An Optimization study on cavity magnetron

Kayan, Merve
We studied structure of cavity magnetrons and physics behind it deeply in this thesis. The main purpose of this study is to observe parameters which affect generated power of magnetron negatively or positively. Basically, they are crossedfield devices and electrons generate RF power with the help of both electric and magnetic field. We analyzed the physics of electron motion in magnetron and came up with a power equation. Then, we studied a cylindrical hole-slot-type magnetron with specific sizes and plotted curves to visualise which parameters have an effect on power and how. It was determined as a result of analyzes that applied voltage between the anode and cathode parts, resonator number, cathode radius and angular resonant frequency are directly proportional with generated power. Contrary to this, increase in gap factor and loaded quality factor decreases the generated power. After all, for used magnetron and value range of parameters that we used, the working values which give the maximum power generation are 0.5 for gap factor, 5 for the loaded quality factor and 2.2 cm for cathode radius. Moreover, much more number of resonator and higher angular resonant frequency provide much more power generation.


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Citation Formats
M. Kayan, “An Optimization study on cavity magnetron,” M.S. - Master of Science, Middle East Technical University, 2018.