Quantum Stream Cipher Based on Holevo–Yuen Theory

In this review paper, we first introduce the basic concept of quantum computer-resistant cryptography, which is the cornerstone of security technology for the network of a new era. Then, we will describe the positioning of mathematical cryptography and quantum cryptography, that are currently being researched and developed. Quantum cryptography includes QKD and quantum stream cipher, but we point out that the latter is expected as the core technology of next-generation communication systems. Various ideas have been proposed for QKD quantum cryptography, but most of them use a single-photon or similar signal. Then, although such technologies are applicable to special situations, these methods still have several difficulties to provide functions that surpass conventional technologies for social systems in the real environment. Thus, the quantum stream cipher has come to be expected as one promising countermeasure, which artificially creates quantum properties using special modulation techniques based on the macroscopic coherent state. In addition, it has the possibility to provide superior security performance than one-time pad cipher. Finally, we introduce detailed research activity aimed at putting the quantum stream cipher into practical use in social network technology.     

Error Performance of Amplitude Shift Keying-Type Asymmetric Quantum Communication Systems

We propose an amplitude shift keying-type asymmetric quantum communication (AQC) system that uses an entangled state. As a first step toward development of this system, we evaluated and considered the communication performance of the proposed receiver when applied to the AQC system using a two-mode squeezed vacuum state (TSVS), the maximum quasi-Bell state, and the non-maximum quasi-Bell state, along with an asymmetric classical communication (ACC) system using the coherent state. Specifically, we derived an analytical expression for the error probability of the AQC system using the quasi-Bell state. Comparison of the error probabilities of the ACC system and the AQC systems when using the TSVS and the quasi-Bell state shows that the AQC system using the quasi-Bell state offers a clear performance advantage under specific conditions. Additionally, it was clarified that there are cases where the universal lower bound on the error probability for the AQC system was almost achieved when using the quasi-Bell state, unlike the case in which the TSVS was used.     

一种改进的短波链路数据传输协议

因特网的迅猛发展,使得IP协议成为事实上的工业标准,各种无线网络也纷纷开始使用IP技术组网,短波IP网络也已经出现。在短波链路上传输IP报文通常采用ARQ模式,以对网络层提供报文的无错传输。目前ARQ传输协议普遍采用选择式重发策略,在数据帧中加入帧序号,以确保收方能对数据帧重新排序。为提高IP报文在短波链路上的传输效率,对现有的短波链路选择式重发ARQ协议进行了分析,针对收发双方的通信流程进行了改进,提出了一种无帧序号的ARQ传输协议。测试结果表明,在同样的信道状况下,改进后的协议吞吐率性能有了一定的提高。最后就如何进一步提高该协议性能进行了思考。     

移动通信终端多媒体系统设计

采用中星微VC0858在CDMA移动通信终端开发平台上实现了多媒体系统,详细介绍了硬件结构和软件系统的设计.测试结果证明该方案符合移动通信终端实际使用要求.     

无人值守通信机房电源系统安全维护策略

随着设备智能化发展和人工成本提升,通信机房无人值守化成为必然趋势.通信机房电源系统作为动力之源,确保电源系统安全成为维护人员关注重中之重,也是无人值守化的基本保证.制定合理的电源系统安全维护策略,直接决定无人值守通信机房的可靠运行和通信畅通.因此,文章分析了通信机房电源系统各组成部分的特点,提出了需要采用的技术措施和可...     

融合通信相关标准进展及其业务实现的关键技术

本文先介绍了融合通信的标准进展情况,然后概括了其3种基本产品形态及主要企业的相关产品,最后分析了实现融合通信产品的主要技术现状和发展趋势.     

统一通信在商务领航平台上的实现

电信现网上分布着各种通信能力,在互联网上也分布多种通信能力,本文说明了如何将这些分布的通信能力进行融合,提供跨运营商、跨网络架构、跨业务平台、面向客户的统一通信业务,介绍了存商务领航企业信息化平台上的具体实现,分析了业务实现中难点和主要技术.     

基于GIS的移动通信基站管理系统

使用VB.Net和Mapinfo的MapX组件,结合SQL Server2000数据库,实现了移动通信基站的可视化管理。将移动基站分布信息、呼叫信息、切换信息等在电子地图上以不同的视图标示,为移动基站网络建设的优化配置提供一定的支持,也使运维人员对系统的管理和维护更加直观。     

基于ADuC841的水泥回转窑旋风筒控制系统设计

本文介绍了基于ADuC841的水泥回转窑旋风预热器控制系统的设计.该系统通过在旋风筒中安装各种传感器实时监控筒内的风量、风速、温度等状态,同时应用可控硅技术对旋风预热器中风机进行控制,得到所需要的理想风量,使得能更充分的利用水泥回转窑的尾气热能,同时也能减少水泥回转窑污染废气排放,利于环保要求.上位机采用图形化编程语言LabVIEW实现,界面友好,用户使用方便.模拟实验与现场运行验证了设计的有效性.     

多用户MIMO系统中一种基于一位反馈信息的调度算法

针对多用户MIMO(Multiple-Input Multiple-Output)无线通信系统潜在的多用户分集增益,该文提出了一种基于一位反馈信息的多用户调度算法.理论分析表明,设置合理的门限可以从统计意义上最大化系统平均频谱效率.同时,该文从理论上对最优门限的选择进行了分析.仿真结果表明所提算法可有效利用多用户分集来提高系统的频谱性能.