The paper describes an experimental study of a fractal miniature antenna radiator, which operates in ultra wideband band 3,13…15 GHz. The antenna is constructed using Rogers RO4350B material, which is a thermosetting polymer with the addition of ceramics. It was assembled on the basis of the printed circuit boards technology and complies to the 5th class of accuracy. The total antenna size including the connector equals to 19×39 mm2, its radiating part is simple and consists of two modified circles. The antenna was measured in anechoic chamber, which has proven its characteristics, including the acceptable matching in the mentioned band. Since it provides simplicity and cost reduction in case of mass production, it can be used in many other areas, such as 3G-5G and Radio-over-Fiber networks.