A Ku-band high power backward wave oscillator
01 Sep 2016-pp 177-179
TL;DR: In this paper, the design and performance of a high power backward wave oscillator working at Ku-band frequencies is described. But the performance of the beamforming scheme is not discussed.
Abstract: The paper reports on the design and performance of a high power backward wave oscillator (BWO), working at Ku-band frequencies. The rectangular waveguide grating structure is used as its slow wave structure. The backward wave oscillator is driven by a sheet beam with cross sectional area of 30mm×1mm which is generated by a thin cathode. For a beam voltage 185kV, and beam current 3.2kA, the output power is 2.5MW at 14.3GHz.
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TL;DR: In this paper, the capabilities for vacuum electronic device (VED) sources of powerful terahertz (THz) and near-THz coherent radiation, both CW or average and pulsed, were evaluated.
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TL;DR: In this paper, a millimeter-wave sheet beam backward wave oscillator is presented for high-power high-frequency microwave radiation, where the rectangular waveguide grating structure is used as its slow wave structure.
Abstract: The sheet beam vacuum electron device is an attractive choice for generating high-power high-frequency microwave radiation. A millimeter-wave sheet beam backward wave oscillator (BWO) is presented in this paper. The rectangular waveguide grating structure is used as its slow wave structure. The BWO is driven by a sheet beam with a cross-sectional area of 30 mm × 1 mm which is generated by a thin cathode. For a beam voltage of 167 kV and a beam current of 1.4 kA, the output power is 40 MW at 36.6 GHz. The beam-wave interaction efficiency is about 17%, which is higher than that of conventional hollow beam BWO. It is clear from the results presented in this paper that the sheet beam device is promising for producing high-efficiency high-power millimeter-wave radiation.
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"A Ku-band high power backward wave ..." refers background in this paper
...A report [9] was also introduced on the design of the sheet beam high-power backward wave oscillator (BWO) at 36....
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TL;DR: In this paper, the dispersion characteristics of a rectangular waveguide grating for microwave amplifier applications are investigated. But the main advantage of the procedure employed is that it gives directly and with a few spatial harmonics the dispersive relation.
Abstract: We study the dispersion characteristics of a rectangular waveguide grating for microwave amplifier applications. The Floquet theorem and an appropriate standing waves expansion is employed to express the fields in the vacuum region and inside the grooves, respectively. The application of the boundary conditions leads to an infinite system of equations, which is solved numerically by truncation. The main advantage of the procedure employed is that it gives directly and with a few spatial harmonics the dispersion relation. Furthermore, an adequate procedure (simulation tool) has been introduced in order to distinguish the real roots from spurious solutions and it has been found to work effectively for all cases presented in this work. Numerical results are presented for both shallow and deep grooves and comparison with previously published works is made.
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"A Ku-band high power backward wave ..." refers background in this paper
...By solving the dispersion equation [10][11] of the slow wave structure, we find that the grating depth h, the period p and the number of the period n dominate the dispersion relation....
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