Wide-band Pulsed Travelling Wave Tube Amplifier of Kilowatt Scale for Space Application

To satisfy the requirements of new generation high resolution remote sensing satellite, the output power of pulse travelling wave tube (TWT) amplifier in space should be raised from hundred watt scale to kilowatt scale, while the bandwidth should be raised from MHz to GHz. For satellite ground applications, this paper proposed a pulsed TWT amplifier for synthetic aperture radar (SAR) systems, which achieved up to 3500 W radio frequency output power and operated at 8.2 GHz to 11.8 GHz. The pulsed TWT amplifier is composed of electronic power conditioner (EPC) and travelling wave tube (TWT). And to improve power density and solve the elements overheating problem, the parallel interleaved power converter topology is adopted to the EPC, which uses the power from storage battery of the satellite, can realize the high voltage converter of travelling wave tube, modulate the electron beam of the travelling wave tube, amplify the wide band microwave signal and finally realize the adjustment of repetition frequency and pulse width in orbit. To achieve the long life operation and stability of the TWT amplifier, as well as the satellite, the adaptive method is adopted to modulate the voltage in the electron gun. Finally, the experimental prototype is designed to verify the performance of the proposed TWT amplifier.