Study on Strengthened Two Point Calibration Algorithm

In response to the influence of calibration parameter on measurement accuracy of characteristic impedance tester, the paper comes up with a perfect calibration method of two points based on waveform average and the optimal measuring region. The method is based on calibration method of two points. First, waveform average can reduce random errors in the testing process of characteristic impedance tester. Second, automatically selection for the optimal measuring region can reach a high precision. Last, Each tube has a separate calibration parameter, increasing its consistency and Independence, which implement highly calibration for the tester. Making a integrated comparison of testing results among three algorithms, including Tektronix instrument and original method of two-point calibration, validates the accuracy of new algorithm. The method was put into the design of characteristic impedance tester using advanced measurement accuracy.