| 1. | Precise simulation model design of ofdm systems working under time - varying dispersive channel
系统在时变色散信道中的精确建模与仿真 |
| 2. | Secondly , detection of two important dispersive channels was studied in theory and from experiment
其次从理论和实验两方面系统地研究了两个常见畸变信道的信号检测。 |
| 3. | Ofdm , with the advantage of high spectrum efficiency and easy realization , can strongly combat multi - path and dispersive channel interference , so its application is remarkable in recent years
正交频分复用( ofdm )技术具有抗多径时延、抗信道衰落、频谱利用率高、硬件实现简单等优点，近年来受到广泛关注。 |
| 4. | In wireless and mobile communications , blind equalization and identification of dispersive channels is a very hot research topic recently , and it is especially a technical difficulty to identify and equalize the time - varying ( tv ) dispersive channels blindly
在无线和移动通信中，色散信道的盲均衡和盲辨识技术是当前国际上的研究热点，而时变色散信道的盲均衡与盲辨识问题更是其中的技术难点。 |
| 5. | Then this new model is disscused in detail and is extended to some more common tv dispersive channels . in the following chapter 5 , we do much effort to research the methods of blind equalization and identification of tv dispersive channels based on the proposed dt canonical model
首先对间接盲均衡方法，提出了对时不变信道矩阵的子空间营辨识算涪和可以消除误差传播效应的两级盲辨识算法，然后给出了一种直接盲均衡方法。 |
| 6. | The very recent results of blind equalization and identification of the tv dispersive channels in wireless communications are reviewed at first in detail , the drawbacks of them are pointed out and the basic idea overcoming them are suggested , which is the motivation of this thesis
论文首先回顾了目前时变色散信道的盲均衡与盲辨识技术的研究进展，指出了其中存在的问题和解决的思路，从而指明了本论文研究的动机和出发点。 |
| 7. | Firstly , a new joint filterbank precoders and decision feedback equalizers structure is proposed , and the corresponding optimization result based on the maximal mutual information criterion is derived . secondly , the concept of dt canonical model is proposed , which is very suitable for the task of blind signal processing based on the second - order statistical of the observations . thirdly , the methods of blind equalization and identification of the tv dispersive channels are researched systematically based on the proposed dt canonical model , and a subspace blind identification algorithm of the time - invariant channel matrix is developed
本文创新性的成果在于：提出了预编码-判决反馈联合均衡系统结构，并从理论推导得出了对应的最大互信息量最优化设计结果；首次提出了时变色散信道的离散正则模型概念，该模型适宜于利用观察数据的二阶统计量进行盲信号处理；基于离散正则模型对时变色散信道进行了系统的盲均衡和盲辨识方法研究，提出了对时不变信道矩阵的子空间盲辨识算法；针对误差传播效应问题，提出了可以消除误差传播效应的两级盲辨识算法；提出了基于离散正则模型的直接盲均衡算法；提出了基于特征恢复思想的神经网络直接自适应盲均衡算法。 |
| 8. | According to wireless and mobile communication system ' s background , this thesis study on estimation of time - varying dispersive channel from four respects : ( 1 ) aid of pilots , ( 2 ) cyclic prefix ( cp ) , ( 3 ) blind method , and ( 4 ) ofdm system with multiple transmitting antenna , in which the typical ways is decision - feedback algorithm and self - adaptive block algorithm
本文以无线和移动通信系统为背景，从四个方面对时变色散信道下的ofdm系统的信道估计和均衡问题进行了研究。第一是基于导频符号的信道估计方法，第二是基于循环前缀的信道估计方法，第三是信道的盲估计方法，第四是基于多天线ofdm系统的信道估计和均衡方法的研究。 |
| 9. | This method can convert the dispersive channels into independent flat fading subchannels , so that it increase the diversity gain of the receiver and outperform that of the original paper as for the ber performance and maximum mutual information while maintaining all the advantages of it . in chapter 4 , the models of the tv dispersive channels are reviewed in signal processing perspective
在第四章中，作者对时变色散信道的信号处理模型进行了研究，提出了离散正则模型的概念，对其进行了详细的讨论，并利用多采样率理论将该模型推广到一般的时变色散信道。 |
| 10. | Because of enabling to provide high - rate and high - quality wireless and mobile communication service , orthogonal frequency division multiplexing ( ofdm ) system is becoming a very hot research topic recently , and it is especially one of the technical difficulties to estimate and equalize the time - varying ( tv ) dispersive channels
在移动无线通信中，由于能提供高速率和高质量的通信服务，正交频分复用( ofdm )技术成为当前国际上的研究热点，而时变色散信道的估计和均衡问题是其中的技术难点之一。 |
