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1.
提出一种适于高空间分辨率大视场遥感相机的图 像高速高可靠传输系统。首先,分析了TLK2711的通信链路,提出 了基于同步控制字的高速串行传输策略;深入分析了噪声对传输可靠性的影响,进而提出(17,6)纠错编码算法,分析了纠错编码在大视场空间相机中应用的可行性; 最后,在某大视场TDICCD空间相 机样机上进行了系统测试。实验表明,本文系统可以实时传输80路高 量化数据,整个系统有 效数据吞吐率可达13.02Gbit/s;所 提出的(17,6)纠错编码算法纠错能力强,运算速度快,易于硬件 实现,每512Byte数据可纠正32bit的错误,提高了空间 相机高速串行传输的可靠性;系统在不同的传输速度下工作均表现出令人满意的效果。  相似文献   

2.
基于TDICCD空间相机图像模拟源系统设计   总被引:1,自引:1,他引:0       下载免费PDF全文
空间相机地面检测系统在投入使用之前,必须进行严格的自检功能测试。为了解决测试时与庞大的CCD相机系统对接造成的时间和物力资源浪费问题,本文结合TDICCD空间相机工作原理,设计了一种空间相机图像模拟源系统。本系统通过USB总线进行图像数据的下传,然后经SRAM缓存,并以流水线作业方式下载到FLASH中实现8通道图像数据的固存。并且可实现对相机行频大小、图像大小进行调整的功能,进而模拟不同型号空间相机。实验结果表明,该图像模拟源USB接口的下载速度可达到40 MB/s,空间相机地面检测系统显示的图像与上位机发送的图像一致,无数据丢失和误码的情况。该相机图像模拟源设计灵活,性能稳定可靠,适用范围广。  相似文献   

3.
SDRAM在大视场TDICCD空间相机中的应用   总被引:1,自引:0,他引:1  
该文针对大视场空间相机中需要缓存的图像数据量大的问题,对高速大容量存储器SDRAM控制技术进行了研究。首先,说明了大视场空间相机中图像数据缓存的需要,根据CCD图像数据和图像缓存工作特点,提出了基于行使能和刷新操作驱动和基于仲裁策略的SDRAM控制器。然后,为了提高图像数据缓存可靠性,针对缓存小数据量场合,提出了(6,8)纠错算法,针对缓存大数据场合提出了RS(143,127)和RS(142,126)码纠错算法。最后,在XX-X空间多光谱相机样机的成像系统上进行了试验验证。实验结果表明:两种控制器工作频率能够达到131 MHz,正常工作时,行使能驱动控制器存取速度达到127.08 MBps,仲裁策略控制器存取速度达到139.788 MBps,两种纠错算法在507 B/row内可以纠正32 b错误。基本满足空间相机中的稳定可靠、高效率的缓存图像数据要求。  相似文献   

4.
适于空间图像闪存阵列的非与闪存控制器   总被引:2,自引:2,他引:0  
提出一种适于空间应用的非与(NAND,not and)闪存控制器。首先,分析了空间相机存储图像的要求,说明了闪存控制器结构的特点。接着,分析了闪存数据存储差错的机理,针对闪存结构组织特点提出了一种基于BCH(Bose-Chaudhuri-Hocquenghem,2108,2048,5)码的闪存纠错算法。然后,对传统BCH编码器进行了改进,提出了一种8bit并行蝶形阵列处理机制。最后,使用地面检测设备对闪存控制器进行了试验验证。结果表明,闪存控制器能快速稳定、可靠地工作,在闪存单页2Kbt/page下可以纠正40bit错误,在相机正常工作行频为2.5kHz下拍摄图像时4级流水线闪存连续写入速度达到133Mbit/s,可以满足空间相机图像存储系统的应用。  相似文献   

5.
基于QC-LDPC码的空间CCD图像NAND闪存存储纠错   总被引:3,自引:3,他引:0  
李进  邢飞  尤政 《光电子.激光》2014,(8):1598-1605
为了提高空间CCD相机图像NAND闪存存储可靠性,提出一种基于QC-LDPC码的NAND闪存纠错算法。首先,分析了NAND闪存纠错信道模型;然后,根据闪存特点提出了一种基于QC-LPDC(1056,1024)码的NAND闪存纠错算法,为了加快编码效率提出了校验矩阵构造和高效编码方法,设计的校验阵均是0和1,只有移位和加法运算,非常适合硬件实现;最后,使用地面检测设备对闪存纠错算法进行了试验验证。结果表明,闪存纠错算法能快速稳定、可靠地工作,计算复杂度比较低,算法复杂度仅具为O(N);算法纠错能力高,误码比(BER)为10-6时,本文算法比RS码多0.47dB编码增益;使用65nm CMOS单元库,系统工作频率为250MHz时解码器数据吞吐率达到7.2Gbps;低误码平层,在误比特率为10-8时未出现误码平层。本文的NAND闪存纠错算法满足了空间相机图像存储系统的应用。  相似文献   

6.
为了满足印刷等高端工业检测中物体快速运动,需要大幅面、高行频、高分辨率图像采集等要求,研发了一款微米级高分辨率、高速线阵工业相机。首先,介绍了高行频、高分辨率国产CMOS图像传感器GL0816的功能与特点。然后,基于该芯片设计了一套高速大幅面高分辨率线阵工业相机系统,该系统采用FPGA作为整个系统的控制核心,以DDR3LSDRAM作为图像缓存器,以GigE vision2.0协议为输出标准,以SFP+作为高速图像输出接口。最后,搭建相机系统测试环境,对所设计的相机进行系统测试。结果表明:该相机系统行分辨率为8 192,可连续采集2 000行作为一帧图像输出,行频为50kHz,动态范围为57.32dB,信噪比为40.95dB,具有实时图像采集功能。该相机系统具有大幅面、高帧频、高分辨率、高信噪比、宽动态范围等优点,适用于印刷检测行业快速运动目标捕获成像及图像实时显示。  相似文献   

7.
航空摄影测量用高清晰视频编码显示系统设计   总被引:2,自引:0,他引:2  
提出了一种帧频可变的高清晰视频编码显示系统.该系统主要由相机控制单元、数据实时处理单元和视频编码单元三部分组成.通过MCU和FPGA的配合,实现了CCD相机的实时帧频处理控制.同时在FPGA内构造数据实时处理单元完成对数据的合成;采用局部选择技术和乒乓缓存技术,为变速的CCD图像原始数据和恒速的视频编码之间构造一个匹配通道并将其打包,最后经由视频编码实现高清晰视频编码显示.目前该系统已通过验证,成功地应用于某无人机的高空拍摄.  相似文献   

8.
为了解决星上图像整合电路工作频率过高而造成的成像系统工作不稳定的问题,在相机的结构上进行创新,提出了一种基于FPGA平台实现的星上TDICCD遥感图像实时合成压缩方法。首先,介绍了星上多通道遥感图像实时合成压缩的原理;然后,针对TDICCD线阵推扫成像模式的特点,采用基于行的2D-DWT整型提升算法,提出了比特平面和编码过程全并行的EBCOT结构,实现了在对图像数据进行整合的同时进行图像的近无损压缩;最后,搭建试验平台进行验证,结果表明,在无损压缩和2倍压缩时,系统主时钟从原来的100 MHz分别降低为80 MHz和64 MHz,系统稳定,恢复图像的PSNR可以达到84 dB,满足大于80 dB的成像质量要求。处理每行的平均时间61.2 s小于相机的最小行周期63 s。算法稳定可靠,实时性好,实现了相机内部的合成压缩,满足实际工程需求。  相似文献   

9.
移动便携图像存储系统的设计   总被引:5,自引:4,他引:1  
为满足Camera Link相机图像存储系统小型化、可移动、易携带的要求,设计了基于Xilinx公司V4系列现场可编程门阵列(FPGA)和TI公司6000系列数字信号处理器(DSP)相结合的硬件电路方案。首先,在FPGA的控制下图像数据缓存到一片SDRAM中,同时读出另外一片SDRAM中缓存的图像,经乒乓操作存储到两块固态硬盘中。其次,DSP与上位机用百兆网连接,在上位机的控制下,DSP从外部存储器接口(EMIF)中获取图像数据后,发送给上位机完成实时显示或者存储图像回放的功能。实验表明:在相机分辨率为640×480、帧频为100f/s且像素为10位时,该系统可以不丢帧地完成图像存储任务。在不需要实时显示的应用场合,系统可以单独完成脱机存储任务,满足Base型Camera Link相机的便携存储要求。  相似文献   

10.
针对目前JPEG2000中最优截断嵌入式块编码器硬件实现效率低且占用大量资源问题,本文提出一种适于空间TDICCD相机图像压缩的JPEG2000比特平面编码器(BPC)。本文提出的BPC结构思想是基于数据路径详细分析来获得上下文窗口的。另外,使用自主研发的地面检测设备对采用本文提出的BPC结构设计的JPEG2000图像压缩系统进行实验。实验结果表明,使用本文提出的BPC结构CCD图像压缩系统可以稳定可靠地工作,BPC具有较高的工作性能,工作频率达到75MHz。压缩系统与传统方法相比较,平均PSNR提高了0.91dB。非常适于空间TDICCD相机的应用。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.  相似文献   

17.
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.  相似文献   

18.
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.  相似文献   

19.
本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。  相似文献   

20.
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.  相似文献   

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