相关实验视频
Updated: Jul 7, 2025

10:26
Fabrication and Characterization of Superconducting Resonators
Published on: May 21, 2016
11.3K
一个高Q电机磁合共振器用于ELF/SLF跨介质磁性通信
Jianglei Chang1,2, Zhuangzhuang He3, Shupeng Xu4
1College of Civil and Transportation Engineering, Shenzhen University, Shenzhen, 518060, China.
Advanced materials (Deerfield Beach, Fla.)
|December 26, 2023
概括
一个厘米尺度的共振器有效地传输极低/超低频 (ELF/SLF) 信号,用于跨媒介通信. 这种新型设备提供了显著更高的效率和更短的放松时间,使便携式水下和地下通信成为可能.
科学领域:
- 电磁学 电磁学 电磁学 电磁学
- 材料科学 材料科学 材料科学
- 通信工程 通信工程
背景情况:
- 高频电磁波在具有挑战性的跨介质环境中迅速减弱.
- 传统的用于极低频/超低频 (ELF/SLF) 通信的天线需要不切实际的大型结构 (>10公里).
研究的目的:
- 为ELF/SLF跨媒介磁性通信开发一个紧的,高效的天线.
- 克服现有天线技术的局限性,用于地下和水下应用.
主要方法:
- 一个压电陶/铁磁异质结构的,悬臂束型振荡器的制造.
- 设计一个硬软混合动力阶段刚性弹性梁,以提高质量因子 (Q).
- 实现一个振幅相位移键 (ASK+PSK) 调制,以抑制放松时间.
主要成果:
- 该共振器实现了ELF/SLF磁场传输的高质量系数 (Q ≈240),比以前的天线高出数量级.
- 与传统天线相比,磁场发射效率增加了5000倍,发射能力增加了200%.
- 使用拟议的调制方法,实现了对共振器放松时间的80%的减少.
结论:
- 厘米尺度的共振器代表了有效的ELF/SLF磁性通信的突破.
- 成功的空气-海水跨媒介通信证明了其作为水下和地下环境的便携式高性能天线的潜力.
相关概念视频
Double Resonance Techniques: Overview
213
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...
213
Electromagnetic Fields
2.1K
Electric fields generated by static charges, often referred to as electrostatic fields, are characteristically different from electric fields created by time-varying magnetic fields. While the former is a conservative field, implying that no net work is done on a test charge if it goes around in a complete loop in the field, the latter is, by definition, not a conservative field; net work is done, and it is proportional to the rate of change of magnetic flux.
However, the observation of...
However, the observation of...
2.1K
Magnetic Field Due to Two Straight Wires
2.5K
Consider two parallel straight wires carrying a current of 10 A and 20 A in the same direction and separated by a distance of 20 cm. Calculate the magnetic field at a point "P2", midway between the wires. Also, evaluate the magnetic field when the direction of the current is reversed in the second wire.
2.5K
Magnetic Field Due To A Thin Straight Wire
4.9K
Consider an infinitely long straight wire carrying a current I. The magnetic field at point P at a distance a from the origin can be calculated using the Biot-Savart law.
4.9K
Generating Electromagnetic Radiations
2.9K
The German physicist Heinrich Hertz (1857–1894) was the first to generate and detect certain types of electromagnetic waves in the laboratory. Starting in 1887, he performed a series of experiments that confirmed the existence of electromagnetic waves and verified that they travel at the speed of light. Hertz used an alternating-current RLC (resistor-inductor-capacitor) circuit that resonated at a known frequency and connected it to a loop of wire. High voltages induced across the gap in...
2.9K
Magnetic Field Of A Current Loop
4.6K
Consider a circular loop with a radius a, that carries a current I. The magnetic field due to the current at an arbitrary point P along the axis of the loop can be calculated using the Biot-Savart law.
4.6K

