Design of a multi-beam optical antenna using a conical laser array and an H-H lens array and analysis of coupling efficiency.

An optical antenna structure consisting of a conical laser array and a hyperboloid-hyperboloid (H-H) lens array is proposed to circumvent the central obscuration problem in Cassegrain antennas and to enable the simultaneous transmission and optical fiber coupling of multi-wavelength beams through a common antenna primary mirror. The design process of the conical laser array and H-H lens array combination, as well as the effects of various parameters on crosstalk between beams, is systematically analyzed, and ray-tracing simulations of beam propagation through the H-H lens array, the Cassegrain antenna, and the coupling lens array are carried out based on the vector laws of refraction and reflection. The simulation results based on mode-overlap theory indicate that, after accounting for lens reflection and absorption losses, the average coupling efficiency of the optical system reaches 73.98%. Additionally, the system coupling efficiency curves under three types of fiber misalignment are numerically obtained, and the corresponding coupling tolerances are determined.