Design Of Towed Sound Source System For Ship Radiating Noise Simulation

The underwater sound source system is widely used in marine scientific research,underwater acoustic countermeasure technology,underwater target detection and other fields.This paper mainly designs a towed sound source system for the purpose of simulating the radiated noise of ships.The towed sound source system integrates the electronic system and the battery system into an electronic cabin,without using an external cable,the signal can be transmitted according to the predetermined configuration after entering the water,and the transmitting transducer and the electronic cabin are installed and fixed to the guide tow body,which is convenient for It is hoisted at sea for towing.By analyzing the spectral structure and sound source level of ship radiated noise,combined with the current ship acoustic stealth technology,the low-frequency noise of the quiet ship target is simulated in a targeted manner.CW pulse,LFM pulse and continuous sinusoidal signal functions commonly used in acoustic research.This paper uses ARM+FPGA as the architecture to realize the control of the overall system,and drives the high-speed DA as the signal source to output the analog signal.The power amplifies the output signal of the signal source through the class AB power amplifier circuit,and drives the transmitting transducer to transmit the acoustic signal underwater.The lithium battery pack is used to power the system,and the standby duty function and power management system are designed to improve system efficiency and meet long-term power supply needs.The digital chip cooperates with the peripheral circuit to detect the voltage,current and temperature during the working process,and design the protection circuit through a reasonable heat dissipation structure and solid-state relay to deal with the circuit safety problems caused by high current,high voltage and heat during the working process of the power amplifier circuit.The digital frequency synthesis technology is adopted by the digitally controlled oscillator(NCO)to generate CW pulses and LFM pulses;based on the "ping-pong operation",the dual RAM is turned on to realize seamless buffering and processing of ship radiated noise files from TF card reading to DA output..Program development is carried out for the signal control module and protection module of the hardware system,and the error correction of the real-time current value is performed to realize high-precision current detection.From the perspective of engineering practicability,the control software of the host computer is developed based on VC++,which has user-friendly functions such as flexibly configuring the signal parameters of the sound source system,power-on mode and enabling fixed-depth emission.Finally,the thesis tests various modules,transmitting functions,power consumption and other aspects of the system to ensure that all functions of the sound source system are used normally and reliably,and reach the predetermined technical indicators.The research in this paper lays a technical foundation for the design of low-frequency highpower self-capacity sound source system,which can be realized by replacing high-power power supply modules and parallel power amplifier chips on the basis of this paper.