无源物联网：背景、概念、挑战及研究进展

郑黎明; 刘培国; 王宏义; 吴建飞

doi:10.11999/JEIT221219

无源物联网：背景、概念、挑战及研究进展

doi: 10.11999/JEIT221219

国防科技大学电子科学学院长沙 410073

基金项目: 国家自然科学基金(52101391)

详细信息

作者简介:
郑黎明：男，副研究员，研究方向为物联网、传感器、后向散射通信、能量收集

刘培国：男，教授，研究方向为物联网、电磁兼容、电磁防护

王宏义：男，研究员，研究方向为物联网、传感器、后向散射通信、能量收集

吴建飞：男，副研究员，研究方向为物联网、传感器、电磁兼容

通讯作者:
郑黎明　lmzheng@nudt.edu.cn

中图分类号: TN915; TP393
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- 被引次数: 0
出版历程
- 收稿日期: 2022-09-19
- 修回日期: 2023-02-17
- 网络出版日期: 2023-02-21
- 刊出日期: 2023-07-10

Passive Internet of Things: Background, Concept, Challenges and Progress

College of Electronic Science and Technology, National University of Defense Technology, Changsha 410073, China

Funds: The National Natural Science Foundation of China (52101391)

摘要

摘要: 近年来，随着物联网(IoT)部署范围不断扩大，数以千亿计的智能设备将接入物联网，对网络接入能力、能量供应、成本等提出了极大挑战，无源物联网呼之欲出。该文梳理了无源物联网相关概念并给出其定义，首次系统研究了无源物联网面临的能量密度低、转化效率低、后向散射通信距离有限、能量信息同时传输兼顾难等4大挑战，详细分析了问题原因并对研究进展进行综述：针对能量密度低挑战，从波束成形、能量收集天线设计、智能反射表面3个方面综述；针对能量转换效率低挑战，从接收机架构优化、波形设计、阻抗匹配优化、整流器优化4个方面综述；针对后向散射通信距离有限挑战，从新的调制方式、频移型后向散射新机制、MIMO增强、新的信道编码机制、新的信号检测方法、智能反射表面增强以及半有源模式7个方面综述；针对能量信息同时传输兼顾难问题，从能量信息同时传输架构优化、能量信息兼容信道编码2个方面综述。针对每个优化方向，对比分析了各类方法的优劣并指出了未来研究方向。
- 无源物联网 /
- 射频能量收集 /
- 后向散射 /
- 能量信息同时传输
Abstract: In the past decades, the scope of Internet of Things (IoT) is expanded continuously. With hundreds of billions of smart devices connect to IoT, huge challenges are arisen from several aspects such as device cost, connectivity capability, and power supplies. Fortunately, the new paradigm - passive IoT is coming which is one of the effective solutions for these challenges. Some related concepts are analyzed and the definition of passive IoT is proposed. For the first time, the four challenges faced by passive IoT, such as low energy density, low conversion efficiency, limited distance of backscatter communication, and difficulty in transmission of power and information simultaneous, are studied. The problems are analyzed in deeply and the research progress are surveyed. For the challenge of low energy density, the research progress is reviewed from three aspects: beamforming, antenna design for energy harvesting, and intelligent reflecting surface. For the challenge of low energy conversion efficiency, from receiver architecture optimization, waveform design, impedance matching, rectifier optimization. For the challenge of limited distance of backscatter communication, the research progress is reviewed from seven aspects: new modulation scheme, new frequency-shifted backscattering scheme, MIMO, new channel coding scheme, new signal detection method, intelligent reflecting surface enhancing, and semi-active mode. Considering the difficulty in transmission of power and information simultaneous, the research progress is reviewed from two aspects: optimization of the receiver architecture and the energy information compatible signal coding scheme. For each aspect, the advantages and disadvantages of various methods are analyzed and the future research directions are pointed out.
- Passive Internet of Things (IoT) /
- Radio frequency energy harvesting /
- Backscatter communications /
- Simultaneous wireless information and power transfer

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图 1 射频能量收集系统框图

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图 2 RFID系统框图

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图 3 后向散射系统框图

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表 1 缩写表

缩写	英文内容	中文内容	缩写	英文内容	中文内容
IoT	Internet of Things	物联网	NB-IoT	Narrow Band Internet of Things	窄带物联网
LoRa	Long Range Radio	远距离无线电	LPWAN	Low Power Wide Area Network	低功耗广域网
RFEH	Radio Frequency Energy Harvesting	射频能量收集	RFID	Radio Frequency Identification	射频识别
BC	Backscatter Communication	后向散射通信	SWIPT	Simultaneous Wireless Information and Power Transfer	能量信号同时传输
IRS	Intelligent Reflecting Surface	智能超表面	WET	Wireless Energy Transmission	无线能量传输
WIT	Wireless Information Transmission	无线信号传输	ASK	Amplitude-shift Keying	幅移键控调制
FSK	Frequency-shift Keying	频移键控调制	PSK	Phase-shift Keying	相移键控调制
BER	Bit Error Ratio	误码率	MIMO	Multiple Input Multiple Output	多进多出
MISO	Multiple Input Single Output	多进单出	POW	Power Optimized Waveforms	最大功率波形
OFDM	Orthogonal Frequency Division Multiplexing	正交频分复用	DLI	Direct Link Interference	直接传输干扰
OOK	On-off Keying	开关调制	BPSK	Binary Phase Shift Keying	二进制相移键控
QAM	Quadrature Amplitude Modulation	正交振幅调制	MSK	Minimum Shift Keying	最小频移键控
MOS	Metal-Oxide-Semiconductor Field-Effect Transistor	金属-氧化物半导体场效应管	CMOS	Complementary Metal Oxide Semiconductor	互补金属氧化物半导体

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