Residual errors determination for vector network analyzer at a low resolution in the time domain

A method is introduced for determination of a vector network analyzer´s calibration residual errors for measurement of the reflection coefficient. The method utilizes unscented Kalman filtering and spline interpolation time domain techniques. All three residual errors are calculated by processing the measured reflection coefficient of a single verification device, such as an air line terminated with a short or open network. The proposed method shows particular advantages when the use of a long verification line is impractical (e.g. at the wafer-level), or for measurements at low frequency ranges or similar cases when the resolution of conventional time domain methods is low. Experimental studies were conducted for two frequency ranges and in coaxial and on-wafer measurement environment. The proposed algorithm is a good candidate for a wide range of practical applications especially for measurement uncertainty estimation of cost-effective vector network analyzers.