This paper studies the possibility of using axicons in Free Space Optics (FSO) systems. The behavior of the pseudo-Bessel beams generated by "logarithmic" and "linear" axicons, with or without stops, was analyzed through the Huygens-Fresnel integral of diffraction in cylindrical coordinates. We also show that GRIN (Gradient Index) axicons, when well designed, could be used in order to choose the intensity pattern along the propagation axis, which could be a new technique for the alignment equipment. © 2007 IEEE.