It has been verified that the directional characters in nearsoundfield in low and middle frequency bands and the pressure level in far...
计算结果正确预测出近场中低频段的指向性特点和远场声压级水平，与实测谱值有较好的一致性。
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Using the finite difference time-domain (FDTD) method and nearfield to far field transformation, pressure of the reflected sound from the scattering target is calculated.
The sound pressure at near distance under free field was computed by using the wave number integration and the basic characteristics of the radiated noise were analyzes.