Passive sonar device, directional concentration processing method, and passive sonar signal processing program

摘要

PROBLEM TO BE SOLVED: To improve visibility of a narrow-band signal by removing a broad-band signal without affecting the narrow-band signal.SOLUTION: A passive sonar signal processing program includes: a signal processing step of subjecting a reception signal to Fourier transformation and then normalization to output the resulting signal as a normalized signal, and also calculating the azimuth of a sound source from the reception signal to output the azimuth as an azimuth signal; an azimuth concentration step of calculating an azimuth density distribution of the sound source on the basis of the azimuth signal, sharpening the azimuth from the azimuth density distribution, and outputting the azimuth as a sharpened signal; a broad azimuth removing step of subtracting the sharpened signal from the normalized signal and outputting the result as a broad removal signal; and a display processing step of displaying an image on the basis of the broad removal signal.