【作者】 郑武；

【导师】 刘兴钊； 宋文涛；

【作者基本信息】 上海交通大学 ， 信号与信息处理， 2007， 博士

【摘要】 近年来,移动通信技术和市场飞速发展。在新技术和市场需求的共同作用下,人们开始着手对下一代移动通信系统进行研究。下一代移动通信系统期望能提供更高的数据传输率、更好的通信质量、支持更快的终端移动速度,由多发射和多接收天线组成的多输入多输出(Multiple Input Multiple Output,简称MIMO)技术是达到上述目标的有效手段。它可以在不牺牲带宽和不增加发射功率的情况下成倍地提高信道容量,获得了单天线系统所无法比拟的容量。所以,MIMO技术成为下一代移动通信系统所必须采纳的关键技术之一。在发射端不具备信道状态信息的情况下,空时编码可以充分挖掘MIMO系统的容量潜力,极大地提高信息传输速率和改善传输质量。为了获取接近MIMO容量极限的性能,常常还必须依赖于信道编码技术来有效地对抗干扰、噪声和衰落。因此将两者结合起来,进行合理的设计以解决高速数据传输和可靠数据传输之间的矛盾;进行联合检测/译码算法的研究,以解决高性能和低复杂度之间的矛盾,均成为重要的研究方向。本文首先研究了信道编码和空时编码的联合检测/译码问题。根据“Turbo处理”原则,将上述两个模块进行串行级联,并在接收端进行迭代检测/译码,是折中检测性能和计算复杂度的有效手段;其中基于MAP准则的软输入软输出的空时检测算法是实现的难点,也是保证优良性能的关键所在。本文在充分研究基于MMSE准则的软干扰消除、候选集符号球检测和迭代树搜索(ITS)检测的基本算法和复杂度的基础上,提出了2种高性能低复杂度的检测算法。基于MMSE准则的可重置迭代树搜索检测(IRTS)算法在首次迭代时,通过MMSE准则来计算各个符号的可靠度,以此来重新配置树结构,进行迭代检测。同ITS算法相比,仅仅引入了较低的计算复杂度增加,而使得性能有了较大的改善。将IRTS(MMSE)算法进一步简化,忽略其中噪声的影响,得到了基于ZF准则的IRTS算法,其性能介于IRTS(MMSE)和更多还原

【Abstract】 Mobile technologies and markets have developed very quickly. Driven by new technologies and market demands, the research on next generation mobile communication systems have been launched on. The next generation mobile communication systems are expected to provide higher transmission rate, offer better quality and support faster moving terminals. Multiple-input multiple-output (MIMO) technology, deploying by multiple transmit and receive antennas, is an effective way to achieve the above objectives.Without increasing bandwidth or transmit power MIMO systems can improve channel capacity greatly, which is much lager than single antenna systems. Therefore, MIMO technology have become one of the key techniques adopted in the next generation mobile communication systems. Space-time code can make full use of MIMO channel capacity to increase rate and improve performance in case there is no channel state information (CSI) at the transmitter. To approach the performance of MIMO channel capacity, channel code is usually employed to combat interference, noise and fading. Thus by combining space-time code and channel code, the design and implementation is an important research direction, for example, for system design how to settle the conflict between high transmit rate and good performance; for joint space-time detector/channel decoder how to settle the conflict between high performance and low complexity.The issue of how to realize joint space-time detector/channel decoder is firstly investigated. To avoid the exponential complexity with the length of information bit sequence when using maximum likelihood (ML) detection, introducing an interleaver between the former two modules based on“Turbo Processing”principle, a serially concatenated system is formed and iterative detector/decoder is employed, which is an effective means for tradeoff between performance and complexity. Soft-in soft-out更多还原