Robust Codes for Space-Time Communication, Iterative Decoding, and Multi-Rate Broadcast

用于时空通信、迭代解码和多速率广播的鲁棒代码

• 批准号: 0209110
• 负责人: Richard Wesel
• 金额: $ 24万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0209110&HistoricalAwards=false
• 关键词: Robust; Codes; Space; Time; Communication

The primary goal of this research is to produce practical codes that provideunequaled robustness, approaching the performance predicted by compoundchannel information theory for linear Gaussian channels. The resultingchannel codes will find application in many scenarios including wired andwireless broadcast, wireless local area networks, asymmetric digitalsubscriber lines, military anti-jam communications, and frequency hoppedcommunications.Results from compound channel information theory state that a single codeexists that supports communication over every channel that has a mutualinformation above the information rate of the code. Thus, once thetransmitter power spectrum is fixed, a code need not be specialized to aparticular frequency selective channel in a single antenna system or aparticular space-time path-gain matrix in a multiple antenna system. Whilethis theoretical result is more that thirty years old, practical code designhas focused to date on a weaker notion of robustness, that of averageperformance according to a statistical channel model, such as Rayleighfading. The power of the code design approach taken in thisresearch is that the code design is independent of statistical assumptionsabout the channel. The code simply works on every channel that it possiblycould.A second goal of this research is to develop codes that support multiplerates to different users. Here again, information theory (this timeinformation theory for degraded broadcast channels) lays out the limits ofperformance. Our research will closely approach these performance limits byapplying turbo codes to the concept of superposition coding for the degradedbroadcast channel.

这项研究的主要目标是产生实用的编码，提供无与伦比的稳健性，接近线性高斯信道的复合信道信息理论预测的性能。所得到的信道码将在许多场景中得到应用，包括有线和无线广播、无线局域网、非对称数字用户线、军事抗扰通信和跳频通信。复合信道信息理论的结果表明，存在一个单一的码，它支持在每个具有高于码的信息率的共同信息的信道上进行通信。因此，一旦发射机功率谱固定，就不需要专门针对单天线系统中的特定频率选择性信道或多天线系统中的特定空时路径增益矩阵。虽然这一理论结果已经有30多年的历史了，但到目前为止，实用的代码设计一直专注于较弱的稳健性概念，即根据统计信道模型的平均性能，例如瑞利衰落。本研究中所采用的编码设计方法的强大之处在于，编码设计独立于关于信道的统计假设。这项研究的第二个目标是开发支持对不同用户进行多路复用的代码。在这里，信息论(这一次是针对降级广播频道的信息论)列出了性能的限制。我们的研究将通过将Turbo码应用于降级广播信道的叠加编码概念来接近这些性能极限。