Calculation of Radiation from a Helically Cut Waveguide for a Gyrotron Mode Converter in the Quasi-Optical Approximation
نویسندگان
چکیده
A gyrotron internal mode converter consists of a launcher that radiates the waveguide mode as a nearly Gaussian beam in free space, followed by a set of mirrors to focus and direct the radiation. We present a calculation of the radiation from the launcher based on a quasi-optical approach that includes diffraction. The results are in good agreement with a calculation using a numerical code based on the electric field integral equation approach. The results should be useful for designing so-called Vlasov internal mode converters and for understanding the role of diffraction in the design of internal mode converters for gyrotrons.
منابع مشابه
High efficiency quasi-optical mode converters for overmoded gyrotrons
This thesis reports on the design and experimental verification of two novel high efficiency quasi-optical mode converters for gyrotron oscillators. Gyrotrons produce high order TEm,p modes (m, p > > 1) at high frequencies (100-300 GHz). These modes must be converted to low order linearly polarized modes for transmission in corrugated waveguides or open mirror transmission lines. Because tradit...
متن کاملPSFC / JA - 10 - 62 Calculation of a Hyperbolic Corrugated Horn Converting the TEM 00 Mode to the HE 11
Corrugated waveguide transmission lines are in use to transmit high power mm-wave radiation from gyrotrons to the plasma for electron cyclotron plasma heating in tokamaks such as ITER. The coupling efficiency of the gyrotron output radiation formed as a quasi-Gaussian beam to the waveguide mode is a critical issue. A hyperbolic corrugated horn serves as a converter of the TEM00 Gaussian mode to...
متن کاملGyrotron Internal Mode Converter Reflector Shaping from Measured Field Intensity
We present the formulation and experimental results of a new approach to designing internal mode converter reflectors for high-power gyrotrons. The method employs a numerical phase retrieval algorithm that reconstructs the field in the mode converter from intensity measurements, thus accounting for the true field structure in shaping the beam-forming reflectors. An outline for designing a four-...
متن کاملCold testing of quasi-optical mode converters using a generator for non-rotating high-order gyrotron modes.
In this paper, we test the performance of a quasi-optical, internal-gyrotron mode converter. When cold testing mode converters, a rotating higher-order mode is commonly used. However, this requires a nontrivial design and precise alignment. We thus propose a new technique for testing gyrotron mode converters by using a simple, non-rotating, higher-order mode generator. We demonstrate the feasib...
متن کاملA design of Rectangular Waveguide TM11 to TE10 Mode Converter for S-band Applications
A design of a compact, easy to fabricate and applicable structure rectangular waveguide TM11 to TE10 mode converter is presented in this paper. The design procedure of the proposed structure can be divided into two parts in sequence. The beginning one is dedicated to the transformation from TM11 to TEM mode using a central conductor, while the second part is the transformation from TEM to TE10 ...
متن کامل