- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 7th International Conference on Reliability, Infocom Technologies and Optimization (Trends and Future Directions) (ICRITO) - Noida, India (2018.8.29-2018.8.31)] 2018 7th International Conference on Reliability, Infocom Technologies and Optimization (Trends and Future Directions) (ICRITO) - Analyzing the Internal Parameters of Free Space Optical Communication
摘要： Free Space Optical (FSO) Communication is an efficient technology as it offers higher signal bandwidth and less power for transmission. There are some internal parameters on which the performance of the FSO communication depends such as beam divergence, wavelength. The purpose is to optimize these factors to achieve the maximum output and throughput. In this paper FSO model has been designed using PIN Photodiode and Avalanche Photodiode(APD) at receiver’s side. Using the model, Q-Factor has been estimated for different beam divergences and wavelengths at varying bit rates. The results have been compared and analyzed for the two types of photodiodes.
关键词： wavelength,FSO,Beam divergence,Avalanche Photodiode,PIN,Q-Factor
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE International Conference on Unmanned Systems (ICUS) - Beijing, China (2019.10.17-2019.10.19)] 2019 IEEE International Conference on Unmanned Systems (ICUS) - Observability Enhancement of the Target Tracking Model Based on Infrared Semi-strapdown Seeker
摘要： A large petrochemical company installed nearly 50 000 hp of electrical submersible pumps (ESPs) at an existing midwest U.S. oil ?eld. Being equipped with adjustable-speed drives (ASDs), these ESPs introduced high levels of current harmonic dis-tortion, which resulted in 14%–19% voltage harmonic distortion at the electrical utility supply. Initially, the utility noticed the low power factor (PF) and had the oil company pay for the installation of power factor correction (PFC) capacitors on their medium-voltage supply. Once installed, the utility began to have problems with these capacitors and continued to receive complaints from other customers adjacent to the oil ?eld; thus, they enforced har-monic limits, as de?ned by IEEE Std 519, at all points of common coupling. Measurements were made with a harmonic analyzer at several locations throughout the electrical system to quantify harmonics and determine the effect the ESPs were having on the utility distribution system. Computer simulations were performed to analyze different methods of harmonic mitigation. Ultimately, passive harmonic ?lters were installed on all ESPs in phases. In addition, the PFC capacitors were permanently disconnected after determining that a power system resonance condition existed. Once all phases of the project were complete, the voltage distortion level decreased to below 5%, and PF improved to near unity without the PFC capacitors. This paper will describe the effect of harmonics on the electrical distribution system caused by ASDs, practical solutions to excessive voltage harmonic distortion, reso-nance issues with PFC capacitors, and the challenges associated with different methods of harmonic mitigation.
关键词： resonance,Adjustable-speed drives (ASDs),electrical submersible pumps (ESPs),harmonic quantities,harmonics,capacitors,harmonic ?lters,harmonic mitigation,power factor correction (PFC),harmonic distortion
更新于2025-09-19 17:13:59
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[IEEE 2019 24th Microoptics Conference (MOC) - Toyama, Japan (2019.11.17-2019.11.20)] 2019 24th Microoptics Conference (MOC) - Nonreciprocity Enhancement of Graphene-on-Si Waveguide using One-Dimensional Photonic Crystal
摘要： Blind interference alignment (BIA) can greatly improve the degree of freedom with the infinite signal-to-noise ratio (SNR) assumption. Under the finite SNR condition, noise accumulation can have a significantly negative impact on SNR, inducing severe performance deterioration. In particular, in multi-cell networks, the transmitter to which a user connects can further affect its received SNR and the BIA design. To address such problem, we present a user grouping scheme for reducing noise accumulation in a single cell and analyze the impact of transmitter connections on the user grouping scheme. SNR BIA in a multi-cell network is further proposed, which jointly optimizes the transmitter connection and the user grouping scheme. Extensive simulations demonstrate that the achievable sum rate of SNR BIA is 1.36 times, 1.66 times, and 2.68 times that of data shared BIA, standard BIA, and extended BIA reported in the literature, respectively, and SNR BIA is more robust to user mobility.
关键词： SNR reduced factor,effective degree of freedom,Blind interference alignment,transmitter connection
更新于2025-09-19 17:13:59
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A Single-Stage LED Streetlight Driver with Soft-Switching and Interleaved PFC Features
摘要： This paper presents a single-stage driver with soft-switching and interleaved power-factor correction (PFC) features suitable for light-emitting diode (LED) energy-saving streetlight applications. The proposed LED streetlight driver integrates an interleaved buck-boost PFC converter with coupled inductors and a half-bridge LLC resonant converter into a single-stage power-conversion circuit with reduced voltage stress on the DC-linked capacitor and power switches, and it is suitable for operating at high utility-line voltages. Furthermore, coupled inductors in the interleaved buck-boost PFC converter are operated in discontinuous-conduction mode (DCM) for accomplishing PFC, and the half-bridge LLC resonant converter features zero-voltage switching (ZVS) to reduce switching losses of power switches, and zero-current switching (ZCS) to decrease conduction losses of power diodes. Operational modes and design considerations for the proposed LED streetlight driver are introduced. Finally, a 144 W (36V/4A)-rated LED prototype driver is successfully developed and implemented for supplying a streetlight module and operating with a utility-line input voltage of 220 V. High power factor, low output-voltage ripple factor, low output-current ripple factor, and high efficiency are achieved in the proposed LED streetlight driver.
关键词： converter,soft-switching,power-factor correction (PFC),streetlight driver,LED
更新于2025-09-19 17:13:59
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Frequency Comb Generation at 800 nm in Waveguide Array Quantum Well Diode Lasers
摘要： A capacitive-piezoelectric transducer combines capacitive and piezoelectric mechanisms to achieve a combination of electromechanical coupling and Q higher than otherwise attainable by either mechanism separately, has allowed demonstration of a 1.2-GHz contour-mode aluminum nitride (AlN) ring resonator with Q > 3000 on par with the highest measured d31-transduced AlN-only piezoelectric resonators past 1 GHz, and a 50-MHz disk array with an even higher Q > 12 000. Here, the key innovation is to separate the piezoelectric resonator from its metal electrodes by tiny gaps to eliminate metal material and metal-to-piezoelectric interface losses thought to limit thin-film piezoelectric resonator Q, while also maintaining high electric field strength to preserve a strong piezoelectric effect. While Q increases, electromechanical coupling decreases, but the k2 · Q product can still increase overall. More importantly, use of the capacitive-piezo transducer allows a designer to trade electromechanical coupling for Q, providing a very useful method to tailor Q and coupling for narrowband radio frequency (RF) channel-selecting filters for which Q trumps coupling. This capacitive-piezo transducer concept does not require dc-bias voltages and allows for much thicker electrodes that reduce series resistance without mass loading the resonant structure. The latter is especially important as resonators and their supports continue to scale toward even higher frequencies.
关键词： electromechanical coupling,oscillator,Micromechanical resonator,self-alignment,small gap,aluminum nitride,equivalent circuit,quality factor,filter
更新于2025-09-19 17:13:59
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Dark Pulses in a Long Ring Laser
摘要： A capacitive-piezoelectric transducer combines capacitive and piezoelectric mechanisms to achieve a combination of electromechanical coupling and Q higher than otherwise attainable by either mechanism separately, has allowed demonstration of a 1.2-GHz contour-mode aluminum nitride (AlN) ring resonator with Q > 3000 on par with the highest measured d31-transduced AlN-only piezoelectric resonators past 1 GHz, and a 50-MHz disk array with an even higher Q > 12 000. Here, the key innovation is to separate the piezoelectric resonator from its metal electrodes by tiny gaps to eliminate metal material and metal-to-piezoelectric interface losses thought to limit thin-film piezoelectric resonator Q, while also maintaining high electric field strength to preserve a strong piezoelectric effect. While Q increases, electromechanical coupling decreases, but the k2 · Q product can still increase overall. More importantly, use of the capacitive-piezo transducer allows a designer to trade electromechanical coupling for Q, providing a very useful method to tailor Q and coupling for narrowband radio frequency (RF) channel-selecting filters for which Q trumps coupling. This capacitive-piezo transducer concept does not require dc-bias voltages and allows for much thicker electrodes that reduce series resistance without mass loading the resonant structure. The latter is especially important as resonators and their supports continue to scale toward even higher frequencies.
关键词： electromechanical coupling,oscillator,Micromechanical resonator,self-alignment,small gap,aluminum nitride,equivalent circuit,quality factor,filter
更新于2025-09-19 17:13:59
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Electro-optically tunable racetrack dual microring resonator with a high quality factor based on a Lithium Niobate-on-insulator
摘要： We propose and analyse a novel electro-optically tunable racetrack dual microring resonator with a high Q factor based on a lithium niobate-on-insulator. Using the transfer matrix method, the field transmission and attenuation of the resonator are comparatively investigated to obtain optimised coupling parameters. The enhanced Q value at the resonant wavelength of the inner ring can reach 3.873 × 106, and the blue shift of the resonant wavelength is approximately 16 nm when the applied voltages fall in a ±150 V range resulting in an electro-optic tuning rate of 0.0526 nm/V. The designed resonator presented here exhibits high performance and may offer more potential applications for lithium niobate nanophotonic devices.
关键词： electro-optic effect,lithium niobate-on-insulator,optical microring resonator,quality factor
更新于2025-09-19 17:13:59
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Ultra high-sensitivity and tunable dual-band perfect absorber as a plasmonic sensor
摘要： In this paper, we demonstrate a dual-band tunable absorber coupled with a nanoscale metal-dielectric-metal (MDM) structure for sensing applications in the near-infrared spectral region. This structure exhibits a dipole resonance mode in absorbance and reflectance spectra which results in the enhancement of absorbance over a wide range of incident angles for TE polarization. Using a numerical and analytical study, the performance parameters of the structure including sensitivity (SS), the figure of merit (FoM) and quality factor (Q) are investigated by changing the incident polarization, geometrical parameters, filling dielectric and plasmonic metasurface material. Moreover, we study the dependence of the sensitivity as a function of plasmonic metasurface shape to demonstrate a better response compared with other methods. Results show that, in terms of the refractive index unit (RIU), an ultra-high sensitivity and tunable sensor can be designed with a maximum sensitivity of 1240.8 nm/RIU for a refractive index change of Δn = 0.0458. In the optimum design of the proposed dual-band absorber, a Q-factor and FoM equal to 123.45 and 44.5 are obtained. Furthermore, the proposed structure can be utilized for controlling the light propagation. By considering silver as a plasmonic metasurface, a slow down factor as high as 680 is obtained. Our work will be applied to future sensors capable of ultra-high sensitivity.
关键词： Absorber,Nanoscale Structure,Plasmonics Sensor,Slow down factor,Metasurface
更新于2025-09-19 17:13:59
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Investigation of electrical values of low-efficiency dye-sensitized solar cells (DSSCs)
摘要： Indium-tin-oxide (ITO)/density (d)- titanium dioxide (TiO2)/nonporous (nonp)-TiO2 is a TiO2-based bilayer photoanode. These photoanodes coated for dye-sensitized solar cells (DSSCs) were with nonp-TiO2 surface and had very thick ITO layer. DSSCs were fabricated with these photoanodes. After their current density-voltage (J-V) were analyzed, ?t was seen that they were low efficiency and the shape of their J-V curve was linear line instead of rectangle. In this study, it was examined the relationship between the dark current (IDC), the series resistance (Rs) and the shunt resistance (Rsh) were examined for evaluating the fill factor (FF) of low-efficiency DSSCs because of the photoanodes with nonp-TiO2 surfaces and very thick ITO for contact layer. It was seen in the J-V graph of DSSCs which had low FF value due to their IDC and low Rsh. The J-V graph of low-efficiency DSSCs is linear due to their low Rsh and high Rs values. Moreover, the too thick ITO layer decreases the resistance of photoanodes; however, electrons in these photoanodes can not efficiently transferred to external circuit from ITO contact layer of DSSCs.
关键词： Fill factor,Linear,Nonporous,Back electron,Low-efficiency,Dark current,Cell resistance
更新于2025-09-19 17:13:59
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Monolithic Plasmonic Waveguide Architecture for Passive and Active Optical Circuits
摘要： Guided-wave plasmonic circuits are promising platforms sensing, interconnection, and quantum applications in the subdiffraction regime. Nonetheless, the loss-confinement trade-off remains a collective bottleneck for plasmonic-enhanced optical processes. Here, we report a unique plasmonic waveguide architecture that can alleviate such trade-off and improve the efficiencies of plasmonic-based emission, light-matter-interaction, and detection simultaneously. Specifically, record experimental attributes such as normalized Purcell factor approaching 104, 10 dB amplitude modulation with <1 dB insertion loss and fJ-level switching energy, and photodetection sensitivity and internal quantum efficiency of ?54 dBm and 6.4% respectively have been realized within our amorphous-based, coupled-mode plasmonic structure. The ability to support multiple optoelectronic phenomena while providing performance gains over existing plasmonic and dielectric counterparts offers a clear path toward reconfigurable, monolithic plasmonic circuits.
关键词： plasmonics,epsilon-near-zero,field-effect modulator,Purcell factor,Schottky photodetector
更新于2025-09-19 17:13:59