Passive Acoustic Direction Finding of Ground Target with Small Array Based on Particle Velocity Measurement

Passive direction finding of acoustic measurement is an important content of acoustic surveillance technology. In order to estimate the direction of the ground target intruded upon the special region, the method of passive bearing estimation with acoustic vector sensors was proposed in this paper. By using the technique for measuring sound pressure, the sound particle velocity was estimated, and the sound particle velocity which is a vector represents the direction of the target. Simulating with noise signal radiated from real target, the results show that the algorithm can achieve direction estimation precision of 2° with the size of acoustic vector sensors 0.3m and signal-noise-ratio 0dB. The experiment on particle velocity directivity of the acoustic vector sensors was also carried out, and gained the figures of the particle velocity directivity of the vector sensor. It is shown in the experiment that the vector sensor has fine space directivity. The experiment results also indicate that the method can reach a high precision, and could be absolutely used to estimate the direction of the ground target.