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《仪器仪表学报》2018,(12)
针对现有正弦压力信号源需要外加机械激励振动源,输出压力信号频率高,机械控制难度大等问题,设计出一种基于磁性液体的低频正弦微压力信号源。通过对螺线管线圈施加正弦激励电流对磁性液体施加磁场力,使之产生交变的磁浮力对外输出正弦微压力信号。研究对螺线管线圈参数进行优化得到较均匀的梯度磁场,计算了一定范围内输出正弦微压力信号与输入电流幅值及频率间的关系并对其影响因素进行简要分析。用有限元仿真方法得到模型内磁性液体中磁场分布及其所受磁场力分布并搭建实验平台进行测试。实验表明,该压力信号源在电源激励频率为0~2 Hz范围内输出的压力信号波形相对最稳定,调节输入电流的幅值与频率控制信号源输出低频正弦微压力信号。 相似文献
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介绍了直接数字频率合成(DDS)技术和压控增益放大器,阐述了一种幅值稳定数控可调的正弦波信号发生器的基本原理.利用ADI公司设计的高性能DDS芯片AD9859以及压控增益放大器AD8336,结合峰值检测电路和STM32微控制器芯片实现宽带幅值稳定数控可调的信号发生器设计.设计能够产生频率准确、幅值稳定的正弦波信号,正弦波频率范围10 kHz~10 MHz连续可调,幅值0~5VPP数控可调,是一种性能良好且简易的数字信号发生器设计,可作为实验室常用的正弦波信号源方案设计. 相似文献
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基于DDS芯片的信号源设计 总被引:4,自引:0,他引:4
文中介绍一种基于DDS芯片AD9833的信号源,该系统采用FPGA与AD9833相结合的方法,以FPGA为控制核心,以AD9833为直接数字频率合成器,以AD8320为幅度调节器,实现了输出频率、幅值和相位灵活可调的正弦波、三角波和方波信号,实测结果表明该系统输出信号频率误差小、分辨率高. 相似文献
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函数信号发生器可以产生方波、三角波和正弦波信号。文中以AT89S51单片机为电路控制模块,通过D/A转换器的输出电压控制压控函数发生器ICL8038的信号产生电路,来产生矩形波、三角波和正弦波,这种电路的频率稳定度高,频率可调范围宽,输出信号的电压幅度较大并且在一定范围内实现连续可调,使用简单,调整方便,性能稳定。介绍了基于AT89S51函数信号发生器电路的整体设计、各单元电路的设计、软件设计及整机测试。 相似文献
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该信号发生器基于直接数字频率合成(DDS)技术,能够输出多种信号(正弦波、三角波、矩形波).在由集成DDS芯片产生的信号基础上,通过自行设计高分辨率程控放大器,实现了对频率、相位及幅值等参数的程控.占空比调节电路设计新颖,其可调范围宽、精度高.整个系统操作方便、实用、性价比高. 相似文献
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为满足互感器现场检定系统的需要,设计并实现了一种程控变频功率源,该功率源以FPGA芯片为核心,采用直接频率合成技术(DDS)产生频率可调的正弦波信号,其输出频率范围为1~200 Hz,精度优于0.05 Hz;功率放大电路部分采用甲乙类双电源互补对称功率放大电路,实现较大的输出容量和高的线性度。 相似文献
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Similar source method (SSM) has been developed to describe interior and exterior sound field by Too et al. [G.-P.J. Too, TK Su, Estimation of scattered sound field via nearfield measurement by source methods, Appl. Acoust. 58 (1999) 261–281]. The application can be used for arbitrary boundary conditions in terms of acoustic impedance. In the present study, a modified version of SSM is developed to describe the sound pressure distribution in a planar surface. In addition, a signal processing procedure is developed to identify noise source locations. This procedure contains a power spectrum analysis and acoustic holographic analysis to identify different source locations. Several test examples are shown to verify this approach. 相似文献
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Total ion current, ion energy, mass and current density distributions, and the impurity content of the ion beams produced by a modified Berkeley multifilament ion source (MFIS) were measured as a function of source configuration, gas pressure, and operating conditions: the 'best' configuration produced beams of 200 mA or more at pressures between 0.40 and 2.0 Pa. In comparison with earlier studies of duoplasmatron and duopigatron sources, the MFIS beams contained less D(+), only ca. 33%, but the beams had much narrower energy distributions and flatter current density distributions. The beams contained 1%-2% impurities which consisted mainly of masses 18, 20, and 22. 相似文献
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The electron beam ion source (EBIS) preinjector at Brookhaven National Laboratory (BNL) is a new heavy ion-preinjector for relativistic heavy ion collider (RHIC) and NASA Space Radiation Laboratory (NSRL). Laser ion source (LIS) is a primary ion source provider for the BNL-EBIS. LIS with solenoid at the plasma drift section can realize the low peak current (~100 μA) with high charge (~10 nC) which is the BNL-EBIS requirement. The gap between two solenoids does not cause serious plasma current decay, which helps us to make up the BNL-EBIS beamline. 相似文献
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O. P. Zakharov 《Instruments and Experimental Techniques》2010,53(6):866-872
A bremsstrahlung X-ray source based on deceleration of electrons in the target is described. Its overall dimensions and cost
are typical of bremsstrahlung sources, and the main parameters of its X-ray beam are similar to those of synchrotron sources.
In a range of Δλ/λ = 10−3, the spectral radiant power of CuKα is at least 100 mW/mrad with a divergence angle of 1 mrad. The direction of the X-ray beam at the outlet is arbitrary, depending
on the source head holder design. The source can be embedded into existing nanolithography systems and used in medical and
industrial introscopes and tomographs, in scientific instruments, etc. 相似文献
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An ion source made from a continuous dynode electron multiplier of the straight channel type and an ion reflector device is described. Its principle of operation is based on a continuous self-sustained ion and electron cascade in the multiplier channel. Operating characteristics and the analysis of the ions produced are presented. The intensity of the total ion current delivered (10(-9) to 10(-8) A) is enhanced by at least six orders of magnitude relatively to previously described similar devices. This source, as illustrated, may be used in gaseous mass spectrometry. 相似文献
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V. T. Cherepin T. A. Krasovsky V. I. Vasilenko A. F. Tverdokhlib 《Instruments and Experimental Techniques》2014,57(2):144-146
A compact multipurpose regulated stabilized high-voltage (from 0 to ± 10 kV) power source for use in industrial and scientific equipment (mass spectrometers, ion optics, photomultiplier tubes, etc.) has been developed. The maximum load current is 400 μA, the noise and ripple in the output voltage are 50 mV or less, and the drift is no more than 2 × 10?4 °C?1. The source is the 95 × 60 × 30 mm module. 相似文献
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