PPPS 2019

COAXIAL-ALL-CAVITY-EXTRACTION ON THE HARMONIC RECIRCULATING PLANAR MAGNETRON

27 Jun 2019, 10:45

15m

Seminole A/B (Double Tree at the Entrance to Universal Orlando)

Oral 2.3 Slow-Wave Devices 2.3 Slow-Wave Devices

Speakers

Dr Brad Hoff (Air Force Research Laboratory) Christopher Swenson (University of Michigan) Drew Packard (University of Michigan)Dr Geoffrey Greening (University of Michigan)Dr Jason Hammond (Air Force Research Lab) Nick Jordan (University of Michigan)Prof. R. M. Gilgenbach (University of Michigan, Ann Arbor, MI 48109, USA) Steven Exelby (University of Michigan)Prof. Y. Y. Lau (University of Michigan, Ann Arbor, MI 48109, USA)

Description

The Multi-Frequency Recirculating Planar Magnetron (MFRPM) [1,2] is a novel high power microwave (HPM) source designed to generate two frequencies simultaneously. The MFRPM is capable of producing MW power levels near 1 GHz and 2 GHz with an L-Band Oscillator (LBO) and S-Band Oscillator (SBO), respectively. The MFRPM is the first magnetron to demonstrate harmonic frequency locking, wherein the SBO frequency locked to the second harmonic of the LBO frequency. The locking mechanism between the two oscillators is presently hypothesized to be harmonic content in the electron spokes.

The Harmonic Recirculating Planar Magnetron (HRPM) has been designed and fabricated to test this hypothesis. Like the MFRPM, the HRPM still consists of an LBO and SBO. A novel scheme known as coaxial-all-cavity-extraction (CACE) [3] has been deployed to extract power from the HRPM SBO. Simulation results will be presented in addition to early experimental data obtained by driving the HRPM with the Michigan Electron Long Beam Accelerator with Ceramic insulator stack (MELBA-C). MELBA-C generates pulses 0.3-1.0 µs in length at -300 kV, with currents in the range 1-10 kA.

1. G. B. Greening, Ph.D Dissertation, “Multi-Frequency Recirculating Planar Magnetrons,” University of Michigan, 2017.
2. Greening et al, “Harmonic Frequency Locking in the Multi-Frequency Recirculating Planar Magnetron”, IEEE T-ED, vol. 65, 2347, 2018
3. Franzi et al, “Coaxial All Cavity Extraction in the Harmonic Recirculating Planar Magnetron,” IEEE International Vacuum Electronics Conference, 2014.

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• Supported by the Office of Naval Research under grant numbers N00014-13-1-0566 and N00014-16-1-2353, DEPS Fellowship support to DP, AFRL for ICEPIC, and L-3 Technologies Electron Devices Division.