200 MW S-band Dielectric Cherenkov Maser oscillator

General Dynamics is investigating the Dielectric Cherenkov Maser as a rugged, compact, and tunable high-power microwave source. This letter reports the test results of an S-band device operating at 3.8 GHz. The device consisted of a dielectric (ε=10) lined cylindrical waveguide with waveguide radius 3.63 cm, and liner thickness 0.60 cm; and an annular electron beam with radius 2.54 cm. The beam parameters were 700 keV, 12 kA, 100 ns and yielded an rf pulse of 200 MW for 20 ns. A 15 kG axial guide field was used. The measured results agree with the numerical solution of the dispersion relation which includes the effect of the beam and liner.