A modified microstrip meander-line slow wave structure for planar traveling wave tubes

In this paper, a modified microstrip meander-line (MML) slow wave structure (SWS) for planar traveling wave tubes (TWTs) is described with the analysis of its dispersion characteristics, interaction impedances and transmission properties. Compared with conventional MML SWS, the modified SWS has wider cold band with an increased rate of about 53.5% and larger interaction impedances (21.4% increased). What's more, the metal MML has better connection with the dielectric rod, which improves stability and reliability under thermal shock, stress impact and electron bombardment.