A Compact Ship Short-Wave Antenna with Mid-Coil Inductive Loading for Broadband Self-Tuning

To address the urgent demand for miniaturized and broadband antennas in ship communication systems, this paper proposes a novel short-wave broadband self-tuning antenna. The antenna, with a total height of 2 meters, employs a mid-coil inductive loading structure to achieve dynamic multi-frequency tuning by adjusting the effective turns of an air-core coil. A bottom-fed configuration and optimized matching circuit enhance energy transmission efficiency. Simulation and experimental results demonstrate that the antenna achieves a voltage standing wave ratio (VSWR) below 2 across the 3–30 MHz short-wave band, with a low-frequency bandwidth of 9 kHz and high-frequency tuning accuracy errors below 20%. This design provides a viable solution for efficient short-wave communication in spatially constrained ship environments.