A permanent magnetic focusing system for an S-band high power MBK

Mithilesh Kumar, Ashok Bansiwal, V Nallasamy and S K Datta
Microwave Tube Research and Development Centre, DRDO, Ministry of Defence, Bangalore-560 013, India

In this paper, design and development aspects of permanent magnetic focusing system for S-band Multi-beam Klystron (MBK) has been discussed. The proposed device is designed to operate about 78 kV accelerating voltage and a total beam current of 400 Amperes distributed equally among forty beamlets. A periodic permanent magnetic focusing system is proposed for confining all these electron beamlets. Proposed magnetic focusing system has been simulated in CST-studio and simulation results have been analysed in MATLAB. The radial component of the magnetic field is found to be less than 2% of the axial component and beam transmission more than 99% could be achieved. © Anita Publications. All rights reserved.
Doi: 10.54955/AJP.34.9-10.2025.603-612
Keywords: Magnetic Focusing System (MFS), Multi-beam Klystron (MBK), Periodic Permanent Magnet (PPM), Reversible Magnetic Focusing System (RMFS).

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Method: Single- anonymous; Screened for Plagiarism? Yes
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