58 research outputs found
Packaging of RF Mems Switching Functions on Alumina Substrate
Recently the strong demands in wireless communication requires expanding
development for the application of RF MEMS (Radio Frequency micro electro
mechanical systems) sensing devices such as micro-switches, tunable capacitors
because it offers lower power consumption, lower losses, higher linearity and
higher Q factors compared with conventional communications components. To
accelerate commercialisation of RF MEMS products, development for packaging
technologies is one of the most critical issues should be solved beforehand.Comment: Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions
RF-MEMS Switched Varactors for Medium Power Applications
In RF (Radio Frequency) domain, one of the limitations of using MEMS (Micro
Electromechanical Systems) switching devices for medium power applications is
RF power. Failure phenomena appear even for 500 mW. A design of MEMS switched
capacitors with an enhanced topology is presented in this paper to prevent it.
This kind of device and its promising performances will serve to fabricate a
MEMS based phase shifter able to work under several watts.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
Le tourisme processus d'intégration des marges, réussite et échec des politiques publiques en France
Le tourisme processus dâintĂ©gration des marges, rĂ©ussite et Ă©chec des politiques publiques en France</p
Process Developments And Applications Around The Powder In Tube Technique
The purpose of this presentation is to give an overview of techniques available to produce original optical fibers and application dedicated. Some alternative fabrication solutions to the well-know stack and draw technique will be developed, following by the interest to join the stack and draw technique to other ones like RepusilÂź Technique, Rod in Tube and finally the Powder in Tube methods, first described by the Bell Lab in the seventies and up to date since some years by several groups in the world. Realization of performing optical devices such as light sources or optical sensors can be purposed by this two last original ways
Biological Cell Discrimination Based on Their High Frequency Dielectropheretic Signatures at UHF Frequencies
2017 International Microwave Symposium paper entitled "Biological Cell Discrimination Based on Their High Frequency Dielectropheretic Signatures at UHF Frequencies". Honolulu June 4-9th 2017. Amended version: see additional notes.This version amends the wrong naming in the previous record: the conference is the IEEE IMS 2017, not 2018
Finished Genome of the Fungal Wheat Pathogen Mycosphaerella graminicola Reveals Dispensome Structure, Chromosome Plasticity, and Stealth Pathogenesis.
The plant-pathogenic fungus Mycosphaerella graminicola (asexual stage: Septoria tritici) causes septoria tritici blotch, a disease that greatly reduces the yield and quality of wheat. This disease is economically important in most wheat-growing areas worldwide and threatens global food production. Control of the disease has been hampered by a limited understanding of the genetic and biochemical bases of pathogenicity, including mechanisms of infection and of resistance in the host. Unlike most other plant pathogens, M. graminicola has a long latent period during which it evades host defenses. Although this type of stealth pathogenicity occurs commonly in Mycosphaerella and other Dothideomycetes, the largest class of plant-pathogenic fungi, its genetic basis is not known. To address this problem, the genome of M. graminicolawas sequenced completely. The finished genome contains 21 chromosomes, eight of which could be lost with no visible effect on the fungus and thus are dispensable. This eight-chromosome dispensome is dynamic in field and progeny isolates, is different from the core genome in gene and repeat content, and appears to have originated by ancient horizontal transfer from an unknown donor. Synteny plots of the M. graminicola chromosomes versus those of the only other sequenced Dothideomycete, Stagonospora nodorum, revealed conservation of gene content but not order or orientation, suggesting a high rate of intra-chromosomal rearrangement in one or both species. This observed âmesosyntenyâ is very different from synteny seen between other organisms. A surprising feature of the M. graminicolagenome compared to other sequenced plant pathogens was that it contained very few genes for enzymes that break down plant cell walls, which was more similar to endophytes than to pathogens. The stealth pathogenesis of M. graminicola probably involves degradation of proteins rather than carbohydrates to evade host defenses during the biotrophic stage of infection and may have evolved from endophytic ancestors
Distributed MEMS tunable filters
This paper focus on the design of MEMS distributed tunable millimeter wave filters. A two pole filter continuously tunable in bandwidth and in frequency with constant input/output impedance is described. The center frequency can be tuned from 37.8 GHz to 40.4 GHz and the bandwidth can be changed from 1.6 GHz to 1 GHz with constant return losses
Integrated Millimeter-Wave Silicon Micromachined Filters
This paper describes the design and the fabrication of a new type of millimeter-wave micromachined band pass filters, using silicon waveguides. The main interest of these components is their ability to be integrated along with other MMICs using flip chip bonding techniques. The micromachining fabrication technique allows to maintain very good fabrication tolerances, while the resulting filters are very compact. The design methodology is presented along with two examples of two and four pole filters at 42 GHz. applied to these filters and at last simulation results on 2 and 4 pole bandpass filters
Packaged Millimeter Wave Thermal MEMS Switches
This abstract describes MEMS thermally actuated millimeter wave switches. The switches are constructed using a stress controlled dielectric membrane, with patterned metallic contacts. The resulting switches can be operated at low voltage, without sacrificing the spring constant. The structure allows to build resistive switches up to millimeter wave. Full wave simulations were performed using FEM and MoM codes, and agree well with measurements. A wafer scale packaging technique has been developed to protect the components during the dicing stage, and for long term durability. The measured isolation are better than 35 dB between 30 and 40 GHz
- âŠ