Low-Voltage Travelling-Wave Tubes for Space Applications

Travelling-Wave Tubes (TWTs) amplifiers represent one of the most widespread technology for space applications, thanks to a series of important features which make them unique and essential in this field. In fact, the demanding requirements of high power, high efficiency and wide bandwidth - typical of space applications - can only be achieved by means of TWTs. On the other hand, other specifications regarding dimensions, weight and power consumption are critical for these devices, which, in some cases, need to be replaced with their solid state counter part (SSAs). For this reason, it is becoming important to design novel Slow-Wave Structures (SWSs) for TWTs able to combine their above-mentioned advantages with small size and low-operating voltage. In this paper, we show some recent results carried out by our research group and concerning different interaction structures aimed at obtaining miniaturized TWTs employing a low cathodic voltage (< 2kV).