Underwater Ambiguity Elimination Method Based on Co-Prime Sensor Array.

Area of Science:

• Acoustics and Signal Processing
• Array Signal Processing
• Underwater Sensing

Background:

• Co-prime arrays offer advantages over traditional uniform linear arrays for underwater direction of arrival (DOA) estimation.
• Conventional beamforming with co-prime arrays suffers from grating lobes due to sparse sampling, degrading spatial spectra and estimation performance.

Purpose of the Study:

• To improve the reliability and accuracy of DOA estimation in underwater scenarios using co-prime arrays.
• To address the performance degradation caused by grating lobes in sparse co-prime arrays.

Main Methods:

• Capon beamforming is utilized as a preprocessing step for high-resolution DOA estimation methods.
• Amplitudes from subarray beam-domain outputs and phases from spatial spectrum cross-spectra are extracted.
• These extracted features are used to suppress spurious peaks and eliminate ambiguities in the beam pattern.

Main Results:

• The proposed method effectively suppresses spurious peaks in beam patterns, mitigating interference.
• Ambiguities in DOA estimation are eliminated, leading to improved performance.
• Simulations demonstrate enhanced reliability and accuracy in DOA estimation.

Conclusions:

• The integration of Capon beamforming with co-prime arrays significantly enhances underwater DOA estimation.
• The technique offers practical value by improving the accuracy and robustness of direction finding systems.
• This approach guarantees the performance of high-resolution DOA estimation methods in challenging underwater environments.