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Array gain for a cylindrical array with baffle scatter effects
Derek C Bertilone1, Damien S Killeen, Chaoying Bao
1Defence Science and Technology Organisation, Building A51, HMAS Stirling, P.O. Box 2188, Rockingham DC, Western Australia 6958 Australia. derek.bertilone@dsto.defence.gov.au
The Journal of the Acoustical Society of America
|January 15, 2008
Summary
This study models high-frequency sonar array gain, accounting for baffle scatter and ambient noise. Results show interference between incident and scattered fields degrades array performance.
Area of Science:
- Acoustics
- Underwater surveillance technology
- Signal processing
Background:
- Cylindrical arrays with sensors around a baffle are common in passive sonar.
- In some systems, phones are hardwired, creating a baffled circular array of directional elements.
Purpose of the Study:
- To introduce a model for computing high-frequency array gain in cylindrical sonar arrays.
- To incorporate baffle scatter using infinite, rigid cylinder scattering theory.
- To analyze array gain degradation due to baffle interference.
Main Methods:
- Developed a model for high-frequency array gain computation.
- Incorporated baffle scatter via infinite, rigid cylinder scattering theory.
- Described ambient noise using an angular spectral density function.
Main Results:
- The model illustrates array gain degradation at high frequencies.
- Acoustic fields sampled by staves are distorted by incident and scattered field interference.
- Gain degradation is shown for 3D isotropic, 2D isotropic, and surface dipole noise distributions.
Conclusions:
- Baffle scatter and sensor offset significantly impact high-frequency sonar array performance.
- Interference patterns between incident and scattered fields are critical factors in array gain.
- The model provides a framework for understanding and mitigating performance loss in cylindrical sonar arrays.
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