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基于DDS的正弦信号发生器设计 总被引:3,自引:0,他引:3
本设计采用AT89S52单片机,辅以必要的模拟电路,实现了一个基于直接数字频率合成技术(DDS)的正弦信号发生器.设计中采用DDS芯片AD9850产生频率1KHZ~10MHZ范围内正弦波,采用功放AD811控制输出电压幅度,由单片机AT89S52控制调节步进频率1HZ.在此基础上,用模拟乘法器MC1496实现了正弦调制信号频率为1KHZ的模拟幅度调制信号;用FPGA芯片EPⅡ1K30产生二进制NRZ码,与AD9850结合实现相移键控PSK、幅移键控ASK、频移键控FSK. 相似文献
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本文介绍了由FPGA、电源电路、电容/电压转换电路、高精度A/D转换电路等模块组成的电容数据采集系统。该系统以FPGA器件EP3C25为核心,基于DDS算法和D/A转换芯片DAC8830产生载波信号用于电容变化信号的调制,选用24位高精度A/D转换芯片进行电容调制信号的数据采集。详细阐述了系统的硬件设计方案和在Quartus II中利用Verilog HDL语言实现DDS算法和AD7767 A/D采样控制的软件设计方法。实际运行结果表明,该系统能对电容变化进行数据采集,具有精度高及抗干扰性强等优点。 相似文献
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电阻层析成像系统(Electrical Resistance Tomography.简称ERT)具有无扰动.无辐射.可视化.可在线测量等特点。在两相流测量中有很广阔的应用前景。ERT数据采集系统信号发生器模块通常有模拟式和直接数字频率合成(Direct Digital Frequency synthesizer.简称DDS)式两种类型。其中,DDS具有较高的频率分辨率.可实现快速的频率切换。且在频率改变时能够保持相位的连续,很容易实现频率.相位和幅度的数控调制。本文用DDS芯片AD7008及外围电路组成了ERT数据采集系统信号发生模块,产生频率,幅值,相位可调的正弦波。 相似文献
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《仪表技术与传感器》2017,(11)
针对信号隔离与叠加的需求,基于DDS技术,设计了三路相互隔离的正弦波发生电路。设计采用单片机与DDS芯片相结合的方法产生正弦波,通过光纤传送上位机发出的指令至三路单片机,分别控制DDS芯片产生正弦波的幅值、频率及相位参数,单片机接收到指令后控制DDS芯片产生所需的正弦波信号。实验结果表明:该系统正弦波信号的幅值稳定度优于2×10-4,具有实时可调、体积小的优点。 相似文献
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针对传统采用单片机和DDS芯片设计信号发生器的方法具有可移植性差、硬件结构和编写DDS源程序复杂等问题,提出了基于FPGA的多功能信号发生器设计方法。采用MATLAB/Simulink和DSP Builder对DDS系统模型进行建模和仿真,并用Signal Compiler工具对模型进行编译,产生Quartus II能够识别的VHDL源程序,并在Quartus II环境中生成硬件符号,最终将顶层文件编译、综合后下载到FPGA器件中,可产生频率、幅度相位均可调的基本波、AM调制波和数字调制波。测试结果表明,该系统具有设计灵活、实现简单、参数易调整、可移植性好、输出波形性能稳定和精度高等优点。 相似文献
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基于DDS技术与DSP Builder的2FSK设计与实现 总被引:2,自引:0,他引:2
DDS(直接数字合成)是一种新型的频率合成技术,很容易实现频率、相位和幅度的数控调制;2FSK(二进制移频键控)是利用二进制数字基带信号控制载波进行频谱变换的技术。介绍了DDS、2FSK的基本原理,还详细介绍了基于DDS技术、应用Altera公司推出的DSP Builder和QuartusⅡ软件用FPGA实现2FSK的方法。 相似文献
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M. L. H. Low K. S. Lee 《The International Journal of Advanced Manufacturing Technology》2003,21(10-11):807-819
Today, the time-to-market for plastic products is becoming shorter, thus the lead time available for making the injection mould is decreasing. There is potential for timesaving in the mould design stage because a design process that is repeatable for every mould design can be standardised. This paper presents a methodology for designing the cavity layout for plastic injection moulds by controlling the geometrical parameters using a standardisation template. The standardisation template for the cavity layout design consists of the configurationsfor the possible layouts. Each configuration of the layout design has its own layout design table of all the geometrical parameters. This standardisation template is pre-defined at the layout design level of the mould assembly design. This ensures that the required configuration can be loaded into the mould assembly design very quickly, without the need to redesign the layout. This makes it useful in technical discussions between the product designers and mould designers prior to the manufacture of the mould. Changes can be made to the 3D cavity layout design immediately during the discussions, thus saving time and avoiding miscommunication. This standardisation template for the cavity layout design can be customised easily for each mould making company to their own standards. 相似文献
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基于FPGA的嵌入式处理器SOC的设计 总被引:1,自引:0,他引:1
提出一种嵌入式SOC处理器的软核的设计,给出FPGA—CPU的整体结构设计及其细化,逻辑设计的具体实现(VHDL语言程序的编写),软件模拟,以及硬件调试的过程,并给出性能测试结果。该过程对同类设计具有启发和借鉴作用。 相似文献
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Development of Expert System for Concurrent Product Design and Planning for Assembly 总被引:5,自引:3,他引:2
X. F. Zha S. Y. E. Lim S. C. Fok 《The International Journal of Advanced Manufacturing Technology》1999,15(3):153-162
This paper addresses the development of an expert system for concurrent product design and assembly planning (CDAPFAES) including
conceptual design, detailed design, assemblability analysis and design for assembly, assembly system design, assembly process
planning and stimulation, and technical–economics justification. This approach is implemented through an agent-based framework
with concurrent integration of multiple cooperative knowledge sources and software. This intelligent system can offer systematic
assistance for assembly design and planning in the early stage of product development and facilitate, as far as possible,
the use of flexible assembly equipment, including robots. Finally, this new design methodology is illustrated with a successful
implementation of a switch product design. 相似文献
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A new algorithm for reduction of number of press-forming stages in forging processes using numerical optimization and FE simulation 总被引:2,自引:0,他引:2
Ryutaro Hino Akihiko Sasaki Fusahito Yoshida Vassili V. Toropov 《International Journal of Mechanical Sciences》2008,50(5):974-983
This study presents a new simulation-based technique for the optimum design of a multi-stage forging process aiming at reduction of the number of press-forming stages. This iterative design technique involves response-surface-based numerical optimization and a finite element analysis of the process. The design procedure starts with an initial process design that is deemed too conservative, i.e. allows to arrive at the desired product but involves an excessive number of stages. To obtain a better process design, one stage of the existing multi-stage process is eliminated using numerical optimization in conjunction with an FE simulation. This is repeated by reducing the number of stages one by one until the minimum possible number of stages is reached. This design technique is applied to stage reduction of a three-stage forging process of an axisymmetric aluminum billet. It is confirmed that a new two-stage process design is obtained successfully and the developed design optimization technique showed its effectiveness in reduction of the number of press-forming stages in a multi-stage forming process. 相似文献
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介绍了斗轮式堆取料机斗轮装置的设计过程,通过使用三维设计软件Pro/E建立了斗轮装置的实体模型并进行运动仿真,直观地反映了所设计的斗轮装置的运动情况,避免了干涉现象,为提高产品质量,缩短设计周期,进行产品系列化设计打下了基础。 相似文献
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系统地分析了车床主传动系统方案决策的优化设计方法 ,并从图论理论出发 ,运用分级模块式设计方法 ,提出了一种优化车床主传动系统设计方案的新方法 ,建立了数学模型和优化方法 ,该方法和程序可用于车床变速箱传动方案的优化设计 ,可提高设计精度 ,缩短设计时间 相似文献