In this paper, a novel antipodal Vivaldi antenna (AVA) is presented. The radiation flares were modified by a new composite compound exponential curve. A novel director containing two hybrid elliptical metal patches was adopted to improve the radiation parameters (gain, beam tilts and cross-polarization). The measurement results show that the proposed antenna operates from 1 GHz to more than 40 GHz with peak gain >0 dBi in the range of 1~40 GHz and >12 dBi over the 15~40 GHz range. The squinted beam of E-plane is less than 3° from 3 to 40 GHz and less than 2° from 20 to 40 GHz.