Internet-of-Things (IoT) is expected to connect tens of billions of devices anytime and anywhere and enable a wide range of services such as smart city, connected vehicles, and health care [1]. Recent advancements have driven the rapid growth of IoT in 5G technologies along with cloud- and edge-computing-enabled big-data analytics. However, one typical drawback of the existing IoT solution is the limited lifetime due to the massive number of IoT devices being powered by batteries with finite capacities. Therefore, keeping a large number of energy-constrained IoT devices alive poses a key design challenge. To this end, Backscatter Communication (BackCom) has emerged as a promising technology, allowing IoT devices to transmit data with low-power consumption. Moreover, its low-complexity design and small form factor make BackCom more attractive by realizing cost-effective IoT deployment. We organize the remainder of this chapter as follows. In Section 7.1, we provide fundamental knowledge for BackCom, including the basic principles, key design parameters, and standardization. Then, we summarize several BackCom networks in Section 7.2 and introduce several advanced emerging communication technologies redesigned for BackCom in Section 7.3. In Section 7.4, we explain several performance improvement methods of BackCom. Next, we focus on the applications empowered by BackCom in Section 7.5. Last, we discuss the open issues and future directions of BackCom in Section 7.6.

Chapter Contents:

• 7.1 BackCom basic principle
• 7.1.1 Architecture
• 7.1.2 Modes and modulation
• 7.1.3 Design parameters
• 7.1.3.1 Operating frequency
• 7.1.3.2 Impedance matching
• 7.1.3.3 Antenna gain
• 7.1.3.4 Polarization
• 7.1.4 Standardization
• 7.2 BackCom networks
• 7.2.1 BackCom networks
• 7.2.1.1 Monostatic BackCom networks
• 7.2.1.2 Bistatic BackCom networks
• 7.2.2 Multi-access BackCom network
• 7.2.3 Interference BackCom network
• 7.3 Emerging backscatter communication technologies
• 7.3.1 Ambient BackCom
• 7.3.2 Wirelessly powered BackCom
• 7.3.3 Full-duplex BackCom
• 7.3.4 Visible-light-BackCom
• 7.3.5 BackCom system with technology conversion
• 7.4 Performance enhancements of backscatter communication
• 7.4.1 Waveform design
• 7.4.1.1 Single-tag case
• 7.4.1.2 Multi-tag case
• 7.4.2 Multi-antenna transmissions
• 7.4.2.1 Space-time coding
• 7.4.3 Energy beamforming
• 7.5 Applications empowered by backscatter communications
• 7.5.1 BackCom-assisted positioning
• 7.5.2 Smart home and cities
• 7.5.3 Logistics
• 7.5.4 Biomedical applications
• 7.6 Open issues and future directions
• 7.6.1 From wireless information and power transmission to BackCom
• 7.6.2 Security and jamming issues
• 7.6.3 mmWave-based BackCom
• Acknowledgment
• References

Inspec keywords: Internet of Things; 5G mobile communication; Internet

Other keywords: edge-computing-enabled big-data analytics; Backscatter Communication; key design parameters; energy-constrained IoT devices; internet-of-Things; connected vehicles; low-complexity design; cost-effective IoT deployment; low-power consumption; key design challenge; advanced emerging communication technologies; Backscatter communications; BackCom networks; ultra-low-power IoT; health care; 5G technologies; smart city

Subjects: Other computer networks; Computer communications; Internet software; Mobile radio systems