一种新型的在线式微波功率传感器

提出了一种基于MEMS技术的在线式微波功率传感器结构,并对该结构进行了理论分析、设计、制作和测量.该结构通过测量由MEMS膜耦合出的一小部分微波功率实现功率的测量.该结构制作工艺与GaAs MMIC工艺完全兼容.测量结果显示,在12GHz频率以内,微波功率传感器的反射系数小于-15dB,插入损耗小于2dB,在10GHz中心频率下的灵敏度为10 4μV/mW.     

一种新型的在线式微波功率传感器

提出了一种基于MEMS技术的在线式微波功率传感器结构,并对该结构进行了理论分析、设计、制作和测量.该结构通过测量由MEMS膜耦合出的一小部分微波功率实现功率的测量.该结构制作工艺与GaAs MMIC工艺完全兼容.测量结果显示,在12GHz频率以内,微波功率传感器的反射系数小于-15dB,插入损耗小于2dB,在10GHz中心频率下的灵敏度为10 4μV/mW.     

一种具有工作状态转换开关结构的微机械在线式微波功率传感器

提出了一种具有工作和不工作两种状态的8GHz-12GHz宽带在线式微波功率传感器结构,该功率传感器通过测量由MEMS膜从共面波导线耦合出的一小部分微波功率实现功率的测量。为了降低功率传感器在不工作状态的微波损耗,提出了一种能够实现两种工作状态的新型的状态转换开关结构。该结构制作工艺与GaAs MMIC工艺完全兼容。测量结果显示,在10GHz中心频率处,该结构功率传感器在不工作状态下的插入损耗为0.18dB,而在工作状态下的插入损耗为0.24dB,这意味着在不工作状态下没有微波功率被耦合出来。     

T形电极晶体管

叙述了一种制作双极型晶体管的T形电极结构自对准工艺。利用该工艺已研制成微波T形电极晶体管(TSET)。最高振荡频率为10GHz,截止频率为6GHz;在3.2GHz下,输出功率1.1W,功率增益6dB。     

一种双频微波功率合成器的设计与实现

一种新型的双频微波功率合成器，通过阶跃阻抗低通滤波器和平行耦合线带通滤波器构成的微带电路实现。该微波功率合成器实现了915MHz和2．5GHz两个非相干频率微波信号的功率合成。同时通过附加工作在915MHz和2．5GHz的20dB微带定向耦合器，就可以构建实验系统进行微波功率合成的测量。实验测量结果与数值模拟结果吻合，双频微波功率合成器和定向耦合器的性能达到了要求，可用于注入式微波器件效应的研究。     

毫米波10W空间功率合成放大器研制

提出了一种结构新颖的2×2空间功率合成结构.该结构在30~36GHz范围内,回波损耗优于10dB,插入损耗小于1dB.以此结构为基础再利用4块GaAs MMIC单片制作出了一个新型的功率合成器.该功率合成器在31~34GHz的频率范围内,在±0.64dB的增益波动下能得到大于10W的输出功率,并且在31GHz时具有最大的饱和输出功率13.8W,在带内的平均合成效率大于80%.     

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。     

非掺杂AlGaN/GaN HEMT微波功率器件

介绍了非掺杂GaN HEMT微波功率器件的结构、制造工艺和测试结果.制作了几种0.6μm栅长、100～1000μm不同栅宽的器件,对于栅宽分别为100,300和500μm的器件,典型最大跨导为190～170mS/mm;截止频率比较相近,大约为24GHz;而最高振荡频率随栅宽增加而降低,分别为56,46和40GHz.测试了8GHz频率时,不同工作条件下1000μm栅宽器件的连续波微波功率特性:Vds=17V,Id=310mA,Pin=25.19dBm时,Po=30dBm(1W),Ga=4.81dB;Vds=18V,Id=290mA,Pin=27dBm时,Po=31.35dBm(1.37W),Ga=4.35dB.     

非掺杂AlGaN/GaN HEMT微波功率器件

介绍了非掺杂GaN HEMT微波功率器件的结构、制造工艺和测试结果. 制作了几种0.6μm栅长、100～1000μm不同栅宽的器件，对于栅宽分别为100, 300和500μm的器件，典型最大跨导为190～170mS/mm；截止频率比较相近，大约为24GHz；而最高振荡频率随栅宽增加而降低，分别为56, 46和40GHz. 测试了8GHz频率时，不同工作条件下1000μm栅宽器件的连续波微波功率特性：Vds=17V, Id=310mA, Pin=25.19dBm时，Po=30dBm (1W) ,Ga=4.81dB; Vds=18V, Id=290mA, Pin=27dBm时，Po=31.35dBm (1.37W) ,Ga=4.35dB.     

非掺杂AlGaN/GaN HEMT微波功率器件

介绍了非掺杂GaN HEMT微波功率器件的结构、制造工艺和测试结果.制作了几种0.6μm栅长、100～1000μm不同栅宽的器件,对于栅宽分别为100,300和500μm的器件,典型最大跨导为190～170mS/mm;截止频率比较相近,大约为24GHz;而最高振荡频率随栅宽增加而降低,分别为56,46和40GHz.测试了8GHz频率时,不同工作条件下1000μm栅宽器件的连续波微波功率特性:Vds=17V,Id=310mA,Pin=25.19dBm时,Po=30dBm(1W),Ga=4.81dB;Vds=18V,Id=290mA,Pin=27dBm时,Po=31.35dBm(1.37W),Ga=4.35dB.     

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.     

A micromachined inline type microwave power sensor with working state transfer switches

A wideband 8-12 GHz inline type microwave power sensor,which has both working and non-working states,is presented.The power sensor measures the microwave power coupled from a CPW line by a MEMS membrane.In order to reduce microwave losses during the non-working state,a new structure of working state transfer switches is proposed to realize the two working states.The fabrication of the power sensor with two working states is compatible with the GaAs MMIC(monolithic microwave integrated circuit) process.The experimental results show that the power sensor has an insertion loss of 0.18 dB during the non-working state and 0.24 dB during the working state at a frequency of 10 GHz.This means that no microwave power has been coupled from the CPW line during the non-working state.     

一种新颖三元件补偿的微带线定向耦合器研究

提出了一种在传统的微带线定向耦合器两端和中间分别加入补偿电容(简称三元件补偿)的具有高定向性、低插入损耗、低反射损耗和较宽带宽的微带线定向耦合器结构,给出了物理模型,对该结构进行了理论分析,并设计制作和测量了该种耦合器。测量结果表明,该定向耦合器的耦合度为20dB,工作频带为2.5～3.5GHz,隔离度超过-40dB,反射损耗低于-24dB,插入损耗优于-0.25dB,性能指标明显优于传统结构的微带线定向耦合器。     

基于槽线的太赫兹同相和反相功分器设计

根据接地共面波导(GCPW)和槽线的结构特点,首先设计并仿真验证了一种由接地共面波导到槽线的功分器;然后根据槽线横截面的电场分布特性,设计了一种GCPW-槽线-GCPW结构的同相功分器和反相功分器。仿真结果表明,同相功分器在175~225 GHz范围内的插入损耗优于4 dB,回波损耗优于9.6 dB;反相功分器在185~215 GHz范围内的插入损耗优于4 dB,回波损耗优于10.5 dB,幅度不平衡度小于0.24 dB,相位不平衡度小于1.3°。相比其他太赫兹功分器,本文设计的功分器在插入损耗和回波损耗相当的情况下,具有更简单、紧凑和易于集成的结构。     

Thermoelectric power sensor for microwave applications bycommercial CMOS fabrication

This work describes an implementation of a thermoelectric microwave power sensor fabricated through commercial CMOS process with additional maskless etching. The sensor combines micromachined coplanar waveguide and contact pads, a microwave termination which dissipates heat proportionally to input microwave power, and many aluminum-polysilicon thermocouples. The device was designed and fabricated in standard CMOS technology, including the appropriate superimposed dielectric openings for post-fabrication micromachining. By removing the bulk silicon located beneath the device through micromachining, thermal and electromagnetic losses are minimized. The sensor measures signal true RMS power in the frequency range up to 20 GHz with input power in the -30 dBm to +10 dBm range. Over this 40 dB dynamic range, output voltage versus input power is linear within less than ±0.16%. Automatic network analyzer data show an acceptable input return loss of less than -30 dB over the entire frequency range     

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。     

The design of miniaturized broadband power divider utilizing GaAs-based IPD process and equivalent circuit model

The GaAs-based TF-IPD fabrication process and equivalent lumped element circuit are utilized to reduce the circuit size for double-section Wilkinson power divider. Ultimately the dimension of the proposed S-band power divider is reduced to 1.03×0.98 mm². Its measured results show an operating fractional bandwidth of 54%, and return losses and isolation of greater than 20 dB. In addition the excess insertion loss is less than 1.1 dB. Moreover the good features contain amplitude and phase equilibrium with the values of better than 0.03 dB and 1.5° separately. This miniaturized power divider could be widely used in RF/microwave circuit systems.     

Microbend sensor structure for use in distributed andquasi-distributed sensor systems based on selective launching andfiltering of the modes in graded index multimode fiber

This paper describes a novel optical fiber microbend sensor architecture which my be utilized in distributed and quasi-distributed measurement. The actual sensor element is graded index multimode fiber coupled to the measurand field through the usual microbend inducing structures. However, the feed to the sensing section is through a single-mode fiber spliced to the multimode fiber to ensure that only the lowest order spatial mode is launched. Similarly the receiver is also coupled to the sensing element through a single mode fiber. The single mode within multimode fiber propagates with minimal mode coupling with source to receiver losses of typically 0.7 dB for short sensors ranging to approximately 0.3 dB per each additional kilometer of sensing fiber. The sensitivity of this structure to microbend induced losses has been thoroughly characterized. Typically the optical power loss for a given microbend structure and force is about three to six times higher in this architecture than for conventional fully mode filled microbend sensor. The structure is also almost totally insensitive to macrobend induced losses and allows a variety of novel designs in microbend inducing structures. Additionally, spatial mode filters allow effective control over concatenation effects that are common in microbend sensors     

面向5G的MEMS跷跷板结构功率传感器

为了解决5G功率传感器灵敏度不高的问题,创新性地提出一种可面向5G应用的MEMS跷跷板结构功率传感器。S参数测试结果表明,在1 GHz-10 GHz的频段内传感器的回波损耗小于-12.5 dB,插入损耗小于1.5 dB。功率响应测试表明,内部电容的灵敏度接近69.2aF/mW@1GHz、71.5aF/mW@5GHz和66.3aF/mW@10GHz,外部电容的灵敏度约为35.2aF/mW@1GHz、33.0aF/mW@5GHz和27.6aF/mW@10GHz,表明该跷跷板结构设计提高了传感器的灵敏度。     

一种基于微带与槽线过渡结构的超宽带功分器

提出了一种基于微带与槽线过渡结构的超宽带180°型3 dB功分器,采用扇形过渡结构替代传统的圆形过渡结构,拓展了功分器的工作带宽。该功分器仿真和测试结果吻合良好,在3.1~10.6 GHz频带内实现了插入损耗小于1.5 dB,两输出口的幅度误差小于0.8 dB,相位误差小于1°,输入端口反射系数小于-12 dB。