多媒体信源编码在增强现实领域的最新标准化研究进展

阐述了多媒体信源编码在增强现实领域的标准化研究进展,介绍了ISO/IEC JTC1 SC29所做MPEG系列标准在此方面的贡献,及可行的应用.     

COSET PARTITION OF ADDITIVE GROUPS AND MINORITY-LOGIC DECODING ALGORITHM FOR RM CODES

Two new notions for the coset partition of dyadic additive groups are proposed,andtheir sufficient and necessary conditions are also given.On the basis of these works,the feasibilityproblem of implementing minority-logic decoding algorithm for RM codes is solved.     

一种 1x2x4分布式空时编码异步协作方案

协作分集技术可以有效提高移动通信系统的容量和可靠性。近年来,分布式空时码（DSTC）被广泛应用到协作分集系统以实现空间分集增益。然而,时间异步和频率异步会使正交DSTC的码字结构受到破坏,严重影响系统性能。本文针对时间异步的协作通信系统,提出一种基于分布式Alamouti STBC的1x2x4异步协作方案。对这种方案进行了理论分析和算法推导,并且重新定义了中继节点归一化后的发射信号幅度。仿真结果表明该方案的误比特率性能具有明显优势,能在时间异步的协作通信系统中很好地发挥多天线接收性能。     

A multi-parametric programming approach for multilevel hierarchical and decentralised optimisation problems

In this paper, we outline the foundations of a general global optimisation strategy for the solution of multilevel hierarchical and general decentralised multilevel problems, based on our recent developments on multi-parametric programming and control theory. The core idea is to recast each optimisation subproblem, present in the hierarchy, as a multi-parametric programming problem, with parameters being the optimisation variables belonging to the remaining subproblems. This then transforms the multilevel problem into single-level linear/convex optimisation problems. For decentralised systems, where more than one optimisation problem is present at each level of the hierarchy, Nash equilibrium is considered. A three person dynamic optimisation problem is presented to illustrate the mathematical developments.     

城域WDM环网及其应用

文章阐述了城域WDM环网的节点结构、保护方式、波长转换器、子速率复用和光网络管理等,给出了WDM环网在城域应用时应考虑的一些因素,并分析了运营商所关心的系统成本问题。     

非线性等重码的一个上界

本文给出等重码的一个上界，并且举例说明这个上界是可以达到的，作为直接推论，我们推导出等重等距码的几个结果。     

基于LDPC编码的IDMA编码和扩频均衡研究

将一种接近容量限的码型低密度奇偶校验码(LDPC)应用于交织多址接入系统,即基于LDPC编码的IDMA系统;深入研究了与此系统相关的编码和扩频的均衡问题。在高斯白噪声(AWGN)信道中,在以不同码率编码的该系统中,分别以误比特率10-6和10-3为标准,根据要达到的可靠数据和语音通信所需要的最小信噪比(SNR),阐明编码和扩频的均衡问题。仿真结果表明,在AWGN信道中,对于可靠的通信传输服务,基于LDPC编码的IDMA系统传输的最佳LD-PC编码码率在0.4和0.5之间;并且,以这种码率传输的系统相对于其他系统的优势是相当明显的。     

浅析3G用户编号方案

在分析现行移动通信网和固定电话网用户编号方案的特点及存在问题的基础上,建议在第三代移动通信网中采用长途区号 3G用户号码的编号方案。     

宽带IP城域网及其应用

文章结合南京电信公众宽带IP城域网的建设，对宽带IP城域网的网络结构、用户接入安全、网络管理和认证计费作了阐述，并简要介绍了应用于宽带IP城域网上的一些业务。     

A fast iterative scheme for multilevel thresholding methods

The previously published optimal thresholding techniques based on some objective functions are very efficient in the bi-level thresholding case, but they are impractical when extended to multilevel thresholding. The reason for this is their computational complexity which grows exponentially with the number of thresholds. In this paper, an iterative scheme is proposed to render these optimal thresholding techniques more practical. The proposed algorithm starts with a bi-level thresholding, then uses the initial results to obtain higher-order thresholds. This algorithm is iterative and the convergence is proved. We also introduce some useful programming techniques to make the computation more efficient. The proposed algorithm can therefore determine the number of thresholds automatically as well as save a significant amount of computing time.