共查询到20条相似文献,搜索用时 46 毫秒
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超宽带无线通信标准的演进与展望 总被引:3,自引:0,他引:3
针对超宽带(Ultra-Wideband)标准中的多频带OFDM(MultibandOFDM)和直接序列CDMA提案进行了技术分析和比较,对UWB的标准化演进情况进行了论述。 相似文献
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本文介绍了超宽带技术的基本概念、目前主要的实现方案、国际上超宽带技术的规范化和标准化工作,以及超宽带技术的应用。 相似文献
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超宽带通信技术在隐蔽通信中的应用前景分析 总被引:2,自引:0,他引:2
从隐蔽通信的实际需要出发,在频域隐蔽通信原理的基础上介绍了超宽带信号的特性及参数,详细分析了超宽带信号的低截获特性,并与直接序列扩频通信作了比较,这对认识超宽带通信技术的应用价值有重要意义。 相似文献
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超宽带无线通信及其关键技术 总被引:17,自引:1,他引:17
从超宽带(UWB)的特点出发,分析了它的应用潜力、国内外发展现状以及关键技术;同时指出,许多课题有待于我们去进一步研究、解决,包括规则标准、信号选择、抗干扰问题、发送接收技术、集成电路开发等;最后展望了UWB的发展前景。 相似文献
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CharlesRazzell 《世界电子元器件》2003,(9):53-54,60
超宽带技术的发展与扩展频谱无线电技术的发展轨迹相类似,多年来一直被界定为军用技术,不过,如令已经广泛应用于普通消费类产品。根据最新的美国联邦通信委员会(FCC)的定义,中心频率大于2.5GHz的超宽带(UWB)系统需要拥有至少-10dB 500MHz带宽。 相似文献
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针对Lange耦合器在超宽带功率放大器中的应用,设计了一款基于实频技术的超宽带GaN功率放大器.匹配网络采用微带结构,应用微波CAD软件对所设计的电路进行仿真和优化,工作带宽为2~4 GHz,放大器增益大于26 dB,增益平坦度±0.3 dB,输出功率达到40 dBm,PAE大于25%.使用相对介电常数为3.38、厚度为0.508mm的介质基板实现该放大器,可广泛应用于通信领域. 相似文献
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In this paper, a ultra-wideband slot antenna is proposed and developed for multi-band wireless communication applications.
The radiating slot is fed by a microstrip line with a microstrip fork shaped tuning stub and backed by a finite metallic reflector.
The frequency characteristic and radiation performance of the proposed antenna are successfully optimized and the related
prototypes are fabricated and tested. The measured results show that the impedance bandwidth can cover the band from 1.85
to 6.1 GHz with return loss of better than 10 dB. The obtained patterns display a high gain and uni-directional radiation
patterns within interested bands. With these features, the proposed structure is suitable for application in wireless communication
systems, where a single antenna is needed to operate at multi-bands simultaneously, such as PCS (1.85–1.99 GHz), UMTS (1.92–2.17 GHz)
and all WLAN bands (2.4–2.48 GHz, and IEEE802.11a WLAN applications: 5.15–5.35 and 5.725–5.825 GHz). 相似文献
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In this paper a multi-user communication system based on ultra-wide band (UWB) technology is studied. UWB uses very short
pulses, so that the spectrum of the emitted signals may spread over several GHz. In order to implement multi-user communication,
the emitted signal must be modulated. One modulation scheme for UWB communications is to use analog waveforms to modulate
the data.
In this study, orthogonal waveforms called modified Gegenbauer functions are introduced as basis functions for the pulse shape
and compared to the previously proposed modified Hermite functions. It is shown that Gegenbauer functions offer better performance
for multi-user UWB communications.
Fouzia Elbahhar was born in 1975. She received the M.S. and Ph.D. degrees from the University of Valenciennes (France) in 2000 and 2004,
respectively. She is actually employed as Research Asistant at this university. She is especially involved in Ultra Wide Band
technology. Her primary interest is in systems dedicated to land transportation for communications, like vehicle to vehicle
telecommunication.
Atika Rivenq-Menhaj was born in 1970. She received her Diploma of Engineering and the M.S. degree in 1993 and then her Ph.D. degree in 1996,
from the University of Valenciennes (France). She actually is Assistant Professor in electronics at this university. Her primary
interest is in signal processing applied to intelligent transportation systems and telecommunication systems.
Jean-Michel Rouvaen was born in 1947. He received his M.S. degree in 1968 and his Ph.D. degree in 1971, from the University of Valenciennes (France).
He is now Professor of electronics at ENSIAME, an engineering school of university of Valenciennes. His primary interests
are in signal processing, nonlinear phenomena and telecommunications. 相似文献
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提出一种阻抗带宽比为12.9∶1的开槽结构的椭圆平面超宽带天线。该天线的辐射体采用扇形开槽的椭圆结构,而地板为矩形开槽结构,这两处适当位置合适尺寸的开槽使得天线得到了良好的阻抗匹配特性,进而实现了很好的超宽带特性。与以往所提出的超宽带天线相比,本天线尺寸更小,而带宽更宽,实现了在3.1~40GHz频带内反射损耗小于-10dB,在水平面的辐射方向图呈现良好的全向性。仿真和实验证明该天线具有良好的辐射特性及实用性,可以为现今及未来无线通信提供良好的选择。 相似文献
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GSM900/GSM1800双频网技术解决方案初步探讨 总被引:1,自引:0,他引:1
介绍了GSM1800的特点,并从网络设计方面对双频网的组网方式、覆盖方式、话务控制、切换算法等技术解决方案进行了初步探讨。 相似文献
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主要讨论了LMDS的技术特点、网络结构、以及相关组网设备,详细分析了LMDS系统的优缺点及发展现状和前景。 相似文献
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