volume | PIER Journals

Abstract

In this paper, a high-efficiency, center-fed dynamic seawater monopole antenna is proposed. The antenna's radiation efficiency increases by raising the feed point position, adding a metal tube above the feed point, and reducing the inner diameter of the water pipe below the feed point. Concurrently, the effects of the feeding position, the length of the metal pipe and the inner diameter of the water supply pipe on the current distribution are analyzed by theoretical modeling. FEKO electromagnetic simulation software is applied to simulate and analyze metal tubes with different lengths and water supply side pipes with different inner diameters. The simulation results indicate that the antenna attains optimal performance when being configured with a water supply pipe of 1 cm inner diameter and a 30 cm metal tube, achieving a maximum gain of 0.93 dBi and a peak radiation efficiency of 52%. Based on the simulation data, a simplified center-fed dynamic seawater antenna prototype is designed and fabricated. Experimental validation confirms that the seawater serves as the primary radiating element. The measured radiation characteristic curves exhibit consistent trends with the simulated results.

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Dr. Xin Zhang

Mrs. Lihua Li

Dr. Mingxuan Hu