Wireless Connectivity for Internet of Things (IoT)

除了对未来无线网络（5G）中的无线连接的传统要求之外，5G网络还具有一些新的挑战性要求，这些要求是对更高比特率、更宽收敛和更低延迟的不断增长的需求。特别是，下一代移动的网络联盟预测，5G网络将需要满足新用例的需求，即所谓的物联网（IoT）。物联网是一种新的网络模式，其中对象或人被提供唯一标识符以及通过网络传输数据的能力，而不需要人与人或人与计算机的交互。换句话说，物联网是物理对象或“事物”的网络，嵌入了电子设备，软件，传感器和连接，使其能够通过互联网基础设施与其他机器和/或人类交换数据。据估计，到2020年，物联网将由近500亿个对象组成。特别是，5G系统应该支持数十万个同时连接的大规模传感器部署。在过去的几十年里，无线技术已经证明了显著的变化;然而，当前的系统远远不能满足预期的未来需求。本研究针对物联网无线连接实现中的一些关键问题进行了研究，包括：（1）超低延迟（<1 msec）、低频谱效率、超可靠（无ARQ）传输。(2)频谱和能源效率，超可靠的传输（无重传）。(3)高速、非协调的多路访问，在下行链路和上行链路的小开销。(4)超节能传输，即，能量与频谱效率的有效折衷的可能性。(5)支持上行链路、下行链路和协作传输中的开环操作。(6)支持上行链路/下行链路中的非协调、低延迟多路访问。（7）数据包级纠错。拟议的研究依赖于跨层的方法，包括RF/PHY和网络层来解决这些挑战。

In addition to conventional requirements for wireless connectivity in future wireless networks (5G), which is a growing demand for higher bit rates, wider converge and lower latency, 5G networks have some new challenging requirements. In particular, Next Generation Mobile Networks Alliance predicts that 5G networks will need to meet the need of a new use-case, the so-called Internet of Things (IoT). The IoT is a new networking paradigm in which objects, or people are provided with unique identifiers and the ability to transfer data over a network without requiring human-to-human or human-to-computer interaction. In other words, IoT is the network of physical objects or "things" embedded with electronics, software, sensors and connectivity to enable it to exchange data with other machines and/or humans through the Internet infrastructure. It is estimated that the IoT will consist of almost 50 billion objects by 2020. In particular, 5G systems should support several hundreds of thousands of simultaneous connections for massive sensor deployments. Wireless technology has evidenced significant changes in the last decades; however, the current systems are far from meeting the projected future demands. The proposed research addresses some of the key questions in conjunction with the realization of IoT wireless connectivity.The proposed research includes: (1) Extra low latency (< 1msec), low spectral efficiency, ultra-reliable (no ARQ) transmission. (2) Spectral and energy efficient, ultra-reliable transmission (no retransmission). (3) High speed, uncoordinated multiple access in down-link and up-link with small overhead. (4) Ultra energy efficient transmission, i.e., possibility to effectively trade-off of energy vs. spectral efficiency. (5) Support for open loop operation in up-link, down-link, and in cooperative transmission. (6) Support for uncoordinated, low latency multiple access in up-link/down-link, (7) Error correction at the packet level. The proposed research relies on a cross layer approach, including RF/PHY and network layers to address these challenges.