Loss Calculations for Rectangular Coupled Bars (Correspondence)

By using slope information obtained from Getsinger´s or Gupta´s charts, it is possible to calculate incidental loss in TEM coupled-line sections using the equation for α_cc given in this correspondence. This value of loss factor can then be used to calculate incidental loss in components that include coupled-line sections for which Z₀² = Z_0eZ_0o, such as 90° backward-wave couplers and microwave C sections. An example calculation is given for a single-section 90° coupler.