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Key research themes
1. How can magneto-mechanical transmitter design optimize ultra-low frequency magnetic induction communications for energy efficiency and compactness?
This theme investigates magneto-mechanical transmitter (MMT) designs utilizing resonant oscillatory motion of permanent magnets to generate ultra-low frequency (ULF) magnetic fields. It addresses engineering challenges in achieving compact, energy-efficient ULF transmitters for near-field communication, particularly underwater and underground, where low-frequency signals penetrate media better. The focus is on the mechanical resonance tuning, multi-rotor architectures for frequency control, and modulation techniques to encode data with minimal power consumption.
Key finding: This paper experimentally demonstrates resonant magneto-mechanical transmitters (MMTs) using single- and multi-rotor permanent magnet rotors oscillating at frequencies from tens of Hz to 1 kHz, achieving high magnetic field... Read more
Key finding: This study presents a wireless power transfer mechanism using resonant oscillations of permanent magnets driven by low-frequency magnetic fields (tens to hundreds of Hz). The approach achieves stable power transfer to... Read more
Key finding: The paper proposes communication protocols adapted to the specific physical characteristics of magnetic induction (MI) communications in near-field challenging media, exploiting low data rate but emphasizing ultra-low power... Read more
2. What advances in coil array configurations and magnetic field shaping improve uniform wireless power transfer and robust communication in dynamic or obstructed environments?
This theme focuses on coil array design and electromagnetic field management to enable wireless power transfer (WPT) and magnetic induction communication (MIC) systems that maintain uniform magnetic field strength, eliminate dead zones (blank spots), and sustain efficient data/power transfer despite mobility, misalignment, or physical obstructions such as metal walls or free movement scenarios. Special attention is paid to multi-coil spatial arrangements, overlapped transmitters, phase control, and metamaterial-enhanced lenses for signal focusing and penetration.
Key finding: This work develops an analytical model for magnetic induction communication through metal walls, identifying an optimal carrier frequency around 1 kHz that maximizes channel capacity by balancing skin depth and attenuation.... Read more
Key finding: The paper introduces a coil array structure with 50% overlap between adjacent transmitter coils to create a spatially uniform electromagnetic field over the receiver’s moving path. This configuration compensates for the power... Read more
Key finding: This study presents an improved phase-calculation method that accounts for coupling between transmitter coils in a multi-input multi-output (MIMO) wireless power transfer system. Compared to conventional phased-array... Read more
3. How can magnetic induction sensing and communication technologies be optimized for harsh and complex environments such as underwater, underground, and biological systems?
This theme covers the development and validation of magnetic induction communication and sensing modalities tailored for environments with severe signal attenuation or complexity, such as underwater media, underground soil, living cells, and implantable devices. Research explores instrumentation models, localization methods, and sensor designs that leverage magnetic induction to achieve reliable communication and high sensitivity, addressing challenges like tissue opacity, signal penetration, energy harvesting, and localization ambiguity.
Key finding: This paper introduces the Cell Rover, a sub-millimeter magnetostrictive antenna operable inside living cells, acoustically actuated at low MHz frequencies optimal for biological systems to minimize heating and maximize power... Read more
Key finding: The article develops a behavioral circuit model of hybrid magnetoelectric (ME) antennas enabling simultaneous wireless RF energy harvesting and low-frequency magnetic field sensing. The system interfaces the ME antenna to... Read more
Key finding: This paper presents a localization approach for magnetic induction communication using triaxial coil antennas based on induced voltage measurements and particle filtering to resolve location ambiguity inherent in near-field... Read more