Title :
A 3-D U-Shaped Meander-Line Slow-Wave Structure for Traveling-Wave-Tube Applications
Author :
Ciersiang Chua ; Aditya, Shivam
Author_Institution :
Sch. of Electr. & Electron. Eng., Nanyang Technol. Univ., Singapore, Singapore
Abstract :
A novel 3-D U-shaped meander-line (ML) slow-wave structure (SWS) is proposed for traveling-wave-tube applications. This 3-D structure has the potential to have a better performance than the corresponding 2-D ML SWSs proposed in the literature. Simulation results at S-band obtained using CST Microwave Studio are presented to compare the phase velocity, interaction impedance, and circuit attenuation of the proposed structure with those of a recently reported symmetric double V-shaped microstrip ML SWS, showing advantages with respect to circuit attenuation, bandwidth, and feed design. Particle-in-cell simulations are also carried out for the proposed structure for a cylindrical electron beam using CST Particle Studio. The saturated gain and electronic efficiency of the 3-D U-shaped ML SWS is significantly higher than that of the symmetric double V-shaped ML SWS. The proposed structure has been designed and fabricated with a microstrip-line feed at S-band. The measured return loss, phase velocity, and circuit attenuation match well with the simulation results. By using microfabrication techniques, the proposed SWS has the potential to operate at millimeter-wave and higher frequencies.
Keywords :
electronic engineering computing; microfabrication; microstrip lines; slow wave structures; travelling wave amplifiers; 2D ML SWS; 3D U-shaped ML SWS; 3D U-shaped meander line slow wave structure; CST Microwave Studio; CST Particle Studio; S-band; TWT amplifier application; circuit attenuation; cylindrical electron beam; electronic efficiency; feed design; interaction impedance; microfabrication technique; microstrip line feed; millimeter-wave frequency; particle-in-cell simulation; phase velocity; return loss; saturated gain; symmetric double V-shaped microstrip ML SWS; traveling wave tube application; Attenuation; Bandwidth; Dielectric substrates; Fabrication; Feeds; Metals; Microstrip; Meander line (ML); slow-wave structure (SWS); traveling-wave tube (TWT);
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2013.2241438