A half gigawatt dual-moded X-band transmission and rf pulse compression system

We have produced 400 ns rf pulses of greater than 500 MW at 11.424 GHz with an rf system designed to demonstrate technology capable of powering a TeV scale electron-positron linear collider (NLC). Power is produced by four 50 MW X-band klystrons run off a common 400 kV solid-state modulator. We present the layout of our system, which includes a dual-moded transmission waveguide system and a dual-moded resonant-line (SLED-II) pulse compression system. Dual-moding of the transmission lines allows power to be directed through a pulse compression path or a bypass path; dual-moding in the pulse compressor allows the delay lines to be about half as long as they otherwise would need to be. We describe the design and performance of various components, including hybrids, directional couplers, power dividers, tapers, mode converters, and loads. These components are mostly overmoded to allow for greater power handling. We also present data on the processing and operation of this system, which is setting high-power records in pulsed rf.