Real Option—A New Approachin the Evaluation of TelecomInvest ment Projects

1IntroductionNowadays ,telecomindustry is facing many uncer-tainties ,because of which some carefully designed planshave to be completely renewed.It s a great challenge tous to adapt our work to the changing circumstances anddi minish the loss brought by various uncertainties .Option,by enabling the investor to control uncertainrisks at the expense of some cost can effectively li mitlosses and indefinitely increase the potential to grow.This is the most attractive feature of modern option,andf…     

亚太地区多媒体业务发展概况

本文介绍了与多媒体有关的业务近年来在亚太地区国家投资立项、开发、试验、标准化、网络互连等应用的情况，侧重于多媒体业务的工程实施，文中既举例讲述各国的发展动态，还按技术分类作了详细的进展介绍。     

基于业务等级的波长分配算法

本文主要研究在WDM全光通信网中,将业务等级约定(SLA)和路由波长分配(RWA)问题结合在一起考虑,根据实际网络情况,确保高等级业务得到更好的服务。本文从不同的角度考虑,提出了两种算法,并对其进行了仿真比较和分析。     

迅速崛起的亚太光纤市场

本文归纳分析出亚太光纤市场的两个显著特点，介绍了亚太地区光通信发展水平，以及亚太各国和地区间的光通信合作，指出亚太光纤市场得以迅速发展的主要原因。     

加速北京光纤数字同步网建设促进首都信息高速公路发展

本文首先回顾了北京地区PDH光纤传输网的情况,然后结合信息高速公路的发展,介绍了北京地区光纤数字同步网的建设和目前的设备配置。     

Design of 25 Gbit/s half-rate CDR with 1:2 demultiplexer for 100 GbE optical interconnects

A 25 Gbit/s clock and data recovery(CDR) circuit with 1:2 demultiplexer for 100 Gbit/s Ethernet(100 Gb E) optical interconnects has been designed and fabricated in Taiwan Semiconductor Manufacture Company(TSMC) 65 nm complementary metal-oxide-semiconductor(CMOS) technology. A novel quadrature voltage-controlled-oscillator(QVCO) structure adopts two pairs of transconductance cell and inverters to acquire rail-to-rail output swing. A half-rate bang-bang phase detector adopts four flip-flops array to sample the 25 Gbit/s input data and align the data phase, so the 25 Gbit/s data are retimed and demultiplexed into two paths 12.5 Gbit/s output data. Experimental results show that the recovered clock exhibits a peak-to-peak jitter of 7.39 ps and the recovered data presents a peak-to-peak jitter of 7.56 ps, in response to 312-1 pseudorandom bit sequence(PRBS) input. For 1.2 V voltage supply, the CDR circuit consumes 92 m W(excluding output buffers).     

Matched Filter Based Spectrum Sensing When Primary User Has Multiple Power Levels

In this paper,we investigate the matched filter based spectrum sensing in a more reasonable cognitive radio(CR) scenario when the primary user(PU) has more than one transmit power levels,as regulated in most standards,i.e.,IEEE 802.11 Series,GSM,LTE,LTE-A,etc.This new multiple primary transmit power(MPTP) scenario is specialized by two different targets:detecting the presence of PU and identifying the power level.Compared to the traditional binary sensing where only the presence of PU is checked,SU may attain more information about the primary network(making CR more "intelligent") and design the subsequent optimization strategy.The key technology is the multiple hypothesis testing as opposed to the traditional binary hypothesis testing.We discuss two situations under whether the channel phase is known or not,and we derive the closed form solutions for decision regions and several performance metrics,from which some interesting phenomenons are observed and the related discussions are presented.Numerical examples are provided to corroborate the proposed studies.     

第三代移动通信技术标准的演进

从关键技术、技术特点等方面对3G中WCDMA和cdma2000两种技术标准的演进路线进行了介绍。指出了在现 有移动通信系统的传输能力已经不能完全满足不断发展的移动数据业务的情况下,演进型3G技术的发展已 成为大势所趋。     

移动IPv6中通信主机绑定更新的安全策略

移动IPv6的安全策路是移动IPv6体系的一个重要组成部分。针对现有的移动IPv6安全策略,着重研究通信主 机绑定更新过程的安全性。通过对主机绑定更新过程的分析,指出其存在的安全隐患,并针对移动主机可能 受到拒绝服务攻击的问题提出相应的改进策略,提高通信主机绑定更新过程的安全性。     

南京ATM宽带多媒体网络的建设

ＡＴＭ技术在经济ＩＴＵ－Ｔ和ＡＴＭ论坛多年的研究与论证后,已开始在多个领域得到广泛运用。本文介绍了南京市ＡＴＭ的网络的建设情况,包括基本组成、网络业务及网络的测试等。