涡旋电磁波无线通信技术的研究进展

赵林军; 张海林; 刘乃安

doi:10.11999/JEIT200899

涡旋电磁波无线通信技术的研究进展

doi: 10.11999/JEIT200899

赵林军^{1, 2},
张海林^2, ,,
刘乃安²

1.
陕西理工大学物电学院汉中 723000
2.
西安电子科技大学通信工程学院西安 710071

基金项目: 国家自然科学基金(61671347, 61876143)，陕西理工大学人才计划项目(SLGRC20200028)

详细信息

作者简介:
赵林军：男，1973年生，博士，副教授，主要研究方向为无线通信传输技术等

张海林：男，1963年生，博士生导师，主要研究方向为宽带无线通信数字传输关键技术及系统体制标准研究等

刘乃安：男，1966年生，硕士生导师，教授，主要研究方向为无线通信与射频技术、无线局域网(WIFI)、无线分布式网络等

通讯作者:
张海林　hlzhang@xidian.edu.cn

中图分类号: TN92
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出版历程
- 收稿日期: 2020-10-21
- 修回日期: 2021-03-03
- 网络出版日期: 2021-10-23
- 刊出日期: 2021-11-23

Research Status of Vortex Electromagnetic Wave Wireless Communication Technologies

Linjun ZHAO^{1, 2},
Hailin ZHANG^{2
, ,},
Naian LIU²

1.
School of Physics and Telecommunication Engineeringg, Shaanxi University of Technology, Hanzhong 723000, China
2.
School of Telecommunications of Engineering, Xidian University, Xi’an 710071, China

Funds: The National Natural Science Foundation of China (61671347, 61876143), The Talent Introduction Foundation of Shaanxi University of Technology (SLGRC20200028)

摘要

摘要: 由电磁动力学可知，电磁波可携带与极化方式相关的自旋角动量(Spin Angular Momentum, SAM) 和与坡印廷矢量运动方式相关的轨道角动量(Orbital Angular Momentum, OAM)。当OAM不为零时，电磁波的波前电场分布呈漩涡状且具有沿轴向传播的特性，人们形象地将这类电磁波称为涡旋电磁波。学界在平面电磁波场强数学模型的基础上引入了一个以OAM 的拓扑荷$ \ell $ (又称模态)为参数的傅里叶旋转因子描述涡旋电磁波的波前场，因此，涡旋电磁波波前具有与拓扑荷$ \ell $相关联的“极化”图案，利用不同模态的涡旋电磁波的极化图案可进一步提升无线通信系统信道容量。研究表明，在开放环境下由均匀圆阵列(Uniform Circular Array, UCA)阵列产生“平面”涡旋电磁波波束尽管可行，但要获得模态复用增益，需要探索基于复平面内单位圆周上分布的正交相位序列的涡旋电磁波波束产生与信息传输方法。文中也调研了无线射频领域OAM与MIMO体制相兼容的研究现状。
- 涡旋电磁波 /
- 涡旋电磁波MIMO /
- 极化纹理 /
- 轨道角动量 /
- 模态正交分离
Abstract: It is known from electromagnetic momentum that electromagnetic waves can carry Spin Angular Momentum (SAM) related to polarization and Orbital Angular Momentum (OAM) related to the trajectory of the Poynting vector. When OAM is not zero, the wave-front electric field distribution of the electromagnetic wave is vortex-like and has the characteristic of propagating along the axial direction. Therefore, this electromagnetic wave is aptly named vortex electromagnetic wave. Based on the mathematical model of the plane electromagnetic wave field, the researchers introduce a Fourier factor that uses the topological charge (also called mode) of the OAM as a parameter to describe the field of the vortex electromagnetic wave. Therefore, the wave-front of the vortex electromagnetic wave with a “polarization” pattern associated with topological charge, the use of polarization patterns of vortex electromagnetic waves in different modes can further increase the spectrum effect of the wireless communication system. Studies show that although it is feasible to generate "planar" vortex electromagnetic wave beams from Uniform Circular Array (UCA) arrays in an open environment, to obtain modal multiplexing gain, and it is necessary to explore vortex electromagnetic wave beams based on orthogonal phase sequences distributed on a unit circle in the complex plane. At the same time, the paper also investigates the current research status of compatibility between OAM and Multiple Input Multiple Output (MIMO) systems in the field of radio frequency.
- Vortex radio /
- OAM-based MIMO /
- Polarized texture /
- Orbital Angular Momentum (OAM) /
- Mode orthogonal separation

HTML全文

图 1 携带角动量的质点系^[21]

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图 2 电基本阵子角动量密度矢量示意图^[21]

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图 3 携有OAM电磁波坡印廷矢量轨迹及其波前结构示意^[24]

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图 4 涡旋电磁波波前电场相位示意图

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图 5 波束移相法产生涡旋电磁波示意图

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图 6 射频域信号移相馈电网络示意图

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图 7 射频域信号移相馈电网络示意图^[52]

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图 8 相位梯度检测方法示意^[25]

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图 9 部分方位角接收示意图^[53]

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图 10 全方位角采样接收方法示意图^[54]

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图 11 3个OAM复用的MIMO链路示意图^[62]

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图 12 同心圆嵌套时的模态复用OAM MIMO系统示意图^[65]

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图 13 OAM光通信方案示意图^[66]

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图 14 双模态无线室内演示系统示意图^[75]

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