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111.
Future wired-wireless multimedia networks require diverse quality-of-service (QoS) support. To this end, it is essential to
rely on QoS metrics pertinent to wireless links. In this paper, we develop a cross-layer model for adaptive wireless links,
which enables derivation of the desired QoS metrics analytically from the typical wireless parameters across the hardware-radio
layer, the physical layer and the data link layer. We illustrate the advantages of our model: generality, simplicity, scalability
and backward compatibility. Finally, we outline its applications to power control, TCP, UDP and bandwidth scheduling in wireless
networks.
The work by Q. Liu and G. B. Giannakis are prepared through collaborative participation in the Communications and Networks
Consortium sponsored by the U.S. Army Research Laboratory under the Collaborative Technology Alliance Program, Cooperative
Agreement DAAD19-01-2-0011. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes
notwithstanding any copyright notation thereon. The work by S. Zhou is supported by UConn Research Foundation internal grant
445157.
Qingwen Liu (S’04) received the B.S. degree in electrical engineering and information science in 2001, from the University of Science
and Technology of China (USTC). He received the M.S. degree in electrical engineering in 2003, from the University of Minnesota
(UMN). He currently pursues his Ph.D. degree in the Department of Electrical and Computer Engineering at the University of
Minnesota (UMN).
His research interests lie in the areas of communications, signal processing, and networking, with emphasis on cross-layer
analysis and design, quality of service support for multimedia applications over wired-wireless networks, and resource allocation.
Shengli Zhou (M’03) received the B.S. degree in 1995 and the M.Sc. degree in 1998, from the University of Science and Technology of China
(USTC), both in electrical engineering and information science. He received his Ph.D. degree in electrical engineering from
the University of Minnesota, 2002, and joined the Department of Electrical and Computer Engineering at the University of Connecticut,
2003.
His research interests lie in the areas of communications and signal processing, including channel estimation and equalization,
multi-user and multi-carrier communications, space time coding, adaptive modulation, and cross-layer designs. He serves as
an associate editor for IEEE Transactions on Wireless Communications since Feb. 2005.
G. B. Giannakis (Fellow’97) received his Diploma in Electrical Engineering from the National Technical University of Athens, Greece, 1981.
From September 1982 to July 1986 he was with the University of Southern California (USC), where he received his MSc. in Electrical
Engineering, 1983, MSc. in Mathematics, 1986, and Ph.D. in Electrical Engineering, 1986. After lecturing for one year at USC,
he joined the University of Virginia in 1987, where he became a professor of Electrical Engineering in 1997. Since 1999 he
has been a professor with the Department of Electrical and Computer Engineering at the University of Minnesota, where he now
holds an ADC Chair in Wireless Telecommunications.
His general interests span the areas of communications and signal processing, estimation and detection theory, time-series
analysis, and system identification -- subjects on which he has published more than 200 journal papers, 350 conference papers
and two edited books. Current research focuses on transmitter and receiver diversity techniques for single- and multi-user
fading communication channels, complex-field and space-time coding, multicarrier, ultra-wide band wireless communication systems,
cross-layer designs and sensor networks.
G. B. Giannakis is the (co-) recipient of six paper awards from the IEEE Signal Processing (SP) and Communications Societies
(1992, 1998, 2000, 2001, 2003, 2004). He also received the SP Society’s Technical Achievement Award in 2000. He served as
Editor in Chief for the IEEE SP Letters, as Associate Editor for the IEEE Trans. on Signal Proc. and the IEEE SP Letters, as secretary of the SP Conference Board, as member of the SP Publications Board, as member and vice-chair of the Statistical
Signal and Array Processing Technical Committee, as chair of the SP for Communications Technical Committee and as a member
of the IEEE Fellows Election Committee. He has also served as a member of the IEEE-SP Society’s Board of Governors, the Editorial
Board for the Proceedings of the IEEE and the steering committee of the IEEE Trans. on Wireless Communications. 相似文献
112.
面向业务的网络性能管理系统是以网络中运行的业务为被管理对象的,而传统网络中间节点的封闭性限制了系统的实现。SONPMSA系统通信平台的设计与实现是通过引入主动代码技术、定义基于应用层实现的主动信包的格式、利用Java的平台无关性解决了主动代码分发机制中关键主动代码的解析和加载两大功能的设计与实现问题。从而解决了面向业务的网络性能管理系统通信平台动态地执行网络业务数据的管理问题。 相似文献
113.
114.
TANG Tian DENG Gang JIANG Jun School of Telecommunication Engineering Beijing University of Posts Telecommunications Beijing China 《中国邮电高校学报(英文版)》2007,14(2):94-98
Orthogonal frequency division multiplexing (OFDM) systems encounter performance degradations because of the time-varying (TV) channels common in wireless environments. The channel variations within one OFDM symbol introduce intercarrier interference. In this case, the frequency domain channel matrix is no longer diagonal, hence the corresponding channel estimation is challenging. In this article, two novel TV channel estimation approaches are proposed for the pilot-assisted OFDM systems, where the channel is approximated by the high-order linear model or the piece-wise linear model in time domain. The least square estimation is derived for the two kinds of channel approximations. The simulation is performed based on realistic TV channels with a fairly high Doppler spread. The results show the significant decreasing of the estimation mean square error using the proposed approaches. 相似文献
115.
116.
利用幅度特性对数字信号调制方式进行识别 总被引:1,自引:0,他引:1
数字调制方式的识别对于通信信号分析有着重要的作用。针对数字信号(2ASK,4ASK,2PSK,4PSK,2FSK和4FSK)的调制方式,本文提出了一种只利用调制信号瞬时幅度特性便可以对调制信号进行识别的新算法,利用特征参数提取与决策树分类器结合对以上6种数字信号进行调制识别。首先提出了使用希尔伯特变换和解析函数对数字信... 相似文献
117.
118.
武传坤 《电子科学学刊(英文版)》1993,(3)
There are many kinds of special relationships between multiple-valued logical func-tions and their variables, and they are difficult to be judged from their expressions. In thispaper, some sufficient and necessary conditions of the independence and statistical independenceof multiple-valued logical functions on their variables are given. Some conditions of algebraicindependence of multiple-valued logical functions on some of their variables and the way to de-generate a function to the greatest extent are proposed, and some applications of these resultsare indicated. All the results are studied by using Chrestenson spectral techniques. 相似文献
119.
120.