Comparison between three-antenna method and equivalent capacitance substitution method for calibrating electrically short monopole antenna

In low-frequency bands, monopole antennas are generally used for measuring the electromagnetic interference (EMI) and estimating the electric field strength. The antenna factor is an important and widely studied characteristic. Thus far, there have been a number of measurement methods proposed for electrically short monopole antennas. A case in point is the equivalent capacitance substitution method, which is commonly used for monopole antenna measurements. On the other hand, we have proposed a near-field three-antenna method for electrically short monopole antennas. These two absolute measurement methods are of quite different origins. In light of this fact, a comparison is made between the two measurement methods by means of experiments and simulations, and the difference observed between the antenna factors is discussed.