并行组合扩频非等概超宽带系统误码性能研究

基于并行组合扩频的超宽带通信系统,结合了并行组合扩频通信系统的高效通信能力和超宽带通信系统的良好保密性能,可以同时满足通信系统对高效性和安全性的要求。该系统中的并行组合扩频部分输出的信号具有非等概出现的特点,推导了在非等概情况下超宽带系统跳时M进制-脉冲幅度调制(time hopping M-arypulse amplitude modulation,TH M-PAM)方式的解调差错概率,并通过仿真验证了公式推导的正确性。在加性高斯白噪声信道条件下,建立系统仿真模型,对系统整体性能进行仿真。仿真结果表明,基于并行组合扩频的超宽带通信系统具有良好的误码性能,并且优于常规超宽带通信系统和基于连续波调制的并行组合扩频通信系统。

逼近信道容量的非等概幅度相移键控星座映射

为解决格雷编码的幅度相移键控(APSK:Amplitude Phase Shift Keying)映射方式在非迭代的独立解映射情况下互信息与信道容量仍存在差距的问题,提出一种非等概的APSK映射方式,通过减少内环对应的星座点数,变换为低价的Gray-PSK,从而提高其限制下的互信息。仿真结果表明,针对2/3码率设计的64NE-APSK较64Gray-QAM星座映射有0. 6 d B的性能优势,比64Gray-APSK的系统有约0. 1 d B的优势。从而,在接收端独立解映射的情况下,该设计能比格雷编码的APSK映射更逼近信道容量,且无需增加系统实现的复杂度。

Lyapunov Inequalities of Nonlinear Discrete Systems

In this paper, we study the nonlinear discrete systems and obtain several lyapunov inequalities for them. Then we give the application for lyapunov inequality.

Hardy-Type Inequalities on H-Type Groups andAnisotropic Heisenberg Groups

The author obtains some weighted Hardy-type inequalities on H-type groups and anisotropic Heisenberg groups. These inequalities generalize some recent results due to N. Garofalo, E. Lanconelli, I. Kombe and P. Niu et al.

An asymmetric Orlicz centroid inequality for probability measures

Using M-addition,an asymmetric Orlicz centroid inequality for absolutely continuous probability measures is established corresponding to Paouris and Pivovarov’s recent result on the symmetric case.As an application,we extend Haberl and Schuster’s asymmetric Lp centroid inequality from star bodies to compact sets.