In this letter, we examine underwater wireless communications using electromagnetic waves in marine shallow waters. Due to the particular environment under study (low frequencies, short distances, and small loop antennas), a magnetoquasi-static approach is used instead of full-wave analysis. The electric field generated by a constant current circular loop placed on the interface between two conductors is analytically calculated. Using this electric field, the mutual coupling coefficient between the two loops is calculated, and a simple circuit model for transmitting energy from one loop to another is presented using a transformerlike element. Simulations using the circuit model and a commercial full-wave simulator are carried out, and their results are compared. Very good agreement is observed between both results.

中文翻译：

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海底两个水平环路之间电力链路预算的电路模型}

在这封信中，我们研究了在海洋浅水中使用电磁波的水下无线通信。由于正在研究的特定环境（低频、短距离和小环形天线），使用磁准静态方法代替全波分析。解析计算了放置在两个导体之间的界面上的恒流圆环所产生的电场。使用该电场，计算两个回路之间的互耦合系数，并使用类似变压器的元件呈现用于将能量从一个回路传输到另一个回路的简单电路模型。使用电路模型和商用全波仿真器进行仿真，并比较它们的结果。在两个结果之间观察到非常好的一致性。