The Study Of Through-Signature About Underwater Target Based On Focused Beam-Forming

The purpose of this paper is to measure the through signature of noise source going through hydrophone or hydrophone array laying on the sea bed. That is noise source level measurement of ship through signature. It gives basis for judging the ship work or not, and differentiating other ships go through or not, so as to achieve the purpose of detecting the port.Noise source level measurement of the ship through signature is different with ship noise source level standard measurement. That is to say, it need not get the true value about ship noise source in the measurement of through signature. It is important to choose the right measurement elements to ensure the repeatability and comparability of the results.First of all, through signature of single hydrophone is studied. Secondly, key elements affecting through signature of single hydrophone are analyzed. It establishes the maritime pilot program about measuring the correction factor of dome directivity. Finally, it puts forward through signature method based on focused beaming-forming for shortcoming that single hydrophone can not inhibit mlti-path effects.The analysis of measured data shows that, for strong interference signals, the through signature method based on focused beaming-forming can effectively reduce the noise and increase gain. For weak interference signals, the through signature method based on focused beaming-forming can increase the gain.