多核系统中NoC通讯架构的关键技术

多核处理器已经成为处理器的主流,并发展成为各种通信与媒体应用的主流处理平台。通讯结构是多核系统中的核心技术之一,核间通信的效率是影响多核处理器性能的重要指标。目前有3种主要的通讯架构:总线系统结构、交叉开关网络和片上网络。总线结构设计相对方便、硬件消耗较少、成本较低;交叉开关是适合用于构建大容量系统的交换网络结构;而片上网络是更高层次、更大规模的片上网络系统,目前可以解决多核体系结构问题,是多核系统最有前途的解决方案之一。文中在分析了NoC结构的基本原理、系统结构和功能的同时,也提供了部分单元的设计实现。     

达芬奇异构多核处理器核间通信技术研究

针对目前通用的达芬奇异构多核处理器,研究了其ARM核、DSP核以及视频协处理器之间的通信与协作机制.在分析多核处理器核间通信原理的基础上,研究了TMS320DM816x系列达芬奇异构多核处理器的核间通信技术,详细阐述片上核间互联结构与核间通信软件的实现.最后基于SysLink底层通信模块设计了多路高清音视频应用系统,对核间通信进行验证.系统可充分发挥各处理核的性能,实现了各核间的高效协作.     

一种DSP和通用CPU一体化的处理器架构及其4核实现

提出了一种DSP和通用CPU一体化的处理器架构,并完成了一款基于该架构的同构4核处理器设计和流片验证.该处理器基于VLIW结构,支持自主定义的DSP指令系统,兼容现有通用的MIPS 4KC处理器指令集,支持最大8个指令通道的并行发射.处理器在不改变CPU的指令编码以及执行顺序的前提下,实现了芯片结构上的DSP和CPU执行处理的一体化,适合在统一的平台上同时完成宽带通信和多媒体的信号和协议处理的嵌入式应用开发.处理器内核通过自主定义的DSP指令字中前后并行标识位和一条专用的前导paralink指令实现了DSP与CPU指令的并行发射.在4核处理器的同构架构上,采用了全局读局部写的多核间片上数据存储策略,在控制硬件开销的基础上实现片上数据的共享.仿真和流片验证结果表明,所提出的DSP和CPU一体化处理器架构可行,在宽带通信和多媒体等嵌入式应用上具有优势.     

飞思卡尔推出QorIQ通信平台 首款八核微处理器行业最高标准

飞思卡尔半导体推出QorIQ P4080多核处理器，一个旨在为嵌入式多核空间中的性能、功效和编程性设定新标准的非常先进的八核通信处理器。P4080多核处理器是飞思卡尔新QorIQ平台的标志性成员，基于45纳米处理技术。它集成了增强的Power Architecture内核、三级缓存分层、创新CoreNet片上结构和数据路径加速，可在最大30W的功率电路内提供卓著性能。     

NoC_MPSim:基于片上网络通信架构多核仿真平台

实现了一个用于探索基于片上网络通信架构多核系统设计空间的可配置仿真平台--NoC_MPSim.该平台包含处理器工具链、平台自动化配置脚本以及一个包含处理器、网络适配器以及多种路由器的RTL模型库,可根据用户输入的系统配置信息自动生成周期精确的多核仿真系统.针对片上网络通信架构的特征,定义了基于该通信架构的多核系统的高层次通信抽象模型,并借鉴并行机中的消息传递机制,提出了一种可有效隐藏网络乱序的并行编程模型及其通信原语,并完成其所需要的软\硬件建模.应用提出的编程模型,实现了MUSIC算法基于四核仿真系统的分布式并行计算,并经实验得到该并行MUSIC算法在该系统中加速比可达2.6.     

多核处理器核间高速通讯架构的研究

多核处理器使得并行系统的结构日益复杂,已经成为处理器的主流,并发展成为各种通信与媒体应用的主流处理平台.通讯结构是多核系统中的核心技术之一,核间通信的效率是影响多核处理器性能的重要指标.目前有三种主要的通讯架构:总线系统结构、交叉开关网络和片上网络.总线结构设计相对方便、硬件消耗较少、成本较低,交叉开关是适用于构建大容...     

基于Octeon多核网络处理器的IPv6联动IPS研究与设计

对基于Octeon多核网络处理器的新一代IPv6高速网络联动入侵防御系统进行研究,设计了新型联动入侵防御原型.系统基于Octeon多核的高速处理,并结合了IPv6网络中入侵的新特点.在基于入侵检测规则库规则匹配技术的基础上,运用新型的协议分析技术和基于流的检测技术,在Octeon多核间分配控制层与数据层的不同执行,采用命名块机制进行多核间通信,通过数据层核向控制层核的反馈,实现了流处理及协议分析模块与控制模块的高速联动.系统实现了Gbps级的高速入侵检测与联动防御处理.     

多核处理器核间的通信研究与实现

针对多核处理器的特点提出一种新型的异构多核DSP处理器结构。主处理器为通用处理器,作为控制密集型处理器核用于系统管理和控制;8个DSP作为计算密集型处理器核,用于大信息量融合计算。详细设计8个DSP之间的No C互连结构。首先采用2×4 2D Turos结构进行单个路由节点结构的设计,包括数据包格式、路由和仲裁设计;其次对路由节点进行编码、路由算法设计和确定节点路由方向。该结构具有总线局部通信带宽高的优点,采用No C的易扩展性和No C在各DSP之间通信的并行性使系统规模易于扩展并满足大批量数据传输要求。最后通过仿真实验,验证了该设计的有效性,为后续多核处理器的设计与实现打下坚实的技术基础。     

一种通用片上网络适配器的设计与实现

随着片上网络的结构和方法的提出,迫切需要一种接口电路来实现处理器,计算单元或者IP核与片上网络之间的通信.文中研究了不同时钟域之间进行数据传送的通信协议,详述了一种应用于片上网络的通用网络适配器的设计方法,并在Altera的stratixⅢ系列FPGA开发板上进行了验证.     

基于FPGA和ASIC实现的不同路由器结构的MPSoC比较

随着工艺特征尺寸的缩进,为了进一步提高数据处理速度,多核片上系统(MPSoC)成为一种必然的选择。片上网络(NoC)作为多核片上系统的通信部分,其设计影响了整个系统的性能。本文研究了2种不同的片上网络设计,探讨了路由器结构的改变对MPSoC性能的影响。对于采用低延迟优化设计的路由器,通过ModelSim仿真得到数据帧的最优传输延迟减少了6倍。同时,分别完成了该MPSoC的FPGA和ASIC实现,基于实现结果定量分析了在0.13 μm工艺尺寸下2种实现方式的面积和延时差距。结果表明,FPGA实现与ASIC实现的面积比率大约为29~33:1,延时比率大约为4.5~7.5:1。     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

中国建立EB级存储实验室,致力云计算应用(英文)

正With the support of 863 programs,Sugon Information Industry Co.,Ltd.,set up a dawning EB-class storage laboratory to address massive data storage requirements and largescale cloud computing demonstration applications.The Dawning EB-class cloud storage system adopts advanced fault-tolerant architecture,efficient data fault-tolerant algorithms with user authentication and data encryption policies to deal with the"lost""wrong"and"stolen"problems of data for ensuring the reliability and safety of the EB-class storage system in the public network application environments.The Dawning EB-class Storage Laboratory taking advan-