Remote identification of the vibration amplitude of ship hull

Abstract

The aim is to develop the methodological support to determine vibration amplitude of the ship hull remotely using a coherent radar centimeter range based on the variation of the Doppler signal spectrum reflected from a vibrating surface.The paper presents a synthesized mathematical model of the radio signal reflected from the vibrating surface. It is the signal of coherent radar of continuous radiation with a known carrier frequency and the amplitude of the radiated signal. In the synthesis it was believed that the displacement in the radial direction with respect to the vibrating surface radar was sinusoidal.The dependences of the vibration amplitude on the value of the normalized Doppler radio signal spectrum at the second harmonic frequency are obtained. Cycle results of field experiments to study the variability of the sea surface, determining the level of its roughness, allows us to establish that the energy of surface waves of gravitational-capillary range has a high correlation with the wind speed. It is proved that the ratio of the spectral density levels at vibration frequency and its multiple frequencies is specified by the index of phase modulation linearly related to the amplitude of vibration of the ship hull.The results are significant for radar (radar detection of water targets using the coherent radar of centimeter range), ensuring the correct records of noise generated by the scattering of radio waves from the water surface.

Keywords

• coherent radar station
• radar monitoring of vibration ship hull
• the Doppler signal spectrum
• phase modulation index of radio signal