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1.
介绍了基片集成波导技术和ICP深刻蚀微机械通孔阵列的硅基MEMS谐振器,通孔阵列和地平面形成不辐射介质波导,采用CPW电流探针与谐振腔进行信号耦合,在单层硅片上实现了平面电路与三维硅填充谐振腔的信号传输,得到低成本高性能可与平面电路集成的MEMS谐振器.谐振器工作于主模TE101模式,在片测试的Q值大于180,谐振频率21 GHz,与仿真结果吻合,芯片尺寸为4.7 mm×4.6 mm×0.5 mm.  相似文献   

2.
电气刚度是影响MEMS谐振器谐振频率精度的因素之一。但是对于谐振器受到应力时,产生的形变量对电气刚度的影响的理论研究报道甚少。鉴于此,本文对电容式盘结构谐振器受径向静电力和纵向惯性力下的形变量以及电气刚度的改变量进行了系统的理论分析。研究结果表明,当圆盘与电极间隙为50 nm,且电压达到50 V时,圆盘由于静电力产生的径向形变量可达间隙的2.05%,电气刚度改变6.15%。当圆盘半径为100μm,且受到10 000 gn的纵向惯性力时,其最大形变量可以达到圆盘厚度的2.4%,电气刚度改变2.4%。本文分析结果对其他盘结构谐振器的分析亦有重要借鉴意义。  相似文献   

3.
本文设计了一种圆环结构的高Q值MEMS压电谐振器,这种结构的谐振器可在单片RF系统上生产,减少能量损耗,提高Q值,而且不同频率的压电微谐振器的阵列的批量制造在单个芯片上,对其原理进行了分析,仿真,并做出实物进行测试,谐振频率在97.4MHz,Q值达到6499.15。  相似文献   

4.
利用两种新型谐振器设计多层毫米波低温共烧陶瓷(LTCC)滤波器,其一是双环谐振器,另一是分形缺陷梯形谐振器.使用这两种谐振器设计的LTCC滤波器都采用带线结构,整个体积为5.5 inm×2.5mm x0.6mm,利用全波分析软件优化设计并加工出两种结构的滤波器,双环谐振结构滤波器的中心频率为31.5GHz,相对带宽为10.0%,带内插入损耗和回波损耗分别为1.2,11.4dB.分形梯形谐振腔滤波器具有较宽的频带,带宽为30.1-39.20GHz,相对带宽为26.3%.带内插入损耗小于1.9dB,回波损耗小于11.2dB.测试结果与仿真分析数据基本一致,说明方案可行有效,所设计滤波器可以满足毫米波通讯系统的要求.  相似文献   

5.
林丹艳  周希朗 《计算机仿真》2009,26(12):325-328,346
首次提出一种复合左右手传输线零阶谐振器及互补谐振环的新型带通滤波器.设计方法利用左右手复合传输线的独有特性,即零阶谐振器中心频率与谐振器长度无关,能在特定非零频率上得到无限波长的特点,来构造环形滤波器,并且地板蚀刻了长方形互补谐振环结构.设计过程中使用了AnsoftHFSS软件进行全波仿真,经过多次仿真,通过调节参数大小优化设计,最终结果得到中心频率为1.85GHz、带宽为0.1GHz的新型带通滤波器.在达到同样效果的前提下,减小尺寸,单个谐振器与传统相比体积减少了近80%,长方形CSBR还提高了传输特性.上述结构的实现对于左手材料在微波器件中的发展有一定的促进作用,进一步扩大了左手材料的应用范围.  相似文献   

6.
针对认知无线电技术对射频微波滤波器的新要求,提出了一种基于枝节加载多模谐振器的电调微波滤波器。该电调微波滤波器由一个枝节加载微带多模谐振器和变容二极管组成,实现了滤波器的小型化。在分析枝节加载微带多模谐振器的基础上,通过在微带谐振器两端和加载枝节上加载变容二极管的方法,设计了枝节加载的电调多模微带谐振器,并提出了复杂微带谐振器谐振特性的分析方法。采用源和负载耦合的方法在通带右边引入一传输零点。通过在源和负载端放置耦合线的方法,提高了滤波器的通带选择性。针对滤波器带外衰减小的问题,引入一种新型的频变馈电结构,改善了滤波器的带外衰减特性。通过优化仿真确定了电调滤波器的尺寸参数。仿真验证了该滤波器的特性,当变容二极管的可调范围为2pf-10pf时,滤波器的频率可调范围为2.10GHz-2.40GHz,频率变化范围为300MHz。  相似文献   

7.
微谐振器是试飞测试系统的重要组成部件,微谐振器的性能影响到试飞测试系统的精确度.为了提高微谐振器的性能,在传统结构的基础上,提出改变微谐振器中折叠梁、驱动梳齿等结构的尺寸来改善其性能.运用有限元法对不同结构尺寸下的微谐振器进行模态、品质因子分析.仿真结果表明,横向微谐振器的一阶模态频率的大小很大程度上受到折叠梁尺寸的影响;静电梳齿的尺寸设计中,梳齿的宽度是影响驱动力和品质的一个关键因素.仿真结果表明,对提高微谐振器的性能具有一定的指导意义.  相似文献   

8.
设计了一种由超磁致伸缩材料Terfenol-D和SAW谐振器构成的复合磁传感器,在磁场作用下,Terfenol-D沿长度方向伸缩,并将应力应变传递至SAW谐振器,使其产生应变,造成谐振频率改变,通过测量SAW谐振器谐振频率的变化来测量磁场强度.分析了该磁传感器的传感原理,建立了该复合磁传感器的静态模型,对弹性敏感元件进行了受力分析,根据压磁方程和受力平衡得到该磁传感器的静态特性.实验结果表明:该复合磁传感器灵敏度可达341.6Hz/Oe,较Terfenol-D/SAW谐振器结构灵敏度提高了3倍;测量谐振频率的分辨率为1Hz,SAW谐振器频率稳定度为0.1×10-6时,该磁传感器对磁场的分辨率为10-6T.  相似文献   

9.
提出了一种新的谐振式传感器的工作方法,采用线性调频信号激励谐振器,当激励信号断开后,谐振器将以其谐振频率做自由振动,通过测量谐振器自由振动状态下的振动频率,即可测得谐振器的固有频率.文中通过仿真分析,对比了正弦信号激励和线性调频信号激励时,谐振器的储能情况和谐振器响应信号的幅度.仿真结果表明采用线性调频信号激励可以较好地实现谐振式传感器的间歇工作方法.  相似文献   

10.
不等基频硅微谐振式加速度计   总被引:1,自引:0,他引:1  
陈卫卫  黄丽斌  杨波 《传感技术学报》2011,24(11):1538-1541
分析了硅微谐振式加速度计的两个谐振器在谐振频率相交点附近区域产生耦合的原因,设计了一种新型的不等基频硅微谐振式加速度计,并对其进行了有限元仿真.该加速度计由质量块、放大惯性力的杠杆机构以及一对尺寸不同的谐振器组成.采用DDSOG工艺加工.利用ANSYS有限元软件进行仿真,结果表明加速度计上谐振器的谐振基频为124 67...  相似文献   

11.
针对油气井中井眼口径窄小、高温、高冲击等恶劣环境,采用双轴一体光纤陀螺和石英挠性加速度计作为核心传感器部件,实现了轻小型二位置光纤陀螺测斜仪惯性测量单元(IMU)。采用DSC(dsPIC30F6014A)+FPGA双CPU导航计算机方案完成导航计算和滤波算法以及IMU数据的采集、控制与传输等功能。重点介绍了系统工作原理,IMU、数据采集与接口电路和双微处理器设计等硬件结构及软件算法。样机测试结果表明:该样机达到了预期精度指标要求(井斜角精度优于±0.2°,方位角精度优于±2°,工具面精度优于±0.5°),系统的性能尺寸体积、重量等方面达到了井下测斜仪器设计要求。  相似文献   

12.
本文提出一种新型的全视场数字太阳敏感器设计方法,其光学系统由全景鱼眼镜头和滤光膜组成。采用低功耗设计,在满足精度的要求下,使其能够适应微小卫星对于数字太阳敏感器功耗的限制。从工作原理出发,建立起该敏感器模型并通过软硬件实现,利用太阳模拟器对数字太阳敏感器进行标定及误差分析。实验表明,基于全景鱼眼镜头的数字太阳敏感器的视场为180°×360°,在160°×360°视场的测量3δ精度优于0.18°,整机功耗150 mW,能够满足微小卫星姿态确定系统对于数字太阳敏感器的需求。  相似文献   

13.
In this paper, a broadband dielectric resonator antenna (DRA) with a simple H‐slot feeding structure is proposed. The broad bandwidth (~45%) and uni‐directional radiation enable this DRA suitable to work as a radiation element in the construction of a beam‐scanning array with not only low frequency sensitivity which is important for accurate angle estimation of in‐coming targets, but also a wide scanning range. Moreover, stable coupling coefficients are established around all the above three resonances with respect to its corresponding feeding line, ensuring a low sidelobe level (SLL) across the whole operating frequency range. In order to realize such a DRA, a latticed rectangular structure is utilized to generate the lower two resonances, while the upper resonance is generated by its H‐shaped feeding slot. The shape of the latticed dielectric resonator is also modified according to a 3‐D printed fixing structure for an accurate installation. A 20‐element beam‐scanning prototype is demonstrated and manufactured. The range of scanning angle is from ?36° to +13° within the bandwidth of 10 to 16 GHz, corresponding to a frequency sensitivity of only 122.5 MHz/o. The achieved SLL are smaller than 19 dB for all scanning beams. The above performance indicates that, this array is very suitable for near‐range radar systems requiring an accurate angle estimation.  相似文献   

14.
We propose a method to suppress deceptive jamming by frequency diverse array (FDA) in radar electronic countermeasure environments. FDA offers a new range-angle-dependent beam pattern through a small frequency increment across elements. Due to the coupling between the angle and range, a mismatch between the test angle and physical angle occurs when the slant range on which the beam focuses is not equal to the slant range of the real target. In addition, the range of the target can be extracted by sum-difference beam except for time-delay testing, because the beam provides a range resolution in the FDA that cannot be deceived by traditional deceptive jamming. A strategy of using FDA to transmit two pulses with zero and nonzero frequency increments, respectively, is proposed to ensure that the angle of a target can be obtained by FDA. Moreover, the localization performance is examined by analyzing the Cramer-Rao lower bound and detection probability. Effectiveness of the proposed method is confirmed by simulation results.  相似文献   

15.
延迟求和波束形成(DSB)在麦克风阵列信号到达角估计上有着广泛应用,然而在语音信号源下由于栅瓣等问题使得该方法对多个语音信号源方位估计不理想,此外,在实际复杂环境下,该方法受噪声混响影响,方位识别更加困难。针对这些问题,提出一种改进的DSB方法,联合信号频率及麦克风阵列间距对子段内的频点进行选择,之后对数据协方差矩阵加权处理。同时在仿真及实际环境下进行实验,结果表明,与未改进DSB方法相比,该方法计算量降低为原来的18.37%,有效地降低了运算量;仿真实验中在不同反射系数0.2、0.4、0.6下,平均角度定位偏差分别降低了27.3%、21.4%、36%;实际环境实验方位角度估计偏差最大值为9°、最低为1.35°,要低于未改进算法的12.1°和3°。  相似文献   

16.
在介绍人脸特征点检测的理论知识的基础上,提出了一种基于深层卷积神经网络(Deep Convolutional Neural Network,DCNN)解决人脸5点特征点(眼角、鼻子、嘴角)预测问题的方法。通过添加更多的卷积层稳定地增加网络的深度,并且在所有层中使用3×3的卷积滤波器,有效减小参数,更好地解决了人脸特征点检测问题。然后计算双眼角与嘴角所成平面与正视时此平面的单应性矩阵,最后利用等效算法求解驾驶员面部转角。实验结果表明,面部特征点检测准确率达到97.96%,算法在角度判断上的误差是1°~5°,这证明了该算法对注意力分散监测的有效性。  相似文献   

17.
不同入射角下的雷达后向散射系数图像模拟   总被引:1,自引:0,他引:1  
选择了新疆渭库三角洲(库车县、新和县、沙雅县)为实验区,利用Ulaby和Chapp的后向散射模型分别模拟了HV极化和HH极化的入射角为20°、24°、30°、33°、37°和40°的雷达后向散射系数图像。分析了不同入射角下图像各点后向散射系数值的散点图以及统计特征,得出由于入射角度的变化,两种极化的图像后向散射系数值变化较大,其变化趋势均符合余弦函数曲线分布,且模拟SAR图像很好的保留了地面散射信息。  相似文献   

18.
针对常规频控阵(FDA)采用线性频偏增量产生的“S”形波束图在角度和距离上耦合和分辨率不够高的问题,提出一种新型频控阵——基于正弦频偏的多载波FDA。设计并建立了布阵模型,分析了信号模型,推导了在远场形成的发射波束方向图。通过MATLAB对该频控阵的仿真,结果显示该频控阵能够在目标位置处形成点状波束,在发射能量聚焦性能和阵列分辨率性能上均优于现有的对数频控阵。  相似文献   

19.
In this article, a filtering antenna array based on substrate integrated waveguide (SIW) is proposed with quasi‐elliptic gain responses for the first time. Two radiation nulls in the gain responses at two sides of the frequency band edges are designed by applying a novel intercavity bypass coupling scheme. First, by carefully analyzing the bypass coupling between the in‐band and out‐of‐band modes in a single oversized TE103 mode cavity resonator, quasi‐elliptic filtering responses are achieved for a two‐output filter. Afterward, those cavity resonators coupled with the two outputs are replaced by cavity‐backed slot antennas to achieve the proposed filtering cavity‐backed slot antenna array. Only one cavity is required in our design to achieve the two transmission zeros and the function of power divider. As a result, the complexity of the proposed filtering antenna array is reduced. A prototype operating at Ka band is designed, fabricated and measured with a center frequency of 28.5 GHz and fractional bandwidth of 1.25%. Similar characteristics can be observed between the gain response of the proposed filtering antenna and the transmission responses of the two‐output filter. The proposed SIW filtering antenna array has great potential to be integrated into millimeter‐wave transceiver modules. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:191–198, 2016.  相似文献   

20.
Lin D  Nussbaum MA 《Applied ergonomics》2012,43(6):1008-1015
A number of work environments require workers to perform tasks on inclined surfaces. Such tasks, along with muscle fatigue, can impair postural control and increase falling risks. The objective of this study was to determine the effects of surface inclination angle, standing direction, and lumbar extensor fatigue on postural control during quiet standing. A group of 16 young, healthy participants were tested while standing on inclined surfaces before and after lumbar extensor fatigue (induced by repetitive isotonic exercise). Three inclination angles (0°, 18° and 26°) and three standing directions (uphill, downhill, and lateral facing) were examined. Postural control was assessed using several measures derived from center-of-pressure time series and subjectively perceived stability. Significant main and interactive effects of inclination angle and standing direction were found for all dependent measures. The adverse effects of standing on inclined surfaces were found to differ between the three standing directions. In general, dose-response relationships with inclination angle were evident, particularly in the lateral-facing direction. Fatigue-related effects differed between conditions, suggesting that the adverse effect of lumbar extensor fatigue on postural control depend on inclination angle and standing direction. These findings may facilitate the development of fall prevention interventions for work involving inclined surfaces.  相似文献   

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