Prediction of cold-test and hot-test characteristics of a high efficiency linear C-band helix TWT using HFSS, CTLSS, Christine 1-D/3-D

• Published in: Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) pp. 130 - 131
• Main Authors: Begum, R., Chesnut, M., Legarra, J., Stockwell, B., Cooke, S., Chernin, D.P., Chia-Lie Chang, Antonsen, T., Levush, B.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 2004
• Subjects: Circuits; Dispersion; Drives; Electromagnetic devices; Electromagnetic modeling; Electronic mail; Frequency; Impedance; Laboratories; Power industry
• ISBN: 9780780382619; 0780382617
• DOI: 10.1109/IVELEC.2004.1316233

A C-band helix traveling-wave tube (TWT) was modeled using HFSS/CTLSS (3-D electromagnetic codes) to predict the dispersion and impedance characteristics of different sections of the device. This particular TWT consists of two RF sections separated by a sever. As can be seen the input section has distributed loss along the entire length, with a tip loss in the middle; whereas the output section has distributed loss in part of the circuit, with no loss toward the end. The input section has a uniform pitch, whereas the output section has a velocity tapering with a reduction in pitch at the end to improve efficiency. This device operates in the linear region yet producing the desired RF power.