Experimental results from a coaxial vircator
- Texas Tech Univ., Lubbock, TX (United States). Pulsed Power Lab.
A coaxial vircator system has been developed at the High-Power Microwave Facility at Texas Tech University and the initial testing is complete. This paper details the experimental results for several different configurations of the coaxial vircator. Extensive use of particle-in-cell simulations were employed to develop an experimental prototype, which was tested in eight different configurations. Most of the design for the coaxial vircator was done with the aid of the 2.5 dimensional, particle-in-cell code, MAGIC. Simulation geometries matching the experimental system as closely as possible were developed to allow for comparison to experimental results. However, direct comparisons are not accurate because of azimuthal variations in the electron beam and microwave radiation which turned up in the experimental system. Microwaves were produced for most of the tested geometries and when peak microwave powers are divided by peak electron beam powers, efficiencies of around 1% were calculated for the best case. However, the diode is not impedance matched to the pulsed power driver and reflections cause a second, much lower voltage pulse to be applied to the diode. During this second pulse, the microwave power is at nearly the same level as during the primary pulse. Efficiency calculations during this second pulse are on the order of 10--20%. Based on this result, it may be possible to develop a source which generates long-pulse, high efficiency microwaves based on the coaxial vircator geometry.
- OSTI ID:
- 170194
- Report Number(s):
- CONF-950612--; ISBN 0-7803-2669-5
- Country of Publication:
- United States
- Language:
- English
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