OFDM系统中FFT处理器的版图设计

用Astro工具设计FFT处理器版图流程.在设计FFT处理器版图过程中,采用新的电源网络设计方法进行电源/地Pad数量、电源环和电源条设计,采用布线前设定高层跳线方式和布线后插入保护二极管方式消除天线效应,通过整个版图设计过程防止串扰效应实现串扰不超过设定的阈值,并对布局阻塞违规和布线违规提出解决办法.实现了满足时序和制造工艺要求的FFT处理器版图,达到项目设定的各项性能指标要求.     

实时可重配置FFT处理器的ASIC设计

设计一种能够完成4,16,64,256或1 024点复数快速傅里叶变换(FFT)处理器芯片.16,64点运算采用基-4级联流水线结构,256,1 024点采用二维运算结构,数据采用块浮点表示.使用Synopsys公司的综合及布局布线工具在SMIC CMOS 0.18 μm工艺上进行ASIC实现.该处理器芯片在100 MHz时钟频率连续工作时,处理一组1 024点FFT序列需要24.8 μs,每隔10.24 μs输出一组1 024点运算结果.该处理器芯片已应用于某宽带数字接收机中.     

用于TD-SCDMA下行链路联合检测的2×2 MIMO FFT处理器设计

为了在TD-SCDMA移动终端实现高效联合检测,设计了一个用于2×2 MIMO系统的64/128点FFT处理器.设计的FFT处理器基于R2SDF的流水线结构,采用乘法器共享的电路结构,适合处理2路MIMO系统,在满足系统数据吞吐率的同时,节省了信号处理的硬件开销.设计采用Xilinx公司的Virtex4进行综合验证,同时采用SMIC13工艺综合,在50 MHz的时钟下,功耗估计为8.3 mW,实现了低开销的电路设计.     

全流水FFT处理器的VLSI设计与实现

提出了一种适用于OFDM系统的快速全流水FFT处理器结构.考虑时域抽取(DIT)和频域抽取(DIF)算法的有限字长效应,采用DIF算法.首先对FFT碟形变换的复乘法进行简化,然后提出相应的流水线碟形处理单元(BPE),最后采用0.13μm1.08 V CMOS工艺实现了64点基2 DIF FFT处理器.综合结果显示,该处理器能够工作在200 MHz,面积和功耗分别为2.9 mm2和15 mW.提出的全流水FFT处理器能够广泛应用于WALN、DVB-T、ADSL以及其它基于OFDM的多载波系统.     

网络综合布线系统的工程设计

随着信息技术的普及应用,各种智能化建筑逐渐成为普通大众的工作、生活必需品．智能化建筑的建设,综合布线系统是基础,它为信息资源的传递提供了物理通道,是现今和未来计算机网络和信息系统的基础支撑环境．文章从网络综合布线系统建设的规划、设计入手,研究网络综合布线系统建设的工程设计方法和技术,并结合《综合布线系统工程设计规范》给出完整的综合布线工程设计要点和流程,对网络综合布线工程建设具有实际指导意义．     

高吞吐率可配置FFT处理器IP核的设计与VLSI实现

针对一种新型的OFDM系统算法,设计了一款具有高吞吐率可配置的FFT处理器IP核.在现有算法的基础上,提出了一种优化的设计架构,并对各个功能模块特别是存储单元、复数乘法器和控制逻辑进行了优化设计.通过基于Verilog HDL的参数化模块设计和模块复用技术,最大限度地提高数据吞吐率,实现了FFT处理器点数的可配置功能.Vertex-Ⅱ Pro FPGA验证结果表明,对于256点定点16位符号数复数FFT运算,该FFT处理器最高工作频率为106 MHz,系统数据吞吐率达到了51.3 MS/s,延时仅为255个时钟周期.     

局部流水FFT处理器地址产生和系数存储负载的设计（英文）

快速傅立叶变换(FFT)是数字信号处理中一种非常重要的算法,局部流水结构是一种实现嵌入式实时FFT处理器设计的有效结构.针对局部流水FFT处理器,主要推导了基于基16FFT第一地址生成公式的转换,并与我们提出的地址产生方法、操作数地址生成方法、系数存储负载策略及系数地址生成方法进行了对比分析.为有效解决局部流水结构FFT处理器的数据流控制问题提供参考.     

一种应用于DC-OFDM系统的FFT处理器设计

设计了一种应用于双载波正交频分复用(DC-OFDM)无线通信系统的高速、低功耗快速傅里叶变换(FFT)处理器.为降低传统并行架构带来的硬件实现开销,提出了一种新型的结合FFT分解的多路并行架构,有效减少了实现所需的乘法器和加法器数目,在提高处理器数据吞吐率的同时,进行了芯片面积的优化.另外,采用提出的处理单元实现不同的基运算,并对基-2、基-22、基-23、基-24不同架构下的定点FFT运算所需的硬件开销进行定量分析,以选择最优的基结构.最后,介绍了旋转因子乘法器的设计.设计实现的128点FFT处理器采用SMIC 0.13μm CMOS工艺,芯片面积为1.44 mm2,最大数据吞吐率达到1GS/s,在典型工作频率500MS/s下的功耗为39.5mW.与现有其他128点FFT处理器相比,减小了面积,节约了功耗.     

基于ASIC的128点FFT处理器的设计

所研究的芯片是128点定点FFT处理器,该处理器主要应用于超宽带无线通信系统.采用一种适合于128点快速傅里叶变换(FFT)的混合基-22/2的按频率抽取算法,并在此基础上设计一种并行运算与流水线结构相结合的硬件系统.详细描述了系统状态机的设计,最终实现了一个满足时序和设计工艺要求,达到了以下指标:工作频率66 MHz,芯片面积3.54 mm2,功耗为71.6 mW的高性能的FFT的IP处理器核.     

基于超标量处理器的高效FFT映射方法

针对超标量处理器的结构特点,研究新的映射方法,实现高效FFT运算.对现代超标量结构处理器进行建模,分析FFT算法在其上执行情况,得出内存访问是FFT算法执行的关键点.并进一步对FFT的内访问过程进行建模分析,最终实现了一种基于cache优化的高效FFT映射方法,该方法将FFT进行拆分实现,充分发挥了cache的作用,进而提高了处理性能.最后在ADI公司的TS201数字信号处理器上,以该映射方法为指导实现了基2FFT算法,实验结果显示在处理点数超出cache容量时,本映射方法可以大幅度提高处理性能.      

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the