volume | PIER Journals

Abstract

Multipacting is electron discharge that occur in components operating in RF high-power electromagnetic fields. In this paper, we will study on a new coaxial structure with ceramic window. A similar structure is utilized in many high power devices for power transfer. Due to the multipactor effect, it will generate huge heat and cause damage to the window, ultimately affect the performance of microwave devices. In order to suppress of the surface multipactor effect and improve the transmitting power, the application of an external DC bias is analyzed and simulated. A Monte Carlo algorithm is used to track the secondary electron trajectories and study the multipactor scenario on the surface of a ceramic window in a coaxial line by using 2-D particles distribution code. Since secondary electron multiplication needs to meet specific resonance conditions, an appropriate DC bias will generate a compensating trajectory and collision, which can suppress the secondary electron avalanche. The optimal value of this external bias voltage that will avoid the multipactor phenomenon in the coaxial line will be calculated by simulation in MATLAB.

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Dr. Long Yao

Dr. Long Yao

Dr. Yong Wang

Professor Xue Zhang