A figure of merit for electromagnetic compatibility (EMC) testing antennas is first introduced and some design considerations are presented. A compact dipole antenna with curved reflector is proposed for 1.0-4.2 GHz EMC measurement. Structure of the curved reflector, defined by a power function, is studied by full-wave simulations and verified by experiments. A comparison between the curved reflector, corner reflector, and pyramidal reflector is presented and discussed. The presented antenna has nearly constant radiation patterns and realized gain. The minimum measurement distance is only 1.0 m for the proposed antenna, which reaches the lower limit recommended by CISPR. For small equipments under test, the measurement distance can be alternated and higher field strength can be provided by the proposed antenna without increasing the input power. In contrast, double-rigided horn antennas do not have the flexibility as they have much larger dimensions.