部分浸没于海水中天线阻抗及辐射效率分析

针对海洋环境中浮标天线的辐射性能问题，基于海水中短波、超短波频段高衰减的特性，提出了以海面为分界面，将天线分为水上、水下两部分考虑的假设，建立了部分浸没于海水中天线的理论计算模型，开展了天线输入阻抗测试实验，验证了假设和模型的正确性. 应用该模型，确定了天线的水上、水下部分阻抗共轭匹配条件下的工作频率范围，分析了不同入水深度、绝缘层半径以及绝缘层相对介电常数对辐射效率的影响. 结果表明:通过调节天线频率、天线调谐器阻抗、绝缘层材质及厚度等参数，可实现浮标天线的有效辐射，为海洋电磁波通信提供支撑.

Impedance characteristics and radiation efficiency of partially submerged antenna in seawater

In view of the radiation performance of buoy antenna in the marine environment, based on the characteristics of the high attenuation in short-wave and ultra-short-wave frequency bands in seawater, this paper proposes an assumption that the antenna is divided into two parts, the water and underwater, using the sea surface as the interface, and an antenna model that is partially submerged in seawater is established. Based on the theoretical calculation model of the antenna in seawater, the hypothesis and the model are verified by carrying out the antenna input impedance test experiment. Using the model, the working frequency range of the underwater part and the underwater impedance conjugate matching conditions are determined, and how the length of the underwater part and the dielectric parameters of the insulating layer affect the radiation efficiency are analyzed. The results show that the effective radiation of the buoy antenna can be achieved by adjusting the antenna frequency, the impedance of the antenna tuner, the material and thickness of the insulating layer, and so on, thus, providing support for marine electromagnetic wave communication.