Materials Measurement Phil Bartley Shelley Begley

GRL Cal – How it worksGRL Cal Error Model (forward only)2-port Cal Terms1MUTS212-port Cal TermsTtDMsGRL ErrorAdapterS11S22GRL ErrorAdapterMlTrS12•Coax or Waveguide 2-port Cal corrects errors from end of cable back into theinstrument.•Errors from Antennas and Fixture can be thought of as being lumped into a GRL erroradapter.•The GRL error adapter is quantified by measurements of reflect and line standards.•The original 2-port Cal is modified to correct for the error adapter.Gated Reflect Line CalibrationHere is how it works. The GRL technique requires that a calibration beperformed at the ends of the cables that connect to the antennas. TheGRL technique modifies this calibration such that the reference plane istransformed from the end of the cables to the surface of the metal plateused for calibration. When the calibration is complete the empty fixturemeasures as a slice of air the thickness of the metal plate. Before themodification the fixture can be thought of as two error adapters betweenthe end of the cables and the space that the metal plate occupies.65