Electrical characterization of integrated passive devices using thin film technology for 3D integration

With the development of 3D integration technology, microsystems with vertical interconnects are attracting attention from researchers and industry applications. Basic elements of integrated passive devices （IPDs）, including inductors, capacitors, and resistors, could dramatically save the tbotprint of the system, optimize the form factor, and improve the performance of radio frequency （RF） systems. In this paper, IPDs using thin film built-up technology are introduced, and the design and characterization of coplanar waveguides （CPWs）, inductors, and capacitors are presented.

A Stiffness Variable Passive Compliance Device with Reconfigurable Elastic Inner Skeleton and Origami Shell

Devices with variable stiffness are drawing more and more attention with the growing interests of human-robot interaction,wearable robotics,rehabilitation robotics,etc.In this paper,the authors report on the design,analysis and experiments of a stiffness variable passive compliant device whose structure is a combination of a reconfigurable elastic inner skeleton and an origami shell.The main concept of the reconfigurable skeleton is to have two elastic trapezoid four-bar linkages arranged in orthogonal.The stiffness variation generates from the passive deflection of the elastic limbs and is realized by actively switching the arrangement of the leaf springs and the passive joints in a fast,simple and straightforward manner.The kinetostatics and the compliance of the device are analyzed based on an efficient approach to the large deflection problem of the elastic links.A prototype is fabricated to conduct experiments for the assessment of the proposed concept.The results show that the prototype possesses relatively low stiffness under the compliant status and high stiffness under the stiff status with a status switching speed around 80 ms.

Creating Distinctive Connections between Multifunctional Microwave Circuits and Mobile-Terminal Radio-Frequency Integrated Chips Using Integrated Passive Device Technology

In this review,the advanced microwave devices based on the integrated passive device(IPD)technology are expounded and discussed in detail,involving the performance breakthroughs and circuit innovations.Then,the development trend of IPD-based multifunctional microwave circuits is predicted further by analyzing the current research hot spots.This paper discusses a distinctive research area for microwave circuits and mobile-terminal radio-frequency integrated chips.

Aerodynamic optimization using passive control devices near the bogie cabin of high-speed trains

Bogies are responsible for a significant amount of aerodynamic resistance and noise,both of which negatively affect high-speed train performance and passenger comfort.In the present study,the passive control method is applied in designing the bogie cabins of a high-speed train to improve its aerodynamic characteristics.Two passive control measures are introduced,namely,adding a spoiler and creating diversion grooves near the bogie cabins.Furthermore,the aerodynamic and aeroacoustic characteristics of a high-speed train operating at 350 km/h under different control strategies are numerically investigated using the improved-delayed-detached-eddy simulation(IDDES)and the acoustic finite element method(FEM).The impacts of passive control devices on drag reduction,slipstream,and aerodynamic noise are presented and discussed.Numerical results reveal that the passive control devices have a major effect on the slipstream around the train.The amplitude of the fluctuating pressure is higher in the first half of the train than in the second half.The first bogie has the maximum amplitude of the acoustic pressure for both the train with and without passive devices.In the far field,the spoiler installation and placement of the diversion grooves in the front of the bogie cabin can significantly reduce aerodynamic drag and noise.Hence,as shown in this study,using passive control methods to improve the aerodynamic and aeroacoustic properties of high-speed trains can be a viable option.

Adaptive suppression of passive intermodulation in digital satellite transceivers

For the performance issues of satellite transceivers suffering passive intermodulation interference,a novel and effective digital suppression algorithm is presented in this paper.In contrast to analog approaches,digital passive intermodulation（PIM） suppression approaches can be easily reconfigured and therefore are highly attractive for future satellite communication systems.A simplified model of nonlinear distortion from passive microwave devices is established in consideration of the memory effect.The multiple high-order PIM products falling into the receiving band can be described as a bilinear predictor function.A suppression algorithm based on a bilinear polynomial decorrelated adaptive filter is proposed for baseband digital signal processing.In consideration of the time-varying characteristics of passive intermodulation,this algorithm can achieve the rapidness of online interference estimation and low complexity with less consumption of resources.Numerical simulation results show that the algorithm can effectively compensate the passive intermodulation interference,and achieve a high signal-to-interference ratio gain.

A linear 180 nm SOI CMOS antenna switch module using integrated passive device filters for cellular applications

A broadband monolithic linear single pole, eight throw （SP8T） switch has been fabricated in 180 nm thin film silicon-on-insulator （SOI） CMOS technology with a quad-band GSM harmonic filter in integrated passive devices （IPD） technology, which is developed for cellular applications. The antenna switch module （ASM） features 1.2 dB insertion loss with filter on 2G bands and 0.4 dB insertion loss in 3G bands, less than -45 dB isolation and maximum -103 dB intermodulation distortion for mobile front ends by applying distributed architecture and adaptive supply voltage generator.

Vibration suppression of composite panel with variable angle tow design and inerter-based nonlinear energy sink

This study investigates the vibration transmission and suppression of a laminated composite panel with variable angle tow(VAT)designs and an attached inerter-based passive nonlinear energy sink.Based on analytical and numerical methodologies,the substructure technique is used to obtain a steady-state dynamic response and the results are verified by experimental and analytical methods.It is demonstrated that fiber orientation has a significant impact on the natural frequencies.The dynamic responses and energy transmission path characteristics are determined and evaluated by forced vibration analysis.The main vibration transmission paths inside the structure are displayed using power flow density vectors.It is demonstrated that the dynamic responses of the plate can be changed considerably by using various fiber placement schemes and passive suppression devices.In addition,it is indicated that the vibration transmission paths are significantly influenced by the tailored fiber angles for improved dynamic performance.Our investigation enhances the understanding of enhanced vibration suppression designs of variable-stiffness composite plates with attached passive devices.

Investigation progress on key photonic integration for application in optical communication network

Proceeding from the consideration of the demands from the functional architecture of high speed, high capacity optical communication network, this paper points out that photonic integrated devices, including high speed response laser source, narrow band response photodetector high speed wavelength converter, dense wavelength multi/demultiplexer, low loss high speed response photo-switch and multi-beam coupler are the key components in the system. The investigation progress in the laboratory will be introduced.

Characterization of on-chip balun with patterned floating shield in 65 nm CMOS

A simple method of balun synthesis is proposed to estimate the balun structure in the operating frequency band.Then,a careful optimization is implemented to evaluate the estimated structure by a series of EM simulations. In order to investigate the impact of the patterned floating shield（PFS）,the optimized baluns with and without PFS are fabricated in a 65 nm 1P6M CMOS process.The measurement results demonstrate that the PFS obviously improves the insertion loss（IL） in the frequency range and a linear improving trend appears smoothly.It is also found that the PFS gradually improves the phase balance as the frequency increases,while it has a very slight influence on the magnitude balance.To characterize the device＇s intrinsic power transfer ability,we propose a method to obtain the baluns＇ maximum available gain directly from the measured 3-port S-parameters and find that IL-comparison may not be very objective when evaluating the shielding effect.We also use the resistive coupling efficiency to characterize the shielding effect,and an imbalanced shielding efficiency is found though the PFS is perfectly symmetric in the measurement.It can be demonstrated that this phenomenon comes from the intrinsic imbalance of our balun layout.

A 500-600 MHz GaN power amplifier with RC-LC stability network

The GaAs-based TF-IPD fabrication process and equivalent lumped element circuit are utilized to re- duce 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. More- over 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.