The Research Of Beamforming Technique In Low Radiated Noise Submarine Measurement

The sound wave is current in underwater the only energy form that can spread long distance, therefore every kind of underwater equipments adopt the various decline noise technique, and these decline noise technique get great development with each passing day. This put forward higher request for noise measure system in underwater. If the noise measure system cannot scale the low noise equipment noise, this will affect the assess work of noise level of the underwater equipment and affect the further improvement of technique of decline underwater equipment noise. So the research and realization of low radiated noise submarine measurement system is inevitable. The thesis is just about how to measure the noise level of low radiated noise submarine signal using linear array beamforming method. Concrete work is as follows:The paper introduce the method of modify Taylor weighing in application to beamforming. It can attain the most narrow mainlobe width on condition that fjxed sidelobe height, and it attain the lowest sidelobe in terms of fixed mainlobe width and succeed in solving the shortcoming of the traditional Dolph-chebyshev method that is easiest to change in the end power of array signal processing. The theory derivation and analysis is provided in this paper for the near field focus beamforming technology and beam width invariant beamforming technology, and the two technique is used for measuring submarine equipment noise. All of them is simulated in the laboratory and the emulational conclusion is according with the expectation. Base on this , the collection data of 19 sensors array in the sea test is processed using the above method, and data processing result is satisfied .We can draw a conclusion that the application of modify taylor weighting beamforming, near field focus beamforming and beam width invariant beamforming to low radiated noise submarine measurement is very accurate.