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Showing 1 to 16 of 16 for “"Mode Converter"”.
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Gyrotron mode converter mirror shaping based on phase retrieval from intensity measurements
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.
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Experimental study of a high efficiency gyrotron oscillator
… low ohmic loss cavity, a four-mirror internal mode converter and a single-stage depressed collector. The low ohmic loss TE22,6 cavity, designated "V-2005", was designed using the code MAGY to have a Q factor of 830, which would be suitable for CW operation in an industrial gyrotron. The cavity …
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A Two-mode Buck Converter toward High Efficiency for the Entire Load Range for Low Power Applications
… is essential to increase the efficiency of power converters, especially at light load. This thesis research investigated a power converter to supply power for the microprocessor of a smart camera. The input voltage of the converter is 5 V, and the output voltage is 1.2 V with the load ranging from …
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Development of an online broadband impedance spectroscopy extraction system of PV modules through switch-mode converters
… technique implemented through a DC-DC switch-mode converter, has been shown to provide fast and reliable impedance information that can be utilized to diagnose the condition of batteries and fuel cells in real-time. However, the implementation of this technique in a PV system presents …
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Experimental study of a high efficiency step-tunable MW gyrotron oscillator
… a new set of components, including a cavity, mode converter, and output window were designed for operation at both frequencies. The cavity was designed using the code MAGY and the Q factors of 830 for the TE22,6,1mode at 110 GHz and 1060 for the TE24,7,1 mode at 124.5 GHz would be suitable for …
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Mode Matching sensing in Frequency Dependent Squeezing Source for Advanced Virgo plus
… the squeezed vacuum beam and the resonance mode of the cavities. The mismatch can be modelled as a simple optical loss in the first approximation. If the beam shape of squeezed vacuum does not match the resonance mode, part of its amplitude is lost and replaced with the incoherent vacuum. …
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An exploratory design of a 65 nm CMOS buck converter for maximum efficiency
… important. These small devices contain power converters that produce lower supply voltages from the fixed battery voltage source. For long battery life, it is necessary to maximize the efficiency of the power converter. A design is proposed for the topology and control of a 65 nm CMOS DC/DC …
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Design of a wideband, 100 W, 140 GHz gyroklystron amplifier
… has five cavities and operates in the TE(0,2) mode with a low power electron beam. The design was performed using MAGY, a nonlinear code for modelling gyrotron devices. The design process of the gyroklystron starting from the linear theory to the optimization of the final design in MAGY has …
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A novel wideband 140 GHz gyrotron amplifier
… presented. The gyro- TWA operates in the HE(0,6) mode of a novel cylindrical confocal waveguide using a gyrating electron beam. The electromagnetic theory, interaction theory, design processes and experimental procedures have been described in detail. The experiment has produced over 820 W peak …
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All-fiber Spectral Filters based on LP01 - LP11 Mode Coupling and Applications in Wavelength Division Multiplexing and Dispersion Compensation
… networks. Spectral filters made of single-mode identical or dissimilar core parallel fibers provide 3-dB spectral widths on the order of 1 to 10 nm. A spectral filter made of single-mode and dual-mode fibers and operating based on coupling of power between LP01 and LP11 modes is proposed …
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HIGH EFFICIENCY AXIAL DIFFRACTION OUTPUT SCHEMES FOR THE A6 RELATIVISTIC MAGNETRON
… instead using axial power extraction through a mode-converting horn antenna, resulting in improved efficiency (30% improved to 70%) and greater output power handling capability (sub-gigawatt improved to multi-gigawatt) without breakdown. In addition, axial extraction results in a more compact …
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Experimental study of a 1.5-MW, 110-GHz gyrotron oscillator
… MW was axially extracted in the design (TE22,6) mode in 3 us pulses, corresponding to a microwave efficiency of 37 %. The beam alpha, the ratio of transverse to axial velocity in the electron beam, was measured with a probe. At the high efficiency operating point the beam alpha was measured as …
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A 250 GHz photonic band gap gyrotron amplifier
… PBG interaction circuit confines the TE₀₃-like mode which couples strongly to the electron beam. The PBG circuit provides stability from oscillations by supporting the propagation of TE modes in a narrow range of frequencies, allowing for the confinement of the operating TE₀₃-like mode while …
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Frequency-tunable second-harmonic submillimeter-wave gyrotron oscillators
… generated 19 W of power in a cylindrical TE4,3,q mode from a 13-kV 190-mA electron beam. The minimum start current was measured to be 21 mA, where good agreement was verified between the measured start current values and the calculation from linear theory for the first six axial modes, q = 1 …
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ADPATIVE MODE MATCHING UPGRADE FOR ADVANCED LIGO
… to optical losses generated by optical cavity mode mismatch. Optical losses due to mode mismatched Fabry-P´erot optical cavities can be reduced by the use of adaptive optics, wavefront sensors, and feedback control loops. Advanced LIGO currently uses adaptive hardware for alignment, but not for …
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Efficient and Reliable Power Conversion Techniques for Distributed Photovoltaic Applications
L'abstract è presente nell'allegato / the abstract is in the attachment