Second Harmonic Reduction of Traveling Wave Tube Amplifier Using Ferrite Material

Document Type : Research Paper

Authors

1 Malek Ashtar University of Technology

2 Professor of Electrical Engineering Department, Iran University if Science and Technology, Tehran, Iran.

Abstract

Traveling Wave Tubes (TWTs) consist of different elements. The most important element of TWT is the RF circuit. RF circuits in helix TWTs need a dielectric support to hold the helix; this support also has an effect in electromagnetic properties of RF circuits. A novel dielectric support is proposed to reduce the second harmonic of helix TWTs. The dielectric support in this structure consists of two sections. The first section consists of dielectric material as used in all TWT(s) supports, and the second one is a ferrite rod replaced in a portion of dielectric support. This configuration can act as a tunable band stop filter. The center frequency of the filter can be adjusted based on the second harmonic of the input frequency to reduce the second harmonic of TWT without any loss on fundamental amplified signal.

Keywords

References

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Journal of Communication Engineering
Volume 8, Issue 1 - Serial Number 16
January 2019
Pages 116-124

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