|کد مقاله||کد نشریه||سال انتشار||مقاله انگلیسی||ترجمه فارسی||نسخه تمام متن|
|4921163||1429339||2017||5 صفحه PDF||سفارش دهید||دانلود کنید|
- Ohmic loss was calculated on the grooved mirror surface in simulated polarizers.
- Polarizers with a low ohmic loss feature were optimally designed for 28Â GHz.
- Smooth rounded-rectangular grooves were made by mechanical machining.
- The designed polarizers can realize all polarization states.
In a high-power long-pulse millimeter-wave transmission line for electron cyclotron heating and current drive (ECH/ECCD), the ohmic loss on the grooved mirror surface of polarizers is one of the important issues for reducing the transmission loss. In this paper, the ohmic loss on the mirror surface is evaluated in simulated real-scale polarizer miter bends for different groove parameters under a linearly-polarized incident wave excitation. The polarizers with low ohmic loss are optimally designed for a new 28Â GHz transmission line on the QUEST spherical tokamak. The calculated optimum ohmic loss is restricted to only less than 1.5 times as large as the theoretical loss for a copper flat mirror at room temperature. The copper rounded-rectangular grooves of the polarizers were relatively easy to make smooth in mechanical machining and the resultant surface roughness was not more than 0.15Â Î¼m, which is only 0.38 times as large as the skin depth. The combination of the designed elliptical polarizer and the polarization rotator can also realize any polarization state of the reflected wave.
Journal: Fusion Engineering and Design - Volume 114, January 2017, Pages 97-101