Frequency and power response of high-power plasma-filled backward-wave oscillators

This is the authors' abstract. We don't add key points for this paper.

Backward-wave oscillators (BWO) have long been used as voltage-tunable signal sources, and more recently as high-power microwave (HPM) sources. The frequency at which a BWO oscillates is commonly viewed as being determined by the circuit geometry and the electron beam parameters. However, several techniques used to improve the efficiency and reduce the size of HPM BWOs, such as the Pasotron, cause the frequency to vary in discrete steps with changes in the beam parameters, and a plasma in these device can cause the frequency to chirp (increase significantly) during the pulse. End reflections in low-loss circuit designs and excessive plasma generation in these new source geometries produce nonclassical frequency and power behavior.