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基于单片机与FPGA的等精度频率计设计 总被引:1,自引:0,他引:1
根据等精度测频原理,利用单片机与FPGA结合设计等精度数字频率计。待测频率信号经过整形放大后输入到FPGA,单片机控制FPGA通过内部脉冲计数器对待测信号和标准信号源同时计数,单片机读回测频数据后,经运算处理后显示。等精度频率计测频精度高,且精度不随频率的变化而变化。单片机与FPGA结合,测频速度快,范围宽,可靠性高。 相似文献
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针对便携式、小型化与低功耗的需求,采用可编程逻辑器件FPGA 作为主控制器,设计一款便携式双通
道信号源。采用CORDIC 算法实现DDS 正弦信号的产生,输出2 路幅频相连续可调的正弦信号;利用智能触控屏
设计信号源的人机交互接口,对信号源参数进行配置与实时显示;触控屏与FPGA 之间采用Modbus RTU 协议进行
通信。实际测试结果表明:该信号源输出的正弦信号频率稳定性好,相位、幅值调节准确性好,能够满足测试设备
的需求。 相似文献
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针对实验室无线电引信测试系统回波信号延时精度低的问题,基于FPGA平台,提出通过数据存储和数据选择方式来实现引信测试系统回波信号高精度延时。该方法利用自行编写的算法控制粗延时单元中的数据存储和精延时单元中的数据选择方式进行实现,在满足延时要求的基础上,有效提高了引信测试系统回波信号的延时精度。实验结果表明,本文提出的粗延时单元设计方案能够满足引信测试系统回波信号的延时需求,精延时单元设计方案能够将延时精度从FPGA时钟周期的4ns提升到1ns,意味着引信定距测试精度从0.6m提升到0.15m,测试精度提升到了一个更高的水平。 相似文献
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为满足以太网、CAN 总线和多路串口通信的需求,设计一种基于DSP+FPGA 的多路串口和以太网通信
系统。介绍基于DSP+FPGA 多路串口及以太网通信系统组成和工作原理,分别对DSP 电路、FPGA 电路、电源电路
的组成结构进行说明,对系统软件的功能进行阐述。应用结果表明:该通信系统具有运行稳定、性能可靠等优点,
可满足项目研制的需求。 相似文献
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武器装填控制测试系统由PLC主控机,数据实时采集与逻辑分析,多路信号转换与功能判断等模块组成.系统软件包括主程序、子程序、显示程序.PLC切换巡回检测点,分析采集信号、建立故障模式.通过多路信号转换、开关量识别,模拟量实际值与系统允许极限值比较,及输入、间隔定时器和高速计数器等中断处理,实现故障诊断. 相似文献
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Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily. 相似文献
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The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS (geographical information system) data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms. 相似文献
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Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design. 相似文献
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By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux (kernel version 2.6.11 ) is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development. 相似文献
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For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further. 相似文献
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阐述了数码电子雷管中,点火药剂细结晶三硝基间苯二酚铅(LTNR)的制备工艺;从点火药剂的种类、加入黏合剂的质量分数、桥丝直径、点火头的电阻值、防潮漆的蘸涂等方面对点火头性能的影响因素进行了探讨;通过震动试验、并联起爆试验、延期精度检测与考核,试验结果表明:一次性合成的细结晶LTNR是制造数码电子雷管点火头较为理想的点火药剂,按技术要求生产的点火头性能指标能够满足行业标准要求。 相似文献
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By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly. 相似文献
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The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite. 相似文献
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Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective. 相似文献
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A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same. 相似文献