Particle-in-Cell Simulations of a Multiple Beam S-Band Disk-on-Rod TWT Amplifier

A high-power, pulsed operation, multibeam, S-band, coaxial disk-on-rod traveling-wave-tube amplifier has been simulated. In this paper, the amplifier, having an 81-period slow wave structure, utilized six 20-A beams. For 800 W input signals at frequencies between 2 to 4 GHz, gain and bandwidth values of 21.6 dB at 8% bandwidth and 15 dB at 15% bandwidth were observed for the beam voltages of 100 and 120 kV, respectively.