According to technique of image pre-processing and feedback control and radiatedcharacteristic of furnace, the model, working waveband and parameters of CCD is settled.
The places of resonance points can be adjusted, and the radiatedcharacteristic of transducer with single matching layers was improved by choosing the length of matching layer reasonably.
First, the generation mechanism, components and frequency characteristic of radiated noise of naval ships are studied. There exists periodical modulation for the amplitude of propeller noise.