Book contents
- Microwave and RF Vacuum Electronic Power Sources
- Reviews
- The Cambridge RF and Microwave Engineering Series
- Microwave and RF Vacuum Electronic Power Sources
- Copyright page
- Dedication
- Contents
- Preface
- Principal Roman Symbols
- Principal Greek Symbols
- Abbreviations
- 1 Overview
- 2 Waveguides
- 3 Resonators
- 4 Slow-Wave Structures
- 5 Thermionic Diodes
- 6 Triodes and Tetrodes
- 7 Linear Electron Beams
- 8 Electron Flow in Crossed Fields
- 9 Electron Guns
- 10 Electron Collectors and Cooling
- 11 Beam-Wave Interaction
- 12 Gridded Tubes
- 13 Klystrons
- 14 Travelling-Wave Tubes
- 15 Magnetrons
- 16 Crossed-Field Amplifiers
- 17 Fast-Wave Devices
- 18 Emission and Breakdown Phenomena
- 19 Magnets
- 20 System Integration
- Appendix: Mathcad Worksheets
- Index
- References
3 - Resonators
Published online by Cambridge University Press: 27 April 2018
Book contents
- Microwave and RF Vacuum Electronic Power Sources
- Reviews
- The Cambridge RF and Microwave Engineering Series
- Microwave and RF Vacuum Electronic Power Sources
- Copyright page
- Dedication
- Contents
- Preface
- Principal Roman Symbols
- Principal Greek Symbols
- Abbreviations
- 1 Overview
- 2 Waveguides
- 3 Resonators
- 4 Slow-Wave Structures
- 5 Thermionic Diodes
- 6 Triodes and Tetrodes
- 7 Linear Electron Beams
- 8 Electron Flow in Crossed Fields
- 9 Electron Guns
- 10 Electron Collectors and Cooling
- 11 Beam-Wave Interaction
- 12 Gridded Tubes
- 13 Klystrons
- 14 Travelling-Wave Tubes
- 15 Magnetrons
- 16 Crossed-Field Amplifiers
- 17 Fast-Wave Devices
- 18 Emission and Breakdown Phenomena
- 19 Magnets
- 20 System Integration
- Appendix: Mathcad Worksheets
- Index
- References
Summary
Cavity resonators form an essential part of the r.f. structure in many vacuum tubes. A resonator provides a strong r.f. electric field which can interact with a stream of electrons. The basic theory of resonators and coupled resonators is reviewed using a lumped element model and the description of a resonator in terms of its frequency, shunt impedance and R/Q is explained. The effects of external loading are considered together with the excitation of a resonator by an external source. At microwave frequencies cavity resonators are used in place of lumped-element circuits. The calculation of the properties of circular and rectangular cavities is described including the effects of surface roughness on the shunt impedance. Re-entrant cavities are important in microwave tubes because they provide a strong r.f. electric field in a short interaction gap. Their properties can be calculated approximately using an equivalent circuit and, with high precision, using the method of moments. An external transmission line can be coupled to a cavity resonator using either loop or iris coupling. The calculation of the properties of both methods of coupling, including large irises, is described. The methods of measuring the properties of cavity resonators are discussed.
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- Microwave and RF Vacuum Electronic Power Sources , pp. 93 - 133Publisher: Cambridge University PressPrint publication year: 2018
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