# Analysis of Electromagnetic Field Characteristics of Wave Glider
## 1 Introduction  
Underwater unmanned systems can perform various tasks such as ocean exploration, underwater monitoring, reconnaissance, anti-mine and anti-submarine operations, and have high civilian and military value. They have gradually assumed important roles in underwater mining, hydrological collection, and other fields. At the same time, underwater unmanned systems have also become important pieces of supporting equipment for major military countries around the world to expand their underwater combat areas and occupy advantages in maritime operations [1, 2]. At present, countries around the world attach great importance to the development of marine resources. There has been a growing interest in the exploration and oceanographic investigation of marine resources, and underwater attack and defense combat systems are facing enormous pressure. Unmanned equipment, represented by unmanned underwater vehicles, plays an increasingly important role in the future exploration of underwater resources and underwater confrontation [3, 4, 5]. As a new type of underwater observation platform that converts wave energy into motion energy, wave gliders rely on their own structural characteristics to achieve continuous detection of the underwater environment under different sea conditions, and because of their advantages in the field of observation, a variety of wave gliders equipped with various types of sensors have been used in related fields. Currently, a large number of studies on path planning for wave gliders have been conducted in academia. The methods used in reference [6] include the weight-heuristic A* algorithm and WAPF algorithm, and in order to ensure the efficient navigation of wave gliders in complex marine environments and to maintain their controllability in upwind or downwind conditions, a hybrid path planning method aiming at path time consumption and safety was proposed. Meanwhile, [PERSON] et al. [7] investigated the interference and nonlinear effects caused by the interaction between the propeller and rudder in a wave glider with a special double-body structure and a higher maneuverability propeller-rudder control system. They proposed an improved adaptive model predictive control based on model predictive control, which can adaptively adjust the size of the prediction interval and the weight value of the rudder and the propeller according to the heading requirements. References [8; 9] and others have studied the operation of wave gliders under different working conditions and formation conditions, and it is known that wave gliders have perfect working performance. For the field of underwater detection using wave gliders, [PERSON] [10] designed measurement trajectories and found that the GNSS-a based on wave gliders can provide centimeter-level horizontal positioning accuracy for a single transmitter in shallow water, even if the sound speed model differs from the actual value by a few meters per second, making low-cost GNSS-A surveys in shallow water areas a promising reality. [PERSON] [11] proposed a real-time ship detection system based on the YOLOv5s like CBAM model, equipped with a visual detection and recognition system using a wave glider. A lightweight YOLOv5s like CBAM model was proposed, which was embedded in the Jetson nano-A02 development board to achieve long-term recognition and monitoring of ships at sea in low-power mode, making the application of wave gliders in automatic coastal patrol more promising. The authors of [12; 13; 14; 15] developed a low noise detection system for passive acoustic monitoring of marine mammals by using a wave glider equipped with a low-power towed hydrophone array and an embedded digital signal processor.