Search results for "Insertion loss"

showing 10 items of 15 documents

Graphene as a tunable resistor

2014

We present the design of a graphene-based electronically tuneable microstrip attenuator operating at a frequency of 5 GHz. The use of graphene as a variable resistor is discussed and the modelling of its electromagnetic properties at microwave frequencies is fully addressed. The design of the graphene-based attenuator is described. The structure integrates a patch of graphene, whose characteristics can range from being a fairly good conductor to a highly lossy material, depending on the applied voltage. By applying the proper voltage through two high-impedance bias lines, the surface resistivity of graphene can be modified, thereby changing the insertion loss of the microstrip attenuator.

Attenuator (electronics)Settore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciMaterials sciencebusiness.industryGraphenegrapheneElectrical engineeringMicrostriplaw.inventionConductorSettore ING-IND/22 - Scienza E Tecnologia Dei MaterialilawOptoelectronicsInsertion lossResistormicrostripbusinessnanoelectronicMicrowavetuneable microwave devicesSettore CHIM/02 - Chimica FisicaVoltage2014 International Semiconductor Conference (CAS)
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Fiber-coupled dielectric-loaded plasmonic waveguides.

2010

Fiber in- and out-coupling of radiation guided by dielectric-loaded surface plasmon-polariton waveguides (DLSPPWs) is realized using intermediate tapered dielectric waveguides. The waveguide structures fabricated by large-scale UV-lithography consist of 1-microm-thick polymer ridges tapered from 10-microm-wide ridges deposited directly on a magnesium fluoride substrate to 1-microm-wide ridges placed on a 50-nm-thick and 100-microm-wide gold stripe. Using fiber-to-fiber transmission measurements at telecom wavelengths, the performance of straight and bent DLSPPWs is characterized demonstrating the overall insertion loss below 24 dB, half of which is attributed to the DLSPPW loss of propagati…

Magnesium fluorideMaterials sciencebusiness.industrySurface plasmonPhotonic integrated circuitSubstrate (electronics)DielectricSurface plasmon polaritonAtomic and Molecular Physics and Opticslaw.inventionchemistry.chemical_compoundOpticschemistrylawInsertion lossbusinessWaveguideOptics express
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Broadband tuning of a long-cavity all-fiber mode locked Thulium-doped fiber laser using an acousto-optic bandpass filter

2019

A long-cavity passively mode-locked thulium-doped all-fiber laser is reported incorporating a tapered acousto-optic tunable bandpass filter (AOTBF). The operation of the AOTBF relies on the intermodal coupling between core and cladding modes when a flexural acoustic wave propagates along an 80-microm tapered fiber. The filter works in transmission and exhibits a 3-dB bandwidth of 9.02 nm with an insertion loss of 3.4 dB. The laser supports ultrashort pulse generation at a low repetition rate of 784.93 kHz. Optical pulses with 2.43 nm of optical bandwidth and 2.1 ps pulse duration were obtained in a broad tuning range from 1824.77 to 1905.16 nm.

Materials science02 engineering and technology01 natural scienceslaw.invention010309 opticsfiber laserOpticsBand-pass filter:FÍSICA [UNESCO]lawFiber laser0103 physical sciencesInsertion lossfiber opticsthulium laserbusiness.industryBandwidth (signal processing)UNESCO::FÍSICAPulse durationmode-locked laser021001 nanoscience & nanotechnologyLaserCladding (fiber optics)Atomic and Molecular Physics and Optics0210 nano-technologybusinessUltrashort pulse
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Characterization of Different Cable Ferrite Materials to Reduce the Electromagnetic Noise in the 2–150 kHz Frequency Range

2018

The gap of standardization for conducted and field coupled electromagnetic interferences (EMI) in the 2–150 kHz frequency range can lead to Electromagnetic Compatibility (EMC) problems. This is caused by power systems such as Pulse Width Modulation (PWM) controlled rectifiers, photovoltaic inverters or charging battery units in electric vehicles. This is a very important frequency spectral due to interferences generated in a wide range of devices and, specifically, communication problems in the new technologies and devices incorporated to the traditional grid to convert it into a Smart Grid. Consequently, it is necessary to provide new solutions to attenuate this kind of interference, which…

Materials scienceAcoustics02 engineering and technology01 natural scienceslcsh:TechnologyArticlelow frequency emissionsElectric power systeminsertion lossEMI0103 physical sciencescable ferriteInsertion lossGeneral Materials Sciencelcsh:MicroscopyElectrical impedancelcsh:QC120-168.85010302 applied physicscable ferrite; electromagnetic interferences; low frequency emissions; nanocrystalline; relative permeability; insertion losselectromagnetic interferenceslcsh:QH201-278.5lcsh:TPhotovoltaic systemElectromagnetic compatibilityrelative permeability021001 nanoscience & nanotechnologylcsh:TA1-2040Ferrite (magnet)lcsh:Descriptive and experimental mechanicsnanocrystallinelcsh:Electrical engineering. Electronics. Nuclear engineering0210 nano-technologylcsh:Engineering (General). Civil engineering (General)lcsh:TK1-9971Pulse-width modulationMaterials; Volume 11; Issue 2; Pages: 174
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Characterization of Different Cable Ferrite Materials to Reduce the Electromagnetic Noise in the 2–150 kHz Frequency Range

2017

The gap of standardization for conducted and field coupled electromagnetic interferences (EMI) in the 2–150 kHz frequency range can lead to Electromagnetic Compatibility (EMC) problems. This is caused by power systems such as Pulse Width Modulation (PWM) controlled rectifiers, photovoltaic inverters or charging battery units in electric vehicles. This is a very important frequency spectral due to interferences generated in a wide range of devices and, specifically, communication problems in the new technologies and devices incorporated to the traditional grid to convert it into a Smart Grid. Consequently, it is necessary to provide new solutions to attenuate this kind of interference, which…

Materials scienceInterference (communication)EMIAcousticselectrical_electronic_engineeringElectromagnetic compatibilityFerrite (magnet)Insertion lossFilter (signal processing)Electrical impedancePulse-width modulation
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Improved All-Fiber Acousto-Optic Tunable Bandpass Filter

2017

An all-fiber acousto-optic tunable bandpass filter based on a 1.185-mm long coreless core mode blocker is reported. Experimental results demonstrate a minimal insertion loss of 1.2 dB at the optical resonant wavelength of 1527.7 nm with 3-dB optical bandwidth of 0.83 nm. The optimization of the device takes into account the attenuation of the acoustic wave and leads to an asymmetric configuration in which the coupling section is shorter than the recoupling part. Under the effect of a standing flexural wave the device can be operated as a bandpass modulator. The device exhibits a maximum modulation depth of 28%, 4 dB of insertion loss and 0.97 nm of optical bandwidth at 4.774 MHz.

Materials scienceOptical fiber02 engineering and technology01 natural scienceslaw.invention010309 opticsAmplitude modulationOpticsBand-pass filterlaw0103 physical sciencesInsertion lossOptical fibersElectrical and Electronic EngineeringModulationbusiness.industryAttenuationBandwidth (signal processing)021001 nanoscience & nanotechnologyUNESCO::FÍSICA::Óptica ::Fibras ópticasAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsWavelengthAcoustic waves:FÍSICA::Óptica ::Fibras ópticas [UNESCO]ModulationCouplings0210 nano-technologybusinessOptical attenuatorsIEEE Photonics Technology Letters
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Transmission Attenuation Power Ratio Analysis of Flexible Electromagnetic Absorber Sheets Combined with a Metal Layer.

2018

Electromagnetic noise absorber sheets have become a solution for solving complex electromagnetic interference (EMI) problems due to their high magnetic losses. This contribution is focused on characterizing a novel structure that is based on an absorber film with a metal layer attached on its top side. Two different absorber compositions were combined with Al and Cu metal layers in order to study the improvement on the performance of these structures, depending on the complex permeability, absorber film thickness, and type of metal. The transmission attenuation power ratio of the absorber films is analyzed and compared to the performance of absorber and metal structures. The measurement pro…

Materials scienceTest fixture02 engineering and technologycomplex permeability01 natural scienceslcsh:TechnologyElectromagnetic interferenceMicrostripArticlelaw.inventioninsertion losslawTransmission line0103 physical sciences0202 electrical engineering electronic engineering information engineeringEddy currentInsertion lossGeneral Materials Sciencemicrostrip lineflexible electromagnetic absorber sheetlcsh:Microscopylcsh:QC120-168.85010302 applied physicslcsh:QH201-278.5power absorptionbusiness.industrylcsh:TAttenuation020206 networking & telecommunicationselectromagnetic interferenceMagnetic fieldlcsh:TA1-2040Optoelectronicsmagnetic materialslcsh:Descriptive and experimental mechanicslcsh:Electrical engineering. Electronics. Nuclear engineeringbusinesslcsh:Engineering (General). Civil engineering (General)lcsh:TK1-9971Materials (Basel, Switzerland)
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Low Cost Electrical Current Sensors with Extremely Wide Measurement Range

2015

A new electrical current measurement system is presented. It features the ability to dynamically and automatically change its measurement range to the sensed current amplitude without user action. It also exhibits galvanic isolation and near zero insertion loss characteristics.

Materials sciencebusiness.industrySystem of measurementElectrical engineeringCurrent transducerCurrent amplitudeSettore ING-INF/01 - ElettronicaCurrent sensorElectrical currentElectricity meterRange (statistics)Power meterInsertion lossCurrent sensorbusinessGalvanic isolation
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Modulation of coaxial modal interferometers based on long period gratings in double cladding fibers

2009

This paper reports on the dynamic modulation of coaxial interferometers based on two cascaded long period gratings written in double cladding fibers. The interferometer is modulated by a piezoelectric ceramic which stretches one the gratings at tens of kHz, the output light is intensity modulated with an efficiency of 97 %. The device operates at 1530nm, has more than 50nm bandwidth, insertion loss of 0.4 dB and a temperature drift of 0.11 nm/ degrees C.

Materials sciencebusiness.industryÒpticaCladding (fiber optics)Atomic and Molecular Physics and OpticsInterferometryLight intensityOpticsWavelength-division multiplexingAstronomical interferometerOptoelectronicsInsertion lossCoaxialbusinessRefractive index
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Novel GaN Based Solid State Power Amplifiers, Results, Advances and Comparison with Vacuum Tubes Based Microwave Power Modules

2018

Power amplifiers based on vacuum tubes or solid state are key items in a number of systems. Solid state technology is growing up for some applications and it may be complementary to the vacuum technology. This paperwork presents SSPA operational principles and performance. The GaN technology available in the market, the technology roadmap, a comparison with the vacuum tubes are introduced

Microwave Power modulesMaterials scienceComputingMilieux_THECOMPUTINGPROFESSIONAmplifierVacuum tubeGallium nitrideSettore ING-INF/01 - ElettronicaEngineering physicsGeneralLiterature_MISCELLANEOUSlaw.inventionPower (physics)chemistry.chemical_compoundElectricity generationchemistrylawInsertion lossPower Amplifier: Solid state circuitTechnology roadmapRadio frequencyMicrowave TubeComputingMethodologies_COMPUTERGRAPHICS2018 IEEE 4th International Forum on Research and Technology for Society and Industry (RTSI)
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