电容式MEMS微波功率传感器过载功率的优化

提出了一种等效串联电容式MEMS微波功率传感器,在不影响传感器微波性能的前提下,实现了过载功率的提升.分别建立了传感器的力学模型和集总参数模型,对过载功率特性和微波特性进行了优化与分析.使用Ansys软件和Hfss软件对传感器相关参数进行了仿真,验证了文章所建立模型的准确性.结果表明,当MIM电容相对值β从1.25变化...     

热电式MEMS微波功率传感器的封装研究

为了研究热电式MEMS微波功率传感器封装后的性能,提出了一种COB技术的封装方案。首先,采用有限元仿真软件HFSS仿真封装前后的微波特性;然后,基于GaAs MMIC技术对热电式MEMS微波功率传感器进行制备,并对制备好的芯片进行封装。最后,对封装前后传感器的微波特性及输出特性进行测试。实验结果表明,在8～12 GHz频率范围内,封装后回波损耗小于-10.50 dB,封装前的灵敏度为0.16 mV/mW@10 GHz,封装后的灵敏度为0.18 mV/mW@10 GHz。封装后的热电式微波功率传感器输出电压与输入功率仍有良好的线性度。该项研究对热电式MEMS微波功率传感器封装的研究具有一定的参考价值和指导意义。     

MEMS微波功率传感器的悬臂梁弯曲模型研究北大核心

为了研究电容式MEMS微波功率传感器悬臂梁的非线性运动，建立了MEMS悬臂梁在空间域上的弯曲特性模型，综合考虑静电力、轴向应力以及残余应力对悬臂梁非线性运动的影响，求解得到动力学微分方程。在此基础上研究在不同杨氏模量、驱动电压和残余应力下悬臂梁的弯曲特性，解析得到对应的悬臂梁弯曲特性曲线与轴向应力曲线。使用有限元分析软件ANSYS对不同驱动电压下的悬臂梁下拉位移进行仿真，并对仿真结果与解析结果进行比较。结果表明，在驱动电压从10 V到20 V的变化过程中，仿真结果与模型解析结果具有一致的趋势，两者间的最大误差仅有8.81%。对电容式MEMS微波功率传感器的悬臂梁弯曲特性的研究具有一定的参考价值和指导意义。     

一种高灵敏度在线式MEMS微波功率传感器

为了改善在线式MEMS微波功率传感器的灵敏度特性,设计了一种新型双悬臂梁结构的MEMS微波功率传感器。该结构将测试电极和锚区设计在中心信号线的两侧。建立了双悬臂梁集总电路等效模型,研究了双悬臂梁结构的微波功率传感器的微波特性。构建了枢纽式双悬臂梁静力学模型,研究并分析了新型悬臂梁结构的过载功率与灵敏度。结果表明,相比于测试电极和锚区位于信号线同侧的传统单悬臂梁结构,新型双悬臂梁结构的灵敏度提升了6～8倍。这在一定程度上解决了电容式微波功率传感器检测灵敏度较低的问题。     

热电式MEMS微波功率传感器的优化设计

为了提高热电式微波功率传感器的传热效率,改善传感器的性能,对热电式微波功率传感器的衬底结构进行了优化设计,得到了最优的衬底结构尺寸。首先研究衬底厚度对热电式微波功率传感器的影响,然后根据得到的最优衬底厚度,研究基底膜位置及尺寸对热电式微波功率传感器性能的影响,最后对所得最优衬底结构传感器的微波特性以及电磁场分布进行研究。结果表明,当传感器衬底的结构尺寸最优时,传感器的最高温度达到352.76 K,S参数小于-20.62 dB。该结构不仅减少了热量在衬底的堆积,提高了负载电阻到热电堆的热传输效率,而且具有良好的微波特性。     

热电式MEMS微波功率传感器的热学特性研究

热电转换效率直接影响热电式MEMS微波功率传感器的性能。着重对衬底掏空结构的热电式微波功率传感器进行了研究。将热电式微波功率传感器分成三个区域,建立了傅里叶模型,研究背面刻蚀的长度与厚度对热电堆热端温度的影响,发现热电堆两端温差与背面刻蚀的长度、厚度成正比。利用有限元仿真软件ANSYS,对不同刻蚀长度、厚度的传感器进行热学仿真。结果表明,背面刻蚀尺寸越大,热电堆两端的温差越大,传感器的灵敏度得到提高。仿真结果与模型结果具有较高的一致性,验证了模型的准确性。     

对称双悬臂梁结构MEMS微波功率传感器研究

为了提升电容式MEMS微波功率传感器的测量灵敏度,本文充分利用传感器的内部空间结构,提出了一种基于对称双悬臂梁结构的电容式微波功率传感器.根据对称式双梁结构的特点,建立了对称双悬臂梁结构的枢纽式机电模型.研究和分析了对称双悬臂梁结构的测量灵敏度和过载功率.实验结果表明,在悬臂梁初始间距相同的条件下,对称双梁结构的测量灵...     

MEMS微波功率传感器的系统级建模

提出了一种基于力-电和热-电原理的MEMS微波功率传感器,并依次对基于力-电转换原理的电容式MEMS微波功率传感器和基于热-电转换原理的热电式MEMS微波功率传感器进行建模.其一是通过采用挠度方程对力-电转换原理部分的固支梁建立力-电模型;二是通过采用热传导方程对热-电转换原理部分的温度分布建立二维热-电模型.最后将微...     

耦合式MEMS微波功率传感器集总参数模型的优化

耦合式MEMS微波功率传感器的集总参数模型可用于分析并计算器件的微波特性,是设计传感器相关结构尺寸的重要参考依据。针对目前传感器日益复杂化的阻抗匹配结构,对现有的集总参数模型进行了优化,并进行了相关理论推导。实验结果表明,优化后的模型计算出的反射系数最大误差为6.0 dB,插入损耗最大误差为0.7 dB,模型准确度相较于优化前有了明显的提升。因此,优化的集总参数模型对耦合式MEMS微波功率传感器的设计与优化具有一定的应用价值与参考意义。     

GaAs MEMS微波功率传感器的设计与模拟

已有的微机械直接加热终端式微波功率传感器是基于CMOS工艺的,该结构基于GaAs MMIC工艺,它可以与GaAs如微波电路实现单片集成。它的基本工作原理是热电效应,制备中使用了GaAs体加工技术来减少热量损失,并用软件对其温度场和反射系数进行了模拟。该传感器用于X波段,它的输入功率是0到50mW,灵敏度为0.54V／W,输入端S11参数约为-15dB．     

Sensitivity of MEMS microwave power sensor with the length of thermopile based on Fourier equivalent model

A Fourier equivalent model is introduced to research the thermal transfer behavior of a terminating-type MEMS microwave power sensor.The fabrication of this MEMS microwave power sensor is compatible with the GaAs MMIC process.Based on the Fourier equivalent model,the relationship between the sensitivity of a MEMS microwave power sensor and the length of thermopile is studied in particular.The power sensor is measured with an input power from 1 to 100 mW at 10 GHz,and the measurement results show that the power sensor has good input match characteristics and high linearity.The sensitivity calculated from a Fourier equivalent model is about 0.12,0.20 and 0.29 mV/mW with the length at 40,70 and 100μm,respectively,while the sensitivity of the measurement results is about 0.10,0.22 and 0.30 mV/mW,respectively,and the differences are below 0.02 mV/mW. The sensitivity expression based on the Fourier equivalent model is verified by the measurement results.     

终端式MEMS微波功率传感器的设计与制作

A terminating type MEMS microwave power sensor based on the Seebeck effect and compatible with the GaAs MMIC process is presented. An electrothermal model is introduced to simulate the heat transfer behavior and temperature distribution. The sensor measured the microwave power from –20 to 20 dBm up to 20 GHz. The sensitivity of the sensor is 0.27 mV/mW at 20 GHz, and the input return loss is less than –26 dB over the entire experiment frequency range. In order to improve the sensitivity, four different types of coplanar waveguide （CPW） were designed and the sensitivity was significantly increased by about a factor of 2.     

Design and fabrication of a terminating type MEMS microwave power sensor

A terminating type MEMS microwave power sensor based on the Seebeck effect and compatible with the GaAs MMIC process is presented.An electrothermal model is introduced to simulate the heat transfer behavior and temperature distribution.The sensor measured the microwave power from-20 to 20 dBm up to 20 GHz.The sensitivity of the sensor is 0.27 mV/mW at 20 GHz.and the input retum loss is less than-26 dB over the entire experiment frequency range.In order to improve the sensitivity,four different types of coplanar waveguide(CPW) were designed and the sensitivity Was significantly increased by about a factor of 2.     

一种基于GaAs MMIC技术的X波段电容式膜桥MEMS微波功率传感器

This paper presents the modeling, fabrication, and measurement of a capacitive membrane MEMS microwave power sensor. The sensor measures microwave power coupled from coplanar waveguide （CPW） transmission lines by a MEMS membrane and then converts it into a DC voltage output by using thermopiles. Since the fabrication process is fully compatible with the GaAs monolithic microwave integrated circuit （MMIC） process, this sensor could be conveniently embedded into MMIC. From the measured DC voltage output and S-parameters, the average sensitivity in the X-band is 225.43μV/mW, while the reflection loss is below -14 dB. The MEMS microwave power sensor has good linearity with a voltage standing wave ration of less than 1.513 in the whole X-band. In addition, the measurements using amplitude modulation signals prove that the modulation index directly influences the output DC voltage.     

A capacitive membrane MEMS microwave power sensor in the X-band based on GaAs MMIC technology

This paper presents the modeling, fabrication, and measurement of a capacitive membrane MEMS microwave power sensor. The sensor measures microwave power coupled from coplanar waveguide (CPW) transmission lines by a MEMS membrane and then converts it into a DC voltage output by using thermopiles. Since the fabrication process is fully compatible with the GaAs monolithic microwave integrated circuit (MMIC) process, this sensor could be conveniently embedded into MMIC. From the measured DC voltage output and S-parameters, the average sensitivity in the X-band is 225.43 μV/mW, while the reflection loss is below-14 dB. The MEMS microwave power sensor has good linearity with a voltage standing wave ration of less than 1.513 in the whole X-band. In addition, the measurements using amplitude modulation signals prove that the modulation index directly influences the output DC voltage.     

一种基于MEMS技术的新型对称式微波功率传感器

A novel symmetrical microwave power sensor based on MEMS technology is presented. In this power sensor, the left section inputs the microwave power, while the fight section inputs the DC power. Because of its symmetrical structure, this power sensor provides more accurate microwave power measurement capability without mismatch uncertainty and temperature drift. The loss caused by the microwave signal is simulated in this power sensor. This power sensor is designed and fabricated using GaAs MMIC technology. And it is measured in the frequency range up to 20 GHz with an input power in the 0-80 mW range. Over the 80 mW dynamic range, the sensitivity can achieve about 0.2 mV/mW. The difference between the input power in the two sections is below 0.1% for an equal output voltage. In short, the key aspect of this power sensor is that the microwave power measurement is replaced with a DC power measurement.     

A novel symmetrical microwave power sensor based on MEMS technology

A novel symmetrical microwave power sensor based on MEMS technology is presented. In this power sensor, the left section inputs the microwave power, while the right section inputs the DC power. Because of its symmetrical structure, this power sensor provides more accurate microwave power measurement capability without mismatch uncertainty and temperature drift. The loss caused by the microwave signal is simulated in this power sensor. This power sensor is designed and fabricated using GaAs MMIC technology. And it is measured in the frequency range up to 20 GHz with an input power in the 0-80 mW range. Over the 80 mW dynamic range, the sensitivity can achieve about 0.2 mV/mW. The difference between the input power in the two sections is below 0.1% for an equal output voltage. In short, the key aspect of this power sensor is that the microwave power measurement is replaced with a DC power measurement.     

终端式MEMS微波功率传感器的热时间常数研究

A terminating type MEMS microwave power sensor based on the Seebeck effect and compatible with the GaAs MMIC process is presented.An electrothermal model is introduced to simulate the thermal time constant. An analytical result,about 160 ms,of the thermal time constant from the non-stationary Fourier heat equations for the structure of the sensor is also given.The sensor measures the microwave power jumping from 15 to 20 dBm at a constant frequency 15 GHz,and the experimental thermal time constant result is 180 ms.The frequency is also changed from 20 to 10 GHz with a constant power 20 dBm,and the result is also 180 ms.Compared with the analytical and experimental results,the model is verified.     

Thermal time constant of a terminating type MEMS microwave power sensor

A terminating type MEMS microwave power sensor based on the Seebeck effect and compatible with the GaAs MMIC process is presented. An electrothermal model is introduced to simulate the thermal time constant. An analytical result, about 160 ms, of the thermal time constant from the non-stationary Fourier heat equations for the structure of the sensor is also given. The sensor measures the microwave power jumping from 15 to 20 dBm at a constant frequency 15 GHz, and the experimental thermal time constant result is 180 ms. The frequency is also changed from 20 to 10 GHz with a constant power 20 dBm, and the result is also 180 ms. Compared with the analytical and experimental results, the model is verified.     

Application of the thermoelectric MEMS microwave power sensor in a powerradiation monitoring system

A power radiation monitoring system based on thermoelectric MEMS microwave power sensors is studied. This monitoring system consists of three modules: a data acquisition module, a data processing and display module, and a data sharing module. It can detect the power radiation in the environment and the date information can be processed and shared. The measured results show that the thermoelectric MEMS microwave power sensor and the power radiation monitoring system both have a relatively good linearity. The sensitivity of the thermoelectric MEMS microwave power sensor is about 0.101 mV/mW, and the sensitivity of the monitoring system is about 0.038 V/mW. The voltage gain of the monitoring system is about 380 times, which is relatively consistent with the theoretical value. In addition, the low-frequency and low-power module in the monitoring system is adopted in order to reduce the electromagnetic pollution and the power consumption, and this work will extend the application of the thermoelectric MEMS microwave power sensor in more areas.