Interest in wideband and medium distance underwater acoustic communication systems is increasing due to the practical application of underwater Internet of Things (IoT) networks. In this paper, we propose a simplified empirical channel model for the medium distance underwater acoustic channels based on real measurement results. The simple and tractable channel model is critical for the development of advanced underwater communications technology. The underwater channel measurements were performed at 20 m sea water depth, the transmitters (TXs) were located at 5 m and 15 m from the bottom, the receivers (RXs) were located at 4 m, 8 m, 12 m, and 16 m from the bottom, and the TX–RX distances were 21 m, 71 m, 127 m, and 273 m. We derived the path loss from the measured dataset, and modified the log-distance model to create a model suitable for an underwater IoT channel. Numerical results show that the proposed model is accurate and reliable enough to use in the development of advanced underwater communication technologies.

由于水下物联网（IoT）网络的实际应用，对宽带和中距离水下声通信系统的兴趣正在增加。在本文中，我们基于实际测量结果为中距离水下声学通道提出了一个简化的经验通道模型。简单易处理的信道模型对于开发先进的水下通信技术至关重要。水下通道测量是在20 m海水深度下进行的，发射器（TXs）位于距底部5 m和15 m处，接收器（RXs）位于4 m，8 m，12 m和16 m处从底部开始，TX-RX距离分别为21 m，71 m，127 m和273 m。我们从测得的数据集中得出路径损耗，并修改了对数距离模型，以创建适用于水下物联网通道的模型。数值结果表明，该模型准确，可靠，足以用于先进的水下通信技术的开发。