Measurement Of Electrically Small Antennas

Abstract

Measurement of electrically small antennas is a great challenge due to the influence of a test cable and surrounding environment. For the elimination of an unbalanced current on nonsymmetrical feed cable, two methods can be exploited. The first one uses a quarter wave sleeve balun placed between the test cable and antenna under test for the compensation of the unbalanced current. The second one is a two-port method which measures the input impedance with suppression of the unbalanced current. Both the methods are in this contribution studied in deep and compared on the measurement of a printed dipole antenna and printed inverted F-antenna. In addition, for the antenna efficiency measurement of those antennas, a generalized Wheeler cap method is exploited.