下一代无线通信系统中的全分集空时分组编码技术

Motivated by the huge demands for fast and reliable communications over wireless channels, future wireless communication systems should support higher data rate and more reliable performance. Multiple-input and multiple-output (MIMO) systems have emerged as one of the most significant breakthroughs in future wireless communications, since the multiple antennas can be utilized to increase the transmission rate through multiplexing and improve the reception performance through diversity. To explore the diversity advantage, space-time block coding (STBC) can maximize the spatial diversity and thereby improve the transmission reliability, which has been widely acknowledged as a hot research topic in the MIMO systems. Very recently, there are two interesting and challenging problems in space-time coded MIMO systems: how to well address the tradeoff between code rate and decoding complexity in MIMO point-to-point systems and how to achieve full diversity in MIMO wireless networks. In this project, we will focus on the STBC designs in MIMO point-to-point systems and multiuser wireless networks. At the receiver side, partial interference cancellation group decoding will be utilized to realize the fast decoding in point-to-point systems and group zero-forcing (ZF) receiver is applied to suppress the inter-user interference in wireless networks. The aim of this project is to improve the transmission reliability in future wireless communications by proposing the full-diversity STBC designs with high code rate and low decoding complexity.

为了满足人们对快速和可靠通信的巨大需求，下一代无线通信系统需要提供更高的输出速率和更可靠的性能。多天线技术是下一代无线通信系统中关键技术之一，因为它能显著提高无线通信的容量和性能。空时分组编码技术能够最大化空间分集增益，从而提高信号传输的可靠性，是当前多天线技术中的研究热点。如何解决多天线点对点系统中的码率和解码复杂度的折中问题，以及利用空时编码去获得多天线无线网络中的全分集增益，是下一代无线通信系统中需要解决的重要问题。本项目以空时编码技术为研究对象，分别研究多天线点对点和多用户无线网络的系统模型，采用部分干扰消除分组解码技术去实现点对点系统中的快速解码，同时采用分组迫零技术去实现无线网络中用户间的干扰消除，目标是设计高码率和低解码复杂度的空时编码，用来最大化不同系统中的分集增益，从而提高下一代无线通信系统中信号传输的可靠性。

多天线技术是下一代无线通信系统中关键技术之一，因为它能显著提高无线通信的容量和性能。空时分组编码技术能够最大化空间分集增益，从而提高信号传输的可靠性，是当前多天线技术中的研究热点。在本项目的资助下，项目组对空时分组编码技术的理论基础展开了深入的研究，扩展了空时分组编码技术的理论应用场景。其中，我们实现了空时分组编码技术在基于波束形成技术的多用户多天线系统中的应用，具体表现在多路广播信道中基于空时分组编码的波束形成技术；通过物理层网络编码的最优设计，优化了空时分组编码技术在多用户多天线无线协作通信中的解码性能和码率，具体表现在空时编码技术在基于计算转发的多用户通信系统中的应用；通过信道编码技术，进一步提高了多用户系统中的解码性能。在本项目支持下，项目组共发表4篇IEEE期刊论文（包括一篇IEEE Transactions on Information Theory）和一篇IEEE的旗帜会议论文（ICC）。