在假设信道为连续平坦衰落的条件下,提出两种基于重构观测样本的MIMO信道估计方法,一种是基于累加观测样本序列AONSS(Accumulative Observed Noisy Signal Sequence)的方法,另一种是基于级联观测样本序列CONSS(Reconnected Obserred Noi...在假设信道为连续平坦衰落的条件下,提出两种基于重构观测样本的MIMO信道估计方法,一种是基于累加观测样本序列AONSS(Accumulative Observed Noisy Signal Sequence)的方法,另一种是基于级联观测样本序列CONSS(Reconnected Obserred Noisy signal Sequence)的方法。仿真结果表明:在信道时变情况下,本文提出的基于重构观测样本的信道估计方法是切实可行的,为深入研究MIMO通信系统下的基于重构观测样本的信道估计提供了一种新的思路和途径。展开更多
通信传输一方面需要足够的传输容量,能完成数据传输的任务;另一方面又要考虑通信安全,保证敏感信息不会被截获。针对通信传输过程中波形相关特征容易被利用的问题,分析了标准正交频分复用(orthogonal frequency division multiplexing,O...通信传输一方面需要足够的传输容量,能完成数据传输的任务;另一方面又要考虑通信安全,保证敏感信息不会被截获。针对通信传输过程中波形相关特征容易被利用的问题,分析了标准正交频分复用(orthogonal frequency division multiplexing,OFDM)波形存在的缺陷,提出一种抗侦收的下行传输波形设计方法。该方法采用两层级联生成的混沌序列作为训练序列,传输波形中不使用循环前缀(cyclic prefix,CP),并且在接收端使用干扰迭代消除的方法抵消干扰。对信号波形仿真分析,结果表明无循环前缀的方法误码率接近有循环前缀的OFDM无线通信系统,并且新构造的波形无法使用基于相关运算的方法进行参数估计。展开更多
We discuss an object from algebraic topology,Hopf invariant,and reinterpret it in terms of the φ-mappingtopological current theory.The main purpose of this paper is to present a new theoretical framework,which can di...We discuss an object from algebraic topology,Hopf invariant,and reinterpret it in terms of the φ-mappingtopological current theory.The main purpose of this paper is to present a new theoretical framework,which can directlygive the relationship between Hopf invariant and the linking numbers of the higher dimensional submanifolds of Euclideanspace R^(2n-1).For the sake of this purpose we introduce a topological tensor current,which can naturally deduce the(n-1)-dimensional topological defect in R^(2n-1) space.If these (n-1)-dimensional topological defects are closed orientedsubmanifolds of R^(2n-1),they are just the (n-1)-dimensional knots.The linking number of these knots is well defined.Using the inner structure of the topological tensor current,the relationship between Hopf invariant and the linkingnumbers of the higher-dimensional knots can be constructed.展开更多
文摘在假设信道为连续平坦衰落的条件下,提出两种基于重构观测样本的MIMO信道估计方法,一种是基于累加观测样本序列AONSS(Accumulative Observed Noisy Signal Sequence)的方法,另一种是基于级联观测样本序列CONSS(Reconnected Obserred Noisy signal Sequence)的方法。仿真结果表明:在信道时变情况下,本文提出的基于重构观测样本的信道估计方法是切实可行的,为深入研究MIMO通信系统下的基于重构观测样本的信道估计提供了一种新的思路和途径。
文摘通信传输一方面需要足够的传输容量,能完成数据传输的任务;另一方面又要考虑通信安全,保证敏感信息不会被截获。针对通信传输过程中波形相关特征容易被利用的问题,分析了标准正交频分复用(orthogonal frequency division multiplexing,OFDM)波形存在的缺陷,提出一种抗侦收的下行传输波形设计方法。该方法采用两层级联生成的混沌序列作为训练序列,传输波形中不使用循环前缀(cyclic prefix,CP),并且在接收端使用干扰迭代消除的方法抵消干扰。对信号波形仿真分析,结果表明无循环前缀的方法误码率接近有循环前缀的OFDM无线通信系统,并且新构造的波形无法使用基于相关运算的方法进行参数估计。
基金National Natural Science Foundation of China and Cuiying Project of Lanzhou University
文摘We discuss an object from algebraic topology,Hopf invariant,and reinterpret it in terms of the φ-mappingtopological current theory.The main purpose of this paper is to present a new theoretical framework,which can directlygive the relationship between Hopf invariant and the linking numbers of the higher dimensional submanifolds of Euclideanspace R^(2n-1).For the sake of this purpose we introduce a topological tensor current,which can naturally deduce the(n-1)-dimensional topological defect in R^(2n-1) space.If these (n-1)-dimensional topological defects are closed orientedsubmanifolds of R^(2n-1),they are just the (n-1)-dimensional knots.The linking number of these knots is well defined.Using the inner structure of the topological tensor current,the relationship between Hopf invariant and the linkingnumbers of the higher-dimensional knots can be constructed.
