Method and apparatus for measuring a device under test using an improved through-reflect-line measurement calibration

摘要

A method of measuring a DUT provides a vector network analyzer with at least two measurement ports and measures characteristics of thru, reflect, and line calibration standards at the measurement ports. Error coefficients are calculated as well as a shifted electrical length attributable to the measured calibration standards. S-parameters of the DUT are measured and corrected based upon the error coefficients. A reference plane is shifted for each element of the corrected S-parameter matrix to a measurement reference plane, and $\frac{{\mathrm{Gamma}}_{\mathrm{SA\_portn}}}{{\mathrm{Gamma}}_{\mathrm{LA\_portm}}}=S_{21\mathrm{\_thru}\mathrm{\_nm}}{S}_{12\mathrm{\_thru}\mathrm{\_nm}}$ wherein S_21-thru-nm is equal to S_12-thru-mn and an argument of both solutions for S_21-thru-nm is fit to a straight line, the solution having a y-intercept closest to zero being a correct solution and a resulting argument of the correct solution being the electrical delay.