An ultra-compact mechanical antenna based on PTFE highly charged electret for extremely low frequency communications

Wenhou Zhang; Zongxin Wang; Zhenxin Cao; Xiaoyu Wang; Mengjiang Sun; Dongning Cui; Ying Chen; Song Ma

doi:10.1016/j.heliyon.2024.e26933

An ultra-compact mechanical antenna based on PTFE highly charged electret for extremely low frequency communications

Heliyon. 2024 Mar 6;10(5):e26933. doi: 10.1016/j.heliyon.2024.e26933. eCollection 2024 Mar 15.

Authors

Wenhou Zhang¹, Zongxin Wang¹, Zhenxin Cao¹, Xiaoyu Wang², Mengjiang Sun¹, Dongning Cui², Ying Chen³, Song Ma³

Affiliations

¹ The school of information science and engineering, Southeast University, Nanjing 210000, China.
² the school of mechanical engineering, Dalian Jiaotong University, Dalian 116000, China.
³ the Southwest China Institute of Electronic Technology,Chengdu 610036, China.

Abstract

-Extremely-Low Frequencies (ELF, 30∼300Hz) transmitting antennas in wireless communications are often limited by antenna size and complex impedance matching networks. In this paper, we propose an ultra-small Artificial Electret Type Mechanical Antenna (AETMA), which is composed of a single charge electret and a driving structure, with high radiation efficiency and small size. In order to improve the electric dipole moment of the mechanical antenna, we employ a pin-plate corona polarization technique and a unidirectional stretching treatment to obtain a porous thin-film electret that can stably store a large amount of charge. Its surface charge density can reach 5.355 mC/m² and we analyze its surface potential stability. To assess the radiation capability of AETMA, the radiation field models of three kinds of mechanical antennas are established and verified by simulation. Additionally, we simulate and compare the planar electret and curved electret configurations to determine the optimal form of AETMA. The radiation intensity of the planar electret is found to be superior under the same moment of inertia. Finally, a 1m-scale artificial electret antenna is designed based on the optimal model. Comparative analysis with existing rotary mechanical antenna schemes confirms the great potential of the proposed AETMA for portable, miniaturized and high-performance wireless communication devices.

Keywords: Charge; Extremely-low frequencies; Mechanical antenna; Porous thin film electret.