Adaptive Coding and Modulation for Mobile Wireless Access Via High Altitude Platforms

In this paper we are concerned with broadband wireless access via high altitude platform system, providing the Internet access and broadband multimedia services to passengers equipped with WLAN terminals connecting through a collective terminal mounted on the train. The main challenge in such scenario is the development of efficient and reliable radio interface for the broadband communication link in the mobile wireless access segment. We are focusing on performance analysis of the adaptive coding and modulation scheme in the communication link between a high altitude platform and a collective terminal on-board moving train. In order to increase the reliability of the communication system in a fading environment we also exploit space and platform diversity. The proposed approach significantly increases the throughput of the wireless access system, while bit error rate remains below the target value regardless of the considered propagation environment.Tomaz Javornik received his B.Sc., M.Sc. and Ph.D. degrees in electrical engineering from the University of Ljubljana, Slovenia, in 1987, 1990 and 1993, respectively. He joined the Jozef Stefan Institute in 1987, where he currently works as a researcher in the Department of Digital Communications and Networks. He is involved in the study of digital radio-relay systems, modulation techniques, coding, adaptive signal processing and digital mobile communication systems.Mihael Mohorcic received B.Sc., M.Sc. and Ph.D. degrees in Electrical Engineering from the University of Ljubljana, Slovenia, in 1994, 1998 and 2002, respectively, and M.Phil. degree in Electrical Engineering from University of Bradford, UK, in 1998. He is a research fellow in the Department of Digital Communications and Networks at the Jozef Stefan Institute. In 1996/1997 he spent 12 months as a Visiting Scientist at University of Bradford, Bradford, UK. His research interests include development and performance evaluation of network protocols and architectures for mobile and wireless communication systems, and resource management in satellite and high altitude platforms networks with the emphasis on routing algorithms and traffic engineering. He is a member of IEEE.Ales Svigelj received his B.Sc., M.Sc. and Ph.D. degrees in Electrical Engineering from the University of Ljubljana, Ljubljana, Slovenia, in 1997, 2000 and 2003 respectively. He is a research associate in the Department of Digital Communications and Networks at the Jozef Stefan Institute. In 2000/2001 he spent one year as a visiting researcher at Leeds Metropolitan University in Leeds, UK. He has participated in several national and international projects. His research interests concern the development of telecommunications systems, network protocols and architectures for satellite, high altitude platforms and terrestrial mobile communication systems. In 2004 he was awarded with The Jozef Stefan Golden Emblem Prize for outstanding contributions made to science in Doctoral theses in the field of natural sciences in Slovenia.Igor Ozimek received his B.Sc., M.Sc. and Ph.D. degrees in electrical engineering from the University of Ljubljana, Slovenia in 1980, 1988 and 1993, respectively. Since 1980 he has been with the Jozef Stefan Institute, Ljubljana, where he works as a researcher. His current interests include digital communications,DSP processing and computer networks.Gorazd Kandus received B.Sc., M.Sc. and Ph.D. degrees in Electrical Engineering from the University of Ljubljana, Ljubljana, Slovenia, in 1971, 1974 and 1991, respectively. He is currently the head of the Department of Digital Communications and Networks at the Jozef Stefan Institute and a Professor at the Faculty of Electrical Engineering, Computer Science and Information Technology, University of Maribor. He spent one year at Worchester Polytechnic Institute, Worchester, MA, as a Fulbright Fellow and 5 months as a Visiting Scientist at the University of Karlsruhe, Germany. His main research interests include design and simulation of mobile and wireless communication systems and development of new telecommunication services. He is a member of IEEE and Upsilon Pi Epsilon.     

Performance of CDMA/PRMA as an Access Technique for Integrated Services in a UMTS High Altitude Platform System

High Altitude Platforms (HAPs) have gained a great interest in recent years. HAP systems will be global in nature but national in service provision. They will deliver IMT-2000 mobile and fixed wireless access using the proposed IMT-2000 terrestrial component radio transmission technologies and protocols. Under the above consideration, in this paper the performance of a MAC protocol based on the combination of the well-known Packet Reservation Multiple Access (PRMA) scheme with Code Division Multiple Access (CDMA) technologies in a Frequency Division Duplex (FDD) mode is studied, for a HAP operating at the 2 GHz frequency band at an altitude of 22 km. The impact of acknowledgement delay has been examined through computer simulations, along with the selection of suitable channel access functions (CAFs) to control the access of mobile users. Moreover the protocol performance is investigated in a cellular HAP environment and compared to that of a ground-based system. Finally, different traffic scenarios have been considered in order to investigate the access delay for non-real time traffic and the packet dropping performance for real time traffic.Nikolaos Batsios received his diploma degree in electrical & computer engineering (Telecommunication Division) from Aristotle University of Thessaloniki (Greece) in 2000. At the end of his studies, his diploma thesis was awarded from ERICSSON Hellas. He was also one of the six finalists of the IEEE Region 8 Student Paper Contest. He has worked as a Research Engineer in Space Engineering S.p.A. (Rome, Italy) and he was involved in ATB, ROBMOD and VIRTUOUS projects. Currently he is working in Intracom S.A. as Telecom Engineer. His research interests are in the field of satellite and terrestrial communication systems including physical layer design, medium access control layer architectures and protocols.Fotini-Niovi Pavlidou received the PhD degree in electrical engineering from the Aristotle University of Thessaloniki, Greece, in 1988 and the diploma in mechanical-electrical engineering in 1979 from the same institution. She is currently an associate professor at the Department of Electrical and Computer Engineering at the Aristotle University engaged in teaching for the under- and post-graduate program in the areas of mobile communications and telecommunications networks. Her research interests are in the field of mobile and personal communications, satellite and HAP communications, multiple access systems, routing and traffic flow in networks and QoS studies for multimedia applications over the Internet. She is involved in many national and international projects in these areas and she has chaired the European COST262 Action on Spread Spectrum Techniques. She has served as a member of the TPC of many IEEE/IEE conferences. She is a permanent reviewer for many international journals. She has published about 80 papers in refereed journals and conferences. She is a senior member of IEEE, currently chairing the joint IEEE VTS & AESS Chapter in Greece.     

Satellite Navigation and Communications: An Integrated Vision

The paper addresses advanced layered architectures for the development of integration scenarios between satellite navigation and communications systems and services. This synercic cooperation represents – in author's vision – the core of future global networks. The concept of integration and its translation into an integrated network is displayed, together with examples of possible architectures for navigation-communications applications. In this frame, the paper addresses also the possible exploitation of stratospheric platforms (HAP) as permanent and on-demand blocks concurring to the effective deployment of the integrated vision. 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 (RTV) (1986–1991); Associate Professor in Telecommunications at Univ. of L'Aquila (1991–1994) and at the University of RTV (1994–2000). Since November 2000 she is Full Professor in Telecommunications at the RTV (Faculty of Engineering), teaching DSP, Information and Coding. Since 2003 she directs a Master in “Advanced Satellite Communications and Navigation Systems” at RTV.Since 1999 she has been appointed member of the Board of Governors of the IEEE AES Society.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 and on satellite-HAP integrated networks for multimedia applications (SHINES), co-financed by MIUR. She co-ordinates RTV 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 NEXWAY; GALILEO JU 1st Call: VERT (VEhicular Remote Tolling); and in the ASI program on V-band payloads (TRANSPONDERS).She is Editor of the IEEE Transactions on AES for “Space Systems”, Chair of the IEEE AES Space Systems Panel. Since 2002, she is co-chair of Track 2 “Space Missions, Systems, and Architecture” of the AES Conference; she has been re-appointed in the IEEE Judith A. Resnik Award Committee for 2004; she has been member of TPC for PLANS 2004.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 220 papers, on international journals/transactions and proceedings of international conferences, book chapters and books.She is an IEEE Senior Member (S'84-M'85-SM'94).     

Interference Environment Between High Altitude Platform Networks (HAPN), Geostationary (GEO) Satellite and Wireless Terrestrial Systems

A new broadband telecommunication system has been recently proposed for provision of fixed, mobile and personal services adopting the use of high altitude platform stations placed in a fixed position in the stratospheric layer at heights from 15.5 to 30 km. The International Telecommunication Union (ITU) has allocated a pair of 300 MHz of spectrum in the V band for these services, which is already in use by geostationary satellite and wireless terrestrial systems as co-primary allocations. This paper addresses an in-depth co-channel interference analysis and proposes a C/I (carrier-to-interference) calculation model applicable to all the interference propagation paths as well as sharing criteria between HAPN, GEO satellite and wireless terrestrial systems extracted from simulations performed in urban, suburban and rural environments. By evaluating the interference density cumulative probability distribution functions, sufficient geographical separation distances between the ground stations are proposed which guarantee the harmonic co-existence between the three broadband systems. Maintaining the platform stable in the stratosphere is a key issue, and in this paper the effect of the three different stratospheric platform’s movement models (ITU, HELINET, HALO) appearing in the literature, on C/I levels is estimated.Vasilis F. Milas {received the Diploma in Electrical and Computer Engineering from the National Technical University of Athens, Greece, in 2000. From October 2000 until October 2001 he joined Space Engineering S.P.A in Italy (Rome) as a field practicing engineer where he was mainly involved into the design and realization of satellite telecommunication systems. Since November 2001 he is a member of the Mobile Radiocommunications Laboratory at the National Technical University of Athens working towards his Ph.D. degree with focus on high altitude platform systems and interference characterization on wireless communication systems.Philip Constantinou {received the Diploma in Physics from the National University of Athens in 1972, the Master of Applied Science in Electrical Engineering from the University of Ottawa, Ontario, Canada in 1976 and the Ph.D. degree in Electrical Engineering in 1983 from Carleton University, Ottawa, Ontario, Canada. From 1976 to 1979 was with Telesat Canada. In 1980 he joined the Ministry of Communications in Ottawa, Canada. From 1984 to 1989 he was with the National Research Centre Demokritos in Athens, Greece were he was involved on several research projects in the area of Mobile Communications. In 1989 he joined NTUA where he is currently Professor. His current research interests include Mobile Satellite Communications and Interference Problems on Digital Communications Systems.     

卫星导航接收机抗干扰性能评估方法研究

卫星导航接收机的抗干扰是导航战研究的一项重要内容。合理的抗干扰性能评估方法是对接收机的抗干扰性能进行正确评估的基础,目前卫星导航接收机还没有建立统一的抗干扰性能评价方法。在吸取GPS系统抗干扰性能评估方法的合理性的基础上,提出一种在接收机输入端对抗干扰性能进行评估的方法,与传统的抗干扰性能评估方法相比,该方法更具有工程实际意义。     

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.     

固定无线接入系统对卫星地球站的干扰分析

为了使共用同一频段的3.5 GHz固定无线接入系统（FWA）和C波段固定卫星业务（FSS）实现共存,就需要对这两个系统间的干扰进行分析。采用确定性计算方法主要研究了在建筑物密集但排列比较整齐的地形中3.5 GHz固定无线接入系统对C波段卫星地球站产生的同频干扰,给出了同频干扰的计算方法,并进行了仿真分析,从而验证了在这种地形下实现两系统干扰共存的可行性。     

无线移动网络的综合服务模型与资源预留研究

本文讨论了无线移动网络的综合服务模型,提出应按照服务承诺是否移动相关以及资源是否独占来对实时服务进行分类,并定义了组成该综合服务模型的五种服务承诺.本文同时还讨论了移动无关与移动相关服务的资源预留解决方案,提出在移动无关服务中用移动代理技术建立端-端的主动预留与被动预留,而在移动相关服务中只建立主动的端-端预留并在相关的无线链路上被动预留资源.     

Effect of Antenna Beam Pattern and Layout on Cellular Performance in High Altitude Platform Communications

High Altitude Platforms may offer high spectrum efficiency by deploying multi-beam, multi-cell communications networks. The properties of the antennas carried by the HAP payload are key to the effective exploitation of these benefits. This paper compares different models for the antenna sidelobe region and quantifies, in each case, the carrier to interference ratio for a 3 channel re-use plan. Networks of 121 and 313 cells are compared. We show how the ITU recommended pattern for the 47/48 GHz band leads to pessimistic results compared to an adapted pattern which fits that of measured data for an elliptic beam lens antenna. The method is then extended to consider other radiation patterns. Spectrum sharing issues are explored with reference to further ITU recommendations and comparison with measurement data. Finally, an ITU type cellular layout which uses the same antenna for each cell is compared to an alternative hexagonal layout where each cell has equal size. John Thornton is a physics graduate of the University of York, UK, obtained an MSc. in microwave physics from the University of Portsmouth, UK, in 1995 and a PhD from the UK's Open University in 2002. He has held research posts at the Rutherford Appleton Laboratory, UK, developing sub-millimetre wave solid state sources and receivers, and at the University of Oxford, on projects including passive radar transponders, array antennas and superconducting filters. In 2000 he returned to York to join the Department of Electronics as a Research Fellow, where his research interests include microwave techniques, wireless broadband and scanning antennas. David Pearce BA(Cantab), DPhil(York) MIEEE, AMIEE, is a lecturer in the Department of Electronics in the University of York and has worked in the field of Fixed Wireless Access schemes for the last five years. Prior to this he worked developing new copper-based local area network schemes in both academia and industry; including heavy involvement in the standardisation work for ISO-8802.5 token ring. Current research interests are focused on media access schemes for multimedia traffic and adaptive techniques for optimising the bandwidth efficiency of wireless networks. David Grace received his MEng in Electronic Systems Engineering and D.Phil from the University of York, UK in 1993 and 1999 respectively. Since 1994 he has been a member of the Communications Research Group where he is now a Senior Research Fellow whose current interests include radio resource management for broadband communications, particularly from high-altitude platform, and terrestrial ad hoc networks. He is Principal Scientific Officer for CAPANINA, a major European Framework 6 project developing broadband communications from high-altitude platforms. He has been an invited speaker at several conferences and industrial locations in the fields of HAP systems. He is a nominated Researcher in the European NEWCOM Network of Excellence, and a Director of SkyLARC Technologies Ltd, a York based company, specialising in broadband communications from aerial platforms. He is a member of IEE and IEEE. Masayuki Oodo received B.E., M.E., and D.E. degrees in Electrical and Electronic Engineering from Tokyo Institute of Technology, Japan, respectively in 1992,1994, and 1997. In 1997, he joined the Communications Research Laboratory (CRL), now part of the National Institute of Information and Communication Technology (NICT). Since July 2004 he has been a visiting research fellow at the University of York. His research interests are array antennas for wireless communications and frequency-sharing between HAPS and other systems. Dr. Oodo received the Paper Presentation Award from IEEJ (The Institute of Electrical Engineers of Japan) in 1995, the Young Scientist Award from URSI in 1996, the Young Engineer Award from IEICE (The Institute of Electronics, Information and Communication Engineers) of Japan in 1997, and the Young Engineer Award from IEEE AP-S Tokyo Chapter in 1998. Konstantinos Katzis received his BEng degree in Computer Systems Engineering in 2000 and his MSc in Radio Systems Engineering in 2001, both from the University of Hull, UK. Since 2001 he has been a member of the Communications Research Group at York where he has been working on Resource Allocation Techniques for HAPs for his PhD degree. Currently he is a Research Associate working on Radio Resource Management for the European project CAPANINA. His current research interests include Resource allocation and spectrum management, multiple access schemes and medium access control protocol modelling. Tim Tozer MA(Cantab), CEng, FIEE, MIEEE, is Senior Lecturer in Electronics at York, since 1987, and leader of the Communications Research Group. Research interests include: wireless access techniques; multi-user, satellite and High Altitude Platform communications. He has held numerous grants and research contracts from industry, government and international organisations, and is a named author on over 180 technical publications. He is active in the IEE Professional Network on Satellite Systems and Applications. Tim is a regular invited presenter at international conferences, workshops and tutorials, in the fields of VSAT and HAPs communications. He has previous experience in industry, including work on military satellite systems at DERA (now QinetiQ). Tim is also Managing Director of SkyLARC Technologies Ltd.     

基于STK的预警卫星部署与性能分析

预警卫星对导弹的早期预警是反导防御系统有效作战的关键环节,而红外预警卫星就是实现弹道导弹早期预警的有效手段。利用卫星工具包（STK）仿真工具,研究红外预警卫星部署的方法,并通过STK仿真出来的数据分析其探测能力。该方法可得到针对特定热点地域反导预警卫星的合理部署方案。     

星基增强系统接收机中的导航比特同步设计与性能仿真

星基增强系统(SBAS)中导航电文速率为500符号/秒,针对其弱信号时找导航比特边界难的特点,提出了基于最大似然算法的比特同步算法,给出了在SBAS接收机中比特同步的应用公式和实现方法,并进一步创新性地设计了包含有软判决和多次判决的比特同步综合流程;最后在多种导航比特分布的情形下,对最大似然比特同步算法进行了不同载噪比下的性能仿真,确认了此算法在接收信号很弱时仍然有效。     

FCC卫星通信业务及台站概述

文章从美国联邦通信委员会对美国非联邦使用的卫星通信业务和台站的定义出发,分析其业务定义和使用台站分类的方法,总结出美国非联邦卫星通信业务及其使用台站的管理特点,为我国空间业务的全球布局提供参考数据。     

High Altitude Platform Station (HAPS): A Review of New Infrastructure Development for Future Wireless Communications

This paper looks into the relatively new field of high altitude platform stations. HAPS is seen as a ‘middle ground’ between the terrestrial and satellite cases, and aims to exploit of the advantages of both types of system. Since HAPS is such a new field, this paper focuses on the technology behind a HAPS communications system, how this has developed, and compares it to the terrestrial and satellite equivalents. One important area that is being investigated is the applications for which HAPS should be used. This is a critical issue if a significant business case is to be made for HAPS. Worldwide HAPS projects and research issues are also highlighted. Finally, the review concludes with the remarks on the future of HAPS for wireless communications systems.     

基于DVB-RCS和WiMAX的卫星宽带无线接入体系设计

卫星宽带通信已成为目前研究的热点.现有的DVB-RCS卫星无线接入标准以物理层规范为主,尚未构成完整的卫星宽带无线接人体系.本文基于DVB-RCS技术,针对卫星宽带无线接入的需求和特点,结合地面WiMAX宽带无线接入技术,给出了卫星宽带无线接人体系的功能架构设计,并具体分析了各主要功能的设计与实现方法.     

基于智能手机终端的数据业务质量监测系统的研究与实现

本文首先简要分析了移动数据业务的技术特点、发展趋势以及维护工作中存在的困难。然后,通过技术经济分析,提出了基于智能手机终端平台的质量监测系统的技术解决方案。最后,展望了应用前景。     

基于ADS的卫星链路对抗仿真与效果评估

ADS软件广泛应用于数字基带、射频和通信系统仿真,具有高效、便捷和协同仿真能力强的特点。介绍了典型的卫星通信系统和通信过程,并将ADS软件应用于复杂电磁环境模拟、卫星通信系统和地面对抗终端构建以及干扰效果评估。通过对仿真工具、测试工具和数据统计分析工具的使用,得出干扰信号调制样式、干信比和干扰信号码速率等因素对干扰效果的影响,并提出了部分优化干扰系统,提升干扰效果的建议。     

基于无线网络性能数据的用户业务行为分类与感知评估技术

提供了一种基于无线网络性能数据的用户业务分类方法,同时提供完备的感知分析技术.通过研究各类应用的具体资源占用特征,研究人员设计出有效的业务类型区分方法;同时考察不同应用对各种KPI的敏感程度以制订准确的感知评估规则.经过大量测试验证,该方法具有分类评估准确,效率高,处理开销小等优点.     

Voice/Data Integrated Wireless Channel Access in Third Generation Digital Cellular Networks: The Performance of Bursty Data Generated by Interactive Applications

Mobile wireless communications, which includecellular telephones, land mobile radio, and personalcommunications systems, have experienced enormous growthover the last decade. Data services represent a critical component of future wirelesscommunications, but have received little attention sofar. While some attention has been given to specializedmobile data networks, less has been directed at the ongoing design of data services in evolvingthird generation digital cellular wireless networks. Inthis work we present the results of a simulation studythat explores the performance of a Reservation Random Access (RRA) scheme for transmittingdata packets over a common radio broadcast channel in acellular radio environment. In addition to voicetraffic, we consider data packet traffic generated by interactive applications. It is expected thatsuch applications will be very important in thirdgeneration wireless access mobile communication systems.Through an extensive simulation study of the data message delay distribution, we show that theproposed RRA scheme, originally designed under thePoisson data message arrival process assumption, canalso efficiently operate and be optimized under theextremely bursty data message arrival processcharacterized by independent, identically distributed,Pareto message interarrival times.     

PTN技术概览及作为综合业务传送网应用价值的探讨

简要介绍了PTN技术的技术特征和最新标准化进展,分析了其作为综合业务传送网的技术优势,并结合国内实际应用案例总结了网络演进策略。     

基于CTMC和状态空间模型的宽带无线接入网的QoS性能研究

为了实现同一地域范围内的众多用户在有限带宽条件下提出的高QoS要求,本文对基于IEEE 802.16标准的宽带无线接入网中数据包级QoS（Quality of Service）性能进行了研究.具体做法是,首先采用批马尔可夫到达过程（BMAP,Batch Markov Arrival Process）和连续时间马尔科夫链（CTMC,Continuous Time Markov Chain）对到达过程和流量源进行建模,得到更符合实际和更准确的排队模型;然后基于状态空间,对一个无线接入网络系统进行建模,通过对得到的系统模型并结合前面得到的排队模型的深入分析,从而获得该模型下的各项QoS性能指标,如平均队列长度、丢包率、队列吞吐量和平均包时延.仿真实验结果表明,本文提出的算法模型相比于其他典型的算法模型,能够使得各项QoS性能指标有较大的改善和提高.