基于磁遮挡技术的超低频机械天线幅度调制方法  

Amplitude modulation method of super-low frequency mechanical antenna based on magnetic shielding technology

作　　者：宋忠国[1] 崔浩歌 席晓莉[1] Song Zhongguo;Cui Haoge;Xi Xiaoli(School of Automation and Information Engineering,Xi'an University of Technology,Xi'an 710048,China)

机构地区：[1]西安理工大学自动化与信息工程学院,陕西西安710048

出　　处：《电子技术应用》2021年第5期126-130,134,共6页Application of Electronic Technique

基　　金：国家自然科学基金(51707152);中国博士后科学基金(2014-M562522XB);陕西省自然科学基金(2016JQ4023)。

摘　　要：机械天线是利用磁(极)性材料做机械运动来辐射低频信号的新型辐射机理,有望解决现有低频电天线体积大、功耗高、效率低等问题。近年来机械旋转式发射天线的研究中普遍采用的频率调制在机械驱动方面存在局限性,提出一种基于磁遮挡技术的超低频(30~300 Hz)机械天线幅度调制方法,将辐射和调制分离并独立进行。调制器通过“打开”和“闭合”两种状态控制向外传播的总场的衰减来实现调幅;采用三轴正交线圈接收不同极化方向的信号。分析了旋转永磁体产生的电磁场特性,对调制进行了仿真,搭建了实验样机验证了所提方法的可行性。实验结果表明,信息调制无需永磁体频繁改变转速,从而克服了旋转式发射天线频率调制面临的机械挑战。Mechanical antenna is a new radiation mechanism that uses magnetic(polar)materials to radiate low-frequency signals,which is expected to solve the problems of large volume,high power consumption and low efficiency of existing low-frequency electrical antennas.In recent years,frequency modulation,which is widely used in the research of mechanical rotary transmitting antenna,has limitations in mechanical drive.This paper proposes a super-low frequency(30~300 Hz)mechanical antenna amplitude modulation method based on magnetic shielding technology,which separates radiation and modulation and performs them independently.The modulator controls the attenuation of the total field propagating outward through the states"open"and"closed"to realize amplitude modulation.Three-axis orthogonal coils are used to receive signals with different polarization directions.The characteristics of electromagnetic field generated by rotating permanent magnet are analyzed,the modulation is simulated,and an experimental prototype is built to verify the feasibility of the proposed method.The experimental results show that the information modulation does not need the permanent magnet to change the rotating speed frequently,thus overcoming the mechanical challenge faced by the frequency modulation of the rotary transmitting antenna.

关 键 词：超低频 机械天线 旋转永磁体 幅度调制 

分 类 号：TN95[电子电信—信号与信息处理]