| Popis: |
Preliminary experimental studies are reported of an L-band amplifier based on Hughes' plasma-assisted, slow-wave oscillator (PASOTRON) technology. The amplifier system utilizes a hollow-cathode-plasma electron-gun, and a plasma-filled slow-wave structure (SWS) to produce >= 100 microsecond(s) ec-long, 50 to 75 kV, 30 to 100-A electron beam pulses that propagate in a plasma channel without the use of any externally applied axial magnetic field. The electron-beam pulse coincides with a 100-microsecond(s) ec-long RF drive signal provided by a 2.6-kW TWT, which is coupled into the amplifier upstream of the SWS. The SWS consists of a ring-bar design which is novel to the PASOTRON family of devices and is used for its short length compared to a helix. Simulations of HP's high frequency structure simulator were used to optimize the ring-bar SWS. Preliminary data are reported showing the new L-band amplifier's gain, power, efficiency, and bandwidth. Methods of eliminating a backward wave oscillation, which was found to limit the performance of the tube, are also presented. |
