Experiments and Simulations on a Prototype Recirculating Planar Magnetron

The Multi-Frequency Recirculating Planar Magnetron (MFRPM) is a type of Recirculating Planar Magnetron, a crossed-field, high power microwave source, with the added benefit of simultaneous oscillation at more than one primary frequency.\footnote{R.M. Gilgenbach et al., ``Crossed Field Device'', U.S. 2011/0204785 A1, Aug. 25, 2011, Patent Pending.} Prior research focused on the design of a dual L/S-band MFRPM prototype to demonstrate simultaneous operation at 1~GHz and 2~GHz. Dual frequency microwave emission on this prototype was recently demonstrated on the Michigan Electron Long Beam Accelerator with a ceramic insulator (MELBA-C), which drives the MFRPM by applying a -300~kV, 0.3--1.0~$\mu$s pulse to the cathode. Experiments are underway to characterize operation of the MFRPM prototype. Microwave power extraction and different cathode designs are also being explored to improve operation.\footnote{M. Franzi et al., Phys. Plasmas 20, 033108 (2013).} Results are compared to simulations of the experimental setup using the MAGIC particle-in-cell and HFSS finite-element codes.