DECT技术在军事通信中的应用

DECT作为一种成熟的无绳电话标准已经得到广泛的应用,同时DECT也是一种方便的无线接入手段,可以与现有的多种系统互联。文章旨在讨论DECT技术如何应用于军事通信领域。     

简讯

Web2．0作为互联网的新潮流,无疑已经席卷了全球。为更好地响应市场发展．全面提升用户的体验,日前,D-Link宣布正式推出基于Web 2．0核心理念的D-Link 2．0新一代网络应用服务平台——mydlink及这一新平台中的第一款产品：DPH-300 VolP/DECT无线网络电话机。     

NETGEAR推出新型双模DECT无绳电话

近日，全球成长型商用网络专家与无线网络先锋美国网件（NETGEAR），宣布推出公司第一款同时支持传统陆地电话呼叫和Skype呼叫的双模DECT无绳电话。NETGEAR双模无绳Skype电话（SPH200D）产品包括一部手机和一台基站。基站同时连接在用户的家庭网络路由器和电话线插座上，使用户无需连接在计算机上就可以用一部无绳手机拔打和接收传统电话呼叫和Skype的呼叫。     

基于Mobile IP的数字增强型无绳电话系统

数字增强型无绳电话(Digital Enhanced Cordless Telephone)系统可以直接接入Internet，但这种互联并不足以让用户大范围漫游，因为Internet是基于网际协议IP的，该协议并不支持主机在不同子网间移动。利用移动IP就可以支持用户在不同子网间漫游。给出了一个基于移动IP的DECT系统设计方案，并讨论了移动IP与DECT之间的交互工作。     

近距离无线技术的介绍和对比

目前使用较广泛的近距无线通信技术是蓝牙（Bluetooth）,无线局域网802.11（Wi-Fi）和红外数据传输（IrDA）。同时还有一些具有发展潜力的近距离无线技术标准,它们分别是：Zigbee、超宽频（Ultra WideBand）、短距通信NFC、WiMedia、GPS、DECT、无线1394和专用无线系统等。     

DECT通信软件的设计与实现

DECT是欧洲无绳电话的标准，主要用于语音和数据通讯。阐述了该通信软件中的手持机方软件的设计原则和实现轮廓，包括各个协议层的实现思想和方法、处理机控制部分的设计、内存分配的设计原则以及底层驱动的设计应该注意的场合，最后对该嵌入式软件涉及的所需大量软件定时器的设计做了说明。     

双模Skype电话——NETGEAR SPH200D

近日,美国网件(NETGEAR)宣布推出公司第一款同时支持传统陆地电话呼叫和Skype呼叫的双模DECT无绳电话——SPH200D。NETGEAR双模无绳Skype电话产品内包括一部手机和一台基站。基站同时连接在用户的家庭网络路由器和电话线插座上,使用户无需连接在计算机上     

1.9GHz低电压低功耗CMOS射频低噪声放大器的设计

针对1.9GHzPHS和DECT无线接入系统的应用,提出了一种可工作于0.9V低电压的CMOS射频低噪声放大器,并对其电路结构、噪声及线性度等主要性能进行分析。该电路基于传统的折叠结构低噪声放大器,利用晶体管线性补偿技术,实现了低压低功耗下的高线性度。采用TSMC 0.18μm CMOS工艺模型设计与验证。     

日本数字无绳电话的发展概况

日本的PHS(Personal Handy Phone System)和欧洲的DECT(Digital European Cordless Telecommunication)、美国的VDPC系统、瑞典的CT3系统以及加拿大的CT2~ 系统都是继CT2之后的新一代数字无绳电话。它们具有双向呼叫、越区切换、位置登记以及漫游等功能,而且投资少、费用低,有着广阔的发展前景。论文试从概况、发展现状、用户预测等方面介绍日本的PHS。     

FoxPro2.5forDOS编程应注意的一个问题

FoxPro 2.5深受广大编程人员的喜爱,尤其是在菜单设计方面的强大功能,使编程人员摆脱了界面设计的复杂性,能轻而易举地设计出各种友好的界面。但笔者最近使用FoxPro2.5 for DOS的下拉弹出式菜单设计一个界面时,却遇到了一个小小的麻烦。请看下面的数据库与程序: 药品字典库(DECT.DBF)结构为:     

Kann man mit DECT noch vertraulich telefonieren?

Nachdem Sicherheitslücken im veralteten DECT-Standards bereits auf dem CCC-Kongress im Dezember 2008 erkennbar wurden, pr?sentierten die Autoren dieses Jahr eine Kryptoanalyse der DECT Verschlüsselung. Der Beitrag illustriert die derzeitige durch DECT verschuldete Bedrohungslage und gibt Handlungsempfehlungen zum sicheren Telefonieren.     

Wideband mobile antenna design based on artificial neural network models

A compact wideband planar monopole antenna is designed and optimized based on artificial neural network (ANN) models. The antenna is suitable for DCS, PCS, DECT, PHS, IMT‐2000, UMTS, and WLAN in mobile communication. The design time decreases dramatically due to using the ANN models. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13: 316–320, 2003.     

Surface extraction from multi-material components for metrology using dual energy CT

This paper describes a novel method for creating surface models of multi-material components using dual energy computed tomography (DECT). The application scenario is metrology and dimensional measurement in industrial high resolution 3D x-ray computed tomography (3DCT). Based on the dual source / dual exposure technology this method employs 3DCT scans of a high precision micro-focus and a high energy macro-focus x-ray source. The presented work makes use of the advantages of dual x-ray exposure technology in order to facilitate dimensional measurements of multi-material components with high density material within low density material. We propose a workflow which uses image fusion and local surface extraction techniques: a prefiltering step reduces noise inherent in the data. For image fusion the datasets have to be registered. In the fusion step the benefits of both scans are combined. The structure of the specimen is taken from the low precision, blurry, high energy dataset while the sharp edges are adopted and fused into the resulting image from the high precision, crisp, low energy dataset. In the final step a reliable surface model is extracted from the fused dataset using a local adaptive technique. The major contribution of this paper is the development of a specific workflow for dimensional measurements of multi-material industrial components, which takes two x-ray CT datasets with complementary strengths and weaknesses into account. The performance of the workflow is discussed using a test specimen as well as two real world industrial parts. As result, a significant improvement in overall measurement precision, surface geometry and mean deviation to reference measurement compared to single exposure scans was facilitated.     

Heterogeneous system level co-simulation for the design of telecommunication systems

The advanced complexity and heterogeneity of modern telecommunication systems mostly lead to the incorporation of heterogeneous implementation technologies and design styles. Consequently, the design representation of such systems often requires the mixed use of distinct model of computations at different abstraction layers. Therefore, heterogeneous co-simulation is needed in order to enable the effective communication and interaction among the involved models of computation. This paper resolves this issue by proposing the heterogeneous co-modelling of telecom systems based on the combination of SDL semantics with C language running on an instruction set simulator, coupling in that way the specification and the first refinement steps of the co-design flow. The missing test link between the corresponding tools that support the SDL-C co-model is addressed by proposing a heterogeneous co-simulation scheme through the development of a mediator. Finally, the proposed methodology and the efficiency of the built environment are evaluated through a case study associated with the design of the MAC layer of the DECT telecom system.^1,2     

Integration | Innovation | Inclusion: Values,Variables and the Design of Human Environments

Complexity, complication, contradiction, consumption, confusion, delusion, depression. Opportunity, inspiration, ingenuity, compassion, wisdom. Our world is perplexing, our times are fast moving, and our choices are many. To find an appropriate path is a daunting yet vital challenge that confronts us as individuals, as communities, and as a civilization. How sustainable is our world? How reasonable are our behaviors? The present article is a collection of thoughts on a series of intertwined issues related to the contemporary world, its environmental dimensions, and their present-day problems. The goal is to survey the landscape through a lens of Environmental Design, to provide some perspectives, to raise some questions, and to explore systems, beliefs, and values informing and influencing actions. It is important to consider how people's belief systems influence, inform, and shape actions. This holds true in realms political, spiritual, and cultural. It also proves relevant in the ways in which we imagine, design, develop, and construct our buildings, cities, spaces, and places.

Appropriate solutions to some of our most daunting problems will arise through the concerted efforts, open dialogue, and collective wisdom of the wide array of stakeholders, professionals, politicians, decision makers, and citizens (both engaged and disenfranchised) who have the will and wherewithal to make a difference and to make the world safer, healthier, and better. It seems vital for us to critically examine, and question, our belief systems and their connections to the ways we define, refine, and realize progress. Architecture and Environmental Design, in both a philosophical and a practical sense, reflect as well as form greater aspirations, directions, and events of our times.