Millimeter-Wave Ultra-Wideband Bandpass Filter Employing Dual-Mode Ring Resonators Fed by Step-Impedance Coupled Lines

This paper presents a novel millimeter-wave ultra-wideband (UWB) bandpass filter (BPF) based on microstrip dual-mode rectangular ring resonators. In order to get strong coupling between the input/output line and the dual-mode ring resonators, a step-impedance parallel-coupled structure is adopted for the design of the filter. On the other hand, transmission zeros are produced by the dual-mode resonator. As a consequence, the filter has low insertion-loss in its passband, sharp attenuation in its lower and upper stopbands and very wide stopbands. As an example, a filter with two dual-mode ring resonators is designed and fabricated. The measured frequency property of the fabricated filter shows good agreement with the simulated response.     

A highly miniaturized LTCC dual-band UWB filter using independent transmission zeros and lowpass filters

In this paper, a compact dual-band ultra-wideband (UWB) filter has been newly designed and fabricated for 3.1–4.75 GHz and 6.0–8.5 GHz UWB system applications by embedding all passive lumped elements into low temperature co-fired ceramic (LTCC) substrate. In order to reduce its size/volume and prevent parasitic electromagnetic (EM) coupling between the embedded passive elements, it was newly designed by using a modified 3rd order Chebyshev filter topology and J-inverter transformation technology. Moreover, in order to completely reject the wireless local area network (WLAN) bands of 2.4 GHz and 5.15 GHz, an independent transmission zeros technology was applied. For forming the higher passband, lowpass filters were also applied with two LC resonant circuits by using roll-off characteristics by independent transmission zeros. The measured insertion losses in the lower and upper passbands were better than 2.5 and 2.3 dB, respectively. Return loss and group delay were better than 8 dB and 0.61 ns, respectively in all the passbands. Independent transmission zeros that occurred at 5.17 and 5.42 GHz provided suppression of 22 dB at the WLAN band. The size/volume of the fabricated LTCC dual-band UWB filter was 3.65×2.35×0.65 (H) mm³.     

Triple band notched mushroom and uniplanar EBG structures based UWB MIMO/Diversity antenna with enhanced wide band isolation

Triple band-rejection MIMO/Diversity UWB antenna characteristics are described in this paper. Proposed antenna discards worldwide interoperability for microwave access WiMAX band from 3.3 to 3.6 GHz, wireless local area network WLAN band from 5 to 6 GHz and X-Band satellite downlink communication band from 7.1 to 7.9 GHz. Mushroom Electromagnetic Band Gap (EBG) structures helps to attain band notches in WiMAX and WLAN bands. Uniplanar plus shaped EBG structure is used for notch in X-band downlink satellite communication band. Decoupling strips and slotted ground plane are employed to develop the isolation among two closely spaced UWB monopoles. The individual monopoles are 90° angularly separated with stepped structure which helps to reduce mutual coupling and also contributes towards impedance matching by increasing current path length. Mutual coupling magnitude of more than 15 dB is found over whole UWB frequency range. The Envelope Correlation Coefficient is less than 0.02 over whole UWB frequency range.The variations in the notched frequency with the variations in mushroom EBG structure parameters are investigated.The antenna has been designed using FR-4 substrate and overall dimensions is (64 × 45 × 1.6) mm³.     

一种新型的双陷波特性超宽带天线的设计

提出了一种新型的具有双陷波特性的超宽带天线。该天线在2.8～12 GHz 的宽频带范围内电压驻波比(VSWR)小于2,通过在馈线上引出两个枝节获得了3.3～3.9 GHz 和5～6 GHz 的双陷波特性。通过调节枝节的长度和宽度可以很容易的调节阻带的位置和宽度。仿真和测试结果表明这种新型的天线具有良好的阻抗特性和辐射特性。该天线结构简单,易于加工,便于集成。文中给出了天线的设计以及不同参数对天线性能的影响     

基于地板开槽的陷波矩形渐变超宽带天线设计

提出了一种具有陷波特性的UWB天线.该天线用开槽的金属片作为辐射单元,并通过对地板的开槽处理减小了天线的尺寸.结合HFSS仿真工具,对天线结构进行理论优化并通过大量仿真对天线尺寸进行调整;设计出一种基于FR4介质的尺寸为25*15*1mm3的天线模型,并设计模型进行加工测量.该天线的工作频带覆盖3.1～10.6 GHz,并避免了3.5-GHz WiMAX,和5.825-GHz WLAN频段,适于超宽带无线通信系统的应用.     

Sharp-rejection microstrip bandpass filters with multiple transmission zeros

A simple design of a sharp-rejection microstrip bandpass (BPF) filter is presented. By creating multiple transmission zeros in the lower and upper stopbands, sharp rejection characteristics are obtained. The basic filter unit consists of a single parallel coupled-line section and an open-ended stub. A lossless transmission line model approach is used to derive the design equations for frequency responses and transmission zero positions. The bandwidths are controllable by the zero locations that in turn are controlled by varying the impedances of the configuration. To validate theoretical predictions, two prototype BPFs operating at lower band 2.4 GHz of WLAN are fabricated in microstrip form.     

一种针对超宽带标准的CMOS Gm-C低通滤波器

采用TSMC 0.18µm CMOS工艺实现了一种针对超宽带标准的264MHz低通滤波器。该4阶滤波器由两个二阶滤波器级联而成,相对于传统的二阶Gm-C滤波器设计,本文提出的二阶拓扑结构十分简单有效,节约了1个跨导单元,3个共模反馈网络,2个电容。因此芯片功耗和芯片面积大大降低,其他指标并无牺牲。测试表明该滤波器增益-0.5dB,频率响应实测结果与仿真吻合良好,芯片面积为〖0.06mm〗^2,远小于同类设计,在1.8V电源电压下,电流消耗为3mA。     

超宽带室内定位算法

为了解决室内密集多径环境下人员定位精度差这一问题,设计并实现了一种基于脉冲超宽带与能量检测接收机的信号到达时间估计算法。根据在IEEE802.12.4a标准室内家居环境下得到的超宽带信号,深入分析了信号的偏度、翘度与均方差特性。根据信号特性与信噪比之间的关系,算法能够实现高精度的信号传播时间估计。该算法充分考虑了积分周期与信号传播环境如视距与非视距对信号传播时间造成的影响。通过实验分析对比,该算法对信号传播时间估计具有更好的鲁棒性,目标运动速度和形变具有很好的鲁棒性,能够提供更高的精度。相较于阈值估计算法,该算法在低信噪比环境下最优能够提高10 ns的估计精度。     

一种具有简单微带线/共面波导结构的新型超宽带带通滤波器

本文提出了一种具有简单微带线/共面波导谐振器结构的新型超宽带带通滤波器,滤波器在通带的两侧具有两个传输零点。滤波器的输入、输出微带（开路）线之间具有耦合电容效应,该电容可以用来调整低端传输零点。微带（开路）线各自与共面波导谐振器可以形成两个串联电容,同时共面波导谐振器的一条短路枝节线形成了一个并联电感。微带开路线上的延伸微带枝节尺寸可以用来调整滤波器的上端传输零点。利用HFSS对该滤波器进行了仿真设计,详细的设计过程也一并给出。仿真表明滤波器的3dB带宽可以覆盖UWB的整个波段。     

Low power high gain CMOS LNA based on inverter cell and self-body bias for UWB receivers

A low-power low-noise amplifier (LNA) utilized a resistive inverter configuration feedback amplifier to achieve the broadband input matching purposes. To achieve low power consumption and high gain, the proposed LNA utilizes a current-reused technique and a splitting-load inductive peaking technique of a resistive-feedback inverter for input matching. Two wideband LNAs are implemented by TSMC 0.18 μm CMOS technology. The first LNA operates at 2–6 GHz. The minimum noise figure is 3.6 dB. The amplifier provides a maximum gain (S₂₁) of 18.5 dB while drawing 10.3 mW from a 1.5-V supply. This chip area is 1.028×0.921 mm². The second LNA operates at 3.1–10.6 GHz. By using self-forward body bias, it can reduce supply voltage as well as save bias current. The minimum noise figure is 4.8 dB. The amplifier provides a maximum gain (S₂₁) of 17.8 dB while drawing 9.67 mW from a 1.2-V supply. This chip area is 1.274×0.771 mm².     

A compact quasi-self-complementary dual band notched UWB MIMO antenna with enhanced isolation using Hilbert fractal slot

A compact ultrawideband multiple input multiple output antenna with dual band notch characteristics is proposed. The design utilizes the property of quasi-self-complementary monopoles to achieve a bandwidth that ranges from 2.2 GHz to 11 GHz. The design has a compact size of 30 mm × 41 mm × 1.59 mm. Two quasi-self complementary half circular monopoles are symmetrically arranged to obtain MIMO antenna. Bandnotch characteristics are obtained by adding parasitic strips of Levy's Fractal shape near the feed line. A Hilbert Fractal shaped slot is etched in the ground plane to enhance the isolation (|S₂₁| < −20 dB) throughout the operational bandwidth. The measured and simulated radiation patterns are in good agreement and is found to be stable throughout the ultrawideband. Moreover, the measured peak gain is found to be 4 dBi.     

一种槽线扰动的基片集成波导双模滤波器

该文提出一种新型小型化基片集成波导(SIW)双模滤波器。通过使用正交的输入输出馈线,和一段倾斜的槽线来扰动腔体的两个简并模,滤波器能产生两个传输零点(TZ)。采用该方法设计了一个中心频率为15 GHz,带宽为350 MHz的基片集成波导双模滤波器。该滤波器结构简单,成本低廉,易于加工。测试结果和仿真结果吻合,较好地验证了设计的可行性和有效性。     

Design and analysis of a super compact wide-band bandpass filter based on metamaterial resonators

In this paper, a novel compact wide-band bandpass filter (BPF) with a wide frequency range is presented. This filter consisting of a multi-mode resonator (MMR) and four metamaterial unit-cells benefits from a very compact size. Unit-cells based on a complementary spiral resonator (CSR) including a metallic via, improve both upper and lower stopband rejection and compensate the insertion loss (I.L) within the passband altogether. This wide-band filter presents a 3-dB bandwidth of 7.7 GHz, ranging from 3 GHz to 10.7 GHz and the Insertion loss is less than 0.7 dB over the passband. The measured results are in good agreement with both the full-wave electromagnetic simulation and the proposed circuit model results. The dimension of the fabricated filter is 0.128 λ × 0.1 λ (i.e., 5.6 × 4.4 mm²). This filter is considerably compact compared to the other wide-band bandpass filters with the same substrate.     

Effect and Compensation of Colored Timing Jitter in Pulsed UWB Systems

Ultra-wideband (UWB) systems impose a stringent requirement on the jitter performance of the system clock. So far, only the effect of white Gaussian timing jitter has been considered in the literature via numerical simulation. However, practical clocks commonly exhibit colored jitter. In this paper, we first investigate the bit error rate (BER) performance of a single-user binary pulse position modulation UWB system subjected to white and colored Gaussian jitter. It is shown that colored jitter degrades BER performance much more than white jitter, and the extent of degradation increases as the jitter bandwidth decreases. Motivated by this result, we then propose a new jitter compensation scheme to improve the BER performance under colored jitters with small jitter bandwidth, in which each information-bearing data symbol is coupled with a pilot symbol. The proposed scheme attempts to track first the jitter for the current pilot symbol by making use of the pulse-template correlation function. This information is then used together with the known clock jitter bandwidth and jitter root-mean-square (RMS) value to detect the current data symbol according to the maximum likelihood criterion. Simulation results show that the algorithm is effective in improving the BER performance for colored jitters with small jitter bandwidth. Lei Huang received the B.Sc. degree from Xi'an Jiaotong University, China, in 1993, the M. Sc. degree from South China University of Technology in 1996, and the Ph.D. degree from Victoria University of Technology (VUT), Australia, in 2003, all in Electrical Engineering. From 1996 to 1999, he was a Lecturer at South China University of Technology. From March 2003 to December 2005, he was with National University of Singapore as a Research Fellow. Since January 2006, he has been working in Panasonic Singapore Laboratories as an R & D Engineer. His research interests focus on physical layer aspects on wireless communication systems, especially CDMA, ultrawideband and millimeter wave communications.     

基于NSST域混合滤波与改进边缘检测PCNN的医学图像融合

针对传统医学图像融合中存在细节模糊、能量保存不完整、运行时间长等问题,提出一种基于非下采样剪切波(non-subsampled shearlet transform, NSST)域混合滤波与改进边缘检测脉冲耦合神经网络(pulse coupled neural network, PCNN)的医学图像融合方法。首先,利用YUV模型进行颜色空间转换分离出亮度通道Y,接着利用混合滤波分别对源核磁共振(magnetic resonance imaging, MRI)图像和亮度通道的灰度图像进行不同程度的增强。其次,采用NSST对增强后的MRI和亮度通道的灰度图像进行分解,得到高低频子带。低频子带使用修正的拉普拉斯能量和(weighted sum of eight-neighborhood-based modified Laplacian,WSEML)与局部区域能量加权和(weight local energy,WLE)的融合策略,高频子带采用改进边缘检测PCNN的融合策略。最后,经NSST逆变换得到融合图像。通过与其他6种融合方法对比,本文方法可以有效提高图像融合过程中的细节提取和能量保存,且...     

结构紧凑的高选择性宽带滤波器

摘 要：为实现结构紧凑和高选择性的宽带滤波器,在传统平行耦合线结构的基础上,作了适当改进,设计了三种结构新颖的三线耦合结构,均能够实现具有三个传输零点的宽带响应,且其中两个零点分别紧靠通带的上下边缘。加工并测试了基于其中一种结构的宽带滤波器,工作频率为2.6GHz,3dB相对带宽为63%,三个传输零点分别位于1.46GHz,3.77GHz和5.13GHz,介质基板采用Rogers 4003,厚度0.813mm。实测结果与仿真结果吻合良好,验证了结构的有效性。     

跳时脉位调制超宽带信号的功率谱密度分析

通过对时域信号的自相关时间均值函数做傅氏变换,推导出定周期跳时脉位调制超宽带脉冲序列的功率谱密度公式,形式更加简明;并分别在时域和频域进行仿真、分析,比较两种仿真结果,同时分析了跳时码周期和时延常数等参数对谱密度结构的影响,验证了推导结果与时域仿真的一致性。     

A compact planar ultra-wideband bandpass filter with multiple resonant and defected ground structure

A compact bandpass filter with dumbbell shape Defected Ground Structure (DGS) operating on ultra wide pass band (UWB – 3.1 to 10.6 GHz) is proposed. It is based on hybrid microstrip coplanar waveguide (dual sided metal) structure. A Multiple Resonant Structure (MRS) is constructed using coplanar waveguide (CPW) planar transmission line. The MRS makes the resonance using quarter wavelength and half wavelength open-ended CPW. The equispaced three resonances at lower (3.1 GHz), center (6.85 GHz) and higher edge (10.6 GHz) of the whole Ultra Wide Band is achieved using CPW MRS. To make the band as flat as possible, two more resonances are introduced using quarter wavelength microstrip patches on top of the commonly shared substrate, so the proposed filter becomes a five pole bandpass filter. A dumbbell shaped defected ground structure on either side of CPW MRS improves the return loss almost less than 20 dB over the whole UWB passband. The simulated results of proposed filter show good transmission response within passband and good rejection in out of the band. The simulated and measured results are very close to each other which proves the efficacy of proposed design.     

基于PDMS嵌入式超宽带天线设计

设计了一种以柔性材料聚二甲基硅氧烷(PDMS)为介质基片的超宽带(UWB)天线,其辐射单元由矩形和半圆环金属贴片组成,两部分结构由带状贴片连接,采用共面波导方式馈电。上述金属贴片嵌入在PDMS基片中间,用于人体通信的可穿戴系统。利用嵌入式结构,有效提高了天线的柔韧性和耐用性。为了更好地模拟天线在人体表面的工作环境,构建了包括皮肤、脂肪和肌肉的三层人体组织模型,满足人体安全的国际标准的最大天线比吸收率值为16.4 mW。最后对天线样品进行测试,结果表明天线总体性能稳定,阻抗带宽为5.39-10.33 GHz,实现了在医学机构使用的频段(5.725-5.875 GHz)要求。     

现代战争面临的高功率电磁环境分析

摘 要：本文综述了与电磁武器有关的高功率微波（HPM）、超宽带（UWB）、核电磁脉冲（HEMP）等高功率电磁辐射的主要参数及其传播规律；快上升沿电磁脉冲（FREMP）的主要参数及其传播规律与国外相关标准。对超宽带短脉冲电磁学的形成作了初步探讨，最后概略分析了超宽带电磁武器对防护工程的影响。