CAREER: Coded Modulation for High-Speed Wireless Communications

现代通信的主要目标之一是开发一种系统，为用户提供高速无处不在的信息访问。这样的系统需要无线组件；然而，由于有限的可用带宽和无线环境固有的多路径导致的信号衰落，无线组件可能成为系统的瓶颈。因此，通信研究界被要求对多径衰落信道上的带宽高效通信进行重点研究，并教育学生，使他们具备必要的技能，为这个和未来的系统做出贡献。如下所述，本项目正通过以下途径解决这些问题：(1)高速无线系统编码调制的进展，(2)高速无线系统物理层系统架构的比较，(3)在学生教学中广泛适用的创新，以及(4)通信理论的本科生研究计划。未来高速无线通信系统的两种主要架构是在接收端采用决策反馈均衡器（DFE）的编码单载波系统和编码正交频分复用（OFDM）系统。本课题对OFDM系统的编码调制设计问题进行了研究。通过在频域编码调制（FDCM）的更一般框架中看待这个问题，人们正在开发设计规则，使系统能够有效地权衡复杂性，从而相对于传统的OFDM系统提高误码率和放大器效率。此外，该项目正在分析最终系统作为采用DFE的编码单载波系统和编码OFDM系统之间的混合系统的效用；这为高速无线通信提供了最广泛考虑的系统架构的统一比较。这个项目的教育部分采用了三种互补的方法，努力通过创新来促进学生的学习，补充传统的课堂教学。第一种方法是继续在传统课程中引入支持主动学习的补充内容，例如在本科概率论课程中引入课程点数的机会游戏。第二种方法是开发一门顶级无线通信课程，使研究生和高级本科生能够在注重整体系统性能的团队导向环境中整合各种通信系统组件的知识。最后，第三种方法是继续资助本科生研究项目，通过在活跃的研究环境中提供一对一的关注，帮助有前途的本科生工程师。

One of the major goals of modern communications is to develop a system that provides users high-speed ubiquitous access to information. Such a system requires a wireless component; however, because of the limited amount of bandwidth available and the signal fading due to the multipath inherent to the wireless environment, the wireless component can be the bottleneck of the system. Thus, the communications research community is called upon to provide focused research on bandwidth efficient communications over multipath fading channels and to educate students so that they have thenecessary skills to contribute to this and future systems. As detailed below, this project is addressing these issues through: (1) advances in coded modulation for high-speed wireless systems, (2) a comparison of system architectures for the physical layer of high-speed wireless systems, (3) broadly applicable innovations in the instruction of students, and (4) a program of undergraduate research in communication theory.The two main architectures that are being considered for future high-speed wireless communication systems are a coded single-carrier system employing a decision feedback equalizer (DFE) at the receiver and a coded orthogonal frequency division multiplexing (OFDM) system. In this project, the problemof designing coded modulation for the OFDM system is being formally developed. By viewing this problem in the more general framework of frequency domain coded modulation (FDCM), design rules are being developed that lead to systems that can efficiently tradeoff complexity for improved bit error probability and amplifier efficiency relative to traditional OFDM systems. Furthermore, this project is analyzing the utility of the resulting systems as a hybrid between coded single-carrier systems employing a DFE and coded OFDM systems; this provides a unified comparison of the most widely considered system architectures for high-speed wireless communications. The educational portion of this project employs three complementary methods that strive to foster student learning through innovations that supplement traditional classroom instruction. The first method will be the continuation of theintroduction of supplements that support active learning in traditional courses, such as the introduction of games of chance for course points in an undergraduate probability class. The second method will be the development of a capstone wireless communications course that will allow graduate students and advanced undergraduates to integrate their knowledge in various communication system components in a team-oriented environment that stresses overall system performance. Finally, the third method will be the continuation of a funded undergraduate research program, which aids promising undergraduate engineers by providing one-on-one attention in an active research environment.