Photoconductive antennas (PCA) are becoming very popular sources for the generation of Terahertz (THz) radiation. Various studies have been reported in the literature to understand the different physics involved in the operation of PCA. However, the effect of the near fields on the radiated THz from PCA is not analyzed adequately. In this work, a theoretical calculation of the radiated near fields and their effect on the radiated fields from a large aperture PCA have been investigated. The carrier dynamics presented in this work include the effect of the near fields, interaction between electrons and holes and time-dependent development of polarization due to space charge. © 2017 IEEE.