Future Wireless Networks: Spectral Efficiency, Networking and Security

互联网流量的增长在信息量和数据交换速度方面引发了许多新的研究挑战。无线作为未来的主要接入技术，对这一发展至关重要。作为回应，无线网络一直在发展，以更低的成本支持更高的数据速率和更广泛的覆盖范围。无线连接的瓶颈是频谱，这是一种价格过高的稀缺自然资源。例如，2014年1月，加拿大举行了68兆赫特高频频谱（以前用于地面电视广播）的拍卖。8家加拿大公司赢得了此次拍卖，总价值为52.7亿美元。问题是，不管成本如何，可用的频谱已经被利用/过度拥挤。需要新技术来满足利用可用频谱服务不断增加的移动通信量的需求。尽管有这种需要，但具有实际意义的突破却很少。多输入多输出（MIMO）天线系统，在90年代后期发展起来，导致了显著的改进，并很快在无线产品中找到了自己的方式。在MIMO（最近的突破）之后，PI的团队引入了干涉对准（IA）。IA已经引起了极大的关注，然而，它的实际实施仍然具有挑战性。为了解决未来的需求，需要注意三个相互关联的领域：“传输速率”、“网络”和“安全”。拟议的研究在一个保护伞下解决了这三个领域。主要依靠“全双工无线”解决“传输速率”和“组网”问题，同时采用“基于媒体的调制”技术来提高频谱效率和处理信道衰落问题。全双工无线是一个新的引擎，在提高吞吐量、可靠性、速度和安全性方面为一个全新的未知可能性铺平了道路。提出的研究涵盖了这些领域的一些新应用，从安全到网络管理，干扰抑制和认知传输。研究还包括协作通信、分布式/协同信令、大规模星座的使用和网络信息理论的新方向。拟议的研究将研究提高点对点频谱效率和可靠性的新技术。它还解决了与所谓的“物联网”（IoT）中设想的新兴通信范式相结合的一些关键问题，例如低延迟、开环传输。为了跟上实施更多蜂窝的成本，“云无线接入网络（CRAN）”被作为一种共享资源的机制。拟议的研究将探讨CRAN中前传/回程连接的问题。这项研究的结果预计将对未来几代无线网络产生深远的影响。

The growth in Internet traffic has triggered many new research challenges in the volume of information and how fast data must be exchanged.  Wireless, as the dominant access technology of the future, is vital to this development. In response, wireless networks have been evolving to support higher data rates and wider coverage, at a lower cost. The bottleneck in wireless connectivity is the spectrum, a scarce natural resource with an exorbitant price. As an example, in January 2014, an auction for 68 MHz of UHF spectrum (formerly used for terrestrial TV broadcasting) was held in Canada. Eight Canadian companies won the auction, with total value of $5.27bn. The problem is that, regardless of the cost, the available spectrum is already exploited/overcrowded.  New technologies are needed to meet the demands in servicing an ever-escalating amount of mobile traffic using the available spectrum. In spite of this need, breakthroughs with practical implications have been scarce. Multiple-Input Multiple-Output (MIMO) antenna systems, developed in late 90’s, resulted in a significant improvement and soon found its way in wireless products. After MIMO, a more recent breakthrough, Interference Alignment (IA) was introduced by the PI’s team. IA has attracted significant attention, however, its practical implementation remains challenging.  To address the future needs, three interrelated areas need attention: "transmission rate", "networking" and "security". The proposed research addresses these three areas under one umbrella. The problems of "transmission rate" and "networking" are primarily handled relying on "full-duplex wireless", while a novel technique called "media-based modulation" is applied to increase spectral efficiency and deal with channel fading.  Full-duplex wireless is a new engine, paving the way to a whole new world of unexplored possibilities in improving throughput, reliability, speed and security. The proposed research covers some novel applications in these domains, from security to network management, interference rejection and cognitive transmission.  Research also includes new directions in cooperative communications, distributed/collaborative signaling, use of massive constellations, and network information theory. Proposed research will study new techniques to increase the point-to-point spectral efficiency, and reliability. It also addresses some key issues in conjunction with emerging communications paradigms envisioned in the so-called "Internet of Things" (IoT), such as low delay, open loop transmission.  To keep up with the cost of implementing many more cells, ‘Cloud Radio Access Networks (CRAN)’ is pursued as a mechanism to share resources. Proposed research will investigate the issue of front-haul/back-haul connectivity in CRAN. Findings of the proposed research are expected to have a profound impact on the future generations of wireless networks.