CIF: Small: Disparity of Coherence and Channel Information in Wireless Networks - Opportunities and Challenges

由于对无线频谱的需求不断增加，并且由于电路技术的不断改进，无线网络的性能极限以及有望接近这些极限的方法仍然是一个重要的研究主题。无线通信中的许多先进技术越来越依赖于在节点之间获取和适当交换的链路质量（信道状态信息）的知识。该任务密切依赖于相应信道增益变化的速度（相干间隔）。由于节点速度的变化或散射环境的差异，链路相干性间隔可能很容易不同，但链路相干性差异下的网络性能限制的基本特征迄今为止还没有得到。该项目利用了相干性差异暴露的额外自由度，从而提高了无线通信网络中的频谱效率。 该研究计划与旨在促进STEM领域包容性的教育推广活动紧密结合。该项目启动了对无线网络相干性差异影响的基础研究，解决无线网络的原型构建块，其在相干性差异下的性能限制，以及在这种情况下捕获收益的有效方法。该项目有以下主要组成部分：（1）研究相干视差下的广播信道和多址信道，包括多用户扩展和外边界;（2）研究相干视差下的频率选择性信道和正交频分复用（OFDM）资源重用;（3）研究相干视差下的中继和协作网络。

Due to the increasing demand on wireless spectrum and empowered by continued improvements in circuit technology, the performance limits of wireless networks as well as methods that hold the promise of approaching these limits remain a vital topic of inquiry. Many of the advanced techniques in wireless communication are increasingly dependent on the knowledge of link qualities (channel state information) being acquired and properly exchanged among the nodes. This task is closely dependent on how rapidly the corresponding channel gains vary (coherence intervals). Link coherence intervals may easily be different due to variations in node speeds or differences in scattering environment, but a fundamental characterization of the performance limits of networks under link coherence disparity has not been available thus far. This project exploits additional degrees of freedom that coherency disparity exposes, thus increasing spectral efficiency in wireless communication networks. The research plan is tightly coupled with educational outreach activities that seek to foster inclusiveness in STEM fields.This project initiates a fundamental study of the effects of coherence disparity on wireless networks, addressing prototype building blocks of wireless networks, their performance limits under coherence disparity, and efficient methods of capturing gains in this scenario. The project has the following main components: (1) Study of broadcast channels and multiple-access channels under coherence disparity, including multi-user extensions and outer bounds; (2) Study of frequency-selective channels and orthogonal frequency-division multiplex (OFDM) resource reuse under coherence disparity; and (3) Study of relay and cooperative networks under coherence disparity.