Unusual electrodynamic properties of metamaterials naturally call for investigations of their applicability as slow wave structure (SWS) elements in modern microwave vacuum electron devices [1,2]. In this work, a novel microwave oscillator based on the idea of a cylindrical metamaterial SWS (MSWS) is designed. The designed MSWS, consisting of split ring resonators (SRRs) with oppositely...
Backward Wave Oscillators (BWO’s) utilizing moderately relativistic (~500kV), high-current (~10 kA) electron beams are capable of producing hundreds of MWs of pulsed radiation in the centimeter wavelength range. Such relativistic BWOs (RBWOs) allow for relatively broadband, smooth, frequency-tuning via adjustment of the accelerating potential; making them an attractive source for use in...
This study focuses on achieving wide tunabiltiy of a compact reflex triode virtual cathode oscillator (vircator). The cathode is of a bimodal carbon fiber (CF) material paired with a pyrolytic graphite anode. These materials display ideal operating characteristics which including but not limited to, long lifetime > 10^6 shots, high operating temperatures > 1000 K, and large current densities...
The transparent cathode is a cathode in which separate longitudinal emitters are periodically placed about a fixed radius from the center [1]. Owing to the longitudinal current along each emitter there is a periodic azimuthal magnetic field in which electrons drift in an applied radial electric and longitudinal DC magnetic field. Thus, this cathode in a smooth-walled tube operates as an...
A high power inverted relativistic magnetron was designed and simulated using the massively parallel electromagnetic particle-in-cell code ICEPIC in conjunction with single particle smooth bore relativistic analysis. This Inverted Magnetron also known as the Inverted Magnetron Oscillator (IMO) has two design variations, the IMO-1 and the IMO-2. Both IMO models are designed to operate in L-band...
Under the sponsorship of the Joint Non-Lethal Weapons Directorate (JNLWD), the Directed Energy Warfare Office (DEWO) at the Naval Surface Warfare Center (NSWC) Dahlgren Division has completed refurbishment of the Orion high-power radio-frequency (HPRF) system to support RF vulnerability testing. Orion is a flexible HPM source allowing for frequency agility from 1.07 GHz up to 3.3 GHz with...
With the availability of very high power (~$10^{9}$ W) and short duration (≤$10^{-9}$ s) microwave sources it is possible to study the non-linear interaction of powerful EM waves with under dense plasmas in a regime not studied so far. In contrast to the laser-plasma wakefield experiments, this approach addresses a significantly lower power, plasma density and electric field gradient regime...
Abstract: Experimental results of an L band all cavity axial extraction relativistic magnetron (RM) working at 1.57 GHz is presented. In this 6-cavity RM configuration, the microwave from two adjacent cavities is coupled into an axially oriented coaxial sector waveguide through radial slots on the cavities. This configuration is more compact because only three sector waveguides are added...