Frequency Doubling Helical-Type Gyro-TWT for Radar Applications

The helical-type gyro-TWT has demonstrated excellent high-power and broadband operation at frequencies up to the W-band, and is also a promising candidate for future applications in the sub-THz frequency range. Recently, an extension of the helical-type gyro-TWT has been proposed, the frequency-doubling gyrotron traveling wave amplifier (FD-GTWT). The FD-GTWT delivers over a broad bandwidth high power and gain while doubling the frequency of the input signal. It is therefore of particular interest for sub-THz frequencies. However, a modified version of the FD-GTWT at lower frequencies could also be of interest for radars that require high power and a broad bandwidth, such as ground based space observation radars. An FD-GTWT may be of particular interest if an existing radar has to be upgraded to higher frequencies, since the signal generation path does not need to be replaced. For such applications, we are investigating for the first time the possibility of FD-GTWTs with center frequencies around 70 GHz that could be operated with existing Ka-band signal generation hardware.