2 research outputs found
Measurement and modeling of the acoustic field near an underwater vehicle and implications for acoustic source localization
This article was published in the Journal of the Acoustical Society of America [© Acoustical Society of America] and is also available at: http://asadl.org/The performance of traditional techniques of passive localization in ocean acoustics such as
time-of-arrival (phase differences) and amplitude ratios measured by multiple receivers may be
degraded when the receivers are placed on an underwater vehicle due to effects of scattering.
However, knowledge of the interference pattern caused by scattering provides a potential
enhancement to traditional source localization techniques. Results based on a study using data from
a multi-element receiving array mounted on the inner shroud of an autonomous underwater vehicle
show that scattering causes the localization ambiguities side lobes to decrease in overall level and
to move closer to the true source location, thereby improving localization performance, for signals
in the frequency band 2–8 kHz. These measurements are compared with numerical modeling
results from a two-dimensional time domain finite difference scheme for scattering from two
fluid-loaded cylindrical shells. Measured and numerically modeled results are presented for multiple
source aspect angles and frequencies. Matched field processing techniques quantify the source
localization capabilities for both measurements and numerical modeling output. © 2007 Acoustical Society of America