The pulsed mode operated TWTA is used in space-based Scatterometer Systems for Remote Sensing. This Electronic Power Conditioner (EPC) has been designed and qualified for the Ocean Vector Wind Instrument used in the NASA (JPL) Remote Sensing satellite program.
The key technology in this EPC is the reliable packaging of high voltage / high power-circuitry and transformers for the 6.5 kV supply voltages of the TWT.
DC bus (unregulated): 24 – 32 V
Cathode Voltage: 6300 V, 4 mA
Cathode Voltage Tolerance (in pulse): ±2 V
Collector Voltages (4 collectors): 3400 / 2900 / 1200 / 800 V
Collector Voltage Tolerance: ±18 … 44 V
Anode Voltage: 5200 V
Grid Voltage Steps: 79/81/83/85 V
Pulse Length: 2 ms
PRF: 100 … 200 Hz
Duty Cycle: 40 %
Peak Output Power to TWT: 236 W
DC Input Power: 120 W
Efficiency: 78 %
Scatterometer Instruments for space based Remote Sensing missions
Qualification Model delivered to NASA (JPL) in 2005 ; Flight models delivered to ISRO (Indian Space Research Organisation) for their OCEANSAT Scatterometer Program in 2006.