Beam propagation analysis of a multi-laser diode FSO system through free space

Abstract

In this paper beam propagation analysis of a multi-beam multi-collimator optical communication system through free space is studied. For this purpose, the propagation properties of Gaussian multi-beams through a multi-optical path including collimators in transmitters are studied and an analytical formula for intensity distribution is derived. The effects of beam divergence and beam separation distances on the propagation properties of Gaussian multi-beams are studied in detail by calculating the beam width and power in bucket (PIB). The analyses are illustrated by numerical examples.

Vector Rayleigh Diffraction of High-Power Laser Diode Beam in Optical Communication

“…Compared with the previous models of LD beam, including Hermite-Gaussian model [23], Gaussian model [25,27,28], elliptical Gaussian model [24,29], and negative exponential Gaussian model [22,30], the novel output model E y (x 0 , y 0 ) � E 0 exp(−p|x 0 | (3/2) − qy 2 0 ) in this article is more precise for single transverse model beam. For the calculation of the vector Rayleigh diffraction integrals, we expand exp(ik|r − r 0 |) into a series by keeping the first, second, and third series expansions.…”

“…us, the vector theory for nonparaxial beams should be used to precisely describe beam fields of LDs. Several models, such as exponential Gaussian function [20][21][22], Hermite-Gaussian model [23], nonparaxial diffraction of vectorial Gaussian wave [24,25], plane waves with a small aperture [26], propagation of LD beams in the optical system [27][28][29], and polarization of LD beams [30], are used to describe the beam field of LDs. However, no theoretical model is used for all cases because of the complicated beam field of LDs.…”

Fading correlation and analytical performance evaluation of the space-diversity free-space optical communications system

“…Efficient mitigation of the resulting channel fading can be obtained via spatial diversity, which has been widely adopted for applications in radio and microwave frequency bands. This can be realized by employing multiple apertures at the receiver and/or multiple beams at the transmitter [2][3][4][5][6][7]. However, such techniques lose their efficacy under the conditions of correlated fading on the underlying sub-channels, i.e., channels between pairs of transmit-receive 2040-8978/14/035403+10$33.00 apertures [8].…”