The energy ratio of broadband signal is utilized for port/starboard discrimination in towed line array with hydrophone triplets in tradition. It works well in most conditions except for two cases： One is low signal t...The energy ratio of broadband signal is utilized for port/starboard discrimination in towed line array with hydrophone triplets in tradition. It works well in most conditions except for two cases： One is low signal to noise ratio（SNR）, and the other is that there is a stronger interference lied on the other side of the line array with approximate bearing angles. A method called line-spectrum character extracting is proposed to discriminate port/starboard for these two cases in this paper, and the SNR needed for port/starboard discrimination is reduced significantly. Simulation and the sea-trial data are analyzed to show that the method is stable and valid, and is expected to be applied in real towed line array sonar. A line-spectrum enhancing technology with lower calculation complexity and stable validity is proposed to ensure the application of this method in lower SNR condition.展开更多
There are highly intensive and stable line-spectrums in the radiated noise of passive target,and different targets have line-spectrums with different frequencies.This paper puts forward Conventional BeamForming（CBF）...There are highly intensive and stable line-spectrums in the radiated noise of passive target,and different targets have line-spectrums with different frequencies.This paper puts forward Conventional BeamForming（CBF） variance-of-frequency detector,which weights bearing spectrum using the variance of frequency of line spectrum with maximum amplitude in each azimuth. It is able to suppress multi-target interferences effectively,and detect faint signal in the background of strong interferences.What＇s more,CBF variance-of-frequency detector needs only three-dimension display,while other line-spectrum detectors require for four-dimension display.The simulation and trial data analysis show that the CBF variance-of-frequency detector is able to detect faint line-spectrum target in the background of the continuous spectrum strong interferences.展开更多
文摘The energy ratio of broadband signal is utilized for port/starboard discrimination in towed line array with hydrophone triplets in tradition. It works well in most conditions except for two cases： One is low signal to noise ratio（SNR）, and the other is that there is a stronger interference lied on the other side of the line array with approximate bearing angles. A method called line-spectrum character extracting is proposed to discriminate port/starboard for these two cases in this paper, and the SNR needed for port/starboard discrimination is reduced significantly. Simulation and the sea-trial data are analyzed to show that the method is stable and valid, and is expected to be applied in real towed line array sonar. A line-spectrum enhancing technology with lower calculation complexity and stable validity is proposed to ensure the application of this method in lower SNR condition.
文摘There are highly intensive and stable line-spectrums in the radiated noise of passive target,and different targets have line-spectrums with different frequencies.This paper puts forward Conventional BeamForming（CBF） variance-of-frequency detector,which weights bearing spectrum using the variance of frequency of line spectrum with maximum amplitude in each azimuth. It is able to suppress multi-target interferences effectively,and detect faint signal in the background of strong interferences.What＇s more,CBF variance-of-frequency detector needs only three-dimension display,while other line-spectrum detectors require for four-dimension display.The simulation and trial data analysis show that the CBF variance-of-frequency detector is able to detect faint line-spectrum target in the background of the continuous spectrum strong interferences.
