Enabling Low-Power Long-Range Backscatter Communication Networks

互联和嵌入式设备的激增在下一代物联网(IoT)的发展中发挥了关键作用，从而推动了低功耗设备的普及。这种网络的可持续性需要有能源意识的设备，这些设备能够通过从各种来源收集和回收能源来实现自我可持续的运营。因此，后向散射通信(BackCom)，其中后向散射发射器通过后向散射环境信号(例如Wi-Fi信号)向目的地发送数据，最近已成为后5G时代的一项有前途的关键技术。由于其低功耗，BackCom被认为是产生无电池物联网、大规模机器类型通信和设备到设备通信的有力候选者。尽管如此，BackCom系统仍然存在几个缺点，包括低数据速率、短距离通信以及对环境信号动态的依赖。在这项研究中，我们设想将长距离(LORA)、无线供电网络(WPN)和BackCom集成在一个网络中，作为解决上述一些挑战的新范式。然而，这些技术并没有针对大规模无线网络和大量物联网设备进行优化和/或设计。此外，这种系统不同于以人为中心的通信，具有多样化和独特的业务特性以及服务质量(Qos)要求，这需要开发有效的物理层和媒体访问控制(MAC)方案来防止访问拥塞。拟议的研究将实现无电池物联网设备的愿景，并在后向散射通信和射频能量收集方面提供非增量进展。这将通过设计物理/MAC协议来实现，这些协议可以支持具有不同服务质量要求的大量物联网设备、智能电源管理方案和超低功耗收发器架构。这项新颖的研究将对科学界、行业和标准化机构中处于无线系统和物联网前沿的人非常有益。最重要的是，拟议的研究将培养高素质的人员，他们将是物联网未来国际倡议的先驱，而不是跟随者。

The proliferation of connected and embedded devices has played a critical role in the development of the next-generation Internet of Things (IoT) and, consequently, the diffusion of low power devices. The sustainability of such networks entails energy-aware devices that are capable of self-sustainable operations by harvesting and recycling energy from various sources. Accordingly, backscatter communication (BackCom), in which a backscatter transmitter sends data to a destination by backscattering ambient signals, e.g., Wi-Fi signals, has recently emerged as a promising key technology for the post-5G era. Due to its low power consumption, BackCom is envisioned as a strong candidate for the generation of battery-free IoT, massive machine-type communication, and device-to-device communications. Nonetheless, BackCom systems still suffer from several drawbacks, including low data rate, short-range communications, and dependence on the dynamics of ambient signals. In this research, we envisage the integration of long range (LoRa), which is one of the prominent low power wide area networks (LPWAN) technologies, wireless-powered networks (WPN), and BackCom in a single network as a new paradigm for addressing some of the challenges above. However, these technologies are not optimized and/or designed for large-scale wireless networks and a massive number of IoT devices. Also, such systems are different from human-centric communications, with diverse and unique traffic characteristics as well as Quality-of-Service (QoS) requirements, which require the development of efficient physical (PHY)-layer and media access control (MAC) schemes to prevent access congestions. The proposed research will realize the vision of battery-free IoT devices and provides non-incremental advances in backscatter communications and RF energy harvesting. This will be achieved by designing physical/MAC protocols that can support a large number of IoT devices with distinct QoS requirements, smart power management schemes, and ultra-low power transceiver architectures. This novel research will be highly beneficial to those in the scientific community, industry, and standardization bodies who are at the cutting edge of wireless systems, and IoT. Most importantly, the proposed research will train highly qualified personnel, who will pioneer rather than trail international initiatives in the future of IoT.