Accurate Analysis Equations and Synthesis Technique for Unilateral Finlines

Accurate analysis equations and synthesis techniques are presented for unilateral finlines, valid over a wide range of structural parameters and substrate dielectic constants (1≤epsilon_r≤3.75). These expressions are usable for computing the cutoff wavelength to within +-0.6 percent, the guided wavelength to within +-2 percent, and the characteristic impedance (based on the power-voltage definition) to within +-2 percent, of the spectral-domain method, over the normalized frequency range 0.25≤b/lambda≤0.6.