Uncertainty Analysis of Dipole Antenna Calibration Above a Ground Plane

A thorough analysis of the uncertainty for dipole antenna calibration is presented. The primary standard of the antenna factor (AF) is obtained by the three-antenna method (TAM), and an ordinary calibration service is performed using the reference-antenna method (RAM). As the AF of the standard antenna is necessary for the RAM, the uncertainty analysis of TAM with the specified antenna setting is presented first, followed by the analysis of RAM. The Guide to the Expression of Uncertainty in Measurement (GUM) shows how to analyze and express the measurement uncertainties. According to the GUM, the uncertainty analysis of the calibration procedure is formulated by expressing AF as a function of other quantities, and every source of uncertainty that affects the result of the measurement is evaluated. An example of the uncertainty budget at 400 MHz is shown, and uncertainties at 24 frequencies in the range of 30 to 1000 MHz for TAM and RAM are summarized. To validate the uncertainty analyses, the differences between the calibrated and calculated AFs are shown to be smaller than the expanded uncertainties with the coverage factor of 2(k=2)