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An Adaptive Channel Estimation Technique in MIMO OFDM Systems

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Journal of Electronic Science and Technology of China 2008年第3期6卷 313-316页

作者： Pei-Sheng Pan bao-Yu zheng School of Communication ＆ Information Engineering University of Nanjing University of Posts and Telecommunications Nanjing 210003 China

In this paper, an adaptive channel estimation for MIMO OFDM is proposed. A set of pilot tones first are placed in each OFDM block, then the channel frequency response of these pilot tones are adaptively estimated by reeursive least squares （RLS） directly in frequency domain not in time domain. Then after the estimation of the channel frequency response of pilot tones, to obtain the channel frequency response of data tones, a new interpolation method based on DFT different from traditional linear interpolation method according to adjacent pilot tones is proposed. Simulation results show good performance of the technique.

关键词： Adaptive frequency domain MIMO squares. channel estimation OFDM recursive least

Dissolved oxygen sensor based on sol-gel matrix doped with tris(2,2'-bipyridine)ruthenium dichloride

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Journal of Chongqing University 2013年第1期12卷 11-15页

作者：熊小莉 TANG Yan zheng bao-zhan College of Chemistry and Materials Science Sichuan Normal University Institute of Chemical Engineering Sichuan University

To establish a immobilization method of oxygen sensitive dye, a dissolved oxygen sensor based on a sol-gel matrix doped with ruthenium complex ([Ru(bpy)3]2+) as the oxygen-sensitive material is reported. The results indicate that the I0 /I100 value of the [Ru(bpy)3]2+-doped in tetraethylorthosilane (TEOS) composite films are estimated to be 10.6, where I0 and I100 correspond to the detected fluorescence intensities in pure nitrogen saturated water and pure oxygen saturated water, respectively. Also, the Stern-Volmer plot shows a very good linearity at low dissolved oxygen concentrations. The response time of the composite films is 5 s upon switching from nitrogen saturated water to oxygen saturated water and 10 s from oxygen saturated water to nitrogen saturated water. The dissolved oxygen sensors based on the ruthenium complex/TEOS composite films exhibit greater sensitivity, stability and faster response time as compared to the existing ones. Furthermore, the thin films possess greatly minimized dye leaching effect.

关键词： dissolved oxygen sensor ruthenium complex sol-gel

Motion Compensation for Airborne SAR

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Motion Compensation for Airborne SAR

SIMPLIFIED LATTICE REALIZAT ION OF FIR DIGITAL FILTERS

2000年第16届世界计算机大会

作者： Cao Fuxiang bao zheng Yuan Jianping Key Laboratory for Radar Signal Processing Xidian University Northwestern Polytechnical University

＜正＞To obtain high resolution image from an airborne Synthetic Aperture Radar（SAR）,it is essential that accurate motion compensation be applied to the radar returns to reduce image degradation,caused by spurious motion of antenna phase center（APC）,to an acceptable level. This paper describes a new SAR Motion Compensation System（SARMCS）,which includes a airplane MENS（Master Inertial Navigation System） and a GPS receiver located near the mass center of the aircraft,a slaved low cost strapdown IMU（Inertial Measurement Unit） mounted on the antenna structure. The performance requirements of the SARMC are described,the configuration of SARMCS itself is outlined,and finally simulation results are given in the following sections.

关键词： SAR motion Compensation GPS IMU Kalman Filter

来源： cnki会议评论

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Journal of Electronics(China) 1989年第1期6卷 10-18页

作者：张玉洪保铮 Xidian University Xi'an

This paper suggests a simplified lattice structure for implementing FIR digital filters,which halvesthe hardware requirements of a conventional lattice *** conversion algorithms between directrealizations and the simplified lattice forms are ***,the algorithms for linear phase FIR fil-ters are *** principal results are illustrated by a practical example.

关键词： Lattice structure Digital filter FIR

一种新的机载条带式SAR沿航向运动补偿方法

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电子学报 2005年第3期33卷 459-462页

作者：黄源宝保铮周峰西安电子科技大学雷达信号处理重点实验室陕西西安710071

提出了一种新的机载条带式SAR沿航向运动误差的补偿方法 .它不用插值 ,所以节省了运算量、避免了插值带来的图像质量下降 ,因而对机载SAR系统的实时成像有好的应用前景 .理论分析、仿真和实测数据成像证明了该方法的正确性和有效性 .

关键词：合成孔径雷达条带式运动补偿

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低分辨雷达成像定标算法性能分析

西安电子科技大学学报 2000年第6期27卷 677-681页

作者：姜正林保铮西安电子科技大学雷达信号处理国家重点实验室陕西西安710071

确定低分辨雷达目标横向成像的距离定标 (横向距离因子 ) ,是正确获取目标横向距离像和进行雷达目标识别的一个前提 .根据合成阵列以及干涉SAR(INSAR)的原理 ,利用两个水平方向放置的天线 ,通过对两个天线所成一维横向距离像进行比相 ,... 详细信息

确定低分辨雷达目标横向成像的距离定标 (横向距离因子 ) ,是正确获取目标横向距离像和进行雷达目标识别的一个前提 .根据合成阵列以及干涉SAR(INSAR)的原理 ,利用两个水平方向放置的天线 ,通过对两个天线所成一维横向距离像进行比相 ,完成目标的横向定标 .通过理论及性能分析和仿真实验证明 ,该方法是正确和有效可行的 .

关键词：逆合成孔径雷达横向距离定标相干积累干涉

Generating dense and super-resolution ISAR image by combining bandwidth extrapolation and compressive sensing

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Science China(Information Sciences) 2011年第10期54卷 2158-2169页

作者： QUAN YingHui ,ZHANG Lei,GUO Rui,XING MengDao & bao zheng National Key Lab for Radar Signal Processing,Xidian University,Xi’an 710071,China National Key Lab for Radar Signal Processing Xidian University Xi’an China

Recent developing compressive sensing (CS) theory indicates that it is possible to obtain precise recovery of a sparse signal from very limited measurements,which provides a new way for data acquisition and signal processing as nature signals usually involve some degree of *** this paper,we present an algorithm for inversed synthetic aperture radar (ISAR) imaging with super resolution by combining CS and bandwidth extrapolation (BWE) *** ISAR imaging,the backscattering field of target is usually contributed by a few strong scattering centers,whose number is much less than that of image ***,CS is intuitively suitable for constructing super resolution ISAR *** to CS theory,the number of extracted dominating scatterers relies on the signal length,which indicates that if only limited data is available,it is difficult to generate dense ISAR image robustly by CS,and some signal components tend to *** soften this constraint,BWE is combined with CS imaging to increase the degree of freedom of signal while preserving its coherence.A refined CS-based formation for ISAR image-resolution enhancement is then *** real and simulated data experiments are performed to evaluate the proposed approach,and an example of using this technique demonstrates the enhanced image resolution in application of maneuvering target imaging.

关键词： inverse synthetic aperture radar (ISAR) compressive sensing (CS) bandwidth extrapolation (BWE) super resolution

Kirschner wire migration from the right second rib to the right ventricle： a case report

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Chinese Journal of Traumatology 2013年第5期16卷 292-294页

作者： WANG Song bao zheng LUO Ling-fu Department of Thoracic Surgery Affiliated NanhuaHospital University of South China Hengyang 421002China Department of Cardiac Surgery Second XiangyaHospital Central South University Changsha 410011China

Migrations of orthopedic wires to car- diovascular system are uncommon and rarely reported. We report a case of right ventricle embolization with the Kirschner wire that was used for right 2nd rib osteosynthesis 2 years and 8 months previously in a 50-year-old man. The patient was asymptomatic and migration of the Kirschner wire was discovered by routine chest X-ray. An 8 cm-long Kirschner wire was successfully retrieved from the right ventricle. The treatment strategy for Kirschner wire removal from right ventricle is discussed.

关键词： Bone wires Heart ventricles Rib fractures

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我国捐赠税收制度研究

兰州大学学报（社会科学版） 2009年第3期37卷 82-90页

作者：史正保兰州商学院法学院甘肃兰州730020

我国现行税法关于捐赠税收制度还存在着一些缺陷和不足,严重影响了我国公益捐赠事业的发展。从我国关于捐赠的税收立法规定出发,分析了我国目前关于捐赠税收制度存在的问题,进而提出了完善捐赠税收制度的建议,以促进我国公益捐赠事业的... 详细信息

我国现行税法关于捐赠税收制度还存在着一些缺陷和不足,严重影响了我国公益捐赠事业的发展。从我国关于捐赠的税收立法规定出发,分析了我国目前关于捐赠税收制度存在的问题,进而提出了完善捐赠税收制度的建议,以促进我国公益捐赠事业的发展。

关键词：捐赠税收制度纳税人公益性捐赠税收优惠制度