Design and Experiments with High Power Microwave Sources: The Virtual Cathode Oscillator
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
High-Power Microwaves (HPM) can be used to intentionally disturb or destroy electronic equipment at a distance by inducing high voltages and currents.This thesis presents results from simulations and experiments with a narrow band HPM source, the vircator. The high voltages needed to generate HPM puts the vircator under great stress, especially the electrode materials. Several electrode materials have been tested for endurance and their influence on the characteristics of the microwave pulse. With the proper materials the shot-to-shot variations are small and the geometry can be optimized in terms of e.g. output power or frequency content. Experiments with a resonant cavity added to the vircator geometry showed that with proper tuning of the cavity, the frequency content of the microwave radiation is very narrow banded and in this case the highest fields are generated. The vircator can be built in different geometries. Four different vircator types are investigated and the coaxial vircator is found to have advantages as a high radiated power and the possibility to vary the polarization during operation.Since HPM pulses are very short and have high field strengths, special field probes are needed. An HPM pulse may shift in frequency during the pulse and therefore it is very important to be able to compensate for the frequency dependence of the entire measurement system. The development and use of a far-field measurement system is described.
Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2012. , xx, 43 p.
Trita-EE, ISSN 1653-5146 ; 2012:056
High Power Microwaves Vircator
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-104794ISBN: 978-91-7501-568-2OAI: oai:DiVA.org:kth-104794DiVA: diva2:567419
2012-12-14, F3, Lindstedtsvägen 26, KTH, Stockholm, 13:30 (English)
Silfverskiöld, Stefan, Doktor
Brenning, Nils, Professor
QC 201211222012-11-222012-11-132012-11-22Bibliographically approved
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