Design and Optimization of Ku-band Large-Loop-Spiral Towed Antenna for the Unmanned Underwater Vehicle

The towed antenna enables the underwater vehicle to communicate across the sea while maintaining its invisibility. In this paper, a Ku-band towed antenna is proposed based on the large loop helix structure. The impedance characteristics of large loop helical antenna are deduced theoretically. Using FEKO electromagnetic simulation software, a layered model of air-sea-towed cable was established to simulate the electrical characteristics of the large loop spiral antenna. According to the simulation results, the length and the number of turns of the large loop spiral antenna are optimized. The results show that the large-loop helical towed antenna can effectively improve the Ku-band signal reception capability of the underwater vehicle in the underwater safe depth range.