Study on Impact of Different Electrode Materials on the Collector Performance in TWTs

Attaining good collector performance in terms of high collector efficiency, low backstreaming, and body interception current has been a prime motive for traveling wave tube (TWT) designers. Selection of appropriate electrode material can result in enhancement of collector performance for the same electrical design (with same electrode potentials and electrode geometry). Here, attempts have been made to quantitatively demonstrate the unexplored impact of electrode material selection on the collector performance systematically. The effect of electrode material on collector efficiency, backstreaming current, body interception current, and their fluctuations arising in a practical scenario due to the variations in input power drives and electrode potentials has been studied. This study has been extended for two different types of TWTs–one with high electronic efficiency and another with medium electronic efficiency at different operating frequencies. Five different electrode materials have been studied with precise recommendations provided for each of the two types of TWTs.