A novel design using meshed-planar fan-electromagnetic bandgap (MP-FEBG) structure for ultra-wideband (UWB) antenna

A concept to combine the plane fan antenna with the meshed-planar electromagnetic bandgap (MP-EBG) structure is proposed; and then, based on the theory, a novel ultra-wideband (UWB) antenna with double-deck meshed-planar fan-electromagnetic bandgap (MP-FEBG) is designed. The structure of the sector is beneficial to the increase of the antenna bandwidth. The double layer structure can greatly reduce the size of the antenna, and the aperture structure can easily adjust antenna's performance. The antenna is compact in size, suitable for UWB applications. An antenna model was established on the substrate of FR4 and at least 79.1% dimension of the antenna was reduced by the traditional UWB antenna in the related documents. The simulation results show that the antenna can achieve a wide bandwidth from 3.20 to 15.78 GHz with return loss less than −10 dB and exhibit stable antenna gain. Furthermore, the measurement result is in better consistence with the simulation result.     

A Novel UWB Antenna with Small Side-Leakage

A successful design for a UWB (ultra-wideband antennas) antenna based on NRD-guide (nonradiative dielectric waveguide) with small side-leakage is presented. The rule of the theoretical selection of its parameters, if NRD-guide is used as the UWB antennas, is studied firstly, then the temporal propagation characteristics of the NRD-guide and the radiation characteristics for an tapered open-ended NRD-guide are calculated by FDTD (finite-difference time-domain) method.     

MBOK调制方式在基于并扩的超宽带系统中的应用

并行组合扩频通信技术( PCSS)和超宽带(UWB)通信技术因为具有高效通信能力和保密通信性能而成为该领域的研究热点.该文在分析并行组合扩频通信和超宽带通信系统技术特征的基础之上,结合这2种通信方式的技术优势,提出了一种基于并行组合扩频的超宽带通信系统方案,并将高性能的多元双正交键控(MBOK)调制方式应用到该系统.仿真结果表明,在相同条件下,当误码率为10-4时,MBOK调制方式较传统的脉冲位置调制(PPM)方式的信噪比有约9 dB的提高.     

6.2～9.4GHz DC-OFDM超宽带接收机射频前端设计

设计了一个用于6.2~9.4 GHz超宽带中国国家标准的接收机射频前端.通过采用共栅输入、电容交叉耦合的低噪声放大器和正交跨导级合并的折叠型混频器,实现了对UWB小信号的放大和下变频.设计方案采用TSMC 0.13μm 1P8M RF CMOS工艺流片验证并进行测试.测试结果表明,输入匹配在6.2~9.4 GHz频段内...     

一种基于正交脉冲调制的IR-UWB同步算法

超宽带信号的快速同步捕获是UWB系统实现的一个重大挑战.提出了一种基于修正Hermite多项式脉冲的同步捕获方法,脉冲信号选用零阶和一阶修正Hermite多项式,2种脉冲信号按特殊顺序作为超宽带脉冲信号,同时与滑动相关结合.该算法不需要在本地生成模板,只需进行接收信号与其自身延迟之间的相关运算.其中低阶的修正Hermite多项式的正交性使算法得到更精确的同步参数.理论分析及仿真实验结果表明,该算法实现了预期的性能优化.     

基于UWB技术的高速无线个域网MAC协议研究

介绍了基于UWB技术的高速无线个域网和IEEE802.15系列标准.讨论了高速无线个域网MAC协议的研究现状,并结合UWB技术提出了IEEE 803.15.3 MAC协议的可能改进方法,分析了目前改进方案的研究热点.     

A High-Power Reflector Impulse Antenna with Dual-Tem Source

There are different demands on radiation efficiency and direction pattern according to various ultra-wideband (UWB) antennas and high power applications. To obtain more radiating gain on bore-sight of paraboloidal reflector and centralized radiating direction, a novel feeding structure called dual-TEM source has been designed and applied in half-paraboloidal reflector impulse radiating antenna (IRA) applications. Simulation results proved that this proposed half-paraboloidal reflector IRA with dual-TEM source provided greater radiation performance on bore-sight as a result of the synthesized power in the aperture space of paraboloid. Moreover, lots of simulation work and comparison have been done in different feeding models to summarize a relative optimal feeding structure.     

包络分析在超宽带信号采集中的应用

室内环境下超宽带信号具有丰富的多径分量,在时域中这些分量表现出簇（cluster）的形式,簇在时域上类似于幅度调制,可采用包络分析法对其进行分析.介绍了利用小波变换进行超宽带信号包络分析的方法,给出了接收信号包络的时域表达式,并对低信噪比下超宽带信号进行了包络提取,结果显示该方法实现了簇内多径分量的合并,并具有很强的去噪作用.包络分析方法对于那些难以建立模型的传输环境以及能够建立模型但难以提取参数的场合下超宽带信号的采集具有重要的意义,它指出了传统的包络分析技术可用于超宽带信号的采集.     

Bayesian fusion of GNSS,ITS-G5 and IR–UWB data for robust cooperative vehicular localization

In the automotive domain, Cooperative Localization (CLoc) is a new promising paradigm that aims at outperforming conventional Global Navigation Satellite Systems (GNSS) in terms of positioning accuracy, robustness, and service continuity, by relying on Vehicle-to-Vehicle (V2V) communications and hybrid data fusion. However, the growing number and the variety of the sensors aboard vehicles raise unprecedented challenges, especially in the context of distributed fusion approaches. This paper thus compares parametric and nonparametric Bayesian data fusion engines (e.g., based on cooperative variants of the Extended Kalman Filter (EKF) and Particle Filter (PF), respectively), while validating a CLoc scheme suitable to Vehicular Ad Hoc Networks (VANETs). More particularly, absolute position information from both onboard GNSS receiver and ITS-G5 V2V messages, as well as relative distance measurements based on the Impulse Radio–Ultra-Wideband (IR–UWB) technology, are combined into a single location solution that is hopefully more robust and more accurate than that of standalone GNSS. First, we investigate V2V ranging accuracy on a highway under real mobility conditions. In the same environment, we then provide offline validations of CLoc positioning, confirming significant performance gains through cooperation over conventional GNSS, even in case of poor initialization. In this specific context, the PF solution is thus shown to yield even better accuracy in comparison with EKF, thanks to its fine robustness against faced non-linear dynamics and non-Gaussian noise processes. Finally, we illustrate the resilience of the proposed solution under temporary GNSS denial.     

一种基于快速跳频的超宽带无线接入多址方式

超宽带技术是近年来美国联邦通信委员会批准为民用的高速短距离无线通信技术。对比分析了DS-UWB和TH—UWB2种单载波超宽带系统，在此基础上，为提高频谱利用率，在多径衰落和多用户信道中，给出了一种旨在解决多用户干扰的基于正交Costas序列快跳频的UWB—OFDM系统。