A kind of novel tape helical slow wave structure (SWS) is supported by wedge-shaped discontinuous dielectric pillars and brazed with the helix and metal envelope through two metal connectors.The dielectric pillars exist only at the tape helix in each pitch.It has higher power capacity and broader bandwidth.The hybrid model for analyzing the tape helix is developed in this paper.In this model

by expanding the surface currents on the tape helix in a series of Chebyshev polynomials

simulating the helical radial thickness with vacuum layer

equalizing the discontinuous dielectric pillars with multiple azimuthally symmetric layers

assuming an infinite number of infinitely thin radial vanes and considering the metal connectors

the dispersion equation and interaction impedance of the novel helical SWS are obtained.In the meantime

the tape helical SWS is simulated by HFSS.The calculated results using the model presented in the paper show good agreements with HFSS simulation results.The theory presented here can provide a strong basis for designing the tape helical SWS.