A coaxial-to-waveguide adaptor calibration method using an adjustable shorter with unspecified phases

A technique is described to remove the coaxial-to-waveguide adaptor errors when the reflection coefficient of waveguide device is measured by vector network analyzer. This technique utilizes a matched load and an adjustable shorter with several unspecified phases. And one of the shorted planes is used as reference plane. It is shown that the technique is resistant to the error of the adjustable shorter position and is easy to implement. The efficiency of this technique is verified by measurement data in X band.