Inversion for a moving spherical target's positional, structural, and speed parameters.

Area of Science:

• Acoustics
• Signal Processing
• Underwater Acoustics

Background:

• Target echoes in shallow water are affected by multipath arrivals and waveguide propagation.
• Moving targets introduce Doppler shifts, complicating echo analysis and target classification.
• Distinguishing target echoes from clutter relies on broadband scattering characteristics.

Purpose of the Study:

• To investigate the simultaneous determination of a spherical target's position (range, depth), radial speed, radius, shell thickness, and elastic parameters.
• To assess the accuracy of parameter estimation from a single wideband echo in a waveguide environment.
• To analyze the marginal probability distributions of estimated parameters.

Main Methods:

• Analysis of broadband scattering characteristics of spherical targets in shallow water waveguides.
• Processing of wideband echoes considering multipath interference and Doppler shifts.
• Estimation of target parameters using single-echo data and investigation of probability distributions.

Main Results:

• Accurate estimation of multiple target parameters (position, speed, radius, shell properties) from a single wideband echo is achievable.
• Positional and speed parameters of the sphere can be determined with high precision.
• Parameter estimation accuracy varies, with some parameters determined more precisely than others, even in noisy conditions.

Conclusions:

• A single wideband echo contains sufficient information for robust spherical target characterization in shallow water.
• The method offers a promising approach for target identification and tracking in complex underwater acoustic environments.
• Understanding interference effects and Doppler shifts is crucial for accurate target parameter estimation.