基于压电效应的低频无线通信机械天线

传统电天线的尺寸与其发射电磁波的波长相近。 低频电磁波(30 ~ 300 kHz)的波长达数公里,低频电天线存在尺寸过大、隐蔽性差、功耗大等问题。 为解决电天线尺寸和功耗大的问题,同时提高低频无线通信应用的灵活性,提出了一种基于压电效应的机械天线,机械天线是利用机械运动的电荷直接激励产生电磁波。 研究了压电机械天线工作的物理机理; 通过阻抗-频率曲线研究压电机械天线的阻抗特性; 利用无线通信系统对比了不同边长压电机械天线的低频辐射性能; 同时验证了压电机械天线辐射的磁场随无线通信系统接收端与压电机械天线距离的变化规律。 结果表明,压电机械天线在便携式、低成本和高性能低频无线通信应用中具有巨大潜力。

Low-Frequency Wireless Communication Mechanical Antenna Based on Piezoelectric Effect

The size of traditional electric antenna is proportional to the transmitted wavelength. Althoughthe low-frequency electromagnetic wave (30 ~ 300 kHz) reaches several kilometers, the low-frequencyelectric antenna has some problems, such as excessively large size, poor concealment and high powerconsumption. To solve the problems of large size and power consumption of electrical antenna andimprove the flexibility of low-frequency wireless communication applications, a mechanical antenna basedon piezoelectric effect is proposed. Mechanical antenna generates electromagnetic waves by directexcitation of mechanical motion charges. The physical mechanism of the piezoelectric mechanical antennais studied. The impedance characteristics of piezoelectric mechanical antenna are studied by impedancefrequency curve. The low-frequency radiation performances of piezoelectric mechanical antennas withvarious side lengths are compared by using a wireless communication system. Meanwhile, the magneticfield radiated by piezoelectric mechanical antenna changes with the distance between the receiving end ofwireless communication system and piezoelectric mechanical antenna, and its variation law is verified.The result shows that the piezoelectric mechanical antenna has great potential in portable, low-cost andhigh-performance low-frequency wireless communication applications.