Underwater Target Detection by Measuring Water-Surface Vibration With Millimeter-Wave Radar

Underwater target detection has been a significant challenge in environment aware. In this letter, an underwater target detection scheme is proposed by measuring the water-surface vibrations caused by acoustic waves with a millimeter-wave radar. First, the power of the water-surface vibration due to the reflection of acoustic waves by the target is derived, which gives a quantitative relationship between the perturbations on water-surface vibration and the position of the target. Then, the signal model to accurately measure the water-surface vibration with millimeter-wave radar is established. A method to estimate the power spectrum of the phase of water-surface vibrations is proposed, based on which a test statistic for underwater target detection is formulated. Finally, the effectiveness of the proposed scheme is validated by water-tank experiments using a frequency modulated radar with a center frequency of 77 GHz.