A 500-W coupled-cavity TWT for Ka-band communication

Worldwide demand for high-power amplifiers for digital satellite communication at Ka-band frequencies between 27 and 31 GHz is steadily increasing (2003). Communication and Power Industries (CPI) has developed a 500-W periodic permanent magnet focused coupled-cavity traveling wave tube (TWT) for conduction-cooled amplifier systems, which is being introduced into the commercial satellite communication market. The TWT is capable of greater than 500-MHz instantaneous bandwidth and is cathode voltage tunable from 28.3 to 30 GHz. The TWT may be operated saturated at the 500-W output power level or backed off from saturation in the linear mode. CPI's Satcom Division has integrated the TWT into a conduction-cooled transmitter box suitable for antenna hub-mount applications. The amplifier uses predistortion networks to provide a high degree. of linear response when operated in output power back-off mode.