Application of a Calibration Procedure for EMC Analysis with an Open Directional Coupler

Automotive tests concerning electromagnetic compatibility are usually performed as hardware tests in late development stages. Because the electromagnetic environment in vehicles becomes increasingly complex, changes in these late development stages become more time consuming and financially challenging. In this paper a general calibration method for contactless electromagnetic compatibility analysis is applied with a new type of open wave coupler for the frequency range of 300 kHz to 300 MHz. It is found that the procedure lacks accuracy in the determination of phase information. An additional calibration step is proposed in order to gain the correct phase information.