The necessity of using fiber-optic communication lines (FOCL) for testing active phased antenna arrays (APAA) in landfill conditions in a complex electromagnetic environment is substantiated. The advantages of FOCL application for working with microwave signals during testing of various antennas especially in the far zone are noted. The developed two-channel FOCL for measuring APAA parameters in the far zone is presented. The choice of the components of the optical system for transmitting microwave signals is justified. The results of the study of the characteristics of the fiber optic and directional patterns of antenna arrays are presented.