Experimental and Numerical Studies of a Magnetically Insulated Line Oscillator Working in S-Band

Summary form only given. High-power Microwave emission has been observed for the first time in S-band with our compact magnetically insulated line oscillator (MILO). The device is driven by the low impedance Marx generator GAFI 2 which was designed and built at CEA/CESTA for high-power microwave (HPM) experiments. Measurements with fast and sensitive l-dot probes, installed inside the slow wave structure (SWS), have provided the first evidence of MILO oscillation. The main frequency at 2.4 GHz is confirmed by measuring the emitted radiation, both by using an in-vacuum antenna and a horn placed in the far-field region. The frequency response of the MILO slow wave structure (SWS) is compared to a 3-D simulation 3 performed with the particle-in-cell code MAGIC. In a first configuration, we have obtained a microwave output power of 1 GW, in good agreement with the simulations. Then, we increased the pulse duration and the frequency stabilitv of emission by optimizing the cathode geometry. Finally, thanks to the fair agreement between our experimental results and the corresponding simulations, we present a design which should give a higher emitted power at 2.16 GHz.