空心顺变柱体型三分量全光纤加速度地震检波器

设计了介绍一种新型空心顺变柱体型三分量全光纤加速度地震检波器。该检波器作为加速度检测设备,采用3个迈克尔逊光纤干涉仪光路,用6个空心顺变柱体共同支撑1个质量块构成三维简谐振子系统。对实验样机进行的模拟实验测试表明:共振频率为308Hz,工作频带向低频移动,频响特性曲线与理论计算相符。加速度灵敏度的理论计算值为15.7×103rad/g,能满足大多数场合下对加速度精确测量的要求。     

基于光纤Bragg光栅的地震检波器的理论与实验研究

提出了一种新型的基于光纤Bragg光栅(FBG)的地震检波器。FBG地震检波器传感头由平面弹簧片、质量块和FBG构成。给出了该检波器的力学模型,理论推导与分析了该检波器的幅频特性和加速度灵敏特性,并讨论了影响该检波器灵敏度的主要因素。实验结果表明,该检波器具有良好的线性度、稳定性和耐受性;检波器的频率响应范围为10～140 Hz,传感器灵敏度为25.9pm/g,共振频率为167 Hz,较符合理论值;最高可检测加速度值大于30g。     

双膜片结构光纤光栅地震检波器低频特性的研究

提出了一种双膜片式的光纤光栅(FBG)地震检波器,此结构有效限制了检波器横向响应。对该检波器的纵向加速度灵敏度和幅频特性进行了理论分析,并指出了影响这种检波器纵向加速度灵敏度的因素。实验结果表明,该种检波器在5～200Hz频率范围内频响平坦,纵向加速度灵敏度为24.3pm/g,谐振峰在900Hz附近,与理论计算较好的吻合。     

光纤干涉式振动传感器中顺变柱体刚度系数的计算方法

从能量分配角度分析了光纤干涉式顺变柱体传感器的工作原理,给出了复合顺变柱体的等效刚度系数计算公式。采用有限元分析方法对复合顺变柱体进行固有频率的仿真,并得出光纤缠绕起始位置应该距离中间惯性振子5mm的结论;实验采用固有频率测量的方法间接计算顺变柱体的等效刚度系数,对三个顺变柱体传感器进行的测量实验结果表明,该方法可作为顺变柱体复合刚度系数计算的依据。     

基于边缘滤波解调的光纤光栅低频地震检波器

研究了悬臂梁结构的光栅振动加速度传感器并提出了一种圆柱体形光纤Bragg光栅地震检波器模型,用边缘滤波的解调方法对此检波器的性能进行了实验研究.研究表明:所提出的光纤Bragg光栅地震检波器的方案是可行的,而且具有很高的检测精度、灵敏度、失真度和长期的稳定性,通过改变圆柱体内的阻尼,可使检波器的带宽和性能得到进一步提高;通过对质量块的调节,固有频率为140 Hz,灵敏度可达到69 pm/g.解调检测波长灵敏度可达-1.27 pm/mV,系统的波长分辨力为1.1 pm.     

一种高效实用的相干自适应雷达检波器

推导出了一种适用于未知参数的AR噪声中有未知多普勒和未知复值振幅情况的雷达目标自适应检波器，辅助数据也可用来改进检测性能，拟议的检波器具有检波器组的形式，还要介绍有效实现该检波器组的计算量，同时使用模拟和实际的杂波数据来估计拟议检波器的性能。     

一种可用于油藏监测的3分量光纤加速度传感器

研制了一种可用于油藏监测的3分量光纤加速度传感器。该传感器通过3个单方向传感单元分别获得3个正交方向上的被测加速度分量,每个传感单元是一质量-弹簧系统,通过波纹管与顺变材料构成复合弹性体,并采用光纤干涉结构将被测加速度通过解调光纤中的相位变化反映出来。实验数据表明,该加速度传感器具有良好的线性度、一致性和稳定性。系统的工作频带范围为10Hz至800Hz,其轴向灵敏度为38dB re rad／g,交叉法去敏度达到32dB re rad／g,最小可检测加速度为39．3μg／Hz^1／2。     

三分量加速度地震检波器中3-dB耦合器设计

三分量加速度地震检波器检测加速度的核心部件是由2个3-dB耦合器级联而成的双M-Z干涉仪,3-dB耦合器的设计对三分量加速度地震检波器的检测精度尤为重要。介绍了三分量加速度地震检波器的结构和工作原理,导模之间的同向耦合理论。设置了3-dB耦合器波导的结构和计算参数。采用MATLAB对3-dB耦合器的输出功率进行仿真,仿...     

新型陆用压电加速度地震检波器问世

由陕西省西安海丰传感技术发展有限责任公司研制成功的陆用压电加速度地震检波器，5月9日顺利通过陕西省科学技术厅组织的科技成果鉴定，它标志着我国传统地震检波器有了自己的升级换代产品。     

迈克尔逊干涉型加速度地震检波器集成芯片

提出了一种新型的迈克尔逊干涉型混合集成光学加速度地震检波器。以尺寸为38mm×6mm×2mm的X切Y传LiNbO3晶体为基底,详细分析并设计了迈克尔逊干涉芯片的双Y分支波导、相位调制器和偏振器。对成功制作的迈克尔逊干涉芯片进行了通光测试,并对检测器进行了测试。结果表明,检波器及芯片性能良好,振动与检波器输出信号吻合良好。该检波器系统的主要设计参数为:自然频率3549Hz,相位检测灵敏度ΔΦ/a为1.1×10-2rad/m/s2,工作频带0～1065Hz。     

微机械双轴电容式加速度传感器设计

设计一款机械噪声较小、灵敏度较高的双轴电容式加速度传感器,其具有4个水平检测单元,X、Y轴向的检测单元各有两组,且水平对称,有效地消除了轴间的交叉干扰;结构中的保护限位装置避免了结构因加速度值过大而断裂失效和结构测量的不准确。该加速度敏感质量块的大小为3 250 μm×3 250 μm×5 μm;栅型条的尺寸大小为1 575 μm×35 μm×5 μm;间距为35 μm,利用Ansys软件对加速度传感器进行性能仿真,得出加速度传感器X和Y轴向的静态灵敏度为0.253 μm/g;电容灵敏度为1.533 pF/g;X和Y轴向的谐振频率为949 Hz,阻尼比为0.83。     

Digital Synthetic-heterodyne Interferometric Demodulation Based on Embedded System

Optical fiber acceleration seismometer as an important instrument can offer high sensitivity, anti-jamming and non-touched advantage which has an extensive application field. Its signal processing ability will decide whole system＇s performance to some extent because it will affect directly the factors such as resolving power, precision and dynamic range. The signal processing is usually realized by analog circuits which was more inferior in stability, flexibility and anti-jamming to digital processing system. A digital processing system of optical fiber acceleration seismometer has been designed based on the embedded system design scheme. Synthetic-heterodyne demodulation has been studied, and signal processing has been realized. The double processors of ARM and DSP are employed to implement respectively the system control and signal processing, and to provide the output interfaces such as LCD, DAC and Ethernet interface. This system can vary with the measured signal in real time and linearly, and its work frequency bandwidth is between 10 Hz and 1 kHz. The system has better anti-jamming ability and can work normally when the SNR is 40 dB.     

金刚石NV色心加速度传感效应研究

提出了一种基于金刚石氮空位（NV）色心磁敏感机理的加速度传感方案。永磁体作为质量块,外界加速度使永磁体与NV色心的距离变化,使得作用在金刚石NV色心上的磁场强度发生改变,通过对NV色心电子自旋共振（ESR）荧光信号的分析实现对加速度的检测。实验在沿永磁体轴线方向距表面10mm范围内对加速度效应进行验证。测试得到基于金刚石NV色心的加速度传感可以实现对±0.02g内的加速度进行检测,检测灵敏度为108.31V/g。     

Cirrus芯片在矿用地震仪中的应用

针对煤矿井下地震仪器的特点,选用Cirrus Logic公司的地震勘探芯片组作为采集系统的核心部件。文中介绍了Cirrus Logic芯片的主要特点、构成、工作原理,并将其应用于矿用地震仪器中,设计了其硬件电路、并编写了控制软件,进行了试验测试。实验结果表明,所设计的仪器达到了煤矿井下防爆、微型化、低功耗、高速、高精度和便携性等要求。     

耐高冲击过载电容式微加速度计设计

针对近年来常规弹药制导化改造对经历高动态环境的加速度传感器的迫切需求,该文设计了一种抗高过载、低量程的微机电系统(MEMS)电容式加速度传感器。该加速度传感器使用4组折叠梁组对可动结构进行支撑,并带动其在敏感方向移动,同时敏感结构采用差分式电容检测结构和叉齿止档限位结构方案,降低了结构受冲击时的区域应力,提高了输出信号增益及传感器灵敏度。理论计算和有限元分析结果表明,传感器轴向灵敏度为0.22 pF/g(g=9.8 m/s²),可承受轴向幅值为3×10⁴g、脉宽约8 ms的加速度冲击。     

An investigation of the pressure-to-acceleration responsivity ratioof fiber-optic mandrel hydrophones

The acceleration responsivity of the fiber-optic air-backed mandrel hydrophone is studied. This responsivity may be a significant noise source in high vibration environments. The pressure-to-acceleration responsivity ratio is therefore a figure of merit for the hydrophone. It is shown that an ideal hydrophone with a sufficiently rigid support cylinder should not show any first-order acceleration responsivity. The dominant contribution to any first-order acceleration responsivity is the deformation of the support cylinder due to acceleration. The responses are evaluated both theoretically and experimentally. This treatment gives a set of guidelines which should be followed in order to maximize the pressure-to-acceleration responsivity ratio. It is also theoretically and experimentally demonstrated that the axial acceleration responsivity can be significantly reduced by symmetrical elicitation of the hydrophone     

基于DSP的地震波信号采集仪设计

设计一种基于数字信号处理器(DSP)的地震波数据采集仪.该仪器以TMS320VC5410A为系统运算处理器,负责针对地震波信号的数学分析.本文简单介绍了VectorSeis数字三分量检波器的优越性,给出了DSP主要外围电路(包括复位电路、电源模块、存储器控制电路)的实现,重点介绍了DSP与PC之间基于USB接口通信的软...     

基于MEMS技术的水平轴光纤加速度传感器

提出了一种基于微机电系统(MEMS)技术的水平轴光纤加速度传感器,并与Z轴光纤加速度传感器在同一MEMS芯片上制造,形成单一方向出纤的三轴光纤加速度传感器。分析了器件工作原理和器件结构参数与其性能的关系,利用MEMS技术成功制作出了加速度传感器样品。初步测试结果表明,本光纤加速度传感器灵敏度为164mV/g,3dB带宽的截止频率为1 600Hz。     

A monolithically integrated three-axis accelerometer using CMOScompatible stress-sensitive differential amplifiers

In this paper, the development of a bulk-micromachined CMOS integrated three-axis accelerometer which includes analog signal conditioning circuits is presented. The accelerometer was designed to simplify the signal processing tasks by incorporating a set of circuits for three-axis signal conditioning. This approach resulted in a 25% reduction of the circuit area. Stress-sensitive differential amplifiers (SSDAs) have been used as signal transducers, because they can be conveniently formed in a small area. The sensitivity and resolution of the fabricated devices realized in 8×8 mm² die area were 192 mV/g and 0.024 g for Z-axis acceleration, and 23 mV/g and 0.23 g for X and Y axis acceleration, respectively. The electrical noise component in the analog CMOS circuits was reduced by using a chopper stabilization technique. It was observed that there is a proper chopping clock frequency range to maximize the noise reduction effect. The noise of the SSDA was found to be related with the characteristics of CMOS differential amplifiers used. Typical temperature coefficient of sensitivity was about -2000 ppm/°C, which could be reduced to -320 ppm/°C or less by selecting a proper bias condition     

A cost-effective three axis CMOS accelerometer combining micromachining and digital technology

In this paper, a three axis accelerometer is successfully developed by a mixing-mode chip design using CMOS surface-micromachining technology. The chip consists of mass-spring, the analog core and the digital circuit. The vibration sensor is implemented with micro-spring to change the capacitance between two metals. The analog core detects the capacitance differential to the frequency shifting using an oscillator. The digital control is to compute the amount of acceleration to the form of digital bit. The chip can detect the acceleration to 140 g for x axis and y axis with 10-bit resolution, and from 110 g for z axis with 9 bits. The detected speed is about 4 k bits per second, for three-axis output in parallel. The chip size is about 1,400 × 1,400 um², when TSMC 0.18 um 1P6 M process is employed. This 3D accelerometer can directly connect to the digital interface with three serial-port output for the information of X, Y and Z axis.