The dispersion equation for free electromagnetic waves guided by an anisotropically conducting open tape helix is derived from the exact solution of a homogenous boundary value problem for Maxwell's equations without invoking any apriori assumption about the tape-current distribution. A numerical solution of the dispersion equation for a set of typical parameter values reveals that the tape-helix dispersion curve is virtually indistinguishable from the corresponding dominant-mode sheath helix dispersion curve except within the tape-helix forbidden regions.
"Dispersion of Electromagnetic Waves Guided by an Open Tape Helix I," Progress In Electromagnetics Research B,
Vol. 16, 311-331, 2009. doi:10.2528/PIERB09052608
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