Exceptional points of degeneracy in traveling wave tubes

Traveling wave tube (TWT) is a powerful vacuum electronic device used to amplify radio-frequency (RF) signals with numerous applications, including radar, television and telephone satellite communications. TWT design in nutshell comprises of pencil-like electron beam (e-beam) interacting guiding it slow-wave structure (SWS). In our studies here the e-beam represented by one-dimensional flow SWS transmission line (TL). The interaction between TL modeled an analytic theory that generalizes well-known Pierce model taking into account so-called space-charge effects particularly electron-to-electron repulsion (debunching). Many important aspects TWTs have been already analyzed monograph on subject. focus degeneracies dispersion relations exceptional points degeneracy their applications. term point (EPD) refers property relevant matrix nontrivial Jordan block structure. Using special parameterization suited chosen EPD we derive exact formulas for basis eigenvectors root vector associated block. Based these develop constructive approach sensing small signals.