Fiber Lens Based Optical Antenna Design for OWC With Full Beam Coverage

Abstract

In infrared optical wireless communications, narrow beams require the perfect calibration of the base station (BS) and user terminal (UT), which cannot support multiple moving users. This paper proposes a fiber lens based optical antenna, which employs a fiber unit array and a transmit lens to generate multiple beams, achieving full beam coverage. Specifically, we first design a fiber lens to extend the spreading angle of the emitted lights. We employ the wave optics to analyze the characteristic of the fiber lens and use the geometric optics to design the parameters of the lens. With the fiber lens, we then design the optical antenna consisting of a hexagonal fiber unit array and a transmit lens. Each fiber unit generates a beam to a specific direction and different fiber units irradiate different directions. All the generated beams can fully cover the communication area. Thus, the BS has the potential to support multi-user communication via multiple beams. Simulation results verify the performance of the designed fiber lens and the optical antenna achieving full beam coverage.