First, the generation mechanism, components and frequency characteristic of radiated noise of naval ships are studied. There exists periodical modulation for the amplitude of propeller noise.
首先讨论了舰船辐射噪声的产生机理、构成和频率特性，指出螺旋桨噪声的振幅存在周期性调制。
2
With vision noise added to the stimulus pictures, the quality of perception decreased, the mental rotation process postponed, and the onset of the amplitudemodulation was delayed.
刺激图片加入视觉干扰后，知觉质量下降，心理旋转加工推后，波幅调制的起始时刻推后。
3
With 1kHz voltage modulation and harmonics detection, residual amplitudemodulation (RAM) noise were carried out experimentally.