Do Snapping Shrimp Chorus in Time or Cluster in Space? Temporal-spatial Studies of High-frequency Ambient Noise in Singapore Waters
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چکیده
Snapping shrimp dominate ambient noise over 2–300 kHz in warm shallow water. To investigate spatial & temporal behaviour, a stochastic tomographic inversion experiment & signal-processing algorithm have been designed. The experiment uses a set of directional hydrophones with parabolic acoustic mirrors steered in azimuth and elevation by onboard microprocessor systems with pitch and heading sensors. The hydrophones girdle an area of ~2000 m of seabed in approximately 12m of water depth. Acoustic signals are acquired over 20-80 kHz. An initial deployment was conducted in March 2000. Raw time series clearly show snapping shrimp at all ranges. Horizontal anisotropy is of the order ±3 dB.
منابع مشابه
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تاریخ انتشار 2000