Study on Ka-band TWT with Four Helix Channels

A novel slow wave structure (SWS) based on four compressed helix channels is proposed to achieve simultaneous multiple signals amplification. It’s driven by one electron pencil beam. These four compressed helices are evenly distributed around the electron pencil beam in the middle of travelling wave tube (TWT). The input/output ports are located at ends of each compressed helix. Thus, the proposed novel SWS has four channels which are isolated from each other. Simulated results demonstrate that the proposed structure has a good transmission at 31–36GHz. The PIC simulation results show that each helix channel can get an output power of 21W and achievable gain of 16dB, when the beam voltage and current is set to 5300V and 0.4A, respectively. The multiple-channels TWT, which combines the virtues of the solid state amplifier and vacuum electronic device, is a promising SWS for miniaturized broadband electronic countermeasures (ECM). With advantage of multiple channels power synthesis, it is also an attractive choice for many applications, such as high power phased array radar detection based on vacuum electronic devices, big data radio communication, and broad-band EMI application.