Convergence Towards 4G: A Novel View of Integration

Integration and convergence of different access technology is a key concept of 4G systems. This integration also includes the interface among terrestrial and aero-space components, whose importance has been so far under-estimated and not deeply understood. In this paper, a layered model of the 4G integrated network vision is introduced, highlighting details about the aero-space component. The concept of integration is discussed under different viewpoints, particularly highlighing integration among aero-space segments and related services (i.e. navigation). Examples of integration scenarios identified and investigated in the frame of research programs co-funded by Italian institutions are also displayed in the paper.Ernestina Cianca graduated cum laude in Electronics Engineering in 1997 at the University of L’Aquila. She was Italtel/Siemens (L’Aquila) from 1997 to 1998. She got her Ph.D. degree from the University of Rome Tor Vergata (URTV). The thesis work was on power management in CDMA-based satellite systems. She has been employed by the University of Aalborg, Denmark, in the Wireless Networking Groups (WING), as Research engineer (2000–2001) and as Assistant Professor (2001–2003). In particular, from Sept. 2002 she has been Technical Manager of Aalborg University for the IST-STRIKE project. She is currently Assistant Professor in Telecommunications at the URTV (Dpt. of Electronics Engineering), teaching DSP, Information and Coding. Her research mainly concerns wireless access technologies (CDMA and MIMO-OFDM-based systems), in particular, Radio Resource Management at PHY/MAC layer, ARQ/HARQ, TCP-IP issues over wireless links, integration of terrestrial and satellite systems. She has been the vice-coordinator of the following national research programs: CABIS, on CDMA integrated mobile systems (2000–2002) and SHINES, on satellite-HAP integrated networks for multimedia applications co-financed by MIUR (2002–2004). She currently working on various European Projects. She is author of about 40 papers, on international journals/transactions and proceedings of international conferences.Mauro De Sanctis received the “Laurea” degree in Telecommunications Engineering from the University of Roma “Tor Vergata” in 2002. He is currently a Ph.D. Student and Assistant Professor in the Department of Electronics Engineering of the same University. He is involved in the DAVID (DAta and Video Interactive Distribution) satellite mission of the ASI (Italian Space Agency); his research is funded by the ASI. He is also involved in the MAGNET (My personal Adaptive Global NET) European FP6 integrated project and in the SatNEx European network of excellence. He worked on Italian national research projects on satellite-terrestrial systems integration such as SHINES (Satellite and HAP Integrated Networks and Services) and CABIS (CDMA for Broadband mobile terrestrial-satellite Integrated Systems). On autumn 2004 he joined the CTIF (Center for TeleInFrastructure), a research center focusing on modern telecommunications technologies located at the University of Aalborg (Denmark). His main areas of interest are: integration of different satellite networks, stratospheric platforms and terrestrial networks in a multi-layered fashion, internetworking and resource management in satellite systems and energy efficiency of WPAN systems.Marina Ruggieri graduated in Electronics Engineering in 1984 at the University of Roma. She was: with FACE-ITT and GTC-ITT (Roanoke, VA) in the High Frequency Division (1985–1986); Research and Teaching Assistant at the University of Roma Tor Vergata (URTV) (1986–1991); Associate Professor in Telecommunications at the University of L’Aquila (1991–1994). Since November 2000 she is Full Professor in Telecommunications at the URTV (Dpt. of Electronics Engineering), teaching DSP, Information and Coding. Since 1999 she is member of the Board of Governors of the IEEE AES Society. Since 2004 she is member of the Technical-Scientific Committee of the Italian Space Agency (ASI). Her research mainly concerns space communications and navigation systems (in particular satellites) as well as mobile and multimedia networks. She is the Principal Investigator of: satellite scientific communications missions (DAVID, WAVE) of ASI; national research programs (CABIS) on CDMA integrated mobile systems (2000–2002) and on satellite-HAP integrated networks for multimedia applications (SHINES), co-financed by MIUR (2002–2004). She co-ordinates the URTV Unit in various European Projects: EU FP6 IP MAGNET (My personal Adaptive Global NET); EU ASIA LINK EAGER-NetWIC (Euro-Asian Network for Strengthening Graduate Education and Research in Wireless Communications); EU Network of excellence NEXWAY; GALILEO JU 1st Call – July 2003: VERT (VEhicular Remote Tolling); and in the ASI program on V-band payloads (TRANSPONDERS). She is Editor for Space Systems of the IEEE Transactions on AES. She was awarded the 1990 Piero Fanti International Prize and she had a nomination for the Harry M. Mimmo Award in 1996 and the Cristoforo Colombo Award in 2002. She is author of about 180 papers, on international journals/transactions and proceedings of international conferences, book chapters and books.     

Scalable, Hybrid Optical-RF Wireless Communication System for Broadband and Multimedia Service to Fixed and Mobile Users

This paper describes a system concept for providing, flexible high capacity multimedia communication that compliments terrestrial cellular communication systems, by supporting end-to-end broadband information services. A key element of the proposed concept is the use of optical HAP-HAP and HAP-satellite links using single color (SONET protocol based) or upon multicolor DWDM technology. The effectiveness of optical communication links is enhanced through the use of advanced optical fine pointing and tracking technology. A concept for a hybrid, optical-RF, HAP based wireless communication is presented and key technologies, capabilities and limitations are described. This revised version was published online in July 2006 with corrections to the Cover Date.     

LMSS中的遮蔽衰落模式分析

本文对ＬＭＳＳ遮蔽环境中的衰落分布进行了分析，利用现有实验数据和ＥＲＳ模式的基本形式，重新确定了经验模式参数在不同遮蔽条件下与仰角和频率的关系；     

LMSS中的多径衰落预测模式

本文讨论了陆地移动卫星业务（ＬＭＳＳ）中的多径衰落分布，综合国外有关实验数据导出了适用于地面多径接收环境中的经验衰落预测模式。比较结果表明，该模式有较好的精度，而Ｎａｋａｇａｍｉ—Ｒｉｃｅ分布偏离实验结果较大。     

Impact of Galileo commercial service on location-based service providers: business model analysis and policy implications

Today's mobile location-based services (LBSs) largely depend on a free-of-charge, best-effort positioning technology, called global positioning system, which is controlled by the US military. The European alternative Galileo will not only offer a similar best-effort system by 2020, but also a premium-rate service known as Galileo commercial service (CS). Galileo CS is planned to provide higher positioning accuracy, improved security due to signal authentication and service guarantee. While the technology behind Galileo is often studied, the impact of Galileo CS on the LBS marketplace is rarely discussed. In this article, we fill this gap by analysing how improved accuracy, authentication and service guarantee may impact the business models of LBS providers. We do so by interviewing service providers, policy makers and industry experts on what new services would be enabled; technological alternatives that may emerge in the coming years; and organisational and financial issues that service providers face when adopting such a premium-priced positioning signal. We find that a more accurate, secure and reliable global navigation satellite system signal enables a range of new LBSs, although several alternative technologies are emerging that may make Galileo CS obsolete before it is even launched. To convince the LBS providers to adopt Galileo CS, the institution operating Galileo should get governments on board early on for building trust and should consider progressive pricing schemes. Still, service providers are sceptical about adopting Galileo CS, and the hope to recoup any investments in Galileo may thus be in vain.     

一种面向主动交通安全的城市车辆在线位置服务系统

针对车辆对交通安全的迫切需求,提出一种基于北斗、GPS和GLONASS卫星导航应用平台,集成城市车辆主动交通安全模型、高可靠无缝融合传输网络、城市车辆多维综合信息高速采集系统、面向主动交通安全的一体化实时时空数据处理车载智能终端、网络管理及服务一体化平台软件设计等方面的技术,构建一种面向主动交通安全的城市车辆在线位置服务系统,减少城市交通事故,缓解城市交通拥堵,为相关项目的实施提供设计思路和技术路线.     

Integrated global networks,tomorrow' communications today

This article presents an overview of the concept of a multiple purpose global satellite network. It identifies some of the main needs of telecommunication services today, and projects the potential of future demands. It also describes the great possibilities of economic expansion and mass participation in the growth and prosperity of a nation, if basic telecommunication services are accessible on a global scale. The study suggests that the rapid recovery of capital investments on universal satellite networks lies in developing regions through cost-effective service diversification.     

Identification of preconditions for an emerging mobile LBS market

Location information has become a very important horizontal service component for a wide range of vertical mobile applications. This enabled multiple innovative mobile location-based services (LBS) that range from conventional mapping and navigation services featuring millions of points of interest (POI) to location-aware content delivery and mobile social networking. Providing a whole new world of opportunities for device and application vendors, network operators, content providers and prospective consumers, mobile LBS have potential to become one of the core businesses in today's mobile arena. However, the future of this market is not fully transparent due to several uncertainties associated with a mixture of technologies, service demand, consumer attitude, privacy aspects of using LBS and a complex value network. In this study, we identify and analyse a set of preconditions for an emerging mobile LBS market in its present evolution phase. The history of LBS motivates us to take a closer look at this emerging market and try to understand what the main reasons for LBS initial failure have been and what is still missing in this market today to emerge successfully. To focus on the most relevant issues, we construct our own research framework containing three main dimensions: technological advance and standardisation, value network and value proposition. Within these dimensions, we compare the early state of mobile LBS with the present situation and analyse the key factors presently crucial for LBS proliferation.     

Integration of Terrestrial and Satellite Networks: Technology,Services and Applications

In support of the growing demand for multimedia information services andseamless nomadic roaming, networks of the future must be increasingly flexible and resource efficient. However, current networking protocols must be enhanced for use in satellite, as wellas, wireless networks. In this paper, issues and trends with respect to the integration of future satellite and terrestrial networks will be examined.     

高空平台不稳定对平台间光通信性能的影响及抑制

考虑晃动对平台间光通信的影响,结合Γ大气扰动模型,推导出平台间光通信的误码率表达式,进一步分析平台晃动条件下平台间光通信捕获、跟踪和瞄准(APT)系统的设计要求。结果表明,发送端偏转和接收端的垂直运动对平台间光通信性能影响较大,而接收端偏转和发送端的水平运动对平台间光通信性能影响较小;满足平台间光通信误码率小于10-6的APT系统瞄准精度应低于50μrad。     

Robust guaranteed cost control for a class of two-dimensional discrete systems with shift-delays

This paper considers the problem of robust guaranteed cost control for uncertain two-dimensional (2-D) discrete shift-delayed systems in Fornasini–Marchesini (FM) second model. The parameter uncertainty is assumed to be norm-bounded. The problem addressed is the design of state feedback controllers such that the closed-loop system is asymptotically stable and an adequate level of performance can be guaranteed for all admissible uncertainties. The cost function with shift-delays is proposed and an upper bound of the cost function is given. In terms of a linear matrix inequality (LMI), a sufficient condition for the solvability of the problem is obtained. A desired state feedback controller can be constructed by solving a certain LMI. A numerical example is provided to demonstrate the application of the proposed method.     

低轨卫星星座网的切换研究

提出了一种适用于装备有星际链路的低轨卫星星座网的切换策略——最小跳数切换策略。该策略以端到端连接的跳数为基础,充分利用了低轨星座网的特点,将切换过程与路由有机地结合为一体,有效解决了不同卫星之间的切换问题。仿真结果表明,同已有的切换策略相比,该策略能够提供一定程度的QoS保障,获得较好的系统性能,如较低的传播延时和较小的切换频率,具有很好的实用价值。     

一种新型中轨卫星移动通信系统设计简介

本文提出了一种新型的中轨卫星移动通信系统设计方案,该系统的特点是采用特殊中的轨赤道轨道卫星星座,所需卫星数目少,成本低,采用波束相对地面静止的凝视天线,避免了由于卫星和地面终端移动造成的通信中断和由此而需的波束切换技术,可靠性强,采用国内技术能技术的通用小卫星平台,制造成本低,投资风险小,文中给出了系统结构,特性参量及工作原理的简单描述,讨论了所需的关键技术和存在的问题。     

卫星技术在地震行业中的综合应用

针对地震行业用户对卫星技术的需求,结合卫星遥感、卫星通信及卫星导航技术的特点及优势,介绍了一种应用于地震行业的卫星综合应用系统方案,探讨了如何建立地震行业防震减灾的卫星综合应用服务平台,提高防震减灾水平。     

宽带卫星多媒体标准化

欧洲电信标准学会（ETSI）正在研发未来宽带卫星系统的标准,本提供对ETSI研究工作的总看法,同时还提供其它标准组织,例如DVB计划,ITC和TETF的研究情况,探讨潜在的应有领域。     

从能用到好用 卫星通信技术发展趋势分析

本文从卫星通信技术和应用发展历史提出从“能用”到“好用”的技术发展方向,并从业务、网络、标准、终端等方面对卫星通信的近期发展趋势进行整理和分析,提出发展关键在于保持全球覆盖优势的同时,降低应用成本、提升网络能力,并与地面通信手段相融合,拓宽卫星互联网应用市场。