Turbo Like Codes for Distributed Source and Joint Source-Channel Coding of Correlated Sources

0311014特拉华州的哈维尔·加西亚-弗里亚苏这项研究涉及到对由多个源组成的通信系统的研究，这些通信系统传输相关的信息。最终目标是利用源之间的相关性来减少总传输能量。这项研究中开发的技术可能会对传感器网络领域产生广泛的影响，使开发需要较少传输功率的传感器成为可能。例如，可能的应用是开发低功耗-侵入性的生物传感器。为了减少总传输能量，研究将集中于类Turbo码的应用，特别是具有低密度生成矩阵的线性码的应用，以使大范围的多终端相关源(离散或连续的，有或无记忆的)的压缩比接近理论极限，以及ii)对大范围的多终端相关源和不同的信道环境执行联合信源-信道编码。所提出的系统具有编码端简单的特点。这种简单性便于在实际应用中实现所提出的方案。此外，编码过程对于每个信源是完全独立的，并且它不需要关于相关性模型或信源统计的知识，这在传感器网络和图像/视频压缩等实际应用中是非常感兴趣的。为了获得接近信源和联合信源-信道编码的理论极限的性能，解码器以自适应的方式估计和利用信源的统计信息。

0311014Javier Garcia-FriasU of DelawareThis research involves the study of communications systems consisting of multiple sources transmitting correlated information. The final objective is to exploit the correlation among the sources to reducethe total transmitted energy. The techniques developed in this research may have a broad impact in the area of sensor networks, making it possible to develop sensors requiring less transmitted power. For example, a possible applications could be the development of less-power-invasive biosensors.In order to reduce the total transmitted energy, the research will focus on the application of turbo-like codes, and specifically of linear codes with low-density generator matrix to i) achieve compression rates close to theoretical limits for a wide range of multi-terminal correlated sources (discrete or continuous, with and without memory) and ii) perform joint source-channel coding for a wide range of multi-terminal correlated sources and different channel environments. The proposed system is characterized by its simplicity at the encoder site. This simplicity facilitates the implementation of the proposed scheme in practicalapplications. Moreover, the encoding process is completely independent for each source, and it does not require knowledge about the correlation model or source statistics, which is of great interest in practicalapplications such as sensor networks and image/video compression. In order to achieve a performance close to the theoretical limits for source and joint source-channel coding, the statistics of the sourcesare estimated and exploited at the decoder in an adaptive fashion.