volume | PIER Journals

Abstract

This paper presents the design and fabrication of HE₁₁ miter bend along with a TM₁₁ to HE₁₁ mode converter and corrugated up-taper, which are the integral parts of a transmission line system (TLS) that carries 200 kW microwave power at 42 GHz from Gyrotron to plasma or calorimetric dummy load. It has a hybrid (HE₁₁) mode. The HE₁₁ mode transmission loss in miter bend is derived using mode-matching techniques and gap loss theory. The gap length (L) in a waveguide of diameter (D = 2a) at a wavelength (λ) for the predicted loss (D ≥ λ) is approximately 1.7[Lλ/2a²]^3/2 dB. The HE₁₁ miter bend design incorporates a demountable cooling assembly with a flat mirror. The design and optimization of the proposed miter bend were carried out using CST-microwave studio software. Finally, HE₁₁ miter bend was fabricated along with integrated assembly. The proposed HE₁₁ miter bend with mode converter and corrugated up-taper gives the transmission efficiency of 95.64%.

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Dr. Amit Patel

Dr. Pujita Bhatt

Dr. Keyur Mahant

Dr. Alpesh D. Vala

Dr. Jitendra P. Chaudhari

Dr. Hiren Mewada

Dr. Krishnamachari Sathyanarayan