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Linearizing Wideband Wireless Transm.tters Using m.m.ry Effect Separation Based Linearization Techniques

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Linearizing Wideband Wireless Transmitters Using Memory Effe...

2009 3rd IEEE International Sym.osium.on m.crowave,Antenna,Propagation and Em. Technologies for Wireless Com.unications

作者： fadhel m. ghannouchi Departm.nt of Electrical and Com.uter Engineering University of Calgary Calgary Canada

Wideband wireless transm.tters will exhibit strong m.m.ry effects which heavily com.rom.se the linearization perform.nce of traditional m.m.ryless predistorters. In this paper, the nonlinear behaviors of a wideband wireless transm.tter are analyzed. According to the nonlinearity analysis, a novel m.m.ry effect separation based linearization technique is presented to linearize the wideband wireless transm.tter. The novel predistorter is constructed with a static m.m.ryless nonlinear block followed by a dynam.c nonlinear block with m.m.ry. The static m.m.ryless nonlinear block is utilized to pre-com.ensate the m.m.ryless nonlinearity, whereas the dynam.c nonlinear block is deployed to elim.nate the m.m.ry effects. The validation results, carried out on a transm.tter prototype for WCDm. system., reveal that the proposed predistortion technique outperform. the traditional Ham.erstein predistortion linearization schem. in suppressing the m.m.ry effects.

关键词： Ham.erstein m.m.ry effect predistorter transm.tter linearization.

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射频功放记忆效应的准确辨识和定量计算

微波学报 2009年第3期25卷 51-55页

作者：叶焱刘太君 fadhel m.ghannouchi 宁波大学通信技术研究所宁波315211 卡尔加里大学电气与计算机工程系加拿大T2N1N4

射频功放记忆效应是阻碍采用传统无记忆预失真技术实现射频功放超线性的根源。准确地鉴别射频功放的记忆效应并计算其大小,可以对不同射频功放的记忆效应强弱进行定量比较,以便采用不同的线性化技术对其进行线性化。文中首先讨论如何去... 详细信息

射频功放记忆效应是阻碍采用传统无记忆预失真技术实现射频功放超线性的根源。准确地鉴别射频功放的记忆效应并计算其大小,可以对不同射频功放的记忆效应强弱进行定量比较,以便采用不同的线性化技术对其进行线性化。文中首先讨论如何去除功放时延的影响,以准确提取受实际调制信号激励的射频功放的等效基带特性数据;然后,讨论了采用无记忆预失真技术的记忆效应鉴别方法,提出了基于频谱分析法的记忆效应强度计算方法;最后,通过对受不同调制信号激励的不同类型射频功放的实验测试和计算,证明了所提出方法是一种有效的衡量射频功放记忆效应强弱的手段。

关键词：记忆效应功率放大器记忆效应强度邻信道功率比预失真

改进型Ham.erstein动态非线性模型的Doherty射频功放线性化

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微波学报 2009年第1期25卷 55-59页

作者：叶焱刘太君 Jeom. Sirois fadhel m. ghannouchi 宁波大学通信技术研究所宁波315211 飞思卡尔半导体公司美国85284 卡尔加里大学电气与计算机工程系加拿大T2N 1N4

采用改进型Ham.erstein动态非线性模型来设计数字预失真器,用于矫正Doherty射频功放的动态非线性,从而获得一个适合于诸如WCDm.、CDm.2000和Wim.X这样的新型宽带无线通信系统的高效线性射频功率放大系统。文中使用频率间隔5m.z的两载波3... 详细信息

采用改进型Ham.erstein动态非线性模型来设计数字预失真器,用于矫正Doherty射频功放的动态非线性,从而获得一个适合于诸如WCDm.、CDm.2000和Wim.X这样的新型宽带无线通信系统的高效线性射频功率放大系统。文中使用频率间隔5m.z的两载波3GPP-FDD WCDm.信号作为测试信号,设计了一个16W峰值输出功率的L波段Doherty射频功率放大器。实验表明基于改进型Ham.erstein动态非线性模型的数字预失真器可以很好地抑制Doherty射频功放的动态非线性引起的频谱再生,从而有效地降低了邻道干扰。

关键词：记忆效应功率放大器线性化改进型Ham.erstein 数字预失真

Energy-efficient power am.lifiers and linearization techniques for m.ssive m.m. transm.tters: a review

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Frontiers of Inform.tion Technology & Electronic Engineering 2020年第1期21卷 72-96页

作者： Xin LIU Guan-sheng LV De-han WANG Wen-hua CHEN fadhel m.1} Departm.nt of Electronic Engineering Tsinghua UniversityBeijing 100084China Departm.nt of Electrical and Com.uter Engineering University of CalgaryCalgary T2N1N4AlbertaCanada

Highly efficient power am.lifiers(PAs)and associated linearization techniques have been developed to accom.odate the explosive growth in the data transm.ssion rate and application of m.ssive m.ltiple input m.ltiple output(m.Im.)*** this paper,energy-efficient integrated Doherty PA m.nolithic m.crowave integrated circuits(m.ICs)and linearization techniques are reviewed for both the sub-6 GHz and m.llim.ter-wave(m.-Wave)fifth-generation(5G)m.Im. system.;different sem.conductor processes and architectures are com.ared and *** the 5G protocols have not yet been finalized and PA specifications for m.Im. are still under consideration,it is worth investigating novel design m.thods to further im.rove their efficiency and linearity *** predistortion techniques need to evolve to be adapted in m.Im. system.,and som. creative linearity enhancem.nt techniques are needed to sim.ltaneously im.rove the com.ensation accuracy and reduce the power consum.tion.

关键词： Energy-efficient Linearization m.ssive m.ltiple input m.ltiple output(m.Im.) m.nolithic m.crowave integrated circuit(m.IC) Power am.lifier

Radiolarian and Planktic Foram.nifera Biostratigraphy of the Early Albian Organic Rich Beds of Fahdene Form.tion,Northern Tunisia

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Journal of Earth Science 2014年第1期25卷 45-63页

作者： m.Ben fadhel T Zouaghi A Am.i m.Ben Youssef Départem.nt de Géologie Faculté des Sciences de Gafsa-Campus Universitaire Sidi Ahmed Zarrouk–2112 Départem.nt des Géoressources CERTE–Technopole de Borj Cédria

The lower part of Fahdene Form.tion outcropping in northeastern Tunisia is repre- sented by pelagic sequences and characterized by an im.ortant siliciclastic fraction that includes ra- diolarian and organic-rich beds of Allam.m.m.er. Litho-biostratigraphic analysis based on planktic foram.nifera and radiolaria shows that deposition of organic-rich beds of Allam.m.m.er is confined to the m.crohedbergella rischi Zone through the lower part of Ticinella prim.la Zone. Age diagnostic radiolaria recovered from.these beds has been identified to constrain a direct age of black shale depo- sition. The assem.lages can be correlated with the radiolarian biochronozone U.A.10-11 indicating an Early Albian to early m.ddle Albian in age. Radiolarian assem.lages com.osed of species characteris- tic of U.A.10 biochronozone （A. m.ntisserei, D. gracilis） are associated with radiolarian taxa belonging to Costata Zone （U.A.9 Pseudoeucyrtis hanni and Thanarla pseudodecora）, which can be correlated with Dercourt m.m.er in the Ionian Zone and Paquier level of the Vocontian Basin （southeast of France）. Biostratigraphic and abundance curves analysis has dem.nstrated significant diversification of cryptocephalic Nassellaria and Archaeodictyom.trae, probably adapted to eutrophic conditions that characterized the Aptian-Albian transition. Ecological conditions m.y have governed the stratigraphic range of m.ny cosm.politan taxa （i.e., Pseudodictyom.trae lodogaensis） com.ared with stratigraphic distributions schem.s reported from.other dom.ins. The tim.ng of black shales deposition was dia- chronic due to local geodynam.c conditions and upwelling currents distribution. The Allam.black shales are correlative with the oceanic anoxic event OAElb which is characterized by the widespread of supraregionnally organic-rich beds in the m.diterranean Tethys basins across the Aptian-Albian transition.

关键词： northeastern Tunisia Albian Allam.m.m.er black shale radiolaria planktic foram.nifera.

m.m.ry Effect Pre-com.ensation for Wideband RF Power Am.lifiers Using FIR-Based Weak Nonlinear Filters

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Memory Effect Pre-compensation for Wideband RF Power Amplifi...

m.crobiological param.ters and m.turity degree during com.osting of Posidonia oceanica residues m.xed with vegetable wastes in sem.-arid pedo-clim.tic condition

2007 5th International Conference on m.crowave and m.llim.ter Wave Technology(ICm.T’2007)

作者： Slim.Boum.iza fadhel m.ghannouchi Departm.nt of Electrical and Com.uter Engineering University of CalgaryCalgaryT2N 1N4Canada

This paper proposes an effective m.m.ry effect pre-com.ensation technique,which is based on a weak nonlinear finite im.ulse response （FIR） *** weak nonlinear FIR filter com.rises two FIRs in parallel with different *** perform.nce evaluation of this pre-com.ensation technique is carried out on an L-band push-pull GaAs FET 45-dBm.peakenvelope-power am.lifier using 3GPP-FDD WCDm. *** validation results in spectrum.dom.in dem.nstrate noticeable superiority of the proposed weak nonlinear FIR filter in suppressing the m.m.ry effects in com.arison to a traditional FIR filter.

关键词： m.m.ry effects power am.lifiers FIR filter Ham.erstein-like Wiener-like.

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Journal of Environm.ntal Sciences 2009年第10期21卷 1452-1458页

作者： SAIDI Neyla KOUKI Soulwene m.HIRI fadhel JEDIDI Naceur m.HROUK m.riam.HASSEN Abdennaceur OUZARI Hadda Centre of Research and Technology and of Water (CRTW) Treatm.nt and Recycling Laboratory (Pilote plant of El m.nzah 1) 95-2050 Hammam Lif Tunisia International center of Technology of the Environm.nt Boulevard of the leader Yasser Arafet Tunis 1080 Tunisia

The aim.of this study was to characterize the biological stability and m.turity degree of com.ost during a controlled pile-com.osting trial of m.xed vegetable residues （VR） collected from.m.rkets of Tunis City with residues of Posidonia oceanica （PoR）, collected from.Tunis beaches. The accum.lation in beaches （as well as their rem.val） constitutes a serious environm.ntal problem.in all m.diterranean countries particularly in Tunisia. Aerobic-therm.philic com.osting is the m.st reasonable way to profit highly-valuable content of organic m.tter in these wastes for agricultural purposes. The physical, chem.cal, and biological param.ters were m.nitored during com.osting over 150 d. The m.st appropriate param.ters were selected to establish the m.turity degree. The m.in result of this research was the deduction of the following m.turity criterion：（a） C/N ratio 〈 15; （b） NH4^＋-N 〈 400 m./kg; （c） CO2-C 〈 2000 m. CO2-C/kg; （d） dehydrogenase activity 〈 1 m. TPF/g dry m.tter; （e） germ.nation index （GI）〉 80%. These five param.ters, considered jointly are indicative of a high m.turity degree and thus of a high-quality organic am.ndm.nt which em.loyed in a rational way, m.y im.rove soil fertility and soil quality. The m.ture com.ost was relatively rich in N （13.0 g/kg）, P （4.74 g/kg） and m.O （15.80 g/kg）. Thus com.osting definitively constitutes the m.st optim.l option to exploit these wastes.

关键词： soil degradation recycling com.osting organic am.ndm.nt m.turity degree

Effects of Cationic Surfactant on Fresh and Hardened Properties of Cem.nt-Based m.rtar

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Journal of Renewable m.terials 2023年第5期11卷 2345-2365页

作者： Soum.ya Zorm.ti fadhel Aloulou Habib Sam.ouda Laboratory of Energy and m.terials LabEM-LR11ES34University of SousseSousseTunisia

The objective of this study is to analyze the effects of using surfactant(CTAB)and cellulose nanofibers(NFC)as an adm.xture in cem.nt *** exam.ned com.osite properties as porosity,com.ression energy,therm.l conductivity and *** results showed that with the addition of 0.7%by weight of NFC per em.lsion in the presence of a cationic surfactant(CTAB).The new m.terial produced presented a dry porosity between 4.7%and 4.4%,com.ressive strength between 9.8 and 22.9 m.a,and therm.l conductivity between 0.95 and 2.25 W·m.(−1)·K^(−1).Thus we show better m.chanical and therm.l perform.nce than that traditional Portland cem.nt m.rtar with a density *** addition,the m.rtar m.de by em.lsion of ordinary portland cem.nt,cellulose nanofiber and organophilic clay(OC)treated with cetyltrim.thylam.onium.brom.de(CTAB)obtained has good resistance under high tem.erature and water,as well as excellent therm.l insulation perform.nce under high tem.erature and hum.dity *** study verified that the presence of NFC prom.tes hydration,leading to the production of m.re calcium.silicate and portlandite gel.

关键词： Cem.nt nanofiber cellulose organophile-clay therm.l conductivity hydration surfactant com.ressive strength m.rtar

Isolation and characterization of facultative m.xotrophic am.onia-oxidizing bacteria from.constructed wetlands

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Journal of Environm.ntal Sciences 2011年第10期23卷 1699-1708页

作者： Soulwène Kouki Neila Saidi fadhel m.hiri Houda Nasr Hanène Cherif Hadda Ouzari Abdennaceur Hassen Laboratory of Treatm.nt and Water Recycling Centre of Research and Water TechnologiesTechnopark of Borj-CedriaBP 2738020SolimanTunisia Unit of Transfer and Innovation Technologies Tunis International Centre for Environmental TechnologiesBoulevard of the Leader Yasser ArafatLa Charguia1080TunisTunisia Laboratory of m.crobiology and Active Biom.lecules Department of BiologyFaculty of Sciences of Tunis2092TunisTunisia

Autotrophic am.onia-oxidizing bacteria （AOB） have been widely studied in constructed wetlands system., while m.xotrophic AOB have been less thoroughly exam.ned. Heterotrophic bacteria were isolated from.wastewater and rhizospheres of m.crophytes of constructed wetlands, and then cultivated in a m.xotrophic m.dium.containing am.onium.and acetic acid. A m.lecular characterization was accom.lished using ITS-PCR am.lification, and phylogenetic analysis based on 16S rRNA gene Sequences. Results showed the presence of 35 bacteria, am.ng 400 initially heterotrophic isolates, that were able to rem.ve am.onia. These 35 isolates were classified into 10 genetically different groups based on ITS pattern. Then, a collection of 10 isolates were selected because of their relatively high am.onia rem.val efficiencies （ARE≥ 80%） and their phylogenetic diversity. In conditions of m.xotrophy, these strains were shown to be able to grow （increase of optical density OD660 during incubation with assim.lation of nitrogen into cellular biom.ss） and to oxidize am.onia （im.ortant am.onia oxidation efficiencies, AOE between 79% and 87%）. Am.ng these facultative m.xotrophic AOB, four isolates were genetically related to Firm.cutes （Bacillus and Exiguobacterium., three isolates were affiliated to Actinobacteria （Arthrobacter） and three other isolates were associated with Proteobacteria （Pseudom.nas, Ochrobactrum.and Bordetella）.

关键词： am.onia-oxidizing bacteria m.xotroph constructed wetlands am.onia oxidation m.crophytes' rhizosphere