Improvement on the Accuracy of Near-Field Scanning using Tangential Electric Field Probe

This paper discussed the issues about the nearfield measurement with a differential electric (E) probe. Based on the physical understanding, a method to improve the accuracy of the measured E field is proposed by suppressing the common-mode noise and eliminating the unwanted magnetic (H) field coupling. By adding ferrites around the cables that connect to the differential E field probe, suppression of the commonmode (CM) noise in the outer shield of the probe is achieved. In addition, the probe factor for the unwanted H field coupling of the E field probe is calibrated, which can be used to eliminate the H field coupling during the E field measurement. The effectiveness of the proposed method has been demonstrated in experiments. This paper provides a practical method to obtain accurate E-field measurement with a tangential E field probe, especially in the cases where the detected signal of the unwanted coupling is comparable to the wanted coupling.