Accurate data of sound speed and attenuation in sediments are extremely important for the validation of sediment acoustic models. However, given the limitation of operating bandwidth of a transmitter and the uneven transmiting voltage response,the spectral shape of a transmitted acoustic signal is quite different from that of the driving signal. Such a circumstance leads to inaccuracy of the experimental measurement data. In this study, the actual measured transmitting voltage response of a transducer was used to compensate for the driving signal for e-qualizing the frequency response of a narrowband transmitter and weakening the effect of the transducer on the transmitted signal. Numerical results indicate the efficiency of the proposed method. Laboratory measurements also show that the central frequency shift of the transmitted narrowband acoustic signals was constrained after the driving signal was compensated. The bandwidth of the transmitted broadband acoustic signal was much closer to that of the driving signal. Besides, the method widened the effective bandwidth of narrowband measurements, reduced the fluctuation of broadband sound speed and attenuation data, narrowed the difference between broadband data and narrowband data,and improved experimental accuracy.%准确的沉积物声速和衰减数据对于沉积物声学模型的验证极其重要,但是由于实际声源工作带宽的限制以及发送电压响应不平坦,造成了发射声信号频谱形状改变,导致实验测量数据不准确.为此,本文采用实测的换能器发送电压响应对驱动信号进行补偿,以实现窄带换能器频响特性的均衡,减弱换能器对发射信号的影响.数值仿真验证了本文所提方法的有效性,并且实验结果表明,驱动信号经补偿后,窄带发射声信号中心频率的偏移得到有效抑制,宽带发射声信号的带宽与驱动信号的带宽更为逼近.同时,该方法拓宽了窄带测量数据的有效带宽,降低了宽带测量获取的声速和衰减数据的起伏,使得窄带和宽带数据更加一致,提升了实验结果的准确性.
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