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基于喇曼-奈斯衍射的微光机电加速度计理论分析和原理验证 总被引:1,自引:1,他引:0
本文设计并模拟了了一种新型的基于喇曼-奈斯衍射的微光机电(MOEMS)加速度计。该加速度计将通过MEMS技术制造,并具有与已见报导的MOEMS加速度计完全不同的敏感原理。本文详细讨论了该新型加速度计的基础理论与原理;建立了弯曲板波延迟线振荡器的3D有限元模型,进行了谐响应分析和瞬态分析,得到器件工作频率在40MHz左右;最后建立了该微型加速度计的宏模型,对该器件的可行性进行了论证。该新型加速度计具有灵敏度高、抗辐射等优点,具有很大的应用前景。 相似文献
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证明了SAW延迟线振荡器的谐振频率对淀积在延迟线表面上的有机薄膜很敏感。理论指出SAW器件对质量负载的灵敏度取决于谐振频率的平方。用谐振频率为31,51和112MHz涂有严格控制成分及厚度的有机膜的器件对这个关系进行了实验研究。若器件用上合适的吸附性涂层,可将SAW振荡器的质量灵敏度用于制造非常灵敏的化学传感器。从工作频率为290MHz的SAW延迟线振荡器(是迄今所报道过的最高频率的SAW化学传感器)得到的结果表明,要对浓度大体低于1×10~(-4)(以体积计)的有机气体进行快速探测是容易办到的。 相似文献
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近几年来,高稳定性SAW振荡器的研制已取得了重大的进展,能对密封的SAW谐振器精确地进行频率调整,SAW振荡器的频率稳定性也有了显著的改进。500MHz SAW谐振振荡器的相位噪声达到了-184dBc/Hz,同时在10Hz的载波偏置条件下,闪变效应噪声为-83dBc/Hz。在±150kHz调谐范围内,验证了400MHz SAW延迟线振荡器样机的相位噪声为-170dBc/Hz,在10Hz的偏置条件下,其闪变效应噪声电平为-70dBc/Hz。检测到SAW器件的振动灵敏度为10~(-10)/g量级,最近还对采用混合电路的900MHz SAW谐振振荡器进行了同样的振荡灵敏性检测。按规定制作的500MHz SAW谐振振荡器的长期频率稳定性高达±1ppm/a。 相似文献
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针对轴对称壳形振动陀螺的工作机理与振动特性,提出了一种新颖的全对称U型梁MEMS环形波动陀螺,并分析了其工作原理、振动特性与敏感工作方式。在此基础上应用ANSYS有限元分析软件建立了该环形振动陀螺谐振结构的有限元模型,分别进行了模态分析、谐响应分析、瞬态冲击响应分析与静力分析。仿真分析结果显示该环形陀螺驱动与敏感模态固有频率的频差为33 Hz,工作模态的频率匹配性较好;工作模态与其他振动模态的最小频差为1 032 Hz,能够有效抵抗环境振动的干扰;谐振结构在10 000g的瞬态冲击作用下最大应力为39.5 MPa,可以正常稳定工作。 相似文献
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本文使用两块平行极板及其测量、控制和显示电路,实现纸张计数和显示功能。具体方案采用555多谐振荡器电路将纸张数目变化引起的两极板间电容的变化,转化为谐振回路的振荡频率变化。通过大量实验校准拟合纸张数目和谐振回路频率的对应关系。进而通过STC12C5A60单片机构建的频率测量模块完成测频,计算校正后驱动LCD显示纸张数目或极板是否处于短路状态。 相似文献
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氮化铝轮廓模式谐振器(CMR)能够满足现代无线通信对单片、多频段、可重构的多频率源的需求,具有很大的应用前景。针对目前无具体单个CMR频点的设计方法,提出了一种结合CMR性能参数的影响因素分析和有限元计算的CMR设计方法。该文对CMR的谐振频率、质量因子、机电耦合系数和动态电阻等谐振器主要性能参数的影响因素进行理论分析得到CMR结构的初始尺寸,再利用COMSOL有限元软件建立CMR几何模型并进行频域求解得到相应的频率-导纳曲线和频率-质量因子曲线;根据仿真结果和理论计算对CMR初始结构尺寸进行优化,并仿真设计了一个氮化铝CMR,其谐振频率为300 MHz,质量因子约为1 010,机电耦合系数约为1.64%。 相似文献
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A theoretical derivation of theQ-factor of an MSW delay-line based oscillator is presented which is based on a rigorous, classical definition of theQ-factor of a resonator. The theory takes into account (1) the propagation loss in the delay line, (2) the transduction losses at the input and output transducers of the delay line, (3) the delay times in the delay line and the circuit external to the delay line, and (4) the loading of the oscillator. While the present work was done with MSW in mind, the results are generally applicable to all delay-line based oscillators and would, for instance, apply to the SAW delay-line based oscillators. 相似文献
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《Microwave Theory and Techniques》1984,32(2):171-176
The design, construction, and experimental test results of a mechanically tunable Gunn oscillator using a recessed diode metal coaxial cavity coupled to an image line waveguide is described. The oscillator frequency was changed by about 10-percent by varying the bias post length into the coaxial structure. The oscillator is designed so that both the Gunn diode and resonant cavity can be quickly replaced to provide extended frequency coverage and efficiency. This Gunn diode oscillator has provided up to 15-mW CW power at 60 GHz with 10-percent tuning range. 相似文献
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《Microwave Theory and Techniques》1962,10(2):108-113
A theoretical derivation is made of bandwidth as a function of resonant frequency of a single crystal ferrite resonance isolator at millimeter wavelengths. The derivation takes into account the ferrite isolator as a bounded system. Using the derived relation of bandwidth and resonant frequency, and Kittel's relation between resonant frequency and applied field, equations are derived which relate line width to resonant frequency, line width to the applied magnetic field, and line width to frequency bandwidth. These resulting equations are compared with experimental data obtained with a single crystal barium ferrite isolator from 58 to 59 kMc. The theoretical relations agreed closely with the experimental data within the accuracy of the measuring equipment at these frequencies. In general, the results showed that for small frequency ranges (1 kMc) bandwidth and line width increase almost linearly with frequency, bandwidth and line width are linearly related, and line width is a fairly complicated but increasing function of applied field. 相似文献
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A 30-GHz Self-Injection-Locked Oscillator Having a Long Optical Delay Line for Phase-Noise Reduction 总被引:1,自引:0,他引:1
《Photonics Technology Letters, IEEE》2007,19(24):1982-1984
We demonstrate a millimeter-wave self-injection-locked (SIL) oscillator having a long optical delay line as a feedback route. In the SIL oscillator, a part of output signal is self-injected into the oscillator after passing through a long optical delay line, resulting in locked oscillation and phase-noise reduction. By controlling the self-injection power, we achieve 30-GHz oscillation with a sidemode suppression ratio larger than 50 dB and about 18-dB phase-noise reduction at 10-kHz frequency offset. 相似文献
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A new technique for achieving frequency modulation with a surface-acoustic-wave delay-line oscillator is reported. A 339MHz s.a.w. delay line has been fabricated on an epitaxial garnet film. A significant phase-velocity shift has been measured as a function of an inplane magnetic field. An s.a.w. oscillator has been implemented with this delay line and its frequency has been controlled by the magnetoelastic effect. A frequency shift of 600kHz (a relative variation of 1.75 × 10-3) has been obtained by changing the biasing magnetic field. 相似文献
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We describe the design of a microwave oscillator using resonant tunneling diodes. The devices are fabricated from Al0.3Ga0.7As-GaAs double barrier hetero-structures grown by molecular beam epitaxy. Design criteria improving current drivability are established from a theoretical study of tunneling transmission probabilities. Very high peak current densities up to 3.104 A/cm2, favorable for high frequency operation as an oscillator, have been achieved experimentally. The devices exhibit stable oscillations at liquid nitrogen temperature and at room temperature when the tunnel diode oscillator is constructed with a stabilizing network. 相似文献
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Seong-Jin Jang Young-Hyun Jun Soo-In Cho 《Electronics letters》2003,39(2):189-190
A virtual fine delay line (VFDL) using only two ring oscillators and counters can cover a wide frequency operation range clock without adding any additional delay line stage. The proposed ring oscillator can easily make a unit delay as a one-stage inverter. The VFDL achieves fine resolution of less than 60 ps and small circuit area with two clock cycles lock-in time. 相似文献