Uncertainty contribution of the EMI test receiver in RF disturbance measurements

Measurement instrumentation uncertainty shall be taken into account when determining compliance or noncompliance with a disturbance limit in accordance with 5^th edition of CISPR 11. The corresponding uncertainty contributions to be considered for RF disturbance measurements are described in the basic standard CISPR 16-4-2. The EMI Test Receiver is one of the major uncertainty contributors particular if the estimation is done based on CISPR 16-1-1 tolerances. Using a calibrated instrument can reduce the uncertainty contribution of the EMI Test Receiver significantly. Two methods for calculating the uncertainty contribution are presented.