Extended cross-ratio reflection correction at microwave frequencies using waveguide air-lines

It is shown that the extended cross-ratio method of correction of the complex reflection coefficient /spl Gamma/ is applicable not only in coaxial lines but also in waveguides at microwave frequencies when precision waveguide sections of well-defined cross dimensions are used as reference air-line impedance standards. A detailed uncertainty calculation which includes the influence of waveguide imperfections is given. Small total expanded uncertainties less than 0.002 for |/spl Gamma/|/spl les/0.25 can be achieved.