,transmission and control are simulated to verify the logic correctness and technical feasibility.4.Complete the test and verification of passive positioning signal receiving and conditioning technology and multi-channel parallel signal A/D conversion technology.It mainly studies and analyzes the function test and performance optimization,pool joint commissioning and function verification,outfield lake test and performance verification,and verifies the key technologies in this research through three progressive stages of test experiments.It also points out the possible problems and provides a reference for further research of the extendable wing underwater vehicle.