BROAD-BAND CALIBRATION OF E-FIELD PROBES IN LOSSY MEDIA

A broadband calibration procedure for E-field that minimizes the overa ll uncertainties inherent in measurements in lossy dielectric liquids has been developed. The analysis of the calibration requirements shows that probes that are symmetrical with respect to their axis greatly f acilitate accurate calibration, since the calibration procedure can be divided into several discrete steps, Such a procedure is presented an d analyzed with respect to its uncertainties. Absolute calibration is performed at three frequency bands utilized in Europe for mobile commu nications (450 Mhz. 900 MHz, and 1.8 GHz) and in different tissue-simu lating liquids, The parameters obtained are verified by numerical simu lations of the probe in the surrounding media, Such simulations allow the assessment of some of the calibration parameters with sufficient a ccuracy in cases where the experimental determination would be too ted ious and time consuming.