Trademark A combination broadband antenna in which a log-periodic antenna is used for the higher part of its frequency range and a bow-tie antenna is joined to the back of the transmission line to provide a lower limit to the frequency range than with just a log-periodic of comparable size. The addition of the bow-tie element necessitates a balun behind the bow-tie in order to ensure that the structure does not become unbalanced in the lower part of its operating frequency range. The Bilog antenna is commonly used in electromagnetic compatibility testing due to its compact size and wide frequency range.