Efficient Transmission Techniques for Digital Mobile Cellular and Digital Broadcast Applications

该项目有三个具体的研究领域： 基于均衡器的均衡，通过 从嵌入的训练数据导出的信道表征; 码分多址的干扰抑制，远近 以及码间干扰和来自不同用户的干扰; 用于广播传输的多载波方法 随时间变化的衰落效应。 研究的重点是 时变多径数据信道。 在相对较低的数据速率下， 无线通信信道的时变特性通常 导致在少量符号间隔上的信道变化。 在这种情况下，可以嵌入大量的训练数据 以使得能够进行调整 在接收器。 另一种选择，也许是迫于需要， 更高的数据速率，是为了增加传输的带宽 信号了则信道变化的相对速率较小 与符号率相比，训练的分数是 降低 随着使用更宽的带宽，多径效应变得 更重要和更复杂的接收器结构需要 被利用本研究对窄带和宽带都进行了研究 传输，用于数字蜂窝无线电和 数字广播频道

This project has three specific areas of study: Efficient Channel-Based Equalization, the computation of the equalizer via channel characterization derived from embedded training data; Interference Rejection for Code-Division Multiple Access, near-far and intersymbol interference and interference from disparate users; and Multicarrier Methods for Broadcast Transmission, for mitigation of time-varying fading effects. The focus of the study is on the time-varying multipath data channel. At relatively low data rates, the time-varying nature of wireless communication channels often leads to channel variation over a small number of symbol intervals. In this case a significant amount of training data can be embedded in the transmitted packets of data to enable adjustments to be made at the receiver. An alternative, perhaps forced by the need for higher data rates, is to increase the bandwidth of the transmitted signal. Then the relative rate of channel variation is less compared to the symbol rate, and the fraction of training is reduced. As wider bandwidths are used, multipath effects become more important and more sophisticated receiver structures need to be used. The research studies both narrow and wideband transmission, for applications in digital cellular radio and digital broadcast channels.