Digital Underwater Microphone Design And Application

Compared with other physical acoustic field such as electromagnetic waves,the sound wave hasthe minimum damping coefficient in an aqueous medium,so it become an important carrier ininformation collection and information transmission in the vast sea. Underwater microphone is atransducer which is converted from acoustic signal to electrical signal,have an important role inresearch on underwater complex environment,noise source location and identification, underwatercommunication and navigation,military weapons development and other areas.In the background ofthe noise location and identification of ships, this paper design a dual-channel digital hydrophonebased on STM32F107and study the noise source location and identification method applied to ships.First of all, this paper design a dual-channel digital hydrophone based on STM32F107,describehardware circuit design and software design of the system in detail, propose the signal acquisitionideas which amplify the same analog signal with different multiple and digitizing to ensure accuratesignal acquisition. After debugging and verification, system achieve the main technical indicators:The sampling frequency is80KHz; sampling precision is24bits; bus transfer speeds greater than500kb/s; memory depth of per channel is64Mbit.Secondly, this paper discuss digital hydrophone arraying method. Use adaptive filtering to filterhydrophone signal, introduce the main performance parameters of the array, Signal model for uniformlinear array and uniform circular array is modeled, and comparative and analysis the uniform lineararray and uniform circular array.Finally, this paper analysis characteristics of radiated noise from surface of ship. According tothese characteristics, this paper analysis the characteristics of the location and identification method ofthe ship source noise. Introduces near-field focus noise sources location technology based on auniform linear array, detailing the high-resolution near-field noise source location method. Describetwo corrected location algorithm in detail, and then the simulation demonstrates two correctedlocation algorithm is more applicable to the ship noise.