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推导出了考虑海底沉积物中声衰减和横波后浅海中点声源激发声场的积分表达式，并用实轴积分法和快速傅里叶交换（ＦＦＴ）数值计算模拟了爆炸声源在浅海中激发的全波列波形。考察了海底沉积物参数、声源激发主频等对低频声传播的影响。研究表明：在远场接收到的波群为声源主频处的模式波。最后讨论了通过几个不同声源激发主频处的某一模式波的群速度的测量值用最小平方和估计法来反演海底沉积物的纵波速度和横波速度的可能性。
The integral expression of acoustic excitation field considering the acoustic attenuation in the seafloor sediment and the sound source in the midpoint of the shallow sea after the shear wave is deduced. The real excitation and the fast Fourier transform (FFT) are used to simulate the excitation of the explosive source in the shallow sea Full wave form. The effects of seabed sediment parameters and excitation frequency of sound source on low frequency sound transmission were investigated. The research shows that the wave group received in the far field is the mode wave at the dominant frequency of the sound source. Finally, the possibility of inverting the P-wave velocity and S-wave velocity of seafloor sediments by using the least-squares-sum estimation method is discussed in the last part by using the measured values of the group velocity of a certain mode wave excited at the fundamental frequency by several different sound sources.